git.iko.soy/squeal
on 1f4db59 help sign in
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.circleci/config.yml+2−3
since splitsnapshots
unifiedsplit
@@ -2,10 +2,9 @@ version: 2
2jobs:
2jobs:
3 build:
3 build:
4 docker:
4 docker:
5− - image: haskell:8.6.5
5+ - image: haskell:8.2.2
6 - image: circleci/postgres:latest
6 - image: circleci/postgres:latest
7 environment:
7 environment:
8− POSTGRES_USER: root
9 POSTGRES_DB: exampledb
8 POSTGRES_DB: exampledb
10 steps:
9 steps:
11 - checkout
10 - checkout
@@ -14,7 +13,7 @@ jobs:
14 - dependency-cache
13 - dependency-cache
15 - run: apt-get update && apt-get install -y libpq-dev xz-utils make
14 - run: apt-get update && apt-get install -y libpq-dev xz-utils make
16 - run: stack upgrade && stack update
15 - run: stack upgrade && stack update
17− - run: stack build --fast
16+ - run: stack build
18 - run: stack test
17 - run: stack test
19 - run: stack haddock
18 - run: stack haddock
20 - save_cache:
19 - save_cache:
README.md+87−83
@@ -45,12 +45,7 @@ composable and cover a large portion of SQL.
45* connection pools
45* connection pools
46* transactions
46* transactions
47* views
47* views
48−* array, composite and enumerated types
48+* composite and enumerated types
49−* json functions and operations
50−* multischema support
51−* correlated subqueries
52−* window functions
53−* text search
54
49
55## installation
50## installation
56
51
@@ -58,16 +53,10 @@ composable and cover a large portion of SQL.
58
53
59## testing
54## testing
60
55
61−Start postgres on localhost port `5432` and create a database named `exampledb`.
56+start postgres on localhost port `5432` and create a database named `exampledb`.
62
57
63`stack test`
58`stack test`
64
59
65−## contributing
66−
67−We welcome contributors.
68−Please make pull requests on the `dev` branch instead of `master`.
69−The `Issues` page is a good place to communicate.
70−
71## usage
60## usage
72
61
73Let's see an example!
62Let's see an example!
@@ -76,17 +65,19 @@ First, we need some language extensions because Squeal uses modern GHC
76features.
65features.
77
66
78```Haskell
67```Haskell
79−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
68+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
80−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
69+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators
81```
70```
82
71
83We'll need some imports.
72We'll need some imports.
84
73
85```Haskell
74```Haskell
86−>>> import Control.Monad.IO.Class (liftIO)
75+>>> import Control.Monad (void)
76+>>> import Control.Monad.Base (liftBase)
87>>> import Data.Int (Int32)
77>>> import Data.Int (Int32)
88>>> import Data.Text (Text)
78>>> import Data.Text (Text)
89>>> import Squeal.PostgreSQL
79>>> import Squeal.PostgreSQL
80+>>> import Squeal.PostgreSQL.Render
90```
81```
91
82
92We'll use generics to easily convert between Haskell and PostgreSQL values.
83We'll use generics to easily convert between Haskell and PostgreSQL values.
@@ -101,27 +92,27 @@ we use `DataKinds` and `TypeOperators`.
101
92
102```Haskell
93```Haskell
103>>> :{
94>>> :{
104−type UsersColumns =
105− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
106− , "name" ::: 'NoDef :=> 'NotNull 'PGtext ]
107−type UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]
108−type EmailsColumns =
109− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
110− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
111− , "email" ::: 'NoDef :=> 'Null 'PGtext ]
112−type EmailsConstraints =
113− '[ "pk_emails" ::: 'PrimaryKey '["id"]
114− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"] ]
115type Schema =
95type Schema =
116− '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)
96+ '[ "users" ::: 'Table (
97+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
98+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
99+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
100+ ])
117− , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]
101+ , "emails" ::: 'Table (
118−type Schemas = Public Schema
102+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
103+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
104+ ] :=>
105+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
106+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
107+ , "email" ::: 'NoDef :=> 'Null 'PGtext
108+ ])
109+ ]
119:}
110:}
120```
111```
121
112
122Notice the use of type operators.
113Notice the use of type operators.
123
114
124−`:::` is used to pair an alias `Symbol` with a `SchemumType`,
115+`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemumType`,
125a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's `::`
116a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's `::`
126operator.
117operator.
127
118
@@ -130,7 +121,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
130yielding a `ColumnType`. It is intended to connote Haskell's `=>` operator
121yielding a `ColumnType`. It is intended to connote Haskell's `=>` operator
131
122
132Next, we'll write `Definition`s to set up and tear down the schema. In
123Next, we'll write `Definition`s to set up and tear down the schema. In
133−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
124+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
134has two type parameters, corresponding to the schema
125has two type parameters, corresponding to the schema
135before being run and the schema after. We can compose definitions using `>>>`.
126before being run and the schema after. We can compose definitions using `>>>`.
136Here and in the rest of our commands we make use of overloaded
127Here and in the rest of our commands we make use of overloaded
@@ -139,19 +130,19 @@ labels to refer to named tables and columns in our schema.
139```Haskell
130```Haskell
140>>> :{
131>>> :{
141let
132let
142− setup :: Definition (Public '[]) Schemas
133+ setup :: Definition '[] Schema
143− setup =
134+ setup =
144 createTable #users
135 createTable #users
145− ( serial `as` #id :*
136+ ( serial `As` #id :*
146− (text & notNullable) `as` #name )
137+ (text & notNullable) `As` #name :* Nil )
147− ( primaryKey #id `as` #pk_users ) >>>
138+ ( primaryKey #id `As` #pk_users :* Nil ) >>>
148 createTable #emails
139 createTable #emails
149− ( serial `as` #id :*
140+ ( serial `As` #id :*
150− (int & notNullable) `as` #user_id :*
141+ (int & notNullable) `As` #user_id :*
151− (text & nullable) `as` #email )
142+ (text & nullable) `As` #email :* Nil )
152− ( primaryKey #id `as` #pk_emails :*
143+ ( primaryKey #id `As` #pk_emails :*
153 foreignKey #user_id #users #id
144 foreignKey #user_id #users #id
154− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
145+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
155:}
146:}
156```
147```
157
148
@@ -171,7 +162,7 @@ primary and foreign keys, making them somewhat complex. Our `teardown`
171```Haskell
162```Haskell
172>>> :{
163>>> :{
173let
164let
174− teardown :: Definition Schemas (Public '[])
165+ teardown :: Definition Schema '[]
175 teardown = dropTable #emails >>> dropTable #users
166 teardown = dropTable #emails >>> dropTable #users
176:}
167:}
177
168
@@ -180,57 +171,57 @@ DROP TABLE "emails";
180DROP TABLE "users";
171DROP TABLE "users";
181```
172```
182
173
183−We'll need a Haskell type for `User`s. We give the type `SOP.Generic` and
184−`SOP.HasDatatypeInfo` instances so that we can encode and decode `User`s.
185−
186−```Haskell
187−>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
188−>>> instance SOP.Generic User
189−>>> instance SOP.HasDatatypeInfo User
190−```
191−
192−Next, we'll write `Manipulation_`s to insert `User`s into our two tables.
174+Next, we'll write `Manipulation`s to insert data into our two tables.
193−A `Manipulation_` like `insertInto`, `update` or `deleteFrom`
175+A `Manipulation` like `insertRow`, `update` or `deleteFrom`
194−has three type parameters, the schemas it refers to, input parameters
176+has three type parameters, the schema it refers to, a list of parameters
195−and an output row. When
177+it can take as input, and a list of columns it produces as output. When
196we insert into the users table, we will need a parameter for the `name`
178we insert into the users table, we will need a parameter for the `name`
197field but not for the `id` field. Since it's serial, we can use a default
179field but not for the `id` field. Since it's serial, we can use a default
198value. However, since the emails table refers to the users table, we will
180value. However, since the emails table refers to the users table, we will
199need to retrieve the user id that the insert generates and insert it into
181need to retrieve the user id that the insert generates and insert it into
200−the emails table. We can do this in a single `Manipulation_` by using a
182+the emails table. Take a careful look at the type and definition of both
201−`with` statement.
183+of our inserts.
202
184
203```Haskell
185```Haskell
204>>> :{
186>>> :{
205let
187let
206− insertUser :: Manipulation_ Schemas User ()
188+ insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]
207− insertUser = with (u `as` #u) e
189+ insertUser = insertRow #users
208− where
209− u = insertInto #users
210− (Values_ (Default `as` #id :* Set (param @1) `as` #name))
190+ (Default `As` #id :* Set (param @1) `As` #name :* Nil)
211− OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))
191+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))
212− e = insertInto_ #emails $ Select
192+:}
213− (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)
193+
214− (from (common #u))
194+>>> :{
195+let
196+ insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
197+ insertEmail = insertRow #emails
198+ ( Default `As` #id :*
199+ Set (param @1) `As` #user_id :*
200+ Set (param @2) `As` #email :* Nil )
201+ OnConflictDoNothing (Returning Nil)
215:}
202:}
216
203
217>>> printSQL insertUser
204>>> printSQL insertUser
218−WITH "u" AS (INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) RETURNING "id" AS "id", ($2 :: text) AS "email") INSERT INTO "emails" ("user_id", "email") SELECT "u"."id", "u"."email" FROM "u" AS "u"
205+INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) ON CONFLICT DO NOTHING RETURNING "id" AS "fromOnly"
206+>>> printSQL insertEmail
207+INSERT INTO "emails" ("id", "user_id", "email") VALUES (DEFAULT, ($1 :: int4), ($2 :: text)) ON CONFLICT DO NOTHING
219```
208```
220
209
221−Next we write a `Query_` to retrieve users from the database. We're not
210+Next we write a `Query` to retrieve users from the database. We're not
222interested in the ids here, just the usernames and email addresses. We
211interested in the ids here, just the usernames and email addresses. We
223−need to use an `innerJoin` to get the right result. A `Query_` is like a
212+need to use an inner join to get the right result. A `Query` is like a
224−`Manipulation_` with the same kind of type parameters.
213+`Manipulation` with the same kind of type parameters.
225
214
226```Haskell
215```Haskell
227>>> :{
216>>> :{
228let
217let
229− getUsers :: Query_ Schemas () User
218+ getUsers :: Query Schema '[]
219+ '[ "userName" ::: 'NotNull 'PGtext
220+ , "userEmail" ::: 'Null 'PGtext ]
230− getUsers = select_
221+ getUsers = select
231− (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)
222+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* Nil)
232− ( from (table (#users `as` #u)
223+ ( from (table (#users `As` #u)
233− & innerJoin (table (#emails `as` #e))
224+ & innerJoin (table (#emails `As` #e))
234 (#u ! #id .== #e ! #user_id)) )
225 (#u ! #id .== #e ! #user_id)) )
235:}
226:}
236
227
@@ -238,13 +229,25 @@ let
238SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
229SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
239```
230```
240
231
232+Now that we've defined the SQL side of things, we'll need a Haskell type
233+for users. We give the type `Generics.SOP.Generic` and
234+`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows
235+we receive when we run `getUsers`. Notice that the record fields of the
236+`User` type match the column names of `getUsers`.
237+
238+```Haskell
239+>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
240+>>> instance SOP.Generic User
241+>>> instance SOP.HasDatatypeInfo User
242+```
243+
241−Let's create some users to add to the database.
244+Let's also create some users to add to the database.
242
245
243```Haskell
246```Haskell
244>>> :{
247>>> :{
245let
248let
246 users :: [User]
249 users :: [User]
247− users =
250+ users =
248 [ User "Alice" (Just "alice@gmail.com")
251 [ User "Alice" (Just "alice@gmail.com")
249 , User "Bob" Nothing
252 , User "Bob" Nothing
250 , User "Carole" (Just "carole@hotmail.com")
253 , User "Carole" (Just "carole@hotmail.com")
@@ -263,18 +266,19 @@ transformer and when the schema doesn't change we can use `Monad` and
263```Haskell
266```Haskell
264>>> :{
267>>> :{
265let
268let
266− session :: PQ Schemas Schemas IO ()
269+ session :: PQ Schema Schema IO ()
267 session = do
270 session = do
268− _ <- traversePrepared_ insertUser users
271+ idResults <- traversePrepared insertUser (Only . userName <$> users)
272+ ids <- traverse (fmap fromOnly . getRow 0) idResults
273+ traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
269 usersResult <- runQuery getUsers
274 usersResult <- runQuery getUsers
270 usersRows <- getRows usersResult
275 usersRows <- getRows usersResult
271− liftIO $ print (usersRows :: [User])
276+ liftBase $ print (usersRows :: [User])
272in
277in
273− withConnection "host=localhost port=5432 dbname=exampledb" $
278+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
274 define setup
279 define setup
275 & pqThen session
280 & pqThen session
276 & pqThen (define teardown)
281 & pqThen (define teardown)
277:}
282:}
278[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
283[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
279−-}
280```
284```
RELEASE NOTES.md−837
@@ -1,842 +1,5 @@
1## RELEASE NOTES
1## RELEASE NOTES
2
2
3−### Version 0.5
4−
5−Version 0.5 makes a number of large changes and additions to Squeal.
6−I want to thank folks who contributed issues and pull requests;
7−Raveline, rimmington, ilyakooo0, chshersh, reygoch, and more.
8−
9−**Multi-schema support**
10−
11−Previous versions of Squeal only supported definitions in the "public"
12−schema. Squeal 0.5 adds support for multiple schemas with the new kind
13−
14−```Haskell
15−type SchemasType = [(Symbol,SchemaType)]
16−```
17−
18−In order to upgrade your queries, manipulations and definitions from
19−Squeal 0.4, you will have to apply the `Public` type family, which indicates
20−that your only schema is the "public" schema.
21−
22−```Haskell
23−-- Squeal 0.4
24−setup :: Definition '[] Schema
25−
26−-- Squeal 0.5
27−setup :: Definition (Public '[]) (Public Schema)
28−```
29−
30−You can create non-public schemas using `createSchema` and inversely
31−remove them using `dropSchema`. There is also an idempotent
32−`createSchemaIfNotExists`.
33−
34−In order to handle aliases which may refer to non-public schemas, Squeal 0.5
35−introduces `QualifiedAlias`es. A `QualifiedAlias` can be referred to using
36−the `(!)` operator from the `IsQualified` typeclass; but if you want to refer
37−to an alias from the "public" schema, you can continue to use a single
38−overloaded label, no need to write `#public ! #tab`, just write `#tab`.
39−
40−**Top-level statements**
41−
42−As a consequence of multi-schema support, common table expressions that
43−a `Query` or `Manipulation` may refer to had to be broken into a new parameter.
44−Additionally, `Query` gained another new parameter for its outer scope which
45−will be discussed in the next section.
46−
47−To simplify type signatures that you have to write for top-level queries
48−and manipulations, Squeal 0.5 introduces the `Query_` and `Manipulation_`
49−type families.
50−
51−```
52−type family Query_
53− (schemas :: SchemasType)
54− (parameters :: Type)
55− (row :: Type) where
56− Query_ schemas params row =
57− Query '[] '[] schemas (TuplePG params) (RowPG row)
58−```
59−
60−As you see, a top-level `Query_` has no outer scope and no common
61−table expressions in scope, they are empty `'[]`. Moreover,
62−its parameters and row parameters are now `Type`s, which are
63−converted to corresponding Postgres types using the `TuplePG`
64−and `RowPG` type families. This means you can write the type signatures
65−for your top-level statements using the Haskell types that you
66−intend to input and retrieve when running the statements. Similar
67−to `Query_`, there is a `Manipulation_` type, the only difference
68−being that a general `Manipulation` doesn't have an outer scope,
69−only a scope for common table expressions.
70−
71−**Subquery expressions**
72−
73−Previous versions of Squeal offered subquery expression support
74−but there were issues. The common use case of using the `IN` operator
75−from SQL was overly complex. There was a proliferation of subquery
76−functions to handle different comparison operators, each with two versions
77−for comparing `ALL` or `ANY` of the query rows. And, most confoundedly,
78−there was no way to support the `EXISTS` subquery because the "outer scope"
79−for a query was not available.
80−
81−Squeal adds an outer scope to the `Query` type.
82−
83−```Haskell
84−newtype Query
85− (outer :: FromType)
86− (commons :: FromType)
87− (schemas :: SchemasType)
88− (params :: [NullityType])
89− (row :: RowType)
90− = UnsafeQuery { renderQuery :: ByteString }
91−```
92−
93−This enables a well-typed `exists` function.
94−
95−```Haskell
96−exists
97− :: Query (Join outer from) commons schemas params row
98− -> Condition outer commons grp schemas params from
99−```
100−
101−The `in_` and `notIn` functions were simplified to handle the most
102−common use case of comparing to a list of values.
103−
104−```Haskell
105−in_
106− :: Expression outer commons grp schemas params from ty -- ^ expression
107− -> [Expression outer commons grp schemas params from ty]
108− -> Condition outer commons grp schemas params from
109−```
110−
111−Finally, general subquery comparisons were abstracted to work with
112−any comparison operators, using the `Operator` type which will be discussed in
113−the next section.
114−
115−```Haskell
116−subAll
117− :: Expression outer commons grp schemas params from ty1
118− -> Operator ty1 ty2 ('Null 'PGbool)
119− -> Query (Join outer from) commons schemas params '[col ::: ty2]
120− -> Condition outer commons grp schemas params from
121−
122−subAny
123− :: Expression outer commons grp schemas params from ty1
124− -> Operator ty1 ty2 ('Null 'PGbool)
125− -> Query (Join outer from) commons schemas params '[col ::: ty2]
126− -> Condition outer commons grp schemas params from
127−```
128−
129−**Expression RankNTypes**
130−
131−Squeal 0.5 introduces RankNType type synonyms for common expression patterns.
132−The simplest example is the `Expr` type, a type for "closed" expressions
133−that cannot reference any aliases or parameters.
134−
135−```Haskell
136−type Expr x
137− = forall outer commons grp schemas params from
138− . Expression outer commons grp schemas params from x
139−```
140−
141−There is also a function type `(-->)`, which is a subtype of the usual Haskell function
142−type `(->)`.
143−
144−```Haskell
145−type (-->) x y
146− = forall outer commons grp schemas params from
147− . Expression outer commons grp schemas params from x
148− -> Expression outer commons grp schemas params from y
149−```
150−
151−We saw in the subquery section that there is an `Operator` type.
152−
153−```Haskell
154−type Operator x1 x2 y
155− = forall outer commons grp schemas params from
156− . Expression outer commons grp schemas params from x1
157− -> Expression outer commons grp schemas params from x2
158− -> Expression outer commons grp schemas params from y
159−```
160−
161−There are also types `FunctionN` and `FunctionVar` for n-ary functions
162−and variadic functions.
163−
164−```
165−type FunctionN xs y
166− = forall outer commons grp schemas params from
167− . NP (Expression outer commons grp schemas params from) xs
168− -> Expression outer commons grp schemas params from y
169−```
170−
171−An n-ary function takes an `NP` list of `Expression`s as its argument.
172−Squeal 0.5 adds a helpful operator `(*:)`, to help scrap your `Nil`s.
173−You can construct an `NP` list now by using the operator `(:*)`,
174−until your last element, using `(*:)` there. For instance, the function
175−`atan2_` takes two arguments, `atan2_ (pi *: 2)`.
176−
177−**Selections**
178−
179−Previously, Squeal provided a couple versions of `SELECT` depending
180−on whether you wanted to select all columns of a unique table
181−in the from clause, i.e. `*`, all columns of a particular table
182−in the from clause, i.e. `.*`, or a list of columns from the from clause.
183−
184−Squeal 0.5 refactors this pattern into a `Selection` GADT type, allowing
185−for abstraction and combinations that were not possible before.
186−
187−```Haskell
188−data Selection outer commons grp schemas params from row where
189− Star
190− :: HasUnique tab from row
191− => Selection outer commons 'Ungrouped schemas params from row
192− DotStar
193− :: Has tab from row
194− => Alias tab
195− -> Selection outer commons 'Ungrouped schemas params from row
196− List
197− :: SListI row
198− => NP (Aliased (Expression outer commons grp schemas params from)) row
199− -> Selection outer commons grp schemas params from row
200− Over
201− :: SListI row
202− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row
203− -> WindowDefinition outer commons grp schemas params from
204− -> Selection outer commons grp schemas params from row
205− Also
206− :: Selection outer commons grp schemas params from right
207− -> Selection outer commons grp schemas params from left
208− -> Selection outer commons grp schemas params from (Join left right)
209−```
210−
211−In addition to the `Star`, `DotStar` and `List` constructors, there is an
212−`Also` constructor combinator, which enables users to combine `Selection`s.
213−Additionally, there is an `Over` constructor that is used to enable
214−window functions, described in the next section.
215−
216−To upgrade from Squeal 0.4, you will replace `selectStar` with `select Star`,
217−replace `selectDotStar #tab` with `select (DotStar #tab)`. The `List`
218−selection is such a common use case that there is a function `select_` which
219−automatically applies it, so to upgrade from Squeal 0.4, replace `select`
220−with `select_`. There are also independent `selectDistinct` and `selectDistinct_`
221−functions to filter out duplicate rows.
222−
223−**Query clauses**
224−
225−Previously, Squeal provided a couple versions of `INSERT` depending
226−on whether you wanted to insert `VALUES` or a query.
227−
228−Squeal 0.5 refactors this pattern into a `QueryClause` GADT.
229−
230−```
231−-- Squeal 0.4
232−insertRow_ #tab (Set 2 `as` #col1 :* Default `as` #col2)
233−insertQuery_ #tab (selectStar (from (table #other_tab)))
234−
235−-- Squeal 0.5
236−insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))
237−insertInto_ #tab (Subquery (select Star (from (table #other_tab))))
238−```
239−
240−**Window functions and aggregation**
241−
242−Previous versions of Squeal provided no support for window functions.
243−Squeal 0.5 adds support for window functions. We saw `Over` in the
244−previous section.
245−
246−```Haskell
247−Over
248− :: SListI row
249− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row
250− -> WindowDefinition outer commons grp schemas params from
251− -> Selection outer commons grp schemas params from row
252−```
253−
254−`Over` combines window functions with window definitions. A `WindowDefinition`
255−is constructed using the `partitionBy` function, optionally with an `orderBy`
256−clause. For example,
257−
258−```Haskell
259−query :: Query_ (Public Schema) () (Row Int32 Int32)
260−query = select
261− (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))
262− (from (table #tab))
263−```
264−
265−Here the `rank` function is a `WindowFunction`
266−
267−```Haskell
268−rank :: WinFun0 ('NotNull 'PGint8)
269−rank = UnsafeWindowFunction "rank()"
270−```
271−
272−`WinFun0` is a RankNType, like `Expr` was, used for no argument window functions.
273−Similarly, there are also `WinFun1` and `WinFunN` types for
274−window functions and n-ary window functions.
275−
276−In order to use the same syntax for certain window functions and aggregate functions,
277−a new typeclass `Aggregate` was introduced. So for instance, `sum_` can be
278−either a `Distinction` `Expression` or a `WindowFunction`, used either with
279−a `groupBy` or with a `partitionBy` in the appropriate way.
280−
281−```
282−data Distinction (expr :: kind -> Type) (ty :: kind)
283− = All (expr ty)
284− | Distinct (expr ty)
285−```
286−
287−Aggregate functions can be run over all rows or only over distinct rows,
288−while window functions bear no such distinction.
289−
290−**Migrations**
291−
292−Thanks to [https://github.com/Raveline](Raveline) Squeal 0.5 introduces
293−a function `defaultMain` to easily create a command line program to
294−run or rewind your migrations.
295−
296−Previously, Squeal's migrations were impure, allowing in addition to
297−running `Definition`s to run arbitrary `IO` operations, such as inserting
298−data into the database or printing out status messages. In order to
299−provide compatibility with other migration systems, Squeal 0.5 introduces
300−pure migrations, that is migrations that are only `Definition`s.
301−
302−```Haskell
303−data Migration p schemas0 schemas1 = Migration
304− { name :: Text -- ^ The `name` of a `Migration`.
305− -- Each `name` in a `Migration` should be unique.
306− , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.
307− , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.
308− } deriving (GHC.Generic)
309−```
310−
311−A pure migration is a `Migration Definition`, a pair of inverse
312−`Definition`s with a unique name. To recover impure migrations, Squeal 0.5
313−introduces the `Terminally` type.
314−
315−```Haskell
316−newtype Terminally trans monad x0 x1 = Terminally
317− { runTerminally :: trans x0 x1 monad () }
318−```
319−
320−`Terminally` applies the indexed monad transformer and the monad it transforms
321−to the unit type `()`, thereby turning an indexed monad into a `Category`. An
322−impure migration is a `Migration (Terminally PQ IO)`. You can always cast
323−a pure migration into an impure migration with the functor, `pureMigration`.
324−
325−```Haskell
326−pureMigration
327− :: Migration Definition schemas0 schemas1
328− -> Migration (Terminally PQ IO) schemas0 schemas1
329−```
330−
331−To run either pure or impure migrations, Squeal 0.5 introduces
332−a typeclass, `Migratory`.
333−
334−```
335−class Category p => Migratory p where
336−
337− migrateUp
338− :: AlignedList (Migration p) schemas0 schemas1
339− -> PQ schemas0 schemas1 IO ()
340−
341− migrateDown
342− :: AlignedList (Migration p) schemas0 schemas1
343− -> PQ schemas1 schemas0 IO ()
344−```
345−
346−The signatures of `migrateUp` and `migrateDown` have been changed
347−to make them easier to compose with other `PQ` actions.
348−
349−**Transactions**
350−
351−You can now run transactions `ephemerally`, guaranteed to roll back,
352−but return the result or throw the exception that the transaction
353−would have generated. This is useful for testing. You can also
354−`transactionallyRetry` computations, retrying the transaction if
355−a [serialization failure](https://www.postgresql.org/docs/11/transaction-iso.html#XACT-REPEATABLE-READ) occurs.
356−
357−**Types**
358−
359−Squeal now supports money via a `Money` Haskell `Type` and a `'PGmoney`
360−`PGType`. Squeal 0.5 also adds support for creating domain types
361−with `createDomain`.
362−
363−**Time**
364−
365−Squeal 0.5 adds support for new functions; `now`, `makeDate`, `makeTime`,
366−, `makeTimestamp`, and `makeTimestamptz`, a function `interval_` for
367−constructing time intervals out multiples of `TimeUnit`s, and a new
368−`TimeOp` class, defining affine space operators for time types and their
369−differences.
370−
371−**Literals**
372−
373−Squeal allows you to include Haskell values in your statements using
374−out of line `parameter`s, but often you want to include them inline,
375−as a SQL `literal`. Squeal 0.5 enables this using the `Literal` class.
376−
377−**Set returning functions**
378−
379−Squeal 0.5 adds support for set returning functions such as `unnest`,
380−with the `RankNType` `SetOfFunction`, which can be used as as a `FromClause`.
381−
382−**Text search**
383−
384−Squeal 0.5 adds extensive support for text search types, functions and operators.
385−
386−**Much more**
387−
388−Lots more changes went into and under the hood of the new version.
389−The `Expression` module was split into coherent submodules since it
390−had grown to immense proportions. New modules `Alias`, `PG` and `List`
391−were added to relieve some of the burden that the `Schema` module
392−had been carrying. Rendering has been better unified with a new
393−`RenderSQL` typeclass. Type level list concatenation with the `Additional`
394−typeclass has been added. `Manipulation`s `update` and `delete`
395−were upgraded, so you can leave out fields you don't want to update and
396−use `USING` clauses in deletes. Upserts which were previously broken
397−now work. The `IO` typeclass hierarchy was changed from `MonadBase`
398−and `MonadBaseControl` to `MonadIO` and `MonadUnliftIO`. A new
399−`withRecursive` `Manipulation` was added. `SquealException`s were
400−refactored and a `trySqueal` function added. Arrays were refactored.
401−And there was probably more I've forgotten.
402−
403−### Version 0.4
404−
405−Version 0.4 strengthens Squeal's type system, adds
406−support for multidimensional arrays, improves support
407−for container type, improves `with` statements,
408−improves runtime exceptions, accomodates SQL's three-valued logic,
409−adds subquery expressions, and adds table and view type expressions.
410−
411−**Types**
412−
413−Squeal 0.4 renames some kinds to aid intuition:
414−
415−```Haskell
416−type RowType = [(Symbol, NullityType)] -- previously RelationType
417−type FromType = [(Symbol, RowType)] -- previously RelationsType
418−```
419−
420−Null safety for array and composite types is gained by having the base
421−type of an array be a `NullityType` and the base type of a composite
422−a `RowType`.
423−
424−```Haskell
425−data PGType
426− = ..
427− | PGvararray NullityType
428− | PGfixarray Nat NullityType
429− | PGcomposite RowType
430−```
431−
432−Squeal embeds Postgres types into Haskell using data kinds and type-in-type:
433−
434−```Haskell
435−data PGType = PGbool | ..
436−data NullityType = Null PGType | NotNull PGType
437−type RowType = [(Symbol, NullityType)] -- previously RelationType
438−type FromType = [(Symbol, RowType)] -- previously RelationsType
439−```
440−
441−In another sense, we can embed Haskell types
442−into Postgres types by providing type families:
443−
444−```Haskell
445−type family PG (hask :: Type) :: PGType
446−type family NullPG (hask :: Type) :: NullityType
447−type family TuplePG (hask :: Type) :: [NullityType]
448−type family RowPG (hask :: Type) :: RowType
449−```
450−
451−Let's look at these one by one.
452−
453−`PG` was introduced in Squeal 0.3. It was a closed type family that
454−associates some Haskell types to their obvious corresponding Postgres
455−types like `PG Double = 'PGfloat8`. It only worked on base types,
456−no arrays or composites. Squeal 0.4 extends it to
457−such container types and makes it an open type family so that
458−users can make their own type instances.
459−
460−`NullPG` had a different name before but it does the obvious
461−thing for Haskell with `Maybe`s:
462−
463−```Haskell
464−type family NullPG hask where
465− NullPG (Maybe hask) = 'Null (PG hask)
466− NullPG hask = 'NotNull (PG hask)
467−```
468−
469−`TuplePG` uses generics to turn tuple types (including records)
470−into lists of `NullityType`s in the logical way, e.g.
471−`TuplePG (Bool, Day) = '[ 'PGbool, 'PGdate]`.
472−
473−`RowPG` also uses generics to turn record types into a `RowType` in the logical way, e.g.
474−
475−```Haskell
476−>>> data Person = Person { name :: Text, age :: Int32 } deriving GHC.Generic
477−>>> instance SOP.Generic Person
478−>>> instance SOP.HasDatatypeInfo Person
479−>>> :kind! TuplePG Person
480−TuplePG Person :: [NullityType]
481−= '['NotNull 'PGtext, 'NotNull 'PGint4]
482−>>> :kind! RowPG Person
483−RowPG Person :: [(Symbol, NullityType)]
484−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]
485−```
486−
487−We've already seen a hint of why these types are useful in one construction
488−from Squeal 0.3. Creating composite types in Postgres directly from a Haskell
489−record type essentially uses `RowPG`. Another important use is in simplifying
490−the type signatures for a `Query` or `Manipulation`. Very often, you will have
491−a tuple type corresponding to the parameters and a record type corresponding
492−to the returned columns of a `Query` or `Manipulation`. Instead of writing
493−boilerplate signature you can reuse these with the help of `TuplePG` and `RowPG`
494−
495−For instance:
496−
497−```Haskell
498−>>> :{
499−let
500− query :: Query '["user" ::: 'View (RowPG Person)] (TuplePG (Only Int32)) (RowPG Person)
501− query = selectStar (from (view #user) & where_ (#age .> param @1))
502−:}
503−```
504−
505−**Arrays**
506−
507−In addition to being able to encode and decode basic Haskell types
508−like `Int16` and `Text`, Squeal 0.4 permits you to encode and decode Haskell types to
509−Postgres array types. The `Vector` type corresponds to to variable length arrays.
510−And thanks to an idea from [Mike Ledger](https://github.com/mikeplus64),
511−homogeneous tuples correspond to fixed length arrays. We can even
512−create multi-dimensional fixed length arrays. Let's see an example.
513−
514−```Haskell
515−>>> :{
516−data Row = Row
517− { col1 :: Vector Int16
518− , col2 :: (Maybe Int16,Maybe Int16)
519− , col3 :: ((Int16,Int16),(Int16,Int16),(Int16,Int16))
520− } deriving (Eq, GHC.Generic)
521−:}
522−
523−>>> instance Generic Row
524−>>> instance HasDatatypeInfo Row
525−```
526−
527−Define a simple round trip query.
528−
529−```Haskell
530−>>> :{
531−let
532− roundTrip :: Query '[] (TuplePG Row) (RowPG Row)
533− roundTrip = values_ $
534− parameter @1 (int2 & vararray) `as` #col1 :*
535− parameter @2 (int2 & fixarray @2) `as` #col2 :*
536− parameter @3 (int2 & fixarray @2 & fixarray @3) `as` #col3
537−:}
538−
539−>>> :set -XOverloadedLists
540−>>> let input = Row [1,2] (Just 1,Nothing) ((1,2),(3,4),(5,6))
541−>>> :{
542−void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
543− result <- runQueryParams roundTrip input
544− Just output <- firstRow result
545− liftBase . print $ input == output
546−:}
547−True
548−```
549−
550−**Containers**
551−
552−Squeal aims to provide a correspondence between Haskell types and Postgres types.
553−In particular, Haskell ADTs with nullary constructors can correspond to
554−Postgres enum types and Haskell record types can correspond to Postgres
555−composite types. However, it's not always obvious that that's how a user
556−will choose to store values of those types. So Squeal 0.4 introduces newtypes
557−whose purpose is to specify how a user wants to store values of a type.
558−
559−```Haskell
560−newtype Json hask = Json {getJson :: hask}
561−newtype Jsonb hask = Jsonb {getJsonb :: hask}
562−newtype Composite record = Composite {getComposite :: record}
563−newtype Enumerated enum = Enumerated {getEnumerated :: enum}
564−```
565−
566−Let's see an example:
567−
568−```Haskell
569−>>> data Schwarma = Beef | Lamb | Chicken deriving (Eq, Show, GHC.Generic)
570−>>> instance SOP.Generic Schwarma
571−>>> instance SOP.HasDatatypeInfo Schwarma
572−>>>
573−>>> data Person = Person {name :: Text, age :: Int32} deriving (Eq, Show, GHC.Generic)
574−>>> instance SOP.Generic Person
575−>>> instance SOP.HasDatatypeInfo Person
576−>>> instance Aeson.FromJSON Person
577−>>> instance Aeson.ToJSON Person
578−```
579−
580−We can create the equivalent Postgres types directly from their Haskell types.
581−
582−```Haskell
583−>>> :{
584−type Schema =
585− '[ "schwarma" ::: 'Typedef (PG (Enumerated Schwarma))
586− , "person" ::: 'Typedef (PG (Composite Person))
587− ]
588−:}
589−
590−>>> :{
591−let
592− setup :: Definition '[] Schema
593− setup =
594− createTypeEnumFrom @Schwarma #schwarma >>>
595− createTypeCompositeFrom @Person #person
596−:}
597−```
598−
599−Let's demonstrate how to associate our Haskell types `Schwarma` and `Person`
600−with enumerated, composite or json types in Postgres. First create a Haskell
601−`Row` type using the `Enumerated`, `Composite` and `Json` newtypes as fields.
602−
603−```Haskell
604−>>> :{
605−data Row = Row
606− { schwarma :: Enumerated Schwarma
607− , person1 :: Composite Person
608− , person2 :: Json Person
609− } deriving (Eq, GHC.Generic)
610−:}
611−
612−>>> instance Generic Row
613−>>> instance HasDatatypeInfo Row
614−>>> :{
615−let
616− input = Row
617− (Enumerated Chicken)
618− (Composite (Person "Faisal" 24))
619− (Json (Person "Ahmad" 48))
620−:}
621−```
622−
623−Once again, define a round trip query.
624−
625−```Haskell
626−>>> :{
627−let
628− roundTrip :: Query Schema (TuplePG Row) (RowPG Row)
629− roundTrip = values_ $
630− parameter @1 (typedef #schwarma) `as` #schwarma :*
631− parameter @2 (typedef #person) `as` #person1 :*
632− parameter @3 json `as` #person2
633−:}
634−```
635−
636−Finally, we can drop our type definitions.
637−
638−```Haskell
639−>>> :{
640−let
641− teardown :: Definition Schema '[]
642− teardown = dropType #schwarma >>> dropType #person
643−:}
644−```
645−
646−Now let's run it.
647−
648−```Haskell
649−>>> :{
650−let
651− session = do
652− result <- runQueryParams roundTrip input
653− Just output <- firstRow result
654− liftBase . print $ input == output
655−in
656− void . withConnection "host=localhost port=5432 dbname=exampledb" $
657− define setup
658− & pqThen session
659− & pqThen (define teardown)
660−:}
661−True
662−```
663−
664−**With**
665−
666−Squeal 0.3 supported WITH statements but there's a couple problems with them.
667−Here's the type signature for `with` in Squeal 0.3.
668−
669−```Haskell
670−with
671− :: SOP.SListI commons
672− => NP (Aliased (Manipulation schema params)) (common ': commons)
673− -- ^ common table expressions
674− -> Manipulation (With (common ': commons) schema) params results
675− -> Manipulation schema params results
676−```
677−
678−The first problem is that `with` only works with `Manipulations`.
679−It can work on `Query`s by using `queryStatement` but it still will
680−return a `Manipulation`. We can fix this issue by making `with` a
681−method of a type class with instances for both `Query` and `Manipulation`.
682−
683−The second problem is that all the common table expressions
684−refer the base schema, whereas in SQL, each subsequent CTE can
685−refer to previous CTEs as well. But this can be fixed! First define a datatype:
686−
687−```Haskell
688−data CommonTableExpression statement params schema0 schema1 where
689− CommonTableExpression
690− :: Aliased (statement schema params) (alias ::: cte)
691− -> CommonTableExpression statement params schema (alias ::: 'View cte ': schema)
692−```
693−
694−It's just a wrapper around an aliased statement, where the statement
695−could be either a `Query` or `Manipulation`, but it augments the schema
696−by adding a view to it. It almost looks like a morphism between schemas
697−but there is no way yet to compose them. Luckily, Squeal already has
698−a datatype for this, which is used for migrations, the `AlignedList`
699−type which is really the "free category". So we can then define a `With` type class:
700−
701−```Haskell
702−class With statement where
703− with
704− :: AlignedList (CommonTableExpression statement params) schema0 schema1
705− -> statement schema1 params row
706− -> statement schema0 params row
707−```
708−
709−By giving `Aliasable` instances to CTEs and aligned singleton lists of CTEs (i.e. scrap-your-nils), we get a nice syntax for WITH statements in Squeal.
710−
711−Here's an example of using `with` for a `Query` and a `Manipulation`:
712−
713−```Haskell
714−>>> :{
715−let
716− query :: Query
717− '[ "t1" ::: 'View
718− '[ "c1" ::: 'NotNull 'PGtext
719− , "c2" ::: 'NotNull 'PGtext] ]
720− '[]
721− '[ "c1" ::: 'NotNull 'PGtext
722− , "c2" ::: 'NotNull 'PGtext ]
723− query = with (
724− selectStar (from (view #t1)) `as` #t2 :>>
725− selectStar (from (view #t2)) `as` #t3
726− ) (selectStar (from (view #t3)))
727−in printSQL query
728−:}
729−WITH "t2" AS (SELECT * FROM "t1" AS "t1"), "t3" AS (SELECT * FROM "t2" AS "t2") SELECT * FROM "t3" AS "t3"
730−
731−>>> type ProductsTable = '[] :=> '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]
732−
733−>>> :{
734−let
735− manipulation :: Manipulation
736− '[ "products" ::: 'Table ProductsTable
737− , "products_deleted" ::: 'Table ProductsTable
738− ] '[ 'NotNull 'PGdate] '[]
739− manipulation = with
740− (deleteFrom #products (#date .< param @1) ReturningStar `as` #deleted_rows)
741− (insertQuery_ #products_deleted (selectStar (from (view (#deleted_rows `as` #t)))))
742−in printSQL manipulation
743−:}
744−WITH "deleted_rows" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "deleted_rows" AS "t"
745−```
746−
747−**Three Valued Logic**
748−
749−In previous versions of Squeal, conditions followed classical two valued logic
750−of `true` and `false`.
751−
752−```Haskell
753−-- Squeal 0.3
754−type Condition schema from grouping params =
755− Expression schema from grouping params ('NotNull 'PGbool)
756−```
757−
758−I had thought that three valued logic, which is what SQL uses, was confusing.
759−However, multiple users reported being confused at being forced to do `NULL`
760−handling, particularly in their left joins. Since the original motivation
761−of being less confusing evaporated I decided to switch to three valued logic
762−of `true`, `false` and `null_`.
763−
764−```Haskell
765−-- Squeal 0.4
766−type Condition schema from grouping params =
767− Expression schema from grouping params ('Null 'PGbool)
768−```
769−
770−**Subquery Expressions**
771−
772−Squeal 0.4 adds support for subquery expressions such as `IN` and `op ANY/ALL`.
773−
774−**Row Types**
775−
776−Squeal 0.4 adds functions to define type expressions from tables and views
777−and a type expression for user defined types, `typetable`, `typeview` and
778−`typedef`.
779−
780−**Runtime Exceptions**
781−
782−Squeal now has an exception type which gives details on the sort of error
783−encountered and handler functions.
784−
785−```Haskell
786−data SquealException
787− = PQException
788− { sqlExecStatus :: LibPQ.ExecStatus
789− , sqlStateCode :: Maybe ByteString
790− -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html
791− , sqlErrorMessage :: Maybe ByteString
792− }
793− | ResultException Text
794− | ParseException Text
795− deriving (Eq, Show)
796−instance Exception SquealException
797−
798−catchSqueal
799− :: MonadBaseControl IO io
800− => io a
801− -> (SquealException -> io a) -- ^ handler
802− -> io a
803−
804−handleSqueal
805− :: MonadBaseControl IO io
806− => (SquealException -> io a) -- ^ handler
807− -> io a -> io a
808−```
809−
810−**Additional Changes**
811−
812−Squeal 0.4 adds `field` and `index` functions to get components of composite
813−and array expressions.
814−
815−Squeal 0.4 adds a dependency on `records-sop` to offload a lot of boilerplate
816−type family logic that was needed for `RowPG`.
817−
818−The above changes required major and minor changes to Squeal DSL functions.
819−Please consult the documentation.
820−
821−### Version 0.3.2 - August 4, 2018
822−
823−Version 0.3.2 features extensive support for `JSON` functionality with
824−more than 50 new functions.
825−This work is entirely due to [Mike Ledger](https://github.com/mikeplus64)
826−who has been making terrific contributions to Squeal. Thanks!
827−We also got some examples in the documentation for pools submitted by
828−[Raveline](https://github.com/Raveline). I'm so pleased to be
829−getting pull requests and issue submissions from you all!
830−
831−### Version 0.3.1 - July 7, 2018
832−
833−Version 0.3.1 of Squeal enables the "Scrap your Nils" trick for
834−heterogeneous lists of `Alias`es, `Aliased` expressions, `PGlabel`s and `By`s
835−with the typeclasses `IsLabel`, `IsQualified`, `IsPGlabel`,
836−and the new `Aliasable` typeclass, to eliminate all need of using `Nil` in a list.
837−There were a couple minor name changes, i.e. the function `group` was renamed to `groupBy`.
838−Please consult the documentation.
839−
840### Version 0.3 - June 26, 2018
3### Version 0.3 - June 26, 2018
841
4
842Version 0.3 of Squeal adds views as well as composite and enumerated types to Squeal.
5Version 0.3 of Squeal adds views as well as composite and enumerated types to Squeal.
scrap-your-nils.mddeleted−60
@@ -1,60 +0,0 @@
1−## Scrap your Nils
2−
3−One of the most useful types I've come across in Haskell is the type of
4−"heterogeneous lists". This is the same as the [Rec](http://hackage.haskell.org/package/vinyl-0.8.1.1/docs/Data-Vinyl-Core.html)
5−datatype from the [vinyl](http://hackage.haskell.org/package/vinyl) library.
6−It's also the same as the [NP](http://hackage.haskell.org/package/generics-sop-0.3.2.0/docs/Generics-SOP-NP.html)
7−datatype from the [generics-sop](http://hackage.haskell.org/package/generics-sop) library.
8−Squeal makes heavy use of this type.
9−
10−```Haskell
11−>>> import Generics.SOP (NP(..))
12−>>> :i NP
13−type role NP representational nominal
14−data NP (a :: k -> *) (b :: [k]) where
15− Nil :: forall k (a :: k -> *). NP a '[]
16− (:*) :: forall k (a :: k -> *) (x :: k) (xs :: [k]).
17− (a x) -> (NP a xs) -> NP a (x : xs)
18− -- Defined in ‘Generics.SOP.NP’
19−```
20−
21−This type allows us to construct "product" types, where the types of the individual
22−"terms" are hosted at the type level.
23−
24−```Haskell
25−>>> :set -XDataKinds
26−>>> import Generics.SOP (I(..))
27−>>> let example = I "foo" :* I pi :* Nil :: NP I '[String, Double]
28−>>> example
29−I "foo" :* I 3.141592653589793 :* Nil
30−```
31−
32−One thing Squeal uses `NP` for is to form lists of aliases,
33−using GHC's `OverloadedLabels` extension, hosting the names
34−of the aliases themselves at the type level.
35−
36−```Haskell
37−>>> :set -XKindSignatures -XOverloadedLabels -XFlexibleInstances -XMultiParamTypeClasses
38−>>> import GHC.TypeLits
39−>>> import GHC.OverloadedLabels
40−>>> data Alias (alias :: Symbol) = Alias deriving (Eq,Ord,Show)
41−>>> instance IsLabel label (Alias label) where fromLabel = Alias
42−>>> let aliases = #foo :* #bar :* Nil :: NP Alias '["foo", "bar"]
43−```
44−
45−However, it's very ugly to have to end every list with `:* Nil`.
46−When I announced the release of Squeal, people rightly [complained](https://www.reddit.com/r/haskell/comments/6yr5v6/announcing_squeal_a_deep_embedding_of_sql_in/dmq8vvn)
47−about the syntactic noise. Luckily, there's a neat trick we can use to get rid of it.
48−Making an `IsLabel` instance not only for elements of our list
49−but also for lists of length 1, we can ask GHC to interpret
50−the last label as a list.
51−
52−```Haskell
53−>>> instance IsLabel label (NP Alias '[label]) where fromLabel = Alias :* Nil
54−>>> let aliases' = #foo :* #bar :: NP Alias '["foo", "bar"]
55−```
56−
57−Version 0.3.1 of Squeal enables the "Scrap your Nils" trick for
58−heterogeneous lists of `Alias`es, `Aliased` expressions, `PGlabel`s and `By`s
59−with the typeclasses `IsLabel`, `IsQualified`, `IsPGlabel`,
60−and the new `Aliasable` typeclass, to eliminate all need of using `Nil` in a list.
squeal-postgresql/exe/Example.hs+49−46
@@ -11,7 +11,8 @@
11
11
12module Main (main, main2) where
12module Main (main, main2) where
13
13
14−import Control.Monad.IO.Class (MonadIO (..))
14+import Control.Monad (void)
15+import Control.Monad.Base (liftBase, MonadBase)
15import Data.Int (Int16, Int32)
16import Data.Int (Int16, Int32)
16import Data.Monoid ((<>))
17import Data.Monoid ((<>))
17import Data.Text (Text)
18import Data.Text (Text)
@@ -28,7 +29,7 @@ type Schema =
28 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
29 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
29 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
30 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
30 , "name" ::: 'NoDef :=> 'NotNull 'PGtext
31 , "name" ::: 'NoDef :=> 'NotNull 'PGtext
31− , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray ('Null 'PGint2))
32+ , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray 'PGint2)
32 ])
33 ])
33 , "emails" ::: 'Table (
34 , "emails" ::: 'Table (
34 '[ "pk_emails" ::: 'PrimaryKey '["id"]
35 '[ "pk_emails" ::: 'PrimaryKey '["id"]
@@ -38,70 +39,72 @@ type Schema =
38 , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
39 , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
39 , "email" ::: 'NoDef :=> 'Null 'PGtext
40 , "email" ::: 'NoDef :=> 'Null 'PGtext
40 ])
41 ])
41− , "positive" ::: 'Typedef 'PGfloat4
42 ]
42 ]
43
43
44−type Schemas = Public Schema
45−
46−setup :: Definition (Public '[]) Schemas
44+setup :: Definition '[] Schema
47−setup =
45+setup =
48 createTable #users
46 createTable #users
49− ( serial `as` #id :*
47+ ( serial `As` #id :*
50− (text & notNullable) `as` #name :*
48+ (text & notNullable) `As` #name :*
51− (vararray int2 & notNullable) `as` #vec )
49+ (vararray int2 & notNullable) `As` #vec :* Nil )
52− ( primaryKey #id `as` #pk_users )
50+ ( primaryKey #id `As` #pk_users :* Nil )
53 >>>
51 >>>
54 createTable #emails
52 createTable #emails
55− ( serial `as` #id :*
53+ ( serial `As` #id :*
56− hask @Int32 `as` #user_id :*
54+ (int & notNullable) `As` #user_id :*
57− hask @(Maybe Text) `as` #email )
55+ (text & nullable) `As` #email :* Nil )
58− ( primaryKey #id `as` #pk_emails :*
56+ ( primaryKey #id `As` #pk_emails :*
59 foreignKey #user_id #users #id
57 foreignKey #user_id #users #id
60− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
58+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
61− >>>
59+
62− createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
63−
64−teardown :: Definition Schemas (Public '[])
60+teardown :: Definition Schema '[]
65−teardown = dropType #positive >>> dropTable #emails >>> dropTable #users
61+teardown = dropTable #emails >>> dropTable #users
66−
62+
67−insertUser :: Manipulation_ Schemas (Text, VarArray (Vector (Maybe Int16))) (Only Int32)
63+insertUser :: Manipulation Schema '[ 'NotNull 'PGtext, 'NotNull ('PGvararray 'PGint2)]
64+ '[ "fromOnly" ::: 'NotNull 'PGint4 ]
68−insertUser = insertInto #users
65+insertUser = insertRows #users
69− (Values_ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec))
66+ (Default `As` #id :* Set (param @1) `As` #name :* Set (param @2) `As` #vec :* Nil) []
70− (OnConflict (OnConstraint #pk_users) DoNothing) (Returning_ (#id `as` #fromOnly))
67+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))
71−
68+
72−insertEmail :: Manipulation_ Schemas (Int32, Maybe Text) ()
69+insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
73−insertEmail = insertInto_ #emails
70+insertEmail = insertRows #emails
71+ ( Default `As` #id :*
74− (Values_ (Default `as` #id :* Set (param @1) `as` #user_id :* Set (param @2) `as` #email))
72+ Set (param @1) `As` #user_id :*
75−
73+ Set (param @2) `As` #email :* Nil ) []
76−getUsers :: Query_ Schemas () User
74+ OnConflictDoNothing (Returning Nil)
75+
76+getUsers :: Query Schema '[]
77+ '[ "userName" ::: 'NotNull 'PGtext
78+ , "userEmail" ::: 'Null 'PGtext
79+ , "userVec" ::: 'NotNull ('PGvararray 'PGint2)]
77−getUsers = select_
80+getUsers = select
78− (#u ! #name `as` #userName :* #e ! #email `as` #userEmail :* #u ! #vec `as` #userVec)
81+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* #u ! #vec `As` #userVec :* Nil)
79− ( from (table (#users `as` #u)
82+ ( from (table (#users `As` #u)
80− & innerJoin (table (#emails `as` #e))
83+ & innerJoin (table (#emails `As` #e))
81 (#u ! #id .== #e ! #user_id)) )
84 (#u ! #id .== #e ! #user_id)) )
82
85
83−data User = User { userName :: Text, userEmail :: Maybe Text, userVec :: VarArray (Vector (Maybe Int16)) }
86+data User = User { userName :: Text, userEmail :: Maybe Text, userVec :: Vector (Maybe Int16) }
84 deriving (Show, GHC.Generic)
87 deriving (Show, GHC.Generic)
85instance SOP.Generic User
88instance SOP.Generic User
86instance SOP.HasDatatypeInfo User
89instance SOP.HasDatatypeInfo User
87
90
88users :: [User]
91users :: [User]
89−users =
92+users =
90− [ User "Alice" (Just "alice@gmail.com") (VarArray [Nothing, Just 1])
93+ [ User "Alice" (Just "alice@gmail.com") [Nothing, Just 1]
91− , User "Bob" Nothing (VarArray [Just 2, Nothing])
94+ , User "Bob" Nothing [Just 2, Nothing]
92− , User "Carole" (Just "carole@hotmail.com") (VarArray [Just 3])
95+ , User "Carole" (Just "carole@hotmail.com") [Just 3]
93 ]
96 ]
94
97
95−session :: (MonadIO pq, MonadPQ Schemas pq) => pq ()
98+session :: (MonadBase IO pq, MonadPQ Schema pq) => pq ()
96session = do
99session = do
97− liftIO $ Char8.putStrLn "manipulating"
100+ liftBase $ Char8.putStrLn "manipulating"
98 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])
101 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])
99 ids <- traverse (fmap fromOnly . getRow 0) idResults
102 ids <- traverse (fmap fromOnly . getRow 0) idResults
100 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
103 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
101− liftIO $ Char8.putStrLn "querying"
104+ liftBase $ Char8.putStrLn "querying"
102 usersResult <- runQuery getUsers
105 usersResult <- runQuery getUsers
103 usersRows <- getRows usersResult
106 usersRows <- getRows usersResult
104− liftIO $ print (usersRows :: [User])
107+ liftBase $ print (usersRows :: [User])
105
108
106main :: IO ()
109main :: IO ()
107main = do
110main = do
@@ -119,7 +122,7 @@ main = do
119
122
120main2 :: IO ()
123main2 :: IO ()
121main2 =
124main2 =
122− withConnection "host=localhost port=5432 dbname=exampledb" $
125+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
123 define setup
126 define setup
124 & pqThen session
127 & pqThen session
125 & pqThen (define teardown)
128 & pqThen (define teardown)
squeal-postgresql/squeal-postgresql.cabal+10−71
@@ -1,5 +1,5 @@
1name: squeal-postgresql
1name: squeal-postgresql
2−version: 0.5.1.0
2+version: 0.3.0.0
3synopsis: Squeal PostgreSQL Library
3synopsis: Squeal PostgreSQL Library
4description: Squeal is a type-safe embedding of PostgreSQL in Haskell
4description: Squeal is a type-safe embedding of PostgreSQL in Haskell
5homepage: https://github.com/morphismtech/squeal
5homepage: https://github.com/morphismtech/squeal
@@ -22,40 +22,12 @@ library
22 hs-source-dirs: src
22 hs-source-dirs: src
23 exposed-modules:
23 exposed-modules:
24 Squeal.PostgreSQL
24 Squeal.PostgreSQL
25− Squeal.PostgreSQL.Alias
26 Squeal.PostgreSQL.Binary
25 Squeal.PostgreSQL.Binary
27 Squeal.PostgreSQL.Definition
26 Squeal.PostgreSQL.Definition
28− Squeal.PostgreSQL.Definition.Function
29− Squeal.PostgreSQL.Definition.Index
30− Squeal.PostgreSQL.Definition.Table
31− Squeal.PostgreSQL.Definition.Table.Constraint
32− Squeal.PostgreSQL.Definition.Type
33− Squeal.PostgreSQL.Definition.Schema
34− Squeal.PostgreSQL.Definition.View
35 Squeal.PostgreSQL.Expression
27 Squeal.PostgreSQL.Expression
36− Squeal.PostgreSQL.Expression.Aggregate
37− Squeal.PostgreSQL.Expression.Collection
38− Squeal.PostgreSQL.Expression.Comparison
39− Squeal.PostgreSQL.Expression.Json
40− Squeal.PostgreSQL.Expression.Literal
41− Squeal.PostgreSQL.Expression.Logic
42− Squeal.PostgreSQL.Expression.Math
43− Squeal.PostgreSQL.Expression.Null
44− Squeal.PostgreSQL.Expression.Parameter
45− Squeal.PostgreSQL.Expression.Range
46− Squeal.PostgreSQL.Expression.Set
47− Squeal.PostgreSQL.Expression.Sort
48− Squeal.PostgreSQL.Expression.Subquery
49− Squeal.PostgreSQL.Expression.Text
50− Squeal.PostgreSQL.Expression.TextSearch
51− Squeal.PostgreSQL.Expression.Time
52− Squeal.PostgreSQL.Expression.Type
53− Squeal.PostgreSQL.Expression.Window
54− Squeal.PostgreSQL.List
55 Squeal.PostgreSQL.Manipulation
28 Squeal.PostgreSQL.Manipulation
56 Squeal.PostgreSQL.Migration
29 Squeal.PostgreSQL.Migration
57 Squeal.PostgreSQL.Pool
30 Squeal.PostgreSQL.Pool
58− Squeal.PostgreSQL.PG
59 Squeal.PostgreSQL.PQ
31 Squeal.PostgreSQL.PQ
60 Squeal.PostgreSQL.Render
32 Squeal.PostgreSQL.Render
61 Squeal.PostgreSQL.Query
33 Squeal.PostgreSQL.Query
@@ -65,73 +37,39 @@ library
65 ghc-options: -Wall
37 ghc-options: -Wall
66 build-depends:
38 build-depends:
67 aeson >= 1.2.4.0
39 aeson >= 1.2.4.0
68− , base >= 4.11.1.0 && < 5.0
40+ , base >= 4.10.1.0 && < 5.0
69 , binary-parser >= 0.5.5
41 , binary-parser >= 0.5.5
70 , bytestring >= 0.10.8.2
42 , bytestring >= 0.10.8.2
71 , bytestring-strict-builder >= 0.4.5
43 , bytestring-strict-builder >= 0.4.5
72 , deepseq >= 1.4.3.0
44 , deepseq >= 1.4.3.0
73− , free-categories >= 0.1.0.0
74− , generics-sop >= 0.3.2.0 && < 0.5.0.0
45+ , generics-sop >= 0.3.2.0
46+ , lifted-base >= 0.2.3.12
75 , mmorph >= 1.1.1
47 , mmorph >= 1.1.1
48+ , monad-control >= 1.0.2.3
76 , mtl >= 2.2.2
49 , mtl >= 2.2.2
77 , network-ip >= 0.3.0.2
50 , network-ip >= 0.3.0.2
78 , postgresql-binary >= 0.12.1
51 , postgresql-binary >= 0.12.1
79 , postgresql-libpq >= 0.9.4.1
52 , postgresql-libpq >= 0.9.4.1
80− , records-sop >= 0.1.0.0
81 , resource-pool >= 0.2.3.2
53 , resource-pool >= 0.2.3.2
82 , scientific >= 0.3.5.3
54 , scientific >= 0.3.5.3
83 , text >= 1.2.3.0
55 , text >= 1.2.3.0
84 , time >= 1.8.0.2
56 , time >= 1.8.0.2
85 , transformers >= 0.5.2.0
57 , transformers >= 0.5.2.0
86− , unliftio >= 0.2.10
58+ , transformers-base >= 0.4.4
87− , unliftio-pool >= 0.2.1.0
88 , uuid-types >= 1.0.3
59 , uuid-types >= 1.0.3
89 , vector >= 0.12.0.1
60 , vector >= 0.12.0.1
90
61
91−test-suite doctest
62+test-suite squeal-postgresql-doctest
92 default-language: Haskell2010
63 default-language: Haskell2010
93 type: exitcode-stdio-1.0
64 type: exitcode-stdio-1.0
94 hs-source-dirs: test
65 hs-source-dirs: test
95 ghc-options: -Wall
66 ghc-options: -Wall
96− main-is: Doc.hs
67+ main-is: DocTest.hs
97 build-depends:
68 build-depends:
98 base >= 4.10.0.0
69 base >= 4.10.0.0
99 , doctest >= 0.11.4
70 , doctest >= 0.11.4
100− , squeal-postgresql
101−
102−test-suite properties
103− default-language: Haskell2010
104− type: exitcode-stdio-1.0
105− hs-source-dirs: test
106− ghc-options: -Wall
107− main-is: Property.hs
108− build-depends:
109− base >= 4.10.0.0
110− , bytestring >= 0.10.8.2
111− , hedgehog >= 1.0
112− , mtl >= 2.2.2
113− , scientific >= 0.3.5.3
114− , squeal-postgresql
115− , time >= 1.8.0.2
116−
117−test-suite spec
118− default-language: Haskell2010
119− type: exitcode-stdio-1.0
120− hs-source-dirs: test
121− ghc-options: -Wall
122− main-is: Spec.hs
123− build-depends:
124− base >= 4.10.0.0
125− , async >= 2.2.2
126− , bytestring >= 0.10.8.2
127− , generics-sop >= 0.3.1.0
128− , hspec >= 2.4.8
129− , mtl >= 2.2.2
130− , squeal-postgresql
131− , text >= 1.2.2.2
132− , vector >= 0.12.0.1
133
71
134−executable example
72+executable squeal-postgresql-example
135 default-language: Haskell2010
73 default-language: Haskell2010
136 hs-source-dirs: exe
74 hs-source-dirs: exe
137 ghc-options: -Wall
75 ghc-options: -Wall
@@ -144,4 +82,5 @@ executable example
144 , squeal-postgresql
82 , squeal-postgresql
145 , text >= 1.2.2.2
83 , text >= 1.2.2.2
146 , transformers >= 0.5.2.0
84 , transformers >= 0.5.2.0
85+ , transformers-base >= 0.4.4
147 , vector >= 0.12.0.1
86 , vector >= 0.12.0.1
squeal-postgresql/src/Squeal/PostgreSQL.hs+106−112
@@ -1,7 +1,7 @@
1{-|
1{-|
2Module: Squeal.PostgreSQL
2Module: Squeal.PostgreSQL
3−Description: Squeal export module
3+Description: Squeel export module
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
@@ -11,15 +11,17 @@ Let's see an example!
11First, we need some language extensions because Squeal uses modern GHC
11First, we need some language extensions because Squeal uses modern GHC
12features.
12features.
13
13
14−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
14+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
15−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
15+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators
16−
16+
17We'll need some imports.
17We'll need some imports.
18
18
19−>>> import Control.Monad.IO.Class (liftIO)
19+>>> import Control.Monad (void)
20+>>> import Control.Monad.Base (liftBase)
20>>> import Data.Int (Int32)
21>>> import Data.Int (Int32)
21>>> import Data.Text (Text)
22>>> import Data.Text (Text)
22>>> import Squeal.PostgreSQL
23>>> import Squeal.PostgreSQL
24+>>> import Squeal.PostgreSQL.Render
23
25
24We'll use generics to easily convert between Haskell and PostgreSQL values.
26We'll use generics to easily convert between Haskell and PostgreSQL values.
25
27
@@ -30,26 +32,26 @@ The first step is to define the schema of our database. This is where
30we use @DataKinds@ and @TypeOperators@.
32we use @DataKinds@ and @TypeOperators@.
31
33
32>>> :{
34>>> :{
33−type UsersColumns =
34− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
35− , "name" ::: 'NoDef :=> 'NotNull 'PGtext ]
36−type UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]
37−type EmailsColumns =
38− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
39− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
40− , "email" ::: 'NoDef :=> 'Null 'PGtext ]
41−type EmailsConstraints =
42− '[ "pk_emails" ::: 'PrimaryKey '["id"]
43− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"] ]
44type Schema =
35type Schema =
45− '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)
36+ '[ "users" ::: 'Table (
37+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
38+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
39+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
40+ ])
46− , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]
41+ , "emails" ::: 'Table (
47−type Schemas = Public Schema
42+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
43+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
44+ ] :=>
45+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
46+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
47+ , "email" ::: 'NoDef :=> 'Null 'PGtext
48+ ])
49+ ]
48:}
50:}
49
51
50Notice the use of type operators.
52Notice the use of type operators.
51
53
52−`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemasType`, a `SchemumType`,
54+`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemumType`,
53a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's @::@
55a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's @::@
54operator.
56operator.
55
57
@@ -58,7 +60,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
58yielding a `ColumnType`. It is intended to connote Haskell's @=>@ operator
60yielding a `ColumnType`. It is intended to connote Haskell's @=>@ operator
59
61
60Next, we'll write `Definition`s to set up and tear down the schema. In
62Next, we'll write `Definition`s to set up and tear down the schema. In
61−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
63+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
62has two type parameters, corresponding to the schema
64has two type parameters, corresponding to the schema
63before being run and the schema after. We can compose definitions using `>>>`.
65before being run and the schema after. We can compose definitions using `>>>`.
64Here and in the rest of our commands we make use of overloaded
66Here and in the rest of our commands we make use of overloaded
@@ -66,19 +68,19 @@ labels to refer to named tables and columns in our schema.
66
68
67>>> :{
69>>> :{
68let
70let
69− setup :: Definition (Public '[]) Schemas
71+ setup :: Definition '[] Schema
70− setup =
72+ setup =
71 createTable #users
73 createTable #users
72− ( serial `as` #id :*
74+ ( serial `As` #id :*
73− (text & notNullable) `as` #name )
75+ (text & notNullable) `As` #name :* Nil )
74− ( primaryKey #id `as` #pk_users ) >>>
76+ ( primaryKey #id `As` #pk_users :* Nil ) >>>
75 createTable #emails
77 createTable #emails
76− ( serial `as` #id :*
78+ ( serial `As` #id :*
77− (int & notNullable) `as` #user_id :*
79+ (int & notNullable) `As` #user_id :*
78− (text & nullable) `as` #email )
80+ (text & nullable) `As` #email :* Nil )
79− ( primaryKey #id `as` #pk_emails :*
81+ ( primaryKey #id `As` #pk_emails :*
80 foreignKey #user_id #users #id
82 foreignKey #user_id #users #id
81− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
83+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
82:}
84:}
83
85
84We can easily see the generated SQL is unsurprising looking.
86We can easily see the generated SQL is unsurprising looking.
@@ -87,14 +89,14 @@ We can easily see the generated SQL is unsurprising looking.
87CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
89CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
88CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
90CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
89
91
90−Notice that @setup@ starts with an empty public schema @(Public '[])@ and produces @Schemas@.
92+Notice that @setup@ starts with an empty schema @'[]@ and produces @Schema@.
91In our `createTable` commands we included `TableConstraint`s to define
93In our `createTable` commands we included `TableConstraint`s to define
92primary and foreign keys, making them somewhat complex. Our @teardown@
94primary and foreign keys, making them somewhat complex. Our @teardown@
93`Definition` is simpler.
95`Definition` is simpler.
94
96
95>>> :{
97>>> :{
96let
98let
97− teardown :: Definition Schemas (Public '[])
99+ teardown :: Definition Schema '[]
98 teardown = dropTable #emails >>> dropTable #users
100 teardown = dropTable #emails >>> dropTable #users
99:}
101:}
100
102
@@ -102,64 +104,76 @@ let
102DROP TABLE "emails";
104DROP TABLE "emails";
103DROP TABLE "users";
105DROP TABLE "users";
104
106
105−We'll need a Haskell type for @User@s. We give the type `Generics.SOP.Generic` and
106−`Generics.SOP.HasDatatypeInfo` instances so that we can encode and decode @User@s.
107−
108−>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
109−>>> instance SOP.Generic User
110−>>> instance SOP.HasDatatypeInfo User
111−
112−Next, we'll write `Manipulation_`s to insert @User@s into our two tables.
107+Next, we'll write `Manipulation`s to insert data into our two tables.
113−A `Manipulation_` like `insertInto`, `update` or `deleteFrom`
108+A `Manipulation` like `insertRow`, `update` or `deleteFrom`
114−has three type parameters, the schemas it refers to, input parameters
109+has three type parameters, the schema it refers to, a list of parameters
115−and an output row. When
110+it can take as input, and a list of columns it produces as output. When
116we insert into the users table, we will need a parameter for the @name@
111we insert into the users table, we will need a parameter for the @name@
117field but not for the @id@ field. Since it's serial, we can use a default
112field but not for the @id@ field. Since it's serial, we can use a default
118value. However, since the emails table refers to the users table, we will
113value. However, since the emails table refers to the users table, we will
119need to retrieve the user id that the insert generates and insert it into
114need to retrieve the user id that the insert generates and insert it into
120−the emails table. We can do this in a single `Manipulation_` by using a
115+the emails table. Take a careful look at the type and definition of both
121−`with` statement.
116+of our inserts.
117+
118+>>> :{
119+let
120+ insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]
121+ insertUser = insertRow #users
122+ (Default `As` #id :* Set (param @1) `As` #name :* Nil)
123+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))
124+:}
122
125
123>>> :{
126>>> :{
124let
127let
125− insertUser :: Manipulation_ Schemas User ()
128+ insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
126− insertUser = with (u `as` #u) e
129+ insertEmail = insertRow #emails
127− where
130+ ( Default `As` #id :*
128− u = insertInto #users
131+ Set (param @1) `As` #user_id :*
129− (Values_ (Default `as` #id :* Set (param @1) `as` #name))
132+ Set (param @2) `As` #email :* Nil )
130− OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))
133+ OnConflictDoNothing (Returning Nil)
131− e = insertInto_ #emails $ Select
132− (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)
133− (from (common #u))
134:}
134:}
135
135
136>>> printSQL insertUser
136>>> printSQL insertUser
137−WITH "u" AS (INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) RETURNING "id" AS "id", ($2 :: text) AS "email") INSERT INTO "emails" ("user_id", "email") SELECT "u"."id", "u"."email" FROM "u" AS "u"
137+INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) ON CONFLICT DO NOTHING RETURNING "id" AS "fromOnly"
138+>>> printSQL insertEmail
139+INSERT INTO "emails" ("id", "user_id", "email") VALUES (DEFAULT, ($1 :: int4), ($2 :: text)) ON CONFLICT DO NOTHING
138
140
139−Next we write a `Query_` to retrieve users from the database. We're not
141+Next we write a `Query` to retrieve users from the database. We're not
140interested in the ids here, just the usernames and email addresses. We
142interested in the ids here, just the usernames and email addresses. We
141−need to use an `innerJoin` to get the right result. A `Query_` is like a
143+need to use an inner join to get the right result. A `Query` is like a
142−`Manipulation_` with the same kind of type parameters.
144+`Manipulation` with the same kind of type parameters.
143
145
144>>> :{
146>>> :{
145let
147let
146− getUsers :: Query_ Schemas () User
148+ getUsers :: Query Schema '[]
149+ '[ "userName" ::: 'NotNull 'PGtext
150+ , "userEmail" ::: 'Null 'PGtext ]
147− getUsers = select_
151+ getUsers = select
148− (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)
152+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* Nil)
149− ( from (table (#users `as` #u)
153+ ( from (table (#users `As` #u)
150− & innerJoin (table (#emails `as` #e))
154+ & innerJoin (table (#emails `As` #e))
151 (#u ! #id .== #e ! #user_id)) )
155 (#u ! #id .== #e ! #user_id)) )
152:}
156:}
153
157
154>>> printSQL getUsers
158>>> printSQL getUsers
155SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
159SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
156
160
161+Now that we've defined the SQL side of things, we'll need a Haskell type
162+for users. We give the type `Generics.SOP.Generic` and
163+`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows
164+we receive when we run @getUsers@. Notice that the record fields of the
165+@User@ type match the column names of @getUsers@.
166+
167+>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
168+>>> instance SOP.Generic User
169+>>> instance SOP.HasDatatypeInfo User
170+
157−Let's create some users to add to the database.
171+Let's also create some users to add to the database.
158
172
159>>> :{
173>>> :{
160let
174let
161 users :: [User]
175 users :: [User]
162− users =
176+ users =
163 [ User "Alice" (Just "alice@gmail.com")
177 [ User "Alice" (Just "alice@gmail.com")
164 , User "Bob" Nothing
178 , User "Bob" Nothing
165 , User "Carole" (Just "carole@hotmail.com")
179 , User "Carole" (Just "carole@hotmail.com")
@@ -176,58 +190,38 @@ transformer and when the schema doesn't change we can use `Monad` and
176
190
177>>> :{
191>>> :{
178let
192let
179− session :: PQ Schemas Schemas IO ()
193+ session :: PQ Schema Schema IO ()
180 session = do
194 session = do
181− _ <- traversePrepared_ insertUser users
195+ idResults <- traversePrepared insertUser (Only . userName <$> users)
196+ ids <- traverse (fmap fromOnly . getRow 0) idResults
197+ traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
182 usersResult <- runQuery getUsers
198 usersResult <- runQuery getUsers
183 usersRows <- getRows usersResult
199 usersRows <- getRows usersResult
184− liftIO $ print (usersRows :: [User])
200+ liftBase $ print (usersRows :: [User])
185in
201in
186− withConnection "host=localhost port=5432 dbname=exampledb" $
202+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
187 define setup
203 define setup
188 & pqThen session
204 & pqThen session
189 & pqThen (define teardown)
205 & pqThen (define teardown)
190:}
206:}
191[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
207[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
192-}
208-}
193−module Squeal.PostgreSQL (module X, RenderSQL(..), printSQL) where
209+module Squeal.PostgreSQL
194−
210+ ( module Squeal.PostgreSQL.Binary
211+ , module Squeal.PostgreSQL.Definition
212+ , module Squeal.PostgreSQL.Expression
213+ , module Squeal.PostgreSQL.Manipulation
214+ , module Squeal.PostgreSQL.PQ
215+ , module Squeal.PostgreSQL.Query
216+ , module Squeal.PostgreSQL.Schema
217+ , module Squeal.PostgreSQL.Transaction
218+ ) where
219+
195−import Squeal.PostgreSQL.Alias as X
220+import Squeal.PostgreSQL.Binary
196−import Squeal.PostgreSQL.Binary as X
197−import Squeal.PostgreSQL.Definition as X
221+import Squeal.PostgreSQL.Definition
198−import Squeal.PostgreSQL.Definition.Function as X
199−import Squeal.PostgreSQL.Definition.Index as X
200−import Squeal.PostgreSQL.Definition.Schema as X
201−import Squeal.PostgreSQL.Definition.Table as X
202−import Squeal.PostgreSQL.Definition.Table.Constraint as X
203−import Squeal.PostgreSQL.Definition.Type as X
204−import Squeal.PostgreSQL.Definition.View as X
205−import Squeal.PostgreSQL.Expression as X
222+import Squeal.PostgreSQL.Expression
206−import Squeal.PostgreSQL.Expression.Aggregate as X
207−import Squeal.PostgreSQL.Expression.Collection as X
208−import Squeal.PostgreSQL.Expression.Comparison as X
209−import Squeal.PostgreSQL.Expression.Json as X
210−import Squeal.PostgreSQL.Expression.Literal as X
211−import Squeal.PostgreSQL.Expression.Logic as X
212−import Squeal.PostgreSQL.Expression.Math as X
213−import Squeal.PostgreSQL.Expression.Null as X
214−import Squeal.PostgreSQL.Expression.Parameter as X
215−import Squeal.PostgreSQL.Expression.Range as X
216−import Squeal.PostgreSQL.Expression.Set as X
217−import Squeal.PostgreSQL.Expression.Sort as X
218−import Squeal.PostgreSQL.Expression.Subquery as X
219−import Squeal.PostgreSQL.Expression.Text as X
220−import Squeal.PostgreSQL.Expression.TextSearch as X
221−import Squeal.PostgreSQL.Expression.Time as X
222−import Squeal.PostgreSQL.Expression.Type as X
223−import Squeal.PostgreSQL.Expression.Window as X
224−import Squeal.PostgreSQL.List as X
225−import Squeal.PostgreSQL.Manipulation as X
223+import Squeal.PostgreSQL.Manipulation
226−import Squeal.PostgreSQL.Migration as X
227−import Squeal.PostgreSQL.PG as X
228−import Squeal.PostgreSQL.Pool as X
229−import Squeal.PostgreSQL.PQ as X
224+import Squeal.PostgreSQL.PQ
230−import Squeal.PostgreSQL.Query as X
225+import Squeal.PostgreSQL.Query
231−import Squeal.PostgreSQL.Render (RenderSQL(..), printSQL)
232−import Squeal.PostgreSQL.Schema as X
226+import Squeal.PostgreSQL.Schema
233−import Squeal.PostgreSQL.Transaction as X
227+import Squeal.PostgreSQL.Transaction
squeal-postgresql/src/Squeal/PostgreSQL/Alias.hsdeleted−249
@@ -1,249 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Alias
3−Description: Aliases
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−This module embeds Postgres's alias system in Haskell in
9−a typesafe fashion. Thanks to GHC's @OverloadedLabels@ extension,
10−Squeal can reference aliases by prepending with a @#@.
11−-}
12−
13−{-# LANGUAGE
14− AllowAmbiguousTypes
15− , ConstraintKinds
16− , DeriveAnyClass
17− , DeriveGeneric
18− , FlexibleContexts
19− , FlexibleInstances
20− , FunctionalDependencies
21− , GADTs
22− , LambdaCase
23− , OverloadedStrings
24− , QuantifiedConstraints
25− , RankNTypes
26− , ScopedTypeVariables
27− , StandaloneDeriving
28− , TypeApplications
29− , TypeFamilyDependencies
30− , TypeInType
31− , TypeOperators
32− , UndecidableInstances
33− , UndecidableSuperClasses
34−#-}
35−
36−module Squeal.PostgreSQL.Alias
37− ( (:::)
38− , Alias (..)
39− , IsLabel (..)
40− , Aliased (As)
41− , Aliasable (as)
42− , renderAliased
43− , Has
44− , HasUnique
45− , HasAll
46− , HasIn
47− , QualifiedAlias (..)
48− , IsQualified (..)
49− -- * Grouping
50− , Grouping (..)
51− , GroupedBy
52− ) where
53−
54−import Control.DeepSeq
55−import Data.ByteString (ByteString)
56−import Data.String (fromString)
57−import GHC.OverloadedLabels
58−import GHC.TypeLits
59−
60−import qualified Generics.SOP as SOP
61−import qualified GHC.Generics as GHC
62−
63−import Squeal.PostgreSQL.List
64−import Squeal.PostgreSQL.Render
65−
66−-- $setup
67−-- >>> import Squeal.PostgreSQL
68−
69−-- | The alias operator `:::` is like a promoted version of `As`,
70−-- a type level pair between an alias and some type.
71−type (:::) (alias :: Symbol) ty = '(alias,ty)
72−infixr 6 :::
73−
74−
75−-- | `Grouping` is an auxiliary namespace, created by
76−-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used
77−-- for typesafe aggregation
78−data Grouping
79− = Ungrouped -- ^ no aggregation permitted
80− | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped
81−
82−{- | A `GroupedBy` constraint indicates that a table qualified column is
83−a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,
84−may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.
85−-}
86−class (KnownSymbol table, KnownSymbol column)
87− => GroupedBy table column bys where
88−instance {-# OVERLAPPING #-} (KnownSymbol table, KnownSymbol column)
89− => GroupedBy table column ('(table,column) ': bys)
90−instance {-# OVERLAPPABLE #-}
91− ( KnownSymbol table
92− , KnownSymbol column
93− , GroupedBy table column bys
94− ) => GroupedBy table column (tabcol ': bys)
95−
96−-- | `Alias`es are proxies for a type level string or `Symbol`
97−-- and have an `IsLabel` instance so that with @-XOverloadedLabels@
98−--
99−-- >>> :set -XOverloadedLabels
100−-- >>> #foobar :: Alias "foobar"
101−-- Alias
102−data Alias (alias :: Symbol) = Alias
103− deriving (Eq,GHC.Generic,Ord,Show,NFData)
104−instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where
105− fromLabel = Alias
106−instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where
107− fromLabel = fromLabel SOP.:* Nil
108−-- | >>> printSQL (#jimbob :: Alias "jimbob")
109−-- "jimbob"
110−instance KnownSymbol alias => RenderSQL (Alias alias) where
111− renderSQL = doubleQuoted . fromString . symbolVal
112−
113−-- >>> printSQL (#jimbob :* #kandi :: NP Alias '["jimbob", "kandi"])
114−-- "jimbob", "kandi"
115−instance SOP.All KnownSymbol aliases => RenderSQL (NP Alias aliases) where
116− renderSQL
117− = commaSeparated
118− . SOP.hcollapse
119− . SOP.hcmap (SOP.Proxy @KnownSymbol) (SOP.K . renderSQL)
120−
121−-- | The `As` operator is used to name an expression. `As` is like a demoted
122−-- version of `:::`.
123−--
124−-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)
125−-- As (Just "hello") Alias
126−data Aliased expression aliased where
127− As
128− :: KnownSymbol alias
129− => expression ty
130− -> Alias alias
131− -> Aliased expression (alias ::: ty)
132−deriving instance Show (expression ty)
133− => Show (Aliased expression (alias ::: ty))
134−deriving instance Eq (expression ty)
135− => Eq (Aliased expression (alias ::: ty))
136−deriving instance Ord (expression ty)
137− => Ord (Aliased expression (alias ::: ty))
138−instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)
139− => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where
140− fromLabel = fromLabel @alias2 `As` fromLabel @alias1
141−
142−-- | The `Aliasable` class provides a way to scrap your `Nil`s
143−-- in an `NP` list of `Aliased` expressions.
144−class KnownSymbol alias => Aliasable alias expression aliased
145− | aliased -> expression
146− , aliased -> alias
147− where as :: expression -> Alias alias -> aliased
148−instance (KnownSymbol alias, aliased ~ (alias ::: ty)) => Aliasable alias
149− (expression ty)
150− (Aliased expression aliased)
151− where
152− as = As
153−instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias
154− (expression ty)
155− (NP (Aliased expression) tys)
156− where
157− expression `as` alias = expression `As` alias SOP.:* Nil
158−
159−-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")
160−-- >>> renderAliased renderMaybe (Just (3::Int) `As` #an_int)
161−-- "Just AS \"an_int\""
162−renderAliased
163− :: (forall ty. expression ty -> ByteString)
164− -> Aliased expression aliased
165− -> ByteString
166−renderAliased render (expression `As` alias) =
167− render expression <> " AS " <> renderSQL alias
168−
169−-- | @HasUnique alias fields field@ is a constraint that proves that
170−-- @fields@ is a singleton of @alias ::: field@.
171−type HasUnique alias fields field = fields ~ '[alias ::: field]
172−
173−-- | @Has alias fields field@ is a constraint that proves that
174−-- @fields@ has a field of @alias ::: field@, inferring @field@
175−-- from @alias@ and @fields@.
176−class KnownSymbol alias =>
177− Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)
178− | alias fields -> field where
179−instance {-# OVERLAPPING #-} KnownSymbol alias
180− => Has alias (alias ::: field ': fields) field
181−instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)
182− => Has alias (field' ': fields) field
183−
184−{-| @HasIn fields (alias ::: field)@ is a constraint that proves that
185−@fields@ has a field of @alias ::: field@. It is used in @UPDATE@s to
186−choose which subfields to update.
187−-}
188−class HasIn fields field where
189−instance (Has alias fields field) => HasIn fields (alias ::: field) where
190−
191−-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer
192−-- a list of @subfields@.
193−class
194− ( SOP.All KnownSymbol aliases
195− ) => HasAll
196− (aliases :: [Symbol])
197− (fields :: [(Symbol,kind)])
198− (subfields :: [(Symbol,kind)])
199− | aliases fields -> subfields where
200−instance {-# OVERLAPPING #-} HasAll '[] fields '[]
201−instance {-# OVERLAPPABLE #-}
202− (Has alias fields field, HasAll aliases fields subfields)
203− => HasAll (alias ': aliases) fields (alias ::: field ': subfields)
204−
205−-- | Analagous to `IsLabel`, the constraint
206−-- `IsQualified` defines `!` for a column alias qualified
207−-- by a table alias.
208−class IsQualified table column expression where
209− (!) :: Alias table -> Alias column -> expression
210− infixl 9 !
211−instance IsQualified table column (Alias table, Alias column) where (!) = (,)
212−
213−{-| `QualifiedAlias`es enables multi-schema support by allowing a reference
214−to a `Squeal.PostgreSQL.Schema.Table`, `Squeal.PostgreSQL.Schema.Typedef`
215−or `Squeal.PostgreSQL.Schema.View` to be qualified by their schemas. By default,
216−a qualifier of @public@ is provided.
217−
218−>>> :{
219−let
220− alias1 :: QualifiedAlias "sch" "tab"
221− alias1 = #sch ! #tab
222− alias2 :: QualifiedAlias "public" "vw"
223− alias2 = #vw
224−in printSQL alias1 >> printSQL alias2
225−:}
226−"sch"."tab"
227−"vw"
228−-}
229−data QualifiedAlias (qualifier :: Symbol) (alias :: Symbol) = QualifiedAlias
230− deriving (Eq,GHC.Generic,Ord,Show,NFData)
231−instance (q ~ q', a ~ a') => IsQualified q a (QualifiedAlias q' a') where
232− _!_ = QualifiedAlias
233−instance (q' ~ "public", a ~ a') => IsLabel a (QualifiedAlias q' a') where
234− fromLabel = QualifiedAlias
235−instance (q0 ~ q1, a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>
236− IsQualified q0 a0 (Aliased (QualifiedAlias q1) (a1 ::: a2)) where
237− _!_ = QualifiedAlias `As` Alias
238−instance (q ~ "public", a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>
239− IsLabel a0 (Aliased (QualifiedAlias q) (a1 ::: a2)) where
240− fromLabel = QualifiedAlias `As` Alias
241−
242−instance (KnownSymbol q, KnownSymbol a)
243− => RenderSQL (QualifiedAlias q a) where
244− renderSQL _ =
245− let
246− qualifier = renderSQL (Alias @q)
247− alias = renderSQL (Alias @a)
248− in
249− if qualifier == "\"public\"" then alias else qualifier <> "." <> alias
squeal-postgresql/src/Squeal/PostgreSQL/Binary.hs+221−534
@@ -7,157 +7,103 @@ Stability: experimental
7
7
8This module provides binary encoding and decoding between Haskell and PostgreSQL types.
8This module provides binary encoding and decoding between Haskell and PostgreSQL types.
9
9
10−Instances are governed by the `SOP.Generic` and `SOP.HasDatatypeInfo` typeclasses, so you absolutely
10+Instances are governed by the `Generic` and `HasDatatypeInfo` typeclasses, so you absolutely
11do not need to define your own instances to decode retrieved rows into Haskell values or
11do not need to define your own instances to decode retrieved rows into Haskell values or
12to encode Haskell values into statement parameters.
12to encode Haskell values into statement parameters.
13
13
14−Let's see some examples. We'll need some imports
15−
16>>> import Data.Int (Int16)
14>>> import Data.Int (Int16)
17>>> import Data.Text (Text)
15>>> import Data.Text (Text)
18−>>> import Control.Monad (void)
19−>>> import Control.Monad.IO.Class (liftIO)
20−>>> import Squeal.PostgreSQL
21−
22−Define a Haskell datatype @Row@ that will serve as both the input and output of a simple
23−round trip query.
24
16
25−>>> data Row = Row { col1 :: Int16, col2 :: Text, col3 :: Maybe Bool } deriving (Eq, GHC.Generic)
17+>>> data Row = Row { col1 :: Int16, col2 :: Text } deriving (Eq, GHC.Generic)
26>>> instance Generic Row
18>>> instance Generic Row
27>>> instance HasDatatypeInfo Row
19>>> instance HasDatatypeInfo Row
28−>>> :{
29−let
30− roundTrip :: Query_ (Public '[]) Row Row
31− roundTrip = values_ $
32− parameter @1 int2 `as` #col1 :*
33− parameter @2 text `as` #col2 :*
34− parameter @3 bool `as` #col3
35−:}
36
20
37−So long as we can encode the parameters and then decode the result of the query,
21+>>> import Control.Monad (void)
38−the input and output should be equal.
22+>>> import Control.Monad.Base (liftBase)
23+>>> import Squeal.PostgreSQL
39
24
40−>>> let input = Row 2 "hi" (Just True)
41>>> :{
25>>> :{
42−withConnection "host=localhost port=5432 dbname=exampledb" $ do
26+let
43− result <- runQueryParams roundTrip input
27+ query :: Query '[]
44− Just output <- firstRow result
28+ '[ 'NotNull 'PGint2, 'NotNull 'PGtext]
45− liftIO . print $ input == output
29+ '["col1" ::: 'NotNull 'PGint2, "col2" ::: 'NotNull 'PGtext]
30+ query = values_ (param @1 `As` #col1 :* param @2 `As` #col2 :* Nil)
46:}
31:}
47−True
48−
49−In addition to being able to encode and decode basic Haskell types
50−like `Int16` and `Data.Text.Text`, Squeal permits you to encode and decode Haskell types to
51−Postgres array, enumerated and composite types and json. Let's see another example,
52−this time using the `Vector` type which corresponds to variable length arrays
53−and homogeneous tuples which correspond to fixed length arrays. We can even
54−create multi-dimensional fixed length arrays.
55−
56−>>> :{
57−data Row = Row
58− { col1 :: VarArray (Vector Int16)
59− , col2 :: FixArray (Maybe Int16,Maybe Int16)
60− , col3 :: FixArray ((Int16,Int16),(Int16,Int16),(Int16,Int16))
61− } deriving (Eq, GHC.Generic)
62−:}
63−
64−>>> instance Generic Row
65−>>> instance HasDatatypeInfo Row
66−
67−Once again, we define a simple round trip query.
68
32
69>>> :{
33>>> :{
70let
34let
71− roundTrip :: Query_ (Public '[]) Row Row
35+ roundtrip :: IO ()
72− roundTrip = values_ $
36+ roundtrip = void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
73− parameter @1 (int2 & vararray) `as` #col1 :*
37+ result <- runQueryParams query (2 :: Int16, "hi" :: Text)
74− parameter @2 (int2 & fixarray @'[2]) `as` #col2 :*
38+ Just row <- firstRow result
75− parameter @3 (int2 & fixarray @'[3,2]) `as` #col3
39+ liftBase . print $ row == Row 2 "hi"
76:}
40:}
77
41
78−>>> :set -XOverloadedLists
42+>>> roundtrip
79−>>> let input = Row (VarArray [1,2]) (FixArray (Just 1,Nothing)) (FixArray ((1,2),(3,4),(5,6)))
80−>>> :{
81−withConnection "host=localhost port=5432 dbname=exampledb" $ do
82− result <- runQueryParams roundTrip input
83− Just output <- firstRow result
84− liftIO . print $ input == output
85−:}
86True
43True
87
44
45+In addition to being able to encode and decode basic Haskell types like `Int16` and `Text`,
46+Squeal permits you to encode and decode Haskell types which are equivalent to
47+Postgres enumerated and composite types.
48+
88Enumerated (enum) types are data types that comprise a static, ordered set of values.
49Enumerated (enum) types are data types that comprise a static, ordered set of values.
89They are equivalent to Haskell algebraic data types whose constructors are nullary.
50They are equivalent to Haskell algebraic data types whose constructors are nullary.
90An example of an enum type might be the days of the week,
51An example of an enum type might be the days of the week,
91or a set of status values for a piece of data.
52or a set of status values for a piece of data.
92
53
93−>>> data Schwarma = Beef | Lamb | Chicken deriving (Eq, Show, GHC.Generic)
54+>>> data Schwarma = Beef | Lamb | Chicken deriving (Show, GHC.Generic)
94>>> instance Generic Schwarma
55>>> instance Generic Schwarma
95>>> instance HasDatatypeInfo Schwarma
56>>> instance HasDatatypeInfo Schwarma
96
57
97A composite type represents the structure of a row or record;
58A composite type represents the structure of a row or record;
98−it is essentially just a list of field names and their data types.
59+it is essentially just a list of field names and their data types. They are almost
60+equivalent to Haskell record types. However, because of the potential presence of @NULL@
61+all the record fields must be `Maybe`s of basic types.
99
62
100−>>> data Person = Person {name :: Text, age :: Int32} deriving (Eq, Show, GHC.Generic)
63+>>> data Person = Person {name :: Maybe Text, age :: Maybe Int32} deriving (Show, GHC.Generic)
101>>> instance Generic Person
64>>> instance Generic Person
102>>> instance HasDatatypeInfo Person
65>>> instance HasDatatypeInfo Person
103−>>> instance Aeson.FromJSON Person
104−>>> instance Aeson.ToJSON Person
105
66
106We can create the equivalent Postgres types directly from their Haskell types.
67We can create the equivalent Postgres types directly from their Haskell types.
107
68
108>>> :{
69>>> :{
109type Schema =
70type Schema =
110− '[ "schwarma" ::: 'Typedef (PG (Enumerated Schwarma))
71+ '[ "schwarma" ::: 'Typedef (EnumFrom Schwarma)
111− , "person" ::: 'Typedef (PG (Composite Person))
72+ , "person" ::: 'Typedef (CompositeFrom Person)
112 ]
73 ]
113:}
74:}
114
75
115>>> :{
76>>> :{
116let
77let
117− setup :: Definition (Public '[]) (Public Schema)
78+ setup :: Definition '[] Schema
118 setup =
79 setup =
119 createTypeEnumFrom @Schwarma #schwarma >>>
80 createTypeEnumFrom @Schwarma #schwarma >>>
120 createTypeCompositeFrom @Person #person
81 createTypeCompositeFrom @Person #person
121:}
82:}
122
83
123−Let's demonstrate how to associate our Haskell types @Schwarma@ and @Person@
84+Then we can perform roundtrip queries;
124−with enumerated, composite or json types in Postgres. First create a Haskell
125−@Row@ type using the `Enumerated`, `Composite` and `Json` newtypes as fields.
126
85
127−>>> :{
128−data Row = Row
129− { schwarma :: Enumerated Schwarma
130− , person1 :: Composite Person
131− , person2 :: Json Person
132− } deriving (Eq, GHC.Generic)
133−:}
134−
135−>>> instance Generic Row
136−>>> instance HasDatatypeInfo Row
137>>> :{
86>>> :{
138let
87let
139− input = Row
88+ querySchwarma :: Query Schema
140− (Enumerated Chicken)
89+ '[ 'NotNull (EnumFrom Schwarma)]
141− (Composite (Person "Faisal" 24))
90+ '["fromOnly" ::: 'NotNull (EnumFrom Schwarma)]
142− (Json (Person "Ahmad" 48))
91+ querySchwarma = values_ (parameter @1 #schwarma `As` #fromOnly :* Nil)
143:}
92:}
144
93
145−Once again, define a round trip query.
146−
147>>> :{
94>>> :{
148let
95let
149− roundTrip :: Query_ (Public Schema) Row Row
96+ queryPerson :: Query Schema
150− roundTrip = values_ $
97+ '[ 'NotNull (CompositeFrom Person)]
151− parameter @1 (typedef #schwarma) `as` #schwarma :*
98+ '["fromOnly" ::: 'NotNull (CompositeFrom Person)]
152− parameter @2 (typedef #person) `as` #person1 :*
99+ queryPerson = values_ (parameter @1 #person `As` #fromOnly :* Nil)
153− parameter @3 json `as` #person2
154:}
100:}
155
101
156−Finally, we can drop our type definitions.
102+And finally drop the types.
157
103
158>>> :{
104>>> :{
159let
105let
160− teardown :: Definition (Public Schema) (Public '[])
106+ teardown :: Definition Schema '[]
161 teardown = dropType #schwarma >>> dropType #person
107 teardown = dropType #schwarma >>> dropType #person
162:}
108:}
163
109
@@ -166,16 +112,20 @@ Now let's run it.
166>>> :{
112>>> :{
167let
113let
168 session = do
114 session = do
169− result <- runQueryParams roundTrip input
115+ result1 <- runQueryParams querySchwarma (Only Chicken)
170− Just output <- firstRow result
116+ Just (Only schwarma) <- firstRow result1
171− liftIO . print $ input == output
117+ liftBase $ print (schwarma :: Schwarma)
118+ result2 <- runQueryParams queryPerson (Only (Person (Just "Faisal") (Just 24)))
119+ Just (Only person) <- firstRow result2
120+ liftBase $ print (person :: Person)
172in
121in
173− withConnection "host=localhost port=5432 dbname=exampledb" $
122+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
174 define setup
123 define setup
175 & pqThen session
124 & pqThen session
176 & pqThen (define teardown)
125 & pqThen (define teardown)
177:}
126:}
178−True
127+Chicken
128+Person {name = Just "Faisal", age = Just 24}
179-}
129-}
180
130
181{-# LANGUAGE
131{-# LANGUAGE
@@ -184,76 +134,55 @@ True
184 , DeriveFunctor
134 , DeriveFunctor
185 , DeriveGeneric
135 , DeriveGeneric
186 , DeriveTraversable
136 , DeriveTraversable
187− , DefaultSignatures
188 , FlexibleContexts
137 , FlexibleContexts
189 , FlexibleInstances
138 , FlexibleInstances
190− , FunctionalDependencies
191 , GADTs
139 , GADTs
192 , LambdaCase
140 , LambdaCase
193− , OverloadedStrings
194 , MultiParamTypeClasses
141 , MultiParamTypeClasses
195 , ScopedTypeVariables
142 , ScopedTypeVariables
196 , TypeApplications
143 , TypeApplications
197− , TypeFamilies
198 , TypeInType
144 , TypeInType
199 , TypeOperators
145 , TypeOperators
200 , UndecidableInstances
146 , UndecidableInstances
201− , UndecidableSuperClasses
202#-}
147#-}
203
148
204module Squeal.PostgreSQL.Binary
149module Squeal.PostgreSQL.Binary
205 ( -- * Encoding
150 ( -- * Encoding
206 ToParam (..)
151 ToParam (..)
152+ , ToColumnParam (..)
207 , ToParams (..)
153 , ToParams (..)
208− , ToNullityParam (..)
209− , ToField (..)
210− , ToFixArray (..)
211 -- * Decoding
154 -- * Decoding
212 , FromValue (..)
155 , FromValue (..)
156+ , FromColumnValue (..)
213 , FromRow (..)
157 , FromRow (..)
214− , FromField (..)
215− , FromFixArray (..)
216 -- * Only
158 -- * Only
217 , Only (..)
159 , Only (..)
218− -- * Oid
219− , OidOf (..)
220− , OidOfParam (..)
221− , OidOfField (..)
222 ) where
160 ) where
223
161
224import BinaryParser
162import BinaryParser
225−import ByteString.StrictBuilder (builderLength, int32BE, int64BE, word32BE)
163+import ByteString.StrictBuilder
226−import Control.Arrow (left)
164+import Data.Aeson hiding (Null)
227−import Control.Monad
228import Data.Int
165import Data.Int
229import Data.Kind
166import Data.Kind
167+import Data.Monoid hiding (All)
230import Data.Scientific
168import Data.Scientific
231import Data.Time
169import Data.Time
232import Data.UUID.Types
170import Data.UUID.Types
233import Data.Vector (Vector)
171import Data.Vector (Vector)
234import Data.Word
172import Data.Word
235−import Foreign.C.Types (CUInt(CUInt))
236import Generics.SOP
173import Generics.SOP
237−import Generics.SOP.Record
238import GHC.TypeLits
174import GHC.TypeLits
239import Network.IP.Addr
175import Network.IP.Addr
240
176
241−import qualified Data.Aeson as Aeson
177+import qualified Data.ByteString.Lazy as Lazy
242−import qualified Data.ByteString.Lazy as Lazy (ByteString)
243−import qualified Data.ByteString.Lazy as Lazy.ByteString
178+import qualified Data.ByteString as Strict hiding (pack, unpack)
244−import qualified Data.ByteString as Strict (ByteString)
245−import qualified Data.Text.Lazy as Lazy (Text)
179+import qualified Data.Text.Lazy as Lazy
246−import qualified Data.Text as Strict (Text)
247−import qualified Data.Text as Strict.Text
180+import qualified Data.Text as Strict
248import qualified Data.Vector as Vector
181import qualified Data.Vector as Vector
249−import qualified Database.PostgreSQL.LibPQ as LibPQ
250import qualified GHC.Generics as GHC
182import qualified GHC.Generics as GHC
251import qualified PostgreSQL.Binary.Decoding as Decoding
183import qualified PostgreSQL.Binary.Decoding as Decoding
252import qualified PostgreSQL.Binary.Encoding as Encoding
184import qualified PostgreSQL.Binary.Encoding as Encoding
253
185
254−import Squeal.PostgreSQL.Alias
255−import Squeal.PostgreSQL.List
256−import Squeal.PostgreSQL.PG
257import Squeal.PostgreSQL.Schema
186import Squeal.PostgreSQL.Schema
258
187
259-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into
188-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into
@@ -277,20 +206,19 @@ class ToParam (x :: Type) (pg :: PGType) where
277 toParam :: x -> K Encoding.Encoding pg
206 toParam :: x -> K Encoding.Encoding pg
278instance ToParam Bool 'PGbool where toParam = K . Encoding.bool
207instance ToParam Bool 'PGbool where toParam = K . Encoding.bool
279instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16
208instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16
209+instance ToParam Word16 'PGint2 where toParam = K . Encoding.int2_word16
280instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32
210instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32
211+instance ToParam Word32 'PGint4 where toParam = K . Encoding.int4_word32
281instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64
212instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64
282−instance ToParam Oid 'PGoid where toParam = K . Encoding.int4_word32 . getOid
213+instance ToParam Word64 'PGint8 where toParam = K . Encoding.int8_word64
283instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4
214instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4
284instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8
215instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8
285instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric
216instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric
286−instance ToParam Money 'PGmoney where toParam = K . Encoding.int8_int64 . cents
287instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid
217instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid
288instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet
218instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet
289instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8
219instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8
290instance ToParam Strict.Text 'PGtext where toParam = K . Encoding.text_strict
220instance ToParam Strict.Text 'PGtext where toParam = K . Encoding.text_strict
291instance ToParam Lazy.Text 'PGtext where toParam = K . Encoding.text_lazy
221instance ToParam Lazy.Text 'PGtext where toParam = K . Encoding.text_lazy
292−instance ToParam String 'PGtext where
293− toParam = K . Encoding.text_strict . Strict.Text.pack
294instance ToParam Strict.ByteString 'PGbytea where
222instance ToParam Strict.ByteString 'PGbytea where
295 toParam = K . Encoding.bytea_strict
223 toParam = K . Encoding.bytea_strict
296instance ToParam Lazy.ByteString 'PGbytea where
224instance ToParam Lazy.ByteString 'PGbytea where
@@ -304,40 +232,17 @@ instance ToParam LocalTime 'PGtimestamp where
304instance ToParam UTCTime 'PGtimestamptz where
232instance ToParam UTCTime 'PGtimestamptz where
305 toParam = K . Encoding.timestamptz_int
233 toParam = K . Encoding.timestamptz_int
306instance ToParam DiffTime 'PGinterval where toParam = K . Encoding.interval_int
234instance ToParam DiffTime 'PGinterval where toParam = K . Encoding.interval_int
307−instance ToParam Aeson.Value 'PGjson where toParam = K . Encoding.json_ast
235+instance ToParam Value 'PGjson where toParam = K . Encoding.json_ast
308−instance ToParam Aeson.Value 'PGjsonb where toParam = K . Encoding.jsonb_ast
236+instance ToParam Value 'PGjsonb where toParam = K . Encoding.jsonb_ast
309−instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where
237+instance (HasOid pg, ToParam x pg)
310− toParam = K . Encoding.json_bytes
311− . Lazy.ByteString.toStrict . Aeson.encode . getJson
312−instance Aeson.ToJSON x => ToParam (Jsonb x) 'PGjsonb where
313− toParam = K . Encoding.jsonb_bytes
314− . Lazy.ByteString.toStrict . Aeson.encode . getJsonb
315−instance (ToNullityParam x ty, ty ~ nullity pg, OidOf pg)
316− => ToParam (VarArray [x]) ('PGvararray ty) where
317− toParam = K
318− . Encoding.array_foldable
319− (getOid (oidOf @pg)) (unK . toNullityParam @x @ty)
320− . getVarArray
321−instance (ToParam x pg, OidOf pg)
322− => ToParam (VarArray (Vector x)) ('PGvararray ('NotNull pg)) where
323− toParam = K
324− . Encoding.array_vector (getOid (oidOf @pg)) (unK . toParam @x @pg)
325− . getVarArray
326−instance (ToParam x pg, OidOf pg)
327− => ToParam (VarArray (Vector (Maybe x))) ('PGvararray ('Null pg)) where
238+ => ToParam (Vector (Maybe x)) ('PGvararray pg) where
328− toParam = K
329− . Encoding.nullableArray_vector
239+ toParam = K . Encoding.nullableArray_vector
330− (getOid (oidOf @pg)) (unK . toParam @x @pg)
240+ (oid @pg) (unK . toParam @x @pg)
331− . getVarArray
332−instance (ToFixArray x dims ty, ty ~ nullity pg, OidOf pg)
333− => ToParam (FixArray x) ('PGfixarray dims ty) where
334− toParam = K . Encoding.array (getOid (oidOf @pg))
335− . unK . unK . toFixArray @x @dims @ty . getFixArray
336instance
241instance
337 ( IsEnumType x
242 ( IsEnumType x
338 , HasDatatypeInfo x
243 , HasDatatypeInfo x
339− , LabelsPG x ~ labels
244+ , LabelsFrom x ~ labels
340− ) => ToParam (Enumerated x) ('PGenum labels) where
245+ ) => ToParam x ('PGenum labels) where
341 toParam =
246 toParam =
342 let
247 let
343 gshowConstructor :: NP ConstructorInfo xss -> SOP I xss -> String
248 gshowConstructor :: NP ConstructorInfo xss -> SOP I xss -> String
@@ -348,23 +253,24 @@ instance
348 gshowConstructor constructors (SOP xs)
253 gshowConstructor constructors (SOP xs)
349 in
254 in
350 K . Encoding.text_strict
255 K . Encoding.text_strict
351− . Strict.Text.pack
256+ . Strict.pack
352 . gshowConstructor (constructorInfo (datatypeInfo (Proxy @x)))
257 . gshowConstructor (constructorInfo (datatypeInfo (Proxy @x)))
353 . from
258 . from
354− . getEnumerated
355instance
259instance
356 ( SListI fields
260 ( SListI fields
357− , IsRecord x xs
261+ , MapMaybes xs
262+ , IsProductType x (Maybes xs)
358− , AllZip ToField xs fields
263+ , AllZip ToAliasedParam xs fields
264+ , FieldNamesFrom x ~ AliasesOf fields
359− , All OidOfField fields
265+ , All HasAliasedOid fields
360− ) => ToParam (Composite x) ('PGcomposite fields) where
266+ ) => ToParam x ('PGcomposite fields) where
361 toParam =
267 toParam =
362 let
268 let
363
269
364− encoders = htrans (Proxy @ToField) toField
270+ encoders = htrans (Proxy @ToAliasedParam) toAliasedParam
365
271
366 composite
272 composite
367− :: All OidOfField row
273+ :: All HasAliasedOid row
368 => NP (K (Maybe Encoding.Encoding)) row
274 => NP (K (Maybe Encoding.Encoding)) row
369 -> K Encoding.Encoding ('PGcomposite row)
275 -> K Encoding.Encoding ('PGcomposite row)
370 composite fields = K $
276 composite fields = K $
@@ -381,179 +287,53 @@ instance
381 int32BE (fromIntegral (lengthSList (Proxy @xs))) <>
287 int32BE (fromIntegral (lengthSList (Proxy @xs))) <>
382 let
288 let
383 each
289 each
384− :: OidOfField field
290+ :: HasAliasedOid field
385 => K (Maybe Encoding.Encoding) field
291 => K (Maybe Encoding.Encoding) field
386 -> Encoding.Encoding
292 -> Encoding.Encoding
387 each (K field :: K (Maybe Encoding.Encoding) field) =
293 each (K field :: K (Maybe Encoding.Encoding) field) =
388− word32BE (getOid (oidOfField @field))
294+ word32BE (aliasedOid @field)
389 <> case field of
295 <> case field of
390 Nothing -> int64BE (-1)
296 Nothing -> int64BE (-1)
391 Just value ->
297 Just value ->
392 int32BE (fromIntegral (builderLength value))
298 int32BE (fromIntegral (builderLength value))
393 <> value
299 <> value
394 in
300 in
395− hcfoldMap (Proxy @OidOfField) each fields
301+ hcfoldMap (Proxy @HasAliasedOid) each fields
396
302
397 in
303 in
398− composite . encoders . toRecord . getComposite
304+ composite . encoders . unMaybes . unZ . unSOP . from
399−
305+
400−-- | The object identifier of a `PGType`.
306+class HasAliasedOid (field :: (Symbol, PGType)) where aliasedOid :: Word32
401−--
307+instance HasOid ty => HasAliasedOid (alias ::: ty) where aliasedOid = oid @ty
402−-- >>> :set -XTypeApplications
308+
403−-- >>> oidOf @'PGbool
309+class ToAliasedParam (x :: Type) (field :: (Symbol, PGType)) where
404−-- Oid 16
310+ toAliasedParam :: Maybe x -> K (Maybe Encoding.Encoding) field
405−class OidOf (ty :: PGType) where oidOf :: LibPQ.Oid
311+instance ToParam x ty => ToAliasedParam x (alias ::: ty) where
406−instance OidOf 'PGbool where oidOf = LibPQ.Oid 16
312+ toAliasedParam = \case
407−instance OidOf ('PGfixarray ns (null 'PGbool)) where oidOf = LibPQ.Oid 1000
313+ Nothing -> K Nothing
408−instance OidOf ('PGvararray (null 'PGbool)) where oidOf = LibPQ.Oid 1000
314+ Just x -> K . Just . unK $ toParam @x @ty x
409−instance OidOf 'PGint2 where oidOf = LibPQ.Oid 21
315+
410−instance OidOf ('PGfixarray ns (null 'PGint2)) where oidOf = LibPQ.Oid 1005
316+-- | A `ToColumnParam` constraint lifts the `ToParam` encoding
411−instance OidOf ('PGvararray (null 'PGint2)) where oidOf = LibPQ.Oid 1005
317+-- of a `Type` to a `NullityType`, encoding `Maybe`s to `Null`s. You should
412−instance OidOf 'PGint4 where oidOf = LibPQ.Oid 23
318+-- not define instances of `ToColumnParam`, just use the provided instances.
413−instance OidOf ('PGfixarray ns (null 'PGint4)) where oidOf = LibPQ.Oid 1007
319+class ToColumnParam (x :: Type) (ty :: NullityType) where
414−instance OidOf ('PGvararray (null 'PGint4)) where oidOf = LibPQ.Oid 1007
320+ -- | >>> toColumnParam @Int16 @('NotNull 'PGint2) 0
415−instance OidOf 'PGint8 where oidOf = LibPQ.Oid 20
321+ -- K (Just "\NUL\NUL")
416−instance OidOf ('PGfixarray ns (null 'PGint8)) where oidOf = LibPQ.Oid 1016
322+ --
417−instance OidOf ('PGvararray (null 'PGint8)) where oidOf = LibPQ.Oid 1016
323+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) (Just 0)
418−instance OidOf 'PGnumeric where oidOf = LibPQ.Oid 1700
324+ -- K (Just "\NUL\NUL")
419−instance OidOf ('PGfixarray ns (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231
325+ --
420−instance OidOf ('PGvararray (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231
326+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) Nothing
421−instance OidOf 'PGfloat4 where oidOf = LibPQ.Oid 700
327+ -- K Nothing
422−instance OidOf ('PGfixarray ns (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021
328+ toColumnParam :: x -> K (Maybe Strict.ByteString) ty
423−instance OidOf ('PGvararray (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021
329+instance ToParam x pg => ToColumnParam x ('NotNull pg) where
424−instance OidOf 'PGfloat8 where oidOf = LibPQ.Oid 701
330+ toColumnParam = K . Just . Encoding.encodingBytes . unK . toParam @x @pg
425−instance OidOf ('PGfixarray ns (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022
331+instance ToParam x pg => ToColumnParam (Maybe x) ('Null pg) where
426−instance OidOf ('PGvararray (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022
332+ toColumnParam = K . fmap (Encoding.encodingBytes . unK . toParam @x @pg)
427−instance OidOf 'PGmoney where oidOf = LibPQ.Oid 790
428−instance OidOf ('PGfixarray ns (null 'PGmoney)) where oidOf = LibPQ.Oid 791
429−instance OidOf ('PGvararray (null 'PGmoney)) where oidOf = LibPQ.Oid 791
430−instance OidOf ('PGchar n) where oidOf = LibPQ.Oid 18
431−instance OidOf ('PGfixarray ns (null ('PGchar n))) where oidOf = LibPQ.Oid 1002
432−instance OidOf ('PGvararray (null ('PGchar n))) where oidOf = LibPQ.Oid 1002
433−instance OidOf ('PGvarchar n) where oidOf = LibPQ.Oid 1043
434−instance OidOf ('PGfixarray ns (null ('PGvarchar n))) where oidOf = LibPQ.Oid 1015
435−instance OidOf ('PGvararray (null ('PGvarchar n))) where oidOf = LibPQ.Oid 1015
436−instance OidOf 'PGtext where oidOf = LibPQ.Oid 25
437−instance OidOf ('PGfixarray ns (null 'PGtext)) where oidOf = LibPQ.Oid 1009
438−instance OidOf ('PGvararray (null 'PGtext)) where oidOf = LibPQ.Oid 1009
439−instance OidOf 'PGbytea where oidOf = LibPQ.Oid 17
440−instance OidOf ('PGfixarray ns (null 'PGbytea)) where oidOf = LibPQ.Oid 1001
441−instance OidOf ('PGvararray (null 'PGbytea)) where oidOf = LibPQ.Oid 1001
442−instance OidOf 'PGtimestamp where oidOf = LibPQ.Oid 1114
443−instance OidOf ('PGfixarray ns (null 'PGtimestamp)) where oidOf = LibPQ.Oid 1115
444−instance OidOf ('PGvararray (null 'PGtimestamp)) where oidOf = LibPQ.Oid 1115
445−instance OidOf 'PGtimestamptz where oidOf = LibPQ.Oid 1184
446−instance OidOf ('PGfixarray ns (null 'PGtimestamptz)) where oidOf = LibPQ.Oid 1185
447−instance OidOf ('PGvararray (null 'PGtimestamptz)) where oidOf = LibPQ.Oid 1185
448−instance OidOf 'PGdate where oidOf = LibPQ.Oid 1082
449−instance OidOf ('PGfixarray ns (null 'PGdate)) where oidOf = LibPQ.Oid 1182
450−instance OidOf ('PGvararray (null 'PGdate)) where oidOf = LibPQ.Oid 1182
451−instance OidOf 'PGtime where oidOf = LibPQ.Oid 1083
452−instance OidOf ('PGfixarray ns (null 'PGtime)) where oidOf = LibPQ.Oid 1183
453−instance OidOf ('PGvararray (null 'PGtime)) where oidOf = LibPQ.Oid 1183
454−instance OidOf 'PGtimetz where oidOf = LibPQ.Oid 1266
455−instance OidOf ('PGfixarray ns (null 'PGtimetz)) where oidOf = LibPQ.Oid 1270
456−instance OidOf ('PGvararray (null 'PGtimetz)) where oidOf = LibPQ.Oid 1270
457−instance OidOf 'PGinterval where oidOf = LibPQ.Oid 1186
458−instance OidOf ('PGfixarray ns (null 'PGinterval)) where oidOf = LibPQ.Oid 1187
459−instance OidOf ('PGvararray (null 'PGinterval)) where oidOf = LibPQ.Oid 1187
460−instance OidOf 'PGuuid where oidOf = LibPQ.Oid 2950
461−instance OidOf ('PGfixarray ns (null 'PGuuid)) where oidOf = LibPQ.Oid 2951
462−instance OidOf ('PGvararray (null 'PGuuid)) where oidOf = LibPQ.Oid 2951
463−instance OidOf 'PGinet where oidOf = LibPQ.Oid 869
464−instance OidOf ('PGfixarray ns (null 'PGinet)) where oidOf = LibPQ.Oid 1041
465−instance OidOf ('PGvararray (null 'PGinet)) where oidOf = LibPQ.Oid 1041
466−instance OidOf 'PGjson where oidOf = LibPQ.Oid 114
467−instance OidOf ('PGfixarray ns (null 'PGjson)) where oidOf = LibPQ.Oid 199
468−instance OidOf ('PGvararray (null 'PGjson)) where oidOf = LibPQ.Oid 199
469−instance OidOf 'PGjsonb where oidOf = LibPQ.Oid 3802
470−instance OidOf ('PGfixarray ns (null 'PGjsonb)) where oidOf = LibPQ.Oid 3807
471−instance OidOf ('PGvararray (null 'PGjsonb)) where oidOf = LibPQ.Oid 3807
472−instance OidOf 'PGtsvector where oidOf = LibPQ.Oid 3614
473−instance OidOf ('PGfixarray ns (null 'PGtsvector)) where oidOf = LibPQ.Oid 3643
474−instance OidOf ('PGvararray (null 'PGtsvector)) where oidOf = LibPQ.Oid 3643
475−instance OidOf 'PGtsquery where oidOf = LibPQ.Oid 3615
476−instance OidOf ('PGfixarray ns (null 'PGtsquery)) where oidOf = LibPQ.Oid 3645
477−instance OidOf ('PGvararray (null 'PGtsquery)) where oidOf = LibPQ.Oid 3645
478−instance OidOf 'PGoid where oidOf = LibPQ.Oid 26
479−instance OidOf ('PGfixarray ns (null 'PGoid)) where oidOf = LibPQ.Oid 1028
480−instance OidOf ('PGvararray (null 'PGoid)) where oidOf = LibPQ.Oid 1028
481−instance OidOf ('PGrange 'PGint4) where oidOf = LibPQ.Oid 3904
482−instance OidOf ('PGfixarray ns (null ('PGrange 'PGint4))) where oidOf = LibPQ.Oid 3905
483−instance OidOf ('PGvararray (null ('PGrange 'PGint4))) where oidOf = LibPQ.Oid 3905
484−instance OidOf ('PGrange 'PGint8) where oidOf = LibPQ.Oid 3926
485−instance OidOf ('PGfixarray ns (null ('PGrange 'PGint8))) where oidOf = LibPQ.Oid 3927
486−instance OidOf ('PGvararray (null ('PGrange 'PGint8))) where oidOf = LibPQ.Oid 3927
487−instance OidOf ('PGrange 'PGnumeric) where oidOf = LibPQ.Oid 3906
488−instance OidOf ('PGfixarray ns (null ('PGrange 'PGnumeric))) where oidOf = LibPQ.Oid 3907
489−instance OidOf ('PGvararray (null ('PGrange 'PGnumeric))) where oidOf = LibPQ.Oid 3907
490−instance OidOf ('PGrange 'PGtimestamp) where oidOf = LibPQ.Oid 3908
491−instance OidOf ('PGfixarray ns (null ('PGrange 'PGtimestamp))) where oidOf = LibPQ.Oid 3909
492−instance OidOf ('PGvararray (null ('PGrange 'PGtimestamp))) where oidOf = LibPQ.Oid 3909
493−instance OidOf ('PGrange 'PGtimestamptz) where oidOf = LibPQ.Oid 3910
494−instance OidOf ('PGfixarray ns (null ('PGrange 'PGtimestamptz))) where oidOf = LibPQ.Oid 3911
495−instance OidOf ('PGvararray (null ('PGrange 'PGtimestamptz))) where oidOf = LibPQ.Oid 3911
496−instance OidOf ('PGrange 'PGdate) where oidOf = LibPQ.Oid 3912
497−instance OidOf ('PGfixarray ns (null ('PGrange 'PGdate))) where oidOf = LibPQ.Oid 3913
498−instance OidOf ('PGvararray (null ('PGrange 'PGdate))) where oidOf = LibPQ.Oid 3913
499−instance {-# OVERLAPPABLE #-} OidOf ('PGrange ty) where oidOf = LibPQ.invalidOid
500−instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGrange ty))) where oidOf = LibPQ.invalidOid
501−instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGrange ty))) where oidOf = LibPQ.invalidOid
502−instance {-# OVERLAPPABLE #-} OidOf ('PGcomposite row) where oidOf = LibPQ.invalidOid
503−instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGcomposite row))) where oidOf = LibPQ.invalidOid
504−instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGcomposite row))) where oidOf = LibPQ.invalidOid
505−instance {-# OVERLAPPABLE #-} OidOf ('PGenum labels) where oidOf = LibPQ.invalidOid
506−instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGenum labels))) where oidOf = LibPQ.invalidOid
507−instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGenum labels))) where oidOf = LibPQ.invalidOid
508−
509−class OidOfParam (ty :: NullityType) where oidOfParam :: Oid
510−instance OidOf ty => OidOfParam (null ty) where oidOfParam = oidOf @ty
511−
512−-- | Lifts a `OidOf` constraint to a field.
513−class OidOfField (field :: (Symbol, NullityType)) where
514− oidOfField :: Oid
515−instance OidOf ty => OidOfField (alias ::: nullity ty) where
516− oidOfField = oidOf @ty
517−
518−-- | A `ToNullityParam` constraint gives an encoding of a Haskell `Type` into
519−-- into the binary format of a PostgreSQL `NullityType`.
520−class ToNullityParam (x :: Type) (ty :: NullityType) where
521− toNullityParam :: x -> K (Maybe Encoding.Encoding) ty
522−instance ToParam x pg => ToNullityParam x ('NotNull pg) where
523− toNullityParam = K . Just . unK . toParam @x @pg
524−instance ToParam x pg => ToNullityParam (Maybe x) ('Null pg) where
525− toNullityParam = K . fmap (unK . toParam @x @pg)
526−
527−-- | A `ToField` constraint lifts the `ToParam` parser
528−-- to an encoding of a @(Symbol, Type)@ to a @(Symbol, NullityType)@,
529−-- encoding `Null`s to `Maybe`s. You should not define instances for
530−-- `FromField`, just use the provided instances.
531−class ToField (x :: (Symbol, Type)) (field :: (Symbol, NullityType)) where
532− toField :: P x -> K (Maybe Encoding.Encoding) field
533−instance ToNullityParam x ty => ToField (alias ::: x) (alias ::: ty) where
534− toField (P x) = K . unK $ toNullityParam @x @ty x
535−
536−-- | A `ToFixArray` constraint gives an encoding of a Haskell `Type`
537−-- into the binary format of a PostgreSQL fixed-length array.
538−-- You should not define instances for
539−-- `ToFixArray`, just use the provided instances.
540−class ToFixArray (x :: Type) (dims :: [Nat]) (array :: NullityType) where
541− toFixArray :: x -> K (K Encoding.Array dims) array
542−instance ToNullityParam x ty => ToFixArray x '[] ty where
543− toFixArray = K . K . maybe Encoding.nullArray Encoding.encodingArray . unK
544− . toNullityParam @x @ty
545−instance
546− ( IsProductType product xs
547− , Length xs ~ dim
548− , All ((~) x) xs
549− , ToFixArray x dims ty )
550− => ToFixArray product (dim ': dims) ty where
551− toFixArray = K . K . Encoding.dimensionArray foldlN
552− (unK . unK . toFixArray @x @dims @ty) . unZ . unSOP . from
553
333
554-- | A `ToParams` constraint generically sequences the encodings of `Type`s
334-- | A `ToParams` constraint generically sequences the encodings of `Type`s
555-- of the fields of a tuple or record to a row of `ColumnType`s. You should
335-- of the fields of a tuple or record to a row of `ColumnType`s. You should
556−-- not define instances of `ToParams`. Instead define `SOP.Generic` instances
336+-- not define instances of `ToParams`. Instead define `Generic` instances
557-- which in turn provide `ToParams` instances.
337-- which in turn provide `ToParams` instances.
558class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where
338class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where
559 -- | >>> type Params = '[ 'NotNull 'PGbool, 'Null 'PGint2]
339 -- | >>> type Params = '[ 'NotNull 'PGbool, 'Null 'PGint2]
@@ -565,98 +345,61 @@ class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where
565 -- >>> instance Generic Tuple
345 -- >>> instance Generic Tuple
566 -- >>> toParams @Tuple @Params (Tuple False (Just 0))
346 -- >>> toParams @Tuple @Params (Tuple False (Just 0))
567 -- K (Just "\NUL") :* K (Just "\NUL\NUL") :* Nil
347 -- K (Just "\NUL") :* K (Just "\NUL\NUL") :* Nil
568− toParams :: x -> NP (K (Maybe Encoding.Encoding)) tys
348+ toParams :: x -> NP (K (Maybe Strict.ByteString)) tys
569−instance (SListI tys, IsProductType x xs, AllZip ToNullityParam xs tys)
349+instance (SListI tys, IsProductType x xs, AllZip ToColumnParam xs tys)
570 => ToParams x tys where
350 => ToParams x tys where
571 toParams
351 toParams
572− = htrans (Proxy @ToNullityParam) (toNullityParam . unI)
352+ = htrans (Proxy @ToColumnParam) (toColumnParam . unI)
573 . unZ . unSOP . from
353 . unZ . unSOP . from
574
354
575-- | A `FromValue` constraint gives a parser from the binary format of
355-- | A `FromValue` constraint gives a parser from the binary format of
576-- a PostgreSQL `PGType` into a Haskell `Type`.
356-- a PostgreSQL `PGType` into a Haskell `Type`.
577class FromValue (pg :: PGType) (y :: Type) where
357class FromValue (pg :: PGType) (y :: Type) where
578 -- | >>> newtype Id = Id { getId :: Int16 } deriving Show
358 -- | >>> newtype Id = Id { getId :: Int16 } deriving Show
579− -- >>> instance FromValue 'PGint2 Id where fromValue = Id <$> fromValue @'PGint2
359+ -- >>> instance FromValue 'PGint2 Id where fromValue = fmap Id . fromValue
580− fromValue :: Decoding.Value y
360+ fromValue :: proxy pg -> Decoding.Value y
581−instance FromValue 'PGbool Bool where fromValue = Decoding.bool
361+instance FromValue 'PGbool Bool where fromValue _ = Decoding.bool
582−instance FromValue 'PGint2 Int16 where fromValue = Decoding.int
362+instance FromValue 'PGint2 Int16 where fromValue _ = Decoding.int
583−instance FromValue 'PGint4 Int32 where fromValue = Decoding.int
363+instance FromValue 'PGint4 Int32 where fromValue _ = Decoding.int
584−instance FromValue 'PGint8 Int64 where fromValue = Decoding.int
364+instance FromValue 'PGint8 Int64 where fromValue _ = Decoding.int
585−instance FromValue 'PGoid Word32 where fromValue = Decoding.int
586−instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4
365+instance FromValue 'PGfloat4 Float where fromValue _ = Decoding.float4
587−instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8
366+instance FromValue 'PGfloat8 Double where fromValue _ = Decoding.float8
588−instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric
367+instance FromValue 'PGnumeric Scientific where fromValue _ = Decoding.numeric
589−instance FromValue 'PGmoney Money where fromValue = Money <$> Decoding.int
590−instance FromValue 'PGuuid UUID where fromValue = Decoding.uuid
368+instance FromValue 'PGuuid UUID where fromValue _ = Decoding.uuid
591−instance FromValue 'PGinet (NetAddr IP) where fromValue = Decoding.inet
369+instance FromValue 'PGinet (NetAddr IP) where fromValue _ = Decoding.inet
592−instance FromValue ('PGchar 1) Char where fromValue = Decoding.char
370+instance FromValue ('PGchar 1) Char where fromValue _ = Decoding.char
593−instance FromValue 'PGtext Strict.Text where fromValue = Decoding.text_strict
371+instance FromValue 'PGtext Strict.Text where fromValue _ = Decoding.text_strict
594−instance FromValue 'PGtext Lazy.Text where fromValue = Decoding.text_lazy
372+instance FromValue 'PGtext Lazy.Text where fromValue _ = Decoding.text_lazy
595−instance FromValue 'PGtext String where
596− fromValue = Strict.Text.unpack <$> Decoding.text_strict
597instance FromValue 'PGbytea Strict.ByteString where
373instance FromValue 'PGbytea Strict.ByteString where
598− fromValue = Decoding.bytea_strict
374+ fromValue _ = Decoding.bytea_strict
599instance FromValue 'PGbytea Lazy.ByteString where
375instance FromValue 'PGbytea Lazy.ByteString where
600− fromValue = Decoding.bytea_lazy
376+ fromValue _ = Decoding.bytea_lazy
601−instance FromValue 'PGdate Day where fromValue = Decoding.date
377+instance FromValue 'PGdate Day where fromValue _ = Decoding.date
602−instance FromValue 'PGtime TimeOfDay where fromValue = Decoding.time_int
378+instance FromValue 'PGtime TimeOfDay where fromValue _ = Decoding.time_int
603instance FromValue 'PGtimetz (TimeOfDay, TimeZone) where
379instance FromValue 'PGtimetz (TimeOfDay, TimeZone) where
604− fromValue = Decoding.timetz_int
380+ fromValue _ = Decoding.timetz_int
605instance FromValue 'PGtimestamp LocalTime where
381instance FromValue 'PGtimestamp LocalTime where
606− fromValue = Decoding.timestamp_int
382+ fromValue _ = Decoding.timestamp_int
607instance FromValue 'PGtimestamptz UTCTime where
383instance FromValue 'PGtimestamptz UTCTime where
608− fromValue = Decoding.timestamptz_int
384+ fromValue _ = Decoding.timestamptz_int
609instance FromValue 'PGinterval DiffTime where
385instance FromValue 'PGinterval DiffTime where
610− fromValue = Decoding.interval_int
386+ fromValue _ = Decoding.interval_int
611−instance FromValue 'PGjson Aeson.Value where fromValue = Decoding.json_ast
387+instance FromValue 'PGjson Value where fromValue _ = Decoding.json_ast
612−instance FromValue 'PGjsonb Aeson.Value where fromValue = Decoding.jsonb_ast
388+instance FromValue 'PGjsonb Value where fromValue _ = Decoding.jsonb_ast
613−instance Aeson.FromJSON x => FromValue 'PGjson (Json x) where
614− fromValue = Json <$>
615− Decoding.json_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)
616−instance Aeson.FromJSON x => FromValue 'PGjsonb (Jsonb x) where
617− fromValue = Jsonb <$>
618− Decoding.jsonb_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)
619−instance FromValue pg y
620− => FromValue ('PGvararray ('NotNull pg)) (VarArray (Vector y)) where
389+instance FromValue pg y => FromValue ('PGvararray pg) (Vector (Maybe y)) where
621− fromValue =
390+ fromValue _ = Decoding.array
622− let
623− rep n x = VarArray <$> Vector.replicateM n x
624− in
625− Decoding.array $ Decoding.dimensionArray rep
391+ (Decoding.dimensionArray Vector.replicateM
626− (fromFixArray @'[] @('NotNull pg))
392+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))
627−instance FromValue pg y
628− => FromValue ('PGvararray ('Null pg)) (VarArray (Vector (Maybe y))) where
629− fromValue =
630− let
631− rep n x = VarArray <$> Vector.replicateM n x
632− in
633− Decoding.array $ Decoding.dimensionArray rep
634− (fromFixArray @'[] @('Null pg))
635−instance FromValue pg y
636− => FromValue ('PGvararray ('NotNull pg)) (VarArray [y]) where
637− fromValue =
638− let
639− rep n x = VarArray <$> replicateM n x
640− in
641− Decoding.array $ Decoding.dimensionArray rep
642− (fromFixArray @'[] @('NotNull pg))
643−instance FromValue pg y
644− => FromValue ('PGvararray ('Null pg)) (VarArray [Maybe y]) where
645− fromValue =
646− let
647− rep n x = VarArray <$> replicateM n x
648− in
649− Decoding.array $ Decoding.dimensionArray rep
650− (fromFixArray @'[] @('Null pg))
651−instance FromFixArray dims ty y
652− => FromValue ('PGfixarray dims ty) (FixArray y) where
393+instance FromValue pg y => FromValue ('PGfixarray n pg) (Vector (Maybe y)) where
653− fromValue = FixArray <$> Decoding.array (fromFixArray @dims @ty @y)
394+ fromValue _ = Decoding.array
395+ (Decoding.dimensionArray Vector.replicateM
396+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))
654instance
397instance
655 ( IsEnumType y
398 ( IsEnumType y
656 , HasDatatypeInfo y
399 , HasDatatypeInfo y
657− , LabelsPG y ~ labels
400+ , LabelsFrom y ~ labels
658− ) => FromValue ('PGenum labels) (Enumerated y) where
401+ ) => FromValue ('PGenum labels) y where
659− fromValue =
402+ fromValue _ =
660 let
403 let
661 greadConstructor
404 greadConstructor
662 :: All ((~) '[]) xss
405 :: All ((~) '[]) xss
@@ -669,16 +412,29 @@ instance
669 then Just (SOP (Z Nil))
412 then Just (SOP (Z Nil))
670 else SOP . S . unSOP <$> greadConstructor constructors name
413 else SOP . S . unSOP <$> greadConstructor constructors name
671 in
414 in
672− fmap Enumerated
673− . Decoding.enum
415+ Decoding.enum
674 $ fmap to
416 $ fmap to
675 . greadConstructor (constructorInfo (datatypeInfo (Proxy @y)))
417 . greadConstructor (constructorInfo (datatypeInfo (Proxy @y)))
676− . Strict.Text.unpack
418+ . Strict.unpack
419+
677instance
420instance
678− ( FromRow fields y
421+ ( SListI fields
422+ , MapMaybes ys
423+ , IsProductType y (Maybes ys)
424+ , AllZip FromAliasedValue fields ys
425+ , FieldNamesFrom y ~ AliasesOf fields
679− ) => FromValue ('PGcomposite fields) (Composite y) where
426+ ) => FromValue ('PGcomposite fields) y where
680 fromValue =
427 fromValue =
681 let
428 let
429+ decoders
430+ :: forall pgs zs proxy
431+ . AllZip FromAliasedValue pgs zs
432+ => proxy ('PGcomposite pgs)
433+ -> NP Decoding.Value zs
434+ decoders _ = htrans (Proxy @FromAliasedValue) fromAliasedValue
435+ (hpure Proxy :: NP Proxy pgs)
436+
437+ composite fields = do
682 -- <number of fields: 4 bytes>
438 -- <number of fields: 4 bytes>
683 -- [for each field]
439 -- [for each field]
684 -- <OID of field's type: sizeof(Oid) bytes>
440 -- <OID of field's type: sizeof(Oid) bytes>
@@ -689,133 +445,80 @@ instance
689 -- <value: <length> bytes>
445 -- <value: <length> bytes>
690 -- [end if]
446 -- [end if]
691 -- [end for]
447 -- [end for]
692− composite = Decoding.valueParser $ do
693 unitOfSize 4
448 unitOfSize 4
694− hsequence' $ hpure $ Comp $ do
449+ let
450+ each field = do
695− unitOfSize 4
451+ unitOfSize 4
696− len <- sized 4 Decoding.int
452+ len <- sized 4 Decoding.int
697− if len == -1
698− then return (K Nothing)
453+ if len == -1 then return Nothing else Just <$> sized len field
699− else K . Just <$> bytesOfSize len
454+ htraverse' each fields
700− in
455+
701− fmap Composite (Decoding.fn (fromRow @fields <=< composite))
456+ in fmap (to . SOP . Z . maybes) . composite . decoders
702
457
458+class FromAliasedValue (pg :: (Symbol,PGType)) (y :: Type) where
459+ fromAliasedValue :: proxy pg -> Decoding.Value y
460+instance FromValue pg y => FromAliasedValue (alias ::: pg) y where
461+ fromAliasedValue _ = fromValue (Proxy @pg)
462+
703−-- | A `FromField` constraint lifts the `FromValue` parser
463+-- | A `FromColumnValue` constraint lifts the `FromValue` parser
704-- to a decoding of a @(Symbol, NullityType)@ to a `Type`,
464-- to a decoding of a @(Symbol, NullityType)@ to a `Type`,
705-- decoding `Null`s to `Maybe`s. You should not define instances for
465-- decoding `Null`s to `Maybe`s. You should not define instances for
706−-- `FromField`, just use the provided instances.
466+-- `FromColumnValue`, just use the provided instances.
707−class FromField (pg :: (Symbol, NullityType)) (y :: (Symbol, Type)) where
467+class FromColumnValue (colty :: (Symbol,NullityType)) (y :: Type) where
708− fromField
468+ -- | >>> :set -XTypeOperators -XOverloadedStrings
469+ -- >>> newtype Id = Id { getId :: Int16 } deriving Show
470+ -- >>> instance FromValue 'PGint2 Id where fromValue = fmap Id . fromValue
471+ -- >>> fromColumnValue @("col" ::: 'NotNull 'PGint2) @Id (K (Just "\NUL\SOH"))
472+ -- Id {getId = 1}
473+ --
474+ -- >>> fromColumnValue @("col" ::: 'Null 'PGint2) @(Maybe Id) (K (Just "\NUL\SOH"))
475+ -- Just (Id {getId = 1})
709− :: K (Maybe Strict.ByteString) pg
476+ fromColumnValue :: K (Maybe Strict.ByteString) colty -> y
710− -> (Either Strict.Text :.: P) y
711instance FromValue pg y
477instance FromValue pg y
712− => FromField (column ::: ('NotNull pg)) (column ::: y) where
478+ => FromColumnValue (column ::: ('NotNull pg)) y where
713− fromField = Comp . \case
479+ fromColumnValue = \case
714− K Nothing -> Left "fromField: saw NULL when expecting NOT NULL"
480+ K Nothing -> error "fromColumnValue: saw NULL when expecting NOT NULL"
715− K (Just bytestring) -> P <$>
481+ K (Just bs) ->
482+ let
483+ errOrValue =
716− Decoding.valueParser (fromValue @pg) bytestring
484+ Decoding.valueParser (fromValue @pg @y Proxy) bs
485+ err str = error $ "fromColumnValue: " ++ Strict.unpack str
486+ in
487+ either err id errOrValue
717instance FromValue pg y
488instance FromValue pg y
718− => FromField (column ::: 'Null pg) (column ::: Maybe y) where
489+ => FromColumnValue (column ::: ('Null pg)) (Maybe y) where
719− fromField = Comp . \case
490+ fromColumnValue (K nullOrBytes)
720− K Nothing -> Right $ P Nothing
491+ = either err id
721− K (Just bytestring) -> P . Just <$>
492+ . Decoding.valueParser (fromValue @pg @y Proxy)
722− Decoding.valueParser (fromValue @pg) bytestring
493+ <$> nullOrBytes
723−
494+ where
724−-- | A `FromFixArray` constraint gives a decoding to a Haskell `Type`
495+ err str = error $ "fromColumnValue: " ++ Strict.unpack str
725−-- from the binary format of a PostgreSQL fixed-length array.
726−-- You should not define instances for
727−-- `FromFixArray`, just use the provided instances.
728−class FromFixArray (dims :: [Nat]) (ty :: NullityType) (y :: Type) where
729− fromFixArray :: Decoding.Array y
730−instance FromValue pg y => FromFixArray '[] ('NotNull pg) y where
731− fromFixArray = Decoding.valueArray (fromValue @pg @y)
732−instance FromValue pg y => FromFixArray '[] ('Null pg) (Maybe y) where
733− fromFixArray = Decoding.nullableValueArray (fromValue @pg @y)
734−instance
735− ( IsProductType product ys
736− , Length ys ~ dim
737− , All ((~) y) ys
738− , FromFixArray dims ty y )
739− => FromFixArray (dim ': dims) ty product where
740− fromFixArray =
741− let
742− rep _ = fmap (to . SOP . Z) . replicateMN
743− in
744− Decoding.dimensionArray rep (fromFixArray @dims @ty @y)
745
496
746-- | A `FromRow` constraint generically sequences the parsings of the columns
497-- | A `FromRow` constraint generically sequences the parsings of the columns
747−-- of a `RowType` into the fields of a record `Type` provided they have
498+-- of a `RelationType` into the fields of a record `Type` provided they have
748-- the same field names. You should not define instances of `FromRow`.
499-- the same field names. You should not define instances of `FromRow`.
749−-- Instead define `SOP.Generic` and `SOP.HasDatatypeInfo` instances which in turn
500+-- Instead define `Generic` and `HasDatatypeInfo` instances which in turn
750-- provide `FromRow` instances.
501-- provide `FromRow` instances.
751−class SListI result => FromRow (result :: RowType) y where
502+class SListI results => FromRow (results :: RelationType) y where
752 -- | >>> :set -XOverloadedStrings
503 -- | >>> :set -XOverloadedStrings
753 -- >>> import Data.Text
504 -- >>> import Data.Text
754 -- >>> newtype UserId = UserId { getUserId :: Int16 } deriving Show
505 -- >>> newtype UserId = UserId { getUserId :: Int16 } deriving Show
755− -- >>> instance FromValue 'PGint2 UserId where fromValue = UserId <$> fromValue @'PGint2
506+ -- >>> instance FromValue 'PGint2 UserId where fromValue = fmap UserId . fromValue
756 -- >>> data UserRow = UserRow { userId :: UserId, userName :: Maybe Text } deriving (Show, GHC.Generic)
507 -- >>> data UserRow = UserRow { userId :: UserId, userName :: Maybe Text } deriving (Show, GHC.Generic)
757 -- >>> instance Generic UserRow
508 -- >>> instance Generic UserRow
758 -- >>> instance HasDatatypeInfo UserRow
509 -- >>> instance HasDatatypeInfo UserRow
759 -- >>> type User = '["userId" ::: 'NotNull 'PGint2, "userName" ::: 'Null 'PGtext]
510 -- >>> type User = '["userId" ::: 'NotNull 'PGint2, "userName" ::: 'Null 'PGtext]
760 -- >>> fromRow @User @UserRow (K (Just "\NUL\SOH") :* K (Just "bloodninja") :* Nil)
511 -- >>> fromRow @User @UserRow (K (Just "\NUL\SOH") :* K (Just "bloodninja") :* Nil)
761− -- Right (UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"})
512+ -- UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"}
762− fromRow :: NP (K (Maybe Strict.ByteString)) result -> Either Strict.Text y
513+ fromRow :: NP (K (Maybe Strict.ByteString)) results -> y
763instance
514instance
764− ( SListI result
515+ ( SListI results
765− , IsRecord y ys
516+ , IsProductType y ys
766− , AllZip FromField result ys
517+ , AllZip FromColumnValue results ys
518+ , FieldNamesFrom y ~ AliasesOf results
767− ) => FromRow result y where
519+ ) => FromRow results y where
768 fromRow
520 fromRow
769− = fmap fromRecord
521+ = to . SOP . Z . htrans (Proxy @FromColumnValue) (I . fromColumnValue)
770− . hsequence'
771− . htrans (Proxy @FromField) fromField
772−------------------------------------------------------
773−-- P records
774−------------------------------------------------------
775−-- instance (FromField (col ::: pg) (col ::: hask))
776−-- => FromRow '[col ::: pg] (P (col ::: hask)) where
777−-- fromRow (pg :* Nil) = (unComp . fromField) pg
778−-- instance
779−-- ( row ~ Join row1 row2
780−-- , FromRow row1 hask1
781−-- , FromRow row2 hask2
782−-- , SListI row
783−-- ) => FromRow row (hask1, hask2) where
784−-- fromRow row = case disjoin @row1 @row2 row of
785−-- (row1, row2) -> (,) <$> fromRow row1 <*> fromRow row2
786−-- instance
787−-- ( row ~ Join row1 row23
788−-- , FromRow row1 hask1
789−-- , FromRow row23 (hask2, hask3)
790−-- , SListI row
791−-- ) => FromRow row (hask1, hask2, hask3) where
792−-- fromRow row = case disjoin @row1 @row23 row of
793−-- (row1, row23) -> do
794−-- hask1 <- fromRow row1
795−-- (hask2, hask3) <- fromRow row23
796−-- return (hask1, hask2, hask3)
797−-- instance
798−-- ( row ~ Join row1 row234
799−-- , FromRow row1 hask1
800−-- , FromRow row234 (hask2, hask3, hask4)
801−-- , SListI row
802−-- ) => FromRow row (hask1, hask2, hask3, hask4) where
803−-- fromRow row = case disjoin @row1 @row234 row of
804−-- (row1, row234) -> do
805−-- hask1 <- fromRow row1
806−-- (hask2, hask3, hask4) <- fromRow row234
807−-- return (hask1, hask2, hask3, hask4)
808−-- instance
809−-- ( row ~ Join row1 row2345
810−-- , FromRow row1 hask1
811−-- , FromRow row2345 (hask2, hask3, hask4, hask5)
812−-- , SListI row
813−-- ) => FromRow row (hask1, hask2, hask3, hask4, hask5) where
814−-- fromRow row = case disjoin @row1 @row2345 row of
815−-- (row1, row2345) -> do
816−-- hask1 <- fromRow row1
817−-- (hask2, hask3, hask4, hask5) <- fromRow row2345
818−-- return (hask1, hask2, hask3, hask4, hask5)
819
522
820-- | `Only` is a 1-tuple type, useful for encoding a single parameter with
523-- | `Only` is a 1-tuple type, useful for encoding a single parameter with
821-- `toParams` or decoding a single value with `fromRow`.
524-- `toParams` or decoding a single value with `fromRow`.
@@ -825,24 +528,8 @@ instance
825-- K (Just "foo") :* Nil
528-- K (Just "foo") :* Nil
826--
529--
827-- >>> fromRow @'["fromOnly" ::: 'Null 'PGtext] @(Only (Maybe Text)) (K (Just "bar") :* Nil)
530-- >>> fromRow @'["fromOnly" ::: 'Null 'PGtext] @(Only (Maybe Text)) (K (Just "bar") :* Nil)
828−-- Right (Only {fromOnly = Just "bar"})
531+-- Only {fromOnly = Just "bar"}
829newtype Only x = Only { fromOnly :: x }
532newtype Only x = Only { fromOnly :: x }
830 deriving (Functor,Foldable,Traversable,Eq,Ord,Read,Show,GHC.Generic)
533 deriving (Functor,Foldable,Traversable,Eq,Ord,Read,Show,GHC.Generic)
831instance Generic (Only x)
534instance Generic (Only x)
832instance HasDatatypeInfo (Only x)
535instance HasDatatypeInfo (Only x)
833−
834−foldlN
835− :: All ((~) x) xs
836− => (z -> x -> z) -> z -> NP I xs -> z
837−foldlN f z = \case
838− Nil -> z
839− I x :* xs -> let z' = f z x in seq z' $ foldlN f z' xs
840−
841−replicateMN
842− :: forall x xs m. (All ((~) x) xs, Monad m, SListI xs)
843− => m x -> m (NP I xs)
844−replicateMN mx = hsequence' $
845− hcpure (Proxy :: Proxy ((~) x)) (Comp (I <$> mx))
846−
847−getOid :: LibPQ.Oid -> Word32
848−getOid (LibPQ.Oid (CUInt oid)) = oid
squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+893−23
@@ -11,15 +11,13 @@ Squeal data definition language.
11{-# LANGUAGE
11{-# LANGUAGE
12 AllowAmbiguousTypes
12 AllowAmbiguousTypes
13 , ConstraintKinds
13 , ConstraintKinds
14− , DeriveAnyClass
15 , DeriveGeneric
14 , DeriveGeneric
16− , DerivingStrategies
17 , FlexibleContexts
15 , FlexibleContexts
18 , FlexibleInstances
16 , FlexibleInstances
19 , GADTs
17 , GADTs
18+ , GeneralizedNewtypeDeriving
20 , LambdaCase
19 , LambdaCase
21 , MultiParamTypeClasses
20 , MultiParamTypeClasses
22− , OverloadedLabels
23 , OverloadedStrings
21 , OverloadedStrings
24 , RankNTypes
22 , RankNTypes
25 , ScopedTypeVariables
23 , ScopedTypeVariables
@@ -27,56 +25,928 @@ Squeal data definition language.
27 , TypeInType
25 , TypeInType
28 , TypeOperators
26 , TypeOperators
29 , UndecidableSuperClasses
27 , UndecidableSuperClasses
30− , UndecidableInstances
31#-}
28#-}
32
29
33module Squeal.PostgreSQL.Definition
30module Squeal.PostgreSQL.Definition
34 ( -- * Definition
31 ( -- * Definition
35− Definition (..)
32+ Definition (UnsafeDefinition, renderDefinition)
36 , (>>>)
33 , (>>>)
37− , manipDefinition
34+ -- * Tables
35+ -- ** Create
36+ , createTable
37+ , createTableIfNotExists
38+ , TableConstraintExpression (..)
39+ , check
40+ , unique
41+ , primaryKey
42+ , foreignKey
43+ , ForeignKeyed
44+ , OnDeleteClause (OnDeleteNoAction, OnDeleteRestrict, OnDeleteCascade)
45+ , renderOnDeleteClause
46+ , OnUpdateClause (OnUpdateNoAction, OnUpdateRestrict, OnUpdateCascade)
47+ , renderOnUpdateClause
48+ -- ** Drop
49+ , dropTable
50+ -- ** Alter
51+ , alterTable
52+ , alterTableRename
53+ , AlterTable (UnsafeAlterTable, renderAlterTable)
54+ , addConstraint
55+ , dropConstraint
56+ , AddColumn (addColumn)
57+ , dropColumn
58+ , renameColumn
59+ , alterColumn
60+ , AlterColumn (UnsafeAlterColumn, renderAlterColumn)
61+ , setDefault
62+ , dropDefault
63+ , setNotNull
64+ , dropNotNull
65+ , alterType
66+ -- * Views
67+ , createView
68+ , dropView
69+ -- * Types
70+ , createTypeEnum
71+ , createTypeEnumFrom
72+ , createTypeComposite
73+ , createTypeCompositeFrom
74+ , dropType
75+ -- * Columns
76+ , ColumnTypeExpression (..)
77+ , nullable
78+ , notNullable
79+ , default_
80+ , serial2
81+ , smallserial
82+ , serial4
83+ , serial
84+ , serial8
85+ , bigserial
38 ) where
86 ) where
39
87
40import Control.Category
88import Control.Category
41import Control.DeepSeq
89import Control.DeepSeq
42import Data.ByteString
90import Data.ByteString
43import Data.Monoid
91import Data.Monoid
92+import GHC.TypeLits
44import Prelude hiding ((.), id)
93import Prelude hiding ((.), id)
45
94
95+import qualified Generics.SOP as SOP
46import qualified GHC.Generics as GHC
96import qualified GHC.Generics as GHC
47
97
48−import Squeal.PostgreSQL.Manipulation
98+import Squeal.PostgreSQL.Expression
99+import Squeal.PostgreSQL.Query
49import Squeal.PostgreSQL.Render
100import Squeal.PostgreSQL.Render
50import Squeal.PostgreSQL.Schema
101import Squeal.PostgreSQL.Schema
51
102
52−-- $setup
53−-- >>> import Squeal.PostgreSQL
54−
55{-----------------------------------------
103{-----------------------------------------
56statements
104statements
57-----------------------------------------}
105-----------------------------------------}
58
106
59−-- | A `Definition` is a statement that changes the schemas of the
107+-- | A `Definition` is a statement that changes the schema of the
60-- database, like a `createTable`, `dropTable`, or `alterTable` command.
108-- database, like a `createTable`, `dropTable`, or `alterTable` command.
61-- `Definition`s may be composed using the `>>>` operator.
109-- `Definition`s may be composed using the `>>>` operator.
62newtype Definition
110newtype Definition
63− (schemas0 :: SchemasType)
111+ (schema0 :: SchemaType)
64− (schemas1 :: SchemasType)
112+ (schema1 :: SchemaType)
65 = UnsafeDefinition { renderDefinition :: ByteString }
113 = UnsafeDefinition { renderDefinition :: ByteString }
66 deriving (GHC.Generic,Show,Eq,Ord,NFData)
114 deriving (GHC.Generic,Show,Eq,Ord,NFData)
67
115
68−instance RenderSQL (Definition schemas0 schemas1) where
116+instance RenderSQL (Definition schema0 schema1) where
69 renderSQL = renderDefinition
117 renderSQL = renderDefinition
70
118
71instance Category Definition where
119instance Category Definition where
72 id = UnsafeDefinition ";"
120 id = UnsafeDefinition ";"
73 ddl1 . ddl0 = UnsafeDefinition $
121 ddl1 . ddl0 = UnsafeDefinition $
74− renderSQL ddl0 <> "\n" <> renderSQL ddl1
122+ renderDefinition ddl0 <> "\n" <> renderDefinition ddl1
75−
123+
76−-- | A `Manipulation` without input or output can be run as a statement
124+{-----------------------------------------
77−-- along with other `Definition`s, by embedding it using `manipDefinition`.
125+CREATE statements
78−manipDefinition
126+-----------------------------------------}
79− :: Manipulation '[] schemas '[] '[]
127+
80− -- ^ no input or output
128+{- | `createTable` adds a table to the schema.
81− -> Definition schemas schemas
129+
82−manipDefinition = UnsafeDefinition . (<> ";") . renderSQL
130+>>> :set -XOverloadedLabels
131+>>> :{
132+printSQL $
133+ createTable #tab ((int & nullable) `As` #a :* (real & nullable) `As` #b :* Nil) Nil
134+:}
135+CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
136+-}
137+createTable
138+ :: ( KnownSymbol table
139+ , columns ~ (col ': cols)
140+ , SOP.SListI columns
141+ , SOP.SListI constraints
142+ , schema1 ~ Create table ('Table (constraints :=> columns)) schema0 )
143+ => Alias table -- ^ the name of the table to add
144+ -> NP (Aliased (ColumnTypeExpression schema0)) columns
145+ -- ^ the names and datatype of each column
146+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints
147+ -- ^ constraints that must hold for the table
148+ -> Definition schema0 schema1
149+createTable tab columns constraints = UnsafeDefinition $
150+ "CREATE TABLE" <+> renderCreation tab columns constraints
151+
152+{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.
153+Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.
154+`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in
155+the `Category` of `Definition`s.
156+
157+>>> :set -XOverloadedLabels -XTypeApplications
158+>>> type Table = '[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGfloat4]
159+>>> type Schema = '["tab" ::: 'Table Table]
160+>>> :{
161+let
162+ setup :: Definition Schema Schema
163+ setup = createTableIfNotExists #tab ((int & nullable) `As` #a :* (real & nullable) `As` #b :* Nil) Nil
164+in printSQL setup
165+:}
166+CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);
167+-}
168+createTableIfNotExists
169+ :: ( Has table schema ('Table (constraints :=> columns))
170+ , SOP.SListI columns
171+ , SOP.SListI constraints )
172+ => Alias table -- ^ the name of the table to add
173+ -> NP (Aliased (ColumnTypeExpression schema)) columns
174+ -- ^ the names and datatype of each column
175+ -> NP (Aliased (TableConstraintExpression schema table)) constraints
176+ -- ^ constraints that must hold for the table
177+ -> Definition schema schema
178+createTableIfNotExists tab columns constraints = UnsafeDefinition $
179+ "CREATE TABLE IF NOT EXISTS"
180+ <+> renderCreation tab columns constraints
181+
182+-- helper function for `createTable` and `createTableIfNotExists`
183+renderCreation
184+ :: ( KnownSymbol table
185+ , SOP.SListI columns
186+ , SOP.SListI constraints )
187+ => Alias table -- ^ the name of the table to add
188+ -> NP (Aliased (ColumnTypeExpression schema0)) columns
189+ -- ^ the names and datatype of each column
190+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints
191+ -- ^ constraints that must hold for the table
192+ -> ByteString
193+renderCreation tab columns constraints = renderAlias tab
194+ <+> parenthesized
195+ ( renderCommaSeparated renderColumnDef columns
196+ <> ( case constraints of
197+ Nil -> ""
198+ _ -> ", " <>
199+ renderCommaSeparated renderConstraint constraints ) )
200+ <> ";"
201+ where
202+ renderColumnDef :: Aliased (ColumnTypeExpression schema) x -> ByteString
203+ renderColumnDef (ty `As` column) =
204+ renderAlias column <+> renderColumnTypeExpression ty
205+ renderConstraint
206+ :: Aliased (TableConstraintExpression schema columns) constraint
207+ -> ByteString
208+ renderConstraint (constraint `As` alias) =
209+ "CONSTRAINT" <+> renderAlias alias <+> renderTableConstraintExpression constraint
210+
211+-- | Data types are a way to limit the kind of data that can be stored in a
212+-- table. For many applications, however, the constraint they provide is
213+-- too coarse. For example, a column containing a product price should
214+-- probably only accept positive values. But there is no standard data type
215+-- that accepts only positive numbers. Another issue is that you might want
216+-- to constrain column data with respect to other columns or rows.
217+-- For example, in a table containing product information,
218+-- there should be only one row for each product number.
219+-- `TableConstraint`s give you as much control over the data in your tables
220+-- as you wish. If a user attempts to store data in a column that would
221+-- violate a constraint, an error is raised. This applies
222+-- even if the value came from the default value definition.
223+newtype TableConstraintExpression
224+ (schema :: SchemaType)
225+ (table :: Symbol)
226+ (tableConstraint :: TableConstraint)
227+ = UnsafeTableConstraintExpression
228+ { renderTableConstraintExpression :: ByteString }
229+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
230+
231+{-| A `check` constraint is the most generic `TableConstraint` type.
232+It allows you to specify that the value in a certain column must satisfy
233+a Boolean (truth-value) expression.
234+
235+>>> :{
236+type Schema = '[
237+ "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[
238+ "a" ::: 'NoDef :=> 'NotNull 'PGint4,
239+ "b" ::: 'NoDef :=> 'NotNull 'PGint4
240+ ])]
241+:}
242+
243+>>> :{
244+let
245+ definition :: Definition '[] Schema
246+ definition = createTable #tab
247+ ( (int & notNullable) `As` #a :*
248+ (int & notNullable) `As` #b :* Nil )
249+ ( check (#a :* #b :* Nil) (#a .> #b) `As` #inequality :* Nil )
250+:}
251+
252+>>> printSQL definition
253+CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));
254+-}
255+check
256+ :: ( Has alias schema ('Table table)
257+ , HasAll aliases (TableToRelation table) subcolumns )
258+ => NP Alias aliases
259+ -- ^ specify the subcolumns which are getting checked
260+ -> (forall tab. Condition schema '[tab ::: subcolumns] 'Ungrouped '[])
261+ -- ^ a closed `Condition` on those subcolumns
262+ -> TableConstraintExpression schema alias ('Check aliases)
263+check _cols condition = UnsafeTableConstraintExpression $
264+ "CHECK" <+> parenthesized (renderExpression condition)
265+
266+{-| A `unique` constraint ensure that the data contained in a column,
267+or a group of columns, is unique among all the rows in the table.
268+
269+>>> :{
270+type Schema = '[
271+ "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[
272+ "a" ::: 'NoDef :=> 'Null 'PGint4,
273+ "b" ::: 'NoDef :=> 'Null 'PGint4
274+ ])]
275+:}
276+
277+>>> :{
278+let
279+ definition :: Definition '[] Schema
280+ definition = createTable #tab
281+ ( (int & nullable) `As` #a :*
282+ (int & nullable) `As` #b :* Nil )
283+ ( unique (#a :* #b :* Nil) `As` #uq_a_b :* Nil )
284+:}
285+
286+>>> printSQL definition
287+CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));
288+-}
289+unique
290+ :: ( Has alias schema ('Table table)
291+ , HasAll aliases (TableToRelation table) subcolumns )
292+ => NP Alias aliases
293+ -- ^ specify subcolumns which together are unique for each row
294+ -> TableConstraintExpression schema alias ('Unique aliases)
295+unique columns = UnsafeTableConstraintExpression $
296+ "UNIQUE" <+> parenthesized (commaSeparated (renderAliases columns))
297+
298+{-| A `primaryKey` constraint indicates that a column, or group of columns,
299+can be used as a unique identifier for rows in the table.
300+This requires that the values be both unique and not null.
301+
302+>>> :{
303+type Schema = '[
304+ "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[
305+ "id" ::: 'Def :=> 'NotNull 'PGint4,
306+ "name" ::: 'NoDef :=> 'NotNull 'PGtext
307+ ])]
308+:}
309+
310+>>> :{
311+let
312+ definition :: Definition '[] Schema
313+ definition = createTable #tab
314+ ( serial `As` #id :*
315+ (text & notNullable) `As` #name :* Nil )
316+ ( primaryKey #id `As` #pk_id :* Nil )
317+:}
318+
319+>>> printSQL definition
320+CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));
321+-}
322+primaryKey
323+ :: ( Has alias schema ('Table table)
324+ , HasAll aliases (TableToColumns table) subcolumns
325+ , AllNotNull subcolumns )
326+ => NP Alias aliases
327+ -- ^ specify the subcolumns which together form a primary key.
328+ -> TableConstraintExpression schema alias ('PrimaryKey aliases)
329+primaryKey columns = UnsafeTableConstraintExpression $
330+ "PRIMARY KEY" <+> parenthesized (commaSeparated (renderAliases columns))
331+
332+{-| A `foreignKey` specifies that the values in a column
333+(or a group of columns) must match the values appearing in some row of
334+another table. We say this maintains the referential integrity
335+between two related tables.
336+
337+>>> :{
338+type Schema =
339+ '[ "users" ::: 'Table (
340+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
341+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
342+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
343+ ])
344+ , "emails" ::: 'Table (
345+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
346+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
347+ ] :=>
348+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
349+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
350+ , "email" ::: 'NoDef :=> 'Null 'PGtext
351+ ])
352+ ]
353+:}
354+
355+>>> :{
356+let
357+ setup :: Definition '[] Schema
358+ setup =
359+ createTable #users
360+ ( serial `As` #id :*
361+ (text & notNullable) `As` #name :* Nil )
362+ ( primaryKey #id `As` #pk_users :* Nil ) >>>
363+ createTable #emails
364+ ( serial `As` #id :*
365+ (int & notNullable) `As` #user_id :*
366+ (text & nullable) `As` #email :* Nil )
367+ ( primaryKey #id `As` #pk_emails :*
368+ foreignKey #user_id #users #id
369+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
370+in printSQL setup
371+:}
372+CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
373+CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
374+
375+A `foreignKey` can even be a table self-reference.
376+
377+>>> :{
378+type Schema =
379+ '[ "employees" ::: 'Table (
380+ '[ "employees_pk" ::: 'PrimaryKey '["id"]
381+ , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]
382+ ] :=>
383+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
384+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
385+ , "employer_id" ::: 'NoDef :=> 'Null 'PGint4
386+ ])
387+ ]
388+:}
389+
390+>>> :{
391+let
392+ setup :: Definition '[] Schema
393+ setup =
394+ createTable #employees
395+ ( serial `As` #id :*
396+ (text & notNullable) `As` #name :*
397+ (integer & nullable) `As` #employer_id :* Nil )
398+ ( primaryKey #id `As` #employees_pk :*
399+ foreignKey #employer_id #employees #id
400+ OnDeleteCascade OnUpdateCascade `As` #employees_employer_fk :* Nil )
401+in printSQL setup
402+:}
403+CREATE TABLE "employees" ("id" serial, "name" text NOT NULL, "employer_id" integer NULL, CONSTRAINT "employees_pk" PRIMARY KEY ("id"), CONSTRAINT "employees_employer_fk" FOREIGN KEY ("employer_id") REFERENCES "employees" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
404+-}
405+foreignKey
406+ :: (ForeignKeyed schema child parent
407+ table reftable
408+ columns refcolumns
409+ constraints cols
410+ reftys tys )
411+ => NP Alias columns
412+ -- ^ column or columns in the table
413+ -> Alias parent
414+ -- ^ reference table
415+ -> NP Alias refcolumns
416+ -- ^ reference column or columns in the reference table
417+ -> OnDeleteClause
418+ -- ^ what to do when reference is deleted
419+ -> OnUpdateClause
420+ -- ^ what to do when reference is updated
421+ -> TableConstraintExpression schema child
422+ ('ForeignKey columns parent refcolumns)
423+foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $
424+ "FOREIGN KEY" <+> parenthesized (commaSeparated (renderAliases keys))
425+ <+> "REFERENCES" <+> renderAlias parent
426+ <+> parenthesized (commaSeparated (renderAliases refs))
427+ <+> renderOnDeleteClause ondel
428+ <+> renderOnUpdateClause onupd
429+
430+-- | A constraint synonym between types involved in a foreign key constraint.
431+type ForeignKeyed schema
432+ child parent
433+ table reftable
434+ columns refcolumns
435+ constraints cols
436+ reftys tys =
437+ ( Has child schema ('Table table)
438+ , Has parent schema ('Table reftable)
439+ , HasAll columns (TableToColumns table) tys
440+ , reftable ~ (constraints :=> cols)
441+ , HasAll refcolumns cols reftys
442+ , SOP.AllZip SamePGType tys reftys
443+ , Uniquely refcolumns constraints )
444+
445+-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.
446+data OnDeleteClause
447+ = OnDeleteNoAction
448+ -- ^ if any referencing rows still exist when the constraint is checked,
449+ -- an error is raised
450+ | OnDeleteRestrict -- ^ prevents deletion of a referenced row
451+ | OnDeleteCascade
452+ -- ^ specifies that when a referenced row is deleted,
453+ -- row(s) referencing it should be automatically deleted as well
454+ deriving (GHC.Generic,Show,Eq,Ord)
455+instance NFData OnDeleteClause
456+
457+-- | Render `OnDeleteClause`.
458+renderOnDeleteClause :: OnDeleteClause -> ByteString
459+renderOnDeleteClause = \case
460+ OnDeleteNoAction -> "ON DELETE NO ACTION"
461+ OnDeleteRestrict -> "ON DELETE RESTRICT"
462+ OnDeleteCascade -> "ON DELETE CASCADE"
463+
464+-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked
465+-- when a referenced column is changed (updated).
466+data OnUpdateClause
467+ = OnUpdateNoAction
468+ -- ^ if any referencing rows has not changed when the constraint is checked,
469+ -- an error is raised
470+ | OnUpdateRestrict -- ^ prevents update of a referenced row
471+ | OnUpdateCascade
472+ -- ^ the updated values of the referenced column(s) should be copied
473+ -- into the referencing row(s)
474+ deriving (GHC.Generic,Show,Eq,Ord)
475+instance NFData OnUpdateClause
476+
477+-- | Render `OnUpdateClause`.
478+renderOnUpdateClause :: OnUpdateClause -> ByteString
479+renderOnUpdateClause = \case
480+ OnUpdateNoAction -> "ON UPDATE NO ACTION"
481+ OnUpdateRestrict -> "ON UPDATE RESTRICT"
482+ OnUpdateCascade -> "ON UPDATE CASCADE"
483+
484+{-----------------------------------------
485+DROP statements
486+-----------------------------------------}
487+
488+-- | `dropTable` removes a table from the schema.
489+--
490+-- >>> :{
491+-- let
492+-- definition :: Definition '["muh_table" ::: 'Table t] '[]
493+-- definition = dropTable #muh_table
494+-- :}
495+--
496+-- >>> printSQL definition
497+-- DROP TABLE "muh_table";
498+dropTable
499+ :: Has table schema ('Table t)
500+ => Alias table -- ^ table to remove
501+ -> Definition schema (Drop table schema)
502+dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderAlias tab <> ";"
503+
504+{-----------------------------------------
505+ALTER statements
506+-----------------------------------------}
507+
508+-- | `alterTable` changes the definition of a table from the schema.
509+alterTable
510+ :: KnownSymbol alias
511+ => Alias alias -- ^ table to alter
512+ -> AlterTable alias table schema -- ^ alteration to perform
513+ -> Definition schema (Alter alias ('Table table) schema)
514+alterTable tab alteration = UnsafeDefinition $
515+ "ALTER TABLE"
516+ <+> renderAlias tab
517+ <+> renderAlterTable alteration
518+ <> ";"
519+
520+-- | `alterTableRename` changes the name of a table from the schema.
521+--
522+-- >>> printSQL $ alterTableRename #foo #bar
523+-- ALTER TABLE "foo" RENAME TO "bar";
524+alterTableRename
525+ :: (KnownSymbol table0, KnownSymbol table1)
526+ => Alias table0 -- ^ table to rename
527+ -> Alias table1 -- ^ what to rename it
528+ -> Definition schema (Rename table0 table1 schema)
529+alterTableRename table0 table1 = UnsafeDefinition $
530+ "ALTER TABLE" <+> renderAlias table0
531+ <+> "RENAME TO" <+> renderAlias table1 <> ";"
532+
533+-- | An `AlterTable` describes the alteration to perform on the columns
534+-- of a table.
535+newtype AlterTable
536+ (alias :: Symbol)
537+ (table :: TableType)
538+ (schema :: SchemaType) =
539+ UnsafeAlterTable {renderAlterTable :: ByteString}
540+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
541+
542+-- | An `addConstraint` adds a table constraint.
543+--
544+-- >>> :{
545+-- let
546+-- definition :: Definition
547+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
548+-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
549+-- definition = alterTable #tab (addConstraint #positive (check (#col :* Nil) (#col .> 0)))
550+-- in printSQL definition
551+-- :}
552+-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));
553+addConstraint
554+ :: ( KnownSymbol alias
555+ , Has tab schema ('Table table0)
556+ , table0 ~ (constraints :=> columns)
557+ , table1 ~ (Create alias constraint constraints :=> columns) )
558+ => Alias alias
559+ -> TableConstraintExpression schema tab constraint
560+ -- ^ constraint to add
561+ -> AlterTable tab table1 schema
562+addConstraint alias constraint = UnsafeAlterTable $
563+ "ADD" <+> "CONSTRAINT" <+> renderAlias alias
564+ <+> renderTableConstraintExpression constraint
565+
566+-- | A `dropConstraint` drops a table constraint.
567+--
568+-- >>> :{
569+-- let
570+-- definition :: Definition
571+-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
572+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
573+-- definition = alterTable #tab (dropConstraint #positive)
574+-- in printSQL definition
575+-- :}
576+-- ALTER TABLE "tab" DROP CONSTRAINT "positive";
577+dropConstraint
578+ :: ( KnownSymbol constraint
579+ , Has tab schema ('Table table0)
580+ , table0 ~ (constraints :=> columns)
581+ , table1 ~ (Drop constraint constraints :=> columns) )
582+ => Alias constraint
583+ -- ^ constraint to drop
584+ -> AlterTable tab table1 schema
585+dropConstraint constraint = UnsafeAlterTable $
586+ "DROP" <+> "CONSTRAINT" <+> renderAlias constraint
587+
588+-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.
589+class AddColumn ty where
590+ -- | `addColumn` adds a new column, initially filled with whatever
591+ -- default value is given or with @NULL@.
592+ --
593+ -- >>> :{
594+ -- let
595+ -- definition :: Definition
596+ -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
597+ -- '["tab" ::: 'Table ('[] :=>
598+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
599+ -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]
600+ -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))
601+ -- in printSQL definition
602+ -- :}
603+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';
604+ --
605+ -- >>> :{
606+ -- let
607+ -- definition :: Definition
608+ -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
609+ -- '["tab" ::: 'Table ('[] :=>
610+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
611+ -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]
612+ -- definition = alterTable #tab (addColumn #col2 (text & nullable))
613+ -- in printSQL definition
614+ -- :}
615+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;
616+ addColumn
617+ :: ( KnownSymbol column
618+ , Has tab schema ('Table table0)
619+ , table0 ~ (constraints :=> columns)
620+ , table1 ~ (constraints :=> Create column ty columns) )
621+ => Alias column -- ^ column to add
622+ -> ColumnTypeExpression schema ty -- ^ type of the new column
623+ -> AlterTable tab table1 schema
624+ addColumn column ty = UnsafeAlterTable $
625+ "ADD COLUMN" <+> renderAlias column <+> renderColumnTypeExpression ty
626+instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)
627+instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)
628+
629+-- | A `dropColumn` removes a column. Whatever data was in the column
630+-- disappears. Table constraints involving the column are dropped, too.
631+-- However, if the column is referenced by a foreign key constraint of
632+-- another table, PostgreSQL will not silently drop that constraint.
633+--
634+-- >>> :{
635+-- let
636+-- definition :: Definition
637+-- '["tab" ::: 'Table ('[] :=>
638+-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
639+-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]
640+-- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
641+-- definition = alterTable #tab (dropColumn #col2)
642+-- in printSQL definition
643+-- :}
644+-- ALTER TABLE "tab" DROP COLUMN "col2";
645+dropColumn
646+ :: ( KnownSymbol column
647+ , Has tab schema ('Table table0)
648+ , table0 ~ (constraints :=> columns)
649+ , table1 ~ (constraints :=> Drop column columns) )
650+ => Alias column -- ^ column to remove
651+ -> AlterTable tab table1 schema
652+dropColumn column = UnsafeAlterTable $
653+ "DROP COLUMN" <+> renderAlias column
654+
655+-- | A `renameColumn` renames a column.
656+--
657+-- >>> :{
658+-- let
659+-- definition :: Definition
660+-- '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]
661+-- '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]
662+-- definition = alterTable #tab (renameColumn #foo #bar)
663+-- in printSQL definition
664+-- :}
665+-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";
666+renameColumn
667+ :: ( KnownSymbol column0
668+ , KnownSymbol column1
669+ , Has tab schema ('Table table0)
670+ , table0 ~ (constraints :=> columns)
671+ , table1 ~ (constraints :=> Rename column0 column1 columns) )
672+ => Alias column0 -- ^ column to rename
673+ -> Alias column1 -- ^ what to rename the column
674+ -> AlterTable tab table1 schema
675+renameColumn column0 column1 = UnsafeAlterTable $
676+ "RENAME COLUMN" <+> renderAlias column0 <+> "TO" <+> renderAlias column1
677+
678+-- | An `alterColumn` alters a single column.
679+alterColumn
680+ :: ( KnownSymbol column
681+ , Has tab schema ('Table table0)
682+ , table0 ~ (constraints :=> columns)
683+ , Has column columns ty0
684+ , tables1 ~ (constraints :=> Alter column ty1 columns))
685+ => Alias column -- ^ column to alter
686+ -> AlterColumn schema ty0 ty1 -- ^ alteration to perform
687+ -> AlterTable tab table1 schema
688+alterColumn column alteration = UnsafeAlterTable $
689+ "ALTER COLUMN" <+> renderAlias column <+> renderAlterColumn alteration
690+
691+-- | An `AlterColumn` describes the alteration to perform on a single column.
692+newtype AlterColumn (schema :: SchemaType) (ty0 :: ColumnType) (ty1 :: ColumnType) =
693+ UnsafeAlterColumn {renderAlterColumn :: ByteString}
694+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
695+
696+-- | A `setDefault` sets a new default for a column. Note that this doesn't
697+-- affect any existing rows in the table, it just changes the default for
698+-- future insert and update commands.
699+--
700+-- >>> :{
701+-- let
702+-- definition :: Definition
703+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
704+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]
705+-- definition = alterTable #tab (alterColumn #col (setDefault 5))
706+-- in printSQL definition
707+-- :}
708+-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;
709+setDefault
710+ :: Expression schema '[] 'Ungrouped '[] ty -- ^ default value to set
711+ -> AlterColumn schema (constraint :=> ty) ('Def :=> ty)
712+setDefault expression = UnsafeAlterColumn $
713+ "SET DEFAULT" <+> renderExpression expression
714+
715+-- | A `dropDefault` removes any default value for a column.
716+--
717+-- >>> :{
718+-- let
719+-- definition :: Definition
720+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]
721+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
722+-- definition = alterTable #tab (alterColumn #col dropDefault)
723+-- in printSQL definition
724+-- :}
725+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;
726+dropDefault :: AlterColumn schema ('Def :=> ty) ('NoDef :=> ty)
727+dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"
728+
729+-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.
730+-- The constraint will be checked immediately, so the table data must satisfy
731+-- the constraint before it can be added.
732+--
733+-- >>> :{
734+-- let
735+-- definition :: Definition
736+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
737+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
738+-- definition = alterTable #tab (alterColumn #col setNotNull)
739+-- in printSQL definition
740+-- :}
741+-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;
742+setNotNull
743+ :: AlterColumn schema (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)
744+setNotNull = UnsafeAlterColumn $ "SET NOT NULL"
745+
746+-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.
747+--
748+-- >>> :{
749+-- let
750+-- definition :: Definition
751+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
752+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
753+-- definition = alterTable #tab (alterColumn #col dropNotNull)
754+-- in printSQL definition
755+-- :}
756+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;
757+dropNotNull
758+ :: AlterColumn schema (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)
759+dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"
760+
761+-- | An `alterType` converts a column to a different data type.
762+-- This will succeed only if each existing entry in the column can be
763+-- converted to the new type by an implicit cast.
764+--
765+-- >>> :{
766+-- let
767+-- definition :: Definition
768+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
769+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]
770+-- definition =
771+-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))
772+-- in printSQL definition
773+-- :}
774+-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;
775+alterType :: ColumnTypeExpression schema ty -> AlterColumn schema ty0 ty
776+alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty
777+
778+-- | Create a view.
779+--
780+-- >>> :{
781+-- let
782+-- definition :: Definition
783+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]
784+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
785+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]
786+-- definition =
787+-- createView #bc (select (#b :* #c :* Nil) (from (table #abc)))
788+-- in printSQL definition
789+-- :}
790+-- CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";
791+createView
792+ :: KnownSymbol view
793+ => Alias view -- ^ the name of the view to add
794+ -> Query schema '[] relation
795+ -- ^ query
796+ -> Definition schema (Create view ('View relation) schema)
797+createView alias query = UnsafeDefinition $
798+ "CREATE" <+> "VIEW" <+> renderAlias alias <+> "AS"
799+ <+> renderQuery query <> ";"
800+
801+-- | Drop a view.
802+--
803+-- >>> :{
804+-- let
805+-- definition :: Definition
806+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
807+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]
808+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]
809+-- definition = dropView #bc
810+-- in printSQL definition
811+-- :}
812+-- DROP VIEW "bc";
813+dropView
814+ :: Has view schema ('View v)
815+ => Alias view -- ^ view to remove
816+ -> Definition schema (Drop view schema)
817+dropView v = UnsafeDefinition $ "DROP VIEW" <+> renderAlias v <> ";"
818+
819+-- | Enumerated types are created using the `createTypeEnum` command, for example
820+--
821+-- >>> printSQL $ createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy" :* Nil)
822+-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');
823+createTypeEnum
824+ :: (KnownSymbol enum, SOP.All KnownSymbol labels)
825+ => Alias enum
826+ -- ^ name of the user defined enumerated type
827+ -> NP PGlabel labels
828+ -- ^ labels of the enumerated type
829+ -> Definition schema (Create enum ('Typedef ('PGenum labels)) schema)
830+createTypeEnum enum labels = UnsafeDefinition $
831+ "CREATE" <+> "TYPE" <+> renderAlias enum <+> "AS" <+> "ENUM" <+>
832+ parenthesized (commaSeparated (renderLabels labels)) <> ";"
833+
834+-- | Enumerated types can also be generated from a Haskell type, for example
835+--
836+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
837+-- >>> instance SOP.Generic Schwarma
838+-- >>> instance SOP.HasDatatypeInfo Schwarma
839+-- >>> printSQL $ createTypeEnumFrom @Schwarma #schwarma
840+-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');
841+createTypeEnumFrom
842+ :: forall hask enum schema.
843+ ( SOP.Generic hask
844+ , SOP.All KnownSymbol (LabelsFrom hask)
845+ , KnownSymbol enum
846+ )
847+ => Alias enum
848+ -- ^ name of the user defined enumerated type
849+ -> Definition schema (Create enum ('Typedef (EnumFrom hask)) schema)
850+createTypeEnumFrom enum = createTypeEnum enum
851+ (SOP.hpure label :: NP PGlabel (LabelsFrom hask))
852+
853+-- | `createTypeComposite` creates a composite type. The composite type is
854+-- specified by a list of attribute names and data types.
855+--
856+-- >>> printSQL $ createTypeComposite #complex (float8 `As` #real :* float8 `As` #imaginary :* Nil)
857+-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
858+createTypeComposite
859+ :: (KnownSymbol ty, SOP.SListI fields)
860+ => Alias ty
861+ -- ^ name of the user defined composite type
862+ -> NP (Aliased (TypeExpression schema)) fields
863+ -- ^ list of attribute names and data types
864+ -> Definition schema (Create ty ('Typedef ('PGcomposite fields)) schema)
865+createTypeComposite ty fields = UnsafeDefinition $
866+ "CREATE" <+> "TYPE" <+> renderAlias ty <+> "AS" <+> parenthesized
867+ (renderCommaSeparated renderField fields) <> ";"
868+ where
869+ renderField :: Aliased (TypeExpression schema) x -> ByteString
870+ renderField (typ `As` field) =
871+ renderAlias field <+> renderTypeExpression typ
872+
873+-- | Composite types can also be generated from a Haskell type, for example
874+--
875+-- >>> data Complex = Complex {real :: Maybe Double, imaginary :: Maybe Double} deriving GHC.Generic
876+-- >>> instance SOP.Generic Complex
877+-- >>> instance SOP.HasDatatypeInfo Complex
878+-- >>> printSQL $ createTypeCompositeFrom @Complex #complex
879+-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
880+createTypeCompositeFrom
881+ :: forall hask ty schema.
882+ ( ZipAliased (FieldNamesFrom hask) (FieldTypesFrom hask)
883+ , SOP.All (PGTyped schema) (FieldTypesFrom hask)
884+ , KnownSymbol ty
885+ )
886+ => Alias ty
887+ -- ^ name of the user defined composite type
888+ -> Definition schema (Create ty ( 'Typedef (CompositeFrom hask)) schema)
889+createTypeCompositeFrom ty = createTypeComposite ty $ zipAs
890+ (SOP.hpure Alias :: NP Alias (FieldNamesFrom hask))
891+ (SOP.hcpure (SOP.Proxy :: SOP.Proxy (PGTyped schema)) pgtype
892+ :: NP (TypeExpression schema) (FieldTypesFrom hask))
893+
894+-- | Drop a type.
895+--
896+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
897+-- >>> instance SOP.Generic Schwarma
898+-- >>> instance SOP.HasDatatypeInfo Schwarma
899+-- >>> printSQL (dropType #schwarma :: Definition '["schwarma" ::: 'Typedef (EnumFrom Schwarma)] '[])
900+-- DROP TYPE "schwarma";
901+dropType
902+ :: Has tydef schema ('Typedef ty)
903+ => Alias tydef
904+ -- ^ name of the user defined type
905+ -> Definition schema (Drop tydef schema)
906+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderAlias tydef <> ";"
907+
908+-- | `ColumnTypeExpression`s are used in `createTable` commands.
909+newtype ColumnTypeExpression (schema :: SchemaType) (ty :: ColumnType)
910+ = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }
911+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
912+
913+-- | used in `createTable` commands as a column constraint to note that
914+-- @NULL@ may be present in a column
915+nullable
916+ :: TypeExpression schema ty
917+ -> ColumnTypeExpression schema ('NoDef :=> 'Null ty)
918+nullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NULL"
919+
920+-- | used in `createTable` commands as a column constraint to ensure
921+-- @NULL@ is not present in a column
922+notNullable
923+ :: TypeExpression schema ty
924+ -> ColumnTypeExpression schema (def :=> 'NotNull ty)
925+notNullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NOT NULL"
926+
927+-- | used in `createTable` commands as a column constraint to give a default
928+default_
929+ :: Expression schema '[] 'Ungrouped '[] ty
930+ -> ColumnTypeExpression schema ('NoDef :=> ty)
931+ -> ColumnTypeExpression schema ('Def :=> ty)
932+default_ x ty = UnsafeColumnTypeExpression $
933+ renderColumnTypeExpression ty <+> "DEFAULT" <+> renderExpression x
934+
935+-- | not a true type, but merely a notational convenience for creating
936+-- unique identifier columns with type `PGint2`
937+serial2, smallserial
938+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint2)
939+serial2 = UnsafeColumnTypeExpression "serial2"
940+smallserial = UnsafeColumnTypeExpression "smallserial"
941+-- | not a true type, but merely a notational convenience for creating
942+-- unique identifier columns with type `PGint4`
943+serial4, serial
944+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint4)
945+serial4 = UnsafeColumnTypeExpression "serial4"
946+serial = UnsafeColumnTypeExpression "serial"
947+-- | not a true type, but merely a notational convenience for creating
948+-- unique identifier columns with type `PGint8`
949+serial8, bigserial
950+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint8)
951+serial8 = UnsafeColumnTypeExpression "serial8"
952+bigserial = UnsafeColumnTypeExpression "bigserial"
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Function.hsdeleted−238
@@ -1,238 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Function
3−Description: Create and drop function and operator definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create and drop function and operator definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Function
33− ( createFunction
34− , createOrReplaceFunction
35− , createSetFunction
36− , createOrReplaceSetFunction
37− , createBinaryOp
38− , createLeftOp
39− , createRightOp
40− , dropFunction
41− , dropFunctionIfExists
42− , dropOperator
43− , dropOperatorIfExists
44− , FunctionDefinition(..)
45− , languageSqlExpr
46− , languageSqlQuery
47− ) where
48−
49−import Control.DeepSeq
50−import Data.ByteString
51−import GHC.TypeLits
52−
53−import qualified Generics.SOP as SOP
54−import qualified GHC.Generics as GHC
55−
56−import Squeal.PostgreSQL.Alias
57−import Squeal.PostgreSQL.Definition
58−import Squeal.PostgreSQL.Expression
59−import Squeal.PostgreSQL.Expression.Type
60−import Squeal.PostgreSQL.List
61−import Squeal.PostgreSQL.Query
62−import Squeal.PostgreSQL.Render
63−import Squeal.PostgreSQL.Schema
64−
65−-- $setup
66−-- >>> import Squeal.PostgreSQL
67−
68−createFunction
69− :: ( Has sch schemas schema
70− , KnownSymbol fun
71− , SOP.SListI args )
72− => QualifiedAlias sch fun
73− -> NP (TypeExpression schemas) args
74− -> TypeExpression schemas ret
75− -> FunctionDefinition schemas args ('Returns ret)
76− -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'Returns ret)) schema) schemas)
77−createFunction fun args ret fundef = UnsafeDefinition $
78− "CREATE" <+> "FUNCTION" <+> renderSQL fun
79− <+> parenthesized (renderCommaSeparated renderSQL args)
80− <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"
81−
82−createOrReplaceFunction
83− :: ( Has sch schemas schema
84− , KnownSymbol fun
85− , SOP.SListI args )
86− => QualifiedAlias sch fun
87− -> NP (TypeExpression schemas) args
88− -> TypeExpression schemas ret
89− -> FunctionDefinition schemas args ('Returns ret)
90− -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'Returns ret)) schema) schemas)
91−createOrReplaceFunction fun args ret fundef = UnsafeDefinition $
92− "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun
93− <+> parenthesized (renderCommaSeparated renderSQL args)
94− <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"
95−
96−languageSqlExpr
97− :: Expression '[] '[] 'Ungrouped schemas args '[] ret
98− -> FunctionDefinition schemas args ('Returns ret)
99−languageSqlExpr expr = UnsafeFunctionDefinition $
100− "language sql as"
101− <+> "$$" <+> renderSQL (values_ (expr `as` #ret)) <+> "$$"
102−
103−languageSqlQuery
104− :: Query '[] '[] schemas args rets
105− -> FunctionDefinition schemas args ('ReturnsTable rets)
106−languageSqlQuery qry = UnsafeFunctionDefinition $
107− "language sql as" <+> "$$" <+> renderSQL qry <+> "$$"
108−
109−createSetFunction
110− :: ( Has sch schemas schema
111− , KnownSymbol fun
112− , SOP.SListI args
113− , SOP.SListI rets )
114− => QualifiedAlias sch fun
115− -> NP (TypeExpression schemas) args
116− -> NP (Aliased (TypeExpression schemas)) rets
117− -> FunctionDefinition schemas args ('ReturnsTable rets)
118− -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)
119−createSetFunction fun args rets fundef = UnsafeDefinition $
120− "CREATE" <+> "FUNCTION" <+> renderSQL fun
121− <+> parenthesized (renderCommaSeparated renderSQL args)
122− <+> "RETURNS" <+> "TABLE"
123− <+> parenthesized (renderCommaSeparated renderRet rets)
124− <+> renderSQL fundef <> ";"
125− where
126− renderRet :: Aliased (TypeExpression s) r -> ByteString
127− renderRet (ty `As` col) = renderSQL col <+> renderSQL ty
128−
129−createOrReplaceSetFunction
130− :: ( Has sch schemas schema
131− , KnownSymbol fun
132− , SOP.SListI args
133− , SOP.SListI rets )
134− => QualifiedAlias sch fun
135− -> NP (TypeExpression schemas) args
136− -> NP (Aliased (TypeExpression schemas)) rets
137− -> FunctionDefinition schemas args ('ReturnsTable rets)
138− -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)
139−createOrReplaceSetFunction fun args rets fundef = UnsafeDefinition $
140− "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun
141− <+> parenthesized (renderCommaSeparated renderSQL args)
142− <+> "RETURNS" <+> "TABLE"
143− <+> parenthesized (renderCommaSeparated renderRet rets)
144− <+> renderSQL fundef <> ";"
145− where
146− renderRet :: Aliased (TypeExpression s) r -> ByteString
147− renderRet (ty `As` col) = renderSQL col <+> renderSQL ty
148−
149−createBinaryOp
150− :: forall op fun sch schemas schema x y z.
151− ( Has sch schemas schema
152− , Has fun schema ('Function ('[x,y] :=> 'Returns z))
153− , KnownSymbol op )
154− => QualifiedAlias sch fun
155− -> TypeExpression schemas x
156− -> TypeExpression schemas y
157− -> Definition schemas
158− (Alter sch (Create op ('Operator ('BinaryOp x y z)) schema) schemas)
159−createBinaryOp fun x y = UnsafeDefinition $
160− "CREATE" <+> "OPERATOR" <+> renderSymbol @op
161− <+> parenthesized (commaSeparated opdef)
162− where
163− opdef =
164− [ "FUNCTION" <+> "=" <+> renderSQL fun
165− , "LEFTARG" <+> "=" <+> renderSQL x
166− , "RIGHTARG" <+> "=" <+> renderSQL y ]
167−
168−createLeftOp
169− :: forall op fun sch schemas schema x y.
170− ( Has sch schemas schema
171− , Has fun schema ('Function ('[x] :=> 'Returns y))
172− , KnownSymbol op )
173− => QualifiedAlias sch fun
174− -> TypeExpression schemas x
175− -> Definition schemas
176− (Alter sch (Create op ('Operator ('LeftOp x y)) schema) schemas)
177−createLeftOp fun x = UnsafeDefinition $
178− "CREATE" <+> "OPERATOR" <+> renderSymbol @op
179− <+> parenthesized (commaSeparated opdef)
180− where
181− opdef =
182− [ "FUNCTION" <+> "=" <+> renderSQL fun
183− , "RIGHTARG" <+> "=" <+> renderSQL x ]
184−
185−createRightOp
186− :: forall op fun sch schemas schema x y.
187− ( Has sch schemas schema
188− , Has fun schema ('Function ('[x] :=> 'Returns y))
189− , KnownSymbol op )
190− => QualifiedAlias sch fun
191− -> TypeExpression schemas x
192− -> Definition schemas
193− (Alter sch (Create op ('Operator ('RightOp x y)) schema) schemas)
194−createRightOp fun x = UnsafeDefinition $
195− "CREATE" <+> "OPERATOR" <+> renderSymbol @op
196− <+> parenthesized (commaSeparated opdef)
197− where
198− opdef =
199− [ "FUNCTION" <+> "=" <+> renderSQL fun
200− , "LEFTARG" <+> "=" <+> renderSQL x ]
201−
202−dropFunction
203− :: (Has sch schemas schema, KnownSymbol fun)
204− => QualifiedAlias sch fun
205− -- ^ name of the user defined function
206− -> Definition schemas (Alter sch (DropSchemum fun 'Function schema) schemas)
207−dropFunction fun = UnsafeDefinition $
208− "DROP" <+> "FUNCTION" <+> renderSQL fun <> ";"
209−
210−dropFunctionIfExists
211− :: (Has sch schemas schema, KnownSymbol fun)
212− => QualifiedAlias sch fun
213− -- ^ name of the user defined function
214− -> Definition schemas (Alter sch (DropSchemumIfExists fun 'Function schema) schemas)
215−dropFunctionIfExists fun = UnsafeDefinition $
216− "DROP FUNCTION IF EXISTS" <+> renderSQL fun <> ";"
217−
218−dropOperator
219− :: (Has sch schemas schema, KnownSymbol op)
220− => QualifiedAlias sch op
221− -- ^ name of the user defined operator
222− -> Definition schemas (Alter sch (DropSchemum op 'Operator schema) schemas)
223−dropOperator op = UnsafeDefinition $
224− "DROP" <+> "OPERATOR" <+> renderSQL op <> ";"
225−
226−dropOperatorIfExists
227− :: (Has sch schemas schema, KnownSymbol op)
228− => QualifiedAlias sch op
229− -- ^ name of the user defined operator
230− -> Definition schemas (Alter sch (DropSchemumIfExists op 'Operator schema) schemas)
231−dropOperatorIfExists op = UnsafeDefinition $
232− "DROP OPERATOR IF EXISTS" <+> renderSQL op <> ";"
233−
234−newtype FunctionDefinition schemas args ret = UnsafeFunctionDefinition
235− { renderFunctionDefinition :: ByteString }
236− deriving (Eq,Show,GHC.Generic,NFData)
237−instance RenderSQL (FunctionDefinition schemas args ret) where
238− renderSQL = renderFunctionDefinition
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Index.hsdeleted−159
@@ -1,159 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Index
3−Description: Create and drop index definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create and drop index definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Index
33− ( createIndex
34− , createIndexIfNotExists
35− , dropIndex
36− , dropIndexIfExists
37− , IndexMethod (..)
38− , btree
39− , hash
40− , gist
41− , spgist
42− , gin
43− , brin
44− ) where
45−
46−import Data.ByteString
47−import GHC.TypeLits
48−
49−import qualified GHC.Generics as GHC
50−
51−import Squeal.PostgreSQL.Alias
52−import Squeal.PostgreSQL.Definition
53−import Squeal.PostgreSQL.Expression.Sort
54−import Squeal.PostgreSQL.Render
55−import Squeal.PostgreSQL.Schema
56−
57−-- $setup
58−-- >>> import Squeal.PostgreSQL
59−
60−{- |
61−>>> :{
62−type Table = '[] :=>
63− '[ "a" ::: 'NoDef :=> 'Null 'PGint4
64− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
65−:}
66−
67−>>> :{
68−let
69− setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table, "ix" ::: 'Index 'Btree])
70− setup =
71− createTable #tab (nullable int `as` #a :* nullable real `as` #b) Nil >>>
72− createIndex #ix #tab btree [#a & AscNullsFirst, #b & AscNullsLast]
73−in printSQL setup
74−:}
75−CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
76−CREATE INDEX "ix" ON "tab" USING btree (("a") ASC NULLS FIRST, ("b") ASC NULLS LAST);
77−-}
78−createIndex
79− :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)
80− => Alias ix
81− -> QualifiedAlias sch tab
82− -> IndexMethod method
83− -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]
84− -> Definition schemas (Alter sch (Create ix ('Index method) schema) schemas)
85−createIndex ix tab method cols = UnsafeDefinition $
86− "CREATE" <+> "INDEX" <+> renderSQL ix <+> "ON" <+> renderSQL tab
87− <+> "USING" <+> renderSQL method
88− <+> parenthesized (commaSeparated (renderIndex <$> cols))
89− <> ";"
90− where
91− renderIndex = \case
92− Asc expression -> parenthesized (renderSQL expression) <+> "ASC"
93− Desc expression -> parenthesized (renderSQL expression) <+> "DESC"
94− AscNullsFirst expression -> parenthesized (renderSQL expression)
95− <+> "ASC NULLS FIRST"
96− DescNullsFirst expression -> parenthesized (renderSQL expression)
97− <+> "DESC NULLS FIRST"
98− AscNullsLast expression -> parenthesized (renderSQL expression)
99− <+> "ASC NULLS LAST"
100− DescNullsLast expression -> parenthesized (renderSQL expression)
101− <+> "DESC NULLS LAST"
102−
103−createIndexIfNotExists
104− :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)
105− => Alias ix
106− -> QualifiedAlias sch tab
107− -> IndexMethod method
108− -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]
109− -> Definition schemas (Alter sch (CreateIfNotExists ix ('Index method) schema) schemas)
110−createIndexIfNotExists ix tab method cols = UnsafeDefinition $
111− "CREATE INDEX IF NOT EXISTS" <+> renderSQL ix <+> "ON" <+> renderSQL tab
112− <+> "USING" <+> renderSQL method
113− <+> parenthesized (commaSeparated (renderIndex <$> cols))
114− <> ";"
115− where
116− renderIndex = \case
117− Asc expression -> parenthesized (renderSQL expression) <+> "ASC"
118− Desc expression -> parenthesized (renderSQL expression) <+> "DESC"
119− AscNullsFirst expression -> parenthesized (renderSQL expression)
120− <+> "ASC NULLS FIRST"
121− DescNullsFirst expression -> parenthesized (renderSQL expression)
122− <+> "DESC NULLS FIRST"
123− AscNullsLast expression -> parenthesized (renderSQL expression)
124− <+> "ASC NULLS LAST"
125− DescNullsLast expression -> parenthesized (renderSQL expression)
126− <+> "DESC NULLS LAST"
127−
128−newtype IndexMethod ty = UnsafeIndexMethod {renderIndexMethod :: ByteString}
129− deriving stock (Eq, Ord, Show, GHC.Generic)
130−instance RenderSQL (IndexMethod ty) where renderSQL = renderIndexMethod
131−btree :: IndexMethod 'Btree
132−btree = UnsafeIndexMethod "btree"
133−hash :: IndexMethod 'Hash
134−hash = UnsafeIndexMethod "hash"
135−gist :: IndexMethod 'Gist
136−gist = UnsafeIndexMethod "gist"
137−spgist :: IndexMethod 'Spgist
138−spgist = UnsafeIndexMethod "spgist"
139−gin :: IndexMethod 'Gin
140−gin = UnsafeIndexMethod "gin"
141−brin :: IndexMethod 'Brin
142−brin = UnsafeIndexMethod "brin"
143−
144−-- |
145−-- >>> printSQL (dropIndex #ix :: Definition (Public '["ix" ::: 'Index 'Btree]) (Public '[]))
146−-- DROP INDEX "ix";
147−dropIndex
148− :: (Has sch schemas schema, KnownSymbol ix)
149− => QualifiedAlias sch ix
150− -- ^ name of the user defined index
151− -> Definition schemas (Alter sch (DropSchemum ix 'Index schema) schemas)
152−dropIndex ix = UnsafeDefinition $ "DROP" <+> "INDEX" <+> renderSQL ix <> ";"
153−
154−dropIndexIfExists
155− :: (Has sch schemas schema, KnownSymbol ix)
156− => QualifiedAlias sch ix
157− -- ^ name of the user defined index
158− -> Definition schemas (Alter sch (DropSchemumIfExists ix 'Index schema) schemas)
159−dropIndexIfExists ix = UnsafeDefinition $ "DROP INDEX IF EXISTS" <+> renderSQL ix <> ";"
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Schema.hsdeleted−96
@@ -1,96 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Schema
3−Description: Create and drop schema definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create and drop schema definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Schema
33− ( createSchema
34− , createSchemaIfNotExists
35− , dropSchema
36− , dropSchemaIfExists
37− ) where
38−
39−import GHC.TypeLits
40−
41−import Squeal.PostgreSQL.Alias
42−import Squeal.PostgreSQL.Definition
43−import Squeal.PostgreSQL.Render
44−import Squeal.PostgreSQL.Schema
45−
46−-- $setup
47−-- >>> import Squeal.PostgreSQL
48−
49−{- |
50−`createSchema` enters a new schema into the current database.
51−The schema name must be distinct from the name of any existing schema
52−in the current database.
53−
54−A schema is essentially a namespace: it contains named objects
55−(tables, data types, functions, and operators) whose names
56−can duplicate those of other objects existing in other schemas.
57−Named objects are accessed by `QualifiedAlias`es with the schema
58−name as a prefix.
59−-}
60−createSchema
61− :: KnownSymbol sch
62− => Alias sch
63− -> Definition schemas (Create sch '[] schemas)
64−createSchema sch = UnsafeDefinition $
65− "CREATE" <+> "SCHEMA" <+> renderSQL sch <> ";"
66−
67−{- | Idempotent version of `createSchema`. -}
68−createSchemaIfNotExists
69− :: (KnownSymbol sch, Has sch schemas schema)
70− => Alias sch
71− -> Definition schemas (CreateIfNotExists sch '[] schemas)
72−createSchemaIfNotExists sch = UnsafeDefinition $
73− "CREATE" <+> "SCHEMA" <+> "IF" <+> "NOT" <+> "EXISTS"
74− <+> renderSQL sch <> ";"
75−
76−-- | >>> :{
77−-- let
78−-- definition :: Definition '["muh_schema" ::: schema, "public" ::: public] '["public" ::: public]
79−-- definition = dropSchema #muh_schema
80−-- :}
81−--
82−-- >>> printSQL definition
83−-- DROP SCHEMA "muh_schema";
84−dropSchema
85− :: KnownSymbol sch
86− => Alias sch
87− -- ^ user defined schema
88− -> Definition schemas (Drop sch schemas)
89−dropSchema sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"
90−
91−dropSchemaIfExists
92− :: KnownSymbol sch
93− => Alias sch
94− -- ^ user defined schema
95− -> Definition schemas (DropIfExists sch schemas)
96−dropSchemaIfExists sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table.hsdeleted−500
@@ -1,500 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Table
3−Description: Create, drop and alter table definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create, drop and alter table definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Table
33− ( createTable
34− , createTableIfNotExists
35− , dropTable
36− , dropTableIfExists
37− , alterTable
38− , alterTableIfExists
39− , alterTableRename
40− , alterTableIfExistsRename
41− , AlterTable (..)
42− , addConstraint
43− , dropConstraint
44− , AddColumn (..)
45− , dropColumn
46− , renameColumn
47− , alterColumn
48− , AlterColumn (..)
49− , setDefault
50− , dropDefault
51− , setNotNull
52− , dropNotNull
53− , alterType
54− ) where
55−
56−import Control.DeepSeq
57−import Data.ByteString
58−import GHC.TypeLits
59−
60−import qualified Generics.SOP as SOP
61−import qualified GHC.Generics as GHC
62−
63−import Squeal.PostgreSQL.Alias
64−import Squeal.PostgreSQL.Definition
65−import Squeal.PostgreSQL.Definition.Table.Constraint
66−import Squeal.PostgreSQL.Expression
67−import Squeal.PostgreSQL.Expression.Type
68−import Squeal.PostgreSQL.List
69−import Squeal.PostgreSQL.Render
70−import Squeal.PostgreSQL.Schema
71−
72−-- $setup
73−-- >>> import Squeal.PostgreSQL
74−
75−{- | `createTable` adds a table to the schema.
76−
77−>>> :set -XOverloadedLabels
78−>>> :{
79−type Table = '[] :=>
80− '[ "a" ::: 'NoDef :=> 'Null 'PGint4
81− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
82−:}
83−
84−>>> :{
85−let
86− setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table])
87− setup = createTable #tab
88− (nullable int `as` #a :* nullable real `as` #b) Nil
89−in printSQL setup
90−:}
91−CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
92−-}
93−createTable
94− :: ( KnownSymbol sch
95− , KnownSymbol tab
96− , columns ~ (col ': cols)
97− , SOP.SListI columns
98− , SOP.SListI constraints
99− , Has sch schemas0 schema0
100− , schemas1 ~ Alter sch (Create tab ('Table (constraints :=> columns)) schema0) schemas0 )
101− => QualifiedAlias sch tab -- ^ the name of the table to add
102− -> NP (Aliased (ColumnTypeExpression schemas0)) columns
103− -- ^ the names and datatype of each column
104− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
105− -- ^ constraints that must hold for the table
106− -> Definition schemas0 schemas1
107−createTable tab columns constraints = UnsafeDefinition $
108− "CREATE TABLE" <+> renderCreation tab columns constraints
109−
110−{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.
111−Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.
112−`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in
113−the `Category` of `Definition`s.
114−
115−>>> :set -XOverloadedLabels -XTypeApplications
116−>>> :{
117−type Table = '[] :=>
118− '[ "a" ::: 'NoDef :=> 'Null 'PGint4
119− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
120−:}
121−
122−>>> type Schemas = Public '["tab" ::: 'Table Table]
123−
124−>>> :{
125−let
126− setup :: Definition Schemas Schemas
127− setup = createTableIfNotExists #tab
128− (nullable int `as` #a :* nullable real `as` #b) Nil
129−in printSQL setup
130−:}
131−CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);
132−-}
133−createTableIfNotExists
134− :: ( KnownSymbol sch
135− , KnownSymbol tab
136− , columns ~ (col ': cols)
137− , SOP.SListI columns
138− , SOP.SListI constraints
139− , Has sch schemas0 schema0
140− , schemas1 ~ Alter sch (CreateIfNotExists tab ('Table (constraints :=> columns)) schema0) schemas0 )
141− => QualifiedAlias sch tab -- ^ the name of the table to add
142− -> NP (Aliased (ColumnTypeExpression schemas0)) columns
143− -- ^ the names and datatype of each column
144− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
145− -- ^ constraints that must hold for the table
146− -> Definition schemas0 schemas1
147−createTableIfNotExists tab columns constraints = UnsafeDefinition $
148− "CREATE TABLE IF NOT EXISTS"
149− <+> renderCreation tab columns constraints
150−
151−-- helper function for `createTable` and `createTableIfNotExists`
152−renderCreation
153− :: ( KnownSymbol sch
154− , KnownSymbol tab
155− , SOP.SListI columns
156− , SOP.SListI constraints )
157− => QualifiedAlias sch tab -- ^ the name of the table to add
158− -> NP (Aliased (ColumnTypeExpression schemas0)) columns
159− -- ^ the names and datatype of each column
160− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
161− -- ^ constraints that must hold for the table
162− -> ByteString
163−renderCreation tab columns constraints = renderSQL tab
164− <+> parenthesized
165− ( renderCommaSeparated renderColumnDef columns
166− <> ( case constraints of
167− Nil -> ""
168− _ -> ", " <>
169− renderCommaSeparated renderConstraint constraints ) )
170− <> ";"
171− where
172− renderColumnDef :: Aliased (ColumnTypeExpression schemas) x -> ByteString
173− renderColumnDef (ty `As` column) =
174− renderSQL column <+> renderColumnTypeExpression ty
175− renderConstraint
176− :: Aliased (TableConstraintExpression sch tab schemas) constraint
177− -> ByteString
178− renderConstraint (constraint `As` alias) =
179− "CONSTRAINT" <+> renderSQL alias <+> renderSQL constraint
180−
181−-- | `dropTable` removes a table from the schema.
182−--
183−-- >>> :{
184−-- let
185−-- definition :: Definition '["public" ::: '["muh_table" ::: 'Table t]] (Public '[])
186−-- definition = dropTable #muh_table
187−-- :}
188−--
189−-- >>> printSQL definition
190−-- DROP TABLE "muh_table";
191−dropTable
192− :: ( Has sch schemas schema
193− , KnownSymbol tab )
194− => QualifiedAlias sch tab -- ^ table to remove
195− -> Definition schemas (Alter sch (DropSchemum tab 'Table schema) schemas)
196−dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderSQL tab <> ";"
197−
198−dropTableIfExists
199− :: ( Has sch schemas schema
200− , KnownSymbol tab)
201− => QualifiedAlias sch tab -- ^ table to remove
202− -> Definition schemas (Alter sch (DropSchemumIfExists tab 'Table schema) schemas)
203−dropTableIfExists tab = UnsafeDefinition $ "DROP TABLE IF EXISTS" <+> renderSQL tab <> ";"
204−
205−-- | `alterTable` changes the definition of a table from the schema.
206−alterTable
207− :: (Has sch schemas schema, KnownSymbol tab)
208− => QualifiedAlias sch tab -- ^ table to alter
209− -> AlterTable sch tab schemas table -- ^ alteration to perform
210− -> Definition schemas (Alter sch (Alter tab ('Table table) schema) schemas)
211−alterTable tab alteration = UnsafeDefinition $
212− "ALTER TABLE"
213− <+> renderSQL tab
214− <+> renderAlterTable alteration
215− <> ";"
216−
217−-- | `alterTable` changes the definition of a table from the schema.
218−alterTableIfExists
219− :: (Has sch schemas schema, KnownSymbol tab)
220− => QualifiedAlias sch tab -- ^ table to alter
221− -> AlterTable sch tab schemas table -- ^ alteration to perform
222− -> Definition schemas (Alter sch (AlterIfExists tab ('Table table) schema) schemas)
223−alterTableIfExists tab alteration = UnsafeDefinition $
224− "ALTER TABLE IF EXISTS"
225− <+> renderSQL tab
226− <+> renderAlterTable alteration
227− <> ";"
228−
229−-- | `alterTableRename` changes the name of a table from the schema.
230−--
231−-- >>> printSQL $ alterTableRename #foo #bar
232−-- ALTER TABLE "foo" RENAME TO "bar";
233−alterTableRename
234− :: (KnownSymbol tab0, KnownSymbol tab1)
235− => Alias tab0 -- ^ table to rename
236− -> Alias tab1 -- ^ what to rename it
237− -> Definition schema (Rename tab0 tab1 schema)
238−alterTableRename tab0 tab1 = UnsafeDefinition $
239− "ALTER TABLE" <+> renderSQL tab0
240− <+> "RENAME TO" <+> renderSQL tab1 <> ";"
241−
242−alterTableIfExistsRename
243− :: (KnownSymbol tab0, KnownSymbol tab1)
244− => Alias tab0 -- ^ table to rename
245− -> Alias tab1 -- ^ what to rename it
246− -> Definition schema (RenameIfExists tab0 tab1 schema)
247−alterTableIfExistsRename tab0 tab1 = UnsafeDefinition $
248− "ALTER TABLE IF EXISTS" <+> renderSQL tab0
249− <+> "RENAME TO" <+> renderSQL tab1 <> ";"
250−
251−-- | An `AlterTable` describes the alteration to perform on the columns
252−-- of a table.
253−newtype AlterTable
254− (sch :: Symbol)
255− (tab :: Symbol)
256− (schemas :: SchemasType)
257− (table :: TableType) =
258− UnsafeAlterTable {renderAlterTable :: ByteString}
259− deriving (GHC.Generic,Show,Eq,Ord,NFData)
260−
261−-- | An `addConstraint` adds a table constraint.
262−--
263−-- >>> :{
264−-- let
265−-- definition :: Definition
266−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
267−-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: 'Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
268−-- definition = alterTable #tab (addConstraint #positive (check #col (#col .> 0)))
269−-- in printSQL definition
270−-- :}
271−-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));
272−addConstraint
273− :: ( KnownSymbol alias
274− , Has sch schemas schema
275− , Has tab schema ('Table table0)
276− , table0 ~ (constraints :=> columns)
277− , table1 ~ (Create alias constraint constraints :=> columns) )
278− => Alias alias
279− -> TableConstraintExpression sch tab schemas constraint
280− -- ^ constraint to add
281− -> AlterTable sch tab schemas table1
282−addConstraint alias constraint = UnsafeAlterTable $
283− "ADD" <+> "CONSTRAINT" <+> renderSQL alias
284− <+> renderSQL constraint
285−
286−-- | A `dropConstraint` drops a table constraint.
287−--
288−-- >>> :{
289−-- let
290−-- definition :: Definition
291−-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
292−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
293−-- definition = alterTable #tab (dropConstraint #positive)
294−-- in printSQL definition
295−-- :}
296−-- ALTER TABLE "tab" DROP CONSTRAINT "positive";
297−dropConstraint
298− :: ( KnownSymbol constraint
299− , Has sch schemas schema
300− , Has tab schema ('Table table0)
301− , table0 ~ (constraints :=> columns)
302− , table1 ~ (Drop constraint constraints :=> columns) )
303− => Alias constraint
304− -- ^ constraint to drop
305− -> AlterTable sch tab schemas table1
306−dropConstraint constraint = UnsafeAlterTable $
307− "DROP" <+> "CONSTRAINT" <+> renderSQL constraint
308−
309−-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.
310−class AddColumn ty where
311− -- | `addColumn` adds a new column, initially filled with whatever
312− -- default value is given or with @NULL@.
313− --
314− -- >>> :{
315− -- let
316− -- definition :: Definition
317− -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
318− -- '["public" ::: '["tab" ::: 'Table ('[] :=>
319− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
320− -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]]
321− -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))
322− -- in printSQL definition
323− -- :}
324− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';
325− --
326− -- >>> :{
327− -- let
328− -- definition :: Definition
329− -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
330− -- '["public" ::: '["tab" ::: 'Table ('[] :=>
331− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
332− -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
333− -- definition = alterTable #tab (addColumn #col2 (text & nullable))
334− -- in printSQL definition
335− -- :}
336− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;
337− addColumn
338− :: ( KnownSymbol column
339− , Has sch schemas schema
340− , Has tab schema ('Table table0)
341− , table0 ~ (constraints :=> columns) )
342− => Alias column -- ^ column to add
343− -> ColumnTypeExpression schemas ty -- ^ type of the new column
344− -> AlterTable sch tab schemas (constraints :=> Create column ty columns)
345− addColumn column ty = UnsafeAlterTable $
346− "ADD COLUMN" <+> renderSQL column <+> renderColumnTypeExpression ty
347−instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)
348−instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)
349−
350−-- | A `dropColumn` removes a column. Whatever data was in the column
351−-- disappears. Table constraints involving the column are dropped, too.
352−-- However, if the column is referenced by a foreign key constraint of
353−-- another table, PostgreSQL will not silently drop that constraint.
354−--
355−-- >>> :{
356−-- let
357−-- definition :: Definition
358−-- '["public" ::: '["tab" ::: 'Table ('[] :=>
359−-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
360−-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
361−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
362−-- definition = alterTable #tab (dropColumn #col2)
363−-- in printSQL definition
364−-- :}
365−-- ALTER TABLE "tab" DROP COLUMN "col2";
366−dropColumn
367− :: ( KnownSymbol column
368− , Has sch schemas schema
369− , Has tab schema ('Table table0)
370− , table0 ~ (constraints :=> columns)
371− , table1 ~ (constraints :=> Drop column columns) )
372− => Alias column -- ^ column to remove
373− -> AlterTable sch tab schemas table1
374−dropColumn column = UnsafeAlterTable $
375− "DROP COLUMN" <+> renderSQL column
376−
377−-- | A `renameColumn` renames a column.
378−--
379−-- >>> :{
380−-- let
381−-- definition :: Definition
382−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]]
383−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]]
384−-- definition = alterTable #tab (renameColumn #foo #bar)
385−-- in printSQL definition
386−-- :}
387−-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";
388−renameColumn
389− :: ( KnownSymbol column0
390− , KnownSymbol column1
391− , Has sch schemas schema
392− , Has tab schema ('Table table0)
393− , table0 ~ (constraints :=> columns)
394− , table1 ~ (constraints :=> Rename column0 column1 columns) )
395− => Alias column0 -- ^ column to rename
396− -> Alias column1 -- ^ what to rename the column
397− -> AlterTable sch tab schemas table1
398−renameColumn column0 column1 = UnsafeAlterTable $
399− "RENAME COLUMN" <+> renderSQL column0 <+> "TO" <+> renderSQL column1
400−
401−-- | An `alterColumn` alters a single column.
402−alterColumn
403− :: ( KnownSymbol column
404− , Has sch schemas schema
405− , Has tab schema ('Table table0)
406− , table0 ~ (constraints :=> columns)
407− , Has column columns ty0
408− , table1 ~ (constraints :=> Alter column ty1 columns))
409− => Alias column -- ^ column to alter
410− -> AlterColumn schemas ty0 ty1 -- ^ alteration to perform
411− -> AlterTable sch tab schemas table1
412−alterColumn column alteration = UnsafeAlterTable $
413− "ALTER COLUMN" <+> renderSQL column <+> renderAlterColumn alteration
414−
415−-- | An `AlterColumn` describes the alteration to perform on a single column.
416−newtype AlterColumn (schemas :: SchemasType) (ty0 :: ColumnType) (ty1 :: ColumnType) =
417− UnsafeAlterColumn {renderAlterColumn :: ByteString}
418− deriving (GHC.Generic,Show,Eq,Ord,NFData)
419−
420−-- | A `setDefault` sets a new default for a column. Note that this doesn't
421−-- affect any existing rows in the table, it just changes the default for
422−-- future insert and update commands.
423−--
424−-- >>> :{
425−-- let
426−-- definition :: Definition
427−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
428−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
429−-- definition = alterTable #tab (alterColumn #col (setDefault 5))
430−-- in printSQL definition
431−-- :}
432−-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;
433−setDefault
434− :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty -- ^ default value to set
435− -> AlterColumn schemas (constraint :=> ty) ('Def :=> ty)
436−setDefault expression = UnsafeAlterColumn $
437− "SET DEFAULT" <+> renderExpression expression
438−
439−-- | A `dropDefault` removes any default value for a column.
440−--
441−-- >>> :{
442−-- let
443−-- definition :: Definition
444−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
445−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
446−-- definition = alterTable #tab (alterColumn #col dropDefault)
447−-- in printSQL definition
448−-- :}
449−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;
450−dropDefault :: AlterColumn schemas ('Def :=> ty) ('NoDef :=> ty)
451−dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"
452−
453−-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.
454−-- The constraint will be checked immediately, so the table data must satisfy
455−-- the constraint before it can be added.
456−--
457−-- >>> :{
458−-- let
459−-- definition :: Definition
460−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
461−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
462−-- definition = alterTable #tab (alterColumn #col setNotNull)
463−-- in printSQL definition
464−-- :}
465−-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;
466−setNotNull
467− :: AlterColumn schemas (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)
468−setNotNull = UnsafeAlterColumn $ "SET NOT NULL"
469−
470−-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.
471−--
472−-- >>> :{
473−-- let
474−-- definition :: Definition
475−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
476−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
477−-- definition = alterTable #tab (alterColumn #col dropNotNull)
478−-- in printSQL definition
479−-- :}
480−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;
481−dropNotNull
482− :: AlterColumn schemas (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)
483−dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"
484−
485−-- | An `alterType` converts a column to a different data type.
486−-- This will succeed only if each existing entry in the column can be
487−-- converted to the new type by an implicit cast.
488−--
489−-- >>> :{
490−-- let
491−-- definition :: Definition
492−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
493−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]]
494−-- definition =
495−-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))
496−-- in printSQL definition
497−-- :}
498−-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;
499−alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty
500−alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table/Constraint.hsdeleted−339
@@ -1,339 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Table.Constraint
3−Description: Table constraint expressions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Table constraint expressions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Table.Constraint
33− ( TableConstraintExpression (..)
34− , check
35− , unique
36− , primaryKey
37− , foreignKey
38− , ForeignKeyed
39− , OnDeleteClause (..)
40− , OnUpdateClause (..)
41− ) where
42−
43−import Control.DeepSeq
44−import Data.ByteString
45−import GHC.TypeLits
46−
47−import qualified Generics.SOP as SOP
48−import qualified GHC.Generics as GHC
49−
50−import Squeal.PostgreSQL.Alias
51−import Squeal.PostgreSQL.Expression.Logic
52−import Squeal.PostgreSQL.List
53−import Squeal.PostgreSQL.Render
54−import Squeal.PostgreSQL.Schema
55−
56−-- $setup
57−-- >>> import Squeal.PostgreSQL
58−
59−-- | Data types are a way to limit the kind of data that can be stored in a
60−-- table. For many applications, however, the constraint they provide is
61−-- too coarse. For example, a column containing a product price should
62−-- probably only accept positive values. But there is no standard data type
63−-- that accepts only positive numbers. Another issue is that you might want
64−-- to constrain column data with respect to other columns or rows.
65−-- For example, in a table containing product information,
66−-- there should be only one row for each product number.
67−-- `TableConstraint`s give you as much control over the data in your tables
68−-- as you wish. If a user attempts to store data in a column that would
69−-- violate a constraint, an error is raised. This applies
70−-- even if the value came from the default value definition.
71−newtype TableConstraintExpression
72− (sch :: Symbol)
73− (tab :: Symbol)
74− (schemas :: SchemasType)
75− (constraint :: TableConstraint)
76− = UnsafeTableConstraintExpression
77− { renderTableConstraintExpression :: ByteString }
78− deriving (GHC.Generic,Show,Eq,Ord,NFData)
79−instance RenderSQL
80− (TableConstraintExpression sch tab schemas constraint) where
81− renderSQL = renderTableConstraintExpression
82−
83−{-| A `check` constraint is the most generic `TableConstraint` type.
84−It allows you to specify that the value in a certain column must satisfy
85−a Boolean (truth-value) expression.
86−
87−>>> :{
88−type Schema = '[
89− "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[
90− "a" ::: 'NoDef :=> 'NotNull 'PGint4,
91− "b" ::: 'NoDef :=> 'NotNull 'PGint4
92− ])]
93−:}
94−
95−>>> :{
96−let
97− definition :: Definition (Public '[]) (Public Schema)
98− definition = createTable #tab
99− ( (int & notNullable) `as` #a :*
100− (int & notNullable) `as` #b )
101− ( check (#a :* #b) (#a .> #b) `as` #inequality )
102−:}
103−
104−>>> printSQL definition
105−CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));
106−-}
107−check
108− :: ( Has sch schemas schema
109− , Has tab schema ('Table table)
110− , HasAll aliases (TableToRow table) subcolumns )
111− => NP Alias aliases
112− -- ^ specify the subcolumns which are getting checked
113− -> (forall t. Condition '[] '[] 'Ungrouped schemas '[] '[t ::: subcolumns])
114− -- ^ a closed `Condition` on those subcolumns
115− -> TableConstraintExpression sch tab schemas ('Check aliases)
116−check _cols condition = UnsafeTableConstraintExpression $
117− "CHECK" <+> parenthesized (renderSQL condition)
118−
119−{-| A `unique` constraint ensure that the data contained in a column,
120−or a group of columns, is unique among all the rows in the table.
121−
122−>>> :{
123−type Schema = '[
124− "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[
125− "a" ::: 'NoDef :=> 'Null 'PGint4,
126− "b" ::: 'NoDef :=> 'Null 'PGint4
127− ])]
128−:}
129−
130−>>> :{
131−let
132− definition :: Definition (Public '[]) (Public Schema)
133− definition = createTable #tab
134− ( (int & nullable) `as` #a :*
135− (int & nullable) `as` #b )
136− ( unique (#a :* #b) `as` #uq_a_b )
137−:}
138−
139−>>> printSQL definition
140−CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));
141−-}
142−unique
143− :: ( Has sch schemas schema
144− , Has tab schema('Table table)
145− , HasAll aliases (TableToRow table) subcolumns )
146− => NP Alias aliases
147− -- ^ specify subcolumns which together are unique for each row
148− -> TableConstraintExpression sch tab schemas ('Unique aliases)
149−unique columns = UnsafeTableConstraintExpression $
150− "UNIQUE" <+> parenthesized (renderSQL columns)
151−
152−{-| A `primaryKey` constraint indicates that a column, or group of columns,
153−can be used as a unique identifier for rows in the table.
154−This requires that the values be both unique and not null.
155−
156−>>> :{
157−type Schema = '[
158− "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[
159− "id" ::: 'Def :=> 'NotNull 'PGint4,
160− "name" ::: 'NoDef :=> 'NotNull 'PGtext
161− ])]
162−:}
163−
164−>>> :{
165−let
166− definition :: Definition (Public '[]) (Public Schema)
167− definition = createTable #tab
168− ( serial `as` #id :*
169− (text & notNullable) `as` #name )
170− ( primaryKey #id `as` #pk_id )
171−:}
172−
173−>>> printSQL definition
174−CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));
175−-}
176−primaryKey
177− :: ( Has sch schemas schema
178− , Has tab schema ('Table table)
179− , HasAll aliases (TableToColumns table) subcolumns
180− , AllNotNull subcolumns )
181− => NP Alias aliases
182− -- ^ specify the subcolumns which together form a primary key.
183− -> TableConstraintExpression sch tab schemas ('PrimaryKey aliases)
184−primaryKey columns = UnsafeTableConstraintExpression $
185− "PRIMARY KEY" <+> parenthesized (renderSQL columns)
186−
187−{-| A `foreignKey` specifies that the values in a column
188−(or a group of columns) must match the values appearing in some row of
189−another table. We say this maintains the referential integrity
190−between two related tables.
191−
192−>>> :{
193−type Schema =
194− '[ "users" ::: 'Table (
195− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
196− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
197− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
198− ])
199− , "emails" ::: 'Table (
200− '[ "pk_emails" ::: 'PrimaryKey '["id"]
201− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
202− ] :=>
203− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
204− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
205− , "email" ::: 'NoDef :=> 'Null 'PGtext
206− ])
207− ]
208−:}
209−
210−>>> :{
211−let
212− setup :: Definition (Public '[]) (Public Schema)
213− setup =
214− createTable #users
215− ( serial `as` #id :*
216− (text & notNullable) `as` #name )
217− ( primaryKey #id `as` #pk_users ) >>>
218− createTable #emails
219− ( serial `as` #id :*
220− (int & notNullable) `as` #user_id :*
221− (text & nullable) `as` #email )
222− ( primaryKey #id `as` #pk_emails :*
223− foreignKey #user_id #users #id
224− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
225−in printSQL setup
226−:}
227−CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
228−CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
229−
230−A `foreignKey` can even be a table self-reference.
231−
232−>>> :{
233−type Schema =
234− '[ "employees" ::: 'Table (
235− '[ "employees_pk" ::: 'PrimaryKey '["id"]
236− , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]
237− ] :=>
238− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
239− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
240− , "employer_id" ::: 'NoDef :=> 'Null 'PGint4
241− ])
242− ]
243−:}
244−
245−>>> :{
246−let
247− setup :: Definition (Public '[]) (Public Schema)
248− setup =
249− createTable #employees
250− ( serial `as` #id :*
251− (text & notNullable) `as` #name :*
252− (integer & nullable) `as` #employer_id )
253− ( primaryKey #id `as` #employees_pk :*
254− foreignKey #employer_id #employees #id
255− OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )
256−in printSQL setup
257−:}
258−CREATE TABLE "employees" ("id" serial, "name" text NOT NULL, "employer_id" integer NULL, CONSTRAINT "employees_pk" PRIMARY KEY ("id"), CONSTRAINT "employees_employer_fk" FOREIGN KEY ("employer_id") REFERENCES "employees" ("id") ON DELETE CASCADE ON UPDATE CASCADE);
259−-}
260−foreignKey
261− :: (ForeignKeyed schemas sch schema child parent
262− table reftable
263− columns refcolumns
264− constraints cols
265− reftys tys )
266− => NP Alias columns
267− -- ^ column or columns in the table
268− -> Alias parent
269− -- ^ reference table
270− -> NP Alias refcolumns
271− -- ^ reference column or columns in the reference table
272− -> OnDeleteClause
273− -- ^ what to do when reference is deleted
274− -> OnUpdateClause
275− -- ^ what to do when reference is updated
276− -> TableConstraintExpression sch child schemas
277− ('ForeignKey columns parent refcolumns)
278−foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $
279− "FOREIGN KEY" <+> parenthesized (renderSQL keys)
280− <+> "REFERENCES" <+> renderSQL parent
281− <+> parenthesized (renderSQL refs)
282− <+> renderSQL ondel
283− <+> renderSQL onupd
284−
285−-- | A constraint synonym between types involved in a foreign key constraint.
286−type ForeignKeyed schemas
287− sch
288− schema
289− child parent
290− table reftable
291− columns refcolumns
292− constraints cols
293− reftys tys =
294− ( Has sch schemas schema
295− , Has child schema ('Table table)
296− , Has parent schema ('Table reftable)
297− , HasAll columns (TableToColumns table) tys
298− , reftable ~ (constraints :=> cols)
299− , HasAll refcolumns cols reftys
300− , SOP.AllZip SamePGType tys reftys
301− , Uniquely refcolumns constraints )
302−
303−-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.
304−data OnDeleteClause
305− = OnDeleteNoAction
306− -- ^ if any referencing rows still exist when the constraint is checked,
307− -- an error is raised
308− | OnDeleteRestrict -- ^ prevents deletion of a referenced row
309− | OnDeleteCascade
310− -- ^ specifies that when a referenced row is deleted,
311− -- row(s) referencing it should be automatically deleted as well
312− deriving (GHC.Generic,Show,Eq,Ord)
313−instance NFData OnDeleteClause
314−-- | Render `OnDeleteClause`.
315−instance RenderSQL OnDeleteClause where
316− renderSQL = \case
317− OnDeleteNoAction -> "ON DELETE NO ACTION"
318− OnDeleteRestrict -> "ON DELETE RESTRICT"
319− OnDeleteCascade -> "ON DELETE CASCADE"
320−
321−-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked
322−-- when a referenced column is changed (updated).
323−data OnUpdateClause
324− = OnUpdateNoAction
325− -- ^ if any referencing rows has not changed when the constraint is checked,
326− -- an error is raised
327− | OnUpdateRestrict -- ^ prevents update of a referenced row
328− | OnUpdateCascade
329− -- ^ the updated values of the referenced column(s) should be copied
330− -- into the referencing row(s)
331− deriving (GHC.Generic,Show,Eq,Ord)
332−instance NFData OnUpdateClause
333−
334−-- | Render `OnUpdateClause`.
335−instance RenderSQL OnUpdateClause where
336− renderSQL = \case
337− OnUpdateNoAction -> "ON UPDATE NO ACTION"
338− OnUpdateRestrict -> "ON UPDATE RESTRICT"
339− OnUpdateCascade -> "ON UPDATE CASCADE"
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Type.hsdeleted−229
@@ -1,229 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.Type
3−Description: Create and drop type definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create and drop type definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.Type
33− ( createTypeEnum
34− , createTypeEnumFrom
35− , createTypeComposite
36− , createTypeCompositeFrom
37− , createTypeRange
38− , createDomain
39− , dropType
40− , dropTypeIfExists
41− ) where
42−
43−import Data.ByteString
44−import Data.Monoid
45−import GHC.TypeLits
46−import Prelude hiding ((.), id)
47−
48−import qualified Generics.SOP as SOP
49−
50−import Squeal.PostgreSQL.Alias
51−import Squeal.PostgreSQL.Expression.Logic
52−import Squeal.PostgreSQL.Expression.Type
53−import Squeal.PostgreSQL.Definition
54−import Squeal.PostgreSQL.List
55−import Squeal.PostgreSQL.PG
56−import Squeal.PostgreSQL.Render
57−import Squeal.PostgreSQL.Schema
58−
59−-- $setup
60−-- >>> import Squeal.PostgreSQL
61−-- >>> import qualified GHC.Generics as GHC
62−-- >>> import qualified Generics.SOP as SOP
63−
64−-- | Enumerated types are created using the `createTypeEnum` command, for example
65−--
66−-- >>> printSQL $ (createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy") :: Definition (Public '[]) '["public" ::: '["mood" ::: 'Typedef ('PGenum '["sad","ok","happy"])]])
67−-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');
68−createTypeEnum
69− :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)
70− => QualifiedAlias sch enum
71− -- ^ name of the user defined enumerated type
72− -> NP PGlabel labels
73− -- ^ labels of the enumerated type
74− -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)
75−createTypeEnum enum labels = UnsafeDefinition $
76− "CREATE" <+> "TYPE" <+> renderSQL enum <+> "AS" <+> "ENUM" <+>
77− parenthesized (renderSQL labels) <> ";"
78−
79−-- | Enumerated types can also be generated from a Haskell type, for example
80−--
81−-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
82−-- >>> instance SOP.Generic Schwarma
83−-- >>> instance SOP.HasDatatypeInfo Schwarma
84−-- >>> :{
85−-- let
86−-- createSchwarma :: Definition (Public '[]) '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]]
87−-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma
88−-- in
89−-- printSQL createSchwarma
90−-- :}
91−-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');
92−createTypeEnumFrom
93− :: forall hask sch enum schemas schema.
94− ( SOP.Generic hask
95− , SOP.All KnownSymbol (LabelsPG hask)
96− , KnownSymbol enum
97− , Has sch schemas schema )
98− => QualifiedAlias sch enum
99− -- ^ name of the user defined enumerated type
100− -> Definition schemas (Alter sch (Create enum ('Typedef (PG (Enumerated hask))) schema) schemas)
101−createTypeEnumFrom enum = createTypeEnum enum
102− (SOP.hpure label :: NP PGlabel (LabelsPG hask))
103−
104−{- | `createTypeComposite` creates a composite type. The composite type is
105−specified by a list of attribute names and data types.
106−
107−>>> :{
108−type PGcomplex = 'PGcomposite
109− '[ "real" ::: 'NotNull 'PGfloat8
110− , "imaginary" ::: 'NotNull 'PGfloat8 ]
111−:}
112−
113−>>> :{
114−let
115− setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]
116− setup = createTypeComposite #complex
117− (float8 `as` #real :* float8 `as` #imaginary)
118−in printSQL setup
119−:}
120−CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
121−-}
122−createTypeComposite
123− :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)
124− => QualifiedAlias sch ty
125− -- ^ name of the user defined composite type
126− -> NP (Aliased (TypeExpression schemas)) fields
127− -- ^ list of attribute names and data types
128− -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)
129−createTypeComposite ty fields = UnsafeDefinition $
130− "CREATE" <+> "TYPE" <+> renderSQL ty <+> "AS" <+> parenthesized
131− (renderCommaSeparated renderField fields) <> ";"
132− where
133− renderField :: Aliased (TypeExpression schemas) x -> ByteString
134− renderField (typ `As` alias) =
135− renderSQL alias <+> renderSQL typ
136−
137−-- | Composite types can also be generated from a Haskell type, for example
138−--
139−-- >>> data Complex = Complex {real :: Double, imaginary :: Double} deriving GHC.Generic
140−-- >>> instance SOP.Generic Complex
141−-- >>> instance SOP.HasDatatypeInfo Complex
142−-- >>> type Schema = '["complex" ::: 'Typedef (PG (Composite Complex))]
143−-- >>> :{
144−-- let
145−-- createComplex :: Definition (Public '[]) (Public Schema)
146−-- createComplex = createTypeCompositeFrom @Complex #complex
147−-- in
148−-- printSQL createComplex
149−-- :}
150−-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
151−createTypeCompositeFrom
152− :: forall hask sch ty schemas schema.
153− ( SOP.All (FieldTyped schemas) (RowPG hask)
154− , KnownSymbol ty
155− , Has sch schemas schema )
156− => QualifiedAlias sch ty
157− -- ^ name of the user defined composite type
158− -> Definition schemas (Alter sch (Create ty ( 'Typedef (PG (Composite hask))) schema) schemas)
159−createTypeCompositeFrom ty = createTypeComposite ty
160− (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype
161− :: NP (Aliased (TypeExpression schemas)) (RowPG hask))
162−
163−{-|
164−`createDomain` creates a new domain. A domain is essentially a data type
165−with constraints (restrictions on the allowed set of values).
166−
167−Domains are useful for abstracting common constraints on fields
168−into a single location for maintenance. For example, several tables might
169−contain email address columns, all requiring the same `check` constraint
170−to verify the address syntax. Define a domain rather than setting up
171−each table's constraint individually.
172−
173−>>> :{
174−let
175− createPositive :: Definition (Public '[]) (Public '["positive" ::: 'Typedef 'PGfloat4])
176− createPositive = createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
177−in printSQL createPositive
178−:}
179−CREATE DOMAIN "positive" AS real CHECK ((("value" > 0) AND "value" IS NOT NULL));
180−-}
181−createDomain
182− :: (Has sch schemas schema, KnownSymbol dom)
183− => QualifiedAlias sch dom
184− -> (forall null. TypeExpression schemas (null ty))
185− -> (forall tab. Condition '[] '[] 'Ungrouped schemas '[] '[tab ::: '["value" ::: 'Null ty]])
186− -> Definition schemas (Alter sch (Create dom ('Typedef ty) schema) schemas)
187−createDomain dom ty condition =
188− UnsafeDefinition $ "CREATE DOMAIN" <+> renderSQL dom
189− <+> "AS" <+> renderTypeExpression ty
190− <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"
191−
192−{- |
193−>>> :{
194−let
195− createSmallIntRange :: Definition (Public '[]) (Public '["int2range" ::: 'Typedef ('PGrange 'PGint2)])
196− createSmallIntRange = createTypeRange #int2range int2
197−in printSQL createSmallIntRange
198−:}
199−CREATE TYPE "int2range" AS RANGE (subtype = int2);
200−-}
201−createTypeRange
202− :: (Has sch schemas schema, KnownSymbol range)
203− => QualifiedAlias sch range
204− -> (forall null. TypeExpression schemas (null ty))
205− -> Definition schemas (Alter sch (Create range ('Typedef ('PGrange ty)) schema) schemas)
206−createTypeRange range ty = UnsafeDefinition $
207− "CREATE" <+> "TYPE" <+> renderSQL range <+> "AS" <+> "RANGE" <+>
208− parenthesized ("subtype" <+> "=" <+> renderTypeExpression ty) <> ";"
209−
210−-- | Drop a type.
211−--
212−-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
213−-- >>> instance SOP.Generic Schwarma
214−-- >>> instance SOP.HasDatatypeInfo Schwarma
215−-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))
216−-- DROP TYPE "schwarma";
217−dropType
218− :: (Has sch schemas schema, KnownSymbol td)
219− => QualifiedAlias sch td
220− -- ^ name of the user defined type
221− -> Definition schemas (Alter sch (DropSchemum td 'Typedef schema) schemas)
222−dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"
223−
224−dropTypeIfExists
225− :: (Has sch schemas schema, KnownSymbol td)
226− => QualifiedAlias sch td
227− -- ^ name of the user defined type
228− -> Definition schemas (Alter sch (DropSchemumIfExists td 'Typedef schema) schemas)
229−dropTypeIfExists tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"
squeal-postgresql/src/Squeal/PostgreSQL/Definition/View.hsdeleted−104
@@ -1,104 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Definition.View
3−Description: Create and drop view definitions
4−Copyright: (c) Eitan Chatav, 2017
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Create and drop view definitions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DerivingStrategies
17− , FlexibleContexts
18− , FlexibleInstances
19− , GADTs
20− , LambdaCase
21− , MultiParamTypeClasses
22− , OverloadedLabels
23− , OverloadedStrings
24− , RankNTypes
25− , ScopedTypeVariables
26− , TypeApplications
27− , TypeInType
28− , TypeOperators
29− , UndecidableSuperClasses
30−#-}
31−
32−module Squeal.PostgreSQL.Definition.View
33− ( createView
34− , createOrReplaceView
35− , dropView
36− , dropViewIfExists
37− ) where
38−
39−import GHC.TypeLits
40−
41−import Squeal.PostgreSQL.Alias
42−import Squeal.PostgreSQL.Definition
43−import Squeal.PostgreSQL.Query
44−import Squeal.PostgreSQL.Render
45−import Squeal.PostgreSQL.Schema
46−
47−-- $setup
48−-- >>> import Squeal.PostgreSQL
49−
50−{- | Create a view.
51−>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]
52−>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]
53−>>> :{
54−let
55− definition :: Definition
56− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]
57− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc" ::: 'View BC]]
58− definition =
59− createView #bc (select_ (#b :* #c) (from (table #abc)))
60−in printSQL definition
61−:}
62−CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";
63−-}
64−createView
65− :: (Has sch schemas schema, KnownSymbol vw)
66− => QualifiedAlias sch vw -- ^ the name of the view to add
67− -> Query '[] '[] schemas '[] view -- ^ query
68− -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)
69−createView alias query = UnsafeDefinition $
70− "CREATE" <+> "VIEW" <+> renderSQL alias <+> "AS"
71− <+> renderQuery query <> ";"
72−
73−createOrReplaceView
74− :: (Has sch schemas schema, KnownSymbol vw)
75− => QualifiedAlias sch vw -- ^ the name of the view to add
76− -> Query '[] '[] schemas '[] view -- ^ query
77− -> Definition schemas (Alter sch (CreateOrReplace vw ('View view) schema) schemas)
78−createOrReplaceView alias query = UnsafeDefinition $
79− "CREATE OR REPLACE VIEW" <+> renderSQL alias <+> "AS"
80− <+> renderQuery query <> ";"
81−
82−-- | Drop a view.
83−--
84−-- >>> :{
85−-- let
86−-- definition :: Definition
87−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
88−-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]
89−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]
90−-- definition = dropView #bc
91−-- in printSQL definition
92−-- :}
93−-- DROP VIEW "bc";
94−dropView
95− :: (Has sch schemas schema, KnownSymbol vw)
96− => QualifiedAlias sch vw -- ^ view to remove
97− -> Definition schemas (Alter sch (DropSchemum vw 'View schema) schemas)
98−dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderSQL vw <> ";"
99−
100−dropViewIfExists
101− :: (Has sch schemas schema, KnownSymbol vw)
102− => QualifiedAlias sch vw -- ^ view to remove
103− -> Definition schemas (Alter sch (DropIfExists vw schema) schemas)
104−dropViewIfExists vw = UnsafeDefinition $ "DROP VIEW IF EXISTS" <+> renderSQL vw <> ";"
squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+1506−341
@@ -1,13 +1,14 @@
1{-|
1{-|
2−Module: Squeal.PostgreSQL.Expression
2+Module: Squeal.PostgreSQL.Query
3Description: Squeal expressions
3Description: Squeal expressions
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
8Squeal expressions are the atoms used to build statements.
8Squeal expressions are the atoms used to build statements.
9-}
9-}
10
10
11+{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
11{-# LANGUAGE
12{-# LANGUAGE
12 AllowAmbiguousTypes
13 AllowAmbiguousTypes
13 , ConstraintKinds
14 , ConstraintKinds
@@ -15,13 +16,11 @@ Squeal expressions are the atoms used to build statements.
15 , FlexibleContexts
16 , FlexibleContexts
16 , FlexibleInstances
17 , FlexibleInstances
17 , FunctionalDependencies
18 , FunctionalDependencies
18− , GADTs
19 , GeneralizedNewtypeDeriving
19 , GeneralizedNewtypeDeriving
20 , LambdaCase
20 , LambdaCase
21 , MagicHash
21 , MagicHash
22 , OverloadedStrings
22 , OverloadedStrings
23 , ScopedTypeVariables
23 , ScopedTypeVariables
24− , StandaloneDeriving
25 , TypeApplications
24 , TypeApplications
26 , TypeFamilies
25 , TypeFamilies
27 , TypeInType
26 , TypeInType
@@ -32,351 +31,505 @@ Squeal expressions are the atoms used to build statements.
32
31
33module Squeal.PostgreSQL.Expression
32module Squeal.PostgreSQL.Expression
34 ( -- * Expression
33 ( -- * Expression
35− Expression (..)
34+ Expression (UnsafeExpression, renderExpression)
36− , Expr
35+ , HasParameter (parameter)
37− , type (-->)
36+ , param
38− , FunctionDB
37+ -- ** Null
39− , unsafeFunction
38+ , null_
40− , function
39+ , notNull
41− , unsafeLeftOp
40+ , coalesce
42− , leftOp
41+ , fromNull
43− , unsafeRightOp
42+ , isNull
44− , rightOp
43+ , isNotNull
45− , Operator
44+ , matchNull
46− , OperatorDB
45+ , nullIf
46+ -- ** Collections
47+ , array
48+ , row
49+ -- ** Functions
47 , unsafeBinaryOp
50 , unsafeBinaryOp
48− , binaryOp
51+ , unsafeUnaryOp
49− , FunctionVar
52+ , unsafeFunction
50− , unsafeFunctionVar
53+ , unsafeVariadicFunction
51− , type (--->)
54+ , atan2_
52− , FunctionNDB
55+ , cast
53− , unsafeFunctionN
56+ , quot_
54− , functionN
57+ , rem_
55− , PGSubset (..)
58+ , trunc
56− , PGIntersect (..)
59+ , round_
60+ , ceiling_
61+ , greatest
62+ , least
63+ -- ** Conditions
64+ , Condition
65+ , true
66+ , false
67+ , not_
68+ , (.&&)
69+ , (.||)
70+ , caseWhenThenElse
71+ , ifThenElse
72+ , (.==)
73+ , (./=)
74+ , (.>=)
75+ , (.<)
76+ , (.<=)
77+ , (.>)
78+ -- ** Time
79+ , currentDate
80+ , currentTime
81+ , currentTimestamp
82+ , localTime
83+ , localTimestamp
84+ -- ** Text
85+ , lower
86+ , upper
87+ , charLength
88+ , like
89+ -- ** json or jsonb operators
90+ , PGarray
91+ , PGarrayOf
92+ , PGjsonKey
93+ , PGjson_
94+ , PGobjectpairs
95+ , (.->)
96+ , (.->>)
97+ , (.#>)
98+ , (.#>>)
99+ -- *** jsonb only operators
100+ , (.@>)
101+ , (.<@)
102+ , (.?)
103+ , (.?|)
104+ , (.?&)
105+ , (.||.)
106+ , (.-.)
107+ , (#-.)
108+ -- *** Functions
109+ , toJson
110+ , toJsonb
111+ , arrayToJson
112+ , rowToJson
113+ , jsonBuildArray
114+ , jsonbBuildArray
115+ , jsonBuildObject
116+ , jsonbBuildObject
117+ , jsonObject
118+ , jsonbObject
119+ , jsonZipObject
120+ , jsonbZipObject
121+ , jsonArrayLength
122+ , jsonbArrayLength
123+ , jsonEachAsComposite
124+ , jsonbEachAsComposite
125+ , jsonObjectKeys
126+ , jsonbObjectKeys
127+ -- ** Aggregation
128+ , unsafeAggregate, unsafeAggregateDistinct
129+ , sum_, sumDistinct
130+ , PGAvg (avg, avgDistinct)
131+ , bitAnd, bitOr, boolAnd, boolOr
132+ , bitAndDistinct, bitOrDistinct, boolAndDistinct, boolOrDistinct
133+ , countStar
134+ , count, countDistinct
135+ , every, everyDistinct
136+ , max_, maxDistinct, min_, minDistinct
137+ -- * Types
138+ , TypeExpression (UnsafeTypeExpression, renderTypeExpression)
139+ , PGTyped (pgtype)
140+ , bool
141+ , int2
142+ , smallint
143+ , int4
144+ , int
145+ , integer
146+ , int8
147+ , bigint
148+ , numeric
149+ , float4
150+ , real
151+ , float8
152+ , doublePrecision
153+ , text
154+ , char
155+ , character
156+ , varchar
157+ , characterVarying
158+ , bytea
159+ , timestamp
160+ , timestampWithTimeZone
161+ , date
162+ , time
163+ , timeWithTimeZone
164+ , interval
165+ , uuid
166+ , inet
167+ , json
168+ , jsonb
169+ , vararray
170+ , fixarray
57 -- * Re-export
171 -- * Re-export
58 , (&)
172 , (&)
59− , K (..)
173+ , NP ((:*), Nil)
60− , unK
61 ) where
174 ) where
62
175
63import Control.Category
176import Control.Category
64import Control.DeepSeq
177import Control.DeepSeq
65import Data.ByteString (ByteString)
178import Data.ByteString (ByteString)
66import Data.Function ((&))
179import Data.Function ((&))
67−import Data.Semigroup hiding (All)
180+import Data.Semigroup
181+import Data.Ratio
68import Data.String
182import Data.String
69−import Generics.SOP hiding (All, from)
183+import Generics.SOP hiding (from)
184+import GHC.Exts (Constraint)
70import GHC.OverloadedLabels
185import GHC.OverloadedLabels
71import GHC.TypeLits
186import GHC.TypeLits
72−import Numeric
73import Prelude hiding (id, (.))
187import Prelude hiding (id, (.))
74
188
75import qualified GHC.Generics as GHC
189import qualified GHC.Generics as GHC
76
190
77−import Squeal.PostgreSQL.Alias
78−import Squeal.PostgreSQL.List
79import Squeal.PostgreSQL.Render
191import Squeal.PostgreSQL.Render
80import Squeal.PostgreSQL.Schema
192import Squeal.PostgreSQL.Schema
81
193
82−-- $setup
83−-- >>> import Squeal.PostgreSQL
84−
85{-----------------------------------------
194{-----------------------------------------
86column expressions
195column expressions
87-----------------------------------------}
196-----------------------------------------}
88
197
89{- | `Expression`s are used in a variety of contexts,
198{- | `Expression`s are used in a variety of contexts,
90−such as in the target `Squeal.PostgreSQL.Query.List` of the
91−`Squeal.PostgreSQL.Query.select` command,
199+such as in the target list of the `Squeal.PostgreSQL.Query.select` command,
92as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or
200as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or
93`Squeal.PostgreSQL.Manipulation.update`,
201`Squeal.PostgreSQL.Manipulation.update`,
94−or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.
202+or in search `Condition`s in a number of commands.
95
203
96The expression syntax allows the calculation of
204The expression syntax allows the calculation of
97values from primitive expression using arithmetic, logical,
205values from primitive expression using arithmetic, logical,
98and other operations.
206and other operations.
99−
100−The type parameters of `Expression` are
101−
102−* @outer :: @ `FromType`, the @from@ clauses of any outer queries in which
103− the `Expression` is a correlated subquery expression;
104−* @commons :: @ `FromType`, the `Squeal.PostgreSQL.Query.CommonTableExpression`s
105− that are in scope for the `Expression`;
106−* @grp :: @ `Grouping`, the `Grouping` of the @from@ clause which may limit
107− which columns may be referenced by alias;
108−* @schemas :: @ `SchemasType`, the schemas of your database that are in
109− scope for the `Expression`;
110−* @from :: @ `FromType`, the @from@ clause which the `Expression` may use
111− to reference columns by alias;
112−* @ty :: @ `NullityType`, the type of the `Expression`.
113-}
207-}
114newtype Expression
208newtype Expression
115− (outer :: FromType)
209+ (schema :: SchemaType)
116− (commons :: FromType)
210+ (relations :: RelationsType)
117− (grp :: Grouping)
211+ (grouping :: Grouping)
118− (schemas :: SchemasType)
119 (params :: [NullityType])
212 (params :: [NullityType])
120− (from :: FromType)
121 (ty :: NullityType)
213 (ty :: NullityType)
122 = UnsafeExpression { renderExpression :: ByteString }
214 = UnsafeExpression { renderExpression :: ByteString }
123 deriving (GHC.Generic,Show,Eq,Ord,NFData)
215 deriving (GHC.Generic,Show,Eq,Ord,NFData)
216+
124−instance RenderSQL (Expression outer commons grp schemas params from ty) where
217+instance RenderSQL (Expression schema relations grouping params ty) where
125 renderSQL = renderExpression
218 renderSQL = renderExpression
126
219
127−-- | An `Expr` is a closed `Expression`.
220+{- | A `HasParameter` constraint is used to indicate a value that is
128−-- It is a F@RankNType@ but don't be scared.
221+supplied externally to a SQL statement.
129−-- Think of it as an expression which sees no
222+`Squeal.PostgreSQL.PQ.manipulateParams`,
130−-- namespaces, so you can't use parameters
223+`Squeal.PostgreSQL.PQ.queryParams` and
131−-- or alias references. It can be used as
224+`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values
132−-- a simple piece of more complex `Expression`s.
225+separately from the SQL command string, in which case `param`s are used to
133−type Expr x
226+refer to the out-of-line data values.
134− = forall outer commons grp schemas params from
135− . Expression outer commons grp schemas params from x
136− -- ^ cannot reference aliases
137−
138−-- | A @RankNType@ for binary operators.
139−type Operator x1 x2 y
140− = forall outer commons grp schemas params from
141− . Expression outer commons grp schemas params from x1
142− -- ^ left input
143− -> Expression outer commons grp schemas params from x2
144− -- ^ right input
145− -> Expression outer commons grp schemas params from y
146− -- ^ output
147−
148−type OperatorDB schemas x1 x2 y
149− = forall outer commons grp params from
150− . Expression outer commons grp schemas params from x1
151− -- ^ left input
152− -> Expression outer commons grp schemas params from x2
153− -- ^ right input
154− -> Expression outer commons grp schemas params from y
155− -- ^ output
156−
157−-- | A @RankNType@ for functions with a single argument.
158−-- These could be either function calls or unary operators.
159−-- This is a subtype of the usual Haskell function type `Prelude.->`,
160−-- indeed a subcategory as it is closed under the usual
161−-- `Prelude..` and `Prelude.id`.
162−type (-->) x y
163− = forall outer commons grp schemas params from
164− . Expression outer commons grp schemas params from x
165− -- ^ input
166− -> Expression outer commons grp schemas params from y
167− -- ^ output
168−
169−type FunctionDB schemas x y
170− = forall outer commons grp params from
171− . Expression outer commons grp schemas params from x
172− -- ^ input
173− -> Expression outer commons grp schemas params from y
174− -- ^ output
175−
176−{- | A @RankNType@ for functions with a fixed-length list of heterogeneous arguments.
177−Use the `*:` operator to end your argument lists, like so.
178−
179−>>> printSQL (unsafeFunctionN "fun" (true :* false :* localTime *: true))
180−fun(TRUE, FALSE, LOCALTIME, TRUE)
181−-}
182−type (--->) xs y
183− = forall outer commons grp schemas params from
184− . NP (Expression outer commons grp schemas params from) xs
185− -- ^ inputs
186− -> Expression outer commons grp schemas params from y
187− -- ^ output
188−
189−type FunctionNDB schemas xs y
190− = forall outer commons grp params from
191− . NP (Expression outer commons grp schemas params from) xs
192− -- ^ inputs
193− -> Expression outer commons grp schemas params from y
194− -- ^ output
195−
196−{- | A @RankNType@ for functions with a variable-length list of
197−homogeneous arguments and at least 1 more argument.
198-}
227-}
199−type FunctionVar x0 x1 y
228+class KnownNat n => HasParameter
200− = forall outer commons grp schemas params from
229+ (n :: Nat)
201− . [Expression outer commons grp schemas params from x0]
230+ (schema :: SchemaType)
202− -- ^ inputs
231+ (params :: [NullityType])
203− -> Expression outer commons grp schemas params from x1
232+ (ty :: NullityType)
204− -- ^ must have at least 1 input
233+ | n params -> ty where
205− -> Expression outer commons grp schemas params from y
234+ -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.
206− -- ^ output
235+ --
207−
236+ -- >>> let expr = parameter @1 int4 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)
208−{- | >>> printSQL (unsafeFunctionVar "greatest" [true, null_] false)
237+ -- >>> printSQL expr
209−greatest(TRUE, NULL, FALSE)
238+ -- ($1 :: int4)
210−-}
239+ parameter
211−unsafeFunctionVar :: ByteString -> FunctionVar x0 x1 y
240+ :: TypeExpression schema (PGTypeOf ty)
241+ -> Expression schema relations grouping params ty
212−unsafeFunctionVar fun xs x = UnsafeExpression $ fun <> parenthesized
242+ parameter ty = UnsafeExpression $ parenthesized $
213− (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)
243+ "$" <> renderNat (Proxy @n) <+> "::"
214−
244+ <+> renderTypeExpression ty
215−instance (HasUnique tab (Join outer from) row, Has col row ty)
245+instance {-# OVERLAPPING #-} HasParameter 1 schema (ty1:tys) ty1
216− => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where
246+instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) schema params ty)
217− fromLabel = UnsafeExpression $ renderSQL (Alias @col)
247+ => HasParameter n schema (ty' : params) ty
218−instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])
248+
219− => IsLabel col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
249+-- | `param` takes a `Nat` using type application and for basic types,
220− fromLabel = fromLabel @col :* Nil
250+-- infers a `TypeExpression`.
251+--
252+-- >>> let expr = param @1 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)
253+-- >>> printSQL expr
254+-- ($1 :: int4)
255+param
256+ :: forall n schema params relations grouping ty
257+ . (PGTyped schema (PGTypeOf ty), HasParameter n schema params ty)
258+ => Expression schema relations grouping params ty -- ^ param
259+param = parameter @n pgtype
260+
221−instance (HasUnique tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
261+instance (HasUnique relation relations columns, Has column columns ty)
222− => IsLabel col
223− (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
262+ => IsLabel column (Expression schema relations 'Ungrouped params ty) where
224− fromLabel = fromLabel @col `As` Alias
263+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)
225−instance (HasUnique tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
264+instance (HasUnique relation relations columns, Has column columns ty)
226− => IsLabel col
265+ => IsLabel column
227− (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
266+ (Aliased (Expression schema relations 'Ungrouped params) (column ::: ty)) where
228− fromLabel = fromLabel @col :* Nil
267+ fromLabel = fromLabel @column `As` Alias @column
229−
268+instance (HasUnique relation relations columns, Has column columns ty)
230−instance (Has tab (Join outer from) row, Has col row ty)
269+ => IsLabel column
231− => IsQualified tab col (Expression outer commons 'Ungrouped schemas params from ty) where
270+ (NP (Aliased (Expression schema relations 'Ungrouped params)) '[column ::: ty]) where
232− tab ! col = UnsafeExpression $
271+ fromLabel = fromLabel @column :* Nil
233− renderSQL tab <> "." <> renderSQL col
272+
234−instance (Has tab (Join outer from) row, Has col row ty, tys ~ '[ty])
273+instance (Has relation relations columns, Has column columns ty)
235− => IsQualified tab col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
274+ => IsQualified relation column (Expression schema relations 'Ungrouped params ty) where
236− tab ! col = tab ! col :* Nil
275+ relation ! column = UnsafeExpression $
276+ renderAlias relation <> "." <> renderAlias column
237−instance (Has tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
277+instance (Has relation relations columns, Has column columns ty)
238− => IsQualified tab col
278+ => IsQualified relation column
239− (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
279+ (Aliased (Expression schema relations 'Ungrouped params) (column ::: ty)) where
240− tab ! col = tab ! col `As` col
280+ relation ! column = relation ! column `As` column
241−instance (Has tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
281+instance (Has relation relations columns, Has column columns ty)
242− => IsQualified tab col
282+ => IsQualified relation column
243− (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
283+ (NP (Aliased (Expression schema relations 'Ungrouped params)) '[column ::: ty]) where
244− tab ! col = tab ! col :* Nil
284+ relation ! column = relation ! column :* Nil
245
285
246instance
286instance
247− ( HasUnique tab (Join outer from) row
287+ ( HasUnique relation relations columns
248− , Has col row ty
288+ , Has column columns ty
249− , GroupedBy tab col bys
289+ , GroupedBy relation column bys
250− ) => IsLabel col
290+ ) => IsLabel column
251− (Expression outer commons ('Grouped bys) schemas params from ty) where
291+ (Expression schema relations ('Grouped bys) params ty) where
252− fromLabel = UnsafeExpression $ renderSQL (Alias @col)
292+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)
253−instance
254− ( HasUnique tab (Join outer from) row
255− , Has col row ty
256− , GroupedBy tab col bys
257− , tys ~ '[ty]
258− ) => IsLabel col
259− (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where
260− fromLabel = fromLabel @col :* Nil
261instance
293instance
262− ( HasUnique tab (Join outer from) row
294+ ( HasUnique relation relations columns
263− , Has col row ty
295+ , Has column columns ty
264− , GroupedBy tab col bys
296+ , GroupedBy relation column bys
265− , column ~ (col ::: ty)
266− ) => IsLabel col
297+ ) => IsLabel column
267− (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
298+ ( Aliased (Expression schema relations ('Grouped bys) params)
299+ (column ::: ty) ) where
268− fromLabel = fromLabel @col `As` Alias
300+ fromLabel = fromLabel @column `As` Alias @column
269instance
301instance
270− ( HasUnique tab (Join outer from) row
302+ ( HasUnique relation relations columns
271− , Has col row ty
303+ , Has column columns ty
272− , GroupedBy tab col bys
304+ , GroupedBy relation column bys
273− , columns ~ '[col ::: ty]
274− ) => IsLabel col
305+ ) => IsLabel column
275− (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
306+ ( NP (Aliased (Expression schema relations ('Grouped bys) params))
307+ '[column ::: ty] ) where
276− fromLabel = fromLabel @col :* Nil
308+ fromLabel = fromLabel @column :* Nil
277
309
278instance
310instance
279− ( Has tab (Join outer from) row
311+ ( Has relation relations columns
280− , Has col row ty
312+ , Has column columns ty
281− , GroupedBy tab col bys
313+ , GroupedBy relation column bys
282− ) => IsQualified tab col
314+ ) => IsQualified relation column
283− (Expression outer commons ('Grouped bys) schemas params from ty) where
315+ (Expression schema relations ('Grouped bys) params ty) where
284− tab ! col = UnsafeExpression $
316+ relation ! column = UnsafeExpression $
285− renderSQL tab <> "." <> renderSQL col
317+ renderAlias relation <> "." <> renderAlias column
286−instance
287− ( Has tab (Join outer from) row
288− , Has col row ty
289− , GroupedBy tab col bys
290− , tys ~ '[ty]
291− ) => IsQualified tab col
292− (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where
293− tab ! col = tab ! col :* Nil
294instance
318instance
295− ( Has tab (Join outer from) row
319+ ( Has relation relations columns
296− , Has col row ty
320+ , Has column columns ty
297− , GroupedBy tab col bys
321+ , GroupedBy relation column bys
298− , column ~ (col ::: ty)
299− ) => IsQualified tab col
322+ ) => IsQualified relation column
300− (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
323+ (Aliased (Expression schema relations ('Grouped bys) params)
301− tab ! col = tab ! col `As` col
324+ (column ::: ty)) where
325+ relation ! column = relation ! column `As` column
302instance
326instance
303− ( Has tab (Join outer from) row
327+ ( Has relation relations columns
304− , Has col row ty
328+ , Has column columns ty
305− , GroupedBy tab col bys
329+ , GroupedBy relation column bys
306− , columns ~ '[col ::: ty]
307− ) => IsQualified tab col
330+ ) => IsQualified relation column
308− (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
331+ ( NP (Aliased (Expression schema relations ('Grouped bys) params))
309− tab ! col = tab ! col :* Nil
332+ '[column ::: ty]) where
333+ relation ! column = relation ! column :* Nil
334+
335+-- | analagous to `Nothing`
336+--
337+-- >>> printSQL null_
338+-- NULL
339+null_ :: Expression schema rels grouping params ('Null ty)
340+null_ = UnsafeExpression "NULL"
341+
342+-- | analagous to `Just`
343+--
344+-- >>> printSQL $ notNull true
345+-- TRUE
346+notNull
347+ :: Expression schema rels grouping params ('NotNull ty)
348+ -> Expression schema rels grouping params ('Null ty)
349+notNull = UnsafeExpression . renderExpression
350+
351+-- | return the leftmost value which is not NULL
352+--
353+-- >>> printSQL $ coalesce [null_, notNull true] false
354+-- COALESCE(NULL, TRUE, FALSE)
355+coalesce
356+ :: [Expression schema relations grouping params ('Null ty)]
357+ -- ^ @NULL@s may be present
358+ -> Expression schema relations grouping params ('NotNull ty)
359+ -- ^ @NULL@ is absent
360+ -> Expression schema relations grouping params ('NotNull ty)
361+coalesce nullxs notNullx = UnsafeExpression $
362+ "COALESCE" <> parenthesized (commaSeparated
363+ ((renderExpression <$> nullxs) <> [renderExpression notNullx]))
364+
365+-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@
366+--
367+-- >>> printSQL $ fromNull true null_
368+-- COALESCE(NULL, TRUE)
369+fromNull
370+ :: Expression schema relations grouping params ('NotNull ty)
371+ -- ^ what to convert @NULL@ to
372+ -> Expression schema relations grouping params ('Null ty)
373+ -> Expression schema relations grouping params ('NotNull ty)
374+fromNull notNullx nullx = coalesce [nullx] notNullx
375+
376+-- | >>> printSQL $ null_ & isNull
377+-- NULL IS NULL
378+isNull
379+ :: Expression schema relations grouping params ('Null ty)
380+ -- ^ possibly @NULL@
381+ -> Condition schema relations grouping params
382+isNull x = UnsafeExpression $ renderExpression x <+> "IS NULL"
383+
384+-- | >>> printSQL $ null_ & isNotNull
385+-- NULL IS NOT NULL
386+isNotNull
387+ :: Expression schema relations grouping params ('Null ty)
388+ -- ^ possibly @NULL@
389+ -> Condition schema relations grouping params
390+isNotNull x = UnsafeExpression $ renderExpression x <+> "IS NOT NULL"
391+
392+-- | analagous to `maybe` using @IS NULL@
393+--
394+-- >>> printSQL $ matchNull true not_ null_
395+-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END
396+matchNull
397+ :: Expression schema relations grouping params (nullty)
398+ -- ^ what to convert @NULL@ to
399+ -> ( Expression schema relations grouping params ('NotNull ty)
400+ -> Expression schema relations grouping params (nullty) )
401+ -- ^ function to perform when @NULL@ is absent
402+ -> Expression schema relations grouping params ('Null ty)
403+ -> Expression schema relations grouping params (nullty)
404+matchNull y f x = ifThenElse (isNull x) y
405+ (f (UnsafeExpression (renderExpression x)))
406+
407+{-| right inverse to `fromNull`, if its arguments are equal then
408+`nullIf` gives @NULL@.
409+
410+>>> :set -XTypeApplications -XDataKinds
411+>>> let expr = nullIf false (param @1) :: Expression schema rels grp '[ 'NotNull 'PGbool] ('Null 'PGbool)
412+>>> printSQL expr
413+NULL IF (FALSE, ($1 :: bool))
414+-}
415+nullIf
416+ :: Expression schema relations grouping params ('NotNull ty)
417+ -- ^ @NULL@ is absent
418+ -> Expression schema relations grouping params ('NotNull ty)
419+ -- ^ @NULL@ is absent
420+ -> Expression schema relations grouping params ('Null ty)
421+nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized
422+ (renderExpression x <> ", " <> renderExpression y)
423+
424+-- | >>> printSQL $ array [null_, notNull false, notNull true]
425+-- ARRAY[NULL, FALSE, TRUE]
426+array
427+ :: [Expression schema relations grouping params ('Null ty)]
428+ -- ^ array elements
429+ -> Expression schema relations grouping params (nullity ('PGvararray ty))
430+array xs = UnsafeExpression $
431+ "ARRAY[" <> commaSeparated (renderExpression <$> xs) <> "]"
310
432
311instance (KnownSymbol label, label `In` labels) => IsPGlabel label
433instance (KnownSymbol label, label `In` labels) => IsPGlabel label
312− (Expression outer commons grp schemas params from (null ('PGenum labels))) where
434+ (Expression schema relations grouping params (nullity ('PGenum labels))) where
313− label = UnsafeExpression $ renderSQL (PGlabel @label)
435+ label = UnsafeExpression $ renderLabel (PGlabel @label)
436+
437+-- | A row constructor is an expression that builds a row value
438+-- (also called a composite value) using values for its member fields.
439+--
440+-- >>> type Complex = PGcomposite '["real" ::: 'PGfloat8, "imaginary" ::: 'PGfloat8]
441+-- >>> let i = row (0 `As` #real :* 1 `As` #imaginary :* Nil) :: Expression '[] '[] 'Ungrouped '[] ('NotNull Complex)
442+-- >>> printSQL i
443+-- ROW(0, 1)
444+row
445+ :: SListI (Nulls fields)
446+ => NP (Aliased (Expression schema relations grouping params)) (Nulls fields)
447+ -- ^ zero or more expressions for the row field values
448+ -> Expression schema relations grouping params (nullity ('PGcomposite fields))
449+row exprs = UnsafeExpression $ "ROW" <> parenthesized
450+ (renderCommaSeparated (\ (expr `As` _) -> renderExpression expr) exprs)
451+
452+instance Has field fields ty => IsLabel field
453+ ( Expression schema relation grouping params (nullity ('PGcomposite fields))
454+ -> Expression schema relation grouping params ('Null ty) ) where
455+ fromLabel expr = UnsafeExpression $
456+ parenthesized (renderExpression expr) <> "." <>
457+ fromString (symbolVal (Proxy @field))
458+
459+instance Semigroup
460+ (Expression schema relations grouping params (nullity ('PGvararray ty))) where
461+ (<>) = unsafeBinaryOp "||"
462+
463+instance Monoid
464+ (Expression schema relations grouping params (nullity ('PGvararray ty))) where
465+ mempty = array []
466+ mappend = (<>)
467+
468+-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression sch rels grp '[ 'NotNull 'PGtimestamptz] ('NotNull 'PGtimestamptz)
469+-- >>> printSQL expr
470+-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))
471+greatest
472+ :: Expression schema relations grouping params (nullty)
473+ -- ^ needs at least 1 argument
474+ -> [Expression schema relations grouping params (nullty)]
475+ -- ^ or more
476+ -> Expression schema relations grouping params (nullty)
477+greatest x xs = UnsafeExpression $ "GREATEST("
478+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"
479+
480+-- | >>> printSQL $ least currentTimestamp [null_]
481+-- LEAST(CURRENT_TIMESTAMP, NULL)
482+least
483+ :: Expression schema relations grouping params (nullty)
484+ -- ^ needs at least 1 argument
485+ -> [Expression schema relations grouping params (nullty)]
486+ -- ^ or more
487+ -> Expression schema relations grouping params (nullty)
488+least x xs = UnsafeExpression $ "LEAST("
489+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"
314
490
315-- | >>> printSQL $ unsafeBinaryOp "OR" true false
491-- | >>> printSQL $ unsafeBinaryOp "OR" true false
316-- (TRUE OR FALSE)
492-- (TRUE OR FALSE)
317−unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2
493+unsafeBinaryOp
494+ :: ByteString
495+ -- ^ operator
496+ -> Expression schema relations grouping params (ty0)
497+ -> Expression schema relations grouping params (ty1)
498+ -> Expression schema relations grouping params (ty2)
318unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $
499unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $
319− renderSQL x <+> op <+> renderSQL y
500+ renderExpression x <+> op <+> renderExpression y
320−
321−binaryOp
322− :: forall op sch schemas schema x y z.
323− ( Has sch schemas schema
324− , Has op schema ('Operator ('BinaryOp x y z)) )
325− => OperatorDB schemas x y z
326−binaryOp = unsafeBinaryOp $ renderSymbol @op
327
501
328−-- | >>> printSQL $ unsafeLeftOp "NOT" true
502+-- | >>> printSQL $ unsafeUnaryOp "NOT" true
329-- (NOT TRUE)
503-- (NOT TRUE)
504+unsafeUnaryOp
330−unsafeLeftOp :: ByteString -> x --> y
505+ :: ByteString
331−unsafeLeftOp op x = UnsafeExpression $ parenthesized $ op <+> renderSQL x
506+ -- ^ operator
332−
507+ -> Expression schema relations grouping params (ty0)
333−leftOp
508+ -> Expression schema relations grouping params (ty1)
334− :: forall op sch schemas schema x y.
335− ( Has sch schemas schema
336− , Has op schema ('Operator ('LeftOp x y)) )
337− => FunctionDB schemas x y
338−leftOp = unsafeLeftOp $ renderSymbol @op
339−
340−-- | >>> printSQL $ true & unsafeRightOp "IS NOT TRUE"
341−-- (TRUE IS NOT TRUE)
342−unsafeRightOp :: ByteString -> x --> y
343−unsafeRightOp op x = UnsafeExpression $ parenthesized $ renderSQL x <+> op
509+unsafeUnaryOp op x = UnsafeExpression $ parenthesized $
344−
510+ op <+> renderExpression x
345−rightOp
346− :: forall op sch schemas schema x y.
347− ( Has sch schemas schema
348− , Has op schema ('Operator ('RightOp x y)) )
349− => FunctionDB schemas x y
350−rightOp = unsafeRightOp $ renderSymbol @op
351
511
352-- | >>> printSQL $ unsafeFunction "f" true
512-- | >>> printSQL $ unsafeFunction "f" true
353-- f(TRUE)
513-- f(TRUE)
354−unsafeFunction :: ByteString -> x --> y
514+unsafeFunction
515+ :: ByteString
516+ -- ^ function
517+ -> Expression schema relations grouping params (xty)
518+ -> Expression schema relations grouping params (yty)
355unsafeFunction fun x = UnsafeExpression $
519unsafeFunction fun x = UnsafeExpression $
356− fun <> parenthesized (renderSQL x)
520+ fun <> parenthesized (renderExpression x)
357−
521+
358−function
522+unsafeVariadicFunction
359− :: (Has sch schemas schema, Has fun schema ('Function ('[x] :=> 'Returns y)))
523+ :: SListI elems
360− => QualifiedAlias sch fun
361− -> FunctionDB schemas x y
362−function = unsafeFunction . renderSQL
363−
364−-- | >>> printSQL $ unsafeFunctionN "f" (currentTime :* localTimestamp :* false *: literal 'a')
365−-- f(CURRENT_TIME, LOCALTIMESTAMP, FALSE, E'a')
366−unsafeFunctionN :: SListI xs => ByteString -> xs ---> y
524+ => ByteString
525+ -- ^ function
526+ -> NP (Expression schema relations grouping params) elems
527+ -> Expression schema relations grouping params ret
367−unsafeFunctionN fun xs = UnsafeExpression $
528+unsafeVariadicFunction fun x = UnsafeExpression $
368− fun <> parenthesized (renderCommaSeparated renderSQL xs)
529+ fun <> parenthesized (commaSeparated (hcollapse (hmap (K . renderExpression) x)))
369−
530+
370−functionN
371− :: ( Has sch schemas schema
372− , Has fun schema ('Function (xs :=> 'Returns y))
373− , SListI xs )
374− => QualifiedAlias sch fun
375− -> FunctionNDB schemas xs y
376−functionN = unsafeFunctionN . renderSQL
377−
378−instance ty `In` PGNum
531+instance PGNum ty
379− => Num (Expression outer commons grp schemas params from (null ty)) where
532+ => Num (Expression schema relations grouping params (nullity ty)) where
380 (+) = unsafeBinaryOp "+"
533 (+) = unsafeBinaryOp "+"
381 (-) = unsafeBinaryOp "-"
534 (-) = unsafeBinaryOp "-"
382 (*) = unsafeBinaryOp "*"
535 (*) = unsafeBinaryOp "*"
@@ -387,24 +540,19 @@ instance ty `In` PGNum
387 . fromString
540 . fromString
388 . show
541 . show
389
542
390−instance (ty `In` PGNum, ty `In` PGFloating) => Fractional
543+instance (PGNum ty, PGFloating ty) => Fractional
391− (Expression outer commons grp schemas params from (null ty)) where
544+ (Expression schema relations grouping params (nullity ty)) where
392 (/) = unsafeBinaryOp "/"
545 (/) = unsafeBinaryOp "/"
393− fromRational
546+ fromRational x = fromInteger (numerator x) / fromInteger (denominator x)
394− = UnsafeExpression
395− . fromString
396− . ($ "")
397− . showFFloat Nothing
398− . fromRat @Double
399
547
400−instance (ty `In` PGNum, ty `In` PGFloating) => Floating
548+instance (PGNum ty, PGFloating ty) => Floating
401− (Expression outer commons grp schemas params from (null ty)) where
549+ (Expression schema relations grouping params (nullity ty)) where
402 pi = UnsafeExpression "pi()"
550 pi = UnsafeExpression "pi()"
403 exp = unsafeFunction "exp"
551 exp = unsafeFunction "exp"
404 log = unsafeFunction "ln"
552 log = unsafeFunction "ln"
405 sqrt = unsafeFunction "sqrt"
553 sqrt = unsafeFunction "sqrt"
406 b ** x = UnsafeExpression $
554 b ** x = UnsafeExpression $
407− "power(" <> renderSQL b <> ", " <> renderSQL x <> ")"
555+ "power(" <> renderExpression b <> ", " <> renderExpression x <> ")"
408 logBase b y = log y / log b
556 logBase b y = log y / log b
409 sin = unsafeFunction "sin"
557 sin = unsafeFunction "sin"
410 cos = unsafeFunction "cos"
558 cos = unsafeFunction "cos"
@@ -419,54 +567,1071 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating
419 acosh x = log (x + sqrt (x*x - 1))
567 acosh x = log (x + sqrt (x*x - 1))
420 atanh x = log ((1 + x) / (1 - x)) / 2
568 atanh x = log ((1 + x) / (1 - x)) / 2
421
569
422−-- | Contained by operators
570+-- | >>> :{
423−class PGSubset ty where
571+-- let
424− (@>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
572+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
425− (@>) = unsafeBinaryOp "@>"
573+-- expression = atan2_ pi 2
426− (<@) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
574+-- in printSQL expression
427− (<@) = unsafeBinaryOp "<@"
575+-- :}
428−instance PGSubset 'PGjsonb
576+-- atan2(pi(), 2)
429−instance PGSubset 'PGtsquery
577+atan2_
430−instance PGSubset ('PGvararray ty)
578+ :: PGFloating float
431−instance PGSubset ('PGrange ty)
579+ => Expression schema relations grouping params (nullity float)
432−
580+ -- ^ numerator
433−class PGIntersect ty where
581+ -> Expression schema relations grouping params (nullity float)
434− (@&&) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
582+ -- ^ denominator
435− (@&&) = unsafeBinaryOp "&&"
583+ -> Expression schema relations grouping params (nullity float)
436−instance PGIntersect ('PGvararray ty)
584+atan2_ y x = UnsafeExpression $
437−instance PGIntersect ('PGrange ty)
585+ "atan2(" <> renderExpression y <> ", " <> renderExpression x <> ")"
586+
587+-- When a `cast` is applied to an `Expression` of a known type, it
588+-- represents a run-time type conversion. The cast will succeed only if a
589+-- suitable type conversion operation has been defined.
590+--
591+-- | >>> printSQL $ true & cast int4
592+-- (TRUE :: int4)
593+cast
594+ :: TypeExpression schema ty1
595+ -- ^ type to cast as
596+ -> Expression schema relations grouping params (nullity ty0)
597+ -- ^ value to convert
598+ -> Expression schema relations grouping params (nullity ty1)
599+cast ty x = UnsafeExpression $ parenthesized $
600+ renderExpression x <+> "::" <+> renderTypeExpression ty
601+
602+-- | integer division, truncates the result
603+--
604+-- >>> :{
605+-- let
606+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
607+-- expression = 5 `quot_` 2
608+-- in printSQL expression
609+-- :}
610+-- (5 / 2)
611+quot_
612+ :: PGIntegral int
613+ => Expression schema relations grouping params (nullity int)
614+ -- ^ numerator
615+ -> Expression schema relations grouping params (nullity int)
616+ -- ^ denominator
617+ -> Expression schema relations grouping params (nullity int)
618+quot_ = unsafeBinaryOp "/"
619+
620+-- | remainder upon integer division
621+--
622+-- >>> :{
623+-- let
624+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
625+-- expression = 5 `rem_` 2
626+-- in printSQL expression
627+-- :}
628+-- (5 % 2)
629+rem_
630+ :: PGIntegral int
631+ => Expression schema relations grouping params (nullity int)
632+ -- ^ numerator
633+ -> Expression schema relations grouping params (nullity int)
634+ -- ^ denominator
635+ -> Expression schema relations grouping params (nullity int)
636+rem_ = unsafeBinaryOp "%"
637+
638+-- | >>> :{
639+-- let
640+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
641+-- expression = trunc pi
642+-- in printSQL expression
643+-- :}
644+-- trunc(pi())
645+trunc
646+ :: PGFloating frac
647+ => Expression schema relations grouping params (nullity frac)
648+ -- ^ fractional number
649+ -> Expression schema relations grouping params (nullity frac)
650+trunc = unsafeFunction "trunc"
651+
652+-- | >>> :{
653+-- let
654+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
655+-- expression = round_ pi
656+-- in printSQL expression
657+-- :}
658+-- round(pi())
659+round_
660+ :: PGFloating frac
661+ => Expression schema relations grouping params (nullity frac)
662+ -- ^ fractional number
663+ -> Expression schema relations grouping params (nullity frac)
664+round_ = unsafeFunction "round"
665+
666+-- | >>> :{
667+-- let
668+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
669+-- expression = ceiling_ pi
670+-- in printSQL expression
671+-- :}
672+-- ceiling(pi())
673+ceiling_
674+ :: PGFloating frac
675+ => Expression schema relations grouping params (nullity frac)
676+ -- ^ fractional number
677+ -> Expression schema relations grouping params (nullity frac)
678+ceiling_ = unsafeFunction "ceiling"
679+
680+-- | A `Condition` is a boolean valued `Expression`. While SQL allows
681+-- conditions to have @NULL@, Squeal instead chooses to disallow @NULL@,
682+-- forcing one to handle the case of @NULL@ explicitly to produce
683+-- a `Condition`.
684+type Condition schema relations grouping params =
685+ Expression schema relations grouping params ('NotNull 'PGbool)
686+
687+-- | >>> printSQL true
688+-- TRUE
689+true :: Condition schema relations grouping params
690+true = UnsafeExpression "TRUE"
691+
692+-- | >>> printSQL false
693+-- FALSE
694+false :: Condition schema relations grouping params
695+false = UnsafeExpression "FALSE"
696+
697+-- | >>> printSQL $ not_ true
698+-- (NOT TRUE)
699+not_
700+ :: Condition schema relations grouping params
701+ -> Condition schema relations grouping params
702+not_ = unsafeUnaryOp "NOT"
703+
704+-- | >>> printSQL $ true .&& false
705+-- (TRUE AND FALSE)
706+(.&&)
707+ :: Condition schema relations grouping params
708+ -> Condition schema relations grouping params
709+ -> Condition schema relations grouping params
710+(.&&) = unsafeBinaryOp "AND"
711+
712+-- | >>> printSQL $ true .|| false
713+-- (TRUE OR FALSE)
714+(.||)
715+ :: Condition schema relations grouping params
716+ -> Condition schema relations grouping params
717+ -> Condition schema relations grouping params
718+(.||) = unsafeBinaryOp "OR"
719+
720+-- | >>> :{
721+-- let
722+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
723+-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3
724+-- in printSQL expression
725+-- :}
726+-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END
727+caseWhenThenElse
728+ :: [ ( Condition schema relations grouping params
729+ , Expression schema relations grouping params (ty)
730+ ) ]
731+ -- ^ whens and thens
732+ -> Expression schema relations grouping params (ty)
733+ -- ^ else
734+ -> Expression schema relations grouping params (ty)
735+caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat
736+ [ "CASE"
737+ , mconcat
738+ [ mconcat
739+ [ " WHEN ", renderExpression when_
740+ , " THEN ", renderExpression then_
741+ ]
742+ | (when_,then_) <- whenThens
743+ ]
744+ , " ELSE ", renderExpression else_
745+ , " END"
746+ ]
747+
748+-- | >>> :{
749+-- let
750+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
751+-- expression = ifThenElse true 1 0
752+-- in printSQL expression
753+-- :}
754+-- CASE WHEN TRUE THEN 1 ELSE 0 END
755+ifThenElse
756+ :: Condition schema relations grouping params
757+ -> Expression schema relations grouping params (ty) -- ^ then
758+ -> Expression schema relations grouping params (ty) -- ^ else
759+ -> Expression schema relations grouping params (ty)
760+ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_
761+
762+-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`
763+-- will produce @NULL@s if one of their arguments is @NULL@.
764+--
765+-- >>> printSQL $ notNull true .== null_
766+-- (TRUE = NULL)
767+(.==)
768+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
769+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
770+ -> Expression schema relations grouping params (nullity 'PGbool)
771+(.==) = unsafeBinaryOp "="
772+infix 4 .==
773+
774+-- | >>> printSQL $ notNull true ./= null_
775+-- (TRUE <> NULL)
776+(./=)
777+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
778+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
779+ -> Expression schema relations grouping params (nullity 'PGbool)
780+(./=) = unsafeBinaryOp "<>"
781+infix 4 ./=
782+
783+-- | >>> printSQL $ notNull true .>= null_
784+-- (TRUE >= NULL)
785+(.>=)
786+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
787+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
788+ -> Expression schema relations grouping params (nullity 'PGbool)
789+(.>=) = unsafeBinaryOp ">="
790+infix 4 .>=
791+
792+-- | >>> printSQL $ notNull true .< null_
793+-- (TRUE < NULL)
794+(.<)
795+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
796+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
797+ -> Expression schema relations grouping params (nullity 'PGbool)
798+(.<) = unsafeBinaryOp "<"
799+infix 4 .<
800+
801+-- | >>> printSQL $ notNull true .<= null_
802+-- (TRUE <= NULL)
803+(.<=)
804+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
805+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
806+ -> Expression schema relations grouping params (nullity 'PGbool)
807+(.<=) = unsafeBinaryOp "<="
808+infix 4 .<=
809+
810+-- | >>> printSQL $ notNull true .> null_
811+-- (TRUE > NULL)
812+(.>)
813+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
814+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
815+ -> Expression schema relations grouping params (nullity 'PGbool)
816+(.>) = unsafeBinaryOp ">"
817+infix 4 .>
818+
819+-- | >>> printSQL currentDate
820+-- CURRENT_DATE
821+currentDate
822+ :: Expression schema relations grouping params (nullity 'PGdate)
823+currentDate = UnsafeExpression "CURRENT_DATE"
824+
825+-- | >>> printSQL currentTime
826+-- CURRENT_TIME
827+currentTime
828+ :: Expression schema relations grouping params (nullity 'PGtimetz)
829+currentTime = UnsafeExpression "CURRENT_TIME"
830+
831+-- | >>> printSQL currentTimestamp
832+-- CURRENT_TIMESTAMP
833+currentTimestamp
834+ :: Expression schema relations grouping params (nullity 'PGtimestamptz)
835+currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"
836+
837+-- | >>> printSQL localTime
838+-- LOCALTIME
839+localTime
840+ :: Expression schema relations grouping params (nullity 'PGtime)
841+localTime = UnsafeExpression "LOCALTIME"
842+
843+-- | >>> printSQL localTimestamp
844+-- LOCALTIMESTAMP
845+localTimestamp
846+ :: Expression schema relations grouping params (nullity 'PGtimestamp)
847+localTimestamp = UnsafeExpression "LOCALTIMESTAMP"
848+
849+{-----------------------------------------
850+text
851+-----------------------------------------}
438
852
439instance IsString
853instance IsString
440− (Expression outer commons grp schemas params from (null 'PGtext)) where
854+ (Expression schema relations grouping params (nullity 'PGtext)) where
441 fromString str = UnsafeExpression $
855 fromString str = UnsafeExpression $
442 "E\'" <> fromString (escape =<< str) <> "\'"
856 "E\'" <> fromString (escape =<< str) <> "\'"
443−instance IsString
857+ where
444− (Expression outer commons grp schemas params from (null 'PGtsvector)) where
858+ escape = \case
445− fromString str = UnsafeExpression . parenthesized . (<> " :: tsvector") $
859+ '\NUL' -> "\\0"
446− "E\'" <> fromString (escape =<< str) <> "\'"
860+ '\'' -> "''"
447−instance IsString
861+ '"' -> "\\\""
448− (Expression outer commons grp schemas params from (null 'PGtsquery)) where
862+ '\b' -> "\\b"
449− fromString str = UnsafeExpression . parenthesized . (<> " :: tsquery") $
863+ '\n' -> "\\n"
450− "E\'" <> fromString (escape =<< str) <> "\'"
864+ '\r' -> "\\r"
865+ '\t' -> "\\t"
866+ '\\' -> "\\\\"
867+ c -> [c]
451
868
452instance Semigroup
869instance Semigroup
453− (Expression outer commons grp schemas params from (null ('PGvararray ty))) where
870+ (Expression schema relations grouping params (nullity 'PGtext)) where
454− (<>) = unsafeBinaryOp "||"
455−instance Semigroup
456− (Expression outer commons grp schemas params from (null 'PGjsonb)) where
457− (<>) = unsafeBinaryOp "||"
458−instance Semigroup
459− (Expression outer commons grp schemas params from (null 'PGtext)) where
460− (<>) = unsafeBinaryOp "||"
461−instance Semigroup
462− (Expression outer commons grp schemas params from (null 'PGtsvector)) where
463 (<>) = unsafeBinaryOp "||"
871 (<>) = unsafeBinaryOp "||"
464
872
465instance Monoid
873instance Monoid
466− (Expression outer commons grp schemas params from (null 'PGtext)) where
874+ (Expression schema relations grouping params (nullity 'PGtext)) where
467− mempty = fromString ""
468− mappend = (<>)
469−instance Monoid
470− (Expression outer commons grp schemas params from (null 'PGtsvector)) where
471 mempty = fromString ""
875 mempty = fromString ""
472 mappend = (<>)
876 mappend = (<>)
877+
878+-- | >>> printSQL $ lower "ARRRGGG"
879+-- lower(E'ARRRGGG')
880+lower
881+ :: Expression schema relations grouping params (nullity 'PGtext)
882+ -- ^ string to lower case
883+ -> Expression schema relations grouping params (nullity 'PGtext)
884+lower = unsafeFunction "lower"
885+
886+-- | >>> printSQL $ upper "eeee"
887+-- upper(E'eeee')
888+upper
889+ :: Expression schema relations grouping params (nullity 'PGtext)
890+ -- ^ string to upper case
891+ -> Expression schema relations grouping params (nullity 'PGtext)
892+upper = unsafeFunction "upper"
893+
894+-- | >>> printSQL $ charLength "four"
895+-- char_length(E'four')
896+charLength
897+ :: Expression schema relations grouping params (nullity 'PGtext)
898+ -- ^ string to measure
899+ -> Expression schema relations grouping params (nullity 'PGint4)
900+charLength = unsafeFunction "char_length"
901+
902+-- | The `like` expression returns true if the @string@ matches
903+-- the supplied @pattern@. If @pattern@ does not contain percent signs
904+-- or underscores, then the pattern only represents the string itself;
905+-- in that case `like` acts like the equals operator. An underscore (_)
906+-- in pattern stands for (matches) any single character; a percent sign (%)
907+-- matches any sequence of zero or more characters.
908+--
909+-- >>> printSQL $ "abc" `like` "a%"
910+-- (E'abc' LIKE E'a%')
911+like
912+ :: Expression schema relations grouping params (nullity 'PGtext)
913+ -- ^ string
914+ -> Expression schema relations grouping params (nullity 'PGtext)
915+ -- ^ pattern
916+ -> Expression schema relations grouping params (nullity 'PGbool)
917+like = unsafeBinaryOp "LIKE"
918+
919+{-----------------------------------------
920+ -- json and jsonb support
921+
922+See https://www.postgresql.org/docs/10/static/functions-json.html -- most
923+comments lifted directly from this page.
924+
925+Table 9.44: json and jsonb operators
926+-----------------------------------------}
927+
928+-- | Get JSON value (object field or array element) at a key.
929+(.->)
930+ :: (PGjson_ json, PGjsonKey key)
931+ => Expression schema relations grouping params (nullity json)
932+ -> Expression schema relations grouping params (nullity key)
933+ -> Expression schema relations grouping params ('Null json)
934+(.->) = unsafeBinaryOp "->"
935+
936+-- | Get JSON value (object field or array element) at a key, as text.
937+(.->>)
938+ :: (PGjson_ json, PGjsonKey key)
939+ => Expression schema relations grouping params (nullity json)
940+ -> Expression schema relations grouping params (nullity key)
941+ -> Expression schema relations grouping params ('Null 'PGtext)
942+(.->>) = unsafeBinaryOp "->>"
943+
944+-- | Get JSON value at a specified path.
945+(.#>)
946+ :: (PGjson_ json, PGtextArray "(.#>)" path)
947+ => Expression schema relations grouping params (nullity json)
948+ -> Expression schema relations grouping params (nullity path)
949+ -> Expression schema relations grouping params ('Null json)
950+(.#>) = unsafeBinaryOp "#>"
951+
952+-- | Get JSON value at a specified path as text.
953+(.#>>)
954+ :: (PGjson_ json, PGtextArray "(.#>>)" path)
955+ => Expression schema relations grouping params (nullity json)
956+ -> Expression schema relations grouping params (nullity path)
957+ -> Expression schema relations grouping params ('Null 'PGtext)
958+(.#>>) = unsafeBinaryOp "#>>"
959+
960+-- Additional jsonb operators
961+
962+-- | Does the left JSON value contain the right JSON path/value entries at the
963+-- top level?
964+(.@>)
965+ :: Expression schema relations grouping params (nullity 'PGjsonb)
966+ -> Expression schema relations grouping params (nullity 'PGjsonb)
967+ -> Expression schema relations grouping params ('NotNull 'PGbool)
968+(.@>) = unsafeBinaryOp "@>"
969+
970+-- | Are the left JSON path/value entries contained at the top level within the
971+-- right JSON value?
972+(.<@)
973+ :: Expression schema relations grouping params (nullity 'PGjsonb)
974+ -> Expression schema relations grouping params (nullity 'PGjsonb)
975+ -> Expression schema relations grouping params ('NotNull 'PGbool)
976+(.<@) = unsafeBinaryOp "<@"
977+
978+-- | Does the string exist as a top-level key within the JSON value?
979+(.?)
980+ :: Expression schema relations grouping params (nullity 'PGjsonb)
981+ -> Expression schema relations grouping params (nullity 'PGtext)
982+ -> Expression schema relations grouping params ('NotNull 'PGbool)
983+(.?) = unsafeBinaryOp "?"
984+
985+-- | Do any of these array strings exist as top-level keys?
986+(.?|)
987+ :: Expression schema relations grouping params (nullity 'PGjsonb)
988+ -> Expression schema relations grouping params (nullity ('PGvararray 'PGtext))
989+ -> Expression schema relations grouping params ('NotNull 'PGbool)
990+(.?|) = unsafeBinaryOp "?|"
991+
992+-- | Do all of these array strings exist as top-level keys?
993+(.?&)
994+ :: Expression schema relations grouping params (nullity 'PGjsonb)
995+ -> Expression schema relations grouping params (nullity ('PGvararray 'PGtext))
996+ -> Expression schema relations grouping params ('NotNull 'PGbool)
997+(.?&) = unsafeBinaryOp "?&"
998+
999+-- | Concatenate two jsonb values into a new jsonb value.
1000+(.||.)
1001+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1002+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1003+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1004+(.||.) = unsafeBinaryOp "||"
1005+
1006+-- | Delete a key or keys from a JSON object, or remove an array element.
1007+--
1008+-- If the right operand is..
1009+--
1010+-- @ text @: Delete key/value pair or string element from left operand. Key/value pairs
1011+-- are matched based on their key value.
1012+--
1013+-- @ text[] @: Delete multiple key/value pairs or string elements
1014+-- from left operand. Key/value pairs are matched based on their key value.
1015+--
1016+-- @ integer @: Delete the array element with specified index (Negative integers
1017+-- count from the end). Throws an error if top level container is not an array.
1018+(.-.)
1019+ :: (key `In` '[ 'PGtext, 'PGvararray 'PGtext, 'PGint4, 'PGint2 ]) -- hlint error without parens here
1020+ => Expression schema relations grouping params (nullity 'PGjsonb)
1021+ -> Expression schema relations grouping params (nullity key)
1022+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1023+(.-.) = unsafeBinaryOp "-"
1024+
1025+-- | Delete the field or element with specified path (for JSON arrays, negative
1026+-- integers count from the end)
1027+(#-.)
1028+ :: PGtextArray "(#-.)" arrayty
1029+ => Expression schema relations grouping params (nullity 'PGjsonb)
1030+ -> Expression schema relations grouping params (nullity arrayty)
1031+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1032+(#-.) = unsafeBinaryOp "#-"
1033+
1034+{-----------------------------------------
1035+Table 9.45: JSON creation functions
1036+-----------------------------------------}
1037+
1038+-- | Returns the value as json. Arrays and composites are converted
1039+-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1040+-- type to json, the cast function will be used to perform the conversion;
1041+-- otherwise, a scalar value is produced. For any scalar type other than a
1042+-- number, a Boolean, or a null value, the text representation will be used, in
1043+-- such a fashion that it is a valid json value.
1044+toJson
1045+ :: Expression schema relations grouping params (nullity ty)
1046+ -> Expression schema relations grouping params (nullity 'PGjson)
1047+toJson = unsafeFunction "to_json"
1048+
1049+-- | Returns the value as jsonb. Arrays and composites are converted
1050+-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1051+-- type to json, the cast function will be used to perform the conversion;
1052+-- otherwise, a scalar value is produced. For any scalar type other than a
1053+-- number, a Boolean, or a null value, the text representation will be used, in
1054+-- such a fashion that it is a valid jsonb value.
1055+toJsonb
1056+ :: Expression schema relations grouping params (nullity ty)
1057+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1058+toJsonb = unsafeUnaryOp "to_jsonb"
1059+
1060+-- | Returns the array as a JSON array. A PostgreSQL multidimensional array
1061+-- becomes a JSON array of arrays. Line feeds will be added between dimension-1
1062+-- elements if pretty_bool is true.
1063+arrayToJson
1064+ :: PGarray "arrayToJson" arr
1065+ => Expression schema relations grouping params (nullity arr)
1066+ -> Expression schema relations grouping params (nullity 'PGjson)
1067+arrayToJson = unsafeFunction "array_to_json"
1068+
1069+-- | Returns the row as a JSON object. Line feeds will be added between level-1
1070+-- elements if pretty_bool is true.
1071+rowToJson
1072+ :: Expression schema relations grouping params (nullity ('PGcomposite ty))
1073+ -> Expression schema relations grouping params (nullity 'PGjson)
1074+rowToJson = unsafeFunction "row_to_json"
1075+
1076+-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic
1077+-- argument list.
1078+jsonBuildArray
1079+ :: SListI elems
1080+ => NP (Expression schema relations grouping params) elems
1081+ -> Expression schema relations grouping params (nullity 'PGjson)
1082+jsonBuildArray = unsafeVariadicFunction "json_build_array"
1083+
1084+-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a
1085+-- variadic argument list.
1086+jsonbBuildArray
1087+ :: SListI elems
1088+ => NP (Expression schema relations grouping params) elems
1089+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1090+jsonbBuildArray = unsafeVariadicFunction "jsonb_build_array"
1091+
1092+-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic
1093+-- argument list. The elements of the argument list must alternate between text
1094+-- and values.
1095+jsonBuildObject
1096+ :: (PGobjectpairs "jsonBuildObject" elems, SListI elems)
1097+ => NP (Expression schema relations grouping params) elems
1098+ -> Expression schema relations grouping params (nullity 'PGjson)
1099+jsonBuildObject = unsafeVariadicFunction "json_build_object"
1100+
1101+-- | Builds a possibly-heterogeneously-typed (binary) JSON object out of a
1102+-- variadic argument list. The elements of the argument list must alternate
1103+-- between text and values.
1104+jsonbBuildObject
1105+ :: (PGobjectpairs "jsonbBuildObject" elems, SListI elems)
1106+ => NP (Expression schema relations grouping params) elems
1107+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1108+jsonbBuildObject = unsafeVariadicFunction "jsonb_build_object"
1109+
1110+-- | Builds a JSON object out of a text array. The array must have either
1111+-- exactly one dimension with an even number of members, in which case they are
1112+-- taken as alternating key/value pairs, or two dimensions such that each inner
1113+-- array has exactly two elements, which are taken as a key/value pair.
1114+jsonObject
1115+ :: PGarrayOf "jsonObject" arr 'PGtext
1116+ => Expression schema relations grouping params (nullity arr)
1117+ -> Expression schema relations grouping params (nullity 'PGjson)
1118+jsonObject = unsafeFunction "json_object"
1119+
1120+-- | Builds a binary JSON object out of a text array. The array must have either
1121+-- exactly one dimension with an even number of members, in which case they are
1122+-- taken as alternating key/value pairs, or two dimensions such that each inner
1123+-- array has exactly two elements, which are taken as a key/value pair.
1124+jsonbObject
1125+ :: PGarrayOf "jsonbObject" arr 'PGtext
1126+ => Expression schema relations grouping params (nullity arr)
1127+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1128+jsonbObject = unsafeFunction "jsonb_object"
1129+
1130+-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1131+-- keys and one for values, that are zipped pairwise to create a JSON object.
1132+jsonZipObject
1133+ :: ( PGarrayOf "jsonZipObject" keysArray 'PGtext
1134+ , PGarrayOf "jsonZipObject" valuesArray 'PGtext)
1135+ => Expression schema relations grouping params (nullity keysArray)
1136+ -> Expression schema relations grouping params (nullity valuesArray)
1137+ -> Expression schema relations grouping params (nullity 'PGjson)
1138+jsonZipObject ks vs =
1139+ unsafeVariadicFunction "json_object" (ks :* vs :* Nil)
1140+
1141+-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1142+-- keys and one for values, that are zipped pairwise to create a binary JSON
1143+-- object.
1144+jsonbZipObject
1145+ :: ( PGarrayOf "jsonbZipObject" keysArray 'PGtext
1146+ , PGarrayOf "jsonbZipObject" valuesArray 'PGtext)
1147+ => Expression schema relations grouping params (nullity keysArray)
1148+ -> Expression schema relations grouping params (nullity valuesArray)
1149+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1150+jsonbZipObject ks vs =
1151+ unsafeVariadicFunction "jsonb_object" (ks :* vs :* Nil)
1152+
1153+{-----------------------------------------
1154+Table 9.46: JSON processing functions
1155+-----------------------------------------}
1156+
1157+-- | Returns the number of elements in the outermost JSON array.
1158+jsonArrayLength
1159+ :: Expression schema relations grouping params (nullity 'PGjson)
1160+ -> Expression schema relations grouping params (nullity 'PGint4)
1161+jsonArrayLength = unsafeFunction "json_array_length"
1162+
1163+-- | Returns the number of elements in the outermost binary JSON array.
1164+jsonbArrayLength
1165+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1166+ -> Expression schema relations grouping params (nullity 'PGint4)
1167+jsonbArrayLength = unsafeFunction "jsonb_array_length"
1168+
1169+-- | Expands the outermost JSON object into a set of key/value pairs.
1170+--
1171+-- See also 'Squeal.PostgreSQL.Query.jsonEach'.
1172+jsonEachAsComposite
1173+ :: Expression schema relations grouping params (nullity 'PGjson)
1174+ -> Expression schema relations grouping params
1175+ (nullity ('PGcomposite '[ "key" ::: 'PGtext, "value" ::: 'PGjson ]))
1176+jsonEachAsComposite = unsafeFunction "json_each"
1177+
1178+-- | Expands the outermost JSON object into a set of key/value pairs.
1179+--
1180+-- See also 'Squeal.PostgreSQL.Query.jsonbEach'
1181+jsonbEachAsComposite
1182+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1183+ -> Expression schema relations grouping params
1184+ (nullity ('PGcomposite '[ "key" ::: 'PGtext, "value" ::: 'PGjsonb ]))
1185+jsonbEachAsComposite = unsafeFunction "jsonb_each"
1186+
1187+-- | Expands the outermost JSON object into a set of key/value pairs.
1188+--
1189+-- See also 'Squeal.PostgreSQL.Query.jsonEachText'.
1190+jsonEachTextAsComposite
1191+ :: Expression schema relations grouping params (nullity 'PGjson)
1192+ -> Expression schema relations grouping params
1193+ (nullity ('PGcomposite '[ "key" ::: 'PGtext, "value" ::: 'PGtext ]))
1194+jsonEachTextAsComposite = unsafeFunction "json_each_text"
1195+
1196+-- | Expands the outermost JSON object into a set of key/value pairs.
1197+--
1198+-- See also 'Squeal.PostgreSQL.Query.jsonbEachText'
1199+jsonbEachTextAsComposite
1200+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1201+ -> Expression schema relations grouping params
1202+ (nullity ('PGcomposite '[ "key" ::: 'PGtext, "value" ::: 'PGtext ]))
1203+jsonbEachTextAsComposite = unsafeFunction "jsonb_each_text"
1204+
1205+-- | Returns JSON value pointed to by path_elems (equivalent to #> operator).
1206+jsonExtractPath
1207+ :: SListI elems
1208+ => Expression schema relations grouping params (nullity 'PGjson)
1209+ -> NP (Expression schema relations grouping params) elems
1210+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1211+jsonExtractPath x xs =
1212+ unsafeVariadicFunction "json_extract_path" (x :* xs)
1213+
1214+-- | Returns JSON value pointed to by path_elems (equivalent to #> operator).
1215+jsonbExtractPath
1216+ :: SListI elems
1217+ => Expression schema relations grouping params (nullity 'PGjsonb)
1218+ -> NP (Expression schema relations grouping params) elems
1219+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1220+jsonbExtractPath x xs =
1221+ unsafeVariadicFunction "jsonb_extract_path" (x :* xs)
1222+
1223+-- | Returns JSON value pointed to by path_elems (equivalent to #> operator),
1224+-- as text.
1225+jsonExtractPathText
1226+ :: SListI elems
1227+ => Expression schema relations grouping params (nullity 'PGjson)
1228+ -> NP (Expression schema relations grouping params) elems
1229+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1230+jsonExtractPathText x xs =
1231+ unsafeVariadicFunction "json_extract_path_text" (x :* xs)
1232+
1233+-- | Returns JSON value pointed to by path_elems (equivalent to #> operator),
1234+-- as text.
1235+jsonbExtractPathText
1236+ :: SListI elems
1237+ => Expression schema relations grouping params (nullity 'PGjsonb)
1238+ -> NP (Expression schema relations grouping params) elems
1239+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1240+jsonbExtractPathText x xs =
1241+ unsafeVariadicFunction "jsonb_extract_path_text" (x :* xs)
1242+
1243+-- | Returns set of keys in the outermost JSON object.
1244+jsonObjectKeys
1245+ :: Expression schema relations grouping params (nullity 'PGjson)
1246+ -> Expression schema relations grouping params (nullity 'PGtext)
1247+jsonObjectKeys = unsafeFunction "json_object_keys"
1248+
1249+-- | Returns set of keys in the outermost JSON object.
1250+jsonbObjectKeys
1251+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1252+ -> Expression schema relations grouping params (nullity 'PGtext)
1253+jsonbObjectKeys = unsafeFunction "jsonb_object_keys"
1254+
1255+{-----------------------------------------
1256+aggregation
1257+-----------------------------------------}
1258+
1259+-- | escape hatch to define aggregate functions
1260+unsafeAggregate
1261+ :: ByteString -- ^ aggregate function
1262+ -> Expression schema relations 'Ungrouped params (xty)
1263+ -> Expression schema relations ('Grouped bys) params (yty)
1264+unsafeAggregate fun x = UnsafeExpression $ mconcat
1265+ [fun, "(", renderExpression x, ")"]
1266+
1267+-- | escape hatch to define aggregate functions over distinct values
1268+unsafeAggregateDistinct
1269+ :: ByteString -- ^ aggregate function
1270+ -> Expression schema relations 'Ungrouped params (xty)
1271+ -> Expression schema relations ('Grouped bys) params (yty)
1272+unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat
1273+ [fun, "(DISTINCT ", renderExpression x, ")"]
1274+
1275+-- | >>> :{
1276+-- let
1277+-- expression :: Expression schema '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Grouped bys) params ('Null 'PGnumeric)
1278+-- expression = sum_ #col
1279+-- in printSQL expression
1280+-- :}
1281+-- sum("col")
1282+sum_
1283+ :: PGNum ty
1284+ => Expression schema relations 'Ungrouped params (nullity ty)
1285+ -- ^ what to sum
1286+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1287+sum_ = unsafeAggregate "sum"
1288+
1289+-- | >>> :{
1290+-- let
1291+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGnumeric]] ('Grouped bys) params (nullity 'PGnumeric)
1292+-- expression = sumDistinct #col
1293+-- in printSQL expression
1294+-- :}
1295+-- sum(DISTINCT "col")
1296+sumDistinct
1297+ :: PGNum ty
1298+ => Expression schema relations 'Ungrouped params (nullity ty)
1299+ -- ^ what to sum
1300+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1301+sumDistinct = unsafeAggregateDistinct "sum"
1302+
1303+-- | A constraint for `PGType`s that you can take averages of and the resulting
1304+-- `PGType`.
1305+class PGAvg ty avg | ty -> avg where
1306+ avg, avgDistinct
1307+ :: Expression schema relations 'Ungrouped params (nullity ty)
1308+ -- ^ what to average
1309+ -> Expression schema relations ('Grouped bys) params (nullity avg)
1310+ avg = unsafeAggregate "avg"
1311+ avgDistinct = unsafeAggregateDistinct "avg"
1312+instance PGAvg 'PGint2 'PGnumeric
1313+instance PGAvg 'PGint4 'PGnumeric
1314+instance PGAvg 'PGint8 'PGnumeric
1315+instance PGAvg 'PGnumeric 'PGnumeric
1316+instance PGAvg 'PGfloat4 'PGfloat8
1317+instance PGAvg 'PGfloat8 'PGfloat8
1318+instance PGAvg 'PGinterval 'PGinterval
1319+
1320+-- | >>> :{
1321+-- let
1322+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1323+-- expression = bitAnd #col
1324+-- in printSQL expression
1325+-- :}
1326+-- bit_and("col")
1327+bitAnd
1328+ :: PGIntegral int
1329+ => Expression schema relations 'Ungrouped params (nullity int)
1330+ -- ^ what to aggregate
1331+ -> Expression schema relations ('Grouped bys) params (nullity int)
1332+bitAnd = unsafeAggregate "bit_and"
1333+
1334+-- | >>> :{
1335+-- let
1336+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1337+-- expression = bitOr #col
1338+-- in printSQL expression
1339+-- :}
1340+-- bit_or("col")
1341+bitOr
1342+ :: PGIntegral int
1343+ => Expression schema relations 'Ungrouped params (nullity int)
1344+ -- ^ what to aggregate
1345+ -> Expression schema relations ('Grouped bys) params (nullity int)
1346+bitOr = unsafeAggregate "bit_or"
1347+
1348+-- | >>> :{
1349+-- let
1350+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1351+-- expression = bitAndDistinct #col
1352+-- in printSQL expression
1353+-- :}
1354+-- bit_and(DISTINCT "col")
1355+bitAndDistinct
1356+ :: PGIntegral int
1357+ => Expression schema relations 'Ungrouped params (nullity int)
1358+ -- ^ what to aggregate
1359+ -> Expression schema relations ('Grouped bys) params (nullity int)
1360+bitAndDistinct = unsafeAggregateDistinct "bit_and"
1361+
1362+-- | >>> :{
1363+-- let
1364+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1365+-- expression = bitOrDistinct #col
1366+-- in printSQL expression
1367+-- :}
1368+-- bit_or(DISTINCT "col")
1369+bitOrDistinct
1370+ :: PGIntegral int
1371+ => Expression schema relations 'Ungrouped params (nullity int)
1372+ -- ^ what to aggregate
1373+ -> Expression schema relations ('Grouped bys) params (nullity int)
1374+bitOrDistinct = unsafeAggregateDistinct "bit_or"
1375+
1376+-- | >>> :{
1377+-- let
1378+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1379+-- expression = boolAnd #col
1380+-- in printSQL expression
1381+-- :}
1382+-- bool_and("col")
1383+boolAnd
1384+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1385+ -- ^ what to aggregate
1386+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1387+boolAnd = unsafeAggregate "bool_and"
1388+
1389+-- | >>> :{
1390+-- let
1391+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1392+-- expression = boolOr #col
1393+-- in printSQL expression
1394+-- :}
1395+-- bool_or("col")
1396+boolOr
1397+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1398+ -- ^ what to aggregate
1399+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1400+boolOr = unsafeAggregate "bool_or"
1401+
1402+-- | >>> :{
1403+-- let
1404+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1405+-- expression = boolAndDistinct #col
1406+-- in printSQL expression
1407+-- :}
1408+-- bool_and(DISTINCT "col")
1409+boolAndDistinct
1410+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1411+ -- ^ what to aggregate
1412+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1413+boolAndDistinct = unsafeAggregateDistinct "bool_and"
1414+
1415+-- | >>> :{
1416+-- let
1417+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1418+-- expression = boolOrDistinct #col
1419+-- in printSQL expression
1420+-- :}
1421+-- bool_or(DISTINCT "col")
1422+boolOrDistinct
1423+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1424+ -- ^ what to aggregate
1425+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1426+boolOrDistinct = unsafeAggregateDistinct "bool_or"
1427+
1428+-- | A special aggregation that does not require an input
1429+--
1430+-- >>> printSQL countStar
1431+-- count(*)
1432+countStar
1433+ :: Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1434+countStar = UnsafeExpression $ "count(*)"
1435+
1436+-- | >>> :{
1437+-- let
1438+-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)
1439+-- expression = count #col
1440+-- in printSQL expression
1441+-- :}
1442+-- count("col")
1443+count
1444+ :: Expression schema relations 'Ungrouped params ty
1445+ -- ^ what to count
1446+ -> Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1447+count = unsafeAggregate "count"
1448+
1449+-- | >>> :{
1450+-- let
1451+-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)
1452+-- expression = countDistinct #col
1453+-- in printSQL expression
1454+-- :}
1455+-- count(DISTINCT "col")
1456+countDistinct
1457+ :: Expression schema relations 'Ungrouped params ty
1458+ -- ^ what to count
1459+ -> Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1460+countDistinct = unsafeAggregateDistinct "count"
1461+
1462+-- | synonym for `boolAnd`
1463+--
1464+-- >>> :{
1465+-- let
1466+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1467+-- expression = every #col
1468+-- in printSQL expression
1469+-- :}
1470+-- every("col")
1471+every
1472+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1473+ -- ^ what to aggregate
1474+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1475+every = unsafeAggregate "every"
1476+
1477+-- | synonym for `boolAndDistinct`
1478+--
1479+-- >>> :{
1480+-- let
1481+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1482+-- expression = everyDistinct #col
1483+-- in printSQL expression
1484+-- :}
1485+-- every(DISTINCT "col")
1486+everyDistinct
1487+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1488+ -- ^ what to aggregate
1489+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1490+everyDistinct = unsafeAggregateDistinct "every"
1491+
1492+-- | minimum and maximum aggregation
1493+max_, min_, maxDistinct, minDistinct
1494+ :: Expression schema relations 'Ungrouped params (nullity ty)
1495+ -- ^ what to aggregate
1496+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1497+max_ = unsafeAggregate "max"
1498+min_ = unsafeAggregate "min"
1499+maxDistinct = unsafeAggregateDistinct "max"
1500+minDistinct = unsafeAggregateDistinct "min"
1501+
1502+{-----------------------------------------
1503+type expressions
1504+-----------------------------------------}
1505+
1506+-- | `TypeExpression`s are used in `cast`s and `createTable` commands.
1507+newtype TypeExpression (schema :: SchemaType) (ty :: PGType)
1508+ = UnsafeTypeExpression { renderTypeExpression :: ByteString }
1509+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
1510+
1511+instance (Has alias schema ('Typedef ty))
1512+ => IsLabel alias (TypeExpression schema ty) where
1513+ fromLabel = UnsafeTypeExpression (renderAlias (fromLabel @alias))
1514+
1515+-- | logical Boolean (true/false)
1516+bool :: TypeExpression schema 'PGbool
1517+bool = UnsafeTypeExpression "bool"
1518+-- | signed two-byte integer
1519+int2, smallint :: TypeExpression schema 'PGint2
1520+int2 = UnsafeTypeExpression "int2"
1521+smallint = UnsafeTypeExpression "smallint"
1522+-- | signed four-byte integer
1523+int4, int, integer :: TypeExpression schema 'PGint4
1524+int4 = UnsafeTypeExpression "int4"
1525+int = UnsafeTypeExpression "int"
1526+integer = UnsafeTypeExpression "integer"
1527+-- | signed eight-byte integer
1528+int8, bigint :: TypeExpression schema 'PGint8
1529+int8 = UnsafeTypeExpression "int8"
1530+bigint = UnsafeTypeExpression "bigint"
1531+-- | arbitrary precision numeric type
1532+numeric :: TypeExpression schema 'PGnumeric
1533+numeric = UnsafeTypeExpression "numeric"
1534+-- | single precision floating-point number (4 bytes)
1535+float4, real :: TypeExpression schema 'PGfloat4
1536+float4 = UnsafeTypeExpression "float4"
1537+real = UnsafeTypeExpression "real"
1538+-- | double precision floating-point number (8 bytes)
1539+float8, doublePrecision :: TypeExpression schema 'PGfloat8
1540+float8 = UnsafeTypeExpression "float8"
1541+doublePrecision = UnsafeTypeExpression "double precision"
1542+-- | variable-length character string
1543+text :: TypeExpression schema 'PGtext
1544+text = UnsafeTypeExpression "text"
1545+-- | fixed-length character string
1546+char, character
1547+ :: (KnownNat n, 1 <= n)
1548+ => proxy n
1549+ -> TypeExpression schema ('PGchar n)
1550+char p = UnsafeTypeExpression $ "char(" <> renderNat p <> ")"
1551+character p = UnsafeTypeExpression $ "character(" <> renderNat p <> ")"
1552+-- | variable-length character string
1553+varchar, characterVarying
1554+ :: (KnownNat n, 1 <= n)
1555+ => proxy n
1556+ -> TypeExpression schema ('PGvarchar n)
1557+varchar p = UnsafeTypeExpression $ "varchar(" <> renderNat p <> ")"
1558+characterVarying p = UnsafeTypeExpression $
1559+ "character varying(" <> renderNat p <> ")"
1560+-- | binary data ("byte array")
1561+bytea :: TypeExpression schema 'PGbytea
1562+bytea = UnsafeTypeExpression "bytea"
1563+-- | date and time (no time zone)
1564+timestamp :: TypeExpression schema 'PGtimestamp
1565+timestamp = UnsafeTypeExpression "timestamp"
1566+-- | date and time, including time zone
1567+timestampWithTimeZone :: TypeExpression schema 'PGtimestamptz
1568+timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"
1569+-- | calendar date (year, month, day)
1570+date :: TypeExpression schema 'PGdate
1571+date = UnsafeTypeExpression "date"
1572+-- | time of day (no time zone)
1573+time :: TypeExpression schema 'PGtime
1574+time = UnsafeTypeExpression "time"
1575+-- | time of day, including time zone
1576+timeWithTimeZone :: TypeExpression schema 'PGtimetz
1577+timeWithTimeZone = UnsafeTypeExpression "time with time zone"
1578+-- | time span
1579+interval :: TypeExpression schema 'PGinterval
1580+interval = UnsafeTypeExpression "interval"
1581+-- | universally unique identifier
1582+uuid :: TypeExpression schema 'PGuuid
1583+uuid = UnsafeTypeExpression "uuid"
1584+-- | IPv4 or IPv6 host address
1585+inet :: TypeExpression schema 'PGinet
1586+inet = UnsafeTypeExpression "inet"
1587+-- | textual JSON data
1588+json :: TypeExpression schema 'PGjson
1589+json = UnsafeTypeExpression "json"
1590+-- | binary JSON data, decomposed
1591+jsonb :: TypeExpression schema 'PGjsonb
1592+jsonb = UnsafeTypeExpression "jsonb"
1593+-- | variable length array
1594+vararray
1595+ :: TypeExpression schema pg
1596+ -> TypeExpression schema ('PGvararray pg)
1597+vararray ty = UnsafeTypeExpression $ renderTypeExpression ty <> "[]"
1598+-- | fixed length array
1599+--
1600+-- >>> renderTypeExpression (fixarray (Proxy @2) json)
1601+-- "json[2]"
1602+fixarray
1603+ :: KnownNat n
1604+ => proxy n
1605+ -> TypeExpression schema pg
1606+ -> TypeExpression schema ('PGfixarray n pg)
1607+fixarray p ty = UnsafeTypeExpression $
1608+ renderTypeExpression ty <> "[" <> renderNat p <> "]"
1609+
1610+-- | `pgtype` is a demoted version of a `PGType`
1611+class PGTyped schema (ty :: PGType) where pgtype :: TypeExpression schema ty
1612+instance PGTyped schema 'PGbool where pgtype = bool
1613+instance PGTyped schema 'PGint2 where pgtype = int2
1614+instance PGTyped schema 'PGint4 where pgtype = int4
1615+instance PGTyped schema 'PGint8 where pgtype = int8
1616+instance PGTyped schema 'PGnumeric where pgtype = numeric
1617+instance PGTyped schema 'PGfloat4 where pgtype = float4
1618+instance PGTyped schema 'PGfloat8 where pgtype = float8
1619+instance PGTyped schema 'PGtext where pgtype = text
1620+instance (KnownNat n, 1 <= n)
1621+ => PGTyped schema ('PGchar n) where pgtype = char (Proxy @n)
1622+instance (KnownNat n, 1 <= n)
1623+ => PGTyped schema ('PGvarchar n) where pgtype = varchar (Proxy @n)
1624+instance PGTyped schema 'PGbytea where pgtype = bytea
1625+instance PGTyped schema 'PGtimestamp where pgtype = timestamp
1626+instance PGTyped schema 'PGtimestamptz where pgtype = timestampWithTimeZone
1627+instance PGTyped schema 'PGdate where pgtype = date
1628+instance PGTyped schema 'PGtime where pgtype = time
1629+instance PGTyped schema 'PGtimetz where pgtype = timeWithTimeZone
1630+instance PGTyped schema 'PGinterval where pgtype = interval
1631+instance PGTyped schema 'PGuuid where pgtype = uuid
1632+instance PGTyped schema 'PGjson where pgtype = json
1633+instance PGTyped schema 'PGjsonb where pgtype = jsonb
1634+instance PGTyped schema ty => PGTyped schema ('PGvararray ty) where
1635+ pgtype = vararray (pgtype @schema @ty)
1636+instance (KnownNat n, PGTyped schema ty) => PGTyped schema ('PGfixarray n ty) where
1637+ pgtype = fixarray (Proxy @n) (pgtype @schema @ty)
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hsdeleted−462
@@ -1,462 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Aggregate
3−Description: Aggregate functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Aggregate functions
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , DeriveGeneric
14− , FlexibleContexts
15− , FlexibleInstances
16− , FunctionalDependencies
17− , LambdaCase
18− , MultiParamTypeClasses
19− , OverloadedStrings
20− , PolyKinds
21− , TypeFamilies
22− , TypeOperators
23− , UndecidableInstances
24−#-}
25−
26−module Squeal.PostgreSQL.Expression.Aggregate
27− ( Aggregate (..)
28− , Distinction (..)
29− , PGSum
30− , PGAvg
31− ) where
32−
33−import Control.DeepSeq
34−import Data.ByteString (ByteString)
35−import Data.Kind
36−import GHC.TypeLits
37−
38−import qualified GHC.Generics as GHC
39−import qualified Generics.SOP as SOP
40−
41−import Squeal.PostgreSQL.Alias
42−import Squeal.PostgreSQL.Expression
43−import Squeal.PostgreSQL.List
44−import Squeal.PostgreSQL.Render
45−import Squeal.PostgreSQL.Schema
46−
47−-- $setup
48−-- >>> import Squeal.PostgreSQL
49−
50−{- |
51−`Aggregate` functions compute a single result from a set of input values.
52−`Aggregate` functions can be used as `GroupedBy` `Expression`s as well
53−as `Squeal.PostgreSQL.Expression.Window.WindowFunction`s.
54−-}
55−class Aggregate expr1 exprN aggr
56− | aggr -> expr1, aggr -> exprN where
57−
58− -- | A special aggregation that does not require an input
59− --
60− -- >>> :{
61− -- let
62− -- expression :: Expression '[] commons ('Grouped bys) schemas params from ('NotNull 'PGint8)
63− -- expression = countStar
64− -- in printSQL expression
65− -- :}
66− -- count(*)
67− countStar :: aggr ('NotNull 'PGint8)
68−
69− -- | >>> :{
70− -- let
71− -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null ty]] ('NotNull 'PGint8)
72− -- expression = count (All #col)
73− -- in printSQL expression
74− -- :}
75− -- count(ALL "col")
76− count
77− :: expr1 ty
78− -- ^ what to count
79− -> aggr ('NotNull 'PGint8)
80−
81− -- | >>> :{
82− -- let
83− -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Null 'PGnumeric)
84− -- expression = sum_ (Distinct #col)
85− -- in printSQL expression
86− -- :}
87− -- sum(DISTINCT "col")
88− sum_
89− :: expr1 (null ty)
90− -> aggr ('Null (PGSum ty))
91−
92− -- | input values, including nulls, concatenated into an array
93− arrayAgg
94− :: expr1 ty
95− -> aggr ('Null ('PGvararray ty))
96−
97− -- | aggregates values as a JSON array
98− jsonAgg
99− :: expr1 ty
100− -> aggr ('Null 'PGjson)
101−
102− -- | aggregates values as a JSON array
103− jsonbAgg
104− :: expr1 ty
105− -> aggr ('Null 'PGjsonb)
106−
107− {- |
108− the bitwise AND of all non-null input values, or null if none
109−
110− >>> :{
111− let
112− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)
113− expression = bitAnd (Distinct #col)
114− in printSQL expression
115− :}
116− bit_and(DISTINCT "col")
117− -}
118− bitAnd
119− :: int `In` PGIntegral
120− => expr1 (null int)
121− -- ^ what to aggregate
122− -> aggr ('Null int)
123−
124− {- |
125− the bitwise OR of all non-null input values, or null if none
126−
127− >>> :{
128− let
129− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)
130− expression = bitOr (All #col)
131− in printSQL expression
132− :}
133− bit_or(ALL "col")
134− -}
135− bitOr
136− :: int `In` PGIntegral
137− => expr1 (null int)
138− -- ^ what to aggregate
139− -> aggr ('Null int)
140−
141− {- |
142− true if all input values are true, otherwise false
143−
144− >>> :{
145− let
146− winFun :: WindowFunction '[] commons 'Ungrouped schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)
147− winFun = boolAnd #col
148− in printSQL winFun
149− :}
150− bool_and("col")
151− -}
152− boolAnd
153− :: expr1 (null 'PGbool)
154− -- ^ what to aggregate
155− -> aggr ('Null 'PGbool)
156−
157− {- |
158− true if at least one input value is true, otherwise false
159−
160− >>> :{
161− let
162− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)
163− expression = boolOr (All #col)
164− in printSQL expression
165− :}
166− bool_or(ALL "col")
167− -}
168− boolOr
169− :: expr1 (null 'PGbool)
170− -- ^ what to aggregate
171− -> aggr ('Null 'PGbool)
172−
173− {- |
174− equivalent to `boolAnd`
175−
176− >>> :{
177− let
178− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)
179− expression = every (Distinct #col)
180− in printSQL expression
181− :}
182− every(DISTINCT "col")
183− -}
184− every
185− :: expr1 (null 'PGbool)
186− -- ^ what to aggregate
187− -> aggr ('Null 'PGbool)
188−
189− {- |maximum value of expression across all input values-}
190− max_
191− :: expr1 (null ty)
192− -- ^ what to maximize
193− -> aggr ('Null ty)
194−
195− -- | minimum value of expression across all input values
196− min_
197− :: expr1 (null ty)
198− -- ^ what to minimize
199− -> aggr ('Null ty)
200−
201− -- | the average (arithmetic mean) of all input values
202− avg
203− :: expr1 (null ty)
204− -- ^ what to average
205− -> aggr ('Null (PGAvg ty))
206−
207− {- | correlation coefficient
208−
209− >>> :{
210− let
211− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
212− expression = corr (All (#y *: #x))
213− in printSQL expression
214− :}
215− corr(ALL "y", "x")
216− -}
217− corr
218− :: exprN '[null 'PGfloat8, null 'PGfloat8]
219− -> aggr ('Null 'PGfloat8)
220−
221− {- | population covariance
222−
223− >>> :{
224− let
225− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
226− expression = covarPop (All (#y *: #x))
227− in printSQL expression
228− :}
229− covar_pop(ALL "y", "x")
230− -}
231− covarPop
232− :: exprN '[null 'PGfloat8, null 'PGfloat8]
233− -> aggr ('Null 'PGfloat8)
234−
235− {- | sample covariance
236−
237− >>> :{
238− let
239− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
240− winFun = covarSamp (#y *: #x)
241− in printSQL winFun
242− :}
243− covar_samp("y", "x")
244− -}
245− covarSamp
246− :: exprN '[null 'PGfloat8, null 'PGfloat8]
247− -> aggr ('Null 'PGfloat8)
248−
249− {- | average of the independent variable (sum(X)/N)
250−
251− >>> :{
252− let
253− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
254− expression = regrAvgX (All (#y *: #x))
255− in printSQL expression
256− :}
257− regr_avgx(ALL "y", "x")
258− -}
259− regrAvgX
260− :: exprN '[null 'PGfloat8, null 'PGfloat8]
261− -> aggr ('Null 'PGfloat8)
262−
263− {- | average of the dependent variable (sum(Y)/N)
264−
265− >>> :{
266− let
267− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
268− winFun = regrAvgY (#y *: #x)
269− in printSQL winFun
270− :}
271− regr_avgy("y", "x")
272− -}
273− regrAvgY
274− :: exprN '[null 'PGfloat8, null 'PGfloat8]
275− -> aggr ('Null 'PGfloat8)
276−
277− {- | number of input rows in which both expressions are nonnull
278−
279− >>> :{
280− let
281− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGint8)
282− winFun = regrCount (#y *: #x)
283− in printSQL winFun
284− :}
285− regr_count("y", "x")
286− -}
287− regrCount
288− :: exprN '[null 'PGfloat8, null 'PGfloat8]
289− -> aggr ('Null 'PGint8)
290−
291− {- | y-intercept of the least-squares-fit linear equation determined by the (X, Y) pairs
292− >>> :{
293− let
294− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
295− expression = regrIntercept (All (#y *: #x))
296− in printSQL expression
297− :}
298− regr_intercept(ALL "y", "x")
299− -}
300− regrIntercept
301− :: exprN '[null 'PGfloat8, null 'PGfloat8]
302− -> aggr ('Null 'PGfloat8)
303−
304− -- | @regr_r2(Y, X)@, square of the correlation coefficient
305− regrR2
306− :: exprN '[null 'PGfloat8, null 'PGfloat8]
307− -> aggr ('Null 'PGfloat8)
308−
309− -- | @regr_slope(Y, X)@, slope of the least-squares-fit linear equation
310− -- determined by the (X, Y) pairs
311− regrSlope
312− :: exprN '[null 'PGfloat8, null 'PGfloat8]
313− -> aggr ('Null 'PGfloat8)
314−
315− -- | @regr_sxx(Y, X)@, sum(X^2) - sum(X)^2/N
316− -- (“sum of squares” of the independent variable)
317− regrSxx
318− :: exprN '[null 'PGfloat8, null 'PGfloat8]
319− -> aggr ('Null 'PGfloat8)
320−
321− -- | @regr_sxy(Y, X)@, sum(X*Y) - sum(X) * sum(Y)/N
322− -- (“sum of products” of independent times dependent variable)
323− regrSxy
324− :: exprN '[null 'PGfloat8, null 'PGfloat8]
325− -> aggr ('Null 'PGfloat8)
326−
327− -- | @regr_syy(Y, X)@, sum(Y^2) - sum(Y)^2/N
328− -- (“sum of squares” of the dependent variable)
329− regrSyy
330− :: exprN '[null 'PGfloat8, null 'PGfloat8]
331− -> aggr ('Null 'PGfloat8)
332−
333− -- | historical alias for `stddevSamp`
334− stddev
335− :: expr1 (null ty)
336− -> aggr ('Null (PGAvg ty))
337−
338− -- | population standard deviation of the input values
339− stddevPop
340− :: expr1 (null ty)
341− -> aggr ('Null (PGAvg ty))
342−
343− -- | sample standard deviation of the input values
344− stddevSamp
345− :: expr1 (null ty)
346− -> aggr ('Null (PGAvg ty))
347−
348− -- | historical alias for `varSamp`
349− variance
350− :: expr1 (null ty)
351− -> aggr ('Null (PGAvg ty))
352−
353− -- | population variance of the input values
354− -- (square of the population standard deviation)
355− varPop
356− :: expr1 (null ty)
357− -> aggr ('Null (PGAvg ty))
358−
359− -- | sample variance of the input values
360− -- (square of the sample standard deviation)
361− varSamp
362− :: expr1 (null ty)
363− -> aggr ('Null (PGAvg ty))
364−
365−{- |
366−`Distinction`s are used for the input of `Aggregate` `Expression`s.
367−`All` invokes the aggregate once for each input row.
368−`Distinct` invokes the aggregate once for each distinct value of the expression
369−(or distinct set of values, for multiple expressions) found in the input
370−-}
371−data Distinction (expr :: kind -> Type) (ty :: kind)
372− = All (expr ty)
373− | Distinct (expr ty)
374− deriving (GHC.Generic,Show,Eq,Ord)
375−instance NFData (Distinction (Expression outer commons grp schemas params from) ty)
376−instance RenderSQL (Distinction (Expression outer commons grp schemas params from) ty) where
377− renderSQL = \case
378− All x -> "ALL" <+> renderSQL x
379− Distinct x -> "DISTINCT" <+> renderSQL x
380−instance SOP.SListI tys => RenderSQL
381− (Distinction (NP (Expression outer commons grp schemas params from)) tys) where
382− renderSQL = \case
383− All xs -> "ALL" <+> renderCommaSeparated renderSQL xs
384− Distinct xs -> "DISTINCT" <+> renderCommaSeparated renderSQL xs
385−
386−instance Aggregate
387− (Distinction (Expression outer commons 'Ungrouped schemas params from))
388− (Distinction (NP (Expression outer commons 'Ungrouped schemas params from)))
389− (Expression outer commons ('Grouped bys) schemas params from) where
390− countStar = UnsafeExpression "count(*)"
391− count = unsafeAggregate1 "count"
392− sum_ = unsafeAggregate1 "sum"
393− arrayAgg = unsafeAggregate1 "array_agg"
394− jsonAgg = unsafeAggregate1 "json_agg"
395− jsonbAgg = unsafeAggregate1 "jsonb_agg"
396− bitAnd = unsafeAggregate1 "bit_and"
397− bitOr = unsafeAggregate1 "bit_or"
398− boolAnd = unsafeAggregate1 "bool_and"
399− boolOr = unsafeAggregate1 "bool_or"
400− every = unsafeAggregate1 "every"
401− max_ = unsafeAggregate1 "max"
402− min_ = unsafeAggregate1 "min"
403− avg = unsafeAggregate1 "avg"
404− corr = unsafeAggregateN "corr"
405− covarPop = unsafeAggregateN "covar_pop"
406− covarSamp = unsafeAggregateN "covar_samp"
407− regrAvgX = unsafeAggregateN "regr_avgx"
408− regrAvgY = unsafeAggregateN "regr_avgy"
409− regrCount = unsafeAggregateN "regr_count"
410− regrIntercept = unsafeAggregateN "regr_intercept"
411− regrR2 = unsafeAggregateN "regr_r2"
412− regrSlope = unsafeAggregateN "regr_slope"
413− regrSxx = unsafeAggregateN "regr_sxx"
414− regrSxy = unsafeAggregateN "regr_sxy"
415− regrSyy = unsafeAggregateN "regr_syy"
416− stddev = unsafeAggregate1 "stddev"
417− stddevPop = unsafeAggregate1 "stddev_pop"
418− stddevSamp = unsafeAggregate1 "stddev_samp"
419− variance = unsafeAggregate1 "variance"
420− varPop = unsafeAggregate1 "var_pop"
421− varSamp = unsafeAggregate1 "var_samp"
422−
423−-- | escape hatch to define aggregate functions
424−unsafeAggregate1
425− :: ByteString -- ^ aggregate function
426− -> Distinction (Expression outer commons 'Ungrouped schemas params from) x
427− -> Expression outer commons ('Grouped bys) schemas params from y
428−unsafeAggregate1 fun x = UnsafeExpression $ fun <> parenthesized (renderSQL x)
429−
430−unsafeAggregateN
431− :: SOP.SListI xs
432− => ByteString -- ^ function
433− -> Distinction (NP (Expression outer commons 'Ungrouped schemas params from)) xs
434− -> Expression outer commons ('Grouped bys) schemas params from y
435−unsafeAggregateN fun xs = UnsafeExpression $ fun <> parenthesized (renderSQL xs)
436−
437−-- | A type family that calculates `PGSum``PGType` of
438−-- a given argument `PGType`.
439−type family PGSum ty where
440− PGSum 'PGint2 = 'PGint8
441− PGSum 'PGint4 = 'PGint8
442− PGSum 'PGint8 = 'PGnumeric
443− PGSum 'PGfloat4 = 'PGfloat4
444− PGSum 'PGfloat8 = 'PGfloat8
445− PGSum 'PGnumeric = 'PGnumeric
446− PGSum 'PGinterval = 'PGinterval
447− PGSum 'PGmoney = 'PGmoney
448− PGSum pg = TypeError
449− ( 'Text "Squeal type error: Cannot sum with argument type "
450− ':<>: 'ShowType pg )
451−
452−-- | A type family that calculates `PGAvg` type of a `PGType`.
453−type family PGAvg ty where
454− PGAvg 'PGint2 = 'PGnumeric
455− PGAvg 'PGint4 = 'PGnumeric
456− PGAvg 'PGint8 = 'PGnumeric
457− PGAvg 'PGnumeric = 'PGnumeric
458− PGAvg 'PGfloat4 = 'PGfloat8
459− PGAvg 'PGfloat8 = 'PGfloat8
460− PGAvg 'PGinterval = 'PGinterval
461− PGAvg pg = TypeError
462− ('Text "Squeal type error: No average for " ':<>: 'ShowType pg)
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Collection.hsdeleted−169
@@ -1,169 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Collection
3−Description: Array and composite functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Array and composite functions
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DataKinds
14− , FlexibleContexts
15− , FlexibleInstances
16− , MultiParamTypeClasses
17− , OverloadedLabels
18− , OverloadedStrings
19− , RankNTypes
20− , ScopedTypeVariables
21− , TypeApplications
22− , TypeFamilies
23− , TypeOperators
24− , UndecidableInstances
25−#-}
26−
27−module Squeal.PostgreSQL.Expression.Collection
28− ( array
29− , array1
30− , array2
31− , cardinality
32− , index
33− , unnest
34− , row
35− , field
36− ) where
37−
38−import Data.String
39−import Data.Word (Word64)
40−
41−import qualified Generics.SOP as SOP
42−
43−import Squeal.PostgreSQL.Alias
44−import Squeal.PostgreSQL.Expression
45−import Squeal.PostgreSQL.Expression.Set
46−import Squeal.PostgreSQL.List
47−import Squeal.PostgreSQL.Render
48−import Squeal.PostgreSQL.Schema
49−
50−-- $setup
51−-- >>> import Squeal.PostgreSQL
52−
53−-- | >>> printSQL $ array [null_, false, true]
54−-- ARRAY[NULL, FALSE, TRUE]
55−array
56− :: [Expression outer commons grp schemas params from ty]
57− -- ^ array elements
58− -> Expression outer commons grp schemas params from (null ('PGvararray ty))
59−array xs = UnsafeExpression $ "ARRAY" <>
60− bracketed (commaSeparated (renderSQL <$> xs))
61−
62−{- | construct a 1-dimensional fixed length array
63−
64−>>> printSQL $ array1 (null_ :* false *: true)
65−ARRAY[NULL, FALSE, TRUE]
66−
67−>>> :type array1 (null_ :* false *: true)
68−array1 (null_ :* false *: true)
69− :: Expression
70− outer
71− commons
72− grp
73− schemas
74− params
75− from
76− (null ('PGfixarray '[3] ('Null 'PGbool)))
77−-}
78−array1
79− :: (n ~ Length tys, SOP.All ((~) ty) tys)
80− => NP (Expression outer commons grp schemas params from) tys
81− -> Expression outer commons grp schemas params from (null ('PGfixarray '[n] ty))
82−array1 xs = UnsafeExpression $ "ARRAY" <>
83− bracketed (renderCommaSeparated renderSQL xs)
84−
85−{- | construct a 2-dimensional fixed length array
86−
87−>>> printSQL $ array2 ((null_ :* false *: true) *: (false :* null_ *: true))
88−ARRAY[[NULL, FALSE, TRUE], [FALSE, NULL, TRUE]]
89−
90−>>> :type array2 ((null_ :* false *: true) *: (false :* null_ *: true))
91−array2 ((null_ :* false *: true) *: (false :* null_ *: true))
92− :: Expression
93− outer
94− commons
95− grp
96− schemas
97− params
98− from
99− (null ('PGfixarray '[2, 3] ('Null 'PGbool)))
100−-}
101−array2
102− :: ( SOP.All ((~) tys) tyss
103− , SOP.All SOP.SListI tyss
104− , Length tyss ~ n1
105− , SOP.All ((~) ty) tys
106− , Length tys ~ n2 )
107− => NP (NP (Expression outer commons grp schemas params from)) tyss
108− -> Expression outer commons grp schemas params from (null ('PGfixarray '[n1,n2] ty))
109−array2 xss = UnsafeExpression $ "ARRAY" <>
110− bracketed (renderCommaSeparatedConstraint @SOP.SListI (bracketed . renderCommaSeparated renderSQL) xss)
111−
112−-- | >>> printSQL $ cardinality (array [null_, false, true])
113−-- cardinality(ARRAY[NULL, FALSE, TRUE])
114−cardinality :: null ('PGvararray ty) --> null 'PGint8
115−cardinality = unsafeFunction "cardinality"
116−
117−-- | >>> printSQL $ array [null_, false, true] & index 2
118−-- (ARRAY[NULL, FALSE, TRUE])[2]
119−index
120− :: Word64 -- ^ index
121− -> null ('PGvararray ty) --> NullifyType ty
122−index n expr = UnsafeExpression $
123− parenthesized (renderSQL expr) <> "[" <> fromString (show n) <> "]"
124−
125−-- | Expand an array to a set of rows
126−unnest :: SetFunction "unnest" (null ('PGvararray ty)) '["unnest" ::: ty]
127−unnest = unsafeSetFunction
128−
129−-- | A row constructor is an expression that builds a row value
130−-- (also called a composite value) using values for its member fields.
131−--
132−-- >>> :{
133−-- type Complex = 'PGcomposite
134−-- '[ "real" ::: 'NotNull 'PGfloat8
135−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]
136−-- :}
137−--
138−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer commons grp schemas params from ('NotNull Complex)
139−-- >>> printSQL i
140−-- ROW(0, 1)
141−row
142− :: SOP.SListI row
143− => NP (Aliased (Expression outer commons grp schemas params from)) row
144− -- ^ zero or more expressions for the row field values
145− -> Expression outer commons grp schemas params from (null ('PGcomposite row))
146−row exprs = UnsafeExpression $ "ROW" <> parenthesized
147− (renderCommaSeparated (\ (expr `As` _) -> renderSQL expr) exprs)
148−
149−-- | >>> :{
150−-- type Complex = 'PGcomposite
151−-- '[ "real" ::: 'NotNull 'PGfloat8
152−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]
153−-- type Schema = '["complex" ::: 'Typedef Complex]
154−-- :}
155−--
156−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer '[] grp (Public Schema) from params ('NotNull Complex)
157−-- >>> printSQL $ i & field #complex #imaginary
158−-- (ROW(0, 1)::"complex")."imaginary"
159−field
160− :: ( Has sch schemas schema
161− , Has tydef schema ('Typedef ('PGcomposite row))
162− , Has field row ty)
163− => QualifiedAlias sch tydef -- ^ row type
164− -> Alias field -- ^ field name
165− -> Expression outer commons grp schemas params from ('NotNull ('PGcomposite row))
166− -> Expression outer commons grp schemas params from ty
167−field td fld expr = UnsafeExpression $
168− parenthesized (renderSQL expr <> "::" <> renderSQL td)
169− <> "." <> renderSQL fld
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Comparison.hsdeleted−206
@@ -1,206 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Comparison
3−Description: Comparison expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Comparison functions and operators
9−-}
10−
11−{-# LANGUAGE
12− OverloadedStrings
13− , RankNTypes
14− , TypeInType
15− , TypeOperators
16−#-}
17−
18−module Squeal.PostgreSQL.Expression.Comparison
19− ( (.==)
20− , (./=)
21− , (.>=)
22− , (.<)
23− , (.<=)
24− , (.>)
25− , greatest
26− , least
27− , BetweenExpr
28− , between
29− , notBetween
30− , betweenSymmetric
31− , notBetweenSymmetric
32− , isDistinctFrom
33− , isNotDistinctFrom
34− , isTrue
35− , isNotTrue
36− , isFalse
37− , isNotFalse
38− , isUnknown
39− , isNotUnknown
40− ) where
41−
42−import Data.ByteString
43−
44−import Squeal.PostgreSQL.Expression
45−import Squeal.PostgreSQL.Expression.Logic
46−import Squeal.PostgreSQL.Render
47−import Squeal.PostgreSQL.Schema
48−
49−-- $setup
50−-- >>> import Squeal.PostgreSQL
51−
52−-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`
53−-- will produce @NULL@s if one of their arguments is @NULL@.
54−--
55−-- >>> printSQL $ true .== null_
56−-- (TRUE = NULL)
57−(.==) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
58−(.==) = unsafeBinaryOp "="
59−infix 4 .==
60−
61−-- | >>> printSQL $ true ./= null_
62−-- (TRUE <> NULL)
63−(./=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
64−(./=) = unsafeBinaryOp "<>"
65−infix 4 ./=
66−
67−-- | >>> printSQL $ true .>= null_
68−-- (TRUE >= NULL)
69−(.>=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
70−(.>=) = unsafeBinaryOp ">="
71−infix 4 .>=
72−
73−-- | >>> printSQL $ true .< null_
74−-- (TRUE < NULL)
75−(.<) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
76−(.<) = unsafeBinaryOp "<"
77−infix 4 .<
78−
79−-- | >>> printSQL $ true .<= null_
80−-- (TRUE <= NULL)
81−(.<=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
82−(.<=) = unsafeBinaryOp "<="
83−infix 4 .<=
84−
85−-- | >>> printSQL $ true .> null_
86−-- (TRUE > NULL)
87−(.>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
88−(.>) = unsafeBinaryOp ">"
89−infix 4 .>
90−
91−-- | >>> let expr = greatest [param @1] currentTimestamp :: Expression outer commons grp schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)
92−-- >>> printSQL expr
93−-- GREATEST(($1 :: timestamp with time zone), CURRENT_TIMESTAMP)
94−greatest :: FunctionVar ty ty ty
95−greatest = unsafeFunctionVar "GREATEST"
96−
97−-- | >>> printSQL $ least [null_] currentTimestamp
98−-- LEAST(NULL, CURRENT_TIMESTAMP)
99−least :: FunctionVar ty ty ty
100−least = unsafeFunctionVar "LEAST"
101−
102−{- |
103−A @RankNType@ for comparison expressions like `between`.
104−-}
105−type BetweenExpr
106− = forall outer commons grp schemas params from ty
107− . Expression outer commons grp schemas params from ty
108− -> ( Expression outer commons grp schemas params from ty
109− , Expression outer commons grp schemas params from ty ) -- ^ bounds
110− -> Condition outer commons grp schemas params from
111−
112−unsafeBetweenExpr :: ByteString -> BetweenExpr
113−unsafeBetweenExpr fun a (x,y) = UnsafeExpression $
114− renderSQL a <+> fun <+> renderSQL x <+> "AND" <+> renderSQL y
115−
116−{- | >>> printSQL $ true `between` (null_, false)
117−TRUE BETWEEN NULL AND FALSE
118−-}
119−between :: BetweenExpr
120−between = unsafeBetweenExpr "BETWEEN"
121−
122−{- | >>> printSQL $ true `notBetween` (null_, false)
123−TRUE NOT BETWEEN NULL AND FALSE
124−-}
125−notBetween :: BetweenExpr
126−notBetween = unsafeBetweenExpr "NOT BETWEEN"
127−
128−{- | between, after sorting the comparison values
129−
130−>>> printSQL $ true `betweenSymmetric` (null_, false)
131−TRUE BETWEEN SYMMETRIC NULL AND FALSE
132−-}
133−betweenSymmetric :: BetweenExpr
134−betweenSymmetric = unsafeBetweenExpr "BETWEEN SYMMETRIC"
135−
136−{- | not between, after sorting the comparison values
137−
138−>>> printSQL $ true `notBetweenSymmetric` (null_, false)
139−TRUE NOT BETWEEN SYMMETRIC NULL AND FALSE
140−-}
141−notBetweenSymmetric :: BetweenExpr
142−notBetweenSymmetric = unsafeBetweenExpr "NOT BETWEEN SYMMETRIC"
143−
144−{- | not equal, treating null like an ordinary value
145−
146−>>> printSQL $ true `isDistinctFrom` null_
147−(TRUE IS DISTINCT FROM NULL)
148−-}
149−isDistinctFrom :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
150−isDistinctFrom = unsafeBinaryOp "IS DISTINCT FROM"
151−
152−{- | equal, treating null like an ordinary value
153−
154−>>> printSQL $ true `isNotDistinctFrom` null_
155−(TRUE IS NOT DISTINCT FROM NULL)
156−-}
157−isNotDistinctFrom :: Operator (null0 ty) (null1 ty) ('NotNull 'PGbool)
158−isNotDistinctFrom = unsafeBinaryOp "IS NOT DISTINCT FROM"
159−
160−{- | is true
161−
162−>>> printSQL $ true & isTrue
163−(TRUE IS TRUE)
164−-}
165−isTrue :: null0 'PGbool --> null1 'PGbool
166−isTrue = unsafeRightOp "IS TRUE"
167−
168−{- | is false or unknown
169−
170−>>> printSQL $ true & isNotTrue
171−(TRUE IS NOT TRUE)
172−-}
173−isNotTrue :: null0 'PGbool --> null1 'PGbool
174−isNotTrue = unsafeRightOp "IS NOT TRUE"
175−
176−{- | is false
177−
178−>>> printSQL $ true & isFalse
179−(TRUE IS FALSE)
180−-}
181−isFalse :: null0 'PGbool --> null1 'PGbool
182−isFalse = unsafeRightOp "IS FALSE"
183−
184−{- | is true or unknown
185−
186−>>> printSQL $ true & isNotFalse
187−(TRUE IS NOT FALSE)
188−-}
189−isNotFalse :: null0 'PGbool --> null1 'PGbool
190−isNotFalse = unsafeRightOp "IS NOT FALSE"
191−
192−{- | is unknown
193−
194−>>> printSQL $ true & isUnknown
195−(TRUE IS UNKNOWN)
196−-}
197−isUnknown :: null0 'PGbool --> null1 'PGbool
198−isUnknown = unsafeRightOp "IS UNKNOWN"
199−
200−{- | is true or false
201−
202−>>> printSQL $ true & isNotUnknown
203−(TRUE IS NOT UNKNOWN)
204−-}
205−isNotUnknown :: null0 'PGbool --> null1 'PGbool
206−isNotUnknown = unsafeRightOp "IS NOT UNKNOWN"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Json.hsdeleted−462
@@ -1,462 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Json
3−Description: Json and Jsonb functions and operators
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Json and Jsonb functions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , FlexibleContexts
14− , FlexibleInstances
15− , GADTs
16− , OverloadedLabels
17− , OverloadedStrings
18− , PolyKinds
19− , RankNTypes
20− , ScopedTypeVariables
21− , TypeApplications
22− , TypeOperators
23− , UndecidableInstances
24− , UndecidableSuperClasses
25−#-}
26−
27−module Squeal.PostgreSQL.Expression.Json
28− ( -- * Json and Jsonb operators
29− (.->)
30− , (.->>)
31− , (.#>)
32− , (.#>>)
33− -- * Jsonb operators
34− , (.?)
35− , (.?|)
36− , (.?&)
37− , (.-.)
38− , (#-.)
39− -- * Json and Jsonb functions
40− , toJson
41− , toJsonb
42− , arrayToJson
43− , rowToJson
44− , jsonBuildArray
45− , jsonbBuildArray
46− , JsonBuildObject (..)
47− , jsonObject
48− , jsonbObject
49− , jsonZipObject
50− , jsonbZipObject
51− , jsonArrayLength
52− , jsonbArrayLength
53− , jsonTypeof
54− , jsonbTypeof
55− , jsonStripNulls
56− , jsonbStripNulls
57− , jsonbSet
58− , jsonbInsert
59− , jsonbPretty
60− -- * Json and Jsonb set returning functions
61− , jsonEach
62− , jsonbEach
63− , jsonEachText
64− , jsonbEachText
65− , jsonObjectKeys
66− , jsonbObjectKeys
67− , JsonPopulateFunction
68− , jsonPopulateRecord
69− , jsonbPopulateRecord
70− , jsonPopulateRecordSet
71− , jsonbPopulateRecordSet
72− , JsonToRecordFunction
73− , jsonToRecord
74− , jsonbToRecord
75− , jsonToRecordSet
76− , jsonbToRecordSet
77− ) where
78−
79−import Data.ByteString (ByteString)
80−import GHC.TypeLits
81−
82−import Squeal.PostgreSQL.Alias
83−import Squeal.PostgreSQL.Expression
84−import Squeal.PostgreSQL.Expression.Set
85−import Squeal.PostgreSQL.Expression.Type
86−import Squeal.PostgreSQL.List
87−import Squeal.PostgreSQL.Query
88−import Squeal.PostgreSQL.Render
89−import Squeal.PostgreSQL.Schema
90−
91−import qualified Generics.SOP as SOP
92−
93−-- $setup
94−-- >>> import Squeal.PostgreSQL
95−-- >>> import Data.Aeson
96−
97−{-----------------------------------------
98− -- json and jsonb support
99−
100−See https://www.postgresql.org/docs/10/static/functions-json.html -- most
101−comments lifted directly from this page.
102−
103−Table 9.44: json and jsonb operators
104−-----------------------------------------}
105−
106−-- | Get JSON value (object field or array element) at a key.
107−(.->)
108− :: (json `In` PGJsonType, key `In` PGJsonKey)
109− => Operator (null json) (null key) ('Null json)
110−infixl 8 .->
111−(.->) = unsafeBinaryOp "->"
112−
113−-- | Get JSON value (object field or array element) at a key, as text.
114−(.->>)
115− :: (json `In` PGJsonType, key `In` PGJsonKey)
116− => Operator (null json) (null key) ('Null 'PGtext)
117−infixl 8 .->>
118−(.->>) = unsafeBinaryOp "->>"
119−
120−-- | Get JSON value at a specified path.
121−(.#>)
122− :: json `In` PGJsonType
123− => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null json)
124−infixl 8 .#>
125−(.#>) = unsafeBinaryOp "#>"
126−
127−-- | Get JSON value at a specified path as text.
128−(.#>>)
129− :: json `In` PGJsonType
130− => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null 'PGtext)
131−infixl 8 .#>>
132−(.#>>) = unsafeBinaryOp "#>>"
133−
134−-- Additional jsonb operators
135−
136−-- | Does the string exist as a top-level key within the JSON value?
137−(.?) :: Operator (null 'PGjsonb) (null 'PGtext) ('Null 'PGbool)
138−infixl 9 .?
139−(.?) = unsafeBinaryOp "?"
140−
141−-- | Do any of these array strings exist as top-level keys?
142−(.?|) :: Operator
143− (null 'PGjsonb)
144− (null ('PGvararray ('NotNull 'PGtext)))
145− ('Null 'PGbool)
146−infixl 9 .?|
147−(.?|) = unsafeBinaryOp "?|"
148−
149−-- | Do all of these array strings exist as top-level keys?
150−(.?&) :: Operator
151− (null 'PGjsonb)
152− (null ('PGvararray ('NotNull 'PGtext)))
153− ('Null 'PGbool)
154−infixl 9 .?&
155−(.?&) = unsafeBinaryOp "?&"
156−
157−-- | Delete a key or keys from a JSON object, or remove an array element.
158−--
159−-- If the right operand is
160−--
161−-- @ text @: Delete key / value pair or string element from left operand.
162−-- Key / value pairs are matched based on their key value,
163−--
164−-- @ text[] @: Delete multiple key / value pairs or string elements
165−-- from left operand. Key / value pairs are matched based on their key value,
166−--
167−-- @ integer @: Delete the array element with specified index (Negative integers
168−-- count from the end). Throws an error if top level container is not an array.
169−(.-.)
170− :: key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]
171− => Operator (null 'PGjsonb) (null key) (null 'PGjsonb)
172−infixl 6 .-.
173−(.-.) = unsafeBinaryOp "-"
174−
175−-- | Delete the field or element with specified path (for JSON arrays, negative
176−-- integers count from the end)
177−(#-.) :: Operator (null 'PGjsonb) (null ('PGvararray ('NotNull 'PGtext))) (null 'PGjsonb)
178−infixl 6 #-.
179−(#-.) = unsafeBinaryOp "#-"
180−
181−{-----------------------------------------
182−Table 9.45: JSON creation functions
183−-----------------------------------------}
184−
185−-- | Returns the value as json. Arrays and composites are converted
186−-- (recursively) to arrays and objects; otherwise, if there is a cast from the
187−-- type to json, the cast function will be used to perform the conversion;
188−-- otherwise, a scalar value is produced. For any scalar type other than a
189−-- number, a Boolean, or a null value, the text representation will be used, in
190−-- such a fashion that it is a valid json value.
191−toJson :: null ty --> null 'PGjson
192−toJson = unsafeFunction "to_json"
193−
194−-- | Returns the value as jsonb. Arrays and composites are converted
195−-- (recursively) to arrays and objects; otherwise, if there is a cast from the
196−-- type to json, the cast function will be used to perform the conversion;
197−-- otherwise, a scalar value is produced. For any scalar type other than a
198−-- number, a Boolean, or a null value, the text representation will be used, in
199−-- such a fashion that it is a valid jsonb value.
200−toJsonb :: null ty --> null 'PGjsonb
201−toJsonb = unsafeFunction "to_jsonb"
202−
203−-- | Returns the array as a JSON array. A PostgreSQL multidimensional array
204−-- becomes a JSON array of arrays.
205−arrayToJson :: null ('PGvararray ty) --> null 'PGjson
206−arrayToJson = unsafeFunction "array_to_json"
207−
208−-- | Returns the row as a JSON object.
209−rowToJson :: null ('PGcomposite ty) --> null 'PGjson
210−rowToJson = unsafeFunction "row_to_json"
211−
212−-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic
213−-- argument list.
214−jsonBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjson
215−jsonBuildArray = unsafeFunctionN "json_build_array"
216−
217−-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a
218−-- variadic argument list.
219−jsonbBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjsonb
220−jsonbBuildArray = unsafeFunctionN "jsonb_build_array"
221−
222−-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic
223−-- argument list. The elements of the argument list must alternate between text
224−-- and values.
225−class SOP.SListI tys => JsonBuildObject tys where
226−
227− jsonBuildObject :: tys ---> null 'PGjson
228− jsonBuildObject = unsafeFunctionN "json_build_object"
229−
230− jsonbBuildObject :: tys ---> null 'PGjsonb
231− jsonbBuildObject = unsafeFunctionN "jsonb_build_object"
232−
233−instance JsonBuildObject '[]
234−instance (JsonBuildObject tys, key `In` PGJsonKey)
235− => JsonBuildObject ('NotNull key ': value ': tys)
236−
237−-- | Builds a JSON object out of a text array.
238−-- The array must have two dimensions
239−-- such that each inner array has exactly two elements,
240−-- which are taken as a key/value pair.
241−jsonObject
242− :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))
243− --> null 'PGjson
244−jsonObject = unsafeFunction "json_object"
245−
246−-- | Builds a binary JSON object out of a text array.
247−-- The array must have two dimensions
248−-- such that each inner array has exactly two elements,
249−-- which are taken as a key/value pair.
250−jsonbObject
251− :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))
252− --> null 'PGjsonb
253−jsonbObject = unsafeFunction "jsonb_object"
254−
255−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
256−-- keys and one for values, that are zipped pairwise to create a JSON object.
257−jsonZipObject ::
258− '[ null ('PGvararray ('NotNull 'PGtext))
259− , null ('PGvararray ('NotNull 'PGtext)) ]
260− ---> null 'PGjson
261−jsonZipObject = unsafeFunctionN "json_object"
262−
263−-- | This is an alternate form of 'jsonbObject' that takes two arrays; one for
264−-- keys and one for values, that are zipped pairwise to create a binary JSON
265−-- object.
266−jsonbZipObject ::
267− '[ null ('PGvararray ('NotNull 'PGtext))
268− , null ('PGvararray ('NotNull 'PGtext)) ]
269− ---> null 'PGjsonb
270−jsonbZipObject = unsafeFunctionN "jsonb_object"
271−
272−{-----------------------------------------
273−Table 9.46: JSON processing functions
274−-----------------------------------------}
275−
276−-- | Returns the number of elements in the outermost JSON array.
277−jsonArrayLength :: null 'PGjson --> null 'PGint4
278−jsonArrayLength = unsafeFunction "json_array_length"
279−
280−-- | Returns the number of elements in the outermost binary JSON array.
281−jsonbArrayLength :: null 'PGjsonb --> null 'PGint4
282−jsonbArrayLength = unsafeFunction "jsonb_array_length"
283−
284−-- | Returns the type of the outermost JSON value as a text string. Possible
285−-- types are object, array, string, number, boolean, and null.
286−jsonTypeof :: null 'PGjson --> null 'PGtext
287−jsonTypeof = unsafeFunction "json_typeof"
288−
289−-- | Returns the type of the outermost binary JSON value as a text string.
290−-- Possible types are object, array, string, number, boolean, and null.
291−jsonbTypeof :: null 'PGjsonb --> null 'PGtext
292−jsonbTypeof = unsafeFunction "jsonb_typeof"
293−
294−-- | Returns its argument with all object fields that have null values omitted.
295−-- Other null values are untouched.
296−jsonStripNulls :: null 'PGjson --> null 'PGjson
297−jsonStripNulls = unsafeFunction "json_strip_nulls"
298−
299−-- | Returns its argument with all object fields that have null values omitted.
300−-- Other null values are untouched.
301−jsonbStripNulls :: null 'PGjsonb --> null 'PGjsonb
302−jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"
303−
304−-- | @ jsonbSet target path new_value create_missing @
305−--
306−-- Returns target with the section designated by path replaced by @new_value@,
307−-- or with @new_value@ added if create_missing is
308−-- `Squeal.PostgreSQL.Expression.Logic.true` and the
309−-- item designated by path does not exist. As with the path orientated
310−-- operators, negative integers that appear in path count from the end of JSON
311−-- arrays.
312−jsonbSet ::
313− '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))
314− , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb
315−jsonbSet = unsafeFunctionN "jsonbSet"
316−
317−-- | @ jsonbInsert target path new_value insert_after @
318−--
319−-- Returns target with @new_value@ inserted. If target section designated by
320−-- path is in a JSONB array, @new_value@ will be inserted before target or after
321−-- if @insert_after@ is `Squeal.PostgreSQL.Expression.Logic.true`.
322−-- If target section designated by
323−-- path is in JSONB object, @new_value@ will be inserted only if target does not
324−-- exist. As with the path orientated operators, negative integers that appear
325−-- in path count from the end of JSON arrays.
326−jsonbInsert ::
327− '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))
328− , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb
329−jsonbInsert = unsafeFunctionN "jsonb_insert"
330−
331−-- | Returns its argument as indented JSON text.
332−jsonbPretty :: null 'PGjsonb --> null 'PGtext
333−jsonbPretty = unsafeFunction "jsonb_pretty"
334−
335−{- | Expands the outermost JSON object into a set of key/value pairs.
336−
337−>>> printSQL (select Star (from (jsonEach (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))
338−SELECT * FROM json_each(('{"a":"foo","b":"bar"}' :: json))
339−-}
340−jsonEach :: SetFunction "json_each" (null 'PGjson)
341− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]
342−jsonEach = unsafeSetFunction
343−
344−{- | Expands the outermost binary JSON object into a set of key/value pairs.
345−
346−>>> printSQL (select Star (from (jsonbEach (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))
347−SELECT * FROM jsonb_each(('{"a":"foo","b":"bar"}' :: jsonb))
348−-}
349−jsonbEach
350− :: SetFunction "jsonb_each" (nullity 'PGjsonb)
351− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]
352−jsonbEach = unsafeSetFunction
353−
354−{- | Expands the outermost JSON object into a set of key/value pairs.
355−
356−>>> printSQL (select Star (from (jsonEachText (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))
357−SELECT * FROM json_each_text(('{"a":"foo","b":"bar"}' :: json))
358−-}
359−jsonEachText
360− :: SetFunction "json_each_text" (null 'PGjson)
361− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]
362−jsonEachText = unsafeSetFunction
363−
364−{- | Expands the outermost binary JSON object into a set of key/value pairs.
365−
366−>>> printSQL (select Star (from (jsonbEachText (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))
367−SELECT * FROM jsonb_each_text(('{"a":"foo","b":"bar"}' :: jsonb))
368−-}
369−jsonbEachText
370− :: SetFunction "jsonb_each_text" (null 'PGjsonb)
371− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]
372−jsonbEachText = unsafeSetFunction
373−
374−{- | Returns set of keys in the outermost JSON object.
375−
376−>>> printSQL (jsonObjectKeys (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))
377−json_object_keys(('{"a":"foo","b":"bar"}' :: json))
378−-}
379−jsonObjectKeys
380− :: SetFunction "json_object_keys" (nullity 'PGjson)
381− '["json_object_keys" ::: 'NotNull 'PGtext]
382−jsonObjectKeys = unsafeSetFunction
383−
384−{- | Returns set of keys in the outermost JSON object.
385−
386−>>> printSQL (jsonbObjectKeys (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))
387−jsonb_object_keys(('{"a":"foo","b":"bar"}' :: jsonb))
388−-}
389−jsonbObjectKeys
390− :: SetFunction "jsonb_object_keys" (null 'PGjsonb)
391− '["jsonb_object_keys" ::: 'NotNull 'PGtext]
392−jsonbObjectKeys = unsafeSetFunction
393−
394−-- | Build rows from Json types.
395−type JsonPopulateFunction fun json
396− = forall schemas row outer commons params
397− . json `In` PGJsonType
398− => TypeExpression schemas ('NotNull ('PGcomposite row)) -- ^ row type
399− -> Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)
400− -- ^ json type
401− -> FromClause outer commons schemas params '[fun ::: row]
402−
403−unsafePopulateFunction
404− :: forall fun ty
405− . KnownSymbol fun => Alias fun -> JsonPopulateFunction fun ty
406−unsafePopulateFunction _fun ty expr = UnsafeFromClause $ renderSymbol @fun
407− <> parenthesized ("null::" <> renderSQL ty <> ", " <> renderSQL expr)
408−
409−-- | Expands the JSON expression to a row whose columns match the record
410−-- type defined by the given table.
411−jsonPopulateRecord :: JsonPopulateFunction "json_populate_record" 'PGjson
412−jsonPopulateRecord = unsafePopulateFunction #json_populate_record
413−
414−-- | Expands the binary JSON expression to a row whose columns match the record
415−-- type defined by the given table.
416−jsonbPopulateRecord :: JsonPopulateFunction "jsonb_populate_record" 'PGjsonb
417−jsonbPopulateRecord = unsafePopulateFunction #jsonb_populate_record
418−
419−-- | Expands the outermost array of objects in the given JSON expression to a
420−-- set of rows whose columns match the record type defined by the given table.
421−jsonPopulateRecordSet :: JsonPopulateFunction "json_populate_record_set" 'PGjson
422−jsonPopulateRecordSet = unsafePopulateFunction #json_populate_record_set
423−
424−-- | Expands the outermost array of objects in the given binary JSON expression
425−-- to a set of rows whose columns match the record type defined by the given
426−-- table.
427−jsonbPopulateRecordSet :: JsonPopulateFunction "jsonb_populate_record_set" 'PGjsonb
428−jsonbPopulateRecordSet = unsafePopulateFunction #jsonb_populate_record_set
429−
430−-- | Build rows from Json types.
431−type JsonToRecordFunction json
432− = forall outer commons schemas params tab row
433− . (SOP.SListI row, json `In` PGJsonType)
434− => Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)
435− -- ^ json type
436− -> Aliased (NP (Aliased (TypeExpression schemas))) (tab ::: row)
437− -- ^ row type
438− -> FromClause outer commons schemas params '[tab ::: row]
439−
440−unsafeRecordFunction :: ByteString -> JsonToRecordFunction json
441−unsafeRecordFunction fun expr (types `As` tab) = UnsafeFromClause $
442− fun <> parenthesized (renderSQL expr) <+> "AS" <+> renderSQL tab
443− <> parenthesized (renderCommaSeparated renderTy types)
444− where
445− renderTy :: Aliased (TypeExpression schemas) ty -> ByteString
446− renderTy (ty `As` alias) = renderSQL alias <+> renderSQL ty
447−
448−-- | Builds an arbitrary record from a JSON object.
449−jsonToRecord :: JsonToRecordFunction 'PGjson
450−jsonToRecord = unsafeRecordFunction "json_to_record"
451−
452−-- | Builds an arbitrary record from a binary JSON object.
453−jsonbToRecord :: JsonToRecordFunction 'PGjsonb
454−jsonbToRecord = unsafeRecordFunction "jsonb_to_record"
455−
456−-- | Builds an arbitrary set of records from a JSON array of objects.
457−jsonToRecordSet :: JsonToRecordFunction 'PGjson
458−jsonToRecordSet = unsafeRecordFunction "json_to_record_set"
459−
460−-- | Builds an arbitrary set of records from a binary JSON array of objects.
461−jsonbToRecordSet :: JsonToRecordFunction 'PGjsonb
462−jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Literal.hsdeleted−87
@@ -1,87 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Literal
3−Description: Literal expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Literal expressions
9−-}
10−
11−{-# LANGUAGE
12− FlexibleContexts
13− , FlexibleInstances
14− , LambdaCase
15− , OverloadedStrings
16− , RankNTypes
17− , ScopedTypeVariables
18− , TypeApplications
19− , TypeSynonymInstances
20− , UndecidableInstances
21−#-}
22−
23−module Squeal.PostgreSQL.Expression.Literal (Literal (..)) where
24−
25−import ByteString.StrictBuilder (builderBytes)
26−import Data.ByteString.Lazy (toStrict)
27−import Data.Int
28−import Data.String
29−import Data.Text (Text)
30−
31−import qualified Data.Aeson as JSON
32−import qualified Data.Text as Text
33−import qualified Data.Text.Lazy as Lazy (Text)
34−import qualified Data.Text.Lazy as Lazy.Text
35−
36−import Squeal.PostgreSQL.Binary
37−import Squeal.PostgreSQL.Expression
38−import Squeal.PostgreSQL.Expression.Logic
39−import Squeal.PostgreSQL.PG
40−import Squeal.PostgreSQL.Render
41−
42−{- |
43−The `Literal` class allows embedding a Haskell value directly
44−as an `Expression` using `literal`.
45−
46−>>> printSQL (literal 'a')
47−E'a'
48−
49−>>> printSQL (literal (1 :: Double))
50−1.0
51−
52−>>> printSQL (literal (Json [1 :: Double, 2]))
53−('[1.0,2.0]' :: json)
54−
55−>>> printSQL (literal (Enumerated GT))
56−'GT'
57−-}
58−class Literal hask where literal :: hask -> Expr (null (PG hask))
59−instance Literal Bool where
60− literal = \case
61− True -> true
62− False -> false
63−instance JSON.ToJSON hask => Literal (Json hask) where
64− literal = UnsafeExpression . parenthesized . (<> " :: json")
65− . singleQuotedUtf8 . toStrict . JSON.encode . getJson
66−instance JSON.ToJSON hask => Literal (Jsonb hask) where
67− literal = UnsafeExpression . parenthesized . (<> " :: jsonb")
68− . singleQuotedUtf8 . toStrict . JSON.encode . getJsonb
69−instance Literal Char where
70− literal chr = UnsafeExpression $
71− "E\'" <> fromString (escape chr) <> "\'"
72−instance Literal String where literal = fromString
73−instance Literal Int16 where literal = fromIntegral
74−instance Literal Int32 where literal = fromIntegral
75−instance Literal Int64 where literal = fromIntegral
76−instance Literal Float where literal = fromRational . toRational
77−instance Literal Double where literal = fromRational . toRational
78−instance Literal Text where literal = fromString . Text.unpack
79−instance Literal Lazy.Text where literal = fromString . Lazy.Text.unpack
80−instance ToParam (Enumerated enum) (PG (Enumerated enum))
81− => Literal (Enumerated enum) where
82− literal
83− = UnsafeExpression
84− . singleQuotedUtf8
85− . builderBytes
86− . unK
87− . toParam @(Enumerated enum) @(PG (Enumerated enum))
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Logic.hsdeleted−105
@@ -1,105 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Logic
3−Description: Logical expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Logical expressions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , TypeOperators
15−#-}
16−
17−module Squeal.PostgreSQL.Expression.Logic
18− ( Condition
19− , true
20− , false
21− , not_
22− , (.&&)
23− , (.||)
24− , caseWhenThenElse
25− , ifThenElse
26− ) where
27−
28−import Squeal.PostgreSQL.Expression
29−import Squeal.PostgreSQL.Render
30−import Squeal.PostgreSQL.Schema
31−
32−-- | A `Condition` is an `Expression`, which can evaluate
33−-- to `true`, `false` or `Squeal.PostgreSQL.Null.null_`. This is because SQL uses
34−-- a three valued logic.
35−type Condition outer commons grp schemas params from =
36− Expression outer commons grp schemas params from ('Null 'PGbool)
37−
38−-- | >>> printSQL true
39−-- TRUE
40−true :: Expr (null 'PGbool)
41−true = UnsafeExpression "TRUE"
42−
43−-- | >>> printSQL false
44−-- FALSE
45−false :: Expr (null 'PGbool)
46−false = UnsafeExpression "FALSE"
47−
48−-- | >>> printSQL $ not_ true
49−-- (NOT TRUE)
50−not_ :: null 'PGbool --> null 'PGbool
51−not_ = unsafeLeftOp "NOT"
52−
53−-- | >>> printSQL $ true .&& false
54−-- (TRUE AND FALSE)
55−(.&&) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)
56−infixr 3 .&&
57−(.&&) = unsafeBinaryOp "AND"
58−
59−-- | >>> printSQL $ true .|| false
60−-- (TRUE OR FALSE)
61−(.||) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)
62−infixr 2 .||
63−(.||) = unsafeBinaryOp "OR"
64−
65−-- | >>> :{
66−-- let
67−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)
68−-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3
69−-- in printSQL expression
70−-- :}
71−-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END
72−caseWhenThenElse
73− :: [ ( Condition outer commons grp schemas params from
74− , Expression outer commons grp schemas params from ty
75− ) ]
76− -- ^ whens and thens
77− -> Expression outer commons grp schemas params from ty
78− -- ^ else
79− -> Expression outer commons grp schemas params from ty
80−caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat
81− [ "CASE"
82− , mconcat
83− [ mconcat
84− [ " WHEN ", renderSQL when_
85− , " THEN ", renderSQL then_
86− ]
87− | (when_,then_) <- whenThens
88− ]
89− , " ELSE ", renderSQL else_
90− , " END"
91− ]
92−
93−-- | >>> :{
94−-- let
95−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)
96−-- expression = ifThenElse true 1 0
97−-- in printSQL expression
98−-- :}
99−-- CASE WHEN TRUE THEN 1 ELSE 0 END
100−ifThenElse
101− :: Condition outer commons grp schemas params from
102− -> Expression outer commons grp schemas params from ty -- ^ then
103− -> Expression outer commons grp schemas params from ty -- ^ else
104− -> Expression outer commons grp schemas params from ty
105−ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Math.hsdeleted−100
@@ -1,100 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Math
3−Description: Math expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Mathematical functions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , TypeOperators
15−#-}
16−
17−module Squeal.PostgreSQL.Expression.Math
18− ( atan2_
19− , quot_
20− , rem_
21− , trunc
22− , round_
23− , ceiling_
24− ) where
25−
26−import Squeal.PostgreSQL.Expression
27−import Squeal.PostgreSQL.List
28−import Squeal.PostgreSQL.Schema
29−
30−-- $setup
31−-- >>> import Squeal.PostgreSQL
32−
33−-- | >>> :{
34−-- let
35−-- expression :: Expr (null 'PGfloat4)
36−-- expression = atan2_ (pi *: 2)
37−-- in printSQL expression
38−-- :}
39−-- atan2(pi(), 2)
40−atan2_ :: float `In` PGFloating => '[ null float, null float] ---> null float
41−atan2_ = unsafeFunctionN "atan2"
42−
43−
44−-- | integer division, truncates the result
45−--
46−-- >>> :{
47−-- let
48−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)
49−-- expression = 5 `quot_` 2
50−-- in printSQL expression
51−-- :}
52−-- (5 / 2)
53−quot_
54− :: int `In` PGIntegral
55− => Operator (null int) (null int) (null int)
56−quot_ = unsafeBinaryOp "/"
57−
58−-- | remainder upon integer division
59−--
60−-- >>> :{
61−-- let
62−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)
63−-- expression = 5 `rem_` 2
64−-- in printSQL expression
65−-- :}
66−-- (5 % 2)
67−rem_
68− :: int `In` PGIntegral
69− => Operator (null int) (null int) (null int)
70−rem_ = unsafeBinaryOp "%"
71−
72−-- | >>> :{
73−-- let
74−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)
75−-- expression = trunc pi
76−-- in printSQL expression
77−-- :}
78−-- trunc(pi())
79−trunc :: frac `In` PGFloating => null frac --> null frac
80−trunc = unsafeFunction "trunc"
81−
82−-- | >>> :{
83−-- let
84−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)
85−-- expression = round_ pi
86−-- in printSQL expression
87−-- :}
88−-- round(pi())
89−round_ :: frac `In` PGFloating => null frac --> null frac
90−round_ = unsafeFunction "round"
91−
92−-- | >>> :{
93−-- let
94−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)
95−-- expression = ceiling_ pi
96−-- in printSQL expression
97−-- :}
98−-- ceiling(pi())
99−ceiling_ :: frac `In` PGFloating => null frac --> null frac
100−ceiling_ = unsafeFunction "ceiling"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Null.hsdeleted−104
@@ -1,104 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Null
3−Description: Null
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Null values and null handling functions
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , TypeOperators
15−#-}
16−
17−module Squeal.PostgreSQL.Expression.Null
18− ( null_
19− , notNull
20− , coalesce
21− , fromNull
22− , isNull
23− , isNotNull
24− , matchNull
25− , nullIf
26− ) where
27−
28−import Squeal.PostgreSQL.Expression
29−import Squeal.PostgreSQL.Expression.Logic
30−import Squeal.PostgreSQL.Render
31−import Squeal.PostgreSQL.Schema
32−
33−-- $setup
34−-- >>> import Squeal.PostgreSQL
35−
36−-- | analagous to `Nothing`
37−--
38−-- >>> printSQL null_
39−-- NULL
40−null_ :: Expr ('Null ty)
41−null_ = UnsafeExpression "NULL"
42−
43−-- | analagous to `Just`
44−--
45−-- >>> printSQL $ notNull true
46−-- TRUE
47−notNull :: 'NotNull ty --> 'Null ty
48−notNull = UnsafeExpression . renderSQL
49−
50−-- | return the leftmost value which is not NULL
51−--
52−-- >>> printSQL $ coalesce [null_, true] false
53−-- COALESCE(NULL, TRUE, FALSE)
54−coalesce :: FunctionVar ('Null ty) ('NotNull ty) ('NotNull ty)
55−coalesce nullxs notNullx = UnsafeExpression $
56− "COALESCE" <> parenthesized (commaSeparated
57− ((renderSQL <$> nullxs) <> [renderSQL notNullx]))
58−
59−-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@
60−--
61−-- >>> printSQL $ fromNull true null_
62−-- COALESCE(NULL, TRUE)
63−fromNull
64− :: Expression outer commons grp schemas params from ('NotNull ty)
65− -- ^ what to convert @NULL@ to
66− -> Expression outer commons grp schemas params from ('Null ty)
67− -> Expression outer commons grp schemas params from ('NotNull ty)
68−fromNull notNullx nullx = coalesce [nullx] notNullx
69−
70−-- | >>> printSQL $ null_ & isNull
71−-- NULL IS NULL
72−isNull :: 'Null ty --> null 'PGbool
73−isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"
74−
75−-- | >>> printSQL $ null_ & isNotNull
76−-- NULL IS NOT NULL
77−isNotNull :: 'Null ty --> null 'PGbool
78−isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"
79−
80−-- | analagous to `maybe` using @IS NULL@
81−--
82−-- >>> printSQL $ matchNull true not_ null_
83−-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END
84−matchNull
85− :: Expression outer commons grp schemas params from (nullty)
86− -- ^ what to convert @NULL@ to
87− -> ( Expression outer commons grp schemas params from ('NotNull ty)
88− -> Expression outer commons grp schemas params from (nullty) )
89− -- ^ function to perform when @NULL@ is absent
90− -> Expression outer commons grp schemas params from ('Null ty)
91− -> Expression outer commons grp schemas params from (nullty)
92−matchNull y f x = ifThenElse (isNull x) y
93− (f (UnsafeExpression (renderSQL x)))
94−
95−{-| right inverse to `fromNull`, if its arguments are equal then
96−`nullIf` gives @NULL@.
97−
98−>>> :set -XTypeApplications -XDataKinds
99−>>> let expr = nullIf (false *: param @1) :: Expression outer commons grp schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)
100−>>> printSQL expr
101−NULLIF(FALSE, ($1 :: bool))
102−-}
103−nullIf :: '[ 'NotNull ty, 'NotNull ty] ---> 'Null ty
104−nullIf = unsafeFunctionN "NULLIF"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Parameter.hsdeleted−80
@@ -1,80 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Parameter
3−Description: Parameters
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Parameters, out-of-line data values
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DataKinds
14− , FlexibleContexts
15− , FlexibleInstances
16− , FunctionalDependencies
17− , KindSignatures
18− , MultiParamTypeClasses
19− , OverloadedStrings
20− , RankNTypes
21− , ScopedTypeVariables
22− , TypeApplications
23− , TypeOperators
24− , UndecidableInstances
25−#-}
26−
27−module Squeal.PostgreSQL.Expression.Parameter
28− ( HasParameter (parameter)
29− , param
30− ) where
31−
32−import GHC.TypeLits
33−
34−import Squeal.PostgreSQL.Expression
35−import Squeal.PostgreSQL.Expression.Type
36−import Squeal.PostgreSQL.Render
37−import Squeal.PostgreSQL.Schema
38−
39−-- $setup
40−-- >>> import Squeal.PostgreSQL
41−
42−{- | A `HasParameter` constraint is used to indicate a value that is
43−supplied externally to a SQL statement.
44−`Squeal.PostgreSQL.PQ.manipulateParams`,
45−`Squeal.PostgreSQL.PQ.queryParams` and
46−`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values
47−separately from the SQL command string, in which case `param`s are used to
48−refer to the out-of-line data values.
49−-}
50−class KnownNat n => HasParameter
51− (n :: Nat)
52− (params :: [NullityType])
53− (ty :: NullityType)
54− | n params -> ty where
55− -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.
56− --
57− -- >>> let expr = parameter @1 int4 :: Expression outer '[] grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)
58− -- >>> printSQL expr
59− -- ($1 :: int4)
60− parameter
61− :: TypeExpression schemas ty
62− -> Expression outer commons grp schemas params from ty
63− parameter ty = UnsafeExpression $ parenthesized $
64− "$" <> renderNat @n <+> "::"
65− <+> renderSQL ty
66−instance {-# OVERLAPPING #-} HasParameter 1 (ty1:tys) ty1
67−instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)
68− => HasParameter n (ty' : params) ty
69−
70−-- | `param` takes a `Nat` using type application and for basic types,
71−-- infers a `TypeExpression`.
72−--
73−-- >>> let expr = param @1 :: Expression outer commons grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)
74−-- >>> printSQL expr
75−-- ($1 :: int4)
76−param
77− :: forall n outer commons schemas params from grp ty
78− . (PGTyped schemas ty, HasParameter n params ty)
79− => Expression outer commons grp schemas params from ty -- ^ param
80−param = parameter @n (pgtype @schemas)
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Range.hsdeleted−230
@@ -1,230 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Range
3−Description: range types and functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Range types and functions
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DataKinds
14− , DeriveAnyClass
15− , DeriveGeneric
16− , DeriveFoldable
17− , DerivingStrategies
18− , DeriveTraversable
19− , FlexibleContexts
20− , FlexibleInstances
21− , LambdaCase
22− , MultiParamTypeClasses
23− , OverloadedLabels
24− , OverloadedStrings
25− , PatternSynonyms
26− , RankNTypes
27− , ScopedTypeVariables
28− , TypeApplications
29− , TypeFamilies
30− , TypeOperators
31− , UndecidableInstances
32−#-}
33−
34−module Squeal.PostgreSQL.Expression.Range
35− ( range
36− , Range (..)
37− , (<=..<=), (<..<), (<=..<), (<..<=)
38− , moreThan, atLeast, lessThan, atMost
39− , singleton, whole
40− , Bound (..)
41− , (.<@)
42− , (@>.)
43− , (<<@)
44− , (@>>)
45− , (&<)
46− , (&>)
47− , (-|-)
48− , (@+)
49− , (@*)
50− , (@-)
51− , lowerBound
52− , upperBound
53− , isEmpty
54− , lowerInc
55− , lowerInf
56− , upperInc
57− , upperInf
58− , rangeMerge
59− ) where
60−
61−import BinaryParser
62−import ByteString.StrictBuilder
63−import Data.Bits
64−import qualified GHC.Generics as GHC
65−import qualified Generics.SOP as SOP
66−import qualified PostgreSQL.Binary.Decoding as Decoding
67−
68−import Squeal.PostgreSQL.Binary
69−import Squeal.PostgreSQL.Expression
70−import Squeal.PostgreSQL.Expression.Type hiding (bool)
71−import Squeal.PostgreSQL.PG
72−import Squeal.PostgreSQL.Render
73−import Squeal.PostgreSQL.Schema
74−
75−-- $setup
76−-- >>> import Squeal.PostgreSQL
77−
78−-- | Construct a `range`
79−--
80−-- >>> printSQL $ range tstzrange (atLeast now)
81−-- tstzrange(now(), NULL, '[)')
82−-- >>> printSQL $ range numrange (0 <=..< 2*pi)
83−-- numrange(0, (2 * pi()), '[)')
84−-- >>> printSQL $ range int4range Empty
85−-- ('empty' :: int4range)
86−range
87− :: TypeExpression schemas (null ('PGrange ty))
88− -> Range (Expression outer commons grp schemas params from ('NotNull ty))
89− -> Expression outer commons grp schemas params from (null ('PGrange ty))
90−range ty = \case
91− Empty -> UnsafeExpression $ parenthesized
92− (emp <+> "::" <+> renderSQL ty)
93− NonEmpty l u -> UnsafeExpression $ renderSQL ty <> parenthesized
94− (commaSeparated (args l u))
95− where
96− emp = singleQuote <> "empty" <> singleQuote
97− args l u = [arg l, arg u, singleQuote <> bra l <> ket u <> singleQuote]
98− singleQuote = "\'"
99− arg = \case
100− Infinite -> "NULL"; Closed x -> renderSQL x; Open x -> renderSQL x
101− bra = \case Infinite -> "("; Closed _ -> "["; Open _ -> "("
102− ket = \case Infinite -> ")"; Closed _ -> "]"; Open _ -> ")"
103−
104−data Bound x = Infinite | Closed x | Open x
105− deriving
106− ( Eq, Ord, Show, Read, GHC.Generic
107− , Functor, Foldable, Traversable )
108−
109−data Range x = Empty | NonEmpty (Bound x) (Bound x)
110− deriving
111− ( Eq, Ord, Show, Read, GHC.Generic
112− , Functor, Foldable, Traversable )
113− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)
114−type instance PG (Range x) = 'PGrange (PG x)
115−instance ToParam x pg => ToParam (Range x) ('PGrange pg) where
116− toParam rng = K $
117− word8 (setFlags rng 0) <>
118− case rng of
119− Empty -> mempty
120− NonEmpty lower upper -> putBound lower <> putBound upper
121− where
122− putBound = \case
123− Infinite -> mempty
124− Closed value -> putValue (unK (toParam @x @pg value))
125− Open value -> putValue (unK (toParam @x @pg value))
126− putValue value = int32BE (fromIntegral (builderLength value)) <> value
127− setFlags = \case
128− Empty -> (`setBit` 0)
129− NonEmpty lower upper ->
130− setLowerFlags lower . setUpperFlags upper
131− setLowerFlags = \case
132− Infinite -> (`setBit` 3)
133− Closed _ -> (`setBit` 1)
134− Open _ -> id
135− setUpperFlags = \case
136− Infinite -> (`setBit` 4)
137− Closed _ -> (`setBit` 2)
138− Open _ -> id
139−instance FromValue pg y => FromValue ('PGrange pg) (Range y) where
140− fromValue = do
141− flag <- byte
142− if testBit flag 0 then return Empty else do
143− lower <-
144− if testBit flag 3
145− then return Infinite
146− else do
147− len <- sized 4 Decoding.int
148− l <- sized len (fromValue @pg)
149− return $ if testBit flag 1 then Closed l else Open l
150− upper <-
151− if testBit flag 4
152− then return Infinite
153− else do
154− len <- sized 4 Decoding.int
155− l <- sized len (fromValue @pg)
156− return $ if testBit flag 2 then Closed l else Open l
157− return $ NonEmpty lower upper
158−
159−(<=..<=), (<..<), (<=..<), (<..<=) :: x -> x -> Range x
160−infix 4 <=..<=, <..<, <=..<, <..<=
161−x <=..<= y = NonEmpty (Closed x) (Closed y)
162−x <..< y = NonEmpty (Open x) (Open y)
163−x <=..< y = NonEmpty (Closed x) (Open y)
164−x <..<= y = NonEmpty (Open x) (Closed y)
165−
166−moreThan, atLeast, lessThan, atMost :: x -> Range x
167−moreThan x = NonEmpty (Open x) Infinite
168−atLeast x = NonEmpty (Closed x) Infinite
169−lessThan x = NonEmpty Infinite (Open x)
170−atMost x = NonEmpty Infinite (Closed x)
171−
172−singleton :: x -> Range x
173−singleton x = x <=..<= x
174−
175−whole :: Range x
176−whole = NonEmpty Infinite Infinite
177−
178−(.<@) :: Operator ('NotNull ty) (null ('PGrange ty)) ('Null 'PGbool)
179−(.<@) = unsafeBinaryOp "<@"
180−
181−(@>.) :: Operator (null ('PGrange ty)) ('NotNull ty) ('Null 'PGbool)
182−(@>.) = unsafeBinaryOp "<@"
183−
184−(<<@) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)
185−(<<@) = unsafeBinaryOp "<<"
186−
187−(@>>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)
188−(@>>) = unsafeBinaryOp ">>"
189−
190−(&<) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)
191−(&<) = unsafeBinaryOp "&<"
192−
193−(&>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)
194−(&>) = unsafeBinaryOp "&>"
195−
196−(-|-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)
197−(-|-) = unsafeBinaryOp "-|-"
198−
199−(@+) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))
200−(@+) = unsafeBinaryOp "+"
201−
202−(@*) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))
203−(@*) = unsafeBinaryOp "*"
204−
205−(@-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))
206−(@-) = unsafeBinaryOp "-"
207−
208−lowerBound :: null ('PGrange ty) --> 'Null ty
209−lowerBound = unsafeFunction "lower"
210−
211−upperBound :: null ('PGrange ty) --> 'Null ty
212−upperBound = unsafeFunction "upper"
213−
214−isEmpty :: null ('PGrange ty) --> 'Null 'PGbool
215−isEmpty = unsafeFunction "isempty"
216−
217−lowerInc :: null ('PGrange ty) --> 'Null 'PGbool
218−lowerInc = unsafeFunction "lower_inc"
219−
220−lowerInf :: null ('PGrange ty) --> 'Null 'PGbool
221−lowerInf = unsafeFunction "lower_inf"
222−
223−upperInc :: null ('PGrange ty) --> 'Null 'PGbool
224−upperInc = unsafeFunction "upper_inc"
225−
226−upperInf :: null ('PGrange ty) --> 'Null 'PGbool
227−upperInf = unsafeFunction "upper_inf"
228−
229−rangeMerge :: '[null ('PGrange ty), null ('PGrange ty)] ---> null ('PGrange ty)
230−rangeMerge = unsafeFunctionN "range_merge"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Set.hsdeleted−139
@@ -1,139 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Set
3−Description: Set returning functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Set returning functions
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DataKinds
14− , FlexibleContexts
15− , OverloadedStrings
16− , PolyKinds
17− , RankNTypes
18− , ScopedTypeVariables
19− , TypeApplications
20− , TypeOperators
21−#-}
22−
23−module Squeal.PostgreSQL.Expression.Set
24− ( generateSeries
25− , generateSeriesStep
26− , generateSeriesTimestamp
27− , SetFunction
28− , unsafeSetFunction
29− , SetFunctionDB
30− , setFunction
31− , SetFunctionN
32− , unsafeSetFunctionN
33− , SetFunctionNDB
34− , setFunctionN
35− ) where
36−
37−import GHC.TypeLits
38−
39−import qualified Generics.SOP as SOP
40−
41−import Squeal.PostgreSQL.Alias
42−import Squeal.PostgreSQL.Expression
43−import Squeal.PostgreSQL.List
44−import Squeal.PostgreSQL.Render
45−import Squeal.PostgreSQL.Query
46−import Squeal.PostgreSQL.Schema
47−
48−{- |
49−A @RankNType@ for set returning functions with 1 argument.
50−-}
51−type SetFunction fun ty row
52− = forall outer commons schemas params
53− . Expression outer commons 'Ungrouped schemas params '[] ty
54− -- ^ input
55− -> FromClause outer commons schemas params '[fun ::: row]
56− -- ^ output
57−
58−type SetFunctionDB fun schemas ty row
59− = forall outer commons params
60− . Expression outer commons 'Ungrouped schemas params '[] ty
61− -- ^ input
62− -> FromClause outer commons schemas params '[fun ::: row]
63− -- ^ output
64−
65−-- | Escape hatch for a set returning function with 1 argument.
66−unsafeSetFunction
67− :: forall fun ty row. KnownSymbol fun
68− => SetFunction fun ty row -- ^ set returning function
69−unsafeSetFunction x = UnsafeFromClause $
70− renderSymbol @fun <> parenthesized (renderSQL x)
71−
72−setFunction
73− :: ( Has sch schemas schema
74− , Has fun schema ('Function ('[ty] :=> 'ReturnsTable row)) )
75− => QualifiedAlias sch fun
76− -> SetFunctionDB fun schemas ty row
77−setFunction _ = unsafeSetFunction
78−
79−{- |
80−A @RankNType@ for set returning functions with multiple argument.
81−-}
82−type SetFunctionN fun tys row
83− = forall outer commons schemas params
84− . NP (Expression outer commons 'Ungrouped schemas params '[]) tys
85− -- ^ inputs
86− -> FromClause outer commons schemas params '[fun ::: row]
87− -- ^ output
88−
89−-- | Escape hatch for a set returning function with multiple argument.
90−unsafeSetFunctionN
91− :: forall fun tys row. (SOP.SListI tys, KnownSymbol fun)
92− => SetFunctionN fun tys row -- ^ set returning function
93−unsafeSetFunctionN xs = UnsafeFromClause $
94− renderSymbol @fun <> parenthesized (renderCommaSeparated renderSQL xs)
95−
96−type SetFunctionNDB fun schemas tys row
97− = forall outer commons params
98− . NP (Expression outer commons 'Ungrouped schemas params '[]) tys
99− -- ^ inputs
100− -> FromClause outer commons schemas params '[fun ::: row]
101− -- ^ output
102−
103−setFunctionN
104− :: ( Has sch schemas schema
105− , Has fun schema ('Function (tys :=> 'ReturnsTable row))
106− , SOP.SListI tys )
107− => QualifiedAlias sch fun
108− -> SetFunctionNDB fun schemas tys row
109−setFunctionN _ = unsafeSetFunctionN
110−
111−{- | @generateSeries (start *: stop)@
112−
113−Generate a series of values, from @start@ to @stop@ with a step size of one
114−-}
115−generateSeries
116− :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]
117− => SetFunctionN "generate_series" '[ null ty, null ty]
118− '["generate_series" ::: null ty] -- ^ set returning function
119−generateSeries = unsafeSetFunctionN
120−
121−{- | @generateSeries (start :* stop *: step)@
122−
123−Generate a series of values, from @start@ to @stop@ with a step size of @step@
124−-}
125−generateSeriesStep
126− :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]
127− => SetFunctionN "generate_series" '[null ty, null ty, null ty]
128− '["generate_series" ::: null ty] -- ^ set returning function
129−generateSeriesStep = unsafeSetFunctionN
130−
131−{- | @generateSeries (start :* stop *: step)@
132−
133−Generate a series of values, from @start@ to @stop@ with a step size of @step@
134−-}
135−generateSeriesTimestamp
136− :: ty `In` '[ 'PGtimestamp, 'PGtimestamptz]
137− => SetFunctionN "generate_series" '[null ty, null ty, null 'PGinterval]
138− '["generate_series" ::: null ty] -- ^ set returning function
139−generateSeriesTimestamp = unsafeSetFunctionN
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Sort.hsdeleted−85
@@ -1,85 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Sort
3−Description: Sort expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Sort expressions
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , GADTs
14− , LambdaCase
15− , OverloadedStrings
16− , StandaloneDeriving
17−#-}
18−
19−module Squeal.PostgreSQL.Expression.Sort
20− ( SortExpression (..)
21− , OrderBy (..)
22− ) where
23−
24−import Squeal.PostgreSQL.Expression
25−import Squeal.PostgreSQL.Render
26−import Squeal.PostgreSQL.Schema
27−
28−-- | `SortExpression`s are used by `orderBy` to optionally sort the results
29−-- of a `Squeal.PostgreSQL.Query.Query`. `Asc` or `Desc`
30−-- set the sort direction of a `NotNull` result
31−-- column to ascending or descending. Ascending order puts smaller values
32−-- first, where "smaller" is defined in terms of the
33−-- `Squeal.PostgreSQL.Expression.Comparison..<` operator. Similarly,
34−-- descending order is determined with the
35−-- `Squeal.PostgreSQL.Expression.Comparison..>` operator. `AscNullsFirst`,
36−-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to
37−-- determine whether nulls appear before or after non-null values in the sort
38−-- ordering of a `Null` result column.
39−data SortExpression outer commons grp schemas params from where
40− Asc
41− :: Expression outer commons grp schemas params from ('NotNull ty)
42− -> SortExpression outer commons grp schemas params from
43− Desc
44− :: Expression outer commons grp schemas params from ('NotNull ty)
45− -> SortExpression outer commons grp schemas params from
46− AscNullsFirst
47− :: Expression outer commons grp schemas params from ('Null ty)
48− -> SortExpression outer commons grp schemas params from
49− AscNullsLast
50− :: Expression outer commons grp schemas params from ('Null ty)
51− -> SortExpression outer commons grp schemas params from
52− DescNullsFirst
53− :: Expression outer commons grp schemas params from ('Null ty)
54− -> SortExpression outer commons grp schemas params from
55− DescNullsLast
56− :: Expression outer commons grp schemas params from ('Null ty)
57− -> SortExpression outer commons grp schemas params from
58−deriving instance Show (SortExpression outer commons grp schemas params from)
59−instance RenderSQL (SortExpression outer commons grp schemas params from) where
60− renderSQL = \case
61− Asc expression -> renderSQL expression <+> "ASC"
62− Desc expression -> renderSQL expression <+> "DESC"
63− AscNullsFirst expression -> renderSQL expression
64− <+> "ASC NULLS FIRST"
65− DescNullsFirst expression -> renderSQL expression
66− <+> "DESC NULLS FIRST"
67− AscNullsLast expression -> renderSQL expression <+> "ASC NULLS LAST"
68− DescNullsLast expression -> renderSQL expression <+> "DESC NULLS LAST"
69−
70−{- |
71−The `orderBy` clause causes the result rows of a `Squeal.PostgreSQL.Query.TableExpression`
72−to be sorted according to the specified `SortExpression`(s).
73−If two rows are equal according to the leftmost expression,
74−they are compared according to the next expression and so on.
75−If they are equal according to all specified expressions,
76−they are returned in an implementation-dependent order.
77−
78−You can also control the order in which rows are processed by window functions
79−using `orderBy` within `Squeal.PostgreSQL.Query.Over`.
80−-}
81−class OrderBy expr where
82− orderBy
83− :: [SortExpression outer commons grp schemas params from]
84− -> expr outer commons grp schemas params from
85− -> expr outer commons grp schemas params from
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Subquery.hsdeleted−120
@@ -1,120 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Subquery
3−Description: Subquery expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Subquery expressions
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , RankNTypes
15− , TypeOperators
16−#-}
17−
18−module Squeal.PostgreSQL.Expression.Subquery
19− ( exists
20− , in_
21− , notIn
22− , subAll
23− , subAny
24− ) where
25−
26−import Squeal.PostgreSQL.Alias
27−import Squeal.PostgreSQL.Expression
28−import Squeal.PostgreSQL.Expression.Logic
29−import Squeal.PostgreSQL.List
30−import Squeal.PostgreSQL.Query
31−import Squeal.PostgreSQL.Render
32−import Squeal.PostgreSQL.Schema
33−
34−-- $setup
35−-- >>> import Squeal.PostgreSQL
36−
37−{- |
38−The argument of `exists` is an arbitrary subquery. The subquery is evaluated
39−to determine whether it returns any rows. If it returns at least one row,
40−the result of `exists` is `true`; if the subquery returns no rows,
41−the result of `exists` is `false`.
42−
43−The subquery can refer to variables from the surrounding query,
44−which will act as constants during any one evaluation of the subquery.
45−
46−The subquery will generally only be executed long enough to determine whether
47−at least one row is returned, not all the way to completion.
48−-}
49−exists
50− :: Query (Join outer from) commons schemas params row
51− -> Condition outer commons grp schemas params from
52−exists query = UnsafeExpression $ "EXISTS" <+> parenthesized (renderSQL query)
53−
54−{- |
55−The right-hand side is a parenthesized subquery, which must return
56−exactly one column. The left-hand expression is evaluated and compared to each
57−row of the subquery result using the given `Operator`,
58−which must yield a Boolean result. The result of `subAll` is `true`
59−if all rows yield true (including the case where the subquery returns no rows).
60−The result is `false` if any `false` result is found.
61−The result is `Squeal.PostgreSQL.Expression.Null.null_` if
62− no comparison with a subquery row returns `false`,
63−and at least one comparison returns `Squeal.PostgreSQL.Expression.Null.null_`.
64−
65−>>> printSQL $ subAll true (.==) (values_ (true `as` #foo))
66−(TRUE = ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo")))
67−-}
68−subAll
69− :: Expression outer commons grp schemas params from ty1 -- ^ expression
70− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator
71− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery
72− -> Condition outer commons grp schemas params from
73−subAll expr (?) qry = expr ?
74− (UnsafeExpression $ "ALL" <+> parenthesized (renderSQL qry))
75−
76−{- |
77−The right-hand side is a parenthesized subquery, which must return exactly one column.
78−The left-hand expression is evaluated and compared to each row of the subquery result
79−using the given `Operator`, which must yield a Boolean result. The result of `subAny` is `true`
80−if any `true` result is obtained. The result is `false` if no true result is found
81−(including the case where the subquery returns no rows).
82−
83−>>> printSQL $ subAny "foo" like (values_ ("foobar" `as` #foo))
84−(E'foo' LIKE ANY (SELECT * FROM (VALUES (E'foobar')) AS t ("foo")))
85−-}
86−subAny
87− :: Expression outer commons grp schemas params from ty1 -- ^ expression
88− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator
89− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery
90− -> Condition outer commons grp schemas params from
91−subAny expr (?) qry = expr ?
92− (UnsafeExpression $ "ANY" <+> parenthesized (renderSQL qry))
93−
94−{- |
95−The result is `true` if the left-hand expression's result is equal
96−to any of the right-hand expressions.
97−
98−>>> printSQL $ true `in_` [true, false, null_]
99−TRUE IN (TRUE, FALSE, NULL)
100−-}
101−in_
102− :: Expression outer commons grp schemas params from ty -- ^ expression
103− -> [Expression outer commons grp schemas params from ty]
104− -> Condition outer commons grp schemas params from
105−expr `in_` exprs = UnsafeExpression $ renderSQL expr <+> "IN"
106− <+> parenthesized (commaSeparated (renderSQL <$> exprs))
107−
108−{- |
109−The result is `true` if the left-hand expression's result is not equal
110−to any of the right-hand expressions.
111−
112−>>> printSQL $ true `notIn` [false, null_]
113−TRUE NOT IN (FALSE, NULL)
114−-}
115−notIn
116− :: Expression outer commons grp schemas params from ty -- ^ expression
117− -> [Expression outer commons grp schemas params from ty]
118− -> Condition outer commons grp schemas params from
119−expr `notIn` exprs = UnsafeExpression $ renderSQL expr <+> "NOT IN"
120− <+> parenthesized (commaSeparated (renderSQL <$> exprs))
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Text.hsdeleted−64
@@ -1,64 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Text
3−Description: Text expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−String functions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , TypeOperators
15−#-}
16−
17−module Squeal.PostgreSQL.Expression.Text
18− ( lower
19− , upper
20− , charLength
21− , like
22− , ilike
23− ) where
24−
25−import Squeal.PostgreSQL.Expression
26−import Squeal.PostgreSQL.Schema
27−
28−-- $setup
29−-- >>> import Squeal.PostgreSQL
30−
31−-- | >>> printSQL $ lower "ARRRGGG"
32−-- lower(E'ARRRGGG')
33−lower :: null 'PGtext --> null 'PGtext
34−lower = unsafeFunction "lower"
35−
36−-- | >>> printSQL $ upper "eeee"
37−-- upper(E'eeee')
38−upper :: null 'PGtext --> null 'PGtext
39−upper = unsafeFunction "upper"
40−
41−-- | >>> printSQL $ charLength "four"
42−-- char_length(E'four')
43−charLength :: null 'PGtext --> null 'PGint4
44−charLength = unsafeFunction "char_length"
45−
46−-- | The `like` expression returns true if the @string@ matches
47−-- the supplied @pattern@. If @pattern@ does not contain percent signs
48−-- or underscores, then the pattern only represents the string itself;
49−-- in that case `like` acts like the equals operator. An underscore (_)
50−-- in pattern stands for (matches) any single character; a percent sign (%)
51−-- matches any sequence of zero or more characters.
52−--
53−-- >>> printSQL $ "abc" `like` "a%"
54−-- (E'abc' LIKE E'a%')
55−like :: Operator (null 'PGtext) (null 'PGtext) ('Null 'PGbool)
56−like = unsafeBinaryOp "LIKE"
57−
58−-- | The key word ILIKE can be used instead of LIKE to make the
59−-- match case-insensitive according to the active locale.
60−--
61−-- >>> printSQL $ "abc" `ilike` "a%"
62−-- (E'abc' ILIKE E'a%')
63−ilike :: Operator (null 'PGtext) (null 'PGtext) ('Null 'PGbool)
64−ilike = unsafeBinaryOp "ILIKE"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/TextSearch.hsdeleted−157
@@ -1,157 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.TextSearch
3−Description: Text search expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Text search functions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , OverloadedStrings
14− , TypeOperators
15−#-}
16−
17−module Squeal.PostgreSQL.Expression.TextSearch
18− ( (@@)
19− , (.&)
20− , (.|)
21− , (.!)
22− , (<->)
23− , arrayToTSvector
24− , tsvectorLength
25− , numnode
26− , plainToTSquery
27− , phraseToTSquery
28− , websearchToTSquery
29− , queryTree
30− , toTSquery
31− , toTSvector
32− , setWeight
33− , strip
34− , jsonToTSvector
35− , jsonbToTSvector
36− , tsDelete
37− , tsFilter
38− , tsHeadline
39− ) where
40−
41−import Squeal.PostgreSQL.Expression
42−import Squeal.PostgreSQL.List
43−import Squeal.PostgreSQL.Schema
44−
45−-- | `Squeal.PostgreSQL.Expression.Type.tsvector` matches tsquery ?
46−(@@) :: Operator (null 'PGtsvector) (null 'PGtsquery) ('Null 'PGbool)
47−(@@) = unsafeBinaryOp "@@"
48−
49−-- | AND `Squeal.PostgreSQL.Expression.Type.tsquery`s together
50−(.&) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)
51−(.&) = unsafeBinaryOp "&&"
52−
53−-- | OR `Squeal.PostgreSQL.Expression.Type.tsquery`s together
54−(.|) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)
55−(.|) = unsafeBinaryOp "||"
56−
57−-- | negate a `Squeal.PostgreSQL.Expression.Type.tsquery`
58−(.!) :: null 'PGtsquery --> null 'PGtsquery
59−(.!) = unsafeLeftOp "!!"
60−
61−-- | `Squeal.PostgreSQL.Expression.Type.tsquery` followed by
62−-- `Squeal.PostgreSQL.Expression.Type.tsquery`
63−(<->) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)
64−(<->) = unsafeBinaryOp "<->"
65−
66−-- | convert array of lexemes to `Squeal.PostgreSQL.Expression.Type.tsvector`
67−arrayToTSvector
68− :: null ('PGvararray ('NotNull 'PGtext))
69− --> null 'PGtsvector
70−arrayToTSvector = unsafeFunction "array_to_tsvector"
71−
72−-- | number of lexemes in `Squeal.PostgreSQL.Expression.Type.tsvector`
73−tsvectorLength :: null 'PGtsvector --> null 'PGint4
74−tsvectorLength = unsafeFunction "length"
75−
76−-- | number of lexemes plus operators in `Squeal.PostgreSQL.Expression.Type.tsquery`
77−numnode :: null 'PGtsquery --> null 'PGint4
78−numnode = unsafeFunction "numnode"
79−
80−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` ignoring punctuation
81−plainToTSquery :: null 'PGtext --> null 'PGtsquery
82−plainToTSquery = unsafeFunction "plainto_tsquery"
83−
84−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` that searches for a phrase,
85−-- ignoring punctuation
86−phraseToTSquery :: null 'PGtext --> null 'PGtsquery
87−phraseToTSquery = unsafeFunction "phraseto_tsquery"
88−
89−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` from a web search style query
90−websearchToTSquery :: null 'PGtext --> null 'PGtsquery
91−websearchToTSquery = unsafeFunction "websearch_to_tsquery"
92−
93−-- | get indexable part of a `Squeal.PostgreSQL.Expression.Type.tsquery`
94−queryTree :: null 'PGtsquery --> null 'PGtext
95−queryTree = unsafeFunction "query_tree"
96−
97−-- | normalize words and convert to `Squeal.PostgreSQL.Expression.Type.tsquery`
98−toTSquery :: null 'PGtext --> null 'PGtsquery
99−toTSquery = unsafeFunction "to_tsquery"
100−
101−-- | reduce document text to `Squeal.PostgreSQL.Expression.Type.tsvector`
102−toTSvector
103− :: ty `In` '[ 'PGtext, 'PGjson, 'PGjsonb]
104− => null ty --> null 'PGtsvector
105−toTSvector = unsafeFunction "to_tsvector"
106−
107−-- | assign weight to each element of `Squeal.PostgreSQL.Expression.Type.tsvector`
108−setWeight :: '[null 'PGtsvector, null ('PGchar 1)] ---> null 'PGtsvector
109−setWeight = unsafeFunctionN "set_weight"
110−
111−-- | remove positions and weights from `Squeal.PostgreSQL.Expression.Type.tsvector`
112−strip :: null 'PGtsvector --> null 'PGtsvector
113−strip = unsafeFunction "strip"
114−
115−-- | @jsonToTSvector (document *: filter)@
116−-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,
117−-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.
118−-- filter is a `Squeal.PostgreSQL.Expression.Type.json` array, that enumerates what kind of elements
119−-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.
120−-- Possible values for filter are "string" (to include all string values),
121−-- "numeric" (to include all numeric values in the string format),
122−-- "boolean" (to include all Boolean values in the string format "true"/"false"),
123−-- "key" (to include all keys) or "all" (to include all above).
124−-- These values can be combined together to include, e.g. all string and numeric values.
125−jsonToTSvector :: '[null 'PGjson, null 'PGjson] ---> null 'PGtsvector
126−jsonToTSvector = unsafeFunctionN "json_to_tsvector"
127−
128−-- | @jsonbToTSvector (document *: filter)@
129−-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,
130−-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.
131−-- filter is a `Squeal.PostgreSQL.Expression.Type.jsonb` array, that enumerates what kind of elements
132−-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.
133−-- Possible values for filter are "string" (to include all string values),
134−-- "numeric" (to include all numeric values in the string format),
135−-- "boolean" (to include all Boolean values in the string format "true"/"false"),
136−-- "key" (to include all keys) or "all" (to include all above).
137−-- These values can be combined together to include, e.g. all string and numeric values.
138−jsonbToTSvector :: '[null 'PGjsonb, null 'PGjsonb] ---> null 'PGtsvector
139−jsonbToTSvector = unsafeFunctionN "jsonb_to_tsvector"
140−
141−-- | remove given lexeme from `Squeal.PostgreSQL.Expression.Type.tsvector`
142−tsDelete ::
143− '[null 'PGtsvector, null ('PGvararray ('NotNull 'PGtext))]
144− ---> null 'PGtsvector
145−tsDelete = unsafeFunctionN "ts_delete"
146−
147−-- | select only elements with given weights from `Squeal.PostgreSQL.Expression.Type.tsvector`
148−tsFilter ::
149− '[null 'PGtsvector, null ('PGvararray ('NotNull ('PGchar 1)))]
150− ---> null 'PGtsvector
151−tsFilter = unsafeFunctionN "ts_filter"
152−
153−-- | display a `Squeal.PostgreSQL.Expression.Type.tsquery` match
154−tsHeadline
155− :: document `In` '[ 'PGtext, 'PGjson, 'PGjsonb]
156− => '[null document, null 'PGtsquery] ---> null 'PGtext
157−tsHeadline = unsafeFunctionN "ts_headline"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Time.hsdeleted−192
@@ -1,192 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Time
3−Description: Date/Time expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Date/Time functions and operators
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , DeriveGeneric
14− , FunctionalDependencies
15− , LambdaCase
16− , MultiParamTypeClasses
17− , OverloadedStrings
18− , PolyKinds
19− , RankNTypes
20− , TypeOperators
21−#-}
22−
23−module Squeal.PostgreSQL.Expression.Time
24− ( TimeOp (..)
25− , currentDate
26− , currentTime
27− , currentTimestamp
28− , localTime
29− , localTimestamp
30− , now
31− , makeDate
32− , makeTime
33− , makeTimestamp
34− , makeTimestamptz
35− , interval_
36− , TimeUnit (..)
37− ) where
38−
39−import Data.String
40−
41−import qualified GHC.Generics as GHC
42−import qualified Generics.SOP as SOP
43−
44−import Squeal.PostgreSQL.Expression
45−import Squeal.PostgreSQL.Render
46−import Squeal.PostgreSQL.Schema
47−
48−-- $setup
49−-- >>> import Squeal.PostgreSQL
50−
51−-- | >>> printSQL currentDate
52−-- CURRENT_DATE
53−currentDate :: Expr (null 'PGdate)
54−currentDate = UnsafeExpression "CURRENT_DATE"
55−
56−-- | >>> printSQL currentTime
57−-- CURRENT_TIME
58−currentTime :: Expr (null 'PGtimetz)
59−currentTime = UnsafeExpression "CURRENT_TIME"
60−
61−-- | >>> printSQL currentTimestamp
62−-- CURRENT_TIMESTAMP
63−currentTimestamp :: Expr (null 'PGtimestamptz)
64−currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"
65−
66−-- | >>> printSQL localTime
67−-- LOCALTIME
68−localTime :: Expr (null 'PGtime)
69−localTime = UnsafeExpression "LOCALTIME"
70−
71−-- | >>> printSQL localTimestamp
72−-- LOCALTIMESTAMP
73−localTimestamp :: Expr (null 'PGtimestamp)
74−localTimestamp = UnsafeExpression "LOCALTIMESTAMP"
75−
76−-- | Current date and time (equivalent to `currentTimestamp`)
77−--
78−-- >>> printSQL now
79−-- now()
80−now :: Expr (null 'PGtimestamptz)
81−now = UnsafeExpression "now()"
82−
83−{-|
84−Create date from year, month and day fields
85−
86−>>> printSQL (makeDate (1984 :* 7 *: 3))
87−make_date(1984, 7, 3)
88−-}
89−makeDate :: '[ null 'PGint4, null 'PGint4, null 'PGint4 ] ---> null 'PGdate
90−makeDate = unsafeFunctionN "make_date"
91−
92−{-|
93−Create time from hour, minute and seconds fields
94−
95−>>> printSQL (makeTime (8 :* 15 *: 23.5))
96−make_time(8, 15, 23.5)
97−-}
98−makeTime :: '[ null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtime
99−makeTime = unsafeFunctionN "make_time"
100−
101−{-|
102−Create timestamp from year, month, day, hour, minute and seconds fields
103−
104−>>> printSQL (makeTimestamp (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))
105−make_timestamp(2013, 7, 15, 8, 15, 23.5)
106−-}
107−makeTimestamp ::
108− '[ null 'PGint4, null 'PGint4, null 'PGint4
109− , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamp
110−makeTimestamp = unsafeFunctionN "make_timestamp"
111−
112−{-|
113−Create timestamp with time zone from
114−year, month, day, hour, minute and seconds fields;
115−the current time zone is used
116−
117−>>> printSQL (makeTimestamptz (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))
118−make_timestamptz(2013, 7, 15, 8, 15, 23.5)
119−-}
120−makeTimestamptz ::
121− '[ null 'PGint4, null 'PGint4, null 'PGint4
122− , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamptz
123−makeTimestamptz = unsafeFunctionN "make_timestamptz"
124−
125−{-|
126−Affine space operations on time types.
127−-}
128−class TimeOp time diff | time -> diff where
129− {-|
130− >>> printSQL (makeDate (1984 :* 7 *: 3) !+ 365)
131− (make_date(1984, 7, 3) + 365)
132− -}
133− (!+) :: Operator (null time) (null diff) (null time)
134− (!+) = unsafeBinaryOp "+"
135− {-|
136− >>> printSQL (365 +! makeDate (1984 :* 7 *: 3))
137− (365 + make_date(1984, 7, 3))
138− -}
139− (+!) :: Operator (null diff) (null time) (null time)
140− (+!) = unsafeBinaryOp "+"
141− {-|
142− >>> printSQL (makeDate (1984 :* 7 *: 3) !- 365)
143− (make_date(1984, 7, 3) - 365)
144− -}
145− (!-) :: Operator (null time) (null diff) (null time)
146− (!-) = unsafeBinaryOp "-"
147− {-|
148− >>> printSQL (makeDate (1984 :* 7 *: 3) !-! currentDate)
149− (make_date(1984, 7, 3) - CURRENT_DATE)
150− -}
151− (!-!) :: Operator (null time) (null time) (null diff)
152− (!-!) = unsafeBinaryOp "-"
153−instance TimeOp 'PGtimestamp 'PGinterval
154−instance TimeOp 'PGtimestamptz 'PGinterval
155−instance TimeOp 'PGtime 'PGinterval
156−instance TimeOp 'PGtimetz 'PGinterval
157−instance TimeOp 'PGinterval 'PGinterval
158−instance TimeOp 'PGdate 'PGint4
159−infixl 6 !+
160−infixl 6 +!
161−infixl 6 !-
162−infixl 6 !-!
163−
164−-- | A `TimeUnit` to use in `interval_` construction.
165−data TimeUnit
166− = Years | Months | Weeks | Days
167− | Hours | Minutes | Seconds
168− | Microseconds | Milliseconds
169− | Decades | Centuries | Millennia
170− deriving (Eq, Ord, Show, Read, Enum, GHC.Generic)
171−instance SOP.Generic TimeUnit
172−instance SOP.HasDatatypeInfo TimeUnit
173−instance RenderSQL TimeUnit where
174− renderSQL = \case
175− Years -> "years"
176− Months -> "months"
177− Weeks -> "weeks"
178− Days -> "days"
179− Hours -> "hours"
180− Minutes -> "minutes"
181− Seconds -> "seconds"
182− Microseconds -> "microseconds"
183− Milliseconds -> "milliseconds"
184− Decades -> "decades"
185− Centuries -> "centuries"
186− Millennia -> "millennia"
187−
188−-- | >>> printSQL $ interval_ 7 Days
189−-- (INTERVAL '7.0 days')
190−interval_ :: Double -> TimeUnit -> Expr (null 'PGinterval)
191−interval_ num unit = UnsafeExpression . parenthesized $ "INTERVAL" <+>
192− "'" <> fromString (show num) <+> renderSQL unit <> "'"
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Type.hsdeleted−446
@@ -1,446 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression
3−Description: Type expressions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Type expressions.
9−-}
10−
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DataKinds
14− , DeriveGeneric
15− , FlexibleContexts
16− , FlexibleInstances
17− , GADTs
18− , GeneralizedNewtypeDeriving
19− , KindSignatures
20− , MultiParamTypeClasses
21− , OverloadedStrings
22− , RankNTypes
23− , ScopedTypeVariables
24− , TypeApplications
25− , TypeOperators
26− , UndecidableInstances
27−#-}
28−
29−module Squeal.PostgreSQL.Expression.Type
30− ( -- * type casting
31− cast
32− , astype
33− , inferredtype
34− -- * type expressions
35− , TypeExpression (..)
36− , typedef
37− , typetable
38− , typeview
39− , bool
40− , int2
41− , smallint
42− , int4
43− , int
44− , integer
45− , int8
46− , bigint
47− , numeric
48− , float4
49− , real
50− , float8
51− , doublePrecision
52− , money
53− , text
54− , char
55− , character
56− , varchar
57− , characterVarying
58− , bytea
59− , timestamp
60− , timestampWithTimeZone
61− , timestamptz
62− , date
63− , time
64− , timeWithTimeZone
65− , timetz
66− , interval
67− , uuid
68− , inet
69− , json
70− , jsonb
71− , vararray
72− , fixarray
73− , tsvector
74− , tsquery
75− , oid
76− , int4range
77− , int8range
78− , numrange
79− , tsrange
80− , tstzrange
81− , daterange
82− -- * column type definitions
83− , ColumnTypeExpression (..)
84− , nullable
85− , notNullable
86− , default_
87− , serial2
88− , smallserial
89− , serial4
90− , serial
91− , serial8
92− , bigserial
93− , hask
94− -- * type inference
95− , PGTyped (..)
96− , PGNullityTyped (..)
97− , FieldTyped (..)
98− ) where
99−
100−import Control.DeepSeq
101−import Data.ByteString
102−import Data.String
103−import GHC.TypeLits
104−
105−import qualified Data.ByteString as ByteString
106−import qualified GHC.Generics as GHC
107−import qualified Generics.SOP as SOP
108−
109−import Squeal.PostgreSQL.Alias
110−import Squeal.PostgreSQL.Expression
111−import Squeal.PostgreSQL.PG
112−import Squeal.PostgreSQL.Render
113−import Squeal.PostgreSQL.Schema
114−
115−-- $setup
116−-- >>> import Squeal.PostgreSQL
117−
118−-- When a `cast` is applied to an `Expression` of a known type, it
119−-- represents a run-time type conversion. The cast will succeed only if a
120−-- suitable type conversion operation has been defined.
121−--
122−-- | >>> printSQL $ true & cast int4
123−-- (TRUE :: int4)
124−cast
125− :: TypeExpression schemas ty1
126− -- ^ type to cast as
127− -> Expression outer commons grp schemas params from ty0
128− -- ^ value to convert
129− -> Expression outer commons grp schemas params from ty1
130−cast ty x = UnsafeExpression $ parenthesized $
131− renderSQL x <+> "::" <+> renderSQL ty
132−
133−-- | A safe version of `cast` which just matches a value with its type.
134−--
135−-- >>> printSQL (1 & astype int)
136−-- (1 :: int)
137−astype
138− :: TypeExpression schemas ty
139− -- ^ type to specify as
140− -> Expression outer commons grp schemas params from ty
141− -- ^ value
142− -> Expression outer commons grp schemas params from ty
143−astype = cast
144−
145−-- | `inferredtype` will add a type annotation to an `Expression`
146−-- which can be useful for fixing the storage type of a value.
147−--
148−-- >>> printSQL (inferredtype true)
149−-- (TRUE :: bool)
150−inferredtype
151− :: PGTyped schemas ty
152− => Expression outer common grp schemas params from ty
153− -- ^ value
154− -> Expression outer common grp schemas params from ty
155−inferredtype = astype pgtype
156−
157−{-----------------------------------------
158−type expressions
159−-----------------------------------------}
160−
161−-- | `TypeExpression`s are used in `cast`s and
162−-- `Squeal.PostgreSQL.Definition.createTable` commands.
163−newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)
164− = UnsafeTypeExpression { renderTypeExpression :: ByteString }
165− deriving (GHC.Generic,Show,Eq,Ord,NFData)
166−instance RenderSQL (TypeExpression schemas ty) where
167− renderSQL = renderTypeExpression
168−
169−-- | The enum or composite type in a `Typedef` can be expressed by its alias.
170−typedef
171− :: (Has sch schemas schema, Has td schema ('Typedef ty))
172− => QualifiedAlias sch td
173− -- ^ type alias
174− -> TypeExpression schemas (null ty)
175−typedef = UnsafeTypeExpression . renderSQL
176−
177−-- | The composite type corresponding to a `Table` definition can be expressed
178−-- by its alias.
179−typetable
180− :: (Has sch schemas schema, Has tab schema ('Table table))
181− => QualifiedAlias sch tab
182− -- ^ table alias
183− -> TypeExpression schemas (null ('PGcomposite (TableToRow table)))
184−typetable = UnsafeTypeExpression . renderSQL
185−
186−-- | The composite type corresponding to a `View` definition can be expressed
187−-- by its alias.
188−typeview
189− :: (Has sch schemas schema, Has vw schema ('View view))
190− => QualifiedAlias sch vw
191− -- ^ view alias
192− -> TypeExpression schemas (null ('PGcomposite view))
193−typeview = UnsafeTypeExpression . renderSQL
194−
195−-- | logical Boolean (true/false)
196−bool :: TypeExpression schemas (null 'PGbool)
197−bool = UnsafeTypeExpression "bool"
198−-- | signed two-byte integer
199−int2, smallint :: TypeExpression schemas (null 'PGint2)
200−int2 = UnsafeTypeExpression "int2"
201−smallint = UnsafeTypeExpression "smallint"
202−-- | signed four-byte integer
203−int4, int, integer :: TypeExpression schemas (null 'PGint4)
204−int4 = UnsafeTypeExpression "int4"
205−int = UnsafeTypeExpression "int"
206−integer = UnsafeTypeExpression "integer"
207−-- | signed eight-byte integer
208−int8, bigint :: TypeExpression schemas (null 'PGint8)
209−int8 = UnsafeTypeExpression "int8"
210−bigint = UnsafeTypeExpression "bigint"
211−-- | arbitrary precision numeric type
212−numeric :: TypeExpression schemas (null 'PGnumeric)
213−numeric = UnsafeTypeExpression "numeric"
214−-- | single precision floating-point number (4 bytes)
215−float4, real :: TypeExpression schemas (null 'PGfloat4)
216−float4 = UnsafeTypeExpression "float4"
217−real = UnsafeTypeExpression "real"
218−-- | double precision floating-point number (8 bytes)
219−float8, doublePrecision :: TypeExpression schemas (null 'PGfloat8)
220−float8 = UnsafeTypeExpression "float8"
221−doublePrecision = UnsafeTypeExpression "double precision"
222−-- | currency amount
223−money :: TypeExpression schema (null 'PGmoney)
224−money = UnsafeTypeExpression "money"
225−-- | variable-length character string
226−text :: TypeExpression schemas (null 'PGtext)
227−text = UnsafeTypeExpression "text"
228−-- | fixed-length character string
229−char, character
230− :: forall n schemas null. (KnownNat n, 1 <= n)
231− => TypeExpression schemas (null ('PGchar n))
232−char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"
233−character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"
234−-- | variable-length character string
235−varchar, characterVarying
236− :: forall n schemas null. (KnownNat n, 1 <= n)
237− => TypeExpression schemas (null ('PGvarchar n))
238−varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"
239−characterVarying = UnsafeTypeExpression $
240− "character varying(" <> renderNat @n <> ")"
241−-- | binary data ("byte array")
242−bytea :: TypeExpression schemas (null 'PGbytea)
243−bytea = UnsafeTypeExpression "bytea"
244−-- | date and time (no time zone)
245−timestamp :: TypeExpression schemas (null 'PGtimestamp)
246−timestamp = UnsafeTypeExpression "timestamp"
247−-- | date and time, including time zone
248−timestampWithTimeZone, timestamptz :: TypeExpression schemas (null 'PGtimestamptz)
249−timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"
250−timestamptz = UnsafeTypeExpression "timestamptz"
251−-- | calendar date (year, month, day)
252−date :: TypeExpression schemas (null 'PGdate)
253−date = UnsafeTypeExpression "date"
254−-- | time of day (no time zone)
255−time :: TypeExpression schemas (null 'PGtime)
256−time = UnsafeTypeExpression "time"
257−-- | time of day, including time zone
258−timeWithTimeZone, timetz :: TypeExpression schemas (null 'PGtimetz)
259−timeWithTimeZone = UnsafeTypeExpression "time with time zone"
260−timetz = UnsafeTypeExpression "timetz"
261−-- | time span
262−interval :: TypeExpression schemas (null 'PGinterval)
263−interval = UnsafeTypeExpression "interval"
264−-- | universally unique identifier
265−uuid :: TypeExpression schemas (null 'PGuuid)
266−uuid = UnsafeTypeExpression "uuid"
267−-- | IPv4 or IPv6 host address
268−inet :: TypeExpression schemas (null 'PGinet)
269−inet = UnsafeTypeExpression "inet"
270−-- | textual JSON data
271−json :: TypeExpression schemas (null 'PGjson)
272−json = UnsafeTypeExpression "json"
273−-- | binary JSON data, decomposed
274−jsonb :: TypeExpression schemas (null 'PGjsonb)
275−jsonb = UnsafeTypeExpression "jsonb"
276−-- | variable length array
277−vararray
278− :: TypeExpression schemas pg
279− -> TypeExpression schemas (null ('PGvararray pg))
280−vararray ty = UnsafeTypeExpression $ renderSQL ty <> "[]"
281−-- | fixed length array
282−--
283−-- >>> renderSQL (fixarray @'[2] json)
284−-- "json[2]"
285−fixarray
286− :: forall dims schemas null pg. SOP.All KnownNat dims
287− => TypeExpression schemas pg
288− -> TypeExpression schemas (null ('PGfixarray dims pg))
289−fixarray ty = UnsafeTypeExpression $
290− renderSQL ty <> renderDims @dims
291− where
292− renderDims :: forall ns. SOP.All KnownNat ns => ByteString
293− renderDims =
294− ("[" <>)
295− . (<> "]")
296− . ByteString.intercalate "]["
297− . SOP.hcollapse
298− $ SOP.hcmap (SOP.Proxy @KnownNat)
299− (K . fromString . show . natVal)
300− (SOP.hpure SOP.Proxy :: SOP.NP SOP.Proxy ns)
301−-- | text search query
302−tsvector :: TypeExpression schemas (null 'PGtsvector)
303−tsvector = UnsafeTypeExpression "tsvector"
304−-- | text search document
305−tsquery :: TypeExpression schemas (null 'PGtsquery)
306−tsquery = UnsafeTypeExpression "tsquery"
307−-- | Object identifiers (OIDs) are used internally by PostgreSQL
308−-- as primary keys for various system tables.
309−oid :: TypeExpression schemas (null 'PGoid)
310−oid = UnsafeTypeExpression "oid"
311−-- | Range of integer
312−int4range :: TypeExpression schemas (null ('PGrange 'PGint4))
313−int4range = UnsafeTypeExpression "int4range"
314−-- | Range of bigint
315−int8range :: TypeExpression schemas (null ('PGrange 'PGint8))
316−int8range = UnsafeTypeExpression "int8range"
317−-- | Range of numeric
318−numrange :: TypeExpression schemas (null ('PGrange 'PGnumeric))
319−numrange = UnsafeTypeExpression "numrange"
320−-- | Range of timestamp without time zone
321−tsrange :: TypeExpression schemas (null ('PGrange 'PGtimestamp))
322−tsrange = UnsafeTypeExpression "tsrange"
323−-- | Range of timestamp with time zone
324−tstzrange :: TypeExpression schemas (null ('PGrange 'PGtimestamptz))
325−tstzrange = UnsafeTypeExpression "tstzrange"
326−-- | Range of date
327−daterange :: TypeExpression schemas (null ('PGrange 'PGdate))
328−daterange = UnsafeTypeExpression "daterange"
329−
330−-- | `pgtype` is a demoted version of a `PGType`
331−class PGTyped schemas (ty :: NullityType) where
332− pgtype :: TypeExpression schemas ty
333−instance PGTyped schemas (null 'PGbool) where pgtype = bool
334−instance PGTyped schemas (null 'PGint2) where pgtype = int2
335−instance PGTyped schemas (null 'PGint4) where pgtype = int4
336−instance PGTyped schemas (null 'PGint8) where pgtype = int8
337−instance PGTyped schemas (null 'PGnumeric) where pgtype = numeric
338−instance PGTyped schemas (null 'PGfloat4) where pgtype = float4
339−instance PGTyped schemas (null 'PGfloat8) where pgtype = float8
340−instance PGTyped schemas (null 'PGmoney) where pgtype = money
341−instance PGTyped schemas (null 'PGtext) where pgtype = text
342−instance (KnownNat n, 1 <= n)
343− => PGTyped schemas (null ('PGchar n)) where pgtype = char @n
344−instance (KnownNat n, 1 <= n)
345− => PGTyped schemas (null ('PGvarchar n)) where pgtype = varchar @n
346−instance PGTyped schemas (null 'PGbytea) where pgtype = bytea
347−instance PGTyped schemas (null 'PGtimestamp) where pgtype = timestamp
348−instance PGTyped schemas (null 'PGtimestamptz) where pgtype = timestampWithTimeZone
349−instance PGTyped schemas (null 'PGdate) where pgtype = date
350−instance PGTyped schemas (null 'PGtime) where pgtype = time
351−instance PGTyped schemas (null 'PGtimetz) where pgtype = timeWithTimeZone
352−instance PGTyped schemas (null 'PGinterval) where pgtype = interval
353−instance PGTyped schemas (null 'PGuuid) where pgtype = uuid
354−instance PGTyped schemas (null 'PGjson) where pgtype = json
355−instance PGTyped schemas (null 'PGjsonb) where pgtype = jsonb
356−instance PGTyped schemas ty
357− => PGTyped schemas (null ('PGvararray ty)) where
358− pgtype = vararray (pgtype @schemas @ty)
359−instance (SOP.All KnownNat dims, PGTyped schemas ty)
360− => PGTyped schemas (null ('PGfixarray dims ty)) where
361− pgtype = fixarray @dims (pgtype @schemas @ty)
362−instance PGTyped schemas (null 'PGtsvector) where pgtype = tsvector
363−instance PGTyped schemas (null 'PGtsquery) where pgtype = tsquery
364−instance PGTyped schemas (null 'PGoid) where pgtype = oid
365−instance PGTyped schemas (null ('PGrange 'PGint4)) where pgtype = int4range
366−instance PGTyped schemas (null ('PGrange 'PGint8)) where pgtype = int8range
367−instance PGTyped schemas (null ('PGrange 'PGnumeric)) where pgtype = numrange
368−instance PGTyped schemas (null ('PGrange 'PGtimestamp)) where pgtype = tsrange
369−instance PGTyped schemas (null ('PGrange 'PGtimestamptz)) where pgtype = tstzrange
370−instance PGTyped schemas (null ('PGrange 'PGdate)) where pgtype = daterange
371−
372−-- | Lift `PGTyped` to a field
373−class FieldTyped schemas ty where
374− fieldtype :: Aliased (TypeExpression schemas) ty
375−instance (KnownSymbol alias, PGTyped schemas ty)
376− => FieldTyped schemas (alias ::: ty) where
377− fieldtype = pgtype `As` Alias
378−
379−-- | `ColumnTypeExpression`s are used in `createTable` commands.
380−newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)
381− = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }
382− deriving (GHC.Generic,Show,Eq,Ord,NFData)
383−instance RenderSQL (ColumnTypeExpression schemas ty) where
384− renderSQL = renderColumnTypeExpression
385−
386−-- | used in `createTable` commands as a column constraint to note that
387−-- @NULL@ may be present in a column
388−nullable
389− :: TypeExpression schemas (nullity ty)
390− -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)
391−nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"
392−
393−-- | used in `createTable` commands as a column constraint to ensure
394−-- @NULL@ is not present in a column
395−notNullable
396− :: TypeExpression schemas (nullity ty)
397− -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)
398−notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"
399−
400−-- | used in `createTable` commands as a column constraint to give a default
401−default_
402− :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty
403− -> ColumnTypeExpression schemas ('NoDef :=> ty)
404− -> ColumnTypeExpression schemas ('Def :=> ty)
405−default_ x ty = UnsafeColumnTypeExpression $
406− renderSQL ty <+> "DEFAULT" <+> renderExpression x
407−
408−-- | not a true type, but merely a notational convenience for creating
409−-- unique identifier columns with type `PGint2`
410−serial2, smallserial
411− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)
412−serial2 = UnsafeColumnTypeExpression "serial2"
413−smallserial = UnsafeColumnTypeExpression "smallserial"
414−-- | not a true type, but merely a notational convenience for creating
415−-- unique identifier columns with type `PGint4`
416−serial4, serial
417− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)
418−serial4 = UnsafeColumnTypeExpression "serial4"
419−serial = UnsafeColumnTypeExpression "serial"
420−-- | not a true type, but merely a notational convenience for creating
421−-- unique identifier columns with type `PGint8`
422−serial8, bigserial
423− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)
424−serial8 = UnsafeColumnTypeExpression "serial8"
425−bigserial = UnsafeColumnTypeExpression "bigserial"
426−
427−-- | Like @PGTyped@ but also accounts for nullity.
428−class PGNullityTyped schemas (nullty :: NullityType) where
429− pgNullityType :: ColumnTypeExpression schemas ('NoDef :=> nullty)
430−
431−instance PGTyped schemas ('Null ty) => PGNullityTyped schemas ('Null ty) where
432− pgNullityType = nullable (pgtype @_ @('Null ty))
433−
434−instance PGTyped schemas ('NotNull ty) => PGNullityTyped schemas ('NotNull ty) where
435− pgNullityType = notNullable (pgtype @_ @('NotNull ty))
436−
437−-- | Allow you to specify pg column types in relation to haskell types.
438−-- >>> printSQL $ hask @(Maybe String)
439−-- text NULL
440−--
441−-- >>> printSQL $ hask @Double
442−-- float8 NOT NULL
443−hask
444− :: forall hask schemas. PGNullityTyped schemas (NullPG hask)
445− => ColumnTypeExpression schemas ('NoDef :=> NullPG hask)
446−hask = pgNullityType
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Window.hsdeleted−284
@@ -1,284 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.Expression.Window
3−Description: Window functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Window functions and definitions
9−-}
10−
11−{-# LANGUAGE
12− DataKinds
13− , DeriveGeneric
14− , FlexibleContexts
15− , FlexibleInstances
16− , GADTs
17− , GeneralizedNewtypeDeriving
18− , LambdaCase
19− , MultiParamTypeClasses
20− , OverloadedStrings
21− , RankNTypes
22− , KindSignatures
23−#-}
24−
25−module Squeal.PostgreSQL.Expression.Window
26− ( -- * functions
27− partitionBy
28− , rank
29− , rowNumber
30− , denseRank
31− , percentRank
32− , cumeDist
33− , ntile
34− , lag
35− , lead
36− , firstValue
37− , lastValue
38− , nthValue
39− , unsafeWindowFunction1
40− , unsafeWindowFunctionN
41− -- * types
42− , WindowFunction (..)
43− , WindowDefinition (..)
44− , WinFun0
45− , WinFun1
46− , WinFunN
47− ) where
48−
49−import Control.DeepSeq
50−import Data.ByteString
51−
52−import qualified GHC.Generics as GHC
53−import qualified Generics.SOP as SOP
54−
55−import Squeal.PostgreSQL.Alias
56−import Squeal.PostgreSQL.Expression
57−import Squeal.PostgreSQL.Expression.Aggregate
58−import Squeal.PostgreSQL.Expression.Sort
59−import Squeal.PostgreSQL.List
60−import Squeal.PostgreSQL.Render
61−import Squeal.PostgreSQL.Schema
62−
63−instance Aggregate
64− (Expression outer commons grp schemas params from)
65− (NP (Expression outer commons grp schemas params from))
66− (WindowFunction outer commons grp schemas params from) where
67− countStar = UnsafeWindowFunction "count(*)"
68− count = unsafeWindowFunction1 "count"
69− sum_ = unsafeWindowFunction1 "sum"
70− arrayAgg = unsafeWindowFunction1 "array_agg"
71− jsonAgg = unsafeWindowFunction1 "json_agg"
72− jsonbAgg = unsafeWindowFunction1 "jsonb_agg"
73− bitAnd = unsafeWindowFunction1 "bit_and"
74− bitOr = unsafeWindowFunction1 "bit_or"
75− boolAnd = unsafeWindowFunction1 "bool_and"
76− boolOr = unsafeWindowFunction1 "bool_or"
77− every = unsafeWindowFunction1 "every"
78− max_ = unsafeWindowFunction1 "max"
79− min_ = unsafeWindowFunction1 "min"
80− avg = unsafeWindowFunction1 "avg"
81− corr = unsafeWindowFunctionN "corr"
82− covarPop = unsafeWindowFunctionN "covar_pop"
83− covarSamp = unsafeWindowFunctionN "covar_samp"
84− regrAvgX = unsafeWindowFunctionN "regr_avgx"
85− regrAvgY = unsafeWindowFunctionN "regr_avgy"
86− regrCount = unsafeWindowFunctionN "regr_count"
87− regrIntercept = unsafeWindowFunctionN "regr_intercept"
88− regrR2 = unsafeWindowFunctionN "regr_r2"
89− regrSlope = unsafeWindowFunctionN "regr_slope"
90− regrSxx = unsafeWindowFunctionN "regr_sxx"
91− regrSxy = unsafeWindowFunctionN "regr_sxy"
92− regrSyy = unsafeWindowFunctionN "regr_syy"
93− stddev = unsafeWindowFunction1 "stddev"
94− stddevPop = unsafeWindowFunction1 "stddev_pop"
95− stddevSamp = unsafeWindowFunction1 "stddev_samp"
96− variance = unsafeWindowFunction1 "variance"
97− varPop = unsafeWindowFunction1 "var_pop"
98− varSamp = unsafeWindowFunction1 "var_samp"
99−
100−-- | A `WindowDefinition` is a set of table rows that are somehow related
101−-- to the current row
102−data WindowDefinition outer commons grp schemas params from where
103− WindowDefinition
104− :: SOP.SListI bys
105− => NP (Expression outer commons grp schemas params from) bys
106− -- ^ `partitionBy` clause
107− -> [SortExpression outer commons grp schemas params from]
108− -- ^ `Squeal.PostgreSQL.Expression.Sort.orderBy` clause
109− -> WindowDefinition outer commons grp schemas params from
110−
111−instance OrderBy WindowDefinition where
112− orderBy sortsR (WindowDefinition parts sortsL)
113− = WindowDefinition parts (sortsL ++ sortsR)
114−
115−instance RenderSQL (WindowDefinition outer commons schemas from grp params) where
116− renderSQL (WindowDefinition part ord) =
117− renderPartitionByClause part <> renderOrderByClause ord
118− where
119− renderPartitionByClause = \case
120− Nil -> ""
121− parts -> "PARTITION" <+> "BY" <+> renderCommaSeparated renderExpression parts
122− renderOrderByClause = \case
123− [] -> ""
124− srts -> " ORDER" <+> "BY"
125− <+> commaSeparated (renderSQL <$> srts)
126−
127−{- |
128−The `partitionBy` clause within `Squeal.PostgreSQL.Query.Over` divides the rows into groups,
129−or partitions, that share the same values of the `partitionBy` `Expression`(s).
130−For each row, the window function is computed across the rows that fall into
131−the same partition as the current row.
132−-}
133−partitionBy
134− :: SOP.SListI bys
135− => NP (Expression outer commons grp schemas params from) bys -- ^ partitions
136− -> WindowDefinition outer commons grp schemas params from
137−partitionBy bys = WindowDefinition bys []
138−
139−{- |
140−A window function performs a calculation across a set of table rows
141−that are somehow related to the current row. This is comparable to the type
142−of calculation that can be done with an aggregate function.
143−However, window functions do not cause rows to become grouped into a single
144−output row like non-window aggregate calls would.
145−Instead, the rows retain their separate identities.
146−Behind the scenes, the window function is able to access more than
147−just the current row of the query result.
148−-}
149−newtype WindowFunction
150− (outer :: FromType)
151− (commons :: FromType)
152− (grp :: Grouping)
153− (schemas :: SchemasType)
154− (params :: [NullityType])
155− (from :: FromType)
156− (ty :: NullityType)
157− = UnsafeWindowFunction { renderWindowFunction :: ByteString }
158− deriving (GHC.Generic,Show,Eq,Ord,NFData)
159−
160−instance RenderSQL (WindowFunction outer commons grp schemas params from ty) where
161− renderSQL = renderWindowFunction
162−
163−{- |
164−A @RankNType@ for window functions with no arguments.
165−-}
166−type WinFun0 x
167− = forall outer commons grp schemas params from
168− . WindowFunction outer commons grp schemas params from x
169− -- ^ cannot reference aliases
170−
171−{- |
172−A @RankNType@ for window functions with 1 argument.
173−-}
174−type WinFun1 x y
175− = forall outer commons grp schemas params from
176− . Expression outer commons grp schemas params from x
177− -- ^ input
178− -> WindowFunction outer commons grp schemas params from y
179− -- ^ output
180−
181−{- | A @RankNType@ for window functions with a fixed-length
182−list of heterogeneous arguments.
183−Use the `*:` operator to end your argument lists.
184−-}
185−type WinFunN xs y
186− = forall outer commons grp schemas params from
187− . NP (Expression outer commons grp schemas params from) xs
188− -- ^ inputs
189− -> WindowFunction outer commons grp schemas params from y
190− -- ^ output
191−
192−-- | escape hatch for defining window functions
193−unsafeWindowFunction1 :: ByteString -> WinFun1 x y
194−unsafeWindowFunction1 fun x
195− = UnsafeWindowFunction $ fun <> parenthesized (renderSQL x)
196−
197−-- | escape hatch for defining multi-argument window functions
198−unsafeWindowFunctionN :: SOP.SListI xs => ByteString -> WinFunN xs y
199−unsafeWindowFunctionN fun xs = UnsafeWindowFunction $ fun <>
200− parenthesized (renderCommaSeparated renderSQL xs)
201−
202−{- | rank of the current row with gaps; same as `rowNumber` of its first peer
203−
204−>>> printSQL rank
205−rank()
206−-}
207−rank :: WinFun0 ('NotNull 'PGint8)
208−rank = UnsafeWindowFunction "rank()"
209−
210−{- | number of the current row within its partition, counting from 1
211−
212−>>> printSQL rowNumber
213−row_number()
214−-}
215−rowNumber :: WinFun0 ('NotNull 'PGint8)
216−rowNumber = UnsafeWindowFunction "row_number()"
217−
218−{- | rank of the current row without gaps; this function counts peer groups
219−
220−>>> printSQL denseRank
221−dense_rank()
222−-}
223−denseRank :: WinFun0 ('NotNull 'PGint8)
224−denseRank = UnsafeWindowFunction "dense_rank()"
225−
226−{- | relative rank of the current row: (rank - 1) / (total partition rows - 1)
227−
228−>>> printSQL percentRank
229−percent_rank()
230−-}
231−percentRank :: WinFun0 ('NotNull 'PGfloat8)
232−percentRank = UnsafeWindowFunction "percent_rank()"
233−
234−{- | cumulative distribution: (number of partition rows
235−preceding or peer with current row) / total partition rows
236−
237−>>> printSQL cumeDist
238−cume_dist()
239−-}
240−cumeDist :: WinFun0 ('NotNull 'PGfloat8)
241−cumeDist = UnsafeWindowFunction "cume_dist()"
242−
243−{- | integer ranging from 1 to the argument value,
244−dividing the partition as equally as possible
245−
246−>>> printSQL $ ntile 5
247−ntile(5)
248−-}
249−ntile :: WinFun1 ('NotNull 'PGint4) ('NotNull 'PGint4)
250−ntile = unsafeWindowFunction1 "ntile"
251−
252−{- | returns value evaluated at the row that is offset rows before the current
253−row within the partition; if there is no such row, instead return default
254−(which must be of the same type as value). Both offset and default are
255−evaluated with respect to the current row.
256−-}
257−lag :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty
258−lag = unsafeWindowFunctionN "lag"
259−
260−{- | returns value evaluated at the row that is offset rows after the current
261−row within the partition; if there is no such row, instead return default
262−(which must be of the same type as value). Both offset and default are
263−evaluated with respect to the current row.
264−-}
265−lead :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty
266−lead = unsafeWindowFunctionN "lead"
267−
268−{- | returns value evaluated at the row that is the
269−first row of the window frame
270−-}
271−firstValue :: WinFun1 ty ty
272−firstValue = unsafeWindowFunction1 "first_value"
273−
274−{- | returns value evaluated at the row that is the
275−last row of the window frame
276−-}
277−lastValue :: WinFun1 ty ty
278−lastValue = unsafeWindowFunction1 "last_value"
279−
280−{- | returns value evaluated at the row that is the nth
281−row of the window frame (counting from 1); null if no such row
282−-}
283−nthValue :: WinFunN '[null ty, 'NotNull 'PGint4] ('Null ty)
284−nthValue = unsafeWindowFunctionN "nth_value"
squeal-postgresql/src/Squeal/PostgreSQL/List.hsdeleted−112
@@ -1,112 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.List
3−Description: List related types and functions
4−Copyright: (c) Eitan Chatav, 2019
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−Haskell singly-linked lists are very powerful. This module
9−provides functionality for type-level lists, heterogeneous
10−lists and type aligned lists.
11−-}
12−
13−{-# LANGUAGE
14− DataKinds
15− , FlexibleContexts
16− , GADTs
17− , LambdaCase
18− , MultiParamTypeClasses
19− , OverloadedStrings
20− , PolyKinds
21− , QuantifiedConstraints
22− , RankNTypes
23− , ScopedTypeVariables
24− , TypeApplications
25− , TypeFamilies
26− , TypeOperators
27− , UndecidableInstances
28−#-}
29−
30−module Squeal.PostgreSQL.List
31− ( SOP.NP (..)
32− , (*:)
33− , Join
34− , disjoin
35− , Additional (..)
36− , Path (..)
37− , CFunctor (..)
38− , CFoldable (..)
39− , CFree (..)
40− , Elem
41− , In
42− , Length
43− ) where
44−
45−import Control.Category.Free
46−import Data.Function ((&))
47−import Data.Kind
48−import Data.Type.Bool
49−import GHC.TypeLits
50−
51−import Generics.SOP as SOP
52−
53−-- | `Join` is simply promoted `++` and is used in @JOIN@s in
54−-- `Squeal.PostgreSQL.Query.FromClause`s.
55−type family Join xs ys where
56− Join '[] ys = ys
57− Join (x ': xs) ys = x ': Join xs ys
58−
59−-- | `disjoin` is a utility function for splitting an `NP` list into pieces.
60−disjoin
61− :: forall xs ys expr. SListI xs
62− => NP expr (Join xs ys)
63− -> (NP expr xs, NP expr ys)
64−disjoin = case sList @xs of
65− SNil -> \ys -> (Nil, ys)
66− SCons -> \(x :* xsys) ->
67− case disjoin xsys of (xs,ys) -> (x :* xs, ys)
68−
69−-- | The `Additional` class is for appending
70−-- type-level list parameterized constructors such as `NP`,
71−-- `Squeal.PostgreSQL.Query.Selection`, and `Squeal.PostgreSQL.Query.FromClause`.
72−class Additional expr where
73− also :: expr ys -> expr xs -> expr (Join xs ys)
74−instance Additional (NP expr) where
75− also ys = \case
76− Nil -> ys
77− x :* xs -> x :* (xs & also ys)
78−
79−-- | A useful operator for ending an `NP` list of length at least 2 without `Nil`.
80−(*:) :: f x -> f y -> NP f '[x,y]
81−x *: y = x :* y :* Nil
82−infixl 9 *:
83−
84−-- | @Elem@ is a promoted `Data.List.elem`.
85−type family Elem x xs where
86− Elem x '[] = 'False
87− Elem x (x ': _) = 'True
88− Elem x (_ ': x ': _) = 'True
89− Elem x (_ ': _ ': x ': _) = 'True
90− Elem x (_ ': _ ': _ ': x ': _) = 'True
91− Elem x (_ ': _ ': _ ': _ ': x ': _) = 'True
92− Elem x (_ ': _ ': _ ': _ ': _ ': x ': _) = 'True
93− Elem x (_ ': xs) = Elem x xs
94−
95−-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.
96−type family In x xs :: Constraint where
97− In x xs = If (Elem x xs) (() :: Constraint)
98− (TypeError ('ShowType x ':<>: 'Text " is not in " ':<>: 'ShowType xs))
99−
100−{- | Calculate the `Length` of a type level list
101−
102−>>> :kind! Length '[Char,String,Bool,Double]
103−Length '[Char,String,Bool,Double] :: Nat
104−= 4
105−-}
106−type family Length (xs :: [k]) :: Nat where
107− Length (_ ': _ ': _ ': _ ': _ : xs) = 5 + Length xs
108− Length (_ ': _ ': _ ': _ : xs) = 4 + Length xs
109− Length (_ ': _ ': _ : xs) = 3 + Length xs
110− Length (_ ': _ : xs) = 2 + Length xs
111− Length (_ : xs) = 1 + Length xs
112− Length '[] = 0
squeal-postgresql/src/Squeal/PostgreSQL/Manipulation.hs+340−411
@@ -11,139 +11,84 @@ Squeal data manipulation language.
11{-# LANGUAGE
11{-# LANGUAGE
12 DeriveGeneric
12 DeriveGeneric
13 , FlexibleContexts
13 , FlexibleContexts
14− , FlexibleInstances
15 , GADTs
14 , GADTs
16 , GeneralizedNewtypeDeriving
15 , GeneralizedNewtypeDeriving
17 , LambdaCase
16 , LambdaCase
18− , MultiParamTypeClasses
19 , OverloadedStrings
17 , OverloadedStrings
20− , PatternSynonyms
21− , QuantifiedConstraints
22 , RankNTypes
18 , RankNTypes
23− , ScopedTypeVariables
24− , TypeApplications
25− , TypeFamilies
26 , TypeInType
19 , TypeInType
27 , TypeOperators
20 , TypeOperators
28− , UndecidableInstances
29#-}
21#-}
30
22
31module Squeal.PostgreSQL.Manipulation
23module Squeal.PostgreSQL.Manipulation
32 ( -- * Manipulation
24 ( -- * Manipulation
33− Manipulation_
34− , Manipulation (..)
25+ Manipulation (UnsafeManipulation, renderManipulation)
35 , queryStatement
26 , queryStatement
27+ , ColumnValue (..)
28+ , ReturningClause (ReturningStar, Returning)
29+ , ConflictClause (OnConflictDoRaise, OnConflictDoNothing, OnConflictDoUpdate)
36 -- * Insert
30 -- * Insert
37− , insertInto
31+ , insertRows
38− , insertInto_
32+ , insertRow
33+ , insertRows_
34+ , insertRow_
35+ , insertQuery
36+ , insertQuery_
37+ , renderReturningClause
38+ , renderConflictClause
39 -- * Update
39 -- * Update
40 , update
40 , update
41 , update_
41 , update_
42 -- * Delete
42 -- * Delete
43 , deleteFrom
43 , deleteFrom
44 , deleteFrom_
44 , deleteFrom_
45− -- * Clauses
45+ -- * With
46− , Optional (..)
46+ , with
47− , QueryClause (..)
48− , pattern Values_
49− , ReturningClause (..)
50− , pattern Returning_
51− , ConflictClause (..)
52− , ConflictTarget (..)
53− , ConflictAction (..)
54− , UsingClause (..)
55 ) where
47 ) where
56
48
57import Control.DeepSeq
49import Control.DeepSeq
58import Data.ByteString hiding (foldr)
50import Data.ByteString hiding (foldr)
59−import Data.Kind (Type)
51+import Data.Monoid
60
52
61import qualified Generics.SOP as SOP
53import qualified Generics.SOP as SOP
62import qualified GHC.Generics as GHC
54import qualified GHC.Generics as GHC
63
55
64−import Squeal.PostgreSQL.Alias
65import Squeal.PostgreSQL.Expression
56import Squeal.PostgreSQL.Expression
66−import Squeal.PostgreSQL.Expression.Logic
67−import Squeal.PostgreSQL.List
68−import Squeal.PostgreSQL.PG
69import Squeal.PostgreSQL.Render
57import Squeal.PostgreSQL.Render
70import Squeal.PostgreSQL.Query
58import Squeal.PostgreSQL.Query
71import Squeal.PostgreSQL.Schema
59import Squeal.PostgreSQL.Schema
72
60
73−-- $setup
74−-- >>> import Squeal.PostgreSQL
75−-- >>> import Data.Int
76−-- >>> import Data.Time
77−
78{- |
61{- |
79A `Manipulation` is a statement which may modify data in the database,
62A `Manipulation` is a statement which may modify data in the database,
80−but does not alter its schemas. Examples are inserts, updates and deletes.
63+but does not alter the schema. Examples are inserts, updates and deletes.
81A `Query` is also considered a `Manipulation` even though it does not modify data.
64A `Query` is also considered a `Manipulation` even though it does not modify data.
82
65
83−The general `Manipulation` type is parameterized by
84−
85−* @commons :: FromType@ - scope for all `common` table expressions,
86−* @schemas :: SchemasType@ - scope for all `table`s and `view`s,
87−* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,
88−* @row :: RowType@ - return type of the `Query`.
89−-}
90−newtype Manipulation
91− (commons :: FromType)
92− (schemas :: SchemasType)
93− (params :: [NullityType])
94− (columns :: RowType)
95− = UnsafeManipulation { renderManipulation :: ByteString }
96− deriving (GHC.Generic,Show,Eq,Ord,NFData)
97−instance RenderSQL (Manipulation commons schemas params columns) where
98− renderSQL = renderManipulation
99−instance With Manipulation where
100− with Done manip = manip
101− with ctes manip = UnsafeManipulation $
102− "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL manip
103−
104−{- |
105−The top level `Manipulation_` type is parameterized by a @schemas@ `SchemasType`,
106−against which the query is type-checked, an input @parameters@ Haskell `Type`,
107−and an ouput row Haskell `Type`.
108−
109−A top-level `Manipulation_` can be run
110−using `Squeal.PostgreSQL.PQ.manipulateParams`, or if @parameters = ()@
111−using `Squeal.PostgreSQL.PQ.manipulate`.
112−
113−Generally, @parameters@ will be a Haskell tuple or record whose entries
114−may be referenced using positional
115−`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a
116−Haskell record, whose entries will be targeted using overloaded labels.
117−
118−>>> :set -XDeriveAnyClass -XDerivingStrategies
119−>>> :{
120−data Row a b = Row { col1 :: a, col2 :: b }
121− deriving stock (GHC.Generic)
122− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)
123−:}
124−
125simple insert:
66simple insert:
126
67
127−>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]
128−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
129>>> :{
68>>> :{
130let
69let
131− manipulation :: Manipulation_ (Public Schema) () ()
70+ manipulation :: Manipulation
71+ '[ "tab" ::: 'Table ('[] :=>
72+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
73+ , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[] '[]
132 manipulation =
74 manipulation =
133− insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))
75+ insertRow_ #tab (Set 2 `As` #col1 :* Default `As` #col2 :* Nil)
134in printSQL manipulation
76in printSQL manipulation
135:}
77:}
136INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)
78INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)
137
79
138parameterized insert:
80parameterized insert:
139
81
140−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]
141−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
142>>> :{
82>>> :{
143let
83let
144− manipulation :: Manipulation_ (Public Schema) (Int32, Int32) ()
84+ manipulation :: Manipulation
85+ '[ "tab" ::: 'Table ('[] :=>
86+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
87+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
88+ '[ 'NotNull 'PGint4, 'NotNull 'PGint4 ] '[]
145 manipulation =
89 manipulation =
90+ insertRow_ #tab
146− insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))
91+ (Set (param @1) `As` #col1 :* Set (param @2) `As` #col2 :* Nil)
147in printSQL manipulation
92in printSQL manipulation
148:}
93:}
149INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))
94INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))
@@ -152,48 +97,71 @@ returning insert:
152
97
153>>> :{
98>>> :{
154let
99let
155− manipulation :: Manipulation_ (Public Schema) () (Only Int32)
100+ manipulation :: Manipulation
101+ '[ "tab" ::: 'Table ('[] :=>
102+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
103+ , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[]
104+ '["fromOnly" ::: 'NotNull 'PGint4]
156 manipulation =
105 manipulation =
157− insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))
106+ insertRow #tab (Set 2 `As` #col1 :* Default `As` #col2 :* Nil)
158− OnConflictDoRaise (Returning (#col1 `as` #fromOnly))
107+ OnConflictDoRaise (Returning (#col1 `As` #fromOnly :* Nil))
159in printSQL manipulation
108in printSQL manipulation
160:}
109:}
161−INSERT INTO "tab" ("col1", "col2") VALUES (2, 3) RETURNING "col1" AS "fromOnly"
110+INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT) RETURNING "col1" AS "fromOnly"
162
111
163upsert:
112upsert:
164
113
165−>>> type CustomersColumns = '["name" ::: 'NoDef :=> 'NotNull 'PGtext, "email" ::: 'NoDef :=> 'NotNull 'PGtext]
166−>>> type CustomersConstraints = '["uq" ::: 'Unique '["name"]]
167−>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]
168>>> :{
114>>> :{
169let
115let
170− manipulation :: Manipulation_ (Public CustomersSchema) () ()
116+ manipulation :: Manipulation
117+ '[ "tab" ::: 'Table ('[] :=>
118+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
119+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
120+ '[] '[ "sum" ::: 'NotNull 'PGint4]
171 manipulation =
121 manipulation =
172− insertInto #customers
122+ insertRows #tab
173− (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))
123+ (Set 2 `As` #col1 :* Set 4 `As` #col2 :* Nil)
174− (OnConflict (OnConstraint #uq)
124+ [Set 6 `As` #col1 :* Set 8 `As` #col2 :* Nil]
175− (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))
125+ (OnConflictDoUpdate
176− (Returning_ Nil)
126+ (Set 2 `As` #col1 :* Same `As` #col2 :* Nil)
127+ [#col1 .== #col2])
128+ (Returning $ (#col1 + #col2) `As` #sum :* Nil)
177in printSQL manipulation
129in printSQL manipulation
178:}
130:}
179−INSERT INTO "customers" ("name", "email") VALUES (E'John Smith', E'john@smith.com') ON CONFLICT ON CONSTRAINT "uq" DO UPDATE SET "email" = ("excluded"."email" || (E'; ' || "customers"."email"))
131+INSERT INTO "tab" ("col1", "col2") VALUES (2, 4), (6, 8) ON CONFLICT DO UPDATE SET "col1" = 2 WHERE ("col1" = "col2") RETURNING ("col1" + "col2") AS "sum"
180
132
181query insert:
133query insert:
182
134
183>>> :{
135>>> :{
184let
136let
185− manipulation :: Manipulation_ (Public Schema) () ()
137+ manipulation :: Manipulation
186− manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))
138+ '[ "tab" ::: 'Table ('[] :=>
139+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
140+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4
141+ ])
142+ , "other_tab" ::: 'Table ('[] :=>
143+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
144+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4
145+ ])
146+ ] '[] '[]
147+ manipulation =
148+ insertQuery_ #tab
149+ (selectStar (from (table (#other_tab `As` #t))))
187in printSQL manipulation
150in printSQL manipulation
188:}
151:}
189−INSERT INTO "tab" SELECT * FROM "tab" AS "tab"
152+INSERT INTO "tab" SELECT * FROM "other_tab" AS "t"
190
153
191update:
154update:
192
155
193>>> :{
156>>> :{
194let
157let
195− manipulation :: Manipulation_ (Public Schema) () ()
158+ manipulation :: Manipulation
159+ '[ "tab" ::: 'Table ('[] :=>
160+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
161+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[] '[]
162+ manipulation =
196− manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)
163+ update_ #tab (Set 2 `As` #col1 :* Same `As` #col2 :* Nil)
164+ (#col1 ./= #col2)
197in printSQL manipulation
165in printSQL manipulation
198:}
166:}
199UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")
167UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")
@@ -202,178 +170,154 @@ delete:
202
170
203>>> :{
171>>> :{
204let
172let
205− manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)
173+ manipulation :: Manipulation
174+ '[ "tab" ::: 'Table ('[] :=>
175+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
176+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[]
177+ '[ "col1" ::: 'NotNull 'PGint4
178+ , "col2" ::: 'NotNull 'PGint4 ]
206− manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)
179+ manipulation = deleteFrom #tab (#col1 .== #col2) ReturningStar
207in printSQL manipulation
180in printSQL manipulation
208:}
181:}
209DELETE FROM "tab" WHERE ("col1" = "col2") RETURNING *
182DELETE FROM "tab" WHERE ("col1" = "col2") RETURNING *
210−
211−delete and using clause:
212−
213−>>> :{
214−type Schema3 =
215− '[ "tab" ::: 'Table ('[] :=> Columns)
216− , "other_tab" ::: 'Table ('[] :=> Columns)
217− , "third_tab" ::: 'Table ('[] :=> Columns) ]
218−:}
219−
220−>>> :{
221−let
222− manipulation :: Manipulation_ (Public Schema3) () ()
223− manipulation =
224− deleteFrom #tab (Using (table #other_tab & also (table #third_tab)))
225− ( (#tab ! #col2 .== #other_tab ! #col2)
226− .&& (#tab ! #col2 .== #third_tab ! #col2) )
227− (Returning_ Nil)
228−in printSQL manipulation
229−:}
230−DELETE FROM "tab" USING "other_tab" AS "other_tab", "third_tab" AS "third_tab" WHERE (("tab"."col2" = "other_tab"."col2") AND ("tab"."col2" = "third_tab"."col2"))
231−
232−with manipulation:
233−
234−>>> type ProductsColumns = '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]
235−>>> type ProductsSchema = '["products" ::: 'Table ('[] :=> ProductsColumns), "products_deleted" ::: 'Table ('[] :=> ProductsColumns)]
236−>>> :{
237−let
238− manipulation :: Manipulation_ (Public ProductsSchema) (Only Day) ()
239− manipulation = with
240− (deleteFrom #products NoUsing (#date .< param @1) (Returning Star) `as` #del)
241− (insertInto_ #products_deleted (Subquery (select Star (from (common #del)))))
242−in printSQL manipulation
243−:}
244−WITH "del" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "del" AS "del"
245-}
183-}
246−type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where
184+newtype Manipulation
247− Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)
185+ (schema :: SchemaType)
186+ (params :: [NullityType])
187+ (columns :: RelationType)
188+ = UnsafeManipulation { renderManipulation :: ByteString }
189+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
190+
191+instance RenderSQL (Manipulation schema params columns) where
192+ renderSQL = renderManipulation
248
193
249-- | Convert a `Query` into a `Manipulation`.
194-- | Convert a `Query` into a `Manipulation`.
250queryStatement
195queryStatement
251− :: Query '[] commons schemas params columns
196+ :: Query schema params columns
252− -- ^ `Query` to embed as a `Manipulation`
253− -> Manipulation commons schemas params columns
197+ -> Manipulation schema params columns
254−queryStatement q = UnsafeManipulation $ renderSQL q
198+queryStatement q = UnsafeManipulation $ renderQuery q
255
199
256{-----------------------------------------
200{-----------------------------------------
257INSERT statements
201INSERT statements
258-----------------------------------------}
202-----------------------------------------}
259
203
260−{- |
204+-- | Insert multiple rows.
205+--
261−When a table is created, it contains no data. The first thing to do
206+-- When a table is created, it contains no data. The first thing to do
262−before a database can be of much use is to insert data. Data is
207+-- before a database can be of much use is to insert data. Data is
263−conceptually inserted one row at a time. Of course you can also insert
208+-- conceptually inserted one row at a time. Of course you can also insert
264−more than one row, but there is no way to insert less than one row.
209+-- more than one row, but there is no way to insert less than one row.
265−Even if you know only some column values, a complete row must be created.
210+-- Even if you know only some column values, a complete row must be created.
266−-}
211+insertRows
267−insertInto
268− :: ( Has sch schemas schema
269− , Has tab schema ('Table table)
270− , columns ~ TableToColumns table
271− , row0 ~ TableToRow table
272− , SOP.SListI columns
212+ :: ( SOP.SListI columns
273− , SOP.SListI row1 )
213+ , SOP.SListI results
274− => QualifiedAlias sch tab
275− -- ^ table
276− -> QueryClause commons schemas params columns
277− -- ^ what to insert
278− -> ConflictClause tab commons schemas params table
279− -- ^ what to do in case of conflict
280− -> ReturningClause commons schemas params '[tab ::: row0] row1
281− -- ^ what to return
282− -> Manipulation commons schemas params row1
283−insertInto tab qry conflict ret = UnsafeManipulation $
284− "INSERT" <+> "INTO" <+> renderSQL tab
285− <+> renderSQL qry
286− <> renderSQL conflict
287− <> renderSQL ret
288−
289−-- | Like `insertInto` but with `OnConflictDoRaise` and `no` `ReturningClause`.
290−insertInto_
291− :: ( Has sch schemas schema
292 , Has tab schema ('Table table)
214 , Has tab schema ('Table table)
293− , columns ~ TableToColumns table
215+ , columns ~ TableToColumns table )
294− , row ~ TableToRow table
295− , SOP.SListI columns )
296− => QualifiedAlias sch tab
297− -- ^ table
298− -> QueryClause commons schemas params columns
299− -- ^ what to insert
216+ => Alias tab -- ^ table to insert into
300− -> Manipulation commons schemas params '[]
217+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
301−insertInto_ tab qry =
218+ -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert
302− insertInto tab qry OnConflictDoRaise (Returning_ Nil)
219+ -> ConflictClause schema columns params
303−
220+ -- ^ what to do in case of constraint conflict
304−-- | A `QueryClause` describes what to `insertInto` a table.
221+ -> ReturningClause schema columns params results -- ^ results to return
305−data QueryClause commons schemas params columns where
222+ -> Manipulation schema params results
306− Values
223+insertRows tab rw rws conflict returning = UnsafeManipulation $
307− :: SOP.SListI columns
224+ "INSERT" <+> "INTO" <+> renderAlias tab
308− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns
309− -- ^ row of values
310− -> [NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns]
311− -- ^ additional rows of values
312− -> QueryClause commons schemas params columns
313− Select
314− :: SOP.SListI columns
315− => NP (Aliased (Optional (Expression '[] commons grp schemas params from))) columns
316− -- ^ row of values
317− -> TableExpression '[] commons grp schemas params from
318− -- ^ from a table expression
319− -> QueryClause commons schemas params columns
320− Subquery
321− :: ColumnsToRow columns ~ row
322− => Query '[] commons schemas params row
323− -- ^ subquery to insert
324− -> QueryClause commons schemas params columns
325−
326−instance RenderSQL (QueryClause commons schemas params columns) where
327− renderSQL = \case
328− Values row0 rows ->
329− parenthesized (renderCommaSeparated renderSQLPart row0)
225+ <+> parenthesized (renderCommaSeparated renderAliasPart rw)
330− <+> "VALUES"
226+ <+> "VALUES"
331− <+> commaSeparated
227+ <+> commaSeparated
332− ( parenthesized
228+ ( parenthesized
333− . renderCommaSeparated renderValuePart <$> row0 : rows )
229+ . renderCommaSeparated renderColumnValuePart <$> rw:rws )
334− Select row0 tab ->
230+ <> renderConflictClause conflict
335− parenthesized (renderCommaSeparatedMaybe renderSQLPartMaybe row0)
231+ <> renderReturningClause returning
336− <+> "SELECT"
337− <+> renderCommaSeparatedMaybe renderValuePartMaybe row0
338− <+> renderSQL tab
339− Subquery qry -> renderQuery qry
340 where
232 where
341− renderSQLPartMaybe, renderValuePartMaybe
233+ renderAliasPart, renderColumnValuePart
342− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
234+ :: Aliased (ColumnValue schema '[] params) ty -> ByteString
343− -> Maybe ByteString
235+ renderAliasPart (_ `As` name) = renderAlias name
344− renderSQLPartMaybe = \case
236+ renderColumnValuePart (value `As` _) = case value of
345− Default `As` _ -> Nothing
346− Set _ `As` name -> Just $ renderSQL name
347− renderValuePartMaybe = \case
348− Default `As` _ -> Nothing
237+ Default -> "DEFAULT"
349− Set value `As` _ -> Just $ renderExpression value
238+ Set expression -> renderExpression expression
350− renderSQLPart, renderValuePart
239+
351− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
240+-- | Insert a single row.
352− -> ByteString
241+insertRow
353− renderSQLPart (_ `As` name) = renderSQL name
242+ :: ( SOP.SListI columns
354− renderValuePart (value `As` _) = renderSQL value
243+ , SOP.SListI results
355−
244+ , Has tab schema ('Table table)
356−-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s
245+ , columns ~ TableToColumns table )
357−-- whose `ColumnsType` must match the tables'.
246+ => Alias tab -- ^ table to insert into
358−pattern Values_
247+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
359− :: SOP.SListI columns
248+ -> ConflictClause schema columns params
360− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns
249+ -- ^ what to do in case of constraint conflict
361− -- ^ row of values
250+ -> ReturningClause schema columns params results -- ^ results to return
362− -> QueryClause commons schemas params columns
251+ -> Manipulation schema params results
363−pattern Values_ vals = Values vals []
252+insertRow tab rw = insertRows tab rw []
364−
253+
365−-- | `Optional` is either `Default` or a value, parameterized by an appropriate
254+-- | Insert multiple rows returning `Nil` and raising an error on conflicts.
366−-- `ColumnConstraint`.
255+insertRows_
367−data Optional expr ty where
256+ :: ( SOP.SListI columns
368− -- | Use the `Default` value for a column.
257+ , Has tab schema ('Table table)
369− Default :: Optional expr ('Def :=> ty)
258+ , columns ~ TableToColumns table )
370− -- | `Set` a value for a column.
259+ => Alias tab -- ^ table to insert into
371− Set :: expr ty -> Optional expr (def :=> ty)
260+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
372−
261+ -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert
373−instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where
262+ -> Manipulation schema params '[]
374− renderSQL = \case
263+insertRows_ tab rw rws =
375− Default -> "DEFAULT"
264+ insertRows tab rw rws OnConflictDoRaise (Returning Nil)
376− Set expr -> renderSQL expr
265+
266+-- | Insert a single row returning `Nil` and raising an error on conflicts.
267+insertRow_
268+ :: ( SOP.SListI columns
269+ , Has tab schema ('Table table)
270+ , columns ~ TableToColumns table )
271+ => Alias tab -- ^ table to insert into
272+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
273+ -> Manipulation schema params '[]
274+insertRow_ tab rw = insertRow tab rw OnConflictDoRaise (Returning Nil)
275+
276+-- | Insert a `Query`.
277+insertQuery
278+ :: ( SOP.SListI columns
279+ , SOP.SListI results
280+ , Has tab schema ('Table table)
281+ , columns ~ TableToColumns table )
282+ => Alias tab -- ^ table to insert into
283+ -> Query schema params (ColumnsToRelation columns)
284+ -> ConflictClause schema columns params
285+ -- ^ what to do in case of constraint conflict
286+ -> ReturningClause schema columns params results -- ^ results to return
287+ -> Manipulation schema params results
288+insertQuery tab query conflict returning = UnsafeManipulation $
289+ "INSERT" <+> "INTO" <+> renderAlias tab
290+ <+> renderQuery query
291+ <> renderConflictClause conflict
292+ <> renderReturningClause returning
293+
294+-- | Insert a `Query` returning `Nil` and raising an error on conflicts.
295+insertQuery_
296+ :: ( SOP.SListI columns
297+ , Has tab schema ('Table table)
298+ , columns ~ TableToColumns table )
299+ => Alias tab -- ^ table to insert into
300+ -> Query schema params (ColumnsToRelation columns)
301+ -> Manipulation schema params '[]
302+insertQuery_ tab query =
303+ insertQuery tab query OnConflictDoRaise (Returning Nil)
304+
305+-- | `ColumnValue`s are values to insert or update in a row.
306+-- `Same` updates with the same value.
307+-- `Default` inserts or updates with the @DEFAULT@ value.
308+-- `Set` sets a value to be an `Expression`, which can refer to
309+-- existing value in the row for an update.
310+data ColumnValue
311+ (schema :: SchemaType)
312+ (columns :: RelationType)
313+ (params :: [NullityType])
314+ (ty :: ColumnType)
315+ where
316+ Same :: ColumnValue schema (column ': columns) params ty
317+ Default :: ColumnValue schema columns params ('Def :=> ty)
318+ Set
319+ :: (forall table. Expression schema '[table ::: columns] 'Ungrouped params ty)
320+ -> ColumnValue schema columns params (constraint :=> ty)
377
321
378-- | A `ReturningClause` computes and return value(s) based
322-- | A `ReturningClause` computes and return value(s) based
379-- on each row actually inserted, updated or deleted. This is primarily
323-- on each row actually inserted, updated or deleted. This is primarily
@@ -381,100 +325,72 @@ instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where
381-- serial sequence number. However, any expression using the table's columns
325-- serial sequence number. However, any expression using the table's columns
382-- is allowed. Only rows that were successfully inserted or updated or
326-- is allowed. Only rows that were successfully inserted or updated or
383-- deleted will be returned. For example, if a row was locked
327-- deleted will be returned. For example, if a row was locked
384−-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,
328+-- but not updated because an `OnConflictDoUpdate` condition was not satisfied,
385−-- the row will not be returned. `Returning` `Star` will return all columns
329+-- the row will not be returned. `ReturningStar` will return all columns
386−-- in the row. Use `Returning` `Nil` in the common case where no return
330+-- in the row. Use @Returning Nil@ in the common case where no return
387-- values are desired.
331-- values are desired.
388−newtype ReturningClause commons schemas params from row =
332+data ReturningClause
389− Returning (Selection '[] commons 'Ungrouped schemas params from row)
333+ (schema :: SchemaType)
390−
334+ (columns :: ColumnsType)
391−instance RenderSQL (ReturningClause commons schemas params from row) where
335+ (params :: [NullityType])
392− renderSQL = \case
336+ (results :: RelationType)
393− Returning (List Nil) -> ""
337+ where
394− Returning selection -> " RETURNING" <+> renderSQL selection
338+ ReturningStar
395−
339+ :: results ~ ColumnsToRelation columns
396−-- | `Returning` a `List`
340+ => ReturningClause schema columns params results
397−pattern Returning_
341+ Returning
342+ :: rel ~ ColumnsToRelation columns
343+ => NP (Aliased (Expression schema '[table ::: rel] 'Ungrouped params)) results
344+ -> ReturningClause schema columns params results
345+
346+-- | Render a `ReturningClause`.
347+renderReturningClause
398− :: SOP.SListI row
348+ :: SOP.SListI results
399− => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row
349+ => ReturningClause schema params columns results
400− -- ^ row of values
350+ -> ByteString
401− -> ReturningClause commons schemas params from row
351+renderReturningClause = \case
402−pattern Returning_ list = Returning (List list)
352+ ReturningStar -> " RETURNING *"
353+ Returning Nil -> ""
354+ Returning results -> " RETURNING"
355+ <+> renderCommaSeparated (renderAliasedAs renderExpression) results
403
356
404-- | A `ConflictClause` specifies an action to perform upon a constraint
357-- | A `ConflictClause` specifies an action to perform upon a constraint
405-- violation. `OnConflictDoRaise` will raise an error.
358-- violation. `OnConflictDoRaise` will raise an error.
406−-- `OnConflict` `DoNothing` simply avoids inserting a row.
359+-- `OnConflictDoNothing` simply avoids inserting a row.
407−-- `OnConflict` `DoUpdate` updates the existing row that conflicts with the row
360+-- `OnConflictDoUpdate` updates the existing row that conflicts with the row
408-- proposed for insertion.
361-- proposed for insertion.
409−data ConflictClause tab commons schemas params table where
362+data ConflictClause (schema :: SchemaType) (columns :: ColumnsType) params where
410− OnConflictDoRaise :: ConflictClause tab commons schemas params table
363+ OnConflictDoRaise :: ConflictClause schema columns params
411− OnConflict
364+ OnConflictDoNothing :: ConflictClause schema columns params
412− :: ConflictTarget constraints
365+ OnConflictDoUpdate
413− -- ^ conflict target
366+ :: NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
414− -> ConflictAction tab commons schemas params columns
367+ -> [Condition schema '[table ::: ColumnsToRelation columns] 'Ungrouped params]
415− -- ^ conflict action
368+ -> ConflictClause schema columns params
416− -> ConflictClause tab commons schemas params (constraints :=> columns)
417
369
418-- | Render a `ConflictClause`.
370-- | Render a `ConflictClause`.
419−instance SOP.SListI (TableToColumns table)
371+renderConflictClause
420− => RenderSQL (ConflictClause tab commons schemas params table) where
372+ :: SOP.SListI columns
421− renderSQL = \case
373+ => ConflictClause schema columns params
422− OnConflictDoRaise -> ""
423− OnConflict target action -> " ON CONFLICT"
424− <+> renderSQL target <+> renderSQL action
425−
426−{- |
427−`ConflictAction` specifies an alternative `OnConflict` action.
428−It can be either `DoNothing`, or a `DoUpdate` clause specifying
429−the exact details of the `update` action to be performed in case of a conflict.
430−The `Set` and WHERE `Condition`s in `OnConflict` `DoUpdate` have access to the
431−existing row using the table's name (or an alias), and to rows proposed
432−for insertion using the special @#excluded@ table.
433−`OnConflict` `DoNothing` simply avoids inserting a row as its alternative action.
434−`OnConflict` `DoUpdate` updates the existing row that conflicts
435−with the row proposed for insertion as its alternative action.
436−-}
437−data ConflictAction tab commons schemas params columns where
438− DoNothing :: ConflictAction tab commons schemas params columns
439− DoUpdate
440− :: ( row ~ ColumnsToRow columns
441− , SOP.SListI columns
442− , columns ~ (col0 ': cols)
443− , SOP.All (HasIn columns) subcolumns
444− , AllUnique subcolumns )
445− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]))) subcolumns
446− -> [Condition '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]]
447− -- ^ WHERE `Condition`s
448− -> ConflictAction tab commons schemas params columns
449−
450−instance RenderSQL (ConflictAction tab commons schemas params columns) where
451− renderSQL = \case
452− DoNothing -> "DO NOTHING"
453− DoUpdate updates whs'
454− -> "DO UPDATE SET"
455− <+> renderCommaSeparated renderUpdate updates
456− <> case whs' of
457− [] -> ""
458− wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)
459−
460−renderUpdate
461− :: (forall x. RenderSQL (expr x))
462− => Aliased (Optional expr) ty
463 -> ByteString
374 -> ByteString
464−renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr
375+renderConflictClause = \case
465−
376+ OnConflictDoRaise -> ""
466−-- | A `ConflictTarget` specifies the constraint violation that triggers a
377+ OnConflictDoNothing -> " ON CONFLICT DO NOTHING"
467−-- `ConflictAction`.
378+ OnConflictDoUpdate updates whs'
468−data ConflictTarget constraints where
379+ -> " ON CONFLICT DO UPDATE SET"
469− OnConstraint
380+ <+> renderCommaSeparatedMaybe renderUpdate updates
470− :: Has con constraints constraint
381+ <> case whs' of
471− => Alias con
382+ [] -> ""
472− -> ConflictTarget constraints
383+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)
473−
384+ where
474−-- | Render a `ConflictTarget`
385+ renderUpdate
475−instance RenderSQL (ConflictTarget constraints) where
386+ :: Aliased (ColumnValue schema columns params) column
476− renderSQL (OnConstraint con) =
387+ -> Maybe ByteString
477− "ON" <+> "CONSTRAINT" <+> renderSQL con
388+ renderUpdate = \case
389+ Same `As` _ -> Nothing
390+ Default `As` column -> Just $
391+ renderAlias column <+> "=" <+> "DEFAULT"
392+ Set expression `As` column -> Just $
393+ renderAlias column <+> "=" <+> renderExpression expression
478
394
479{-----------------------------------------
395{-----------------------------------------
480UPDATE statements
396UPDATE statements
@@ -484,95 +400,108 @@ UPDATE statements
484-- in all rows that satisfy the condition.
400-- in all rows that satisfy the condition.
485update
401update
486 :: ( SOP.SListI columns
402 :: ( SOP.SListI columns
487− , SOP.SListI row1
403+ , SOP.SListI results
488− , Has sch schemas schema
489 , Has tab schema ('Table table)
404 , Has tab schema ('Table table)
490− , row0 ~ TableToRow table
491− , columns ~ TableToColumns table
405+ , columns ~ TableToColumns table )
492− , SOP.All (HasIn columns) subcolumns
493− , AllUnique subcolumns )
494− => QualifiedAlias sch tab -- ^ table to update
406+ => Alias tab -- ^ table to update
495− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns
407+ -> NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
496 -- ^ modified values to replace old values
408 -- ^ modified values to replace old values
497− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]
409+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
498 -- ^ condition under which to perform update on a row
410 -- ^ condition under which to perform update on a row
499− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
411+ -> ReturningClause schema columns params results -- ^ results to return
500− -> Manipulation commons schemas params row1
412+ -> Manipulation schema params results
501update tab columns wh returning = UnsafeManipulation $
413update tab columns wh returning = UnsafeManipulation $
502 "UPDATE"
414 "UPDATE"
503− <+> renderSQL tab
415+ <+> renderAlias tab
504 <+> "SET"
416 <+> "SET"
505− <+> renderCommaSeparated renderUpdate columns
417+ <+> renderCommaSeparatedMaybe renderUpdate columns
506− <+> "WHERE" <+> renderSQL wh
418+ <+> "WHERE" <+> renderExpression wh
507− <> renderSQL returning
419+ <> renderReturningClause returning
420+ where
421+ renderUpdate
422+ :: Aliased (ColumnValue schema columns params) column
423+ -> Maybe ByteString
424+ renderUpdate = \case
425+ Same `As` _ -> Nothing
426+ Default `As` column -> Just $
427+ renderAlias column <+> "=" <+> "DEFAULT"
428+ Set expression `As` column -> Just $
429+ renderAlias column <+> "=" <+> renderExpression expression
508
430
509-- | Update a row returning `Nil`.
431-- | Update a row returning `Nil`.
510update_
432update_
511 :: ( SOP.SListI columns
433 :: ( SOP.SListI columns
512− , Has sch schemas schema
513 , Has tab schema ('Table table)
434 , Has tab schema ('Table table)
514− , row ~ TableToRow table
515− , columns ~ TableToColumns table
435+ , columns ~ TableToColumns table )
516− , SOP.All (HasIn columns) subcolumns
517− , AllUnique subcolumns )
518− => QualifiedAlias sch tab -- ^ table to update
436+ => Alias tab -- ^ table to update
519− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns
437+ -> NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
520 -- ^ modified values to replace old values
438 -- ^ modified values to replace old values
521− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
439+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
522 -- ^ condition under which to perform update on a row
440 -- ^ condition under which to perform update on a row
523− -> Manipulation commons schemas params '[]
441+ -> Manipulation schema params '[]
524−update_ tab columns wh = update tab columns wh (Returning_ Nil)
442+update_ tab columns wh = update tab columns wh (Returning Nil)
525
443
526{-----------------------------------------
444{-----------------------------------------
527DELETE statements
445DELETE statements
528-----------------------------------------}
446-----------------------------------------}
529
447
530−-- | Specify additional tables with `Using`
531−-- an `also` list of table expressions, allowing columns
532−-- from other tables to appear in the WHERE condition.
533−-- This is similar to the list of tables that can be specified
534−-- in the FROM Clause of a SELECT statement;
535−-- for example, an alias for the table name can be specified.
536−-- Do not repeat the target table in the `Using` list,
537−-- unless you wish to set up a self-join.
538−-- `NoUsing` if no additional tables are to be used.
539−data UsingClause commons schemas params from where
540− NoUsing :: UsingClause commons schemas params '[]
541− Using
542− :: FromClause '[] commons schemas params from
543− -- ^ what to use
544− -> UsingClause commons schemas params from
545−
546−-- | Delete rows from a table.
448+-- | Delete rows of a table.
547deleteFrom
449deleteFrom
548− :: ( SOP.SListI row1
450+ :: ( SOP.SListI results
549− , Has sch schemas schema
550 , Has tab schema ('Table table)
451 , Has tab schema ('Table table)
551− , row0 ~ TableToRow table
552 , columns ~ TableToColumns table )
452 , columns ~ TableToColumns table )
553− => QualifiedAlias sch tab -- ^ table to delete from
453+ => Alias tab -- ^ table to delete from
554− -> UsingClause commons schemas params from
555− -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)
454+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
556 -- ^ condition under which to delete a row
455 -- ^ condition under which to delete a row
557− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
456+ -> ReturningClause schema columns params results -- ^ results to return
558− -> Manipulation commons schemas params row1
457+ -> Manipulation schema params results
559−deleteFrom tab using wh returning = UnsafeManipulation $
458+deleteFrom tab wh returning = UnsafeManipulation $
560− "DELETE FROM"
459+ "DELETE FROM" <+> renderAlias tab
561− <+> renderSQL tab
460+ <+> "WHERE" <+> renderExpression wh
562− <> case using of
461+ <> renderReturningClause returning
563− NoUsing -> ""
564− Using tables -> " USING" <+> renderSQL tables
565− <+> "WHERE" <+> renderSQL wh
566− <> renderSQL returning
567
462
568-- | Delete rows returning `Nil`.
463-- | Delete rows returning `Nil`.
569deleteFrom_
464deleteFrom_
570− :: ( Has sch schemas schema
571− , Has tab schema ('Table table)
465+ :: ( Has tab schema ('Table table)
572− , row ~ TableToRow table
573 , columns ~ TableToColumns table )
466 , columns ~ TableToColumns table )
574− => QualifiedAlias sch tab -- ^ table to delete from
467+ => Alias tab -- ^ table to delete from
575− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
468+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
576 -- ^ condition under which to delete a row
469 -- ^ condition under which to delete a row
577− -> Manipulation commons schemas params '[]
470+ -> Manipulation schema params '[]
578−deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)
471+deleteFrom_ tab wh = deleteFrom tab wh (Returning Nil)
472+
473+{-----------------------------------------
474+WITH statements
475+-----------------------------------------}
476+
477+-- | `with` provides a way to write auxiliary statements for use in a larger statement.
478+-- These statements, which are often referred to as Common Table Expressions or CTEs,
479+-- can be thought of as defining temporary tables that exist just for one statement.
480+--
481+-- >>> type ProductsTable = '[] :=> '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]
482+--
483+-- >>> :{
484+-- let
485+-- manipulation :: Manipulation '["products" ::: 'Table ProductsTable, "products_deleted" ::: 'Table ProductsTable] '[ 'NotNull 'PGdate] '[]
486+-- manipulation = with
487+-- (deleteFrom #products (#date .< param @1) ReturningStar `As` #deleted_rows :* Nil)
488+-- (insertQuery_ #products_deleted (selectStar (from (view (#deleted_rows `As` #t)))))
489+-- in printSQL manipulation
490+-- :}
491+-- WITH "deleted_rows" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "deleted_rows" AS "t"
492+with
493+ :: SOP.SListI commons
494+ => NP (Aliased (Manipulation schema params)) commons
495+ -- ^ common table expressions
496+ -> Manipulation (With commons schema) params results
497+ -> Manipulation schema params results
498+with commons manipulation = UnsafeManipulation $
499+ "WITH" <+> renderCommaSeparated renderCommon commons
500+ <+> renderManipulation manipulation
501+ where
502+ renderCommon
503+ :: Aliased (Manipulation schema params) common
504+ -> ByteString
505+ renderCommon (common `As` alias) =
506+ renderAlias alias <+> "AS" <+>
507+ parenthesized (renderManipulation common)
squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+215−347
@@ -8,13 +8,8 @@ Stability: experimental
8This module defines a `Migration` type to safely
8This module defines a `Migration` type to safely
9change the schema of your database over time. Let's see an example!
9change the schema of your database over time. Let's see an example!
10
10
11−First turn on some extensions.
12−
13>>> :set -XDataKinds -XOverloadedLabels
11>>> :set -XDataKinds -XOverloadedLabels
14>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators
12>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators
15−
16−Next, let's define our `TableType`s.
17−
18>>> :{
13>>> :{
19type UsersTable =
14type UsersTable =
20 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
15 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
@@ -25,7 +20,7 @@ type UsersTable =
25
20
26>>> :{
21>>> :{
27type EmailsTable =
22type EmailsTable =
28− '[ "pk_emails" ::: 'PrimaryKey '["id"]
23+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
29 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
24 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
30 ] :=>
25 ] :=>
31 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
26 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
@@ -34,293 +29,248 @@ type EmailsTable =
34 ]
29 ]
35:}
30:}
36
31
37−Now we can define some `Migration`s to make our tables.
38−
39>>> :{
32>>> :{
40let
33let
41− makeUsers :: Migration Definition (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]
34+ makeUsers :: Migration IO '[] '["users" ::: 'Table UsersTable]
42 makeUsers = Migration
35 makeUsers = Migration
43 { name = "make users table"
36 { name = "make users table"
37+ , up = void . define $
44− , up = createTable #users
38+ createTable #users
45− ( serial `as` #id :*
39+ ( serial `As` #id :*
46− notNullable text `as` #name )
40+ (text & notNullable) `As` #name :* Nil )
47− ( primaryKey #id `as` #pk_users )
41+ ( primaryKey #id `As` #pk_users :* Nil )
48− , down = dropTable #users
42+ , down = void . define $ dropTable #users
49 }
43 }
50:}
44:}
51
45
52>>> :{
46>>> :{
53let
47let
54− makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]
48+ makeEmails :: Migration IO '["users" ::: 'Table UsersTable]
55− '["public" ::: '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]]
49+ '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]
56 makeEmails = Migration
50 makeEmails = Migration
57 { name = "make emails table"
51 { name = "make emails table"
52+ , up = void . define $
58− , up = createTable #emails
53+ createTable #emails
59− ( serial `as` #id :*
54+ ( serial `As` #id :*
60− notNullable int `as` #user_id :*
55+ (int & notNullable) `As` #user_id :*
61− nullable text `as` #email )
56+ (text & nullable) `As` #email :* Nil )
62− ( primaryKey #id `as` #pk_emails :*
57+ ( primaryKey #id `As` #pk_emails :*
63 foreignKey #user_id #users #id
58 foreignKey #user_id #users #id
64− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
59+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
65− , down = dropTable #emails
60+ , down = void . define $ dropTable #emails
66 }
61 }
67:}
62:}
68
63
69−Now that we have a couple migrations we can chain them together into a `Path`.
64+Now that we have a couple migrations we can chain them together.
70
65
71>>> let migrations = makeUsers :>> makeEmails :>> Done
66>>> let migrations = makeUsers :>> makeEmails :>> Done
72
67
73−Now run the migrations.
68+>>> :{
69+let
70+ numMigrations
71+ :: Has "schema_migrations" schema ('Table MigrationsTable)
72+ => PQ schema schema IO ()
73+ numMigrations = do
74+ result <- runQuery (selectStar (from (table (#schema_migrations `As` #m))))
75+ num <- ntuples result
76+ liftBase $ print num
77+:}
74
78
75−>>> import Control.Monad.IO.Class
76>>> :{
79>>> :{
77withConnection "host=localhost port=5432 dbname=exampledb" $
80withConnection "host=localhost port=5432 dbname=exampledb" $
78 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
81 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
79 -- suppress notices
82 -- suppress notices
80− & pqThen (liftIO (putStrLn "Migrate"))
81 & pqThen (migrateUp migrations)
83 & pqThen (migrateUp migrations)
82− & pqThen (liftIO (putStrLn "Rollback"))
84+ & pqThen numMigrations
83 & pqThen (migrateDown migrations)
85 & pqThen (migrateDown migrations)
86+ & pqThen numMigrations
84:}
87:}
85−Migrate
88+Row 2
86−Rollback
89+Row 0
87−
88−We can also create a simple executable using `defaultMain`.
89−
90−>>> let main = defaultMain "host=localhost port=5432 dbname=exampledb" migrations
91−
92−>>> withArgs [] main
93−Invalid command: "". Use:
94−migrate to run all available migrations
95−rollback to rollback all available migrations
96−status to display migrations run and migrations left to run
97−
98−>>> withArgs ["status"] main
99−Migrations already run:
100− None
101−Migrations left to run:
102− - make users table
103− - make emails table
104−
105−>>> withArgs ["migrate"] main
106−Migrations already run:
107− - make users table
108− - make emails table
109−Migrations left to run:
110− None
111−
112−>>> withArgs ["rollback"] main
113−Migrations already run:
114− None
115−Migrations left to run:
116− - make users table
117− - make emails table
118−
119−In addition to enabling `Migration`s using pure SQL `Definition`s for
120−the `up` and `down` instructions, you can also perform impure `IO` actions
121−by using a `Migration`s over the `Terminally` `PQ` `IO` category.
122-}
90-}
123
91
124{-# LANGUAGE
92{-# LANGUAGE
125 DataKinds
93 DataKinds
126− , DeriveGeneric
127− , FlexibleContexts
128− , FlexibleInstances
129 , GADTs
94 , GADTs
130 , LambdaCase
95 , LambdaCase
131− , OverloadedLabels
132− , OverloadedStrings
133 , PolyKinds
96 , PolyKinds
134− , QuantifiedConstraints
97+ , OverloadedLabels
135− , RankNTypes
136 , TypeApplications
98 , TypeApplications
99+ , FlexibleContexts
137 , TypeOperators
100 , TypeOperators
138#-}
101#-}
139
102
140module Squeal.PostgreSQL.Migration
103module Squeal.PostgreSQL.Migration
141 ( -- * Migration
104 ( -- * Migration
142 Migration (..)
105 Migration (..)
143− , Migratory (..)
106+ , migrateUp
144− , Terminally (..)
107+ , migrateDown
145− , terminally
108+ -- * Aligned lists
146− , pureMigration
109+ , AlignedList (..)
110+ , single
111+ -- * Migration table
147 , MigrationsTable
112 , MigrationsTable
148− , defaultMain
113+ , createMigrations
114+ , insertMigration
115+ , deleteMigration
116+ , selectMigration
149 ) where
117 ) where
150
118
151import Control.Category
119import Control.Category
152import Control.Monad
120import Control.Monad
153−import Data.ByteString (ByteString)
121+import Control.Monad.Base
122+import Control.Monad.Trans.Control
154−import Data.Foldable (traverse_)
123+import Data.Monoid
124+import Generics.SOP (K(..))
155import Data.Function ((&))
125import Data.Function ((&))
156−import Data.List ((\\))
157import Data.Text (Text)
126import Data.Text (Text)
158−import Data.Time (UTCTime)
159−import Prelude hiding ((.), id)
127+import Prelude hiding (id, (.))
160−import System.Environment
161−import UnliftIO (MonadIO (..))
162−
163−import qualified Data.Text.IO as Text (putStrLn)
164−import qualified Generics.SOP as SOP
165−import qualified GHC.Generics as GHC
166
128
167−import Squeal.PostgreSQL.Alias
129+import Squeal.PostgreSQL
168−import Squeal.PostgreSQL.Binary
169−import Squeal.PostgreSQL.Definition
170−import Squeal.PostgreSQL.Definition.Table
171−import Squeal.PostgreSQL.Definition.Table.Constraint
172−import Squeal.PostgreSQL.Expression.Comparison
173−import Squeal.PostgreSQL.Expression.Parameter
174−import Squeal.PostgreSQL.Expression.Time
175−import Squeal.PostgreSQL.Expression.Type
176−import Squeal.PostgreSQL.List
177−import Squeal.PostgreSQL.Manipulation
178−import Squeal.PostgreSQL.PQ
179−import Squeal.PostgreSQL.Query
180−import Squeal.PostgreSQL.Schema
181−import Squeal.PostgreSQL.Transaction
182
130
183−-- | A `Migration` is a named "isomorphism" over a given category.
184−-- It should contain an inverse pair of `up` and `down`
131+-- | A `Migration` should contain an inverse pair of
185−-- instructions and a unique `name`.
132+-- `up` and `down` instructions and a unique `name`.
186−data Migration p schemas0 schemas1 = Migration
133+data Migration io schema0 schema1 = Migration
187 { name :: Text -- ^ The `name` of a `Migration`.
134 { name :: Text -- ^ The `name` of a `Migration`.
188 -- Each `name` in a `Migration` should be unique.
135 -- Each `name` in a `Migration` should be unique.
189− , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.
136+ , up :: PQ schema0 schema1 io () -- ^ The `up` instruction of a `Migration`.
190− , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.
137+ , down :: PQ schema1 schema0 io () -- ^ The `down` instruction of a `Migration`.
191− } deriving (GHC.Generic)
192−
193−{- |
194−A `Migratory` @p@ is a `Category` for which one can execute or rewind
195−a `Path` of `Migration`s over @p@. This includes the category of pure
196−SQL `Definition`s and the category of impure `Terminally` `PQ` `IO` actions.
197−-}
198−class Category p => Migratory p where
199−
200− {- |
201− Run a `Path` of `Migration`s.
202− Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.
203− In one transaction, for each each `Migration` query to see if the `Migration` has been executed;
204− if not, `up` the `Migration` and insert its `name` in the `MigrationsTable`.
205− -}
206− migrateUp
207− :: Path (Migration p) schemas0 schemas1
208− -> PQ schemas0 schemas1 IO ()
209−
210− {- |
211− Rewind a `Path` of `Migration`s.
212− Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.
213− In one transaction, for each each `Migration` query to see if the `Migration` has been executed;
214− if so, `down` the `Migration` and delete its `name` in the `MigrationsTable`.
215− -}
216− migrateDown
217− :: Path (Migration p) schemas0 schemas1
218− -> PQ schemas1 schemas0 IO ()
219−
220−instance Migratory Definition where
221− migrateUp = migrateUp . cmap pureMigration
222− migrateDown = migrateDown . cmap pureMigration
223−
224−{- | `Terminally` turns an indexed monad transformer and the monad it transforms
225−into a category by restricting the return type to @()@ and permuting the type variables.
226−This is similar to how applying a monad to @()@ yields a monoid.
227−Since a `Terminally` action has a trivial return value, the only reason
228−to run one is for the side effects, in particular database and other IO effects.
229−-}
230−newtype Terminally trans monad x0 x1 = Terminally
231− { runTerminally :: trans x0 x1 monad () }
232− deriving GHC.Generic
233−
234−instance
235− ( IndexedMonadTransPQ trans
236− , Monad monad
237− , forall x0 x1. x0 ~ x1 => Monad (trans x0 x1 monad) )
238− => Category (Terminally trans monad) where
239− id = Terminally (return ())
240− Terminally g . Terminally f = Terminally $ pqThen g f
241−
242−-- | `terminally` ignores the output of a computation, returning @()@ and
243−-- wrapping it up into a `Terminally`. You can lift an action in the base monad
244−-- by using @terminally . lift@.
245−terminally
246− :: Functor (trans x0 x1 monad)
247− => trans x0 x1 monad ignore
248− -> Terminally trans monad x0 x1
249−terminally = Terminally . void
250−
251−-- | A `pureMigration` turns a `Migration` involving only pure SQL
252−-- `Definition`s into a `Migration` that may be combined with arbitrary `IO`.
253−pureMigration
254− :: Migration Definition schemas0 schemas1
255− -> Migration (Terminally PQ IO) schemas0 schemas1
256−pureMigration migration = Migration
257− { name = name migration
258− , up = terminally . define $ up migration
259− , down = terminally . define $ down migration
260 }
138 }
261
139
262−instance Migratory (Terminally PQ IO) where
140+-- | An `AlignedList` is a type-aligned list or free category.
263−
141+data AlignedList p x0 x1 where
264− migrateUp migration = unsafePQ . transactionally_ $ do
142+ Done :: AlignedList p x x
265− define createMigrations
143+ (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2
266− upMigrations migration
144+infixr 7 :>>
267−
145+instance Category (AlignedList p) where
268− where
146+ id = Done
269−
147+ (.) list = \case
270− upMigrations
271− :: Path (Migration (Terminally PQ IO)) schemas0 schemas1
272− -> PQ MigrationsSchemas MigrationsSchemas IO ()
273− upMigrations = \case
274− Done -> return ()
148+ Done -> list
275− step :>> steps -> upMigration step >> upMigrations steps
149+ step :>> steps -> step :>> (steps >>> list)
276−
150+
277− upMigration
151+-- | A `single` step.
278− :: Migration (Terminally PQ IO) schemas0 schemas1
152+single :: p x0 x1 -> AlignedList p x0 x1
279− -> PQ MigrationsSchemas MigrationsSchemas IO ()
153+single step = step :>> Done
280− upMigration step = do
154+
281− executed <- queryExecuted step
155+-- | Run `Migration`s by creating the `MigrationsTable`
282− unless (executed == 1) $ do
156+-- if it does not exist and then in a transaction, for each each `Migration`
283− unsafePQ . runTerminally $ up step
157+-- query to see if the `Migration` is executed. If not, then
284− manipulateParams_ insertMigration (Only (name step))
158+-- execute the `Migration` and insert its row in the `MigrationsTable`.
285−
159+migrateUp
286− queryExecuted
160+ :: MonadBaseControl IO io
287− :: Migration (Terminally PQ IO) schemas0 schemas1
161+ => AlignedList (Migration io) schema0 schema1 -- ^ migrations to run
288− -> PQ MigrationsSchemas MigrationsSchemas IO Row
162+ -> PQ
289− queryExecuted step = do
163+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
290− result <- runQueryParams selectMigration (Only (name step))
164+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
291− ntuples result
165+ io ()
292−
166+migrateUp migration =
293− migrateDown migrations = unsafePQ . transactionally_ $ do
167+ define createMigrations
294− define createMigrations
168+ & pqBind okResult
295− downMigrations migrations
169+ & pqThen (transactionallySchema_ (upMigrations migration))
296−
170+ where
297− where
298−
299− downMigrations
300− :: Path (Migration (Terminally PQ IO)) schemas0 schemas1
301− -> PQ MigrationsSchemas MigrationsSchemas IO ()
302− downMigrations = \case
303− Done -> return ()
304− step :>> steps -> downMigrations steps >> downMigration step
305−
306− downMigration
307− :: Migration (Terminally PQ IO) schemas0 schemas1
308− -> PQ MigrationsSchemas MigrationsSchemas IO ()
309− downMigration step = do
310− executed <- queryExecuted step
311− unless (executed == 0) $ do
312− unsafePQ . runTerminally $ down step
313− manipulateParams_ deleteMigration (Only (name step))
314
171
315− queryExecuted
172+ upMigrations
316− :: Migration (Terminally PQ IO) schemas0 schemas1
173+ :: MonadBaseControl IO io
317− -> PQ MigrationsSchemas MigrationsSchemas IO Row
174+ => AlignedList (Migration io) schema0 schema1
175+ -> PQ
176+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
177+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
178+ io ()
179+ upMigrations = \case
180+ Done -> return ()
181+ step :>> steps -> upMigration step & pqThen (upMigrations steps)
182+
183+ upMigration
184+ :: MonadBase IO io
185+ => Migration io schema0 schema1 -> PQ
186+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
187+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
188+ io ()
189+ upMigration step =
190+ queryExecuted step
191+ & pqBind (\ executed ->
192+ if executed == 1 -- up step has already been executed
193+ then PQ (\ _ -> return (K ())) -- unsafely switch schemas
194+ else
195+ pqEmbed (up step) -- safely switch schemas
196+ & pqThen (manipulateParams insertMigration (Only (name step)))
197+ -- insert execution record
198+ & pqBind okResult)
199+
200+ queryExecuted
201+ :: MonadBase IO io
202+ => Migration io schema0 schema1 -> PQ
203+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
204+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
205+ io Row
318− queryExecuted step = do
206+ queryExecuted step = do
319− result <- runQueryParams selectMigration (Only (name step))
207+ result <- runQueryParams selectMigration (Only (name step))
208+ okResult result
320− ntuples result
209+ ntuples result
210+
211+-- | Rewind `Migration`s by creating the `MigrationsTable`
212+-- if it does not exist and then in a transaction, for each each `Migration`
213+-- query to see if the `Migration` is executed. If it is, then
214+-- rewind the `Migration` and delete its row in the `MigrationsTable`.
215+migrateDown
216+ :: MonadBaseControl IO io
217+ => AlignedList (Migration io) schema0 schema1 -- ^ migrations to rewind
218+ -> PQ
219+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
220+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
221+ io ()
222+migrateDown migrations =
223+ define createMigrations
224+ & pqBind okResult
225+ & pqThen (transactionallySchema_ (downMigrations migrations))
226+ where
321
227
322−unsafePQ :: (Functor m) => PQ db0 db1 m x -> PQ db0' db1' m x
228+ downMigrations
323−unsafePQ (PQ pq) = PQ $ fmap (SOP.K . SOP.unK) . pq . SOP.K . SOP.unK
229+ :: MonadBaseControl IO io
230+ => AlignedList (Migration io) schema0 schema1 -> PQ
231+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
232+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
233+ io ()
234+ downMigrations = \case
235+ Done -> return ()
236+ step :>> steps -> downMigrations steps & pqThen (downMigration step)
237+
238+ downMigration
239+ :: MonadBase IO io
240+ => Migration io schema0 schema1 -> PQ
241+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
242+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
243+ io ()
244+ downMigration step =
245+ queryExecuted step
246+ & pqBind (\ executed ->
247+ if executed == 0 -- up step has not been executed
248+ then PQ (\ _ -> return (K ())) -- unsafely switch schemas
249+ else
250+ pqEmbed (down step) -- safely switch schemas
251+ & pqThen (manipulateParams deleteMigration (Only (name step)))
252+ -- delete execution record
253+ & pqBind okResult)
254+
255+ queryExecuted
256+ :: MonadBase IO io
257+ => Migration io schema0 schema1 -> PQ
258+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
259+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
260+ io Row
261+ queryExecuted step = do
262+ result <- runQueryParams selectMigration (Only (name step))
263+ okResult result
264+ ntuples result
265+
266+okResult :: MonadBase IO io => K Result results -> PQ schema schema io ()
267+okResult result = do
268+ status <- resultStatus result
269+ when (not (status `elem` [CommandOk, TuplesOk])) $ do
270+ errorMessageMaybe <- resultErrorMessage result
271+ case errorMessageMaybe of
272+ Nothing -> error "migrateDown: unknown error"
273+ Just msg -> error ("migrationDown: " <> show msg)
324
274
325-- | The `TableType` for a Squeal migration.
275-- | The `TableType` for a Squeal migration.
326type MigrationsTable =
276type MigrationsTable =
@@ -329,120 +279,38 @@ type MigrationsTable =
329 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz
279 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz
330 ]
280 ]
331
281
332−data MigrationRow =
333− MigrationRow { migrationName :: Text
334− , migrationTime :: UTCTime }
335− deriving (GHC.Generic, Show)
336−
337−instance SOP.Generic MigrationRow
338−instance SOP.HasDatatypeInfo MigrationRow
339−
340−type MigrationsSchema = '["schema_migrations" ::: 'Table MigrationsTable]
341−type MigrationsSchemas = Public MigrationsSchema
342−
343-- | Creates a `MigrationsTable` if it does not already exist.
282-- | Creates a `MigrationsTable` if it does not already exist.
344−createMigrations :: Definition MigrationsSchemas MigrationsSchemas
283+createMigrations
284+ :: Has "schema_migrations" schema ('Table MigrationsTable)
285+ => Definition schema schema
345createMigrations =
286createMigrations =
346 createTableIfNotExists #schema_migrations
287 createTableIfNotExists #schema_migrations
347− ( (text & notNullable) `as` #name :*
288+ ( (text & notNullable) `As` #name :*
348 (timestampWithTimeZone & notNullable & default_ currentTimestamp)
289 (timestampWithTimeZone & notNullable & default_ currentTimestamp)
349− `as` #executed_at )
290+ `As` #executed_at :* Nil )
350− ( unique #name `as` #migrations_unique_name )
291+ ( unique (#name :* Nil) `As` #migrations_unique_name :* Nil )
351−
292+
352−-- | Inserts a `Migration` into the `MigrationsTable`, returning
293+-- | Inserts a `Migration` into the `MigrationsTable`
353−-- the time at which it was inserted.
294+insertMigration
354−insertMigration :: Manipulation_ MigrationsSchemas (Only Text) ()
295+ :: Has "schema_migrations" schema ('Table MigrationsTable)
296+ => Manipulation schema '[ 'NotNull 'PGtext] '[]
355−insertMigration = insertInto_ #schema_migrations
297+insertMigration = insertRow_ #schema_migrations
298+ ( Set (param @1) `As` #name :*
356− (Values_ (Set (param @1) `as` #name :* Default `as` #executed_at))
299+ Default `As` #executed_at :* Nil )
357−
300+
358−-- | Deletes a `Migration` from the `MigrationsTable`, returning
301+-- | Deletes a `Migration` from the `MigrationsTable`
359−-- the time at which it was inserted.
360−deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()
302+deleteMigration
303+ :: Has "schema_migrations" schema ('Table MigrationsTable)
304+ => Manipulation schema '[ 'NotNull 'PGtext ] '[]
361deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)
305deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)
362
306
363-- | Selects a `Migration` from the `MigrationsTable`, returning
307-- | Selects a `Migration` from the `MigrationsTable`, returning
364−-- the time at which it was inserted.
308+-- the time at which it was executed.
365selectMigration
309selectMigration
366− :: Query_ MigrationsSchemas (Only Text) (Only UTCTime)
310+ :: Has "schema_migrations" schema ('Table MigrationsTable)
311+ => Query schema '[ 'NotNull 'PGtext ]
312+ '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]
367−selectMigration = select_ (#executed_at `as` #fromOnly)
313+selectMigration = select
314+ (#executed_at `As` #executed_at :* Nil)
368− $ from (table (#schema_migrations))
315+ ( from (table (#schema_migrations `As` #m))
369− & where_ (#name .== param @1)
316+ & where_ (#name .== param @1))
370−
371−selectMigrations :: Query_ MigrationsSchemas () MigrationRow
372−selectMigrations = select_
373− (#name `as` #migrationName :* #executed_at `as` #migrationTime)
374− (from (table #schema_migrations))
375−
376−data MigrateCommand
377− = MigrateStatus
378− | MigrateUp
379− | MigrateDown deriving (GHC.Generic, Show)
380−
381−{- | `defaultMain` creates a simple executable
382−from a connection string and a list of `Migration`s. -}
383−defaultMain
384− :: Migratory p
385− => ByteString
386− -- ^ connection string
387− -> Path (Migration p) db0 db1
388− -- ^ migrations
389− -> IO ()
390−defaultMain connectTo migrations = do
391− command <- readCommandFromArgs
392− maybe (pure ()) performCommand command
393−
394− where
395−
396− performCommand :: MigrateCommand -> IO ()
397− performCommand = \case
398− MigrateStatus -> withConnection connectTo $
399− suppressNotices >> migrateStatus
400− MigrateUp -> withConnection connectTo $
401− suppressNotices & pqThen (migrateUp migrations) & pqThen migrateStatus
402− MigrateDown -> withConnection connectTo $
403− suppressNotices & pqThen (migrateDown migrations) & pqThen migrateStatus
404−
405− migrateStatus :: PQ schema schema IO ()
406− migrateStatus = unsafePQ $ do
407− runNames <- getRunMigrationNames
408− let names = ctoList name migrations
409− unrunNames = names \\ runNames
410− liftIO $ displayRunned runNames >> displayUnrunned unrunNames
411−
412− suppressNotices :: PQ schema schema IO ()
413− suppressNotices = manipulate_ $
414− UnsafeManipulation "SET client_min_messages TO WARNING;"
415−
416− readCommandFromArgs :: IO (Maybe MigrateCommand)
417− readCommandFromArgs = getArgs >>= \case
418− ["migrate"] -> pure . Just $ MigrateUp
419− ["rollback"] -> pure . Just $ MigrateDown
420− ["status"] -> pure . Just $ MigrateStatus
421− args -> displayUsage args >> pure Nothing
422−
423− displayUsage :: [String] -> IO ()
424− displayUsage args = do
425− putStrLn $ "Invalid command: \"" <> unwords args <> "\". Use:"
426− putStrLn "migrate to run all available migrations"
427− putStrLn "rollback to rollback all available migrations"
428− putStrLn "status to display migrations run and migrations left to run"
429−
430− getRunMigrationNames :: (MonadIO m) => PQ db0 db0 m [Text]
431− getRunMigrationNames =
432− fmap migrationName <$> (unsafePQ (define createMigrations & pqThen (runQuery selectMigrations)) >>= getRows)
433−
434− displayListOfNames :: [Text] -> IO ()
435− displayListOfNames [] = Text.putStrLn " None"
436− displayListOfNames xs =
437− let singleName n = Text.putStrLn $ " - " <> n
438− in traverse_ singleName xs
439−
440− displayUnrunned :: [Text] -> IO ()
441− displayUnrunned unrunned =
442− Text.putStrLn "Migrations left to run:"
443− >> displayListOfNames unrunned
444−
445− displayRunned :: [Text] -> IO ()
446− displayRunned runned =
447− Text.putStrLn "Migrations already run:"
448− >> displayListOfNames runned
squeal-postgresql/src/Squeal/PostgreSQL/PG.hsdeleted−388
@@ -1,388 +0,0 @@
1−{-|
2−Module: Squeal.PostgreSQL.PG
3−Description: Embedding of Haskell types into Postgres's type system
4−Copyright: (c) Eitan Chatav, 2010
5−Maintainer: eitan@morphism.tech
6−Stability: experimental
7−
8−`Squeal.PostgreSQL.PG` provides type families for turning Haskell
9−`Type`s into corresponding Postgres types.
10−-}
11−{-# LANGUAGE
12− AllowAmbiguousTypes
13− , DeriveAnyClass
14− , DeriveFoldable
15− , DeriveFunctor
16− , DeriveGeneric
17− , DeriveTraversable
18− , DerivingStrategies
19− , DefaultSignatures
20− , FlexibleContexts
21− , FlexibleInstances
22− , FunctionalDependencies
23− , GADTs
24− , LambdaCase
25− , MultiParamTypeClasses
26− , OverloadedStrings
27− , ScopedTypeVariables
28− , TypeApplications
29− , TypeFamilies
30− , TypeInType
31− , TypeOperators
32− , UndecidableInstances
33− , UndecidableSuperClasses
34−#-}
35−
36−module Squeal.PostgreSQL.PG
37− ( -- * PG embeddings
38− PG
39− , NullPG
40− , TuplePG
41− , RowPG
42− -- * Storage newtypes
43− , Money (..)
44− , Json (..)
45− , Jsonb (..)
46− , Composite (..)
47− , Enumerated (..)
48− , VarArray (..)
49− , FixArray (..)
50− , LibPQ.Oid (..)
51− -- * Type families
52− , LabelsPG
53− , DimPG
54− , FixPG
55− , TupleOf
56− , TupleCodeOf
57− , RowOf
58− , ConstructorsOf
59− , ConstructorNameOf
60− , ConstructorNamesOf
61− ) where
62−
63−import Data.Aeson (Value)
64−import Data.Kind (Type)
65−import Data.Int (Int16, Int32, Int64)
66−import Data.Scientific (Scientific)
67−import Data.Time (Day, DiffTime, LocalTime, TimeOfDay, TimeZone, UTCTime)
68−import Data.Vector (Vector)
69−import Data.UUID.Types (UUID)
70−import GHC.TypeLits
71−import Network.IP.Addr (NetAddr, IP)
72−
73−import qualified Data.ByteString.Lazy as Lazy (ByteString)
74−import qualified Data.ByteString as Strict (ByteString)
75−import qualified Data.Text.Lazy as Lazy (Text)
76−import qualified Data.Text as Strict (Text)
77−import qualified Database.PostgreSQL.LibPQ as LibPQ
78−import qualified GHC.Generics as GHC
79−import qualified Generics.SOP as SOP
80−import qualified Generics.SOP.Record as SOP
81−import qualified Generics.SOP.Type.Metadata as Type
82−
83−import Squeal.PostgreSQL.Alias
84−import Squeal.PostgreSQL.Schema
85−
86−-- $setup
87−-- >>> import Squeal.PostgreSQL
88−-- >>> import Data.Text (Text)
89−
90−{- | The `PG` type family embeds a subset of Haskell types
91−as Postgres types. As an open type family, `PG` is extensible.
92−
93−>>> :kind! PG LocalTime
94−PG LocalTime :: PGType
95−= 'PGtimestamp
96−
97−>>> newtype MyDouble = My Double
98−>>> :set -XTypeFamilies
99−>>> type instance PG MyDouble = 'PGfloat8
100−-}
101−type family PG (hask :: Type) :: PGType
102−-- | `PGbool`
103−type instance PG Bool = 'PGbool
104−-- | `PGint2`
105−type instance PG Int16 = 'PGint2
106−-- | `PGint4`
107−type instance PG Int32 = 'PGint4
108−-- | `PGint8`
109−type instance PG Int64 = 'PGint8
110−-- | `PGint2`
111−type instance PG LibPQ.Oid = 'PGoid
112−-- | `PGnumeric`
113−type instance PG Scientific = 'PGnumeric
114−-- | `PGfloat4`
115−type instance PG Float = 'PGfloat4
116−-- | `PGfloat8`
117−type instance PG Double = 'PGfloat8
118−-- | `PGchar` @1@
119−type instance PG Char = 'PGchar 1
120−-- | `PGtext`
121−type instance PG Strict.Text = 'PGtext
122−-- | `PGtext`
123−type instance PG Lazy.Text = 'PGtext
124−-- | `PGtext`
125−type instance PG String = 'PGtext
126−-- | `PGbytea`
127−type instance PG Strict.ByteString = 'PGbytea
128−-- | `PGbytea`
129−type instance PG Lazy.ByteString = 'PGbytea
130−-- | `PGtimestamp`
131−type instance PG LocalTime = 'PGtimestamp
132−-- | `PGtimestamptz`
133−type instance PG UTCTime = 'PGtimestamptz
134−-- | `PGdate`
135−type instance PG Day = 'PGdate
136−-- | `PGtime`
137−type instance PG TimeOfDay = 'PGtime
138−-- | `PGtimetz`
139−type instance PG (TimeOfDay, TimeZone) = 'PGtimetz
140−-- | `PGinterval`
141−type instance PG DiffTime = 'PGinterval
142−-- | `PGuuid`
143−type instance PG UUID = 'PGuuid
144−-- | `PGinet`
145−type instance PG (NetAddr IP) = 'PGinet
146−-- | `PGjson`
147−type instance PG Value = 'PGjson
148−
149−{-| The `LabelsPG` type family calculates the constructors of a
150−Haskell enum type.
151−
152−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
153−>>> instance SOP.Generic Schwarma
154−>>> instance SOP.HasDatatypeInfo Schwarma
155−>>> :kind! LabelsPG Schwarma
156−LabelsPG Schwarma :: [Type.ConstructorName]
157−= '["Beef", "Lamb", "Chicken"]
158−-}
159−type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where
160− LabelsPG hask =
161− ConstructorNamesOf (ConstructorsOf (SOP.DatatypeInfoOf hask))
162−
163−{- |
164−`RowPG` turns a Haskell `Type` into a `RowType`.
165−
166−`RowPG` may be applied to normal Haskell record types provided they
167−have `SOP.Generic` and `SOP.HasDatatypeInfo` instances;
168−
169−>>> data Person = Person { name :: Strict.Text, age :: Int32 } deriving GHC.Generic
170−>>> instance SOP.Generic Person
171−>>> instance SOP.HasDatatypeInfo Person
172−>>> :kind! RowPG Person
173−RowPG Person :: [(Symbol, NullityType)]
174−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]
175−-}
176−type family RowPG (hask :: Type) :: RowType where
177− RowPG hask = RowOf (SOP.RecordCodeOf hask)
178−
179−-- | `RowOf` applies `NullPG` to the fields of a list.
180−type family RowOf (record :: [(Symbol, Type)]) :: RowType where
181− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': col4 ::: ty4 ': record) =
182− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': col4 ::: NullPG ty4 ': RowOf record
183− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': record) =
184− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': RowOf record
185− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': record) =
186− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': RowOf record
187− RowOf (col ::: ty ': col1 ::: ty1 ': record) =
188− col ::: NullPG ty ': col1::: NullPG ty1 ': RowOf record
189− RowOf (col ::: ty ': record) = col ::: NullPG ty ': RowOf record
190− RowOf '[] = '[]
191−
192−{- | `NullPG` turns a Haskell type into a `NullityType`.
193−
194−>>> :kind! NullPG Double
195−NullPG Double :: NullityType
196−= 'NotNull 'PGfloat8
197−>>> :kind! NullPG (Maybe Double)
198−NullPG (Maybe Double) :: NullityType
199−= 'Null 'PGfloat8
200−-}
201−type family NullPG (hask :: Type) :: NullityType where
202− NullPG (Maybe hask) = 'Null (PG hask)
203− NullPG hask = 'NotNull (PG hask)
204−
205−{- | `TuplePG` turns a Haskell tuple type (including record types) into
206−the corresponding list of `NullityType`s.
207−
208−>>> :kind! TuplePG (Double, Maybe Char)
209−TuplePG (Double, Maybe Char) :: [NullityType]
210−= '[ 'NotNull 'PGfloat8, 'Null ('PGchar 1)]
211−-}
212−type family TuplePG (hask :: Type) :: [NullityType] where
213− TuplePG hask = TupleOf (TupleCodeOf hask (SOP.Code hask))
214−
215−-- | `TupleOf` turns a list of Haskell `Type`s into a list of `NullityType`s.
216−type family TupleOf (tuple :: [Type]) :: [NullityType] where
217− TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': hask5 ': tuple) =
218− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': NullPG hask5 ': TupleOf tuple
219− TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': tuple) =
220− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': TupleOf tuple
221− TupleOf (hask ': hask1 ': hask2 ': hask3 ': tuple) =
222− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': TupleOf tuple
223− TupleOf (hask ': hask1 ': hask2 ': tuple) =
224− NullPG hask ': NullPG hask1 ': NullPG hask2 ': TupleOf tuple
225− TupleOf (hask ': hask1 ': tuple) = NullPG hask ': NullPG hask1 ': TupleOf tuple
226− TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple
227− TupleOf '[] = '[]
228−
229−-- | `TupleCodeOf` takes the `SOP.Code` of a haskell `Type`
230−-- and if it's a simple product returns it, otherwise giving a `TypeError`.
231−type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where
232− TupleCodeOf hask '[tuple] = tuple
233− TupleCodeOf hask '[] =
234− TypeError
235− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."
236− ':$$: 'Text "It is a void type with no constructors."
237− )
238− TupleCodeOf hask (_ ': _ ': _) =
239− TypeError
240− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."
241− ':$$: 'Text "It is a sum type with more than one constructor."
242− )
243−
244−-- | Calculates constructors of a datatype.
245−type family ConstructorsOf (datatype :: Type.DatatypeInfo)
246− :: [Type.ConstructorInfo] where
247− ConstructorsOf ('Type.ADT _module _datatype constructors) =
248− constructors
249− ConstructorsOf ('Type.Newtype _module _datatype constructor) =
250− '[constructor]
251−
252−-- | Calculates the name of a nullary constructor, otherwise
253−-- generates a type error.
254−type family ConstructorNameOf (constructor :: Type.ConstructorInfo)
255− :: Type.ConstructorName where
256− ConstructorNameOf ('Type.Constructor name) = name
257− ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError
258− ('Text "ConstructorNameOf error: non-nullary constructor "
259− ':<>: 'Text name)
260− ConstructorNameOf ('Type.Record name _fields) = TypeError
261− ('Text "ConstructorNameOf error: non-nullary constructor "
262− ':<>: 'Text name)
263−
264−-- | Calculate the names of nullary constructors.
265−type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])
266− :: [Type.ConstructorName] where
267− ConstructorNamesOf '[] = '[]
268− ConstructorNamesOf (constructor ': constructors) =
269− ConstructorNameOf constructor ': ConstructorNamesOf constructors
270−
271−-- | `DimPG` turns Haskell nested homogeneous tuples into a list of lengths.
272−type family DimPG (hask :: Type) :: [Nat] where
273− DimPG (x,x) = 2 ': DimPG x
274− DimPG (x,x,x) = 3 ': DimPG x
275− DimPG (x,x,x,x) = 4 ': DimPG x
276− DimPG (x,x,x,x,x) = 5 ': DimPG x
277− DimPG (x,x,x,x,x,x) = 6 ': DimPG x
278− DimPG (x,x,x,x,x,x,x) = 7 ': DimPG x
279− DimPG (x,x,x,x,x,x,x,x) = 8 ': DimPG x
280− DimPG (x,x,x,x,x,x,x,x,x) = 9 ': DimPG x
281− DimPG (x,x,x,x,x,x,x,x,x,x) = 10 ': DimPG x
282− DimPG x = '[]
283−
284−-- | `FixPG` extracts `NullPG` of the base type of nested homogeneous tuples.
285−type family FixPG (hask :: Type) :: NullityType where
286− FixPG (x,x) = FixPG x
287− FixPG (x,x,x) = FixPG x
288− FixPG (x,x,x,x) = FixPG x
289− FixPG (x,x,x,x,x) = FixPG x
290− FixPG (x,x,x,x,x,x) = FixPG x
291− FixPG (x,x,x,x,x,x,x) = FixPG x
292− FixPG (x,x,x,x,x,x,x,x) = FixPG x
293− FixPG (x,x,x,x,x,x,x,x,x) = FixPG x
294− FixPG (x,x,x,x,x,x,x,x,x,x) = FixPG x
295− FixPG (x,x,x,x,x,x,x,x,x,x,x) = FixPG x
296− FixPG x = NullPG x
297−
298−{- | The `Money` newtype stores a monetary value in terms
299−of the number of cents, i.e. @$2,000.20@ would be expressed as
300−@Money { cents = 200020 }@.
301−
302−>>> import Control.Monad (void)
303−>>> import Control.Monad.IO.Class (liftIO)
304−>>> import Squeal.PostgreSQL
305−>>> :{
306−let
307− roundTrip :: Query_ (Public '[]) (Only Money) (Only Money)
308− roundTrip = values_ $ parameter @1 money `as` #fromOnly
309−:}
310−
311−>>> let input = Only (Money 20020)
312−
313−>>> :{
314−withConnection "host=localhost port=5432 dbname=exampledb" $ do
315− result <- runQueryParams roundTrip input
316− Just output <- firstRow result
317− liftIO . print $ input == output
318−:}
319−True
320−-}
321−newtype Money = Money { cents :: Int64 }
322− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
323− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
324−-- | `PGmoney`
325−type instance PG Money = 'PGmoney
326−
327−{- | The `Json` newtype is an indication that the Haskell
328−type it's applied to should be stored as a `PGjson`.
329−-}
330−newtype Json hask = Json {getJson :: hask}
331− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
332− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
333−-- | `PGjson`
334−type instance PG (Json hask) = 'PGjson
335−
336−{- | The `Jsonb` newtype is an indication that the Haskell
337−type it's applied to should be stored as a `PGjsonb`.
338−-}
339−newtype Jsonb hask = Jsonb {getJsonb :: hask}
340− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
341− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
342−-- | `PGjsonb`
343−type instance PG (Jsonb hask) = 'PGjsonb
344−
345−{- | The `Composite` newtype is an indication that the Haskell
346−type it's applied to should be stored as a `PGcomposite`.
347−-}
348−newtype Composite record = Composite {getComposite :: record}
349− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
350− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
351−-- | `PGcomposite` @(@`RowPG` @hask)@
352−type instance PG (Composite hask) = 'PGcomposite (RowPG hask)
353−
354−{- | The `Enumerated` newtype is an indication that the Haskell
355−type it's applied to should be stored as a `PGenum`.
356−-}
357−newtype Enumerated enum = Enumerated {getEnumerated :: enum}
358− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
359− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
360−-- | `PGenum` @(@`LabelsPG` @hask)@
361−type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)
362−
363−{- | The `VarArray` newtype is an indication that the Haskell
364−type it's applied to should be stored as a `PGvararray`.
365−
366−>>> :kind! PG (VarArray (Vector Double))
367−PG (VarArray (Vector Double)) :: PGType
368−= 'PGvararray ('NotNull 'PGfloat8)
369−-}
370−newtype VarArray arr = VarArray {getVarArray :: arr}
371− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
372− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
373−-- | `PGvararray` @(@`NullPG` @hask)@
374−type instance PG (VarArray (Vector hask)) = 'PGvararray (NullPG hask)
375−type instance PG (VarArray [hask]) = 'PGvararray (NullPG hask)
376−
377−{- | The `FixArray` newtype is an indication that the Haskell
378−type it's applied to should be stored as a `PGfixarray`.
379−
380−>>> :kind! PG (FixArray ((Double, Double), (Double, Double)))
381−PG (FixArray ((Double, Double), (Double, Double))) :: PGType
382−= 'PGfixarray '[2, 2] ('NotNull 'PGfloat8)
383−-}
384−newtype FixArray arr = FixArray {getFixArray :: arr}
385− deriving stock (Eq, Ord, Show, Read, GHC.Generic)
386− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
387−-- | `PGfixarray` @(@`DimPG` @hask) (@`FixPG` @hask)@
388−type instance PG (FixArray hask) = 'PGfixarray (DimPG hask) (FixPG hask)
squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+211−312
@@ -6,12 +6,12 @@ Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
8This module is where Squeal commands actually get executed by
8This module is where Squeal commands actually get executed by
9−`Database.PostgreSQL.LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing
9+`LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing
10a `Definition` and `MonadPQ` for executing a `Manipulation` or `Query`,
10a `Definition` and `MonadPQ` for executing a `Manipulation` or `Query`,
11and a `PQ` type with instances for them.
11and a `PQ` type with instances for them.
12
12
13Using Squeal in your application will come down to defining
13Using Squeal in your application will come down to defining
14−the @schemas@ of your database and including @PQ schemas schemas@ in your
14+the @schema@ of your database and including @PQ schema schema@ in your
15application's monad transformer stack, giving it an instance of `MonadPQ`.
15application's monad transformer stack, giving it an instance of `MonadPQ`.
16
16
17This module also provides functions for retrieving rows from the `LibPQ.Result`
17This module also provides functions for retrieving rows from the `LibPQ.Result`
@@ -24,7 +24,6 @@ of executing Squeal commands.
24 , FunctionalDependencies
24 , FunctionalDependencies
25 , FlexibleContexts
25 , FlexibleContexts
26 , FlexibleInstances
26 , FlexibleInstances
27− , InstanceSigs
28 , OverloadedStrings
27 , OverloadedStrings
29 , RankNTypes
28 , RankNTypes
30 , ScopedTypeVariables
29 , ScopedTypeVariables
@@ -49,7 +48,9 @@ module Squeal.PostgreSQL.PQ
49 , evalPQ
48 , evalPQ
50 , IndexedMonadTransPQ (..)
49 , IndexedMonadTransPQ (..)
51 , MonadPQ (..)
50 , MonadPQ (..)
52− -- * Results
51+ , PQRun
52+ , pqliftWith
53+ -- * Result
53 , LibPQ.Result
54 , LibPQ.Result
54 , LibPQ.Row
55 , LibPQ.Row
55 , ntuples
56 , ntuples
@@ -61,33 +62,22 @@ module Squeal.PostgreSQL.PQ
61 , LibPQ.ExecStatus (..)
62 , LibPQ.ExecStatus (..)
62 , resultStatus
63 , resultStatus
63 , resultErrorMessage
64 , resultErrorMessage
64− , resultErrorCode
65− -- * Exceptions
66− , SquealException (..)
67− , PQState (..)
68− , okResult
69− , catchSqueal
70− , handleSqueal
71− , trySqueal
72 ) where
65 ) where
73
66
74−import Control.Exception (Exception, throw)
67+import Control.Exception.Lifted
68+import Control.Monad.Base
75import Control.Monad.Except
69import Control.Monad.Except
76import Control.Monad.Morph
70import Control.Monad.Morph
77−import UnliftIO (MonadUnliftIO (..), bracket, catch, handle, try)
71+import Control.Monad.Trans.Control
78import Data.ByteString (ByteString)
72import Data.ByteString (ByteString)
79import Data.Foldable
73import Data.Foldable
80import Data.Function ((&))
74import Data.Function ((&))
81−import Data.Functor ((<&>))
82import Data.Kind
75import Data.Kind
83−import Data.Text (pack, Text)
76+import Data.Monoid
84import Data.Traversable
77import Data.Traversable
85import Generics.SOP
78import Generics.SOP
86−import PostgreSQL.Binary.Encoding (encodingBytes)
87
79
88−import qualified Control.Monad.Fail as Fail
89import qualified Database.PostgreSQL.LibPQ as LibPQ
80import qualified Database.PostgreSQL.LibPQ as LibPQ
90−import qualified PostgreSQL.Binary.Encoding as Encoding
91
81
92import Squeal.PostgreSQL.Binary
82import Squeal.PostgreSQL.Binary
93import Squeal.PostgreSQL.Definition
83import Squeal.PostgreSQL.Definition
@@ -100,6 +90,7 @@ import Control.Monad.Trans.Identity
100import Control.Monad.Trans.Reader
90import Control.Monad.Trans.Reader
101import Control.Monad.Trans.Maybe
91import Control.Monad.Trans.Maybe
102import Control.Monad.Trans.Cont
92import Control.Monad.Trans.Cont
93+import Control.Monad.Trans.List
103
94
104import qualified Control.Monad.Trans.State.Lazy as Lazy
95import qualified Control.Monad.Trans.State.Lazy as Lazy
105import qualified Control.Monad.Trans.State.Strict as Strict
96import qualified Control.Monad.Trans.State.Strict as Strict
@@ -108,9 +99,6 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict
108import qualified Control.Monad.Trans.RWS.Lazy as Lazy
99import qualified Control.Monad.Trans.RWS.Lazy as Lazy
109import qualified Control.Monad.Trans.RWS.Strict as Strict
100import qualified Control.Monad.Trans.RWS.Strict as Strict
110
101
111−-- $setup
112−-- >>> import Squeal.PostgreSQL
113−
114{- | Makes a new connection to the database server.
102{- | Makes a new connection to the database server.
115
103
116This function opens a new database connection using the parameters taken
104This function opens a new database connection using the parameters taken
@@ -137,22 +125,22 @@ Note that, for now, squeal doesn't offer any protection from connecting
137with the wrong schema!
125with the wrong schema!
138-}
126-}
139connectdb
127connectdb
140− :: forall schemas io
128+ :: forall schema io
141− . MonadIO io
129+ . MonadBase IO io
142 => ByteString -- ^ conninfo
130 => ByteString -- ^ conninfo
143− -> io (K LibPQ.Connection schemas)
131+ -> io (K LibPQ.Connection schema)
144−connectdb = fmap K . liftIO . LibPQ.connectdb
132+connectdb = fmap K . liftBase . LibPQ.connectdb
145
133
146-- | Closes the connection to the server.
134-- | Closes the connection to the server.
147−finish :: MonadIO io => K LibPQ.Connection schemas -> io ()
135+finish :: MonadBase IO io => K LibPQ.Connection schema -> io ()
148−finish = liftIO . LibPQ.finish . unK
136+finish = liftBase . LibPQ.finish . unK
149
137
150-- | Do `connectdb` and `finish` before and after a computation.
138-- | Do `connectdb` and `finish` before and after a computation.
151withConnection
139withConnection
152− :: forall schemas0 schemas1 io x
140+ :: forall schema0 schema1 io x
153− . MonadUnliftIO io
141+ . MonadBaseControl IO io
154 => ByteString
142 => ByteString
155− -> PQ schemas0 schemas1 io x
143+ -> PQ schema0 schema1 io x
156 -> io x
144 -> io x
157withConnection connString action = do
145withConnection connString action = do
158 K x <- bracket (connectdb connString) finish (unPQ action)
146 K x <- bracket (connectdb connString) finish (unPQ action)
@@ -160,47 +148,47 @@ withConnection connString action = do
160
148
161-- | Safely `lowerConnection` to a smaller schema.
149-- | Safely `lowerConnection` to a smaller schema.
162lowerConnection
150lowerConnection
163− :: K LibPQ.Connection (schema ': schemas)
151+ :: K LibPQ.Connection (table ': schema)
164− -> K LibPQ.Connection schemas
152+ -> K LibPQ.Connection schema
165lowerConnection (K conn) = K conn
153lowerConnection (K conn) = K conn
166
154
167-- | We keep track of the schema via an Atkey indexed state monad transformer,
155-- | We keep track of the schema via an Atkey indexed state monad transformer,
168-- `PQ`.
156-- `PQ`.
169newtype PQ
157newtype PQ
170− (schemas0 :: SchemasType)
158+ (schema0 :: SchemaType)
171− (schemas1 :: SchemasType)
159+ (schema1 :: SchemaType)
172 (m :: Type -> Type)
160 (m :: Type -> Type)
173 (x :: Type) =
161 (x :: Type) =
174− PQ { unPQ :: K LibPQ.Connection schemas0 -> m (K x schemas1) }
162+ PQ { unPQ :: K LibPQ.Connection schema0 -> m (K x schema1) }
175
163
176−instance Monad m => Functor (PQ schemas0 schemas1 m) where
164+instance Monad m => Functor (PQ schema0 schema1 m) where
177 fmap f (PQ pq) = PQ $ \ conn -> do
165 fmap f (PQ pq) = PQ $ \ conn -> do
178 K x <- pq conn
166 K x <- pq conn
179 return $ K (f x)
167 return $ K (f x)
180
168
181−-- | Run a `PQ` and keep the result and the `LibPQ.Connection`.
169+-- | Run a `PQ` and keep the result and the `Connection`.
182runPQ
170runPQ
183 :: Functor m
171 :: Functor m
184− => PQ schemas0 schemas1 m x
172+ => PQ schema0 schema1 m x
185− -> K LibPQ.Connection schemas0
173+ -> K LibPQ.Connection schema0
186− -> m (x, K LibPQ.Connection schemas1)
174+ -> m (x, K LibPQ.Connection schema1)
187runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn
175runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn
188 -- K x <- pq conn
176 -- K x <- pq conn
189 -- return (x, K (unK conn))
177 -- return (x, K (unK conn))
190
178
191−-- | Execute a `PQ` and discard the result but keep the `LibPQ.Connection`.
179+-- | Execute a `PQ` and discard the result but keep the `Connection`.
192execPQ
180execPQ
193 :: Functor m
181 :: Functor m
194− => PQ schemas0 schemas1 m x
182+ => PQ schema0 schema1 m x
195− -> K LibPQ.Connection schemas0
183+ -> K LibPQ.Connection schema0
196− -> m (K LibPQ.Connection schemas1)
184+ -> m (K LibPQ.Connection schema1)
197execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn
185execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn
198
186
199−-- | Evaluate a `PQ` and discard the `LibPQ.Connection` but keep the result.
187+-- | Evaluate a `PQ` and discard the `Connection` but keep the result.
200evalPQ
188evalPQ
201 :: Functor m
189 :: Functor m
202− => PQ schemas0 schemas1 m x
190+ => PQ schema0 schema1 m x
203− -> K LibPQ.Connection schemas0
191+ -> K LibPQ.Connection schema0
204 -> m x
192 -> m x
205evalPQ (PQ pq) conn = unK <$> pq conn
193evalPQ (PQ pq) conn = unK <$> pq conn
206
194
@@ -208,56 +196,60 @@ evalPQ (PQ pq) conn = unK <$> pq conn
208-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).
196-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).
209-- An indexed monad transformer transforms a `Monad` into an indexed monad.
197-- An indexed monad transformer transforms a `Monad` into an indexed monad.
210-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that
198-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that
211−-- support running `Definition`s using `define`.
199+-- support running `Definition`s using `define` and embedding a computation
200+-- in a larger schema using `pqEmbed`.
212class IndexedMonadTransPQ pq where
201class IndexedMonadTransPQ pq where
213
202
214 -- | indexed analog of `<*>`
203 -- | indexed analog of `<*>`
215 pqAp
204 pqAp
216 :: Monad m
205 :: Monad m
217− => pq schemas0 schemas1 m (x -> y)
206+ => pq schema0 schema1 m (x -> y)
218− -> pq schemas1 schemas2 m x
207+ -> pq schema1 schema2 m x
219− -> pq schemas0 schemas2 m y
208+ -> pq schema0 schema2 m y
220
209
221 -- | indexed analog of `join`
210 -- | indexed analog of `join`
222 pqJoin
211 pqJoin
223 :: Monad m
212 :: Monad m
224− => pq schemas0 schemas1 m (pq schemas1 schemas2 m y)
213+ => pq schema0 schema1 m (pq schema1 schema2 m y)
225− -> pq schemas0 schemas2 m y
214+ -> pq schema0 schema2 m y
226 pqJoin pq = pq & pqBind id
215 pqJoin pq = pq & pqBind id
227
216
228 -- | indexed analog of `=<<`
217 -- | indexed analog of `=<<`
229 pqBind
218 pqBind
230 :: Monad m
219 :: Monad m
231− => (x -> pq schemas1 schemas2 m y)
220+ => (x -> pq schema1 schema2 m y)
232− -> pq schemas0 schemas1 m x
221+ -> pq schema0 schema1 m x
233− -> pq schemas0 schemas2 m y
222+ -> pq schema0 schema2 m y
234
223
235 -- | indexed analog of flipped `>>`
224 -- | indexed analog of flipped `>>`
236 pqThen
225 pqThen
237 :: Monad m
226 :: Monad m
238− => pq schemas1 schemas2 m y
227+ => pq schema1 schema2 m y
239− -> pq schemas0 schemas1 m x
228+ -> pq schema0 schema1 m x
240− -> pq schemas0 schemas2 m y
229+ -> pq schema0 schema2 m y
241 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)
230 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)
242
231
243 -- | indexed analog of `<=<`
232 -- | indexed analog of `<=<`
244 pqAndThen
233 pqAndThen
245 :: Monad m
234 :: Monad m
246− => (y -> pq schemas1 schemas2 m z)
235+ => (y -> pq schema1 schema2 m z)
247− -> (x -> pq schemas0 schemas1 m y)
236+ -> (x -> pq schema0 schema1 m y)
248− -> x -> pq schemas0 schemas2 m z
237+ -> x -> pq schema0 schema2 m z
249 pqAndThen g f x = pqBind g (f x)
238 pqAndThen g f x = pqBind g (f x)
250
239
240+ -- | Safely embed a computation in a larger schema.
241+ pqEmbed
242+ :: Monad m
243+ => pq schema0 schema1 m x
244+ -> pq (table ': schema0) (table : schema1) m x
245+
251− -- | Run a `Definition` with `LibPQ.exec`.
246+ -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law
252− --
253− -- It should be functorial in effect.
254 --
247 --
255− -- @define id = return ()@
256− -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@
248+ -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@
257 define
249 define
258− :: MonadIO io
250+ :: MonadBase IO io
259− => Definition schemas0 schemas1
251+ => Definition schema0 schema1
260− -> pq schemas0 schemas1 io ()
252+ -> pq schema0 schema1 io (K LibPQ.Result '[])
261
253
262instance IndexedMonadTransPQ PQ where
254instance IndexedMonadTransPQ PQ where
263
255
@@ -270,26 +262,26 @@ instance IndexedMonadTransPQ PQ where
270 K x' <- x conn
262 K x' <- x conn
271 unPQ (f x') (K (unK conn))
263 unPQ (f x') (K (unK conn))
272
264
265+ pqEmbed (PQ pq) = PQ $ \ (K conn) -> do
266+ K x <- pq (K conn)
267+ return $ K x
268+
273 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do
269 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do
274− resultMaybe <- liftIO $ LibPQ.exec conn q
270+ resultMaybe <- liftBase $ LibPQ.exec conn q
275 case resultMaybe of
271 case resultMaybe of
276− Nothing -> throw $ ResultException
272+ Nothing -> error
277 "define: LibPQ.exec returned no results"
273 "define: LibPQ.exec returned no results"
278− Just result -> K <$> okResult_ result
274+ Just result -> return $ K (K result)
279
275
280−{- | `MonadPQ` is an @mtl@ style constraint, similar to
276+{- | `MonadPQ` is an `mtl` style constraint, similar to
281−`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to
277+`Control.Monad.State.Class.MonadState`, for using `LibPQ` to
282
278
283* `manipulateParams` runs a `Manipulation` with params from a type
279* `manipulateParams` runs a `Manipulation` with params from a type
284 with a `ToParams` constraint. It calls `LibPQ.execParams` and
280 with a `ToParams` constraint. It calls `LibPQ.execParams` and
285 doesn't afraid of anything.
281 doesn't afraid of anything.
286
282
287−* `manipulateParams_` is like `manipulateParams` for a returning-free statement.
288−
289* `manipulate` is like `manipulateParams` for a parameter-free statement.
283* `manipulate` is like `manipulateParams` for a parameter-free statement.
290
284
291−* `manipulate_` is like `manipulate` for a returning-free statement.
292−
293* `runQueryParams` is like `manipulateParams` for query statements.
285* `runQueryParams` is like `manipulateParams` for query statements.
294
286
295* `runQuery` is like `runQueryParams` for a parameter-free statement.
287* `runQuery` is like `runQueryParams` for a parameter-free statement.
@@ -303,11 +295,11 @@ instance IndexedMonadTransPQ PQ where
303* `forPrepared` is a flipped `traversePrepared`
295* `forPrepared` is a flipped `traversePrepared`
304
296
305* `traversePrepared_` is like `traversePrepared` but works on `Foldable`
297* `traversePrepared_` is like `traversePrepared` but works on `Foldable`
306− containers for a returning-free statement.
298+ containers and returns unit.
307
299
308* `forPrepared_` is a flipped `traversePrepared_`.
300* `forPrepared_` is a flipped `traversePrepared_`.
309
301
310−* `liftPQ` lets you lift actions from `Database.PostgreSQL.LibPQ` that require a connection
302+* `liftPQ` lets you lift actions from `LibPQ` that require a connection
311 into your monad.
303 into your monad.
312
304
313To define an instance, you can minimally define only `manipulateParams`,
305To define an instance, you can minimally define only `manipulateParams`,
@@ -315,398 +307,305 @@ To define an instance, you can minimally define only `manipulateParams`,
315a default instance.
307a default instance.
316
308
317-}
309-}
318−class Monad pq => MonadPQ schemas pq | pq -> schemas where
310+class Monad pq => MonadPQ schema pq | pq -> schema where
319 manipulateParams
311 manipulateParams
320− :: (ToParams x params, All OidOfParam params)
312+ :: ToParams x params
321− => Manipulation '[] schemas params ys
313+ => Manipulation schema params ys
322− -- ^ `insertInto`, `update` or `deleteFrom`
314+ -- ^ `insertRows`, `update` or `deleteFrom`
323 -> x -> pq (K LibPQ.Result ys)
315 -> x -> pq (K LibPQ.Result ys)
324 default manipulateParams
316 default manipulateParams
325− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
317+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
326− => (ToParams x params, All OidOfParam params)
318+ => ToParams x params
327− => Manipulation '[] schemas params ys
319+ => Manipulation schema params ys
328− -- ^ `insertInto`, `update` or `deleteFrom`
320+ -- ^ `insertRows`, `update` or `deleteFrom`
329 -> x -> pq (K LibPQ.Result ys)
321 -> x -> pq (K LibPQ.Result ys)
330 manipulateParams manipulation params = lift $
322 manipulateParams manipulation params = lift $
331 manipulateParams manipulation params
323 manipulateParams manipulation params
332
324
333− manipulateParams_
334− :: (ToParams x params, All OidOfParam params)
335− => Manipulation '[] schemas params '[]
336− -- ^ `insertInto`, `update` or `deleteFrom`
337− -> x -> pq ()
338− manipulateParams_ q x = void $ manipulateParams q x
339−
340− manipulate :: Manipulation '[] schemas '[] ys -> pq (K LibPQ.Result ys)
325+ manipulate :: Manipulation schema '[] ys -> pq (K LibPQ.Result ys)
341 manipulate statement = manipulateParams statement ()
326 manipulate statement = manipulateParams statement ()
342
327
343− manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()
344− manipulate_ = void . manipulate
345−
346 runQueryParams
328 runQueryParams
347− :: (ToParams x params, All OidOfParam params)
329+ :: ToParams x params
348− => Query '[] '[] schemas params ys
330+ => Query schema params ys
349 -- ^ `select` and friends
331 -- ^ `select` and friends
350 -> x -> pq (K LibPQ.Result ys)
332 -> x -> pq (K LibPQ.Result ys)
351 runQueryParams = manipulateParams . queryStatement
333 runQueryParams = manipulateParams . queryStatement
352
334
353 runQuery
335 runQuery
354− :: Query '[] '[] schemas '[] ys
336+ :: Query schema '[] ys
355 -- ^ `select` and friends
337 -- ^ `select` and friends
356 -> pq (K LibPQ.Result ys)
338 -> pq (K LibPQ.Result ys)
357 runQuery q = runQueryParams q ()
339 runQuery q = runQueryParams q ()
358
340
359 traversePrepared
341 traversePrepared
360− :: (ToParams x params, Traversable list, All OidOfParam params)
342+ :: (ToParams x params, Traversable list)
361− => Manipulation '[] schemas params ys
343+ => Manipulation schema params ys
362− -- ^ `insertInto`, `update`, or `deleteFrom`, and friends
344+ -- ^ `insertRows`, `update`, or `deleteFrom`, and friends
363 -> list x -> pq (list (K LibPQ.Result ys))
345 -> list x -> pq (list (K LibPQ.Result ys))
364 default traversePrepared
346 default traversePrepared
365− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
347+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
366− => (ToParams x params, Traversable list, All OidOfParam params)
348+ => (ToParams x params, Traversable list)
367− => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))
349+ => Manipulation schema params ys -> list x -> pq (list (K LibPQ.Result ys))
368 traversePrepared manipulation params = lift $
350 traversePrepared manipulation params = lift $
369 traversePrepared manipulation params
351 traversePrepared manipulation params
370
352
371 forPrepared
353 forPrepared
372− :: (ToParams x params, Traversable list, All OidOfParam params)
354+ :: (ToParams x params, Traversable list)
373 => list x
355 => list x
374− -> Manipulation '[] schemas params ys
356+ -> Manipulation schema params ys
375− -- ^ `insertInto`, `update` or `deleteFrom`
357+ -- ^ `insertRows`, `update` or `deleteFrom`
376 -> pq (list (K LibPQ.Result ys))
358 -> pq (list (K LibPQ.Result ys))
377 forPrepared = flip traversePrepared
359 forPrepared = flip traversePrepared
378
360
379 traversePrepared_
361 traversePrepared_
380− :: (ToParams x params, Foldable list, All OidOfParam params)
362+ :: (ToParams x params, Foldable list)
381− => Manipulation '[] schemas params '[]
363+ => Manipulation schema params '[]
382− -- ^ `insertInto`, `update` or `deleteFrom`
364+ -- ^ `insertRows`, `update` or `deleteFrom`
383 -> list x -> pq ()
365 -> list x -> pq ()
384 default traversePrepared_
366 default traversePrepared_
385− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
367+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
386− => (ToParams x params, Foldable list, All OidOfParam params)
368+ => (ToParams x params, Foldable list)
387− => Manipulation '[] schemas params '[]
369+ => Manipulation schema params '[]
388− -- ^ `insertInto`, `update` or `deleteFrom`
370+ -- ^ `insertRows`, `update` or `deleteFrom`
389 -> list x -> pq ()
371 -> list x -> pq ()
390 traversePrepared_ manipulation params = lift $
372 traversePrepared_ manipulation params = lift $
391 traversePrepared_ manipulation params
373 traversePrepared_ manipulation params
392
374
393 forPrepared_
375 forPrepared_
394− :: (ToParams x params, Foldable list, All OidOfParam params)
376+ :: (ToParams x params, Foldable list)
395 => list x
377 => list x
396− -> Manipulation '[] schemas params '[]
378+ -> Manipulation schema params '[]
397− -- ^ `insertInto`, `update` or `deleteFrom`
379+ -- ^ `insertRows`, `update` or `deleteFrom`
398 -> pq ()
380 -> pq ()
399 forPrepared_ = flip traversePrepared_
381 forPrepared_ = flip traversePrepared_
400
382
401 liftPQ :: (LibPQ.Connection -> IO a) -> pq a
383 liftPQ :: (LibPQ.Connection -> IO a) -> pq a
402 default liftPQ
384 default liftPQ
403− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
385+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
404 => (LibPQ.Connection -> IO a) -> pq a
386 => (LibPQ.Connection -> IO a) -> pq a
405 liftPQ = lift . liftPQ
387 liftPQ = lift . liftPQ
406
388
407−instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)
389+instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)
408− => MonadPQ schemas (PQ schemas0 schemas1 io) where
390+ => MonadPQ schema (PQ schema0 schema1 io) where
409
391
410 manipulateParams
392 manipulateParams
411− (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =
393+ (UnsafeManipulation q :: Manipulation schema ps ys) (params :: x) =
412 PQ $ \ (K conn) -> do
394 PQ $ \ (K conn) -> do
413 let
395 let
414− paramSet
396+ toParam' bytes = (LibPQ.invalidOid,bytes,LibPQ.Binary)
415− :: forall param. OidOfParam param
416− => K (Maybe Encoding.Encoding) param
417− -> K (Maybe (LibPQ.Oid, ByteString, LibPQ.Format)) param
418− paramSet (K maybeEncoding) = K $
419− maybeEncoding <&> \encoding ->
420− (oidOfParam @param, encodingBytes encoding, LibPQ.Binary)
421− params'
422− = hcollapse
423− . hcmap (Proxy @OidOfParam) paramSet
424− $ toParams @x @ps params
397+ params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))
425 q' = q <> ";"
398 q' = q <> ";"
426− resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary
399+ resultMaybe <- liftBase $ LibPQ.execParams conn q' params' LibPQ.Binary
427 case resultMaybe of
400 case resultMaybe of
428− Nothing -> throw $ ResultException
401+ Nothing -> error
429 "manipulateParams: LibPQ.execParams returned no results"
402 "manipulateParams: LibPQ.execParams returned no results"
430− Just result -> do
431− okResult_ result
432− return $ K (K result)
403+ Just result -> return $ K (K result)
433
404
434 traversePrepared
405 traversePrepared
435− (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =
406+ (UnsafeManipulation q :: Manipulation schema xs ys) (list :: list x) =
436− PQ $ \ (K conn) -> liftIO $ do
407+ PQ $ \ (K conn) -> liftBase $ do
437− let
438− temp = "temporary_statement"
408+ let temp = "temporary_statement"
439− paramOid :: forall p. OidOfParam p => K LibPQ.Oid p
440− paramOid = K (oidOfParam @p)
441− paramOids :: NP (K LibPQ.Oid) xs
442− paramOids = hcpure (Proxy @OidOfParam) paramOid
443− paramOids' :: [LibPQ.Oid]
444− paramOids' = hcollapse paramOids
445− prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')
409+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing
446 case prepResultMaybe of
410 case prepResultMaybe of
447− Nothing -> throw $ ResultException
411+ Nothing -> error
448 "traversePrepared: LibPQ.prepare returned no results"
412 "traversePrepared: LibPQ.prepare returned no results"
449− Just prepResult -> okResult_ prepResult
413+ Just prepResult -> do
414+ status <- LibPQ.resultStatus prepResult
415+ unless (status == LibPQ.CommandOk) . error $
416+ "traversePrepared: LibPQ.prepare status " <> show status
450 results <- for list $ \ params -> do
417 results <- for list $ \ params -> do
451 let
418 let
452− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
419+ toParam' bytes = (bytes,LibPQ.Binary)
453 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
420 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
454 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
421 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
455 case resultMaybe of
422 case resultMaybe of
456− Nothing -> throw $ ResultException
423+ Nothing -> error
457 "traversePrepared: LibPQ.execParams returned no results"
424 "traversePrepared: LibPQ.execParams returned no results"
458− Just result -> do
459− okResult_ result
460− return $ K result
425+ Just result -> return $ K result
461 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
426 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
462 case deallocResultMaybe of
427 case deallocResultMaybe of
463− Nothing -> throw $ ResultException
428+ Nothing -> error
464 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
429 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
465− Just deallocResult -> okResult_ deallocResult
430+ Just deallocResult -> do
431+ status <- LibPQ.resultStatus deallocResult
432+ unless (status == LibPQ.CommandOk) . error $
433+ "traversePrepared: DEALLOCATE status " <> show status
466 return (K results)
434 return (K results)
467
435
468 traversePrepared_
436 traversePrepared_
469− (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =
437+ (UnsafeManipulation q :: Manipulation schema xs '[]) (list :: list x) =
470− PQ $ \ (K conn) -> liftIO $ do
438+ PQ $ \ (K conn) -> liftBase $ do
471− let
472− temp = "temporary_statement"
439+ let temp = "temporary_statement"
473− paramOid :: forall p. OidOfParam p => K LibPQ.Oid p
474− paramOid = K (oidOfParam @p)
475− paramOids :: NP (K LibPQ.Oid) xs
476− paramOids = hcpure (Proxy @OidOfParam) paramOid
477− paramOids' :: [LibPQ.Oid]
478− paramOids' = hcollapse paramOids
479− prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')
440+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing
480 case prepResultMaybe of
441 case prepResultMaybe of
481− Nothing -> throw $ ResultException
442+ Nothing -> error
482 "traversePrepared_: LibPQ.prepare returned no results"
443 "traversePrepared_: LibPQ.prepare returned no results"
483− Just prepResult -> okResult_ prepResult
444+ Just prepResult -> do
445+ status <- LibPQ.resultStatus prepResult
446+ unless (status == LibPQ.CommandOk) . error $
447+ "traversePrepared: LibPQ.prepare status " <> show status
484 for_ list $ \ params -> do
448 for_ list $ \ params -> do
485 let
449 let
486− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
450+ toParam' bytes = (bytes,LibPQ.Binary)
487 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
451 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
488 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
452 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
489 case resultMaybe of
453 case resultMaybe of
490− Nothing -> throw $ ResultException
454+ Nothing -> error
491 "traversePrepared_: LibPQ.execParams returned no results"
455 "traversePrepared_: LibPQ.execParams returned no results"
492− Just result -> okResult_ result
456+ Just _result -> return ()
493 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
457 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
494 case deallocResultMaybe of
458 case deallocResultMaybe of
495− Nothing -> throw $ ResultException
459+ Nothing -> error
496 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
460 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
497− Just deallocResult -> okResult_ deallocResult
461+ Just deallocResult -> do
462+ status <- LibPQ.resultStatus deallocResult
463+ unless (status == LibPQ.CommandOk) . error $
464+ "traversePrepared: DEALLOCATE status " <> show status
498 return (K ())
465 return (K ())
499
466
500 liftPQ pq = PQ $ \ (K conn) -> do
467 liftPQ pq = PQ $ \ (K conn) -> do
501− y <- liftIO $ pq conn
468+ y <- liftBase $ pq conn
502 return (K y)
469 return (K y)
503
470
504−instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)
471+instance MonadPQ schema m => MonadPQ schema (IdentityT m)
505−instance MonadPQ schemas m => MonadPQ schemas (ReaderT r m)
472+instance MonadPQ schema m => MonadPQ schema (ReaderT r m)
506−instance MonadPQ schemas m => MonadPQ schemas (Strict.StateT s m)
473+instance MonadPQ schema m => MonadPQ schema (Strict.StateT s m)
507−instance MonadPQ schemas m => MonadPQ schemas (Lazy.StateT s m)
474+instance MonadPQ schema m => MonadPQ schema (Lazy.StateT s m)
508−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.WriterT w m)
475+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.WriterT w m)
509−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.WriterT w m)
476+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.WriterT w m)
510−instance MonadPQ schemas m => MonadPQ schemas (MaybeT m)
477+instance MonadPQ schema m => MonadPQ schema (MaybeT m)
511−instance MonadPQ schemas m => MonadPQ schemas (ExceptT e m)
478+instance MonadPQ schema m => MonadPQ schema (ExceptT e m)
512−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.RWST r w s m)
479+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.RWST r w s m)
513−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.RWST r w s m)
480+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.RWST r w s m)
514−instance MonadPQ schemas m => MonadPQ schemas (ContT r m)
481+instance MonadPQ schema m => MonadPQ schema (ContT r m)
515−
482+instance MonadPQ schema m => MonadPQ schema (ListT m)
483+
516−instance (Monad m, schemas0 ~ schemas1)
484+instance (Monad m, schema0 ~ schema1)
517− => Applicative (PQ schemas0 schemas1 m) where
485+ => Applicative (PQ schema0 schema1 m) where
518 pure x = PQ $ \ _conn -> pure (K x)
486 pure x = PQ $ \ _conn -> pure (K x)
519 (<*>) = pqAp
487 (<*>) = pqAp
520
488
521−instance (Monad m, schemas0 ~ schemas1)
489+instance (Monad m, schema0 ~ schema1)
522− => Monad (PQ schemas0 schemas1 m) where
490+ => Monad (PQ schema0 schema1 m) where
523 return = pure
491 return = pure
524 (>>=) = flip pqBind
492 (>>=) = flip pqBind
525
493
526−instance (Monad m, schemas0 ~ schemas1)
494+instance schema0 ~ schema1 => MFunctor (PQ schema0 schema1) where
527− => Fail.MonadFail (PQ schemas0 schemas1 m) where
528− fail = Fail.fail
529−
530−instance schemas0 ~ schemas1 => MFunctor (PQ schemas0 schemas1) where
531 hoist f (PQ pq) = PQ (f . pq)
495 hoist f (PQ pq) = PQ (f . pq)
532
496
533−instance schemas0 ~ schemas1 => MonadTrans (PQ schemas0 schemas1) where
497+instance schema0 ~ schema1 => MonadTrans (PQ schema0 schema1) where
534 lift m = PQ $ \ _conn -> do
498 lift m = PQ $ \ _conn -> do
535 x <- m
499 x <- m
536 return (K x)
500 return (K x)
537
501
538−instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where
502+instance schema0 ~ schema1 => MMonad (PQ schema0 schema1) where
539 embed f (PQ pq) = PQ $ \ conn -> do
503 embed f (PQ pq) = PQ $ \ conn -> do
540 evalPQ (f (pq conn)) conn
504 evalPQ (f (pq conn)) conn
541
505
542−instance (MonadIO m, schema0 ~ schema1)
506+instance (MonadBase b m, schema0 ~ schema1)
543− => MonadIO (PQ schema0 schema1 m) where
507+ => MonadBase b (PQ schema0 schema1 m) where
544− liftIO = lift . liftIO
508+ liftBase = lift . liftBase
545
509
546−instance (MonadUnliftIO m, schemas0 ~ schemas1)
510+-- | A snapshot of the state of a `PQ` computation.
547− => MonadUnliftIO (PQ schemas0 schemas1 m) where
511+type PQRun schema =
548− withRunInIO
512+ forall m x. Monad m => PQ schema schema m x -> m (K x schema)
549− :: ((forall a . PQ schemas0 schema1 m a -> IO a) -> IO b)
513+
550− -> PQ schemas0 schema1 m b
514+-- | Helper function in defining `MonadBaseControl` instance for `PQ`.
551− withRunInIO inner = PQ $ \conn ->
515+pqliftWith :: Functor m => (PQRun schema -> m a) -> PQ schema schema m a
552− withRunInIO $ \(run :: (forall x . m x -> IO x)) ->
516+pqliftWith f = PQ $ \ conn ->
553− K <$> inner (\pq -> run $ unK <$> unPQ pq conn)
517+ fmap K (f $ \ pq -> unPQ pq conn)
518+
519+instance (MonadBaseControl b m, schema0 ~ schema1)
520+ => MonadBaseControl b (PQ schema0 schema1 m) where
521+ type StM (PQ schema0 schema1 m) x = StM m (K x schema0)
522+ liftBaseWith f =
523+ pqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run
524+ restoreM = PQ . const . restoreM
554
525
555-- | Get a row corresponding to a given row number from a `LibPQ.Result`,
526-- | Get a row corresponding to a given row number from a `LibPQ.Result`,
556-- throwing an exception if the row number is out of bounds.
527-- throwing an exception if the row number is out of bounds.
557getRow
528getRow
558− :: (FromRow columns y, MonadIO io)
529+ :: (FromRow columns y, MonadBase IO io)
559 => LibPQ.Row
530 => LibPQ.Row
560 -- ^ row number
531 -- ^ row number
561 -> K LibPQ.Result columns
532 -> K LibPQ.Result columns
562 -- ^ result
533 -- ^ result
563 -> io y
534 -> io y
564−getRow r (K result :: K LibPQ.Result columns) = liftIO $ do
535+getRow r (K result :: K LibPQ.Result columns) = liftBase $ do
565 numRows <- LibPQ.ntuples result
536 numRows <- LibPQ.ntuples result
566− when (numRows < r) $ throw $ ResultException $
537+ when (numRows < r) $ error $
567− "getRow: expected at least " <> pack (show r) <> "rows but only saw "
538+ "getRow: expected at least " <> show r <> "rows but only saw "
568− <> pack (show numRows)
539+ <> show numRows
569 let len = fromIntegral (lengthSList (Proxy @columns))
540 let len = fromIntegral (lengthSList (Proxy @columns))
570 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
541 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
571 case fromList row' of
542 case fromList row' of
572− Nothing -> throw $ ResultException "getRow: found unexpected length"
543+ Nothing -> error "getRow: found unexpected length"
573− Just row -> case fromRow @columns row of
544+ Just row -> return $ fromRow @columns row
574− Left parseError -> throw $ ParseException $ "getRow: " <> parseError
575− Right y -> return y
576
545
577-- | Intended to be used for unfolding in streaming libraries, `nextRow`
546-- | Intended to be used for unfolding in streaming libraries, `nextRow`
578-- takes a total number of rows (which can be found with `ntuples`)
547-- takes a total number of rows (which can be found with `ntuples`)
579-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,
548-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,
580-- otherwise returning the row along with the next row number.
549-- otherwise returning the row along with the next row number.
581nextRow
550nextRow
582− :: (FromRow columns y, MonadIO io)
551+ :: (FromRow columns y, MonadBase IO io)
583 => LibPQ.Row -- ^ total number of rows
552 => LibPQ.Row -- ^ total number of rows
584 -> K LibPQ.Result columns -- ^ result
553 -> K LibPQ.Result columns -- ^ result
585 -> LibPQ.Row -- ^ row number
554 -> LibPQ.Row -- ^ row number
586 -> io (Maybe (LibPQ.Row,y))
555 -> io (Maybe (LibPQ.Row,y))
587nextRow total (K result :: K LibPQ.Result columns) r
556nextRow total (K result :: K LibPQ.Result columns) r
588− = liftIO $ if r >= total then return Nothing else do
557+ = liftBase $ if r >= total then return Nothing else do
589 let len = fromIntegral (lengthSList (Proxy @columns))
558 let len = fromIntegral (lengthSList (Proxy @columns))
590 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
559 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
591 case fromList row' of
560 case fromList row' of
592− Nothing -> throw $ ResultException "nextRow: found unexpected length"
561+ Nothing -> error "nextRow: found unexpected length"
593− Just row -> case fromRow @columns row of
594− Left parseError -> throw $ ParseException $ "nextRow: " <> parseError
595− Right y -> return $ Just (r+1, y)
562+ Just row -> return $ Just (r+1, fromRow @columns row)
596
563
597-- | Get all rows from a `LibPQ.Result`.
564-- | Get all rows from a `LibPQ.Result`.
598getRows
565getRows
599− :: (FromRow columns y, MonadIO io)
566+ :: (FromRow columns y, MonadBase IO io)
600 => K LibPQ.Result columns -- ^ result
567 => K LibPQ.Result columns -- ^ result
601 -> io [y]
568 -> io [y]
602−getRows (K result :: K LibPQ.Result columns) = liftIO $ do
569+getRows (K result :: K LibPQ.Result columns) = liftBase $ do
603 let len = fromIntegral (lengthSList (Proxy @columns))
570 let len = fromIntegral (lengthSList (Proxy @columns))
604 numRows <- LibPQ.ntuples result
571 numRows <- LibPQ.ntuples result
605 for [0 .. numRows - 1] $ \ r -> do
572 for [0 .. numRows - 1] $ \ r -> do
606 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
573 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
607 case fromList row' of
574 case fromList row' of
608− Nothing -> throw $ ResultException "getRows: found unexpected length"
575+ Nothing -> error "getRows: found unexpected length"
609− Just row -> case fromRow @columns row of
576+ Just row -> return $ fromRow @columns row
610− Left parseError -> throw $ ParseException $ "getRows: " <> parseError
611− Right y -> return y
612
577
613-- | Get the first row if possible from a `LibPQ.Result`.
578-- | Get the first row if possible from a `LibPQ.Result`.
614firstRow
579firstRow
615− :: (FromRow columns y, MonadIO io)
580+ :: (FromRow columns y, MonadBase IO io)
616 => K LibPQ.Result columns -- ^ result
581 => K LibPQ.Result columns -- ^ result
617 -> io (Maybe y)
582 -> io (Maybe y)
618−firstRow (K result :: K LibPQ.Result columns) = liftIO $ do
583+firstRow (K result :: K LibPQ.Result columns) = liftBase $ do
619 numRows <- LibPQ.ntuples result
584 numRows <- LibPQ.ntuples result
620 if numRows <= 0 then return Nothing else do
585 if numRows <= 0 then return Nothing else do
621 let len = fromIntegral (lengthSList (Proxy @columns))
586 let len = fromIntegral (lengthSList (Proxy @columns))
622 row' <- traverse (LibPQ.getvalue result 0) [0 .. len - 1]
587 row' <- traverse (LibPQ.getvalue result 0) [0 .. len - 1]
623 case fromList row' of
588 case fromList row' of
624− Nothing -> throw $ ResultException "firstRow: found unexpected length"
589+ Nothing -> error "firstRow: found unexpected length"
625− Just row -> case fromRow @columns row of
590+ Just row -> return . Just $ fromRow @columns row
626− Left parseError -> throw $ ParseException $ "firstRow: " <> parseError
627− Right y -> return $ Just y
628
591
629-- | Lifts actions on results from @LibPQ@.
592-- | Lifts actions on results from @LibPQ@.
630liftResult
593liftResult
631− :: MonadIO io
594+ :: MonadBase IO io
632 => (LibPQ.Result -> IO x)
595 => (LibPQ.Result -> IO x)
633 -> K LibPQ.Result results -> io x
596 -> K LibPQ.Result results -> io x
634−liftResult f (K result) = liftIO $ f result
597+liftResult f (K result) = liftBase $ f result
635
598
636-- | Returns the number of rows (tuples) in the query result.
599-- | Returns the number of rows (tuples) in the query result.
637−ntuples :: MonadIO io => K LibPQ.Result columns -> io LibPQ.Row
600+ntuples :: MonadBase IO io => K LibPQ.Result columns -> io LibPQ.Row
638ntuples = liftResult LibPQ.ntuples
601ntuples = liftResult LibPQ.ntuples
639
602
640-- | Returns the result status of the command.
603-- | Returns the result status of the command.
641−resultStatus :: MonadIO io => K LibPQ.Result results -> io LibPQ.ExecStatus
604+resultStatus :: MonadBase IO io => K LibPQ.Result results -> io LibPQ.ExecStatus
642resultStatus = liftResult LibPQ.resultStatus
605resultStatus = liftResult LibPQ.resultStatus
643
606
644-- | Returns the error message most recently generated by an operation
607-- | Returns the error message most recently generated by an operation
645-- on the connection.
608-- on the connection.
646resultErrorMessage
609resultErrorMessage
647− :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)
610+ :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)
648resultErrorMessage = liftResult LibPQ.resultErrorMessage
611resultErrorMessage = liftResult LibPQ.resultErrorMessage
649−
650−-- | Returns the error code most recently generated by an operation
651−-- on the connection.
652−--
653−-- https://www.postgresql.org/docs/current/static/errcodes-appendix.html
654−resultErrorCode
655− :: MonadIO io
656− => K LibPQ.Result results
657− -> io (Maybe ByteString)
658−resultErrorCode = liftResult (flip LibPQ.resultErrorField LibPQ.DiagSqlstate)
659−
660−-- | the state of LibPQ
661−data PQState = PQState
662− { sqlExecStatus :: LibPQ.ExecStatus
663− , sqlStateCode :: Maybe ByteString
664− -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html
665− , sqlErrorMessage :: Maybe ByteString
666− } deriving (Eq, Show)
667−
668−-- | `Exception`s that can be thrown by Squeal.
669−data SquealException
670− = PQException PQState
671− | ResultException Text
672− | ParseException Text
673− deriving (Eq, Show)
674−instance Exception SquealException
675−
676−okResult_ :: MonadIO io => LibPQ.Result -> io ()
677−okResult_ result = liftIO $ do
678− status <- LibPQ.resultStatus result
679− case status of
680− LibPQ.CommandOk -> return ()
681− LibPQ.TuplesOk -> return ()
682− _ -> do
683− stateCode <- LibPQ.resultErrorField result LibPQ.DiagSqlstate
684− msg <- LibPQ.resultErrorMessage result
685− throw . PQException $ PQState status stateCode msg
686−
687−-- | Check if a `LibPQ.Result`'s status is either `LibPQ.CommandOk`
688−-- or `LibPQ.TuplesOk` otherwise `throw` a `PQException`.
689−okResult :: MonadIO io => K LibPQ.Result row -> io ()
690−okResult = okResult_ . unK
691−
692−-- | Catch `SquealException`s.
693−catchSqueal
694− :: MonadUnliftIO io
695− => io a
696− -> (SquealException -> io a) -- ^ handler
697− -> io a
698−catchSqueal = catch
699−
700−-- | Handle `SquealException`s.
701−handleSqueal
702− :: MonadUnliftIO io
703− => (SquealException -> io a) -- ^ handler
704− -> io a -> io a
705−handleSqueal = handle
706−
707−-- | `Either` return a `SquealException` or a result.
708−trySqueal
709− :: MonadUnliftIO io
710− => io a
711− -> io (Either SquealException a)
712−trySqueal = try
squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+79−69
@@ -1,40 +1,17 @@
1{-|
1{-|
2−Module: Squeal.PostgreSQL.Pool
2+Module: Squeal.PostgreSQL.Definition
3−Description: Connection pools
3+Description: Pooled connections
4Copyright: (c) Eitan Chatav, 2017
4Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
8−Connection pools.
8+A `MonadPQ` for pooled connections.
9−
10−Typical use case would be to create your pool using `createConnectionPool`
11−and run anything that requires the pool connection with `usingConnectionPool`.
12−
13−Here's a simplified example:
14−
15−>>> import Squeal.PostgreSQL
16−
17−>>> :{
18−do
19− let
20− query :: Query_ (Public '[]) () (Only Char)
21− query = values_ (literal 'a' `as` #fromOnly)
22− pool <- createConnectionPool "host=localhost port=5432 dbname=exampledb" 1 0.5 10
23− chr <- usingConnectionPool pool $ do
24− result <- runQuery query
25− Just (Only a) <- firstRow result
26− return a
27− destroyConnectionPool pool
28− putChar chr
29−:}
30−a
31-}
9-}
32
10
33{-# LANGUAGE
11{-# LANGUAGE
34 DeriveFunctor
12 DeriveFunctor
35 , FlexibleContexts
13 , FlexibleContexts
36 , FlexibleInstances
14 , FlexibleInstances
37− , InstanceSigs
38 , MultiParamTypeClasses
15 , MultiParamTypeClasses
39 , RankNTypes
16 , RankNTypes
40 , ScopedTypeVariables
17 , ScopedTypeVariables
@@ -45,24 +22,34 @@ a
45
22
46module Squeal.PostgreSQL.Pool
23module Squeal.PostgreSQL.Pool
47 ( -- * Pools
24 ( -- * Pools
48− Pool
25+ PoolPQ (..)
49 , createConnectionPool
26 , createConnectionPool
50− , usingConnectionPool
27+ , Pool
51− , destroyConnectionPool
28+ , destroyAllResources
29+ , PoolPQRun
30+ , poolpqliftWith
52 ) where
31 ) where
53
32
33+import Control.Monad.Base
34+import Control.Monad.Trans
35+import Control.Monad.Trans.Control
54import Data.ByteString
36import Data.ByteString
37+import Data.Pool
55import Data.Time
38import Data.Time
56−import Generics.SOP (K(..), unK)
39+import Generics.SOP (K(..))
57−import UnliftIO (MonadUnliftIO (..))
58−import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)
59
40
60import Squeal.PostgreSQL.PQ
41import Squeal.PostgreSQL.PQ
42+import Squeal.PostgreSQL.Schema
43+
44+-- | `PoolPQ` @schema@ should be a drop-in replacement for `PQ` @schema schema@.
45+newtype PoolPQ (schema :: SchemaType) m x =
46+ PoolPQ { runPoolPQ :: Pool (K Connection schema) -> m x }
47+ deriving Functor
61
48
62-- | Create a striped pool of connections.
49-- | Create a striped pool of connections.
63-- Although the garbage collector will destroy all idle connections when the pool is garbage collected it's recommended to manually `destroyAllResources` when you're done with the pool so that the connections are freed up as soon as possible.
50-- Although the garbage collector will destroy all idle connections when the pool is garbage collected it's recommended to manually `destroyAllResources` when you're done with the pool so that the connections are freed up as soon as possible.
64createConnectionPool
51createConnectionPool
65− :: MonadUnliftIO io
52+ :: MonadBase IO io
66 => ByteString
53 => ByteString
67 -- ^ The passed string can be empty to use all default parameters, or it can
54 -- ^ The passed string can be empty to use all default parameters, or it can
68 -- contain one or more parameter settings separated by whitespace.
55 -- contain one or more parameter settings separated by whitespace.
@@ -78,45 +65,68 @@ createConnectionPool
78 -> Int
65 -> Int
79 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.
66 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.
80 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.
67 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.
81− -> io (Pool (K Connection schemas))
68+ -> io (Pool (K Connection schema))
82−createConnectionPool conninfo stripes idle maxResrc =
69+createConnectionPool conninfo stripes idle maxResrc = liftBase $
83 createPool (connectdb conninfo) finish stripes idle maxResrc
70 createPool (connectdb conninfo) finish stripes idle maxResrc
84
71
85−{-|
72+-- | `Applicative` instance for `PoolPQ`.
86−Temporarily take a connection from a `Pool`, perform an action with it,
73+instance Monad m => Applicative (PoolPQ schema m) where
87−and return it to the pool afterwards.
74+ pure x = PoolPQ $ \ _ -> pure x
75+ PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do
76+ f' <- f pool
77+ x' <- x pool
78+ return $ f' x'
88
79
89−If the pool has an idle connection available, it is used immediately.
80+-- | `Monad` instance for `PoolPQ`.
90−Otherwise, if the maximum number of connections has not yet been reached,
81+instance Monad m => Monad (PoolPQ schema m) where
91−a new connection is created and used.
82+ return = pure
92−If the maximum number of connections has been reached, this function blocks
83+ PoolPQ x >>= f = PoolPQ $ \ pool -> do
93−until a connection becomes available.
84+ x' <- x pool
94−-}
85+ runPoolPQ (f x') pool
95−usingConnectionPool
96− :: MonadUnliftIO io
97− => Pool (K Connection schemas) -- ^ pool
98− -> PQ schemas schemas io x -- ^ session
99− -> io x
100−usingConnectionPool pool (PQ session) = unK <$> withResource pool session
101
86
102−{- |
87+-- | `MonadTrans` instance for `PoolPQ`.
103−Destroy all connections in all stripes in the pool.
88+instance MonadTrans (PoolPQ schema) where
104−Note that this will ignore any exceptions in the destroy function.
89+ lift m = PoolPQ $ \ _pool -> m
105
90
106−This function is useful when you detect that all connections
91+-- | `MonadBase` instance for `PoolPQ`.
107−in the pool are broken. For example after a database has been
92+instance MonadBase b m => MonadBase b (PoolPQ schema m) where
108−restarted all connections opened before the restart will be broken.
93+ liftBase = lift . liftBase
109−In that case it's better to close those connections so that
110−`usingConnectionPool` won't take a broken connection from the pool
111−but will open a new connection instead.
112
94
113−Another use-case for this function is that when you know you are done
95+-- | `MonadPQ` instance for `PoolPQ`.
114−with the pool you can destroy all idle connections immediately
96+instance MonadBaseControl IO io => MonadPQ schema (PoolPQ schema io) where
115−instead of waiting on the garbage collector to destroy them,
97+ manipulateParams manipulation params = PoolPQ $ \ pool -> do
116−thus freeing up those connections sooner.
98+ withResource pool $ \ conn -> do
117−-}
99+ (K result :: K (K Result ys) schema) <- flip unPQ conn $
118−destroyConnectionPool
100+ manipulateParams manipulation params
119− :: MonadUnliftIO io
101+ return result
120− => Pool (K Connection schemas) -- ^ pool
102+ traversePrepared manipulation params = PoolPQ $ \ pool ->
121− -> io ()
103+ withResource pool $ \ conn -> do
122−destroyConnectionPool = destroyAllResources
104+ (K result :: K (list (K Result ys)) schema) <- flip unPQ conn $
105+ traversePrepared manipulation params
106+ return result
107+ traversePrepared_ manipulation params = PoolPQ $ \ pool -> do
108+ withResource pool $ \ conn -> do
109+ (_ :: K () schema) <- flip unPQ conn $
110+ traversePrepared_ manipulation params
111+ return ()
112+ liftPQ m = PoolPQ $ \ pool ->
113+ withResource pool $ \ conn -> do
114+ (K result :: K result schema) <- flip unPQ conn $
115+ liftPQ m
116+ return result
117+
118+-- | A snapshot of the state of a `PoolPQ` computation.
119+type PoolPQRun schema =
120+ forall m x. Monad m => PoolPQ schema m x -> m x
121+
122+-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.
123+poolpqliftWith :: Functor m => (PoolPQRun schema -> m a) -> PoolPQ schema m a
124+poolpqliftWith f = PoolPQ $ \ pool ->
125+ (f $ \ pq -> runPoolPQ pq pool)
126+
127+-- | `MonadBaseControl` instance for `PoolPQ`.
128+instance MonadBaseControl b m => MonadBaseControl b (PoolPQ schema m) where
129+ type StM (PoolPQ schema m) x = StM m x
130+ liftBaseWith f =
131+ poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run
132+ restoreM = PoolPQ . const . restoreM
squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+476−678
@@ -1,7 +1,7 @@
1{-|
1{-|
2Module: Squeal.PostgreSQL.Query
2Module: Squeal.PostgreSQL.Query
3Description: Squeal queries
3Description: Squeal queries
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
@@ -9,81 +9,75 @@ Squeal queries.
9-}
9-}
10
10
11{-# LANGUAGE
11{-# LANGUAGE
12− ConstraintKinds
13− , DeriveGeneric
12+ DeriveGeneric
14 , FlexibleContexts
13 , FlexibleContexts
15− , FlexibleInstances
16 , GADTs
14 , GADTs
17 , GeneralizedNewtypeDeriving
15 , GeneralizedNewtypeDeriving
18 , LambdaCase
16 , LambdaCase
19− , MultiParamTypeClasses
20− , OverloadedLabels
21 , OverloadedStrings
17 , OverloadedStrings
22− , QuantifiedConstraints
23− , ScopedTypeVariables
24 , StandaloneDeriving
18 , StandaloneDeriving
25− , TypeApplications
26− , TypeFamilies
27 , TypeInType
19 , TypeInType
28 , TypeOperators
20 , TypeOperators
29− , RankNTypes
30− , UndecidableInstances
31− #-}
21+#-}
32
22
33module Squeal.PostgreSQL.Query
23module Squeal.PostgreSQL.Query
34 ( -- * Queries
24 ( -- * Queries
35− Query_
25+ Query (UnsafeQuery, renderQuery)
36− , Query (..)
37− -- ** Select
38− , select
39− , select_
40− , selectDistinct
41− , selectDistinct_
42− , selectDistinctOn
43− , selectDistinctOn_
44− , Selection (..)
45− -- ** Values
46− , values
47− , values_
48− -- ** Set Operations
49 , union
26 , union
50 , unionAll
27 , unionAll
51 , intersect
28 , intersect
52 , intersectAll
29 , intersectAll
53 , except
30 , except
54 , exceptAll
31 , exceptAll
55− -- ** With
32+ -- * Select
56− , With (..)
33+ , select
57− , CommonTableExpression (..)
34+ , selectDistinct
58− , withRecursive
35+ , selectStar
36+ , selectDistinctStar
37+ , selectDotStar
38+ , selectDistinctDotStar
39+ , values
40+ , values_
59 -- * Table Expressions
41 -- * Table Expressions
60 , TableExpression (..)
42 , TableExpression (..)
43+ , renderTableExpression
61 , from
44 , from
62 , where_
45 , where_
63− , groupBy
46+ , group
64 , having
47 , having
48+ , orderBy
65 , limit
49 , limit
66 , offset
50 , offset
51+ -- ** JSON table expressions
52+ , PGjson_each
53+ , PGjsonb_each
54+ , jsonEach
55+ , jsonbEach
67− -- * From Clauses
56+ -- * From
68 , FromClause (..)
57 , FromClause (..)
69 , table
58 , table
70 , subquery
59 , subquery
71 , view
60 , view
72− , common
73 , crossJoin
61 , crossJoin
74 , innerJoin
62 , innerJoin
75 , leftOuterJoin
63 , leftOuterJoin
76 , rightOuterJoin
64 , rightOuterJoin
77 , fullOuterJoin
65 , fullOuterJoin
78 -- * Grouping
66 -- * Grouping
79− , By (..)
67+ , By (By, By2)
68+ , renderBy
80− , GroupByClause (..)
69+ , GroupByClause (NoGroups, Group)
70+ , renderGroupByClause
81− , HavingClause (..)
71+ , HavingClause (NoHaving, Having)
72+ , renderHavingClause
73+ -- * Sorting
74+ , SortExpression (..)
75+ , renderSortExpression
82 ) where
76 ) where
83
77
84import Control.DeepSeq
78import Control.DeepSeq
85import Data.ByteString (ByteString)
79import Data.ByteString (ByteString)
86−import Data.Kind (Type)
80+import Data.Monoid hiding (All)
87import Data.String
81import Data.String
88import Data.Word
82import Data.Word
89import Generics.SOP hiding (from)
83import Generics.SOP hiding (from)
@@ -91,76 +85,25 @@ import GHC.TypeLits
91
85
92import qualified GHC.Generics as GHC
86import qualified GHC.Generics as GHC
93
87
94−import Squeal.PostgreSQL.Alias
95import Squeal.PostgreSQL.Expression
88import Squeal.PostgreSQL.Expression
96−import Squeal.PostgreSQL.Expression.Logic
97−import Squeal.PostgreSQL.Expression.Sort
98−import Squeal.PostgreSQL.Expression.Window
99−import Squeal.PostgreSQL.List
100−import Squeal.PostgreSQL.PG
101import Squeal.PostgreSQL.Render
89import Squeal.PostgreSQL.Render
102import Squeal.PostgreSQL.Schema
90import Squeal.PostgreSQL.Schema
103
91
104−-- $setup
105−-- >>> import Squeal.PostgreSQL
106−-- >>> import Data.Int (Int32, Int64)
107−-- >>> import Data.Monoid (Sum (..))
108−-- >>> import Data.Text (Text)
109−-- >>> import qualified Generics.SOP as SOP
110−
111{- |
92{- |
112−The process of retrieving or the command to retrieve data from
93+The process of retrieving or the command to retrieve data from a database
113−a database is called a `Query`.
94+is called a `Query`. The `select`, `selectStar`, `selectDotStar`,
114−
95+`selectDistinct`, `selectDistinctStar` and `selectDistinctDotStar` commands
115−The general `Query` type is parameterized by
96+are used to specify queries.
116−
117−* @outer :: FromType@ - outer scope for a correlated subquery,
118−* @commons :: FromType@ - scope for all `common` table expressions,
119−* @schemas :: SchemasType@ - scope for all `table`s and `view`s,
120−* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,
121−* @row :: RowType@ - return type of the `Query`.
122−-}
123−newtype Query
124− (outer :: FromType)
125− (commons :: FromType)
126− (schemas :: SchemasType)
127− (params :: [NullityType])
128− (row :: RowType)
129− = UnsafeQuery { renderQuery :: ByteString }
130− deriving (GHC.Generic,Show,Eq,Ord,NFData)
131−instance RenderSQL (Query outer commons schemas params row) where renderSQL = renderQuery
132−
133−{- |
134−The top level `Query_` type is parameterized by a @schemas@ `SchemasType`,
135−against which the query is type-checked, an input @parameters@ Haskell `Type`,
136−and an ouput row Haskell `Type`.
137−
138−A top-level query can be run
139−using `Squeal.PostgreSQL.PQ.runQueryParams`, or if @parameters = ()@
140−using `Squeal.PostgreSQL.PQ.runQuery`.
141−
142−Generally, @parameters@ will be a Haskell tuple or record whose entries
143−may be referenced using positional
144−`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a
145−Haskell record, whose entries will be targeted using overloaded labels.
146−
147−Let's see some examples of queries.
148−
149−>>> :set -XDeriveAnyClass -XDerivingStrategies
150−>>> :{
151−data Row a b = Row { col1 :: a, col2 :: b }
152− deriving stock (GHC.Generic)
153− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)
154−:}
155
97
156simple query:
98simple query:
157
99
158−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]
159−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
160>>> :{
100>>> :{
161let
101let
162− query :: Query_ (Public Schema) () (Row Int32 Int32)
102+ query :: Query
103+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
104+ '[]
105+ '["col" ::: 'Null 'PGint4]
163− query = select Star (from (table #tab))
106+ query = selectStar (from (table #tab))
164in printSQL query
107in printSQL query
165:}
108:}
166SELECT * FROM "tab" AS "tab"
109SELECT * FROM "tab" AS "tab"
@@ -169,22 +112,34 @@ restricted query:
169
112
170>>> :{
113>>> :{
171let
114let
172− query :: Query_ (Public Schema) () (Row Int32 Int32)
115+ query :: Query
116+ '[ "tab" ::: 'Table ('[] :=>
117+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
118+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
119+ '[]
120+ '[ "sum" ::: 'NotNull 'PGint4
121+ , "col1" ::: 'NotNull 'PGint4 ]
173 query =
122 query =
123+ select
174− select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)
124+ ((#col1 + #col2) `As` #sum :* #col1 :* Nil)
175 ( from (table #tab)
125 ( from (table #tab)
176 & where_ (#col1 .> #col2)
126 & where_ (#col1 .> #col2)
177 & where_ (#col2 .> 0) )
127 & where_ (#col2 .> 0) )
178in printSQL query
128in printSQL query
179:}
129:}
180−SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
130+SELECT ("col1" + "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
181
131
182subquery:
132subquery:
183
133
184>>> :{
134>>> :{
185let
135let
186− query :: Query_ (Public Schema) () (Row Int32 Int32)
136+ query :: Query
137+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
138+ '[]
139+ '["col" ::: 'Null 'PGint4]
140+ query =
141+ selectStar
187− query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))
142+ (from (subquery (selectStar (from (table #tab)) `As` #sub)))
188in printSQL query
143in printSQL query
189:}
144:}
190SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"
145SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"
@@ -193,8 +148,12 @@ limits and offsets:
193
148
194>>> :{
149>>> :{
195let
150let
196− query :: Query_ (Public Schema) () (Row Int32 Int32)
151+ query :: Query
152+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
153+ '[]
154+ '["col" ::: 'Null 'PGint4]
155+ query = selectStar
197− query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)
156+ (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)
198in printSQL query
157in printSQL query
199:}
158:}
200SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4
159SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4
@@ -203,426 +162,276 @@ parameterized query:
203
162
204>>> :{
163>>> :{
205let
164let
206− query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)
165+ query :: Query
166+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGfloat8])]
167+ '[ 'NotNull 'PGfloat8]
168+ '["col" ::: 'NotNull 'PGfloat8]
169+ query = selectStar
207− query = select Star (from (table #tab) & where_ (#col1 .> param @1))
170+ (from (table #tab) & where_ (#col .> param @1))
208in printSQL query
171in printSQL query
209:}
172:}
210−SELECT * FROM "tab" AS "tab" WHERE ("col1" > ($1 :: int4))
173+SELECT * FROM "tab" AS "tab" WHERE ("col" > ($1 :: float8))
211
174
212aggregation query:
175aggregation query:
213
176
214>>> :{
177>>> :{
215let
178let
216− query :: Query_ (Public Schema) () (Row Int64 Int32)
179+ query :: Query
180+ '[ "tab" ::: 'Table ('[] :=>
181+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
182+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
183+ '[]
184+ '[ "sum" ::: 'NotNull 'PGint4
185+ , "col1" ::: 'NotNull 'PGint4 ]
217 query =
186 query =
218− select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)
187+ select (sum_ #col2 `As` #sum :* #col1 :* Nil)
219− ( from (table (#tab `as` #table1))
188+ ( from (table (#tab `As` #table1))
220− & groupBy #col1
189+ & group (By #col1 :* Nil)
221− & having (sum_ (Distinct #col2) .> 1) )
190+ & having (#col1 + sum_ #col2 .> 1) )
222in printSQL query
191in printSQL query
223:}
192:}
224−SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (sum(DISTINCT "col2") > 1)
193+SELECT sum("col2") AS "sum", "col1" AS "col1" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + sum("col2")) > 1)
225
194
226sorted query:
195sorted query:
227
196
228>>> :{
197>>> :{
229let
198let
230− query :: Query_ (Public Schema) () (Row Int32 Int32)
199+ query :: Query
200+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
201+ '[]
202+ '["col" ::: 'Null 'PGint4]
203+ query = selectStar
231− query = select Star (from (table #tab) & orderBy [#col1 & Asc])
204+ (from (table #tab) & orderBy [#col & AscNullsFirst])
232in printSQL query
205in printSQL query
233:}
206:}
234−SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC
207+SELECT * FROM "tab" AS "tab" ORDER BY "col" ASC NULLS FIRST
235
208
236joins:
209joins:
237
210
238−>>> :{
211+>>> :set -XFlexibleContexts
239−type OrdersColumns =
240− '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
241− , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4
242− , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4
243− , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4 ]
244−:}
245−
246−>>> :{
247−type OrdersConstraints =
248− '["pk_orders" ::: PrimaryKey '["id"]
249− ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]
250− ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"] ]
251−:}
252−
253−>>> type NamesColumns = '["id" ::: 'NoDef :=> 'NotNull 'PGint4, "name" ::: 'NoDef :=> 'NotNull 'PGtext]
254−>>> type CustomersConstraints = '["pk_customers" ::: PrimaryKey '["id"]]
255−>>> type ShippersConstraints = '["pk_shippers" ::: PrimaryKey '["id"]]
256−>>> :{
257−type OrdersSchema =
258− '[ "orders" ::: 'Table (OrdersConstraints :=> OrdersColumns)
259− , "customers" ::: 'Table (CustomersConstraints :=> NamesColumns)
260− , "shippers" ::: 'Table (ShippersConstraints :=> NamesColumns) ]
261−:}
262−
263−>>> :{
264−data Order = Order
265− { price :: Float
266− , customerName :: Text
267− , shipperName :: Text
268− } deriving GHC.Generic
269−instance SOP.Generic Order
270−instance SOP.HasDatatypeInfo Order
271−:}
272−
273>>> :{
212>>> :{
274let
213let
275− query :: Query_ (Public OrdersSchema) () Order
214+ query :: Query
215+ '[ "orders" ::: 'Table (
216+ '["pk_orders" ::: PrimaryKey '["id"]
217+ ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]
218+ ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"]] :=>
219+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
220+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4
221+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4
222+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4
223+ ])
224+ , "customers" ::: 'Table (
225+ '["pk_customers" ::: PrimaryKey '["id"]] :=>
226+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
227+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
228+ ])
229+ , "shippers" ::: 'Table (
230+ '["pk_shippers" ::: PrimaryKey '["id"]] :=>
231+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
232+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
233+ ])
234+ ]
235+ '[]
236+ '[ "order_price" ::: 'NotNull 'PGfloat4
237+ , "customer_name" ::: 'NotNull 'PGtext
238+ , "shipper_name" ::: 'NotNull 'PGtext
239+ ]
276− query = select_
240+ query = select
277− ( #o ! #price `as` #price :*
241+ ( #o ! #price `As` #order_price :*
278− #c ! #name `as` #customerName :*
242+ #c ! #name `As` #customer_name :*
279− #s ! #name `as` #shipperName )
243+ #s ! #name `As` #shipper_name :* Nil )
280− ( from (table (#orders `as` #o)
244+ ( from (table (#orders `As` #o)
281− & innerJoin (table (#customers `as` #c))
245+ & innerJoin (table (#customers `As` #c))
282 (#o ! #customer_id .== #c ! #id)
246 (#o ! #customer_id .== #c ! #id)
283− & innerJoin (table (#shippers `as` #s))
247+ & innerJoin (table (#shippers `As` #s))
284 (#o ! #shipper_id .== #s ! #id)) )
248 (#o ! #shipper_id .== #s ! #id)) )
285in printSQL query
249in printSQL query
286:}
250:}
287−SELECT "o"."price" AS "price", "c"."name" AS "customerName", "s"."name" AS "shipperName" FROM "orders" AS "o" INNER JOIN "customers" AS "c" ON ("o"."customer_id" = "c"."id") INNER JOIN "shippers" AS "s" ON ("o"."shipper_id" = "s"."id")
251+SELECT "o"."price" AS "order_price", "c"."name" AS "customer_name", "s"."name" AS "shipper_name" FROM "orders" AS "o" INNER JOIN "customers" AS "c" ON ("o"."customer_id" = "c"."id") INNER JOIN "shippers" AS "s" ON ("o"."shipper_id" = "s"."id")
288
252
289self-join:
253self-join:
290
254
291>>> :{
255>>> :{
292let
256let
293− query :: Query_ (Public Schema) () (Row Int32 Int32)
257+ query :: Query
294− query = select
258+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
295− (#t1 & DotStar)
259+ '[]
260+ '["col" ::: 'Null 'PGint4]
261+ query = selectDotStar #t1
296− (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))
262+ (from (table (#tab `As` #t1) & crossJoin (table (#tab `As` #t2))))
297in printSQL query
263in printSQL query
298:}
264:}
299SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"
265SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"
300
266
301−value queries:
302−
303−>>> :{
304−let
305− query :: Query_ schemas () (Row String Bool)
306− query = values
307− ("true" `as` #col1 :* true `as` #col2)
308− ["false" `as` #col1 :* false `as` #col2]
309−in printSQL query
310−:}
311−SELECT * FROM (VALUES (E'true', TRUE), (E'false', FALSE)) AS t ("col1", "col2")
312−
313set operations:
267set operations:
314
268
315>>> :{
269>>> :{
316let
270let
317− query :: Query_ (Public Schema) () (Row Int32 Int32)
271+ query :: Query
318− query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))
272+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
319−in printSQL query
273+ '[]
320−:}
274+ '["col" ::: 'Null 'PGint4]
321−(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")
322−
323−with queries:
324−
325−>>> :{
326−let
327− query :: Query_ (Public Schema) () (Row Int32 Int32)
328− query = with (
329− select Star (from (table #tab)) `as` #cte1 :>>
330− select Star (from (common #cte1)) `as` #cte2
331− ) (select Star (from (common #cte2)))
332−in printSQL query
333−:}
334−WITH "cte1" AS (SELECT * FROM "tab" AS "tab"), "cte2" AS (SELECT * FROM "cte1" AS "cte1") SELECT * FROM "cte2" AS "cte2"
335−
336−window function queries
337−
338−>>> :{
339−let
340− query :: Query_ (Public Schema) () (Row Int32 Int64)
341− query = select
342− (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))
343− (from (table #tab))
344−in printSQL query
345−:}
346−SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "col2" FROM "tab" AS "tab"
347−
348−correlated subqueries
349−
350−>>> :{
351−let
352− query :: Query_ (Public Schema) () (Only Int32)
353 query =
275 query =
354− select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))
276+ selectStar (from (table #tab))
355− & where_ (exists (
277+ `unionAll`
356− select Star (from (table (#tab `as` #t2))
278+ selectStar (from (table #tab))
357− & where_ (#t2 ! #col2 .== #t1 ! #col1)))))
358in printSQL query
279in printSQL query
359:}
280:}
360−SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))
281+(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")
361−
362-}
282-}
363−type family Query_
283+newtype Query
364− (schemas :: SchemasType)
284+ (schema :: SchemaType)
365− (parameters :: Type)
285+ (params :: [NullityType])
366− (row :: Type) where
286+ (columns :: RelationType)
367− Query_ schemas params row =
287+ = UnsafeQuery { renderQuery :: ByteString }
368− Query '[] '[] schemas (TuplePG params) (RowPG row)
288+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
289+instance RenderSQL (Query schema params columns) where renderSQL = renderQuery
369
290
370-- | The results of two queries can be combined using the set operation
291-- | The results of two queries can be combined using the set operation
371-- `union`. Duplicate rows are eliminated.
292-- `union`. Duplicate rows are eliminated.
372union
293union
373− :: Query outer commons schemas params columns
294+ :: Query schema params columns
374− -> Query outer commons schemas params columns
295+ -> Query schema params columns
375− -> Query outer commons schemas params columns
296+ -> Query schema params columns
376q1 `union` q2 = UnsafeQuery $
297q1 `union` q2 = UnsafeQuery $
377− parenthesized (renderSQL q1)
298+ parenthesized (renderQuery q1)
378 <+> "UNION"
299 <+> "UNION"
379− <+> parenthesized (renderSQL q2)
300+ <+> parenthesized (renderQuery q2)
380
301
381-- | The results of two queries can be combined using the set operation
302-- | The results of two queries can be combined using the set operation
382-- `unionAll`, the disjoint union. Duplicate rows are retained.
303-- `unionAll`, the disjoint union. Duplicate rows are retained.
383unionAll
304unionAll
384− :: Query outer commons schemas params columns
305+ :: Query schema params columns
385− -> Query outer commons schemas params columns
306+ -> Query schema params columns
386− -> Query outer commons schemas params columns
307+ -> Query schema params columns
387q1 `unionAll` q2 = UnsafeQuery $
308q1 `unionAll` q2 = UnsafeQuery $
388− parenthesized (renderSQL q1)
309+ parenthesized (renderQuery q1)
389 <+> "UNION" <+> "ALL"
310 <+> "UNION" <+> "ALL"
390− <+> parenthesized (renderSQL q2)
311+ <+> parenthesized (renderQuery q2)
391
312
392-- | The results of two queries can be combined using the set operation
313-- | The results of two queries can be combined using the set operation
393-- `intersect`, the intersection. Duplicate rows are eliminated.
314-- `intersect`, the intersection. Duplicate rows are eliminated.
394intersect
315intersect
395− :: Query outer commons schemas params columns
316+ :: Query schema params columns
396− -> Query outer commons schemas params columns
317+ -> Query schema params columns
397− -> Query outer commons schemas params columns
318+ -> Query schema params columns
398q1 `intersect` q2 = UnsafeQuery $
319q1 `intersect` q2 = UnsafeQuery $
399− parenthesized (renderSQL q1)
320+ parenthesized (renderQuery q1)
400 <+> "INTERSECT"
321 <+> "INTERSECT"
401− <+> parenthesized (renderSQL q2)
322+ <+> parenthesized (renderQuery q2)
402
323
403-- | The results of two queries can be combined using the set operation
324-- | The results of two queries can be combined using the set operation
404-- `intersectAll`, the intersection. Duplicate rows are retained.
325-- `intersectAll`, the intersection. Duplicate rows are retained.
405intersectAll
326intersectAll
406− :: Query outer commons schemas params columns
327+ :: Query schema params columns
407− -> Query outer commons schemas params columns
328+ -> Query schema params columns
408− -> Query outer commons schemas params columns
329+ -> Query schema params columns
409q1 `intersectAll` q2 = UnsafeQuery $
330q1 `intersectAll` q2 = UnsafeQuery $
410− parenthesized (renderSQL q1)
331+ parenthesized (renderQuery q1)
411 <+> "INTERSECT" <+> "ALL"
332 <+> "INTERSECT" <+> "ALL"
412− <+> parenthesized (renderSQL q2)
333+ <+> parenthesized (renderQuery q2)
413
334
414-- | The results of two queries can be combined using the set operation
335-- | The results of two queries can be combined using the set operation
415-- `except`, the set difference. Duplicate rows are eliminated.
336-- `except`, the set difference. Duplicate rows are eliminated.
416except
337except
417− :: Query outer commons schemas params columns
338+ :: Query schema params columns
418− -> Query outer commons schemas params columns
339+ -> Query schema params columns
419− -> Query outer commons schemas params columns
340+ -> Query schema params columns
420q1 `except` q2 = UnsafeQuery $
341q1 `except` q2 = UnsafeQuery $
421− parenthesized (renderSQL q1)
342+ parenthesized (renderQuery q1)
422 <+> "EXCEPT"
343 <+> "EXCEPT"
423− <+> parenthesized (renderSQL q2)
344+ <+> parenthesized (renderQuery q2)
424
345
425-- | The results of two queries can be combined using the set operation
346-- | The results of two queries can be combined using the set operation
426-- `exceptAll`, the set difference. Duplicate rows are retained.
347-- `exceptAll`, the set difference. Duplicate rows are retained.
427exceptAll
348exceptAll
428− :: Query outer commons schemas params columns
349+ :: Query schema params columns
429− -> Query outer commons schemas params columns
350+ -> Query schema params columns
430− -> Query outer commons schemas params columns
351+ -> Query schema params columns
431q1 `exceptAll` q2 = UnsafeQuery $
352q1 `exceptAll` q2 = UnsafeQuery $
432− parenthesized (renderSQL q1)
353+ parenthesized (renderQuery q1)
433 <+> "EXCEPT" <+> "ALL"
354 <+> "EXCEPT" <+> "ALL"
434− <+> parenthesized (renderSQL q2)
355+ <+> parenthesized (renderQuery q2)
435
356
436{-----------------------------------------
357{-----------------------------------------
437SELECT queries
358SELECT queries
438-----------------------------------------}
359-----------------------------------------}
439
360
440−{- | The simplest kinds of `Selection` are `Star` and `DotStar` which
441−emits all columns that a `TableExpression` produces. A select `List`
442−is a list of `Expression`s. A `Selection` could be a list of
443−`WindowFunction`s `Over` `WindowDefinition`. `Additional` `Selection`s can
444−be selected with `Also`.
445−-}
446−data Selection outer commons grp schemas params from row where
447− Star
448− :: HasUnique tab from row
449− => Selection outer commons 'Ungrouped schemas params from row
450− -- ^ `HasUnique` table in the `FromClause`
451− DotStar
452− :: Has tab from row
453− => Alias tab
454− -- ^ `Has` table with `Alias`
455− -> Selection outer commons 'Ungrouped schemas params from row
456− List
457− :: SListI row
458− => NP (Aliased (Expression outer commons grp schemas params from)) row
459− -- ^ `NP` list of `Aliased` `Expression`s
460− -> Selection outer commons grp schemas params from row
461− Over
462− :: SListI row
463− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row
464− -- ^ `NP` list of `Aliased` `WindowFunction`s
465− -> WindowDefinition outer commons grp schemas params from
466− -> Selection outer commons grp schemas params from row
467− Also
468− :: Selection outer commons grp schemas params from right
469− -- ^ `Additional` `Selection`
470− -> Selection outer commons grp schemas params from left
471− -> Selection outer commons grp schemas params from (Join left right)
472−instance Additional (Selection outer commons grp schemas params from) where
473− also = Also
474−instance (KnownSymbol col, row ~ '[col ::: ty])
475− => Aliasable col
476− (Expression outer commons grp schemas params from ty)
477− (Selection outer commons grp schemas params from row) where
478− expr `as` col = List (expr `as` col)
479−instance (Has tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])
480− => IsQualified tab col
481− (Selection outer commons 'Ungrouped schemas params from row1) where
482− tab ! col = tab ! col `as` col
483−instance
484− ( Has tab (Join outer from) row0
485− , Has col row0 ty
486− , row1 ~ '[col ::: ty]
487− , GroupedBy tab col bys )
488− => IsQualified tab col
489− (Selection outer commons ('Grouped bys) schemas params from row1) where
490− tab ! col = tab ! col `as` col
491−instance (HasUnique tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])
492− => IsLabel col
493− (Selection outer commons 'Ungrouped schemas params from row1) where
494− fromLabel = fromLabel @col `as` Alias
495−instance
496− ( HasUnique tab (Join outer from) row0
497− , Has col row0 ty
498− , row1 ~ '[col ::: ty]
499− , GroupedBy tab col bys )
500− => IsLabel col
501− (Selection outer commons ('Grouped bys) schemas params from row1) where
502− fromLabel = fromLabel @col `as` Alias
503−
504−instance RenderSQL (Selection outer commons grp schemas params from row) where
505− renderSQL = \case
506− List list -> renderCommaSeparated (renderAliased renderSQL) list
507− Star -> "*"
508− DotStar tab -> renderSQL tab <> ".*"
509− Also right left -> renderSQL left <> ", " <> renderSQL right
510− Over winFns winDef ->
511− let
512− renderOver
513− :: Aliased (WindowFunction outer commons grp schemas params from) field
514− -> ByteString
515− renderOver (winFn `As` col) = renderSQL winFn
516− <+> "OVER" <+> parenthesized (renderSQL winDef)
517− <+> "AS" <+> renderSQL col
518− in
519− renderCommaSeparated renderOver winFns
520−
521−instance IsString
522− (Selection outer commons grp schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where
523− fromString str = fromString str `as` Alias
524−
525-- | the `TableExpression` in the `select` command constructs an intermediate
361-- | the `TableExpression` in the `select` command constructs an intermediate
526-- virtual table by possibly combining tables, views, eliminating rows,
362-- virtual table by possibly combining tables, views, eliminating rows,
527-- grouping, etc. This table is finally passed on to processing by
363-- grouping, etc. This table is finally passed on to processing by
528−-- the select list. The `Selection` determines which columns of
364+-- the select list. The select list determines which columns of
529-- the intermediate table are actually output.
365-- the intermediate table are actually output.
530select
366select
531− :: (SListI row, row ~ (x ': xs))
367+ :: SListI columns
532− => Selection outer commons grp schemas params from row
533− -- ^ selection
534− -> TableExpression outer commons grp schemas params from
535− -- ^ intermediate virtual table
536− -> Query outer commons schemas params row
537−select selection tabexpr = UnsafeQuery $
538− "SELECT"
539− <+> renderSQL selection
540− <+> renderSQL tabexpr
541−
542−-- | Like `select` but takes an `NP` list of `Expression`s instead
543−-- of a general `Selection`.
544−select_
545− :: (SListI row, row ~ (x ': xs))
546− => NP (Aliased (Expression outer commons grp schemas params from)) row
368+ => NP (Aliased (Expression schema relations grouping params)) (column ': columns)
547 -- ^ select list
369 -- ^ select list
548− -> TableExpression outer commons grp schemas params from
370+ -> TableExpression schema params relations grouping
549 -- ^ intermediate virtual table
371 -- ^ intermediate virtual table
550− -> Query outer commons schemas params row
372+ -> Query schema params (column ': columns)
551−select_ = select . List
373+select list rels = UnsafeQuery $
374+ "SELECT"
375+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list
376+ <+> renderTableExpression rels
552
377
553-- | After the select list has been processed, the result table can
378-- | After the select list has been processed, the result table can
554-- be subject to the elimination of duplicate rows using `selectDistinct`.
379-- be subject to the elimination of duplicate rows using `selectDistinct`.
555selectDistinct
380selectDistinct
556− :: (SListI columns, columns ~ (col ': cols))
381+ :: SListI columns
557− => Selection outer commons grp schemas params from columns
382+ => NP (Aliased (Expression schema relations 'Ungrouped params)) (column ': columns)
558− -- ^ selection
383+ -- ^ select list
559− -> TableExpression outer commons grp schemas params from
384+ -> TableExpression schema params relations 'Ungrouped
560 -- ^ intermediate virtual table
385 -- ^ intermediate virtual table
561− -> Query outer commons schemas params columns
386+ -> Query schema params (column ': columns)
562−selectDistinct selection tabexpr = UnsafeQuery $
387+selectDistinct list rels = UnsafeQuery $
563 "SELECT DISTINCT"
388 "SELECT DISTINCT"
564− <+> renderSQL selection
389+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list
565− <+> renderSQL tabexpr
390+ <+> renderTableExpression rels
566−
391+
567−-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead
392+-- | The simplest kind of query is `selectStar` which emits all columns
568−-- of a general `Selection`.
393+-- that the table expression produces.
569−selectDistinct_
394+selectStar
570− :: (SListI columns, columns ~ (col ': cols))
395+ :: HasUnique relation relations columns
571− => NP (Aliased (Expression outer commons grp schemas params from)) columns
572− -- ^ select list
573− -> TableExpression outer commons grp schemas params from
396+ => TableExpression schema params relations 'Ungrouped
574 -- ^ intermediate virtual table
397 -- ^ intermediate virtual table
575− -> Query outer commons schemas params columns
398+ -> Query schema params columns
576−selectDistinct_ = selectDistinct . List
399+selectStar rels = UnsafeQuery $ "SELECT" <+> "*" <+> renderTableExpression rels
577−
400+
578−{-|
401+-- | A `selectDistinctStar` emits all columns that the table expression
579−`selectDistinctOn` keeps only the first row of each set of rows where
402+-- produces and eliminates duplicate rows.
580−the given expressions evaluate to equal. The DISTINCT ON expressions are
403+selectDistinctStar
581−interpreted using the same rules as for ORDER BY. ORDER BY is used to
404+ :: HasUnique relation relations columns
582−ensure that the desired row appears first.
583−
584−The DISTINCT ON expression(s) must match the leftmost ORDER BY expression(s).
585−The ORDER BY clause will normally contain additional expression(s) that
586−determine the desired precedence of rows within each DISTINCT ON group.
587−
588−In order to guarantee they match and reduce redundancy, this function
589−will prepend the The DISTINCT ON expressions to the ORDER BY clause.
590−-}
591−selectDistinctOn
592− :: (SListI columns, columns ~ (col ': cols))
593− => [SortExpression outer commons grp schemas params from]
594− -- ^ DISTINCT ON expression(s) and prepended to ORDER BY clause
595− -> Selection outer commons grp schemas params from columns
596− -- ^ selection
597− -> TableExpression outer commons grp schemas params from
405+ => TableExpression schema params relations 'Ungrouped
598 -- ^ intermediate virtual table
406 -- ^ intermediate virtual table
599− -> Query outer commons schemas params columns
407+ -> Query schema params columns
600−selectDistinctOn distincts selection tab = UnsafeQuery $
408+selectDistinctStar rels = UnsafeQuery $
601− "SELECT DISTINCT ON"
409+ "SELECT DISTINCT" <+> "*" <+> renderTableExpression rels
602− <+> parenthesized (commaSeparated (renderDistinctOn <$> distincts))
410+
603− <+> renderSQL selection
411+-- | When working with multiple tables, it can also be useful to ask
604− <+> renderSQL (tab {orderByClause = distincts <> orderByClause tab})
412+-- for all the columns of a particular table, using `selectDotStar`.
605− where
413+selectDotStar
606− renderDistinctOn = \case
414+ :: Has relation relations columns
607− Asc expression -> renderSQL expression
415+ => Alias relation
608− Desc expression -> renderSQL expression
416+ -- ^ particular virtual subtable
609− AscNullsFirst expression -> renderSQL expression
417+ -> TableExpression schema params relations 'Ungrouped
610− DescNullsFirst expression -> renderSQL expression
418+ -- ^ intermediate virtual table
611− AscNullsLast expression -> renderSQL expression
419+ -> Query schema params columns
612− DescNullsLast expression -> renderSQL expression
420+selectDotStar rel relations = UnsafeQuery $
613−
421+ "SELECT" <+> renderAlias rel <> ".*" <+> renderTableExpression relations
614−-- | Like `selectDistinctOn` but takes an `NP` list of `Expression`s instead
422+
615−-- of a general `Selection`.
423+-- | A `selectDistinctDotStar` asks for all the columns of a particular table,
616−selectDistinctOn_
424+-- and eliminates duplicate rows.
617− :: (SListI columns, columns ~ (col ': cols))
425+selectDistinctDotStar
618− => [SortExpression outer commons grp schemas params from]
426+ :: Has relation relations columns
619− -- ^ distinct on and return the first row in ordering
427+ => Alias relation
620− -> NP (Aliased (Expression outer commons grp schemas params from)) columns
428+ -- ^ particular virtual table
621− -- ^ selection
622− -> TableExpression outer commons grp schemas params from
429+ -> TableExpression schema params relations 'Ungrouped
623 -- ^ intermediate virtual table
430 -- ^ intermediate virtual table
624− -> Query outer commons schemas params columns
431+ -> Query schema params columns
625−selectDistinctOn_ distincts = selectDistinctOn distincts . List
432+selectDistinctDotStar rel relations = UnsafeQuery $
433+ "SELECT DISTINCT" <+> renderAlias rel <> ".*"
434+ <+> renderTableExpression relations
626
435
627-- | `values` computes a row value or set of row values
436-- | `values` computes a row value or set of row values
628-- specified by value expressions. It is most commonly used
437-- specified by value expressions. It is most commonly used
@@ -630,16 +439,16 @@ selectDistinctOn_ distincts = selectDistinctOn distincts . List
630-- but it can be used on its own.
439-- but it can be used on its own.
631--
440--
632-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]
441-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]
633−-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query outer commons schemas '[] Row
442+-- >>> let query = values (1 `As` #a :* "one" `As` #b :* Nil) [] :: Query '[] '[] Row
634-- >>> printSQL query
443-- >>> printSQL query
635-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")
444-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")
636values
445values
637 :: SListI cols
446 :: SListI cols
638− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
447+ => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols
639− -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]
448+ -> [NP (Aliased (Expression schema '[] 'Ungrouped params)) cols]
640 -- ^ When more than one row is specified, all the rows must
449 -- ^ When more than one row is specified, all the rows must
641 -- must have the same number of elements
450 -- must have the same number of elements
642− -> Query outer commons schemas params cols
451+ -> Query schema params cols
643values rw rws = UnsafeQuery $ "SELECT * FROM"
452values rw rws = UnsafeQuery $ "SELECT * FROM"
644 <+> parenthesized (
453 <+> parenthesized (
645 "VALUES"
454 "VALUES"
@@ -650,17 +459,17 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"
650 <+> parenthesized (renderCommaSeparated renderAliasPart rw)
459 <+> parenthesized (renderCommaSeparated renderAliasPart rw)
651 where
460 where
652 renderAliasPart, renderValuePart
461 renderAliasPart, renderValuePart
653− :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString
462+ :: Aliased (Expression schema '[] 'Ungrouped params) ty -> ByteString
654− renderAliasPart (_ `As` name) = renderSQL name
463+ renderAliasPart (_ `As` name) = renderAlias name
655− renderValuePart (value `As` _) = renderSQL value
464+ renderValuePart (value `As` _) = renderExpression value
656
465
657-- | `values_` computes a row value or set of row values
466-- | `values_` computes a row value or set of row values
658-- specified by value expressions.
467-- specified by value expressions.
659values_
468values_
660 :: SListI cols
469 :: SListI cols
661− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
470+ => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols
662 -- ^ one row of values
471 -- ^ one row of values
663− -> Query outer commons schemas params cols
472+ -> Query schema params cols
664values_ rw = values rw []
473values_ rw = values rw []
665
474
666{-----------------------------------------
475{-----------------------------------------
@@ -674,17 +483,15 @@ Table Expressions
674-- to a table on disk, a so-called base table, but more complex expressions
483-- to a table on disk, a so-called base table, but more complex expressions
675-- can be used to modify or combine base tables in various ways.
484-- can be used to modify or combine base tables in various ways.
676data TableExpression
485data TableExpression
677− (outer :: FromType)
486+ (schema :: SchemaType)
678− (commons :: FromType)
679− (grp :: Grouping)
680− (schemas :: SchemasType)
681 (params :: [NullityType])
487 (params :: [NullityType])
682− (from :: FromType)
488+ (relations :: RelationsType)
489+ (grouping :: Grouping)
683 = TableExpression
490 = TableExpression
684− { fromClause :: FromClause outer commons schemas params from
491+ { fromClause :: FromClause schema params relations
685 -- ^ A table reference that can be a table name, or a derived table such
492 -- ^ A table reference that can be a table name, or a derived table such
686 -- as a subquery, a @JOIN@ construct, or complex combinations of these.
493 -- as a subquery, a @JOIN@ construct, or complex combinations of these.
687− , whereClause :: [Condition outer commons 'Ungrouped schemas params from]
494+ , whereClause :: [Condition schema relations 'Ungrouped params]
688 -- ^ optional search coditions, combined with `.&&`. After the processing
495 -- ^ optional search coditions, combined with `.&&`. After the processing
689 -- of the `fromClause` is done, each row of the derived virtual table
496 -- of the `fromClause` is done, each row of the derived virtual table
690 -- is checked against the search condition. If the result of the
497 -- is checked against the search condition. If the result of the
@@ -693,20 +500,20 @@ data TableExpression
693 -- at least one column of the table generated in the `fromClause`;
500 -- at least one column of the table generated in the `fromClause`;
694 -- this is not required, but otherwise the WHERE clause will
501 -- this is not required, but otherwise the WHERE clause will
695 -- be fairly useless.
502 -- be fairly useless.
696− , groupByClause :: GroupByClause grp from
503+ , groupByClause :: GroupByClause relations grouping
697 -- ^ The `groupByClause` is used to group together those rows in a table
504 -- ^ The `groupByClause` is used to group together those rows in a table
698 -- that have the same values in all the columns listed. The order in which
505 -- that have the same values in all the columns listed. The order in which
699 -- the columns are listed does not matter. The effect is to combine each
506 -- the columns are listed does not matter. The effect is to combine each
700 -- set of rows having common values into one group row that represents all
507 -- set of rows having common values into one group row that represents all
701 -- rows in the group. This is done to eliminate redundancy in the output
508 -- rows in the group. This is done to eliminate redundancy in the output
702 -- and/or compute aggregates that apply to these groups.
509 -- and/or compute aggregates that apply to these groups.
703− , havingClause :: HavingClause outer commons grp schemas params from
510+ , havingClause :: HavingClause schema relations grouping params
704 -- ^ If a table has been grouped using `groupBy`, but only certain groups
511 -- ^ If a table has been grouped using `groupBy`, but only certain groups
705 -- are of interest, the `havingClause` can be used, much like a
512 -- are of interest, the `havingClause` can be used, much like a
706 -- `whereClause`, to eliminate groups from the result. Expressions in the
513 -- `whereClause`, to eliminate groups from the result. Expressions in the
707 -- `havingClause` can refer both to grouped expressions and to ungrouped
514 -- `havingClause` can refer both to grouped expressions and to ungrouped
708 -- expressions (which necessarily involve an aggregate function).
515 -- expressions (which necessarily involve an aggregate function).
709− , orderByClause :: [SortExpression outer commons grp schemas params from]
516+ , orderByClause :: [SortExpression schema relations grouping params]
710 -- ^ The `orderByClause` is for optional sorting. When more than one
517 -- ^ The `orderByClause` is for optional sorting. When more than one
711 -- `SortExpression` is specified, the later (right) values are used to sort
518 -- `SortExpression` is specified, the later (right) values are used to sort
712 -- rows that are equal according to the earlier (left) values.
519 -- rows that are equal according to the earlier (left) values.
@@ -716,69 +523,72 @@ data TableExpression
716 -- will be returned (but possibly fewer, if the query itself yields
523 -- will be returned (but possibly fewer, if the query itself yields
717 -- fewer rows).
524 -- fewer rows).
718 , offsetClause :: [Word64]
525 , offsetClause :: [Word64]
719− -- ^ The `offsetClause` is combined with `Prelude.+` to give an offset count
526+ -- ^ The `offsetClause` is combined with `+` to give an offset count
720 -- if nonempty. The offset count says to skip that many rows before
527 -- if nonempty. The offset count says to skip that many rows before
721 -- beginning to return rows. The rows are skipped before the limit count
528 -- beginning to return rows. The rows are skipped before the limit count
722 -- is applied.
529 -- is applied.
723− } deriving (GHC.Generic)
530+ }
724
531
725-- | Render a `TableExpression`
532-- | Render a `TableExpression`
726−instance RenderSQL (TableExpression outer commons grp schemas params from) where
533+renderTableExpression
727− renderSQL
534+ :: TableExpression schema params relations grouping
535+ -> ByteString
536+renderTableExpression
728− (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat
537+ (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat
729− [ "FROM ", renderSQL frm'
538+ [ "FROM ", renderFromClause frm'
730− , renderWheres whs'
539+ , renderWheres whs'
731− , renderSQL grps'
540+ , renderGroupByClause grps'
732− , renderSQL hvs'
541+ , renderHavingClause hvs'
733− , renderOrderByClause srts'
542+ , renderOrderByClause srts'
734− , renderLimits lims'
543+ , renderLimits lims'
735− , renderOffsets offs' ]
544+ , renderOffsets offs'
545+ ]
736− where
546+ where
737− renderWheres = \case
547+ renderWheres = \case
738− [] -> ""
548+ [] -> ""
739− wh:[] -> " WHERE" <+> renderSQL wh
549+ wh:[] -> " WHERE" <+> renderExpression wh
740− wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)
550+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)
741− renderOrderByClause = \case
551+ renderOrderByClause = \case
742− [] -> ""
552+ [] -> ""
743− srts -> " ORDER BY"
553+ srts -> " ORDER BY"
744− <+> commaSeparated (renderSQL <$> srts)
554+ <+> commaSeparated (renderSortExpression <$> srts)
745− renderLimits = \case
555+ renderLimits = \case
746− [] -> ""
556+ [] -> ""
747− lims -> " LIMIT" <+> fromString (show (minimum lims))
557+ lims -> " LIMIT" <+> fromString (show (minimum lims))
748− renderOffsets = \case
558+ renderOffsets = \case
749− [] -> ""
559+ [] -> ""
750− offs -> " OFFSET" <+> fromString (show (sum offs))
560+ offs -> " OFFSET" <+> fromString (show (sum offs))
751
561
752-- | A `from` generates a `TableExpression` from a table reference that can be
562-- | A `from` generates a `TableExpression` from a table reference that can be
753-- a table name, or a derived table such as a subquery, a JOIN construct,
563-- a table name, or a derived table such as a subquery, a JOIN construct,
754-- or complex combinations of these. A `from` may be transformed by `where_`,
564-- or complex combinations of these. A `from` may be transformed by `where_`,
755−-- `groupBy`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator
565+-- `group`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator
756-- to match the left-to-right sequencing of their placement in SQL.
566-- to match the left-to-right sequencing of their placement in SQL.
757from
567from
758− :: FromClause outer commons schemas params from -- ^ table reference
568+ :: FromClause schema params relations -- ^ table reference
759− -> TableExpression outer commons 'Ungrouped schemas params from
569+ -> TableExpression schema params relations 'Ungrouped
760−from tab = TableExpression tab [] noGroups NoHaving [] [] []
570+from rels = TableExpression rels [] NoGroups NoHaving [] [] []
761
571
762-- | A `where_` is an endomorphism of `TableExpression`s which adds a
572-- | A `where_` is an endomorphism of `TableExpression`s which adds a
763-- search condition to the `whereClause`.
573-- search condition to the `whereClause`.
764where_
574where_
765− :: Condition outer commons 'Ungrouped schemas params from -- ^ filtering condition
575+ :: Condition schema relations 'Ungrouped params -- ^ filtering condition
766− -> TableExpression outer commons grp schemas params from
576+ -> TableExpression schema params relations grouping
767− -> TableExpression outer commons grp schemas params from
577+ -> TableExpression schema params relations grouping
768where_ wh rels = rels {whereClause = wh : whereClause rels}
578where_ wh rels = rels {whereClause = wh : whereClause rels}
769
579
770−-- | A `groupBy` is a transformation of `TableExpression`s which switches
580+-- | A `group` is a transformation of `TableExpression`s which switches
771−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform
581+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform
772-- a "grand total" aggregation query.
582-- a "grand total" aggregation query.
773−groupBy
583+group
774 :: SListI bys
584 :: SListI bys
775− => NP (By from) bys -- ^ grouped columns
585+ => NP (By relations) bys -- ^ grouped columns
776− -> TableExpression outer commons 'Ungrouped schemas params from
586+ -> TableExpression schema params relations 'Ungrouped
777− -> TableExpression outer commons ('Grouped bys) schemas params from
587+ -> TableExpression schema params relations ('Grouped bys)
778−groupBy bys rels = TableExpression
588+group bys rels = TableExpression
779 { fromClause = fromClause rels
589 { fromClause = fromClause rels
780 , whereClause = whereClause rels
590 , whereClause = whereClause rels
781− , groupByClause = group bys
591+ , groupByClause = Group bys
782 , havingClause = Having []
592 , havingClause = Having []
783 , orderByClause = []
593 , orderByClause = []
784 , limitClause = limitClause rels
594 , limitClause = limitClause rels
@@ -788,31 +598,68 @@ groupBy bys rels = TableExpression
788-- | A `having` is an endomorphism of `TableExpression`s which adds a
598-- | A `having` is an endomorphism of `TableExpression`s which adds a
789-- search condition to the `havingClause`.
599-- search condition to the `havingClause`.
790having
600having
791− :: Condition outer commons ('Grouped bys) schemas params from -- ^ having condition
601+ :: Condition schema relations ('Grouped bys) params -- ^ having condition
792− -> TableExpression outer commons ('Grouped bys) schemas params from
602+ -> TableExpression schema params relations ('Grouped bys)
793− -> TableExpression outer commons ('Grouped bys) schemas params from
603+ -> TableExpression schema params relations ('Grouped bys)
794having hv rels = rels
604having hv rels = rels
795 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }
605 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }
796
606
797−instance OrderBy TableExpression where
607+-- | An `orderBy` is an endomorphism of `TableExpression`s which appends an
608+-- ordering to the right of the `orderByClause`.
609+orderBy
610+ :: [SortExpression schema relations grouping params] -- ^ sort expressions
611+ -> TableExpression schema params relations grouping
612+ -> TableExpression schema params relations grouping
798− orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}
613+orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}
799
614
800-- | A `limit` is an endomorphism of `TableExpression`s which adds to the
615-- | A `limit` is an endomorphism of `TableExpression`s which adds to the
801-- `limitClause`.
616-- `limitClause`.
802limit
617limit
803 :: Word64 -- ^ limit parameter
618 :: Word64 -- ^ limit parameter
804− -> TableExpression outer commons grp schemas params from
619+ -> TableExpression schema params relations grouping
805− -> TableExpression outer commons grp schemas params from
620+ -> TableExpression schema params relations grouping
806limit lim rels = rels {limitClause = lim : limitClause rels}
621limit lim rels = rels {limitClause = lim : limitClause rels}
807
622
808-- | An `offset` is an endomorphism of `TableExpression`s which adds to the
623-- | An `offset` is an endomorphism of `TableExpression`s which adds to the
809-- `offsetClause`.
624-- `offsetClause`.
810offset
625offset
811 :: Word64 -- ^ offset parameter
626 :: Word64 -- ^ offset parameter
812− -> TableExpression outer commons grp schemas params from
627+ -> TableExpression schema params relations grouping
813− -> TableExpression outer commons grp schemas params from
628+ -> TableExpression schema params relations grouping
814offset off rels = rels {offsetClause = off : offsetClause rels}
629offset off rels = rels {offsetClause = off : offsetClause rels}
815
630
631+{-----------------------------------------
632+JSON stuff
633+-----------------------------------------}
634+
635+type PGjson_each j =
636+ '[ j ::: '[ "key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson ] ]
637+
638+type PGjsonb_each j =
639+ '[ j ::: '[ "key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjsonb ] ]
640+
641+-- | Expands the outermost JSON object into a set of key/value pairs.
642+--
643+-- See also 'jsonEachAsComposite'.
644+jsonEach
645+ :: Aliased (Expression schema relations 'Ungrouped params) '(jt, nullity 'PGjson)
646+ -> TableExpression schema params (PGjson_each j) 'Ungrouped
647+jsonEach (As jexpr jname) = from . UnsafeFromClause
648+ $ renderExpression (jsonEachAsComposite jexpr)
649+ <+> "AS"
650+ <+> renderAlias jname
651+
652+-- | Expands the outermost JSON object into a set of key/value pairs.
653+--
654+-- See also 'jsonbEachAsComposite'.
655+jsonbEach
656+ :: Aliased (Expression schema relations 'Ungrouped params) '(jt, nullity 'PGjsonb)
657+ -> TableExpression schema params (PGjsonb_each j) 'Ungrouped
658+jsonbEach (As jexpr jname) = from . UnsafeFromClause
659+ $ renderExpression (jsonbEachAsComposite jexpr)
660+ <+> "AS"
661+ <+> renderAlias jname
662+
816{-----------------------------------------
663{-----------------------------------------
817FROM clauses
664FROM clauses
818-----------------------------------------}
665-----------------------------------------}
@@ -821,76 +668,61 @@ FROM clauses
821A `FromClause` can be a table name, or a derived table such
668A `FromClause` can be a table name, or a derived table such
822as a subquery, a @JOIN@ construct, or complex combinations of these.
669as a subquery, a @JOIN@ construct, or complex combinations of these.
823-}
670-}
824−newtype FromClause outer commons schemas params from
671+newtype FromClause schema params relations
825 = UnsafeFromClause { renderFromClause :: ByteString }
672 = UnsafeFromClause { renderFromClause :: ByteString }
826 deriving (GHC.Generic,Show,Eq,Ord,NFData)
673 deriving (GHC.Generic,Show,Eq,Ord,NFData)
827−instance RenderSQL (FromClause outer commons schemas params from) where
828− renderSQL = renderFromClause
829
674
830−-- | A real `table` is a table from the database.
675+-- | A real `table` is a table from the schema.
831table
676table
832− :: (Has sch schemas schema, Has tab schema ('Table table))
677+ :: Has tab schema ('Table table)
833− => Aliased (QualifiedAlias sch) (alias ::: tab)
678+ => Aliased Alias (alias ::: tab)
834− -> FromClause outer commons schemas params '[alias ::: TableToRow table]
679+ -> FromClause schema params '[alias ::: TableToRelation table]
835table (tab `As` alias) = UnsafeFromClause $
680table (tab `As` alias) = UnsafeFromClause $
836− renderSQL tab <+> "AS" <+> renderSQL alias
681+ renderAlias tab <+> "AS" <+> renderAlias alias
837
682
838-- | `subquery` derives a table from a `Query`.
683-- | `subquery` derives a table from a `Query`.
839subquery
684subquery
840− :: Aliased (Query outer commons schemas params) query
685+ :: Aliased (Query schema params) rel
841− -> FromClause outer commons schemas params '[query]
686+ -> FromClause schema params '[rel]
842−subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)
687+subquery = UnsafeFromClause . renderAliasedAs (parenthesized . renderQuery)
843
688
844-- | `view` derives a table from a `View`.
689-- | `view` derives a table from a `View`.
845view
690view
846− :: (Has sch schemas schema, Has vw schema ('View view))
691+ :: Has view schema ('View rel)
847− => Aliased (QualifiedAlias sch) (alias ::: vw)
692+ => Aliased Alias (alias ::: view)
848− -> FromClause outer commons schemas params '[alias ::: view]
693+ -> FromClause schema params '[alias ::: rel]
849view (vw `As` alias) = UnsafeFromClause $
694view (vw `As` alias) = UnsafeFromClause $
850− renderSQL vw <+> "AS" <+> renderSQL alias
695+ renderAlias vw <+> "AS" <+> renderAlias alias
851−
852−-- | `common` derives a table from a common table expression.
853−common
854− :: Has cte commons common
855− => Aliased Alias (alias ::: cte)
856− -> FromClause outer commons schemas params '[alias ::: common]
857−common (cte `As` alias) = UnsafeFromClause $
858− renderSQL cte <+> "AS" <+> renderSQL alias
859
696
860−instance Additional (FromClause outer commons schemas params) where
861− also right left = UnsafeFromClause $
862− renderSQL left <> ", " <> renderSQL right
863−
864−{- |
865−@left & crossJoin right@. For every possible combination of rows from
697+{- | @left & crossJoin right@. For every possible combination of rows from
866−@left@ and @right@ (i.e., a Cartesian product), the joined table will contain
698+ @left@ and @right@ (i.e., a Cartesian product), the joined table will contain
867−a row consisting of all columns in @left@ followed by all columns in @right@.
699+ a row consisting of all columns in @left@ followed by all columns in @right@.
868−If the tables have @n@ and @m@ rows respectively, the joined table will
700+ If the tables have @n@ and @m@ rows respectively, the joined table will
869−have @n * m@ rows.
701+ have @n * m@ rows.
870-}
702-}
871crossJoin
703crossJoin
872− :: FromClause outer commons schemas params right
704+ :: FromClause schema params right
873 -- ^ right
705 -- ^ right
874− -> FromClause outer commons schemas params left
706+ -> FromClause schema params left
875 -- ^ left
707 -- ^ left
876− -> FromClause outer commons schemas params (Join left right)
708+ -> FromClause schema params (Join left right)
877crossJoin right left = UnsafeFromClause $
709crossJoin right left = UnsafeFromClause $
878− renderSQL left <+> "CROSS JOIN" <+> renderSQL right
710+ renderFromClause left <+> "CROSS JOIN" <+> renderFromClause right
879
711
880{- | @left & innerJoin right on@. The joined table is filtered by
712{- | @left & innerJoin right on@. The joined table is filtered by
881the @on@ condition.
713the @on@ condition.
882-}
714-}
883innerJoin
715innerJoin
884− :: FromClause outer commons schemas params right
716+ :: FromClause schema params right
885 -- ^ right
717 -- ^ right
886− -> Condition outer commons 'Ungrouped schemas params (Join left right)
718+ -> Condition schema (Join left right) 'Ungrouped params
887 -- ^ @on@ condition
719 -- ^ @on@ condition
888− -> FromClause outer commons schemas params left
720+ -> FromClause schema params left
889 -- ^ left
721 -- ^ left
890− -> FromClause outer commons schemas params (Join left right)
722+ -> FromClause schema params (Join left right)
891innerJoin right on left = UnsafeFromClause $
723innerJoin right on left = UnsafeFromClause $
892− renderSQL left <+> "INNER JOIN" <+> renderSQL right
724+ renderFromClause left <+> "INNER JOIN" <+> renderFromClause right
893− <+> "ON" <+> renderSQL on
725+ <+> "ON" <+> renderExpression on
894
726
895{- | @left & leftOuterJoin right on@. First, an inner join is performed.
727{- | @left & leftOuterJoin right on@. First, an inner join is performed.
896 Then, for each row in @left@ that does not satisfy the @on@ condition with
728 Then, for each row in @left@ that does not satisfy the @on@ condition with
@@ -898,16 +730,16 @@ innerJoin right on left = UnsafeFromClause $
898 Thus, the joined table always has at least one row for each row in @left@.
730 Thus, the joined table always has at least one row for each row in @left@.
899-}
731-}
900leftOuterJoin
732leftOuterJoin
901− :: FromClause outer commons schemas params right
733+ :: FromClause schema params right
902 -- ^ right
734 -- ^ right
903− -> Condition outer commons 'Ungrouped schemas params (Join left right)
735+ -> Condition schema (Join left right) 'Ungrouped params
904 -- ^ @on@ condition
736 -- ^ @on@ condition
905− -> FromClause outer commons schemas params left
737+ -> FromClause schema params left
906 -- ^ left
738 -- ^ left
907− -> FromClause outer commons schemas params (Join left (NullifyFrom right))
739+ -> FromClause schema params (Join left (NullifyRelations right))
908leftOuterJoin right on left = UnsafeFromClause $
740leftOuterJoin right on left = UnsafeFromClause $
909− renderSQL left <+> "LEFT OUTER JOIN" <+> renderSQL right
741+ renderFromClause left <+> "LEFT OUTER JOIN" <+> renderFromClause right
910− <+> "ON" <+> renderSQL on
742+ <+> "ON" <+> renderExpression on
911
743
912{- | @left & rightOuterJoin right on@. First, an inner join is performed.
744{- | @left & rightOuterJoin right on@. First, an inner join is performed.
913 Then, for each row in @right@ that does not satisfy the @on@ condition with
745 Then, for each row in @right@ that does not satisfy the @on@ condition with
@@ -916,16 +748,16 @@ leftOuterJoin right on left = UnsafeFromClause $
916 have a row for each row in @right@.
748 have a row for each row in @right@.
917-}
749-}
918rightOuterJoin
750rightOuterJoin
919− :: FromClause outer commons schemas params right
751+ :: FromClause schema params right
920 -- ^ right
752 -- ^ right
921− -> Condition outer commons 'Ungrouped schemas params (Join left right)
753+ -> Condition schema (Join left right) 'Ungrouped params
922 -- ^ @on@ condition
754 -- ^ @on@ condition
923− -> FromClause outer commons schemas params left
755+ -> FromClause schema params left
924 -- ^ left
756 -- ^ left
925− -> FromClause outer commons schemas params (Join (NullifyFrom left) right)
757+ -> FromClause schema params (Join (NullifyRelations left) right)
926rightOuterJoin right on left = UnsafeFromClause $
758rightOuterJoin right on left = UnsafeFromClause $
927− renderSQL left <+> "RIGHT OUTER JOIN" <+> renderSQL right
759+ renderFromClause left <+> "RIGHT OUTER JOIN" <+> renderFromClause right
928− <+> "ON" <+> renderSQL on
760+ <+> "ON" <+> renderExpression on
929
761
930{- | @left & fullOuterJoin right on@. First, an inner join is performed.
762{- | @left & fullOuterJoin right on@. First, an inner join is performed.
931 Then, for each row in @left@ that does not satisfy the @on@ condition with
763 Then, for each row in @left@ that does not satisfy the @on@ condition with
@@ -935,56 +767,47 @@ rightOuterJoin right on left = UnsafeFromClause $
935 is added.
767 is added.
936-}
768-}
937fullOuterJoin
769fullOuterJoin
938− :: FromClause outer commons schemas params right
770+ :: FromClause schema params right
939 -- ^ right
771 -- ^ right
940− -> Condition outer commons 'Ungrouped schemas params (Join left right)
772+ -> Condition schema (Join left right) 'Ungrouped params
941 -- ^ @on@ condition
773 -- ^ @on@ condition
942− -> FromClause outer commons schemas params left
774+ -> FromClause schema params left
943 -- ^ left
775 -- ^ left
944− -> FromClause outer commons schemas params
776+ -> FromClause schema params
945− (Join (NullifyFrom left) (NullifyFrom right))
777+ (Join (NullifyRelations left) (NullifyRelations right))
946fullOuterJoin right on left = UnsafeFromClause $
778fullOuterJoin right on left = UnsafeFromClause $
947− renderSQL left <+> "FULL OUTER JOIN" <+> renderSQL right
779+ renderFromClause left <+> "FULL OUTER JOIN" <+> renderFromClause right
948− <+> "ON" <+> renderSQL on
780+ <+> "ON" <+> renderExpression on
949
781
950{-----------------------------------------
782{-----------------------------------------
951Grouping
783Grouping
952-----------------------------------------}
784-----------------------------------------}
953
785
954−-- | `By`s are used in `groupBy` to reference a list of columns which are then
786+-- | `By`s are used in `group` to reference a list of columns which are then
955-- used to group together those rows in a table that have the same values
787-- used to group together those rows in a table that have the same values
956-- in all the columns listed. @By \#col@ will reference an unambiguous
788-- in all the columns listed. @By \#col@ will reference an unambiguous
957-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table
789-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table
958-- qualified column @tab.col@.
790-- qualified column @tab.col@.
959data By
791data By
960− (from :: FromType)
792+ (relations :: RelationsType)
961 (by :: (Symbol,Symbol)) where
793 (by :: (Symbol,Symbol)) where
962− By1
794+ By
963− :: (HasUnique table from columns, Has column columns ty)
795+ :: (HasUnique relation relations columns, Has column columns ty)
964 => Alias column
796 => Alias column
965− -> By from '(table, column)
797+ -> By relations '(relation, column)
966 By2
798 By2
967− :: (Has table from columns, Has column columns ty)
799+ :: (Has relation relations columns, Has column columns ty)
968− => Alias table
969− -> Alias column
800+ => (Alias relation, Alias column)
970− -> By from '(table, column)
801+ -> By relations '(relation, column)
971−deriving instance Show (By from by)
802+deriving instance Show (By relations by)
972−deriving instance Eq (By from by)
803+deriving instance Eq (By relations by)
973−deriving instance Ord (By from by)
804+deriving instance Ord (By relations by)
974−instance RenderSQL (By from by) where
805+
975− renderSQL = \case
806+-- | Renders a `By`.
807+renderBy :: By relations by -> ByteString
808+renderBy = \case
976− By1 column -> renderSQL column
809+ By column -> renderAlias column
977− By2 rel column -> renderSQL rel <> "." <> renderSQL column
810+ By2 (rel, column) -> renderAlias rel <> "." <> renderAlias column
978−
979−instance (HasUnique rel rels cols, Has col cols ty, by ~ '(rel, col))
980− => IsLabel col (By rels by) where fromLabel = By1 fromLabel
981−instance (HasUnique rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])
982− => IsLabel col (NP (By rels) bys) where fromLabel = By1 fromLabel :* Nil
983−instance (Has rel rels cols, Has col cols ty, by ~ '(rel, col))
984− => IsQualified rel col (By rels by) where (!) = By2
985−instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])
986− => IsQualified rel col (NP (By rels) bys) where
987− rel ! col = By2 rel col :* Nil
988
811
989-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.
812-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.
990-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.
813-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.
@@ -992,107 +815,82 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])
992-- done on @NoGroups@ while all output `Expression`s must be aggregated
815-- done on @NoGroups@ while all output `Expression`s must be aggregated
993-- in @Group Nil@. In general, all output `Expression`s in the
816-- in @Group Nil@. In general, all output `Expression`s in the
994-- complement of @bys@ must be aggregated in @Group bys@.
817-- complement of @bys@ must be aggregated in @Group bys@.
995−newtype GroupByClause grp from = UnsafeGroupByClause
818+data GroupByClause relations grouping where
996− { renderGroupByClause :: ByteString }
997− deriving (GHC.Generic,Show,Eq,Ord,NFData)
998−instance RenderSQL (GroupByClause grp from) where
999− renderSQL = renderGroupByClause
1000−noGroups :: GroupByClause 'Ungrouped from
819+ NoGroups :: GroupByClause relations 'Ungrouped
1001−noGroups = UnsafeGroupByClause ""
820+ Group
1002−group
1003− :: SListI bys
821+ :: SListI bys
1004− => NP (By from) bys
822+ => NP (By relations) bys
1005− -> GroupByClause ('Grouped bys) from
823+ -> GroupByClause relations ('Grouped bys)
1006−group bys = UnsafeGroupByClause $ case bys of
824+
825+-- | Renders a `GroupByClause`.
826+renderGroupByClause :: GroupByClause relations grouping -> ByteString
827+renderGroupByClause = \case
828+ NoGroups -> ""
1007− Nil -> ""
829+ Group Nil -> ""
1008− bys' -> " GROUP BY" <+> renderCommaSeparated renderSQL bys'
830+ Group bys -> " GROUP BY" <+> renderCommaSeparated renderBy bys
1009
831
1010-- | A `HavingClause` is used to eliminate groups that are not of interest.
832-- | A `HavingClause` is used to eliminate groups that are not of interest.
1011-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`
833-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`
1012-- `TableExpression` must use `Having` whose conditions are combined with
834-- `TableExpression` must use `Having` whose conditions are combined with
1013-- `.&&`.
835-- `.&&`.
1014−data HavingClause outer commons grp schemas params from where
836+data HavingClause schema relations grouping params where
1015− NoHaving :: HavingClause outer commons 'Ungrouped schemas params from
837+ NoHaving :: HavingClause schema relations 'Ungrouped params
1016 Having
838 Having
1017− :: [Condition outer commons ('Grouped bys) schemas params from]
839+ :: [Condition schema relations ('Grouped bys) params]
1018− -> HavingClause outer commons ('Grouped bys) schemas params from
840+ -> HavingClause schema relations ('Grouped bys) params
1019−deriving instance Show (HavingClause outer commons grp schemas params from)
841+deriving instance Show (HavingClause schema relations grouping params)
1020−deriving instance Eq (HavingClause outer commons grp schemas params from)
842+deriving instance Eq (HavingClause schema relations grouping params)
1021−deriving instance Ord (HavingClause outer commons grp schemas params from)
843+deriving instance Ord (HavingClause schema relations grouping params)
1022
844
1023-- | Render a `HavingClause`.
845-- | Render a `HavingClause`.
1024−instance RenderSQL (HavingClause outer commons grp schemas params from) where
846+renderHavingClause :: HavingClause schema relations grouping params -> ByteString
1025− renderSQL = \case
847+renderHavingClause = \case
1026− NoHaving -> ""
848+ NoHaving -> ""
1027− Having [] -> ""
849+ Having [] -> ""
1028− Having conditions ->
850+ Having conditions ->
1029− " HAVING" <+> commaSeparated (renderSQL <$> conditions)
851+ " HAVING" <+> commaSeparated (renderExpression <$> conditions)
1030−
1031−-- | A `CommonTableExpression` is an auxiliary statement in a `with` clause.
1032−data CommonTableExpression statement
1033− (schemas :: SchemasType)
1034− (params :: [NullityType])
1035− (commons0 :: FromType)
1036− (commons1 :: FromType) where
1037− CommonTableExpression
1038− :: Aliased (statement commons schemas params) (cte ::: common)
1039− -> CommonTableExpression statement schemas params commons (cte ::: common ': commons)
1040−instance
1041− ( KnownSymbol cte
1042− , commons1 ~ (cte ::: common ': commons)
1043− ) => Aliasable cte
1044− (statement commons schemas params common)
1045− (CommonTableExpression statement schemas params commons commons1) where
1046− statement `as` cte = CommonTableExpression (statement `as` cte)
1047−instance
1048− ( KnownSymbol cte
1049− , commons1 ~ (cte ::: common ': commons)
1050− ) => Aliasable cte
1051− (statement commons schemas params common)
1052− (Path (CommonTableExpression statement schemas params) commons commons1) where
1053− statement `as` cte = csingleton (statement `as` cte)
1054−
1055−instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL
1056− (CommonTableExpression statement schemas params commons0 commons1) where
1057− renderSQL (CommonTableExpression (statement `As` cte)) =
1058− renderSQL cte <+> "AS" <+> parenthesized (renderSQL statement)
1059−
1060−-- | `with` provides a way to write auxiliary statements for use in a larger query.
1061−-- These statements, referred to as `CommonTableExpression`s, can be thought of as
1062−-- defining temporary tables that exist just for one query.
1063−class With statement where
1064− with
1065− :: Path (CommonTableExpression statement schemas params) commons0 commons1
1066− -- ^ common table expressions
1067− -> statement commons1 schemas params row
1068− -- ^ larger query
1069− -> statement commons0 schemas params row
1070−instance With (Query outer) where
1071− with Done query = query
1072− with ctes query = UnsafeQuery $
1073− "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL query
1074
852
1075−{- |
853+{-----------------------------------------
1076−>>> import Data.Monoid (Sum (..))
854+Sorting
1077−>>> import Data.Int (Int64)
855+-----------------------------------------}
1078−>>> :{
856+
1079− let
857+-- | `SortExpression`s are used by `sortBy` to optionally sort the results
1080− query :: Query_ schema () (Sum Int64)
858+-- of a `Query`. `Asc` or `Desc` set the sort direction of a `NotNull` result
1081− query = withRecursive
859+-- column to ascending or descending. Ascending order puts smaller values
1082− ( values_ ((1 & astype int) `as` #n)
860+-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,
1083− `unionAll`
861+-- descending order is determined with the `.>` operator. `AscNullsFirst`,
1084− select_ ((#n + 1) `as` #n)
862+-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to
1085− (from (common #t) & where_ (#n .< 100)) `as` #t )
863+-- determine whether nulls appear before or after non-null values in the sort
1086− ( select_ (fromNull 0 (sum_ (All #n)) `as` #getSum) (from (common #t) & groupBy Nil))
864+-- ordering of a `Null` result column.
1087− in printSQL query
865+data SortExpression schema relations grouping params where
1088−:}
866+ Asc
1089−WITH RECURSIVE "t" AS ((SELECT * FROM (VALUES ((1 :: int))) AS t ("n")) UNION ALL (SELECT ("n" + 1) AS "n" FROM "t" AS "t" WHERE ("n" < 100))) SELECT COALESCE(sum(ALL "n"), 0) AS "getSum" FROM "t" AS "t"
867+ :: Expression schema relations grouping params ('NotNull ty)
1090−-}
868+ -> SortExpression schema relations grouping params
1091−withRecursive
869+ Desc
1092− :: Aliased (Query outer (recursive ': commons) schemas params) recursive
870+ :: Expression schema relations grouping params ('NotNull ty)
1093− -> Query outer (recursive ': commons) schemas params row
871+ -> SortExpression schema relations grouping params
1094− -> Query outer commons schemas params row
872+ AscNullsFirst
1095−withRecursive (recursive `As` cte) query = UnsafeQuery $
873+ :: Expression schema relations grouping params ('Null ty)
1096− "WITH RECURSIVE" <+> renderSQL cte
874+ -> SortExpression schema relations grouping params
1097− <+> "AS" <+> parenthesized (renderSQL recursive)
875+ AscNullsLast
1098− <+> renderSQL query
876+ :: Expression schema relations grouping params ('Null ty)
877+ -> SortExpression schema relations grouping params
878+ DescNullsFirst
879+ :: Expression schema relations grouping params ('Null ty)
880+ -> SortExpression schema relations grouping params
881+ DescNullsLast
882+ :: Expression schema relations grouping params ('Null ty)
883+ -> SortExpression schema relations grouping params
884+deriving instance Show (SortExpression schema relations grouping params)
885+
886+-- | Render a `SortExpression`.
887+renderSortExpression :: SortExpression schema relations grouping params -> ByteString
888+renderSortExpression = \case
889+ Asc expression -> renderExpression expression <+> "ASC"
890+ Desc expression -> renderExpression expression <+> "DESC"
891+ AscNullsFirst expression -> renderExpression expression
892+ <+> "ASC NULLS FIRST"
893+ DescNullsFirst expression -> renderExpression expression
894+ <+> "DESC NULLS FIRST"
895+ AscNullsLast expression -> renderExpression expression <+> "ASC NULLS LAST"
896+ DescNullsLast expression -> renderExpression expression <+> "DESC NULLS LAST"
squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+13−66
@@ -9,48 +9,35 @@ Rendering helper functions.
9-}
9-}
10
10
11{-# LANGUAGE
11{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , FlexibleContexts
12+ FlexibleContexts
15− , LambdaCase
16 , MagicHash
13 , MagicHash
17 , OverloadedStrings
14 , OverloadedStrings
18 , PolyKinds
15 , PolyKinds
19 , RankNTypes
16 , RankNTypes
20 , ScopedTypeVariables
17 , ScopedTypeVariables
21− , TypeApplications
22#-}
18#-}
23
19
24module Squeal.PostgreSQL.Render
20module Squeal.PostgreSQL.Render
25 ( -- * Render
21 ( -- * Render
26− RenderSQL (..)
27− , printSQL
28− , escape
29− , parenthesized
22+ parenthesized
30− , bracketed
31 , (<+>)
23 , (<+>)
32 , commaSeparated
24 , commaSeparated
33 , doubleQuoted
25 , doubleQuoted
34− , singleQuotedText
35− , singleQuotedUtf8
36 , renderCommaSeparated
26 , renderCommaSeparated
37− , renderCommaSeparatedConstraint
38 , renderCommaSeparatedMaybe
27 , renderCommaSeparatedMaybe
39 , renderNat
28 , renderNat
40− , renderSymbol
29+ , RenderSQL (..)
30+ , printSQL
41 ) where
31 ) where
42
32
43−import Control.Monad.IO.Class (MonadIO (..))
33+import Control.Monad.Base
44import Data.ByteString (ByteString)
34import Data.ByteString (ByteString)
45−import Data.Maybe (catMaybes)
35+import Data.Maybe
46import Data.Monoid ((<>))
36import Data.Monoid ((<>))
47−import Data.Text (Text)
48import Generics.SOP
37import Generics.SOP
49import GHC.Exts
38import GHC.Exts
50−import GHC.TypeLits hiding (Text)
39+import GHC.TypeLits
51
40
52−import qualified Data.Text as Text
53−import qualified Data.Text.Encoding as Text
54import qualified Data.ByteString as ByteString
41import qualified Data.ByteString as ByteString
55import qualified Data.ByteString.Char8 as Char8
42import qualified Data.ByteString.Char8 as Char8
56
43
@@ -58,13 +45,8 @@ import qualified Data.ByteString.Char8 as Char8
58parenthesized :: ByteString -> ByteString
45parenthesized :: ByteString -> ByteString
59parenthesized str = "(" <> str <> ")"
46parenthesized str = "(" <> str <> ")"
60
47
61−-- | Square bracket a `ByteString`
62−bracketed :: ByteString -> ByteString
63−bracketed str = "[" <> str <> "]"
64−
65-- | Concatenate two `ByteString`s with a space between.
48-- | Concatenate two `ByteString`s with a space between.
66(<+>) :: ByteString -> ByteString -> ByteString
49(<+>) :: ByteString -> ByteString -> ByteString
67−infixr 7 <+>
68str1 <+> str2 = str1 <> " " <> str2
50str1 <+> str2 = str1 <> " " <> str2
69
51
70-- | Comma separate a list of `ByteString`s.
52-- | Comma separate a list of `ByteString`s.
@@ -75,15 +57,6 @@ commaSeparated = ByteString.intercalate ", "
75doubleQuoted :: ByteString -> ByteString
57doubleQuoted :: ByteString -> ByteString
76doubleQuoted str = "\"" <> str <> "\""
58doubleQuoted str = "\"" <> str <> "\""
77
59
78−-- | Add single quotes around a `Text` and escape single quotes within it.
79−singleQuotedText :: Text -> ByteString
80−singleQuotedText str =
81− "'" <> Text.encodeUtf8 (Text.replace "'" "''" str) <> "'"
82−
83−-- | Add single quotes around a `ByteString` and escape single quotes within it.
84−singleQuotedUtf8 :: ByteString -> ByteString
85−singleQuotedUtf8 = singleQuotedText . Text.decodeUtf8
86−
87-- | Comma separate the renderings of a heterogeneous list.
60-- | Comma separate the renderings of a heterogeneous list.
88renderCommaSeparated
61renderCommaSeparated
89 :: SListI xs
62 :: SListI xs
@@ -94,16 +67,6 @@ renderCommaSeparated render
94 . hcollapse
67 . hcollapse
95 . hmap (K . render)
68 . hmap (K . render)
96
69
97−-- | Comma separate the renderings of a heterogeneous list.
98−renderCommaSeparatedConstraint
99− :: forall c xs expression. (All c xs, SListI xs)
100− => (forall x. c x => expression x -> ByteString)
101− -> NP expression xs -> ByteString
102−renderCommaSeparatedConstraint render
103− = commaSeparated
104− . hcollapse
105− . hcmap (Proxy @c) (K . render)
106−
107-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping
70-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping
108-- `Nothing`s.
71-- `Nothing`s.
109renderCommaSeparatedMaybe
72renderCommaSeparatedMaybe
@@ -117,29 +80,13 @@ renderCommaSeparatedMaybe render
117 . hmap (K . render)
80 . hmap (K . render)
118
81
119-- | Render a promoted `Nat`.
82-- | Render a promoted `Nat`.
120−renderNat :: forall n. KnownNat n => ByteString
83+renderNat :: KnownNat n => proxy n -> ByteString
121−renderNat = fromString (show (natVal' (proxy# :: Proxy# n)))
84+renderNat (_ :: proxy n) = fromString (show (natVal' (proxy# :: Proxy# n)))
122−
123−-- | Render a promoted `Symbol`.
124−renderSymbol :: forall s. KnownSymbol s => ByteString
125−renderSymbol = fromString (symbolVal' (proxy# :: Proxy# s))
126
85
127-- | A class for rendering SQL
86-- | A class for rendering SQL
128−class RenderSQL sql where renderSQL :: sql -> ByteString
87+class RenderSQL sql where
88+ renderSQL :: sql -> ByteString
129
89
130-- | Print SQL.
90-- | Print SQL.
131−printSQL :: (RenderSQL sql, MonadIO io) => sql -> io ()
91+printSQL :: (RenderSQL sql, MonadBase IO io) => sql -> io ()
132−printSQL = liftIO . Char8.putStrLn . renderSQL
92+printSQL = liftBase . Char8.putStrLn . renderSQL
133−
134−-- | `escape` a character to prevent injection
135−escape :: Char -> String
136−escape = \case
137− '\NUL' -> "\\0"
138− '\'' -> "''"
139− '"' -> "\\\""
140− '\b' -> "\\b"
141− '\n' -> "\\n"
142− '\r' -> "\\r"
143− '\t' -> "\\t"
144− '\\' -> "\\\\"
145− c -> [c]
squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+611−314
@@ -1,15 +1,16 @@
1{-|
1{-|
2Module: Squeal.PostgreSQL.Schema
2Module: Squeal.PostgreSQL.Schema
3Description: Embedding of PostgreSQL type and alias system
3Description: Embedding of PostgreSQL type and alias system
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
8−`Squeal.PostgreSQL.Schema` provides a type-level DSL for kinds of Postgres types,
8+This module provides a type-level DSL for kinds of Postgres types,
9tables, schema, constraints, aliases, enumerated labels, and groupings.
9tables, schema, constraints, aliases, enumerated labels, and groupings.
10It also defines useful type families to operate on these. Finally,
10It also defines useful type families to operate on these. Finally,
11it defines an embedding of Haskell types into Postgres types.
11it defines an embedding of Haskell types into Postgres types.
12-}
12-}
13+{-# OPTIONS_GHC -fno-warn-unticked-promoted-constructors #-}
13{-# LANGUAGE
14{-# LANGUAGE
14 AllowAmbiguousTypes
15 AllowAmbiguousTypes
15 , ConstraintKinds
16 , ConstraintKinds
@@ -19,9 +20,7 @@ it defines an embedding of Haskell types into Postgres types.
19 , FlexibleInstances
20 , FlexibleInstances
20 , FunctionalDependencies
21 , FunctionalDependencies
21 , GADTs
22 , GADTs
22− , LambdaCase
23 , OverloadedStrings
23 , OverloadedStrings
24− , QuantifiedConstraints
25 , RankNTypes
24 , RankNTypes
26 , ScopedTypeVariables
25 , ScopedTypeVariables
27 , StandaloneDeriving
26 , StandaloneDeriving
@@ -34,85 +33,129 @@ it defines an embedding of Haskell types into Postgres types.
34#-}
33#-}
35
34
36module Squeal.PostgreSQL.Schema
35module Squeal.PostgreSQL.Schema
37− ( -- * Postgres Types
36+ ( -- * Types
38 PGType (..)
37 PGType (..)
38+ , HasOid (..)
39 , NullityType (..)
39 , NullityType (..)
40− , RowType
41− , FromType
42− -- * Schema Types
43 , ColumnType
40 , ColumnType
41+ -- * Tables
44 , ColumnsType
42 , ColumnsType
43+ , RelationType
44+ , NilRelation
45+ , RelationsType
45 , TableType
46 , TableType
47+ -- * Schema
46 , SchemumType (..)
48 , SchemumType (..)
47− , IndexType (..)
48− , FunctionType
49− , OperatorType (..)
50− , ReturnsType (..)
51 , SchemaType
49 , SchemaType
52− , SchemasType
53− , Public
54 -- * Constraints
50 -- * Constraints
55 , (:=>)
51 , (:=>)
56 , ColumnConstraint (..)
52 , ColumnConstraint (..)
57 , TableConstraint (..)
53 , TableConstraint (..)
58 , TableConstraints
54 , TableConstraints
55+ , NilTableConstraints
59 , Uniquely
56 , Uniquely
57+ -- * Aliases
58+ , (:::)
59+ , Alias (Alias)
60+ , renderAlias
61+ , renderAliases
62+ , Aliased (As)
63+ , renderAliasedAs
64+ , AliasesOf
65+ , ZipAliased (..)
66+ , Has
67+ , HasUnique
68+ , HasAll
69+ , IsLabel (..)
70+ , IsQualified (..)
60 -- * Enumerated Labels
71 -- * Enumerated Labels
61 , IsPGlabel (..)
72 , IsPGlabel (..)
62 , PGlabel (..)
73 , PGlabel (..)
63− -- * Data Definitions
74+ , renderLabel
75+ , renderLabels
76+ -- * Grouping
77+ , Grouping (..)
78+ , GroupedBy
79+ -- * Type Families
80+ , Join
81+ , With
64 , Create
82 , Create
65− , CreateIfNotExists
66− , CreateOrReplace
67 , Drop
83 , Drop
68− , DropSchemum
69− , DropIfExists
70− , DropSchemumIfExists
71 , Alter
84 , Alter
72− , AlterIfExists
73 , Rename
85 , Rename
74− , RenameIfExists
86+ , Elem
75− , ConstraintInvolves
87+ , In
76− , DropIfConstraintsInvolve
77− , IsNotElem
78− , AllUnique
79− -- * Type Classifications
80 , PGNum
88 , PGNum
81 , PGIntegral
89 , PGIntegral
82 , PGFloating
90 , PGFloating
83 , PGTypeOf
91 , PGTypeOf
84− , PGJsonType
92+ , PGarrayOf
85− , PGJsonKey
93+ , PGarray
94+ , PGtextArray
95+ , PGobjectpairs
96+ , SameTypes
86 , SamePGType
97 , SamePGType
87 , AllNotNull
98 , AllNotNull
88 , NotAllNull
99 , NotAllNull
89− -- * Nullifications
90 , NullifyType
100 , NullifyType
91− , NullifyRow
101+ , NullifyRelation
92− , NullifyFrom
102+ , NullifyRelations
93− -- * Table Conversions
103+ , ColumnsToRelation
94 , TableToColumns
104 , TableToColumns
95− , ColumnsToRow
105+ , TableToRelation
96− , TableToRow
106+ , ConstraintInvolves
107+ , DropIfConstraintsInvolve
108+ -- ** JSON support
109+ , PGjson_
110+ , PGjsonKey
111+ -- * Embedding
112+ , PG
113+ , EnumFrom
114+ , LabelsFrom
115+ , CompositeFrom
116+ , FieldNamesFrom
117+ , FieldTypesFrom
118+ , ConstructorsOf
119+ , ConstructorNameOf
120+ , ConstructorNamesOf
121+ , FieldsOf
122+ , FieldNameOf
123+ , FieldNamesOf
124+ , FieldTypeOf
125+ , FieldTypesOf
126+ , RecordCodeOf
127+ , MapMaybes (..)
128+ , Nulls
97 ) where
129 ) where
98
130
99−import Control.Category
131+import Control.DeepSeq
132+import Data.Aeson (Value)
133+import Data.ByteString (ByteString)
134+import Data.Int (Int16, Int32, Int64)
100import Data.Kind
135import Data.Kind
101import Data.Monoid hiding (All)
136import Data.Monoid hiding (All)
137+import Data.Scientific (Scientific)
138+import Data.String
139+import Data.Text (Text)
140+import Data.Time
141+import Data.Word (Word16, Word32, Word64)
102import Data.Type.Bool
142import Data.Type.Bool
143+import Data.UUID.Types (UUID)
103import Generics.SOP
144import Generics.SOP
145+import GHC.OverloadedLabels
104import GHC.TypeLits
146import GHC.TypeLits
105−import Prelude hiding (id, (.))
147+import Network.IP.Addr
106
148
107−import Squeal.PostgreSQL.Alias
149+import qualified Data.ByteString.Lazy as Lazy
108−import Squeal.PostgreSQL.List
150+import qualified Data.Text.Lazy as Lazy
109−import Squeal.PostgreSQL.Render
151+import qualified GHC.Generics as GHC
152+import qualified Generics.SOP.Type.Metadata as Type
110
153
111−-- $setup
112−-- >>> import Squeal.PostgreSQL
154+import Squeal.PostgreSQL.Render
113
155
114-- | `PGType` is the promoted datakind of PostgreSQL types.
156-- | `PGType` is the promoted datakind of PostgreSQL types.
115--
157--
158+-- >>> import Squeal.PostgreSQL.Schema
116-- >>> :kind 'PGbool
159-- >>> :kind 'PGbool
117-- 'PGbool :: PGType
160-- 'PGbool :: PGType
118data PGType
161data PGType
@@ -123,7 +166,6 @@ data PGType
123 | PGnumeric -- ^ arbitrary precision numeric type
166 | PGnumeric -- ^ arbitrary precision numeric type
124 | PGfloat4 -- ^ single precision floating-point number (4 bytes)
167 | PGfloat4 -- ^ single precision floating-point number (4 bytes)
125 | PGfloat8 -- ^ double precision floating-point number (8 bytes)
168 | PGfloat8 -- ^ double precision floating-point number (8 bytes)
126− | PGmoney -- ^ currency amount
127 | PGchar Nat -- ^ fixed-length character string
169 | PGchar Nat -- ^ fixed-length character string
128 | PGvarchar Nat -- ^ variable-length character string
170 | PGvarchar Nat -- ^ variable-length character string
129 | PGtext -- ^ variable-length character string
171 | PGtext -- ^ variable-length character string
@@ -138,16 +180,40 @@ data PGType
138 | PGinet -- ^ IPv4 or IPv6 host address
180 | PGinet -- ^ IPv4 or IPv6 host address
139 | PGjson -- ^ textual JSON data
181 | PGjson -- ^ textual JSON data
140 | PGjsonb -- ^ binary JSON data, decomposed
182 | PGjsonb -- ^ binary JSON data, decomposed
141− | PGvararray NullityType -- ^ variable length array
183+ | PGvararray PGType -- ^ variable length array
142− | PGfixarray [Nat] NullityType -- ^ fixed length array
184+ | PGfixarray Nat PGType -- ^ fixed length array
143− | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.
185+ | PGenum [Symbol]
144− | PGcomposite RowType -- ^ a composite type represents the structure of a row or record; it is essentially just a list of field names and their data types.
186+ | PGcomposite [(Symbol, PGType)]
145− | PGtsvector -- ^ A tsvector value is a sorted list of distinct lexemes, which are words that have been normalized to merge different variants of the same word.
146− | PGtsquery -- ^ A tsquery value stores lexemes that are to be searched for.
147− | PGoid -- Object identifiers (OIDs) are used internally by PostgreSQL as primary keys for various system tables.
148− | PGrange PGType -- ^ Range types are data types representing a range of values of some element type (called the range's subtype).
149 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types
187 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types
150
188
189+-- | The object identifier of a `PGType`.
190+--
191+-- >>> :set -XTypeApplications
192+-- >>> oid @'PGbool
193+-- 16
194+class HasOid (ty :: PGType) where oid :: Word32
195+instance HasOid 'PGbool where oid = 16
196+instance HasOid 'PGint2 where oid = 21
197+instance HasOid 'PGint4 where oid = 23
198+instance HasOid 'PGint8 where oid = 20
199+instance HasOid 'PGnumeric where oid = 1700
200+instance HasOid 'PGfloat4 where oid = 700
201+instance HasOid 'PGfloat8 where oid = 701
202+instance HasOid ('PGchar n) where oid = 18
203+instance HasOid ('PGvarchar n) where oid = 1043
204+instance HasOid 'PGtext where oid = 25
205+instance HasOid 'PGbytea where oid = 17
206+instance HasOid 'PGtimestamp where oid = 1114
207+instance HasOid 'PGtimestamptz where oid = 1184
208+instance HasOid 'PGdate where oid = 1082
209+instance HasOid 'PGtime where oid = 1083
210+instance HasOid 'PGtimetz where oid = 1266
211+instance HasOid 'PGinterval where oid = 1186
212+instance HasOid 'PGuuid where oid = 2950
213+instance HasOid 'PGinet where oid = 869
214+instance HasOid 'PGjson where oid = 114
215+instance HasOid 'PGjsonb where oid = 3802
216+
151-- | `NullityType` encodes the potential presence or definite absence of a
217-- | `NullityType` encodes the potential presence or definite absence of a
152-- @NULL@ allowing operations which are sensitive to such to be well typed.
218-- @NULL@ allowing operations which are sensitive to such to be well typed.
153--
219--
@@ -166,6 +232,11 @@ data NullityType
166type (:=>) constraint ty = '(constraint,ty)
232type (:=>) constraint ty = '(constraint,ty)
167infixr 7 :=>
233infixr 7 :=>
168
234
235+-- | The alias operator `:::` is like a promoted version of `As`,
236+-- a type level pair between an alias and some type.
237+type (:::) (alias :: Symbol) ty = '(alias,ty)
238+infixr 6 :::
239+
169-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.
240-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.
170-- A column can be assigned a default value.
241-- A column can be assigned a default value.
171-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also
242-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also
@@ -207,14 +278,11 @@ data TableConstraint
207 | PrimaryKey [Symbol]
278 | PrimaryKey [Symbol]
208 | ForeignKey [Symbol] Symbol [Symbol]
279 | ForeignKey [Symbol] Symbol [Symbol]
209
280
210−{- | A `TableConstraints` is a row of `TableConstraint`s.
281+-- | A `TableConstraints` is a row of `TableConstraint`s.
211−
212−>>> :{
213−type family UsersConstraints :: TableConstraints where
214− UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]
215−:}
216−-}
217type TableConstraints = [(Symbol,TableConstraint)]
282type TableConstraints = [(Symbol,TableConstraint)]
283+-- | A monokinded empty `TableConstraints`.
284+type family NilTableConstraints :: TableConstraints where
285+ NilTableConstraints = '[]
218
286
219-- | A `ForeignKey` must reference columns that either are
287-- | A `ForeignKey` must reference columns that either are
220-- a `PrimaryKey` or form a `Unique` constraint.
288-- a `PrimaryKey` or form a `Unique` constraint.
@@ -238,64 +306,265 @@ type family Uniquely
238-- :}
306-- :}
239type TableType = (TableConstraints,ColumnsType)
307type TableType = (TableConstraints,ColumnsType)
240
308
241−{- | A `RowType` is a row of `NullityType`. They correspond to Haskell
309+-- | `RelationType` is a row of `NullityType`
242−record types by means of `Squeal.PostgreSQL.Binary.RowPG` and are used in many places.
310+--
243−
244−>>> :{
311+-- >>> :{
245−type family PersonRow :: RowType where
312+-- type family PersonRelation :: RelationType where
246− PersonRow =
313+-- PersonRelation =
247− '[ "name" ::: 'NotNull 'PGtext
314+-- '[ "name" ::: 'NotNull 'PGtext
248− , "age" ::: 'NotNull 'PGint4
315+-- , "age" ::: 'NotNull 'PGint4
249− , "dateOfBirth" ::: 'Null 'PGdate
316+-- , "dateOfBirth" ::: 'Null 'PGdate
250− ]
317+-- ]
251−:}
318+-- :}
252−-}
253−type RowType = [(Symbol,NullityType)]
319+type RelationType = [(Symbol,NullityType)]
320+-- | A monokinded empty `RelationType`.
321+type family NilRelation :: RelationType where NilRelation = '[]
254
322
255−{- | `FromType` is a row of `RowType`s. It can be thought of as
323+-- | `RelationsType` is a row of `RelationType`s, thought of as a product.
256−a product, or horizontal gluing and is used in `Squeal.PostgreSQL.Query.FromClause`s
324+type RelationsType = [(Symbol,RelationType)]
257−and `Squeal.PostgreSQL.Query.TableExpression`s.
325+
258−-}
259−type FromType = [(Symbol,RowType)]
260−
261−-- | `ColumnsToRow` removes column constraints.
326+-- | `ColumnsToRelation` removes column constraints.
262−type family ColumnsToRow (columns :: ColumnsType) :: RowType where
327+type family ColumnsToRelation (columns :: ColumnsType) :: RelationType where
263− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': column5 ::: _ :=> ty5 ': columns) =
328+ ColumnsToRelation '[] = '[]
264− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': ColumnsToRow columns
329+ ColumnsToRelation (column ::: constraint :=> ty ': columns) =
265− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': columns) =
330+ column ::: ty ': ColumnsToRelation columns
266− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': ColumnsToRow columns
267− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': columns) =
268− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': ColumnsToRow columns
269− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': columns) =
270− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': ColumnsToRow columns
271− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': columns) =
272− column ::: ty ': column1 ::: ty1 ': ColumnsToRow columns
273− ColumnsToRow (column ::: _ :=> ty ': columns) =
274− column ::: ty ': ColumnsToRow columns
275− ColumnsToRow '[] = '[]
276
331
277-- | `TableToColumns` removes table constraints.
332-- | `TableToColumns` removes table constraints.
278type family TableToColumns (table :: TableType) :: ColumnsType where
333type family TableToColumns (table :: TableType) :: ColumnsType where
279 TableToColumns (constraints :=> columns) = columns
334 TableToColumns (constraints :=> columns) = columns
280
335
281−-- | Convert a table to a row type.
336+-- | Convert a table to a relation.
282−type family TableToRow (table :: TableType) :: RowType where
337+type family TableToRelation (table :: TableType) :: RelationType where
283− TableToRow tab = ColumnsToRow (TableToColumns tab)
338+ TableToRelation tab = ColumnsToRelation (TableToColumns tab)
284
339
285−-- | Numeric Postgres types.
340+-- | `Grouping` is an auxiliary namespace, created by
286−type PGNum =
341+-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used
287− '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]
342+-- for typesafe aggregation
343+data Grouping
344+ = Ungrouped -- ^ no aggregation permitted
345+ | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped
288
346
289−-- | Floating Postgres types.
347+{- | A `GroupedBy` constraint indicates that a table qualified column is
348+a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,
349+may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.
350+-}
351+class (KnownSymbol relation, KnownSymbol column)
352+ => GroupedBy relation column bys where
353+instance {-# OVERLAPPING #-} (KnownSymbol relation, KnownSymbol column)
354+ => GroupedBy relation column ('(table,column) ': bys)
355+instance {-# OVERLAPPABLE #-}
356+ ( KnownSymbol relation
357+ , KnownSymbol column
358+ , GroupedBy relation column bys
359+ ) => GroupedBy relation column (tabcol ': bys)
360+
361+-- | `Alias`es are proxies for a type level string or `Symbol`
362+-- and have an `IsLabel` instance so that with @-XOverloadedLabels@
363+--
364+-- >>> :set -XOverloadedLabels
365+-- >>> #foobar :: Alias "foobar"
366+-- Alias
367+data Alias (alias :: Symbol) = Alias
368+ deriving (Eq,GHC.Generic,Ord,Show,NFData)
369+instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where
370+ fromLabel = Alias
371+instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where
372+ fromLabel = fromLabel :* Nil
373+instance KnownSymbol alias => RenderSQL (Alias alias) where renderSQL = renderAlias
374+
375+-- | >>> renderAlias #jimbob
376+-- "\"jimbob\""
377+renderAlias :: KnownSymbol alias => Alias alias -> ByteString
378+renderAlias = doubleQuoted . fromString . symbolVal
379+
380+-- | >>> import Generics.SOP (NP(..))
381+-- >>> renderAliases (#jimbob :* #kandi :* Nil)
382+-- ["\"jimbob\"","\"kandi\""]
383+renderAliases
384+ :: All KnownSymbol aliases => NP Alias aliases -> [ByteString]
385+renderAliases = hcollapse
386+ . hcmap (Proxy @KnownSymbol) (K . renderAlias)
387+
388+-- | The `As` operator is used to name an expression. `As` is like a demoted
389+-- version of `:::`.
390+--
391+-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)
392+-- As (Just "hello") Alias
393+data Aliased expression aliased where
394+ As
395+ :: KnownSymbol alias
396+ => expression ty
397+ -> Alias alias
398+ -> Aliased expression (alias ::: ty)
399+deriving instance Show (expression ty)
400+ => Show (Aliased expression (alias ::: ty))
401+deriving instance Eq (expression ty)
402+ => Eq (Aliased expression (alias ::: ty))
403+deriving instance Ord (expression ty)
404+ => Ord (Aliased expression (alias ::: ty))
405+instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)
406+ => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where
407+ fromLabel = fromLabel @alias2 `As` fromLabel @alias1
408+
409+-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")
410+-- >>> renderAliasedAs renderMaybe (Just (3::Int) `As` #an_int)
411+-- "Just AS \"an_int\""
412+renderAliasedAs
413+ :: (forall ty. expression ty -> ByteString)
414+ -> Aliased expression aliased
415+ -> ByteString
416+renderAliasedAs render (expression `As` alias) =
417+ render expression <> " AS " <> renderAlias alias
418+
419+-- | `AliasesOf` retains the AliasesOf in a row.
420+type family AliasesOf aliaseds where
421+ AliasesOf '[] = '[]
422+ AliasesOf (alias ::: ty ': tys) = alias ': AliasesOf tys
423+
424+-- | The `ZipAliased` class provides a type family for zipping
425+-- `Symbol` lists together with arbitrary lists of the same size,
426+-- with an associated type family `ZipAs`, together with
427+-- a method `zipAs` for zipping heterogeneous lists of `Alias`es
428+-- together with a heterogeneous list of expressions into
429+-- a heterogeneous list of `Aliased` expressions.
430+class
431+ ( SListI (ZipAs ns xs)
432+ , All KnownSymbol ns
433+ ) => ZipAliased ns xs where
434+
435+ type family ZipAs
436+ (ns :: [Symbol]) (xs :: [k]) = (zs :: [(Symbol,k)]) | zs -> ns xs
437+
438+ zipAs
439+ :: NP Alias ns
440+ -> NP expr xs
441+ -> NP (Aliased expr) (ZipAs ns xs)
442+
443+instance ZipAliased '[] '[] where
444+ type ZipAs '[] '[] = '[]
445+ zipAs Nil Nil = Nil
446+
447+instance
448+ ( KnownSymbol n
449+ , ZipAliased ns xs
450+ ) => ZipAliased (n ': ns) (x ': xs) where
451+ type ZipAs (n ': ns) (x ': xs) = '(n,x) ': ZipAs ns xs
452+ zipAs (n :* ns) (x :* xs) = x `As` n :* zipAs ns xs
453+
454+-- | @HasUnique alias fields field@ is a constraint that proves that
455+-- @fields@ is a singleton of @alias ::: field@.
456+type HasUnique alias fields field = fields ~ '[alias ::: field]
457+
458+-- | @Has alias fields field@ is a constraint that proves that
459+-- @fields@ has a field of @alias ::: field@, inferring @field@
460+-- from @alias@ and @fields@.
461+class KnownSymbol alias =>
462+ Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)
463+ | alias fields -> field where
464+instance {-# OVERLAPPING #-} KnownSymbol alias
465+ => Has alias (alias ::: field ': fields) field
466+instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)
467+ => Has alias (field' ': fields) field
468+
469+-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer
470+-- a list of @subfields@.
471+class
472+ ( All KnownSymbol aliases
473+ ) => HasAll
474+ (aliases :: [Symbol])
475+ (fields :: [(Symbol,kind)])
476+ (subfields :: [(Symbol,kind)])
477+ | aliases fields -> subfields where
478+instance {-# OVERLAPPING #-} HasAll '[] fields '[]
479+instance {-# OVERLAPPABLE #-}
480+ (Has alias fields field, HasAll aliases fields subfields)
481+ => HasAll (alias ': aliases) fields (alias ::: field ': subfields)
482+
483+-- | Analagous to `IsLabel`, the constraint
484+-- `IsQualified` defines `!` for a column alias qualified
485+-- by a table alias.
486+class IsQualified table column expression where
487+ (!) :: Alias table -> Alias column -> expression
488+ infixl 9 !
489+instance IsQualified table column (Alias table, Alias column) where (!) = (,)
490+
491+-- | @Elem@ is a promoted `Data.List.elem`.
492+type family Elem x xs where
493+ Elem x '[] = 'False
494+ Elem x (x ': xs) = 'True
495+ Elem x (_ ': xs) = Elem x xs
496+
497+-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.
498+type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True
499+
500+-- | `PGNum` is a constraint on `PGType` whose
501+-- `Squeal.PostgreSQL.Expression.Expression`s have a `Num` constraint.
502+type PGNum ty =
503+ In ty '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]
504+
505+-- | `PGFloating` is a constraint on `PGType` whose
506+-- `Squeal.PostgreSQL.Expression.Expression`s
507+-- have `Fractional` and `Floating` constraints.
290−type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]
508+type PGFloating ty = In ty '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]
291−
509+
292−-- | Integral Postgres types.
510+-- | `PGIntegral` is a constraint on `PGType` whose
511+-- `Squeal.PostgreSQL.Expression.Expression`s
512+-- have `Squeal.PostgreSQL.Expression.div_` and
513+-- `Squeal.PostgreSQL.Expression.mod_` functions.
293−type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]
514+type PGIntegral ty = In ty '[ 'PGint2, 'PGint4, 'PGint8]
515+
516+-- | Error message helper for displaying unavailable\/unknown\/placeholder type
517+-- variables whose kind is known.
518+type Placeholder k = 'Text "(_::" :<>: 'ShowType k :<>: 'Text ")"
519+
520+type ErrArrayOf arr ty = arr :<>: 'Text " " :<>: ty
521+type ErrPGfixarrayOf t = ErrArrayOf ('ShowType 'PGfixarray :<>: 'Text " " :<>: Placeholder Nat) t
522+type ErrPGvararrayOf t = ErrArrayOf ('ShowType 'PGvararray) t
523+
524+-- | Ensure a type is a valid array type.
525+type family PGarray name arr :: Constraint where
526+ PGarray name ('PGvararray x) = ()
527+ PGarray name ('PGfixarray n x) = ()
528+ PGarray name val = TypeError
529+ ('Text name :<>: 'Text ": Unsatisfied PGarray constraint. Expected either: "
530+ :$$: 'Text " • " :<>: ErrPGvararrayOf (Placeholder PGType)
531+ :$$: 'Text " • " :<>: ErrPGfixarrayOf (Placeholder PGType)
532+ :$$: 'Text "But got: " :<>: 'ShowType val)
533+
534+-- | Ensure a type is a valid array type with a specific element type.
535+type family PGarrayOf name arr ty :: Constraint where
536+ PGarrayOf name ('PGvararray x) ty = x ~ ty
537+ PGarrayOf name ('PGfixarray n x) ty = x ~ ty
538+ PGarrayOf name val ty = TypeError
539+ ( 'Text name :<>: 'Text "Unsatisfied PGarrayOf constraint. Expected either: "
540+ :$$: 'Text " • " :<>: ErrPGvararrayOf ( 'ShowType ty )
541+ :$$: 'Text " • " :<>: ErrPGfixarrayOf ( 'ShowType ty )
542+ :$$: 'Text "But got: " :<>: 'ShowType val)
543+
544+-- | Ensure a type is a valid array type whose elements are text.
545+type PGtextArray name arr = PGarrayOf name arr 'PGtext
546+
547+-- | Ensure a list of arguments is an alternating list of text and value pairs.
548+type family PGobjectpairs name x :: Constraint where
549+ PGobjectpairs name ('NotNull 'PGtext : arg : xs) = PGobjectpairs name xs
550+ PGobjectpairs name '[] = ()
551+ PGobjectpairs name (x:xs) = TypeError
552+ ( 'Text name :<>: 'Text ": Incorrect argument list:"
553+ :$$: 'Text "Expected alternating list of keys and values."
554+ :$$: 'Text "But got " :<>: 'ShowType (x:xs))
294
555
295-- | `PGTypeOf` forgets about @NULL@ and any column constraints.
556-- | `PGTypeOf` forgets about @NULL@ and any column constraints.
296type family PGTypeOf (ty :: NullityType) :: PGType where
557type family PGTypeOf (ty :: NullityType) :: PGType where
297 PGTypeOf (nullity pg) = pg
558 PGTypeOf (nullity pg) = pg
298
559
560+-- | `SameTypes` is a constraint that proves two `ColumnsType`s have the same
561+-- length and the same `ColumnType`s.
562+type family SameTypes (columns0 :: ColumnsType) (columns1 :: ColumnsType)
563+ :: Constraint where
564+ SameTypes '[] '[] = ()
565+ SameTypes (column0 ::: def0 :=> ty0 ': columns0) (column1 ::: def1 :=> ty1 ': columns1)
566+ = (ty0 ~ ty1, SameTypes columns0 columns1)
567+
299-- | Equality constraint on the underlying `PGType` of two columns.
568-- | Equality constraint on the underlying `PGType` of two columns.
300class SamePGType
569class SamePGType
301 (ty0 :: (Symbol,ColumnType)) (ty1 :: (Symbol,ColumnType)) where
570 (ty0 :: (Symbol,ColumnType)) (ty1 :: (Symbol,ColumnType)) where
@@ -305,63 +574,39 @@ instance ty0 ~ ty1 => SamePGType
305
574
306-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.
575-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.
307type family AllNotNull (columns :: ColumnsType) :: Constraint where
576type family AllNotNull (columns :: ColumnsType) :: Constraint where
308− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
309− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
310− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
311− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
312− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
313− AllNotNull (_ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns
314 AllNotNull '[] = ()
577 AllNotNull '[] = ()
578+ AllNotNull (column ::: def :=> 'NotNull ty ': columns) = AllNotNull columns
315
579
316-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some
580-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some
317-- @NOT NULL@.
581-- @NOT NULL@.
318type family NotAllNull (columns :: ColumnsType) :: Constraint where
582type family NotAllNull (columns :: ColumnsType) :: Constraint where
319− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
583+ NotAllNull (column ::: def :=> 'NotNull ty ': columns) = ()
320− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
321− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
322− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
323− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
324− NotAllNull (_ ::: _ :=> 'NotNull _ ': _) = ()
325− NotAllNull (_ ::: _ :=> 'Null _ ': columns) = NotAllNull columns
584+ NotAllNull (column ::: def :=> 'Null ty ': columns) = NotAllNull columns
326−
585+
327−-- | `NullifyType` is an idempotent that nullifies a `NullityType`.
586+-- | `NullifyType` is an idempotent that nullifies a `ColumnType`.
328type family NullifyType (ty :: NullityType) :: NullityType where
587type family NullifyType (ty :: NullityType) :: NullityType where
329 NullifyType ('Null ty) = 'Null ty
588 NullifyType ('Null ty) = 'Null ty
330 NullifyType ('NotNull ty) = 'Null ty
589 NullifyType ('NotNull ty) = 'Null ty
331
590
332−-- | `NullifyRow` is an idempotent that nullifies a `RowType`.
591+-- | `NullifyRelation` is an idempotent that nullifies a `ColumnsType`.
333−type family NullifyRow (columns :: RowType) :: RowType where
592+type family NullifyRelation (columns :: RelationType) :: RelationType where
334− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': columns) =
593+ NullifyRelation '[] = '[]
335− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': column5 ::: NullifyType ty5 ': NullifyRow columns
594+ NullifyRelation (column ::: ty ': columns) =
336− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': columns) =
595+ column ::: NullifyType ty ': NullifyRelation columns
337− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': NullifyRow columns
596+
338− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': columns) =
339− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': NullifyRow columns
340− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': columns) =
341− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': NullifyRow columns
342− NullifyRow (column ::: ty ': column1 ::: ty1 ': columns) =
343− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': NullifyRow columns
344− NullifyRow (column ::: ty ': columns) =
345− column ::: NullifyType ty ': NullifyRow columns
346− NullifyRow '[] = '[]
347−
348−-- | `NullifyFrom` is an idempotent that nullifies a `FromType`
597+-- | `NullifyRelations` is an idempotent that nullifies a `RelationsType`
349-- used to nullify the left or right hand side of an outer join
598-- used to nullify the left or right hand side of an outer join
350-- in a `Squeal.PostgreSQL.Query.FromClause`.
599-- in a `Squeal.PostgreSQL.Query.FromClause`.
351−type family NullifyFrom (tables :: FromType) :: FromType where
600+type family NullifyRelations (tables :: RelationsType) :: RelationsType where
352− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': table5 ::: columns5 ': tables) =
601+ NullifyRelations '[] = '[]
353− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns5 ': table5 ::: NullifyRow columns4 ': NullifyFrom tables
602+ NullifyRelations (table ::: columns ': tables) =
354− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': tables) =
603+ table ::: NullifyRelation columns ': NullifyRelations tables
355− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns4 ': NullifyFrom tables
604+
356− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': tables) =
605+-- | `Join` is simply promoted `++` and is used in @JOIN@s in
357− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': NullifyFrom tables
606+-- `Squeal.PostgreSQL.Query.FromClause`s.
358− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': tables) =
607+type family Join xs ys where
359− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': NullifyFrom tables
608+ Join '[] ys = ys
360− NullifyFrom (table ::: columns ': table1 ::: columns1 ': tables) =
609+ Join (x ': xs) ys = x ': Join xs ys
361− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': NullifyFrom tables
362− NullifyFrom (table ::: columns ': tables) =
363− table ::: NullifyRow columns ': NullifyFrom tables
364− NullifyFrom '[] = '[]
365
610
366-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in
611-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in
367-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@
612-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@
@@ -371,100 +616,62 @@ type family Create alias x xs where
371 Create alias x (alias ::: y ': xs) = TypeError
616 Create alias x (alias ::: y ': xs) = TypeError
372 ('Text "Create: alias "
617 ('Text "Create: alias "
373 ':<>: 'ShowType alias
618 ':<>: 'ShowType alias
374− ':<>: 'Text "already exists")
619+ ':<>: 'Text "already in use")
375 Create alias y (x ': xs) = x ': Create alias y xs
620 Create alias y (x ': xs) = x ': Create alias y xs
376
621
377−type family CreateIfNotExists alias x xs where
378− CreateIfNotExists alias x '[] = '[alias ::: x]
379− CreateIfNotExists alias x (alias ::: y ': xs) = alias ::: y ': xs
380− CreateIfNotExists alias y (x ': xs) = x ': CreateIfNotExists alias y xs
381−
382−type family CreateOrReplace alias x xs where
383− CreateOrReplace alias x '[] = '[alias ::: x]
384− CreateOrReplace alias x (alias ::: x ': xs) = alias ::: x ': xs
385− CreateOrReplace alias x (alias ::: y ': xs) = TypeError
386− ('Text "CreateOrReplace: expected type "
387− ':<>: 'ShowType x
388− ':<>: 'Text " but alias "
389− ':<>: 'ShowType alias
390− ':<>: 'Text " has type "
391− ':<>: 'ShowType y)
392− CreateOrReplace alias y (x ': xs) = x ': CreateOrReplace alias y xs
393−
394-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@
622-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@
395-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements
623-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements
396-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.
624-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.
397type family Drop alias xs where
625type family Drop alias xs where
398− Drop alias '[] = TypeError
399− ('Text "Drop: alias "
400− ':<>: 'ShowType alias
401− ':<>: 'Text " does not exist" )
402− Drop alias (alias ::: x ': xs) = xs
626+ Drop alias ((alias ::: x) ': xs) = xs
403 Drop alias (x ': xs) = x ': Drop alias xs
627 Drop alias (x ': xs) = x ': Drop alias xs
404
628
405−type family DropSchemum alias sch xs where
406− DropSchemum alias sch '[] = TypeError
407− ('Text "DropSchemum: alias "
408− ':<>: 'ShowType alias
409− ':<>: 'Text " does not exist" )
410− DropSchemum alias sch (alias ::: sch x ': xs) = xs
411− DropSchemum alias sch0 (alias ::: sch1 x ': xs) = TypeError
412− ('Text "DropSchemum: expected schemum "
413− ':<>: 'ShowType sch0
414− ':<>: 'Text " but alias "
415− ':<>: 'ShowType alias
416− ':<>: 'Text " has schemum "
417− ':<>: 'ShowType sch1)
418− DropSchemum alias sch (x ': xs) = x ': DropSchemum alias sch xs
419−
420−type family DropIfExists alias xs where
421− DropIfExists alias '[] = '[]
422− DropIfExists alias (alias ::: x ': xs) = xs
423− DropIfExists alias (x ': xs) = x ': DropIfExists alias xs
424−
425−type family DropSchemumIfExists alias sch xs where
426− DropSchemumIfExists alias sch '[] = '[]
427− DropSchemumIfExists alias sch (alias ::: sch x ': xs) = xs
428− DropSchemumIfExists alias sch0 (alias ::: sch1 x ': xs) = TypeError
429− ('Text "DropSchemumIfExists: expected schemum "
430− ':<>: 'ShowType sch1
431− ':<>: 'Text " but alias "
432− ':<>: 'ShowType alias
433− ':<>: 'Text " has schemum "
434− ':<>: 'ShowType sch0)
435− DropSchemumIfExists alias sch (x ': xs) = x ': DropSchemumIfExists alias sch xs
436−
437-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@
629-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@
438−-- with the type @x@ and is used in `Squeal.PostgreSQL.Definition.alterTable`
630+-- with the type `x` and is used in `Squeal.PostgreSQL.Definition.alterTable`
439-- and `Squeal.PostgreSQL.Definition.alterColumn`.
631-- and `Squeal.PostgreSQL.Definition.alterColumn`.
440type family Alter alias x xs where
632type family Alter alias x xs where
441− Alter alias x '[] = TypeError
442− ('Text "Alter: alias "
443− ':<>: 'ShowType alias
444− ':<>: 'Text " does not exist" )
445 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
633 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
446 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs
634 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs
447
635
448−type family AlterIfExists alias x xs where
636+-- type family AddConstraint constraint ty where
449− AlterIfExists alias x '[] = '[]
637+-- AddConstraint constraint (constraints :=> ty)
450− AlterIfExists alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
638+-- = AsSet (constraint ': constraints) :=> ty
451− AlterIfExists alias x1 (x0 ': xs) = x0 ': AlterIfExists alias x1 xs
639+
640+-- type family DeleteFromList (e :: elem) (list :: [elem]) where
641+-- DeleteFromList elem '[] = '[]
642+-- DeleteFromList elem (x ': xs) =
643+-- If (Cmp elem x == 'EQ) xs (x ': DeleteFromList elem xs)
644+
645+-- type family DropConstraint constraint ty where
646+-- DropConstraint constraint (constraints :=> ty)
647+-- = (AsSet (DeleteFromList constraint constraints)) :=> ty
452
648
453-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@
649-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@
454-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and
650-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and
455-- `Squeal.PostgreSQL.Definition.renameColumn`.
651-- `Squeal.PostgreSQL.Definition.renameColumn`.
456type family Rename alias0 alias1 xs where
652type family Rename alias0 alias1 xs where
457− Rename alias0 alias1 '[] = TypeError
458− ('Text "Rename: alias "
459− ':<>: 'ShowType alias0
460− ':<>: 'Text " does not exist" )
461 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
653 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
462 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs
654 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs
463
655
464−type family RenameIfExists alias0 alias1 xs where
656+-- | `MapMaybes` is used in the binary instances of composite types.
465− RenameIfExists alias x '[] = '[]
657+class MapMaybes xs where
466− RenameIfExists alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
658+ type family Maybes (xs :: [Type]) = (mxs :: [Type]) | mxs -> xs
467− RenameIfExists alias0 alias1 (x ': xs) = x ': RenameIfExists alias0 alias1 xs
659+ maybes :: NP Maybe xs -> NP I (Maybes xs)
660+ unMaybes :: NP I (Maybes xs) -> NP Maybe xs
661+instance MapMaybes '[] where
662+ type Maybes '[] = '[]
663+ maybes Nil = Nil
664+ unMaybes Nil = Nil
665+instance MapMaybes xs => MapMaybes (x ': xs) where
666+ type Maybes (x ': xs) = Maybe x ': Maybes xs
667+ maybes (x :* xs) = I x :* maybes xs
668+ unMaybes (I mx :* xs) = mx :* unMaybes xs
669+
670+-- | `Nulls` is used to construct a `Squeal.Postgresql.Expression.row`
671+-- of a composite type.
672+type family Nulls tys where
673+ Nulls '[] = '[]
674+ Nulls (field ::: ty ': tys) = field ::: 'Null ty ': Nulls tys
468
675
469-- | Check if a `TableConstraint` involves a column
676-- | Check if a `TableConstraint` involves a column
470type family ConstraintInvolves column constraint where
677type family ConstraintInvolves column constraint where
@@ -486,111 +693,201 @@ type family DropIfConstraintsInvolve column constraints where
486-- `View` or `Typedef`.
693-- `View` or `Typedef`.
487data SchemumType
694data SchemumType
488 = Table TableType
695 = Table TableType
489− | View RowType
696+ | View RelationType
490 | Typedef PGType
697 | Typedef PGType
491− | Index IndexType
492− | Function FunctionType
493− | Operator OperatorType
494− | UnsafeSchemum Symbol
495−
496−type FunctionType = ([NullityType], ReturnsType)
497−
498−data IndexType
499− = Btree
500− | Hash
501− | Gist
502− | Spgist
503− | Gin
504− | Brin
505−
506−data ReturnsType
507− = Returns NullityType
508− | ReturnsTable RowType
509−
510−data OperatorType
511− = BinaryOp NullityType NullityType NullityType
512− | LeftOp NullityType NullityType
513− | RightOp NullityType NullityType
514−
515−{- | The schema of a database consists of a list of aliased,
516−user-defined `SchemumType`s.
517−
518−>>> :{
519−type family Schema :: SchemaType where
520− Schema =
521− '[ "users" ::: 'Table (
522− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
523− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
524− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
525− ])
526− , "emails" ::: 'Table (
527− '[ "pk_emails" ::: 'PrimaryKey '["id"]
528− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
529− ] :=>
530− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
531− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
532− , "email" ::: 'NoDef :=> 'Null 'PGtext
533− ])
534− ]
535−:}
536−-}
537−type SchemaType = [(Symbol,SchemumType)]
538−
539−{- |
540−A database contains one or more named schemas, which in turn contain tables.
541−The same object name can be used in different schemas without conflict;
542−for example, both schema1 and myschema can contain tables named mytable.
543−Unlike databases, schemas are not rigidly separated:
544−a user can access objects in any of the schemas in the database they are connected to,
545−if they have privileges to do so.
546
698
547−There are several reasons why one might want to use schemas:
699+-- | The schema of a database consists of a list of aliased,
548−
700+-- user-defined `SchemumType`s.
549− * To allow many users to use one database without interfering with each other.
701+type SchemaType = [(Symbol,SchemumType)]
550− * To organize database objects into logical groups to make them more manageable.
551− * Third-party applications can be put into separate schemas
552− so they do not collide with the names of other objects.
553−-}
554−type SchemasType = [(Symbol,SchemaType)]
555
702
556−-- | A type family to use for a single schema database.
703+-- | Used in `Squeal.Postgresql.Manipulation.with`.
704+type family With
705+ (relations :: RelationsType)
557−type family Public (schema :: SchemaType) :: SchemasType
706+ (schema :: SchemaType)
558− where Public schema = '["public" ::: schema]
707+ :: SchemaType where
708+ With '[] schema = schema
709+ With (alias ::: rel ': rels) schema =
710+ alias ::: 'View rel ': With rels schema
559
711
560-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas
712-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas
561-- the overloaded label, `fromLabel` is used for column references,
713-- the overloaded label, `fromLabel` is used for column references,
562-- `label`s are used for enum terms. A `label` is called with
714-- `label`s are used for enum terms. A `label` is called with
563-- type application like `label @"beef"`.
715-- type application like `label @"beef"`.
564class IsPGlabel (label :: Symbol) expr where label :: expr
716class IsPGlabel (label :: Symbol) expr where label :: expr
565−instance label ~ label1
717+instance label ~ label'
566− => IsPGlabel label (PGlabel label1) where label = PGlabel
718+ => IsPGlabel label (PGlabel label') where label = PGlabel
567−instance labels ~ '[label]
568− => IsPGlabel label (NP PGlabel labels) where label = PGlabel :* Nil
569-- | A `PGlabel` unit type with an `IsPGlabel` instance
719-- | A `PGlabel` unit type with an `IsPGlabel` instance
570data PGlabel (label :: Symbol) = PGlabel
720data PGlabel (label :: Symbol) = PGlabel
721+-- | Renders a label
571−instance KnownSymbol label => RenderSQL (PGlabel label) where
722+renderLabel :: KnownSymbol label => proxy label -> ByteString
572− renderSQL _ = "\'" <> renderSymbol @label <> "\'"
723+renderLabel (_ :: proxy label) =
724+ "\'" <> fromString (symbolVal (Proxy @label)) <> "\'"
725+-- | Renders a list of labels
726+renderLabels
573−instance All KnownSymbol labels => RenderSQL (NP PGlabel labels) where
727+ :: All KnownSymbol labels => NP PGlabel labels -> [ByteString]
574− renderSQL
575− = commaSeparated
576− . hcollapse
728+renderLabels = hcollapse
577− . hcmap (Proxy @KnownSymbol) (K . renderSQL)
729+ . hcmap (Proxy @KnownSymbol) (K . renderLabel)
730+
731+-- | The `PG` type family embeds a subset of Haskell types
732+-- as Postgres basic types.
733+--
734+-- >>> :kind! PG LocalTime
735+-- PG LocalTime :: PGType
736+-- = 'PGtimestamp
737+type family PG (hask :: Type) :: PGType where
738+ PG Bool = 'PGbool
739+ PG Int16 = 'PGint2
740+ PG Int32 = 'PGint4
741+ PG Int64 = 'PGint8
742+ PG Word16 = 'PGint2
743+ PG Word32 = 'PGint4
744+ PG Word64 = 'PGint8
745+ PG Scientific = 'PGnumeric
746+ PG Float = 'PGfloat4
747+ PG Double = 'PGfloat8
748+ PG Char = 'PGchar 1
749+ PG Text = 'PGtext
750+ PG Lazy.Text = 'PGtext
751+ PG ByteString = 'PGbytea
752+ PG Lazy.ByteString = 'PGbytea
753+ PG LocalTime = 'PGtimestamp
754+ PG UTCTime = 'PGtimestamptz
755+ PG Day = 'PGdate
756+ PG TimeOfDay = 'PGtime
757+ PG (TimeOfDay, TimeZone) = 'PGtimetz
758+ PG DiffTime = 'PGinterval
759+ PG UUID = 'PGuuid
760+ PG (NetAddr IP) = 'PGinet
761+ PG Value = 'PGjson
762+ PG ty = TypeError
763+ ('Text "There is no Postgres basic type for " ':<>: 'ShowType ty)
764+
765+-- | The `EnumFrom` type family embeds Haskell enum types, ADTs with
766+-- nullary constructors, as Postgres enum types
767+--
768+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
769+-- >>> instance Generic Schwarma
770+-- >>> instance HasDatatypeInfo Schwarma
771+-- >>> :kind! EnumFrom Schwarma
772+-- EnumFrom Schwarma :: PGType
773+-- = 'PGenum '["Beef", "Lamb", "Chicken"]
774+type family EnumFrom (hask :: Type) :: PGType where
775+ EnumFrom hask = 'PGenum (LabelsFrom hask)
776+
777+-- | The `LabelsFrom` type family calculates the constructors of a
778+-- Haskell enum type.
779+--
780+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
781+-- >>> instance Generic Schwarma
782+-- >>> instance HasDatatypeInfo Schwarma
783+-- >>> :kind! LabelsFrom Schwarma
784+-- LabelsFrom Schwarma :: [Type.ConstructorName]
785+-- = '["Beef", "Lamb", "Chicken"]
786+type family LabelsFrom (hask :: Type) :: [Type.ConstructorName] where
787+ LabelsFrom hask =
788+ ConstructorNamesOf (ConstructorsOf (DatatypeInfoOf hask))
789+
790+-- | The `CompositeFrom` type family embeds Haskell record types as
791+-- Postgres composite types, as long as the record fields
792+-- are `Maybe`s of Haskell types that can be embedded as basic types
793+-- with the `PG` type family.
794+--
795+-- >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
796+-- >>> instance Generic Row
797+-- >>> instance HasDatatypeInfo Row
798+-- >>> :kind! CompositeFrom Row
799+-- CompositeFrom Row :: PGType
800+-- = 'PGcomposite '['("a", 'PGint2), '("b", 'PGtimestamp)]
801+type family CompositeFrom (hask :: Type) :: PGType where
802+ CompositeFrom hask =
803+ 'PGcomposite (ZipAs (FieldNamesFrom hask) (FieldTypesFrom hask))
804+
805+-- | >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
806+-- >>> instance Generic Row
807+-- >>> instance HasDatatypeInfo Row
808+-- >>> :kind! FieldNamesFrom Row
809+-- FieldNamesFrom Row :: [Type.FieldName]
810+-- = '["a", "b"]
811+type family FieldNamesFrom (hask :: Type) :: [Type.FieldName] where
812+ FieldNamesFrom hask = FieldNamesOf (FieldsOf (DatatypeInfoOf hask))
813+
814+-- | >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
815+-- >>> instance Generic Row
816+-- >>> instance HasDatatypeInfo Row
817+-- >>> :kind! FieldTypesFrom Row
818+-- FieldTypesFrom Row :: [PGType]
819+-- = '['PGint2, 'PGtimestamp]
820+type family FieldTypesFrom (hask :: Type) :: [PGType] where
821+ FieldTypesFrom hask = FieldTypesOf (RecordCodeOf hask (Code hask))
822+
823+-- | Calculates constructors of a datatype.
824+type family ConstructorsOf (datatype :: Type.DatatypeInfo)
825+ :: [Type.ConstructorInfo] where
826+ ConstructorsOf ('Type.ADT _module _datatype constructors) =
827+ constructors
828+ ConstructorsOf ('Type.Newtype _module _datatype constructor) =
829+ '[constructor]
830+
831+-- | Calculates the name of a nullary constructor, otherwise
832+-- generates a type error.
833+type family ConstructorNameOf (constructors :: Type.ConstructorInfo)
834+ :: Type.ConstructorName where
835+ ConstructorNameOf ('Type.Constructor name) = name
836+ ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError
837+ ('Text "ConstructorNameOf error: non-nullary constructor "
838+ ':<>: 'Text name)
839+ ConstructorNameOf ('Type.Record name _fields) = TypeError
840+ ('Text "ConstructorNameOf error: non-nullary constructor "
841+ ':<>: 'Text name)
842+
843+-- | Calculate the names of nullary constructors.
844+type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])
845+ :: [Type.ConstructorName] where
846+ ConstructorNamesOf '[] = '[]
847+ ConstructorNamesOf (constructor ': constructors) =
848+ ConstructorNameOf constructor ': ConstructorNamesOf constructors
849+
850+-- | Calculate the fields of a datatype.
851+type family FieldsOf (datatype :: Type.DatatypeInfo)
852+ :: [Type.FieldInfo] where
853+ FieldsOf ('Type.ADT _module _datatype '[ 'Type.Record _name fields]) =
854+ fields
855+ FieldsOf ('Type.Newtype _module _datatype ('Type.Record _name fields)) =
856+ fields
857+
858+-- | Calculate the name of a field.
859+type family FieldNameOf (field :: Type.FieldInfo) :: Type.FieldName where
860+ FieldNameOf ('Type.FieldInfo name) = name
861+
862+-- | Calculate the names of fields.
863+type family FieldNamesOf (fields :: [Type.FieldInfo])
864+ :: [Type.FieldName] where
865+ FieldNamesOf '[] = '[]
866+ FieldNamesOf (field ': fields) = FieldNameOf field ': FieldNamesOf fields
867+
868+-- | >>> :kind! FieldTypeOf (Maybe Int16)
869+-- FieldTypeOf (Maybe Int16) :: PGType
870+-- = 'PGint2
871+type family FieldTypeOf (maybe :: Type) where
872+ FieldTypeOf (Maybe hask) = PG hask
873+ FieldTypeOf ty = TypeError
874+ ('Text "FieldTypeOf error: non-Maybe type " ':<>: 'ShowType ty)
875+
876+-- | Calculate the types of fields.
877+type family FieldTypesOf (fields :: [Type]) where
878+ FieldTypesOf '[] = '[]
879+ FieldTypesOf (field ': fields) = FieldTypeOf field ': FieldTypesOf fields
880+
881+-- | Inspect the code of an algebraic datatype and ensure it's a product,
882+-- otherwise generate a type error
883+type family RecordCodeOf (hask :: Type) (code ::[[Type]]) :: [Type] where
884+ RecordCodeOf _hask '[tys] = tys
885+ RecordCodeOf hask _tys = TypeError
886+ ('Text "RecordCodeOf error: non-Record type " ':<>: 'ShowType hask)
578
887
579-- | Is a type a valid JSON key?
888-- | Is a type a valid JSON key?
580−type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]
889+type PGjsonKey key = key `In` '[ 'PGint2, 'PGint4, 'PGtext ]
581
890
582-- | Is a type a valid JSON type?
891-- | Is a type a valid JSON type?
583−type PGJsonType = '[ 'PGjson, 'PGjsonb ]
892+type PGjson_ json = json `In` '[ 'PGjson, 'PGjsonb ]
584−
893+
585−-- | Utility class for `AllUnique` to provide nicer error messages.
586−class IsNotElem x isElem where
587−instance IsNotElem x 'False where
588−instance (TypeError ( 'Text "Cannot assign to "
589− ':<>: 'ShowType alias
590− ':<>: 'Text " more than once"))
591− => IsNotElem '(alias, a) 'True where
592−
593−-- | No elem of @xs@ appears more than once, in the context of assignment.
594−class AllUnique (xs :: [(Symbol, a)]) where
595−instance AllUnique '[] where
596−instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where
squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+74−101
@@ -1,7 +1,7 @@
1{-|
1{-|
2Module: Squeal.PostgreSQL.Transaction
2Module: Squeal.PostgreSQL.Transaction
3Description: Squeal transaction control language
3Description: Squeal transaction control language
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
5Maintainer: eitan@morphism.tech
5Maintainer: eitan@morphism.tech
6Stability: experimental
6Stability: experimental
7
7
@@ -9,125 +9,98 @@ Squeal transaction control language.
9-}
9-}
10
10
11{-# LANGUAGE
11{-# LANGUAGE
12− DataKinds
13− , FlexibleContexts
12+ FlexibleContexts
14 , LambdaCase
13 , LambdaCase
15 , OverloadedStrings
14 , OverloadedStrings
16− , TypeInType
17#-}
15#-}
18
16
19module Squeal.PostgreSQL.Transaction
17module Squeal.PostgreSQL.Transaction
20 ( -- * Transaction
18 ( -- * Transaction
21 transactionally
19 transactionally
22 , transactionally_
20 , transactionally_
23− , transactionallyRetry
24− , ephemerally
25− , ephemerally_
26 , begin
21 , begin
27 , commit
22 , commit
28 , rollback
23 , rollback
24+ , transactionallySchema
25+ , transactionallySchema_
29 -- * Transaction Mode
26 -- * Transaction Mode
30 , TransactionMode (..)
27 , TransactionMode (..)
31 , defaultMode
28 , defaultMode
32 , longRunningMode
29 , longRunningMode
33 , IsolationLevel (..)
30 , IsolationLevel (..)
31+ , renderIsolationLevel
34 , AccessMode (..)
32 , AccessMode (..)
33+ , renderAccessMode
35 , DeferrableMode (..)
34 , DeferrableMode (..)
35+ , renderDeferrableMode
36 ) where
36 ) where
37
37
38−import UnliftIO
38+import Control.Exception.Lifted
39+import Control.Monad.Base
40+import Control.Monad.Trans.Control
41+import Data.ByteString
42+import Data.Monoid
43+import Generics.SOP
44+
45+import qualified Database.PostgreSQL.LibPQ as LibPQ
39
46
40import Squeal.PostgreSQL.Manipulation
47import Squeal.PostgreSQL.Manipulation
41import Squeal.PostgreSQL.Render
48import Squeal.PostgreSQL.Render
42import Squeal.PostgreSQL.PQ
49import Squeal.PostgreSQL.PQ
50+import Squeal.PostgreSQL.Schema
43
51
44−{- | Run a computation `transactionally`;
52+-- | Run a schema invariant computation `transactionally`.
45−first `begin`,
46−then run the computation,
47−`onException` `rollback` and rethrow the exception,
48−otherwise `commit` and `return` the result.
49−-}
50transactionally
53transactionally
51− :: (MonadUnliftIO tx, MonadPQ schemas tx)
54+ :: (MonadBaseControl IO tx, MonadPQ schema tx)
52 => TransactionMode
55 => TransactionMode
53 -> tx x -- ^ run inside a transaction
56 -> tx x -- ^ run inside a transaction
54 -> tx x
57 -> tx x
55transactionally mode tx = mask $ \restore -> do
58transactionally mode tx = mask $ \restore -> do
56− manipulate_ $ begin mode
59+ _ <- begin mode
57− result <- restore tx `onException` (manipulate_ rollback)
60+ result <- restore tx `onException` rollback
58− manipulate_ commit
61+ _ <- commit
59 return result
62 return result
60
63
61−-- | Run a computation `transactionally_`, in `defaultMode`.
64+-- | Run a schema invariant computation `transactionally_` in `defaultMode`.
62transactionally_
65transactionally_
63− :: (MonadUnliftIO tx, MonadPQ schemas tx)
66+ :: (MonadBaseControl IO tx, MonadPQ schema tx)
64 => tx x -- ^ run inside a transaction
67 => tx x -- ^ run inside a transaction
65 -> tx x
68 -> tx x
66transactionally_ = transactionally defaultMode
69transactionally_ = transactionally defaultMode
67
70
68−{- |
69−`transactionallyRetry` a computation;
70−
71−* first `begin`,
72−* then `try` the computation,
73− - if it raises a serialization failure then `rollback` and restart the transaction,
74− - if it raises any other exception then `rollback` and rethrow the exception,
75− - otherwise `commit` and `return` the result.
76−-}
77−transactionallyRetry
78− :: (MonadUnliftIO tx, MonadPQ schemas tx)
79− => TransactionMode
80− -> tx x -- ^ run inside a transaction
81− -> tx x
82−transactionallyRetry mode tx = mask $ \restore ->
83− loop . try $ do
84− x <- restore tx
85− manipulate_ commit
86− return x
87− where
88− loop attempt = do
89− manipulate_ $ begin mode
90− attempt >>= \case
91− Left (PQException (PQState _ (Just "40001") _)) -> do
92− manipulate_ rollback
93− loop attempt
94− Left err -> do
95− manipulate_ rollback
96− throwIO err
97− Right x -> return x
98−
99−{- | Run a computation `ephemerally`;
100−Like `transactionally` but always `rollback`, useful in testing.
101−-}
102−ephemerally
103− :: (MonadUnliftIO tx, MonadPQ schemas tx)
104− => TransactionMode
105− -> tx x -- ^ run inside an ephemeral transaction
106− -> tx x
107−ephemerally mode tx = mask $ \restore -> do
108− manipulate_ $ begin mode
109− result <- restore tx `onException` (manipulate_ rollback)
110− manipulate_ rollback
111− return result
112−
113−{- | Run a computation `ephemerally` in `defaultMode`. -}
114−ephemerally_
115− :: (MonadUnliftIO tx, MonadPQ schemas tx)
116− => tx x -- ^ run inside an ephemeral transaction
117− -> tx x
118−ephemerally_ = ephemerally defaultMode
119−
120-- | @BEGIN@ a transaction.
71-- | @BEGIN@ a transaction.
121−begin :: TransactionMode -> Manipulation_ schemas () ()
72+begin :: MonadPQ schema tx => TransactionMode -> tx (K Result NilRelation)
122−begin mode = UnsafeManipulation $ "BEGIN" <+> renderSQL mode
73+begin mode = manipulate . UnsafeManipulation $
74+ "BEGIN" <+> renderTransactionMode mode <> ";"
123
75
124−-- | @COMMIT@ a transaction.
76+-- | @COMMIT@ a schema invariant transaction.
125−commit :: Manipulation_ schemas () ()
77+commit :: MonadPQ schema tx => tx (K Result NilRelation)
126−commit = UnsafeManipulation "COMMIT"
78+commit = manipulate $ UnsafeManipulation "COMMIT;"
127
79
128−-- | @ROLLBACK@ a transaction.
80+-- | @ROLLBACK@ a schema invariant transaction.
129−rollback :: Manipulation_ schemas () ()
81+rollback :: MonadPQ schema tx => tx (K Result NilRelation)
130−rollback = UnsafeManipulation "ROLLBACK"
82+rollback = manipulate $ UnsafeManipulation "ROLLBACK;"
83+
84+-- | Run a schema changing computation `transactionallySchema`.
85+transactionallySchema
86+ :: MonadBaseControl IO io
87+ => TransactionMode
88+ -> PQ schema0 schema1 io x
89+ -> PQ schema0 schema1 io x
90+transactionallySchema mode u = PQ $ \ conn -> mask $ \ restore -> do
91+ _ <- liftBase . LibPQ.exec (unK conn) $
92+ "BEGIN" <+> renderTransactionMode mode <> ";"
93+ x <- restore (unPQ u conn)
94+ `onException` (liftBase (LibPQ.exec (unK conn) "ROLLBACK"))
95+ _ <- liftBase $ LibPQ.exec (unK conn) "COMMIT"
96+ return x
97+
98+-- | Run a schema changing computation `transactionallySchema_` in `DefaultMode`.
99+transactionallySchema_
100+ :: MonadBaseControl IO io
101+ => PQ schema0 schema1 io x
102+ -> PQ schema0 schema1 io x
103+transactionallySchema_ = transactionallySchema defaultMode
131
104
132-- | The available transaction characteristics are the transaction `IsolationLevel`,
105-- | The available transaction characteristics are the transaction `IsolationLevel`,
133-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.
106-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.
@@ -140,7 +113,7 @@ data TransactionMode = TransactionMode
140-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
113-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
141-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.
114-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.
142defaultMode :: TransactionMode
115defaultMode :: TransactionMode
143−defaultMode = TransactionMode ReadCommitted ReadWrite NotDeferrable
116+defaultMode = TransactionMode Serializable ReadWrite NotDeferrable
144
117
145-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
118-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
146-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.
119-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.
@@ -149,12 +122,12 @@ longRunningMode :: TransactionMode
149longRunningMode = TransactionMode Serializable ReadOnly Deferrable
122longRunningMode = TransactionMode Serializable ReadOnly Deferrable
150
123
151-- | Render a `TransactionMode`.
124-- | Render a `TransactionMode`.
152−instance RenderSQL TransactionMode where
125+renderTransactionMode :: TransactionMode -> ByteString
153− renderSQL mode =
126+renderTransactionMode mode =
154− "ISOLATION LEVEL"
127+ "ISOLATION LEVEL"
155− <+> renderSQL (isolationLevel mode)
128+ <+> renderIsolationLevel (isolationLevel mode)
156− <+> renderSQL (accessMode mode)
129+ <+> renderAccessMode (accessMode mode)
157− <+> renderSQL (deferrableMode mode)
130+ <+> renderDeferrableMode (deferrableMode mode)
158
131
159-- | The SQL standard defines four levels of transaction isolation.
132-- | The SQL standard defines four levels of transaction isolation.
160-- The most strict is `Serializable`, which is defined by the standard in a paragraph
133-- The most strict is `Serializable`, which is defined by the standard in a paragraph
@@ -205,12 +178,12 @@ data IsolationLevel
205 deriving (Show, Eq)
178 deriving (Show, Eq)
206
179
207-- | Render an `IsolationLevel`.
180-- | Render an `IsolationLevel`.
208−instance RenderSQL IsolationLevel where
181+renderIsolationLevel :: IsolationLevel -> ByteString
209− renderSQL = \case
182+renderIsolationLevel = \case
210− Serializable -> "SERIALIZABLE"
183+ Serializable -> "SERIALIZABLE"
211− ReadCommitted -> "READ COMMITTED"
184+ ReadCommitted -> "READ COMMITTED"
212− ReadUncommitted -> "READ UNCOMMITTED"
185+ ReadUncommitted -> "READ UNCOMMITTED"
213− RepeatableRead -> "REPEATABLE READ"
186+ RepeatableRead -> "REPEATABLE READ"
214
187
215-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.
188-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.
216-- `ReadWrite` is the default. When a transaction is `ReadOnly`,
189-- `ReadWrite` is the default. When a transaction is `ReadOnly`,
@@ -227,10 +200,10 @@ data AccessMode
227 deriving (Show, Eq)
200 deriving (Show, Eq)
228
201
229-- | Render an `AccessMode`.
202-- | Render an `AccessMode`.
230−instance RenderSQL AccessMode where
203+renderAccessMode :: AccessMode -> ByteString
231− renderSQL = \case
204+renderAccessMode = \case
232− ReadWrite -> "READ WRITE"
205+ ReadWrite -> "READ WRITE"
233− ReadOnly -> "READ ONLY"
206+ ReadOnly -> "READ ONLY"
234
207
235-- | The `Deferrable` transaction property has no effect
208-- | The `Deferrable` transaction property has no effect
236-- unless the transaction is also `Serializable` and `ReadOnly`.
209-- unless the transaction is also `Serializable` and `ReadOnly`.
@@ -246,7 +219,7 @@ data DeferrableMode
246 deriving (Show, Eq)
219 deriving (Show, Eq)
247
220
248-- | Render a `DeferrableMode`.
221-- | Render a `DeferrableMode`.
249−instance RenderSQL DeferrableMode where
222+renderDeferrableMode :: DeferrableMode -> ByteString
250− renderSQL = \case
223+renderDeferrableMode = \case
251− Deferrable -> "DEFERRABLE"
224+ Deferrable -> "DEFERRABLE"
252− NotDeferrable -> "NOT DEFERRABLE"
225+ NotDeferrable -> "NOT DEFERRABLE"
squeal-postgresql/test/Doc.hsdeleted−6
@@ -1,6 +0,0 @@
1−module Main (main) where
2−
3−import Test.DocTest
4−
5−main :: IO ()
6−main = doctest [ "-isrc", "src" ]
squeal-postgresql/test/DocTest.hsnew file+18
@@ -0,0 +1,18 @@
1+module Main (main) where
2+
3+import Test.DocTest
4+
5+main :: IO ()
6+main = doctest
7+ [ "-isrc"
8+ , "src/Squeal/PostgreSQL.hs"
9+ , "src/Squeal/PostgreSQL/Binary.hs"
10+ , "src/Squeal/PostgreSQL/Definition.hs"
11+ , "src/Squeal/PostgreSQL/Manipulation.hs"
12+ , "src/Squeal/PostgreSQL/Query.hs"
13+ , "src/Squeal/PostgreSQL/Expression.hs"
14+ , "src/Squeal/PostgreSQL/PQ.hs"
15+ , "src/Squeal/PostgreSQL/Migration.hs"
16+ , "src/Squeal/PostgreSQL/Transaction.hs"
17+ , "src/Squeal/PostgreSQL/Pool.hs"
18+ ]
squeal-postgresql/test/Property.hsdeleted−166
@@ -1,166 +0,0 @@
1−{-# LANGUAGE
2− DataKinds
3− , GADTs
4− , LambdaCase
5− , OverloadedLabels
6− , OverloadedStrings
7− , TypeApplications
8− , TypeOperators
9−#-}
10−
11−module Main (main) where
12−
13−import Control.Monad.Trans
14−import Data.ByteString (ByteString)
15−import Data.ByteString.Char8 (unpack)
16−import Data.Scientific (fromFloatDigits)
17−import Data.Fixed (Fixed(MkFixed), Micro, Pico)
18−import Data.String (IsString(fromString))
19−import Data.Time
20−import Squeal.PostgreSQL hiding (check, defaultMain, Group)
21−import Hedgehog hiding (Range)
22−import qualified Hedgehog.Gen as Gen
23−import qualified Hedgehog.Main as Main
24−import qualified Hedgehog.Range as Range
25−
26−main :: IO ()
27−main = Main.defaultMain [checkSequential roundtrips]
28−
29−roundtrips :: Group
30−roundtrips = Group "roundtrips"
31− [ roundtrip int2 genInt16
32− , roundtrip int4 genInt32
33− , roundtrip int8 genInt64
34− , roundtrip bool Gen.bool
35− , roundtrip numeric genScientific
36− , roundtrip float4 genFloat
37− , roundtrip float8 genDouble
38− , roundtripOn normalizeTimeOfDay time genTimeOfDay
39− -- , roundtrip timetz genTimeWithZone normalizeTimeWithZone
40− , roundtripOn normalizeLocalTime timestamp genLocalTime
41− , roundtrip timestamptz genUTCTime
42− , roundtrip date genDay
43− , roundtrip interval genDiffTime
44− , roundtripOn normalizeIntRange int4range (genRange genInt32)
45− , roundtripOn normalizeIntRange int8range (genRange genInt64)
46− , roundtrip numrange (genRange genScientific)
47− , roundtripOn (fmap normalizeLocalTime) tsrange (genRange genLocalTime)
48− , roundtrip tstzrange (genRange genUTCTime)
49− , roundtripOn normalizeIntRange daterange (genRange genDay)
50− ]
51− where
52− genInt16 = Gen.int16 Range.exponentialBounded
53− genInt32 = Gen.int32 Range.exponentialBounded
54− genInt64 = Gen.int64 Range.exponentialBounded
55− genScientific = fromFloatDigits <$> genFloat
56− genPosFloat = Gen.float
57− (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)
58− genFloat = Gen.prune $ Gen.choice
59− [ genPosFloat
60− , negate <$> genPosFloat
61− , Gen.element [0,1/0] ]
62− genPosDouble = Gen.double
63− (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)
64− genDouble = Gen.prune $ Gen.choice
65− [ genPosDouble
66− , negate <$> genPosDouble
67− , Gen.element [0,1/0] ]
68− genRange gen = do
69− lb <- gen
70− ub <- Gen.filter (lb <) gen
71− Gen.element
72− [ Empty, singleton lb, whole
73− , lb <=..<= ub , lb <=..< ub, lb <..<= ub, lb <..< ub
74− , atLeast lb, moreThan lb, atMost ub, lessThan ub ]
75− genDay = do
76− y <- toInteger <$> Gen.int (Range.constant 2000 2019)
77− m <- Gen.int (Range.constant 1 12)
78− d <- Gen.int (Range.constant 1 28)
79− return $ fromGregorian y m d
80− genDiffTime = secondsToDiffTime . toInteger <$>
81− Gen.int (Range.constant 0 86401)
82− genUTCTime = UTCTime <$> genDay <*> genDiffTime
83− genTimeOfDay = do
84− h <- Gen.int (Range.constant 0 23)
85− m <- Gen.int (Range.constant 0 59)
86− s <- MkFixed . toInteger <$> Gen.int (Range.constant 0 59)
87− return $ TimeOfDay h m s
88− genLocalTime = LocalTime <$> genDay <*> genTimeOfDay
89− -- genTimeZone = Gen.element $ map (read @TimeZone)
90− -- [ "UTC", "UT", "GMT", "EST", "EDT", "CST"
91− -- , "CDT", "MST", "MDT", "PST", "PDT" ]
92− -- genTimeWithZone = (,) <$> genTimeOfDay <*> genTimeZone
93−
94−roundtrip
95− :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)
96− => TypeExpression schemas ('NotNull ty)
97− -> Gen x
98− -> (PropertyName, Property)
99−roundtrip = roundtripOn id
100−
101−roundtripOn
102− :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)
103− => (x -> x)
104− -> TypeExpression schemas ('NotNull ty)
105− -> Gen x
106− -> (PropertyName, Property)
107−roundtripOn norm ty gen = propertyWithName $ do
108− x <- forAll gen
109− Just (Only y) <- lift . withConnection connectionString $
110− firstRow =<< runQueryParams
111− (values_ (parameter @1 ty `as` #fromOnly)) (Only x)
112− norm x === y
113− where
114− propertyWithName prop =
115− (fromString (unpack (renderSQL ty)), property prop)
116−
117−maxPosFloat :: RealFloat a => a
118−maxPosFloat = x
119− where
120− n = floatDigits x
121− b = floatRadix x
122− (_, u) = floatRange x
123− x = encodeFloat (b^n - 1) (u - n)
124−
125−minPosFloat :: RealFloat a => a
126−minPosFloat = x
127− where
128− n = floatDigits x
129− b = floatRadix x
130− (l, _) = floatRange x
131− x = encodeFloat (b^n - 1) (l - n - 1)
132−
133−connectionString :: ByteString
134−connectionString = "host=localhost port=5432 dbname=exampledb"
135−
136−normalizeIntRange :: (Enum int, Ord int) => Range int -> Range int
137−normalizeIntRange = \case
138− Empty -> Empty
139− NonEmpty l u ->
140− let
141− l' = normalizeL l
142− u' = normalizeU u
143− in if emptyNormalized l' u' then Empty else NonEmpty l' u'
144− where
145− normalizeL = \case
146− Open l -> Closed (succ l)
147− normalized -> normalized
148− normalizeU = \case
149− Closed u -> Open (succ u)
150− normalized -> normalized
151− emptyNormalized (Closed l) (Open u) = l >= u
152− emptyNormalized _ _ = False
153−
154−normalizeTimeOfDay :: TimeOfDay -> TimeOfDay
155−normalizeTimeOfDay (TimeOfDay h m s) = TimeOfDay h m
156− . fromRational @Pico
157− . toRational @Micro
158− . fromRational @Micro
159− . toRational @Pico
160− $ s
161−
162−normalizeLocalTime :: LocalTime -> LocalTime
163−normalizeLocalTime (LocalTime d t) = LocalTime d (normalizeTimeOfDay t)
164−
165−-- normalizeTimeWithZone :: (TimeOfDay, TimeZone) -> (TimeOfDay, TimeZone)
166−-- normalizeTimeWithZone (t, z) = (normalizeTimeOfDay t, z)
squeal-postgresql/test/Spec.hsdeleted−136
@@ -1,136 +0,0 @@
1−{-# LANGUAGE
2− DataKinds
3− , DeriveAnyClass
4− , DeriveGeneric
5− , DerivingStrategies
6− , DuplicateRecordFields
7− , FlexibleContexts
8− , OverloadedLabels
9− , OverloadedLists
10− , OverloadedStrings
11− , TypeApplications
12− , TypeFamilies
13− , TypeInType
14− , TypeOperators
15−#-}
16−
17−module Main (main) where
18−
19−import Control.Concurrent.Async (replicateConcurrently)
20−import Data.ByteString (ByteString)
21−import Data.Int (Int32)
22−import Data.Text (Text)
23−import Test.Hspec
24−
25−import qualified Generics.SOP as SOP
26−import qualified GHC.Generics as GHC
27−
28−import Squeal.PostgreSQL
29−
30−main :: IO ()
31−main = hspec spec
32−
33−type Schemas = Public
34− '[ "users" ::: 'Table (
35− '[ "pk_users" ::: 'PrimaryKey '["id"]
36− , "unique_names" ::: 'Unique '["name"]
37− ] :=>
38− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
39− , "name" ::: 'NoDef :=> 'NotNull 'PGtext ] ) ]
40−
41−data User = User
42− { userName :: Text
43− } deriving stock (Eq, Show, GHC.Generic)
44− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)
45−
46−insertUser :: Manipulation_ Schemas User ()
47−insertUser = insertInto_ #users
48− (Values_ (Default `as` #id :* Set (param @1) `as` #name))
49−
50−setup :: Definition (Public '[]) Schemas
51−setup =
52− createTable #users
53− ( serial `as` #id :*
54− notNullable text `as` #name )
55− ( primaryKey #id `as` #pk_users :*
56− unique #name `as` #unique_names )
57−
58−teardown :: Definition Schemas (Public '[])
59−teardown = dropTable #users
60−
61−silence :: MonadPQ schemas pq => pq ()
62−silence = manipulate_ $
63− UnsafeManipulation "SET client_min_messages TO WARNING;"
64−
65−setupDB :: IO ()
66−setupDB = withConnection connectionString $
67− silence & pqThen (define setup)
68−
69−dropDB :: IO ()
70−dropDB = withConnection connectionString $
71− silence & pqThen (define teardown)
72−
73−connectionString :: ByteString
74−connectionString = "host=localhost port=5432 dbname=exampledb"
75−
76−spec :: Spec
77−spec = before_ setupDB . after_ dropDB $ do
78−
79− describe "Exceptions" $ do
80−
81− let
82− testUser = User "TestUser"
83− newUser = manipulateParams_ insertUser
84− insertUserTwice = newUser testUser >> newUser testUser
85− err23505 = PQException $ PQState FatalError (Just "23505")
86− (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")
87−
88− it "should be thrown for constraint violation" $
89− withConnection connectionString insertUserTwice
90− `shouldThrow` (== err23505)
91−
92− it "should be rethrown for constraint violation in a transaction" $
93− withConnection connectionString (transactionally_ insertUserTwice)
94− `shouldThrow` (== err23505)
95−
96− describe "Pools" $
97−
98− it "should manage concurrent transactions" $ do
99− pool <- createConnectionPool
100− "host=localhost port=5432 dbname=exampledb" 1 0.5 10
101− let
102− query :: Query_ (Public '[]) () (Only Char)
103− query = values_ (literal 'a' `as` #fromOnly)
104− session = usingConnectionPool pool . transactionally_ $ do
105− result <- runQuery query
106− Just (Only chr) <- firstRow result
107− return chr
108− chrs <- replicateConcurrently 10 session
109− chrs `shouldSatisfy` all (== 'a')
110−
111− describe "Ranges" $
112−
113− it "should correctly decode ranges" $ do
114−
115− rangesOut <- withConnection connectionString $ do
116− let
117− query :: Query_ (Public '[]) () (Only (Range Int32))
118− query = values
119− ( range int4range (atLeast 3) `as` #fromOnly )
120− [ range int4range (3 <=..< 5) `as` #fromOnly
121− , range int4range Empty `as` #fromOnly
122− , range int4range whole `as` #fromOnly ]
123− getRows =<< runQuery query
124− (fromOnly <$> rangesOut :: [Range Int32]) `shouldBe`
125− [ atLeast 3, 3 <=..< 5, Empty, whole ]
126−
127− describe "Parameters" $ do
128−
129− it "should run queries that don't reference all their parameters" $ do
130−
131− out <- withConnection connectionString $ do
132− let
133− query :: Query_ (Public '[]) (Char,Int32) (Only Int32)
134− query = values_ (param @2 `as` #fromOnly)
135− firstRow =<< runQueryParams query ('a', 3 :: Int32)
136− (fromOnly <$> out :: Maybe Int32) `shouldBe` Just 3
squeal-presentation-raveline.mddeleted−794
@@ -1,794 +0,0 @@
1−# Squeal
2−
3−_A bridge between SQL and Haskell_
4−
5−by [@Raveline](https://github.com/raveline)
6−
7−---
8−
9−# Rationale
10−
11−Using `postgresql-simple` you have a typical "Trial, error, despair" workflow:
12−
13−- Write query manually or semi-automatically
14−
15−- Write haskell code using the query
16−
17−- Pray that the query syntax is correct
18−
19−- Pray that it returns what you want
20−
21−- Realize the inefficiency of prayer when it comes to SQL
22−
23−- Iterate till it works
24−
25−---
26−
27−![Can't take this anymore](http://gif.eraveline.eu/static/img/0x16e.gif)
28−
29−---
30−
31−# Use your best friend: GHC
32−
33−Squeal provides several eDSL to make your SQL typesafe:
34−
35−- Type level eDSL to express schema;
36−
37−- Value level eDSL to manipulate schema (plus migration, yeehaw !);
38−
39−- Type level eDSL to express queries;
40−
41−- Value level eDSL to perform queries
42−
43−However, it's not an ORM. There's no caching, lazy loading - you retain control over your memory. Also, joins - and mostly aggregation after joins - have to be handled manually.
44−
45−---
46−
47−# Part I. Schema & migration
48−
49−---
50−
51−# The Schema
52−
53−- The schema will be used to validate _everything_: migration, queries, etc.
54−
55−- A schema is mostly a collection of tables.
56−
57−- In this presentation, we will create a very basic database modeling a parliament. We will store _members of parliament_ and _parliamentary groups_.
58−
59−- A simple Schema to represent a Parliament could be:
60−
61−```haskell
62−type Schema = '[ "mp" ::: 'Table MemberOfParliament
63− , "groupp" ::: 'Table ParliamentGroup ]
64−```
65−
66−---
67−
68−> _note_ We need the `DataKinds` extension to be able to express heterogenous lists containing
69−> specific types like this one.
70−
71−> You can perfectly call your table "group" and not "groupp" even though it is a
72−> keyword in SQL - Squeal queries will be properly escaped.
73−
74−---
75−
76−# A small example
77−
78−```haskell
79−type ParliamentaryGroup =
80− '[ "pk_groupp" ::: 'PrimaryKey '["groupp_id"]]
81− :=>
82− '[ "groupp_id" ::: 'NoDef :=> 'NotNull 'PGuuid
83− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
84− ]
85−```
86−
87−- That's a whole simple table defined in one go.
88−
89−- `:::` lets us define a column or a constraint.
90−
91−- `:=>` associates the constraints to the column.
92−
93−- Let's split constraints and column to study the syntax a bit more.
94−
95−---
96−
97−> _note_ We are using `:::` and `:=>` to quickly express associations when writing
98−> our schema. We need the `TypeOperators` extension.]
99−
100−---
101−
102−![What does this means ?!](http://gif.eraveline.eu/static/img/0x27e.gif)
103−
104−---
105−
106−# Defining a table
107−
108−```haskell
109−type MemberOfParliament =
110− '[ "pk_mp" ::: 'PrimaryKey '["mp_id"]
111− , "fk_mp_groupp" ::: 'ForeignKey '["mp_group"] "groupp" '["groupp_id"]
112− ] :=> MpCols
113−```
114−
115−- A table is a collection of constraints associated to a collection of columns.
116−
117−- We defined a table named "mp".
118−
119−- It has a constraint named "pk_mp", defining its primary key on column "mp_id".
120−
121−- It has a constraint named "fk_mp_groupp" defining a foreign key on column "mg_group", connected to the column "groupp_id" of table "groupp".
122−
123−- These constraints will be associated to the columns defined in `MpCols`.
124−
125−---
126−
127−# Defining columns
128−
129−```haskell
130−type MpCols =
131− '[ "mp_id" ::: 'NoDef :=> 'NotNull 'PGuuid
132− , "first_name" ::: 'NoDef :=> 'NotNull 'PGtext
133− , "last_name" ::: 'NoDef :=> 'NotNull 'PGtext
134− ]
135−```
136−
137−- A listing of column associate, for each element:
138−
139− * a name;
140−
141− * the mention of an eventual default value;
142−
143− * the nullability;
144−
145− * the type (obviously).
146−
147−---
148−
149−> _note_ GHC is already helping. If I named the "mp_id" column differently,
150−> GHC would yell because I promised a primary key constraint on a column named `mp_id`, so there must be one.]
151−
152−---
153−
154−# Implementating the schema
155−
156−- We will carry this schema type pretty much everywhere.
157−
158−- But before we play with this schema, we need to implement it.
159−
160−---
161−
162−```haskell
163−setup :: Definition '[] Schema
164−setup =
165− createTable #groupp
166− ( notNullable uuid `as` #groupp_id
167− :* notNullable text `as` #name)
168− ( primaryKey #groupp_id `as` #pk_groupp )
169− >>> createTable #mp
170− ( notNullable uuid `as` #mp_id
171− :* notNullable text `as` #first_name
172− :* notNullable text `as` #last_name
173− :* notNullable text `as` #mp_group)
174− ( primaryKey #mp_id `as` #pk_mp
175− :* foreignKey #mp_group #groupp #groupp_id
176− OnDeleteCascade OnUpdateCascade
177− `as` #fk_mp_groupp)
178−```
179−
180−---
181−
182−# Damn, that's verbose
183−
184−- Yes. But you need verbosity to get type safety.
185−
186−- On the plus side, it's fairly straightforward.
187−
188−- You use `:*` to compose the element of the heterogenous list of columns.
189−
190−- You use `>>>` to compose table creation.
191−
192−> _note_ The compiler will catch any mistype between Schema and
193−> definition; wrong nullability, wrong type, wrong name, etc.
194−
195−---
196−
197−> _note_ You'll also need `OverloadedLabels`, for naming stuff.
198−> This is mostly to avoid having to write manual proxies all
199−> the time and for convenience.
200−
201−---
202−
203−# Setting up the schema
204−
205−- Squeal comes with a very good migration manager, handling _upgrades_ AND
206−_downgrades_.
207−
208−- A migration is a simple type:
209−
210−```haskell
211−Migration io schema0 schema1
212−```
213−
214−- The first parameter is a BaseMonad (typically, IO).
215−
216−- The second parameter is "the current schema of your DB".
217−
218−- The last one is "what you will migrate to".
219−
220−- The `Definition` type used to define upgrade and downgrade functions use the
221− same logic (from one schema to the other).
222−
223−---
224−
225−# Defining our first migration
226−
227−- We have the setup bit, we need the teardown:
228−
229−```haskell
230−tearDown :: Definition Schema '[]
231−tearDown = dropTable #mp >>> dropTable #groupp
232−```
233−
234−> _note_ GHC will also detect the _proper_ order of what you typed in
235−> downgrade and upgrade should there be any conflict (with foreign keys).
236−
237−```haskell
238−initDB :: Migration IO '[] Schema
239−initDB =
240− Migration { name = "Schema creation"
241− , up = void $ define setup
242− , down = void $ define tearDown }
243−```
244−
245−---
246−
247−# Simple migrator example
248−
249−```haskell
250−main :: IO ()
251−main = do
252− printSQL setup
253− void $ withConnection connectionString $
254− migrateUp $ single initDB
255−```
256−
257−- We print the migration query; you can do this for all queries generated through Squeal.
258−
259−- We use `migrateUp` to perform the migration.
260−
261−- You can run several migration at the same time, to run only one use `single`.
262−
263−---
264−
265−![That was easy](http://gif.eraveline.eu/static/img/0x47f.gif)
266−
267−---
268−
269−# Part II. Insertions
270−
271−---
272−
273−# Manipulations & Queries
274−
275−Besides the specific case of migration, you will mostly perform:
276−
277−- `Manipulation` : inserting, updating and deleting data.
278−
279−- `Query` : fetching data.
280−
281−- Both types are parametric over the same things:
282−
283− * A schema
284−
285− * Input parameters
286−
287− * Output
288−
289−- Simplified, they look like this:
290−
291−```haskell
292−Manipulation schema params columns
293−
294−Query schema params columns
295−```
296−
297−
298−---
299−
300−# Our Haskell model
301−
302−```haskell
303−type Parliament = [Group]
304−
305−data Group =
306− Group { name :: Text
307− , members :: [MemberOfParliament] }
308−
309−data MemberOfParliament =
310− MemberOfParliament { firstName :: Text
311− , lastName :: Text }
312−```
313−
314−> _note_ We didn't use anything from Squeal.
315−> The model can be entirely separated from the persistence layer.
316−
317−---
318−
319−# Inserting a Parliamentary Group
320−
321−- A group is very simple: it's a uuid and a name. Let's define our params:
322−
323−```haskell
324−type GroupInsertionParams = '[ 'NotNull 'PGuuid
325− , 'NotNull 'PGtext ]
326−```
327−
328−- Params are not named, but they are indexed. You just need nullability and type.
329−
330−---
331−
332−```haskell
333−groupInsertion :: Manipulation Schema GroupInsertionParams '[]
334−groupInsertion =
335− insertRow_ #groupp ( Set (param @1) `as` #groupp_id
336− :* Set (param @2) `as` #name )
337−```
338−
339−---
340−
341−- `TypeApplication` lets us use the index of parameters (counting from 1).
342−
343−- Once again: all this is checked by the compiler. Wrong name, wrong type... you'll get a compile error.
344−
345−- `insertRow_` is a simplified version of `insertRow`. `insertRow` lets you express a `RETURNING` clause and the expected behaviour in case of conflict.
346−
347−---
348−
349−_Inserting a Member of Parliament_
350−# Doing an INSERT INTO ... SELECT
351−
352−- We could create a naive query that takes MP uuid, first name, last name and group uuid...
353−
354−---
355−
356−- But that's boring. So let's use the `INSERT INTO ... SELECT`.
357−
358−---
359−
360−- We will build a query that will return as constants our MP's uuid, first name and last name...
361−
362−---
363−
364−- ... and fetch the uuid of a group given the name of the group.
365−
366−---
367−
368−- There's a `insertQuery` utility function for that. All we have to do is write the `select` !
369−
370−```haskell
371−mpInsertion :: Manipulation Schema MpParams '[]
372−mpInsertion =
373− insertQuery_ #mp selectGroup -- we just have to write selectGroup !
374−```
375−
376−---
377−
378−_Inserting a Member of Parliament_
379−# The query type
380−
381−- A query looks just like a `Manipulation`:
382−
383−```haskell
384−Query schema params returns
385−```
386−
387−- Returns use a special syntax, that demands names, nullability and types:
388−
389−```haskell
390−type ExampleReturnType = '[ "some_column" ::: 'NotNull 'PGuuid
391− , "other_column" ::: 'Null 'PGtext ]
392−```
393−
394−- It is not the same as the column definition we used in the schema. That one also expects that you specify, for each column, an eventual default:
395−
396−```haskell
397−type ExampleSchemaCols =
398− '[ "some_column" ::: 'NoDef :=> 'NotNull 'PGuuid
399− , "other_column" ::: 'NoDef :=> 'Null 'PGtext ]
400−```
401−
402−---
403−
404−_Inserting a Member of Parliament_
405−# Don't rewrite column definitions
406−
407−- We want our return type to be "all columns from table MP expressed as return type".
408−
409−- But we cannot reuse our neat `MpCols` alias, since the type do not match as we've just seen.
410−
411−- Hopefully, there's a neat Type Family that will let you convert any table you defined to the type of the equivalent row: `TableToRow`.
412−
413−- We finally have the signature for our SELECT query.
414−
415−```haskell
416−selectGroup :: Query Schema MpParams (TableToRow MemberOfParliament)
417−```
418−
419−---
420−
421−_Inserting a Member of Parliament_
422−# Our final Select query
423−
424−- Our intermediate query looks like this:
425−
426−```haskell
427−selectGroup =
428− select
429− ( param @1 `as` #mp_id
430− :* param @2 `as` #first_name
431− :* param @3 `as` #last_name
432− :* #groupp ! #groupp_id `as` #mp_group
433− )
434− ( from (table #groupp)
435− & where_ ( #groupp ! #name .== param @4 )
436− )
437−```
438−
439−- The first three columns are constant defined through our params;
440−
441−- ... we alias the column name using `as`...
442−
443−- ... and when we need the result from the table we use the `#table ! #column` syntax.
444−
445−- We'll go back to the "from" block later.
446−
447−---
448−
449−# Dealing with the connection context
450−
451−- Queries are runned in a connection context:
452−
453− * When dealing with a single-connection context, use the type `PQ`.
454−
455− * When dealing with a pool of connection, use the type `PoolPQ`.
456−
457−- Or get rid of the context and use `mtl` style, with the typeclass `MonadPQ`.
458−
459−- We'll use that to demonstrate how to actually run our queries.
460−
461−---
462−
463−# Inserting a whole group
464−
465−```haskell
466−insertGroup :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()
467−insertGroup g@(Group name _) = do
468− uuid' <- liftBase nextRandom
469− void $ manipulateParams groupInsertion (uuid', name)
470− insertMps g
471−```
472−
473−- Remember that we defined a group as a name and a list of MPs.
474−
475−- We are in `MonadBaseControl`, so we cannot use `liftIO`, we need `liftBase`.
476−
477−- To perform a simple insertion, use `manipulateParams`. It takes into parameter
478−instances of `ToParam`, but you will typically use tuples or Generic-SOP.
479−
480−---
481−
482−# Inserting a bunch of MPs
483−
484−```haskell
485−insertMps :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()
486−insertMps (Group groupName mps) =
487− let tuplify Mp{..} = (, firstName, lastName, groupName) <$> nextRandom
488− params = traverse tuplify mps
489− in void $ liftBase params >>= traversePrepared mpInsertion
490−```
491−
492−- This time, we want to do a `preparedStatement`. We'll use `traversePrepare`
493−which behaves like `manipulateParams`, but expect a list of `ToParam`
494−instances.
495−
496−- We build our tuple manually again, mostly because we want to generate UUID on
497−the fly and we don't want to have them in our model.
498−
499−---
500−
501−# Inserting a whole parliament
502−
503−```haskell
504−insertParliament ::
505− (MonadPQ Schema m, MonadBaseControl IO m) => Parliament -> m ()
506−insertParliament = traverse_ insertGroup
507−```
508−
509−- That's simple enough !
510−
511−- If we want to be a bit safer, though, we can wrap this call in a
512−`transactionally_` function, which will put all that in a transaction.
513−
514−---
515−
516−![Very simple](https://media1.tenor.com/images/0188c63209aced59f1583e1ca94e509e/tenor.gif?itemid=3550689)
517−
518−
519−---
520−
521−# Part III. Selects
522−
523−---
524−
525−# Composable queries
526−
527−- Building basic queries is easy, and is well documented.
528−
529−- However, the real interest of a tool like Squeal is in DRYness, and the documentation is still lacking in "how-to" related to composability.
530−
531−- I'll build an example showing how column selections and from clause can be factorized.
532−
533−- We want to write two queries:
534−
535− * One to get all members of a specific group.
536−
537− * One to get all the parliament.
538−
539−---
540−
541−# Decomposing a `Query`
542−
543−- A query typically stars with `select` (variants are available).
544−
545−- It then takes:
546−
547− * A heterogenous list of fields with a scary signature;
548−
549− * A virtual table (the from clause and filter clauses), called a `TableExpression`.
550−
551−- And return fields. Ours will look like this:
552−
553−```haskell
554−type GroupRowResult =
555− '[ "groupName" ::: 'NotNull 'PGtext
556− , "firstName" ::: 'NotNull 'PGtext
557− , "lastName" ::: 'NotNull 'PGtext ]
558−```
559−
560−---
561−
562−# The Table Expression
563−
564−- It necessarily contains a `fromClause` (table, view or subquery, plus optional joins).
565−
566−- You can add where, groups, "HAVING" clause, order, etc.
567−
568−- `from` creates a basic `TableExpression` that you extend through various function to add clauses.
569−
570−- For our queries, we will share a common `FromClause`.
571−
572−---
573−
574−# The From Clause
575−
576−```
577−FromClause schema params from
578−```
579−
580−- We need Schema, input parameters and a `FromType` giving the available fields of the expression.
581−
582−- In our case, we'll join the table `mp` and the table `groupp`, meaning the `from` will be all fields of these tables.
583−
584−- We can use `TableToRow` to be more DRY:
585−
586−```haskell
587−type BaseParliamentSelection =
588− '[ "g" ::: TableToRow GroupCols
589− , "m" ::: TableToRow MpCols ]
590−```
591−
592−> _note_ We've also put everything with table aliases: "g" and "m".
593−
594−---
595−
596−# Writing our from clause
597−
598−```haskell
599−baseParliamentTables ::
600− FromClause Schema (param :: [NullityType]) BaseParliamentSelection
601−baseParliamentTables =
602− table
603− (#groupp `as` #g)
604− & innerJoin
605− (table (#mp `as` #m))
606− (#m ! #mp_group .== #g ! #groupp_id)
607−```
608−
609−- When picking "from" something, you need to specify the type with a function: `table` for a table, `view` for a view, etc.
610−
611−- All joins are available. `innerJoin` is the most basic one. It takes the joined table and the joining condition.
612−
613−- We have to specifiy the type of `param` (current limitation of the lib), even though _any_ params will be compatible with this, so we can plug `where` clauses depending on params should we need to !
614−
615−---
616−
617−# Typing the common selection
618−
619−- Both our querie will need the same fields. This has to be factorized too.
620−
621−- The scary signature of selection fields:
622−
623−```haskell
624−NP (Aliased (Expression schema from grouping params)) cols
625−```
626−
627−- `NP` is for heterogenous lists ("n-ary product").
628−
629−- `from` is the virtual table type, so our `BaseParliamentSelection`.
630−
631−- `grouping` is there to make a distinction between aggregated / unaggregated queries.
632−
633−- And finally, cols is the return type.
634−
635−---
636−
637−# Our common selection
638−
639−```haskell
640−groupSelection ::
641− NP (Aliased (Expression Schema BaseParliamentSelection 'Ungrouped param))
642− GroupRowResult
643−groupSelection =
644− #g ! #name `as` #groupName
645− :* #m ! #first_name `as` #firstName
646− :* #m ! #last_name `as` #lastName
647−```
648−
649−- I hope you like big signatures.
650−
651−- But it's what let GHC checks that all alias and columns are available.
652−
653−- And that you're returning what you really intend to return.
654−
655−---
656−
657−# Putting it all together
658−
659−```haskell
660−selectParliament :: Query Schema '[] GroupRowResult
661−selectParliament =
662− select groupSelection (from baseParliamentTables)
663−```
664−
665−```haskell
666−selectGroupMembers :: Query Schema '[ 'NotNull 'PGtext] GroupRowResult
667−selectGroupMembers =
668− select groupSelection
669− (from baseParliamentTables
670− & where_ (#g ! #name .== param @1))
671−```
672−
673−- That is fairly DRY. And _entirely typesafe_.
674−
675−---
676−
677−# Actually fetching the data
678−
679−- We'll build an intermediary datatype representing our rows.
680−
681−- We'll make it match our row.
682−
683−- And we'll add generic-SOP so that we can build them from query results.
684−
685−```haskell
686−type GroupRowResult =
687− '[ "groupName" ::: 'NotNull 'PGtext
688− , "firstName" ::: 'NotNull 'PGtext
689− , "lastName" ::: 'NotNull 'PGtext ]
690−```
691−
692−```haskell
693−data GroupRow =
694− GroupRow { groupName :: Text
695− , firstName :: Text
696− , lastName :: Text }
697− deriving (Generic)
698−
699−instance SOP.Generic GroupRow
700−instance SOP.HasDatatypeInfo GroupRow
701−```
702−
703−---
704−
705−# Aggregate result logic
706−
707−- We will get tabular, SQL data.
708−
709−- Our results will be `[GroupRow]`.
710−
711−- We'll build `Groups` from this:
712−
713−```haskell
714−buildGroup :: NE.NonEmpty GroupRow -> Group
715−buildGroup grs =
716− let buildMP (GroupRow _ f l) = Mp f l
717− name = groupName . NE.head $ grs
718− members = NE.toList (buildMP <$> grs)
719− in Group{..}
720−
721−rowToGroups :: [GroupRow] -> [Group]
722−rowToGroups =
723− let grouped = fmap NE.fromList . L.groupBy ((==) `on` groupName)
724− in fmap buildGroup . grouped
725−```
726−
727−---
728−
729−# Finally calling our queries
730−
731−- Query with params will use `runQueryParams`.
732−
733−- Query without params will use `runQuery`.
734−
735−- Result is inside a `MonadPQ` and of type `K` from generic-sop.
736−
737−- You get your actual result using `getRows`. Exemple:
738−
739−```haskell
740−getParliament :: (MonadPQ Schema m, MonadBaseControl IO m) => m [Group]
741−getParliament = do
742− res <- runQuery selectParliament
743− rows <- getRows res
744− pure $ rowToGroups rows
745−```
746−
747−- In real life of course you'll write:
748−
749−```haskell
750−getParliament =
751− rowToGroups <$> (runQuery selectParliament >>= getRows)
752−```
753−
754−---
755−
756−# Our query with params
757−
758−```haskell
759−getGroupMembers ::
760− (MonadPQ Schema m, MonadBaseControl IO m) => Text -> m (Maybe Group)
761−getGroupMembers =
762− listToMaybe . rowToGroups <$>
763− (runQueryParams selectGroupMembers (Only t) >>= getRows)
764−```
765−
766−- And that's it.
767−
768−---
769−
770−![Eazy](https://media.tenor.com/images/8fc7c4077efe11b4a3a3b9ae4e643e87/tenor.gif)
771−
772−---
773−
774−# Conclusion
775−
776−---
777−
778−# Pros & Cons
779−
780−- Not everything is included: some cool stuff like array_agg and window functions are not available yet.
781−
782−- But development is _very_ active. `IN` clauses were missing but were added in the 4.0 released recently.
783−
784−- It's bleeding edge. You need latest LTS to be comfortable and psql >= 9.5.
785−
786−- It's Postgres-only but I would say that's a feature. Multi-DB tools are even more complex.
787−
788−- The author & maintainer is <3.
789−
790−- Typesafe. 'nuff said.
791−
792−---
793−
794−# Thank you !
stack.yaml+1−6
@@ -1,8 +1,3 @@
1−resolver: nightly-2019-07-14
1+resolver: lts-11.15
2packages:
2packages:
3- squeal-postgresql
3- squeal-postgresql
4−
5−extra-deps:
6−- unliftio-pool-0.2.1.0
7−- github: morphismtech/free-categories
8− commit: c0e555fbefb5c21619e532264c4dfeac556d0630