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unifiedsplit
.circleci/config.yml+2−3 README.md+87−83 RELEASE NOTES.md−818 squeal-postgresql/exe/Example.hs+38−35 squeal-postgresql/squeal-postgresql.cabal+11−71 squeal-postgresql/src/Squeal/PostgreSQL.hs+95−101 squeal-postgresql/src/Squeal/PostgreSQL/Alias.hs−249 squeal-postgresql/src/Squeal/PostgreSQL/Binary.hs+221−534 squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+918−23 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Function.hs−238 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Index.hs−159 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Schema.hs−96 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table.hs−500 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table/Constraint.hs−339 squeal-postgresql/src/Squeal/PostgreSQL/Definition/Type.hs−229 squeal-postgresql/src/Squeal/PostgreSQL/Definition/View.hs−104 squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+1574−340 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hs−462 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Collection.hs−169 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Comparison.hs−206 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Json.hs−462 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Literal.hs−87 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Logic.hs−105 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Math.hs−100 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Null.hs−104 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Parameter.hs−80 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Range.hs−230 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Set.hs−139 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Sort.hs−85 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Subquery.hs−120 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Text.hs−64 squeal-postgresql/src/Squeal/PostgreSQL/Expression/TextSearch.hs−157 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Time.hs−192 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Type.hs−446 squeal-postgresql/src/Squeal/PostgreSQL/Expression/Window.hs−284 squeal-postgresql/src/Squeal/PostgreSQL/List.hs−112 squeal-postgresql/src/Squeal/PostgreSQL/Manipulation.hs+339−410 squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+206−338 squeal-postgresql/src/Squeal/PostgreSQL/PG.hs−388 squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+211−312 squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+104−73 squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+624−648 squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+17−58 squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+635−310 squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+74−101 squeal-postgresql/test/Doc.hs−6 squeal-postgresql/test/DocTest.hs+18 squeal-postgresql/test/Property.hs−166 squeal-postgresql/test/Spec.hs−136 squeal-presentation-raveline.md−794 stack.yaml+1−6
.circleci/config.yml+2−3
@@ -2,10 +2,9 @@ version: 2
22jobs:
33 build:
44 docker:
5− - image: haskell:8.6.5
5+ - image: haskell:8.2.2
66 - image: circleci/postgres:latest
77 environment:
8− POSTGRES_USER: root
98 POSTGRES_DB: exampledb
109 steps:
1110 - checkout
@@ -14,7 +13,7 @@ jobs:
1413 - dependency-cache
1514 - run: apt-get update && apt-get install -y libpq-dev xz-utils make
1615 - run: stack upgrade && stack update
17− - run: stack build --fast
16+ - run: stack build
1817 - run: stack test
1918 - run: stack haddock
2019 - save_cache:
README.md+87−83
@@ -45,12 +45,7 @@ composable and cover a large portion of SQL.
4545* connection pools
4646* transactions
4747* views
48−* array, composite and enumerated types
49−* json functions and operations
50−* multischema support
51−* correlated subqueries
52−* window functions
53−* text search
48+* composite and enumerated types
5449
5550## installation
5651
@@ -58,16 +53,10 @@ composable and cover a large portion of SQL.
5853
5954## testing
6055
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`.
6257
6358`stack test`
6459
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−
7160## usage
7261
7362Let's see an example!
@@ -76,17 +65,19 @@ First, we need some language extensions because Squeal uses modern GHC
7665features.
7766
7867```Haskell
79−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
80−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
68+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
69+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators
8170```
8271
8372We'll need some imports.
8473
8574```Haskell
86−>>> import Control.Monad.IO.Class (liftIO)
75+>>> import Control.Monad (void)
76+>>> import Control.Monad.Base (liftBase)
8777>>> import Data.Int (Int32)
8878>>> import Data.Text (Text)
8979>>> import Squeal.PostgreSQL
80+>>> import Squeal.PostgreSQL.Render
9081```
9182
9283We'll use generics to easily convert between Haskell and PostgreSQL values.
@@ -101,27 +92,27 @@ we use `DataKinds` and `TypeOperators`.
10192
10293```Haskell
10394>>> :{
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"] ]
11595type Schema =
116− '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)
117− , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]
118−type Schemas = Public Schema
96+ '[ "users" ::: 'Table (
97+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
98+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
99+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
100+ ])
101+ , "emails" ::: 'Table (
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+ ]
119110:}
120111```
121112
122113Notice the use of type operators.
123114
124−`:::` is used to pair an alias `Symbol` with a `SchemumType`,
115+`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemumType`,
125116a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's `::`
126117operator.
127118
@@ -130,7 +121,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
130121yielding a `ColumnType`. It is intended to connote Haskell's `=>` operator
131122
132123Next, 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`
134125has two type parameters, corresponding to the schema
135126before being run and the schema after. We can compose definitions using `>>>`.
136127Here 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.
139130```Haskell
140131>>> :{
141132let
142− setup :: Definition (Public '[]) Schemas
143− setup =
133+ setup :: Definition '[] Schema
134+ setup =
144135 createTable #users
145− ( serial `as` #id :*
146− (text & notNullable) `as` #name )
147− ( primaryKey #id `as` #pk_users ) >>>
136+ ( serial `As` #id :*
137+ (text & notNullable) `As` #name :* Nil )
138+ ( primaryKey #id `As` #pk_users :* Nil ) >>>
148139 createTable #emails
149− ( serial `as` #id :*
150− (int & notNullable) `as` #user_id :*
151− (text & nullable) `as` #email )
152− ( primaryKey #id `as` #pk_emails :*
140+ ( serial `As` #id :*
141+ (int & notNullable) `As` #user_id :*
142+ (text & nullable) `As` #email :* Nil )
143+ ( primaryKey #id `As` #pk_emails :*
153144 foreignKey #user_id #users #id
154− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
145+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )
155146:}
156147```
157148
@@ -171,7 +162,7 @@ primary and foreign keys, making them somewhat complex. Our `teardown`
171162```Haskell
172163>>> :{
173164let
174− teardown :: Definition Schemas (Public '[])
165+ teardown :: Definition Schema '[]
175166 teardown = dropTable #emails >>> dropTable #users
176167:}
177168
@@ -180,57 +171,57 @@ DROP TABLE "emails";
180171DROP TABLE "users";
181172```
182173
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.
193−A `Manipulation_` like `insertInto`, `update` or `deleteFrom`
194−has three type parameters, the schemas it refers to, input parameters
195−and an output row. When
174+Next, we'll write `Manipulation`s to insert data into our two tables.
175+A `Manipulation` like `insertRow`, `update` or `deleteFrom`
176+has three type parameters, the schema it refers to, a list of parameters
177+it can take as input, and a list of columns it produces as output. When
196178we insert into the users table, we will need a parameter for the `name`
197179field but not for the `id` field. Since it's serial, we can use a default
198180value. However, since the emails table refers to the users table, we will
199181need 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
201−`with` statement.
182+the emails table. Take a careful look at the type and definition of both
183+of our inserts.
202184
203185```Haskell
204186>>> :{
205187let
206− insertUser :: Manipulation_ Schemas User ()
207− insertUser = with (u `as` #u) e
208− where
209− u = insertInto #users
210− (Values_ (Default `as` #id :* Set (param @1) `as` #name))
211− OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))
212− e = insertInto_ #emails $ Select
213− (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)
214− (from (common #u))
188+ insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]
189+ insertUser = insertRow #users
190+ (Default `As` #id :* Set (param @1) `As` #name :* Nil)
191+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))
192+:}
193+
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)
215202:}
216203
217204>>> 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
219208```
220209
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
222211interested 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
224−`Manipulation_` with the same kind of type parameters.
212+need to use an inner join to get the right result. A `Query` is like a
213+`Manipulation` with the same kind of type parameters.
225214
226215```Haskell
227216>>> :{
228217let
229− getUsers :: Query_ Schemas () User
230− getUsers = select_
231− (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)
232− ( from (table (#users `as` #u)
233− & innerJoin (table (#emails `as` #e))
218+ getUsers :: Query Schema '[]
219+ '[ "userName" ::: 'NotNull 'PGtext
220+ , "userEmail" ::: 'Null 'PGtext ]
221+ getUsers = select
222+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* Nil)
223+ ( from (table (#users `As` #u)
224+ & innerJoin (table (#emails `As` #e))
234225 (#u ! #id .== #e ! #user_id)) )
235226:}
236227
@@ -238,13 +229,25 @@ let
238229SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
239230```
240231
241−Let's create some users to add to the database.
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+
244+Let's also create some users to add to the database.
242245
243246```Haskell
244247>>> :{
245248let
246249 users :: [User]
247− users =
250+ users =
248251 [ User "Alice" (Just "alice@gmail.com")
249252 , User "Bob" Nothing
250253 , User "Carole" (Just "carole@hotmail.com")
@@ -263,18 +266,19 @@ transformer and when the schema doesn't change we can use `Monad` and
263266```Haskell
264267>>> :{
265268let
266− session :: PQ Schemas Schemas IO ()
269+ session :: PQ Schema Schema IO ()
267270 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))
269274 usersResult <- runQuery getUsers
270275 usersRows <- getRows usersResult
271− liftIO $ print (usersRows :: [User])
276+ liftBase $ print (usersRows :: [User])
272277in
273− withConnection "host=localhost port=5432 dbname=exampledb" $
278+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
274279 define setup
275280 & pqThen session
276281 & pqThen (define teardown)
277282:}
278283[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
279−-}
280284```
RELEASE NOTES.md−818
@@ -1,823 +1,5 @@
11## RELEASE NOTES
22
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−
8213### Version 0.3.2 - August 4, 2018
8224
8235Version 0.3.2 features extensive support for `JSON` functionality with
squeal-postgresql/exe/Example.hs+38−35
@@ -11,7 +11,8 @@
1111
1212module Main (main, main2) where
1313
14−import Control.Monad.IO.Class (MonadIO (..))
14+import Control.Monad (void)
15+import Control.Monad.Base (liftBase, MonadBase)
1516import Data.Int (Int16, Int32)
1617import Data.Monoid ((<>))
1718import Data.Text (Text)
@@ -28,7 +29,7 @@ type Schema =
2829 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
2930 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
3031 , "name" ::: 'NoDef :=> 'NotNull 'PGtext
31− , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray ('Null 'PGint2))
32+ , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray 'PGint2)
3233 ])
3334 , "emails" ::: 'Table (
3435 '[ "pk_emails" ::: 'PrimaryKey '["id"]
@@ -38,13 +39,10 @@ type Schema =
3839 , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
3940 , "email" ::: 'NoDef :=> 'Null 'PGtext
4041 ])
41− , "positive" ::: 'Typedef 'PGfloat4
4242 ]
4343
44−type Schemas = Public Schema
45−
46−setup :: Definition (Public '[]) Schemas
47−setup =
44+setup :: Definition '[] Schema
45+setup =
4846 createTable #users
4947 ( serial `as` #id :*
5048 (text & notNullable) `as` #name :*
@@ -53,55 +51,60 @@ setup =
5351 >>>
5452 createTable #emails
5553 ( serial `as` #id :*
56− hask @Int32 `as` #user_id :*
57− hask @(Maybe Text) `as` #email )
54+ (int & notNullable) `as` #user_id :*
55+ (text & nullable) `as` #email )
5856 ( primaryKey #id `as` #pk_emails :*
5957 foreignKey #user_id #users #id
6058 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
61− >>>
62− createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
63−
64−teardown :: Definition Schemas (Public '[])
65−teardown = dropType #positive >>> dropTable #emails >>> dropTable #users
66−
67−insertUser :: Manipulation_ Schemas (Text, VarArray (Vector (Maybe Int16))) (Only Int32)
68−insertUser = insertInto #users
69− (Values_ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec))
70− (OnConflict (OnConstraint #pk_users) DoNothing) (Returning_ (#id `as` #fromOnly))
71−
72−insertEmail :: Manipulation_ Schemas (Int32, Maybe Text) ()
73−insertEmail = insertInto_ #emails
74− (Values_ (Default `as` #id :* Set (param @1) `as` #user_id :* Set (param @2) `as` #email))
7559
76−getUsers :: Query_ Schemas () User
77−getUsers = select_
60+teardown :: Definition Schema '[]
61+teardown = dropTable #emails >>> dropTable #users
62+
63+insertUser :: Manipulation Schema '[ 'NotNull 'PGtext, 'NotNull ('PGvararray 'PGint2)]
64+ '[ "fromOnly" ::: 'NotNull 'PGint4 ]
65+insertUser = insertRows #users
66+ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec) []
67+ OnConflictDoNothing (Returning (#id `as` #fromOnly))
68+
69+insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
70+insertEmail = insertRows #emails
71+ ( Default `as` #id :*
72+ Set (param @1) `as` #user_id :*
73+ Set (param @2) `as` #email ) []
74+ OnConflictDoNothing (Returning Nil)
75+
76+getUsers :: Query Schema '[]
77+ '[ "userName" ::: 'NotNull 'PGtext
78+ , "userEmail" ::: 'Null 'PGtext
79+ , "userVec" ::: 'NotNull ('PGvararray 'PGint2)]
80+getUsers = select
7881 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail :* #u ! #vec `as` #userVec)
7982 ( from (table (#users `as` #u)
8083 & innerJoin (table (#emails `as` #e))
8184 (#u ! #id .== #e ! #user_id)) )
8285
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) }
8487 deriving (Show, GHC.Generic)
8588instance SOP.Generic User
8689instance SOP.HasDatatypeInfo User
8790
8891users :: [User]
89−users =
90− [ User "Alice" (Just "alice@gmail.com") (VarArray [Nothing, Just 1])
91− , User "Bob" Nothing (VarArray [Just 2, Nothing])
92− , User "Carole" (Just "carole@hotmail.com") (VarArray [Just 3])
92+users =
93+ [ User "Alice" (Just "alice@gmail.com") [Nothing, Just 1]
94+ , User "Bob" Nothing [Just 2, Nothing]
95+ , User "Carole" (Just "carole@hotmail.com") [Just 3]
9396 ]
9497
95−session :: (MonadIO pq, MonadPQ Schemas pq) => pq ()
98+session :: (MonadBase IO pq, MonadPQ Schema pq) => pq ()
9699session = do
97− liftIO $ Char8.putStrLn "manipulating"
100+ liftBase $ Char8.putStrLn "manipulating"
98101 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])
99102 ids <- traverse (fmap fromOnly . getRow 0) idResults
100103 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
101− liftIO $ Char8.putStrLn "querying"
104+ liftBase $ Char8.putStrLn "querying"
102105 usersResult <- runQuery getUsers
103106 usersRows <- getRows usersResult
104− liftIO $ print (usersRows :: [User])
107+ liftBase $ print (usersRows :: [User])
105108
106109main :: IO ()
107110main = do
@@ -119,7 +122,7 @@ main = do
119122
120123main2 :: IO ()
121124main2 =
122− withConnection "host=localhost port=5432 dbname=exampledb" $
125+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
123126 define setup
124127 & pqThen session
125128 & pqThen (define teardown)
squeal-postgresql/squeal-postgresql.cabal+11−71
@@ -1,5 +1,5 @@
11name: squeal-postgresql
2−version: 0.5.1.0
2+version: 0.3.2.0
33synopsis: Squeal PostgreSQL Library
44description: Squeal is a type-safe embedding of PostgreSQL in Haskell
55homepage: https://github.com/morphismtech/squeal
@@ -22,40 +22,12 @@ library
2222 hs-source-dirs: src
2323 exposed-modules:
2424 Squeal.PostgreSQL
25− Squeal.PostgreSQL.Alias
2625 Squeal.PostgreSQL.Binary
2726 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
3527 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
5528 Squeal.PostgreSQL.Manipulation
5629 Squeal.PostgreSQL.Migration
5730 Squeal.PostgreSQL.Pool
58− Squeal.PostgreSQL.PG
5931 Squeal.PostgreSQL.PQ
6032 Squeal.PostgreSQL.Render
6133 Squeal.PostgreSQL.Query
@@ -65,73 +37,40 @@ library
6537 ghc-options: -Wall
6638 build-depends:
6739 aeson >= 1.2.4.0
68− , base >= 4.11.1.0 && < 5.0
40+ , base >= 4.10.1.0 && < 5.0
6941 , binary-parser >= 0.5.5
7042 , bytestring >= 0.10.8.2
7143 , bytestring-strict-builder >= 0.4.5
7244 , 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
7547 , mmorph >= 1.1.1
48+ , monad-control >= 1.0.2.3
7649 , mtl >= 2.2.2
7750 , network-ip >= 0.3.0.2
7851 , postgresql-binary >= 0.12.1
7952 , postgresql-libpq >= 0.9.4.1
80− , records-sop >= 0.1.0.0
53+ , profunctors >= 5.2.2
8154 , resource-pool >= 0.2.3.2
8255 , scientific >= 0.3.5.3
8356 , text >= 1.2.3.0
8457 , time >= 1.8.0.2
8558 , transformers >= 0.5.2.0
86− , unliftio >= 0.2.10
87− , unliftio-pool >= 0.2.1.0
59+ , transformers-base >= 0.4.4
8860 , uuid-types >= 1.0.3
8961 , vector >= 0.12.0.1
9062
91−test-suite doctest
63+test-suite squeal-postgresql-doctest
9264 default-language: Haskell2010
9365 type: exitcode-stdio-1.0
9466 hs-source-dirs: test
9567 ghc-options: -Wall
96− main-is: Doc.hs
68+ main-is: DocTest.hs
9769 build-depends:
9870 base >= 4.10.0.0
9971 , 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
13372
134−executable example
73+executable squeal-postgresql-example
13574 default-language: Haskell2010
13675 hs-source-dirs: exe
13776 ghc-options: -Wall
@@ -144,4 +83,5 @@ executable example
14483 , squeal-postgresql
14584 , text >= 1.2.2.2
14685 , transformers >= 0.5.2.0
86+ , transformers-base >= 0.4.4
14787 , vector >= 0.12.0.1
squeal-postgresql/src/Squeal/PostgreSQL.hs+95−101
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL
3−Description: Squeal export module
4−Copyright: (c) Eitan Chatav, 2019
3+Description: Squeel export module
4+Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -11,15 +11,17 @@ Let's see an example!
1111First, we need some language extensions because Squeal uses modern GHC
1212features.
1313
14−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
15−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
16−
14+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
15+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators
16+
1717We'll need some imports.
1818
19−>>> import Control.Monad.IO.Class (liftIO)
19+>>> import Control.Monad (void)
20+>>> import Control.Monad.Base (liftBase)
2021>>> import Data.Int (Int32)
2122>>> import Data.Text (Text)
2223>>> import Squeal.PostgreSQL
24+>>> import Squeal.PostgreSQL.Render
2325
2426We'll use generics to easily convert between Haskell and PostgreSQL values.
2527
@@ -30,26 +32,26 @@ The first step is to define the schema of our database. This is where
3032we use @DataKinds@ and @TypeOperators@.
3133
3234>>> :{
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"] ]
4435type Schema =
45− '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)
46− , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]
47−type Schemas = Public Schema
36+ '[ "users" ::: 'Table (
37+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
38+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
39+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
40+ ])
41+ , "emails" ::: 'Table (
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+ ]
4850:}
4951
5052Notice the use of type operators.
5153
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`,
5355a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's @::@
5456operator.
5557
@@ -58,7 +60,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
5860yielding a `ColumnType`. It is intended to connote Haskell's @=>@ operator
5961
6062Next, 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`
6264has two type parameters, corresponding to the schema
6365before being run and the schema after. We can compose definitions using `>>>`.
6466Here and in the rest of our commands we make use of overloaded
@@ -66,8 +68,8 @@ labels to refer to named tables and columns in our schema.
6668
6769>>> :{
6870let
69− setup :: Definition (Public '[]) Schemas
70− setup =
71+ setup :: Definition '[] Schema
72+ setup =
7173 createTable #users
7274 ( serial `as` #id :*
7375 (text & notNullable) `as` #name )
@@ -87,14 +89,14 @@ We can easily see the generated SQL is unsurprising looking.
8789CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
8890CREATE 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);
8991
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@.
9193In our `createTable` commands we included `TableConstraint`s to define
9294primary and foreign keys, making them somewhat complex. Our @teardown@
9395`Definition` is simpler.
9496
9597>>> :{
9698let
97− teardown :: Definition Schemas (Public '[])
99+ teardown :: Definition Schema '[]
98100 teardown = dropTable #emails >>> dropTable #users
99101:}
100102
@@ -102,49 +104,51 @@ let
102104DROP TABLE "emails";
103105DROP TABLE "users";
104106
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.
113−A `Manipulation_` like `insertInto`, `update` or `deleteFrom`
114−has three type parameters, the schemas it refers to, input parameters
115−and an output row. When
107+Next, we'll write `Manipulation`s to insert data into our two tables.
108+A `Manipulation` like `insertRow`, `update` or `deleteFrom`
109+has three type parameters, the schema it refers to, a list of parameters
110+it can take as input, and a list of columns it produces as output. When
116111we insert into the users table, we will need a parameter for the @name@
117112field but not for the @id@ field. Since it's serial, we can use a default
118113value. However, since the emails table refers to the users table, we will
119114need 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
121−`with` statement.
115+the emails table. Take a careful look at the type and definition of both
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)
123+ OnConflictDoNothing (Returning (#id `as` #fromOnly))
124+:}
122125
123126>>> :{
124127let
125− insertUser :: Manipulation_ Schemas User ()
126− insertUser = with (u `as` #u) e
127− where
128− u = insertInto #users
129− (Values_ (Default `as` #id :* Set (param @1) `as` #name))
130− OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))
131− e = insertInto_ #emails $ Select
132− (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)
133− (from (common #u))
128+ insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
129+ insertEmail = insertRow #emails
130+ ( Default `as` #id :*
131+ Set (param @1) `as` #user_id :*
132+ Set (param @2) `as` #email )
133+ OnConflictDoNothing (Returning Nil)
134134:}
135135
136136>>> 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
138140
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
140142interested 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
142−`Manipulation_` with the same kind of type parameters.
143+need to use an inner join to get the right result. A `Query` is like a
144+`Manipulation` with the same kind of type parameters.
143145
144146>>> :{
145147let
146− getUsers :: Query_ Schemas () User
147− getUsers = select_
148+ getUsers :: Query Schema '[]
149+ '[ "userName" ::: 'NotNull 'PGtext
150+ , "userEmail" ::: 'Null 'PGtext ]
151+ getUsers = select
148152 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)
149153 ( from (table (#users `as` #u)
150154 & innerJoin (table (#emails `as` #e))
@@ -154,12 +158,22 @@ let
154158>>> printSQL getUsers
155159SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
156160
157−Let's create some users to add to the database.
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+
171+Let's also create some users to add to the database.
158172
159173>>> :{
160174let
161175 users :: [User]
162− users =
176+ users =
163177 [ User "Alice" (Just "alice@gmail.com")
164178 , User "Bob" Nothing
165179 , User "Carole" (Just "carole@hotmail.com")
@@ -176,58 +190,38 @@ transformer and when the schema doesn't change we can use `Monad` and
176190
177191>>> :{
178192let
179− session :: PQ Schemas Schemas IO ()
193+ session :: PQ Schema Schema IO ()
180194 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))
182198 usersResult <- runQuery getUsers
183199 usersRows <- getRows usersResult
184− liftIO $ print (usersRows :: [User])
200+ liftBase $ print (usersRows :: [User])
185201in
186− withConnection "host=localhost port=5432 dbname=exampledb" $
202+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
187203 define setup
188204 & pqThen session
189205 & pqThen (define teardown)
190206:}
191207[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
192208-}
193−module Squeal.PostgreSQL (module X, RenderSQL(..), printSQL) where
194−
195−import Squeal.PostgreSQL.Alias as X
196−import Squeal.PostgreSQL.Binary as X
197−import Squeal.PostgreSQL.Definition as X
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
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
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
230−import Squeal.PostgreSQL.Query as X
231−import Squeal.PostgreSQL.Render (RenderSQL(..), printSQL)
232−import Squeal.PostgreSQL.Schema as X
233−import Squeal.PostgreSQL.Transaction as X
209+module Squeal.PostgreSQL
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+
220+import Squeal.PostgreSQL.Binary
221+import Squeal.PostgreSQL.Definition
222+import Squeal.PostgreSQL.Expression
223+import Squeal.PostgreSQL.Manipulation
224+import Squeal.PostgreSQL.PQ
225+import Squeal.PostgreSQL.Query
226+import Squeal.PostgreSQL.Schema
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
77
88This module provides binary encoding and decoding between Haskell and PostgreSQL types.
99
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
1111do not need to define your own instances to decode retrieved rows into Haskell values or
1212to encode Haskell values into statement parameters.
1313
14−Let's see some examples. We'll need some imports
15−
1614>>> import Data.Int (Int16)
1715>>> 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.
2416
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)
2618>>> instance Generic Row
2719>>> 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−:}
3620
37−So long as we can encode the parameters and then decode the result of the query,
38−the input and output should be equal.
21+>>> import Control.Monad (void)
22+>>> import Control.Monad.Base (liftBase)
23+>>> import Squeal.PostgreSQL
3924
40−>>> let input = Row 2 "hi" (Just True)
4125>>> :{
42−withConnection "host=localhost port=5432 dbname=exampledb" $ do
43− result <- runQueryParams roundTrip input
44− Just output <- firstRow result
45− liftIO . print $ input == output
26+let
27+ query :: Query '[]
28+ '[ 'NotNull 'PGint2, 'NotNull 'PGtext]
29+ '["col1" ::: 'NotNull 'PGint2, "col2" ::: 'NotNull 'PGtext]
30+ query = values_ (param @1 `as` #col1 :* param @2 `as` #col2)
4631:}
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.
6832
6933>>> :{
7034let
71− roundTrip :: Query_ (Public '[]) Row Row
72− roundTrip = values_ $
73− parameter @1 (int2 & vararray) `as` #col1 :*
74− parameter @2 (int2 & fixarray @'[2]) `as` #col2 :*
75− parameter @3 (int2 & fixarray @'[3,2]) `as` #col3
35+ roundtrip :: IO ()
36+ roundtrip = void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
37+ result <- runQueryParams query (2 :: Int16, "hi" :: Text)
38+ Just row <- firstRow result
39+ liftBase . print $ row == Row 2 "hi"
7640:}
7741
78−>>> :set -XOverloadedLists
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−:}
42+>>> roundtrip
8643True
8744
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+
8849Enumerated (enum) types are data types that comprise a static, ordered set of values.
8950They are equivalent to Haskell algebraic data types whose constructors are nullary.
9051An example of an enum type might be the days of the week,
9152or a set of status values for a piece of data.
9253
93−>>> data Schwarma = Beef | Lamb | Chicken deriving (Eq, Show, GHC.Generic)
54+>>> data Schwarma = Beef | Lamb | Chicken deriving (Show, GHC.Generic)
9455>>> instance Generic Schwarma
9556>>> instance HasDatatypeInfo Schwarma
9657
9758A 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.
9962
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)
10164>>> instance Generic Person
10265>>> instance HasDatatypeInfo Person
103−>>> instance Aeson.FromJSON Person
104−>>> instance Aeson.ToJSON Person
10566
10667We can create the equivalent Postgres types directly from their Haskell types.
10768
10869>>> :{
10970type Schema =
110− '[ "schwarma" ::: 'Typedef (PG (Enumerated Schwarma))
111− , "person" ::: 'Typedef (PG (Composite Person))
71+ '[ "schwarma" ::: 'Typedef (EnumFrom Schwarma)
72+ , "person" ::: 'Typedef (CompositeFrom Person)
11273 ]
11374:}
11475
11576>>> :{
11677let
117− setup :: Definition (Public '[]) (Public Schema)
78+ setup :: Definition '[] Schema
11879 setup =
11980 createTypeEnumFrom @Schwarma #schwarma >>>
12081 createTypeCompositeFrom @Person #person
12182:}
12283
123−Let's demonstrate how to associate our Haskell types @Schwarma@ and @Person@
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.
84+Then we can perform roundtrip queries;
12685
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
13786>>> :{
13887let
139− input = Row
140− (Enumerated Chicken)
141− (Composite (Person "Faisal" 24))
142− (Json (Person "Ahmad" 48))
88+ querySchwarma :: Query Schema
89+ '[ 'NotNull (EnumFrom Schwarma)]
90+ '["fromOnly" ::: 'NotNull (EnumFrom Schwarma)]
91+ querySchwarma = values_ (parameter @1 #schwarma `as` #fromOnly)
14392:}
14493
145−Once again, define a round trip query.
146−
14794>>> :{
14895let
149− roundTrip :: Query_ (Public Schema) Row Row
150− roundTrip = values_ $
151− parameter @1 (typedef #schwarma) `as` #schwarma :*
152− parameter @2 (typedef #person) `as` #person1 :*
153− parameter @3 json `as` #person2
96+ queryPerson :: Query Schema
97+ '[ 'NotNull (CompositeFrom Person)]
98+ '["fromOnly" ::: 'NotNull (CompositeFrom Person)]
99+ queryPerson = values_ (parameter @1 #person `as` #fromOnly)
154100:}
155101
156−Finally, we can drop our type definitions.
102+And finally drop the types.
157103
158104>>> :{
159105let
160− teardown :: Definition (Public Schema) (Public '[])
106+ teardown :: Definition Schema '[]
161107 teardown = dropType #schwarma >>> dropType #person
162108:}
163109
@@ -166,16 +112,20 @@ Now let's run it.
166112>>> :{
167113let
168114 session = do
169− result <- runQueryParams roundTrip input
170− Just output <- firstRow result
171− liftIO . print $ input == output
115+ result1 <- runQueryParams querySchwarma (Only Chicken)
116+ Just (Only schwarma) <- firstRow result1
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)
172121in
173− withConnection "host=localhost port=5432 dbname=exampledb" $
122+ void . withConnection "host=localhost port=5432 dbname=exampledb" $
174123 define setup
175124 & pqThen session
176125 & pqThen (define teardown)
177126:}
178−True
127+Chicken
128+Person {name = Just "Faisal", age = Just 24}
179129-}
180130
181131{-# LANGUAGE
@@ -184,76 +134,55 @@ True
184134 , DeriveFunctor
185135 , DeriveGeneric
186136 , DeriveTraversable
187− , DefaultSignatures
188137 , FlexibleContexts
189138 , FlexibleInstances
190− , FunctionalDependencies
191139 , GADTs
192140 , LambdaCase
193− , OverloadedStrings
194141 , MultiParamTypeClasses
195142 , ScopedTypeVariables
196143 , TypeApplications
197− , TypeFamilies
198144 , TypeInType
199145 , TypeOperators
200146 , UndecidableInstances
201− , UndecidableSuperClasses
202147#-}
203148
204149module Squeal.PostgreSQL.Binary
205150 ( -- * Encoding
206151 ToParam (..)
152+ , ToColumnParam (..)
207153 , ToParams (..)
208− , ToNullityParam (..)
209− , ToField (..)
210− , ToFixArray (..)
211154 -- * Decoding
212155 , FromValue (..)
156+ , FromColumnValue (..)
213157 , FromRow (..)
214− , FromField (..)
215− , FromFixArray (..)
216158 -- * Only
217159 , Only (..)
218− -- * Oid
219− , OidOf (..)
220− , OidOfParam (..)
221− , OidOfField (..)
222160 ) where
223161
224162import BinaryParser
225−import ByteString.StrictBuilder (builderLength, int32BE, int64BE, word32BE)
226−import Control.Arrow (left)
227−import Control.Monad
163+import ByteString.StrictBuilder
164+import Data.Aeson hiding (Null)
228165import Data.Int
229166import Data.Kind
167+import Data.Monoid hiding (All)
230168import Data.Scientific
231169import Data.Time
232170import Data.UUID.Types
233171import Data.Vector (Vector)
234172import Data.Word
235−import Foreign.C.Types (CUInt(CUInt))
236173import Generics.SOP
237−import Generics.SOP.Record
238174import GHC.TypeLits
239175import Network.IP.Addr
240176
241−import qualified Data.Aeson as Aeson
242−import qualified Data.ByteString.Lazy as Lazy (ByteString)
243−import qualified Data.ByteString.Lazy as Lazy.ByteString
244−import qualified Data.ByteString as Strict (ByteString)
245−import qualified Data.Text.Lazy as Lazy (Text)
246−import qualified Data.Text as Strict (Text)
247−import qualified Data.Text as Strict.Text
177+import qualified Data.ByteString.Lazy as Lazy
178+import qualified Data.ByteString as Strict hiding (pack, unpack)
179+import qualified Data.Text.Lazy as Lazy
180+import qualified Data.Text as Strict
248181import qualified Data.Vector as Vector
249−import qualified Database.PostgreSQL.LibPQ as LibPQ
250182import qualified GHC.Generics as GHC
251183import qualified PostgreSQL.Binary.Decoding as Decoding
252184import qualified PostgreSQL.Binary.Encoding as Encoding
253185
254−import Squeal.PostgreSQL.Alias
255−import Squeal.PostgreSQL.List
256−import Squeal.PostgreSQL.PG
257186import Squeal.PostgreSQL.Schema
258187
259188-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into
@@ -277,20 +206,19 @@ class ToParam (x :: Type) (pg :: PGType) where
277206 toParam :: x -> K Encoding.Encoding pg
278207instance ToParam Bool 'PGbool where toParam = K . Encoding.bool
279208instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16
209+instance ToParam Word16 'PGint2 where toParam = K . Encoding.int2_word16
280210instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32
211+instance ToParam Word32 'PGint4 where toParam = K . Encoding.int4_word32
281212instance 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
283214instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4
284215instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8
285216instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric
286−instance ToParam Money 'PGmoney where toParam = K . Encoding.int8_int64 . cents
287217instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid
288218instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet
289219instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8
290220instance ToParam Strict.Text 'PGtext where toParam = K . Encoding.text_strict
291221instance 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
294222instance ToParam Strict.ByteString 'PGbytea where
295223 toParam = K . Encoding.bytea_strict
296224instance ToParam Lazy.ByteString 'PGbytea where
@@ -304,40 +232,17 @@ instance ToParam LocalTime 'PGtimestamp where
304232instance ToParam UTCTime 'PGtimestamptz where
305233 toParam = K . Encoding.timestamptz_int
306234instance ToParam DiffTime 'PGinterval where toParam = K . Encoding.interval_int
307−instance ToParam Aeson.Value 'PGjson where toParam = K . Encoding.json_ast
308−instance ToParam Aeson.Value 'PGjsonb where toParam = K . Encoding.jsonb_ast
309−instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where
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
328− toParam = K
329− . Encoding.nullableArray_vector
330− (getOid (oidOf @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
235+instance ToParam Value 'PGjson where toParam = K . Encoding.json_ast
236+instance ToParam Value 'PGjsonb where toParam = K . Encoding.jsonb_ast
237+instance (HasOid pg, ToParam x pg)
238+ => ToParam (Vector (Maybe x)) ('PGvararray pg) where
239+ toParam = K . Encoding.nullableArray_vector
240+ (oid @pg) (unK . toParam @x @pg)
336241instance
337242 ( IsEnumType x
338243 , HasDatatypeInfo x
339− , LabelsPG x ~ labels
340− ) => ToParam (Enumerated x) ('PGenum labels) where
244+ , LabelsFrom x ~ labels
245+ ) => ToParam x ('PGenum labels) where
341246 toParam =
342247 let
343248 gshowConstructor :: NP ConstructorInfo xss -> SOP I xss -> String
@@ -348,23 +253,24 @@ instance
348253 gshowConstructor constructors (SOP xs)
349254 in
350255 K . Encoding.text_strict
351− . Strict.Text.pack
256+ . Strict.pack
352257 . gshowConstructor (constructorInfo (datatypeInfo (Proxy @x)))
353258 . from
354− . getEnumerated
355259instance
356260 ( SListI fields
357− , IsRecord x xs
358− , AllZip ToField xs fields
359− , All OidOfField fields
360− ) => ToParam (Composite x) ('PGcomposite fields) where
261+ , MapMaybes xs
262+ , IsProductType x (Maybes xs)
263+ , AllZip ToAliasedParam xs fields
264+ , FieldNamesFrom x ~ AliasesOf fields
265+ , All HasAliasedOid fields
266+ ) => ToParam x ('PGcomposite fields) where
361267 toParam =
362268 let
363269
364− encoders = htrans (Proxy @ToField) toField
270+ encoders = htrans (Proxy @ToAliasedParam) toAliasedParam
365271
366272 composite
367− :: All OidOfField row
273+ :: All HasAliasedOid row
368274 => NP (K (Maybe Encoding.Encoding)) row
369275 -> K Encoding.Encoding ('PGcomposite row)
370276 composite fields = K $
@@ -381,179 +287,53 @@ instance
381287 int32BE (fromIntegral (lengthSList (Proxy @xs))) <>
382288 let
383289 each
384− :: OidOfField field
290+ :: HasAliasedOid field
385291 => K (Maybe Encoding.Encoding) field
386292 -> Encoding.Encoding
387293 each (K field :: K (Maybe Encoding.Encoding) field) =
388− word32BE (getOid (oidOfField @field))
294+ word32BE (aliasedOid @field)
389295 <> case field of
390296 Nothing -> int64BE (-1)
391297 Just value ->
392298 int32BE (fromIntegral (builderLength value))
393299 <> value
394300 in
395− hcfoldMap (Proxy @OidOfField) each fields
301+ hcfoldMap (Proxy @HasAliasedOid) each fields
396302
397303 in
398− composite . encoders . toRecord . getComposite
399−
400−-- | The object identifier of a `PGType`.
401−--
402−-- >>> :set -XTypeApplications
403−-- >>> oidOf @'PGbool
404−-- Oid 16
405−class OidOf (ty :: PGType) where oidOf :: LibPQ.Oid
406−instance OidOf 'PGbool where oidOf = LibPQ.Oid 16
407−instance OidOf ('PGfixarray ns (null 'PGbool)) where oidOf = LibPQ.Oid 1000
408−instance OidOf ('PGvararray (null 'PGbool)) where oidOf = LibPQ.Oid 1000
409−instance OidOf 'PGint2 where oidOf = LibPQ.Oid 21
410−instance OidOf ('PGfixarray ns (null 'PGint2)) where oidOf = LibPQ.Oid 1005
411−instance OidOf ('PGvararray (null 'PGint2)) where oidOf = LibPQ.Oid 1005
412−instance OidOf 'PGint4 where oidOf = LibPQ.Oid 23
413−instance OidOf ('PGfixarray ns (null 'PGint4)) where oidOf = LibPQ.Oid 1007
414−instance OidOf ('PGvararray (null 'PGint4)) where oidOf = LibPQ.Oid 1007
415−instance OidOf 'PGint8 where oidOf = LibPQ.Oid 20
416−instance OidOf ('PGfixarray ns (null 'PGint8)) where oidOf = LibPQ.Oid 1016
417−instance OidOf ('PGvararray (null 'PGint8)) where oidOf = LibPQ.Oid 1016
418−instance OidOf 'PGnumeric where oidOf = LibPQ.Oid 1700
419−instance OidOf ('PGfixarray ns (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231
420−instance OidOf ('PGvararray (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231
421−instance OidOf 'PGfloat4 where oidOf = LibPQ.Oid 700
422−instance OidOf ('PGfixarray ns (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021
423−instance OidOf ('PGvararray (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021
424−instance OidOf 'PGfloat8 where oidOf = LibPQ.Oid 701
425−instance OidOf ('PGfixarray ns (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022
426−instance OidOf ('PGvararray (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022
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
304+ composite . encoders . unMaybes . unZ . unSOP . from
305+
306+class HasAliasedOid (field :: (Symbol, PGType)) where aliasedOid :: Word32
307+instance HasOid ty => HasAliasedOid (alias ::: ty) where aliasedOid = oid @ty
308+
309+class ToAliasedParam (x :: Type) (field :: (Symbol, PGType)) where
310+ toAliasedParam :: Maybe x -> K (Maybe Encoding.Encoding) field
311+instance ToParam x ty => ToAliasedParam x (alias ::: ty) where
312+ toAliasedParam = \case
313+ Nothing -> K Nothing
314+ Just x -> K . Just . unK $ toParam @x @ty x
315+
316+-- | A `ToColumnParam` constraint lifts the `ToParam` encoding
317+-- of a `Type` to a `NullityType`, encoding `Maybe`s to `Null`s. You should
318+-- not define instances of `ToColumnParam`, just use the provided instances.
319+class ToColumnParam (x :: Type) (ty :: NullityType) where
320+ -- | >>> toColumnParam @Int16 @('NotNull 'PGint2) 0
321+ -- K (Just "\NUL\NUL")
322+ --
323+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) (Just 0)
324+ -- K (Just "\NUL\NUL")
325+ --
326+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) Nothing
327+ -- K Nothing
328+ toColumnParam :: x -> K (Maybe Strict.ByteString) ty
329+instance ToParam x pg => ToColumnParam x ('NotNull pg) where
330+ toColumnParam = K . Just . Encoding.encodingBytes . unK . toParam @x @pg
331+instance ToParam x pg => ToColumnParam (Maybe x) ('Null pg) where
332+ toColumnParam = K . fmap (Encoding.encodingBytes . unK . toParam @x @pg)
553333
554334-- | A `ToParams` constraint generically sequences the encodings of `Type`s
555335-- 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
557337-- which in turn provide `ToParams` instances.
558338class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where
559339 -- | >>> type Params = '[ 'NotNull 'PGbool, 'Null 'PGint2]
@@ -565,98 +345,61 @@ class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where
565345 -- >>> instance Generic Tuple
566346 -- >>> toParams @Tuple @Params (Tuple False (Just 0))
567347 -- K (Just "\NUL") :* K (Just "\NUL\NUL") :* Nil
568− toParams :: x -> NP (K (Maybe Encoding.Encoding)) tys
569−instance (SListI tys, IsProductType x xs, AllZip ToNullityParam xs tys)
348+ toParams :: x -> NP (K (Maybe Strict.ByteString)) tys
349+instance (SListI tys, IsProductType x xs, AllZip ToColumnParam xs tys)
570350 => ToParams x tys where
571351 toParams
572− = htrans (Proxy @ToNullityParam) (toNullityParam . unI)
352+ = htrans (Proxy @ToColumnParam) (toColumnParam . unI)
573353 . unZ . unSOP . from
574354
575355-- | A `FromValue` constraint gives a parser from the binary format of
576356-- a PostgreSQL `PGType` into a Haskell `Type`.
577357class FromValue (pg :: PGType) (y :: Type) where
578358 -- | >>> newtype Id = Id { getId :: Int16 } deriving Show
579− -- >>> instance FromValue 'PGint2 Id where fromValue = Id <$> fromValue @'PGint2
580− fromValue :: Decoding.Value y
581−instance FromValue 'PGbool Bool where fromValue = Decoding.bool
582−instance FromValue 'PGint2 Int16 where fromValue = Decoding.int
583−instance FromValue 'PGint4 Int32 where fromValue = Decoding.int
584−instance FromValue 'PGint8 Int64 where fromValue = Decoding.int
585−instance FromValue 'PGoid Word32 where fromValue = Decoding.int
586−instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4
587−instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8
588−instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric
589−instance FromValue 'PGmoney Money where fromValue = Money <$> Decoding.int
590−instance FromValue 'PGuuid UUID where fromValue = Decoding.uuid
591−instance FromValue 'PGinet (NetAddr IP) where fromValue = Decoding.inet
592−instance FromValue ('PGchar 1) Char where fromValue = Decoding.char
593−instance FromValue 'PGtext Strict.Text where fromValue = Decoding.text_strict
594−instance FromValue 'PGtext Lazy.Text where fromValue = Decoding.text_lazy
595−instance FromValue 'PGtext String where
596− fromValue = Strict.Text.unpack <$> Decoding.text_strict
359+ -- >>> instance FromValue 'PGint2 Id where fromValue = fmap Id . fromValue
360+ fromValue :: proxy pg -> Decoding.Value y
361+instance FromValue 'PGbool Bool where fromValue _ = Decoding.bool
362+instance FromValue 'PGint2 Int16 where fromValue _ = Decoding.int
363+instance FromValue 'PGint4 Int32 where fromValue _ = Decoding.int
364+instance FromValue 'PGint8 Int64 where fromValue _ = Decoding.int
365+instance FromValue 'PGfloat4 Float where fromValue _ = Decoding.float4
366+instance FromValue 'PGfloat8 Double where fromValue _ = Decoding.float8
367+instance FromValue 'PGnumeric Scientific where fromValue _ = Decoding.numeric
368+instance FromValue 'PGuuid UUID where fromValue _ = Decoding.uuid
369+instance FromValue 'PGinet (NetAddr IP) where fromValue _ = Decoding.inet
370+instance FromValue ('PGchar 1) Char where fromValue _ = Decoding.char
371+instance FromValue 'PGtext Strict.Text where fromValue _ = Decoding.text_strict
372+instance FromValue 'PGtext Lazy.Text where fromValue _ = Decoding.text_lazy
597373instance FromValue 'PGbytea Strict.ByteString where
598− fromValue = Decoding.bytea_strict
374+ fromValue _ = Decoding.bytea_strict
599375instance FromValue 'PGbytea Lazy.ByteString where
600− fromValue = Decoding.bytea_lazy
601−instance FromValue 'PGdate Day where fromValue = Decoding.date
602−instance FromValue 'PGtime TimeOfDay where fromValue = Decoding.time_int
376+ fromValue _ = Decoding.bytea_lazy
377+instance FromValue 'PGdate Day where fromValue _ = Decoding.date
378+instance FromValue 'PGtime TimeOfDay where fromValue _ = Decoding.time_int
603379instance FromValue 'PGtimetz (TimeOfDay, TimeZone) where
604− fromValue = Decoding.timetz_int
380+ fromValue _ = Decoding.timetz_int
605381instance FromValue 'PGtimestamp LocalTime where
606− fromValue = Decoding.timestamp_int
382+ fromValue _ = Decoding.timestamp_int
607383instance FromValue 'PGtimestamptz UTCTime where
608− fromValue = Decoding.timestamptz_int
384+ fromValue _ = Decoding.timestamptz_int
609385instance FromValue 'PGinterval DiffTime where
610− fromValue = Decoding.interval_int
611−instance FromValue 'PGjson Aeson.Value where fromValue = Decoding.json_ast
612−instance FromValue 'PGjsonb Aeson.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 <$>
618− Decoding.jsonb_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)
619−instance FromValue pg y
620− => FromValue ('PGvararray ('NotNull pg)) (VarArray (Vector y)) where
621− fromValue =
622− let
623− rep n x = VarArray <$> Vector.replicateM n x
624− in
625− Decoding.array $ Decoding.dimensionArray rep
626− (fromFixArray @'[] @('NotNull 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
653− fromValue = FixArray <$> Decoding.array (fromFixArray @dims @ty @y)
386+ fromValue _ = Decoding.interval_int
387+instance FromValue 'PGjson Value where fromValue _ = Decoding.json_ast
388+instance FromValue 'PGjsonb Value where fromValue _ = Decoding.jsonb_ast
389+instance FromValue pg y => FromValue ('PGvararray pg) (Vector (Maybe y)) where
390+ fromValue _ = Decoding.array
391+ (Decoding.dimensionArray Vector.replicateM
392+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))
393+instance FromValue pg y => FromValue ('PGfixarray n pg) (Vector (Maybe y)) where
394+ fromValue _ = Decoding.array
395+ (Decoding.dimensionArray Vector.replicateM
396+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))
654397instance
655398 ( IsEnumType y
656399 , HasDatatypeInfo y
657− , LabelsPG y ~ labels
658− ) => FromValue ('PGenum labels) (Enumerated y) where
659− fromValue =
400+ , LabelsFrom y ~ labels
401+ ) => FromValue ('PGenum labels) y where
402+ fromValue _ =
660403 let
661404 greadConstructor
662405 :: All ((~) '[]) xss
@@ -669,16 +412,29 @@ instance
669412 then Just (SOP (Z Nil))
670413 else SOP . S . unSOP <$> greadConstructor constructors name
671414 in
672− fmap Enumerated
673− . Decoding.enum
415+ Decoding.enum
674416 $ fmap to
675417 . greadConstructor (constructorInfo (datatypeInfo (Proxy @y)))
676− . Strict.Text.unpack
418+ . Strict.unpack
419+
677420instance
678− ( FromRow fields y
679− ) => FromValue ('PGcomposite fields) (Composite y) where
421+ ( SListI fields
422+ , MapMaybes ys
423+ , IsProductType y (Maybes ys)
424+ , AllZip FromAliasedValue fields ys
425+ , FieldNamesFrom y ~ AliasesOf fields
426+ ) => FromValue ('PGcomposite fields) y where
680427 fromValue =
681428 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
682438 -- <number of fields: 4 bytes>
683439 -- [for each field]
684440 -- <OID of field's type: sizeof(Oid) bytes>
@@ -689,133 +445,80 @@ instance
689445 -- <value: <length> bytes>
690446 -- [end if]
691447 -- [end for]
692− composite = Decoding.valueParser $ do
693448 unitOfSize 4
694− hsequence' $ hpure $ Comp $ do
695− unitOfSize 4
696− len <- sized 4 Decoding.int
697− if len == -1
698− then return (K Nothing)
699− else K . Just <$> bytesOfSize len
700− in
701− fmap Composite (Decoding.fn (fromRow @fields <=< composite))
449+ let
450+ each field = do
451+ unitOfSize 4
452+ len <- sized 4 Decoding.int
453+ if len == -1 then return Nothing else Just <$> sized len field
454+ htraverse' each fields
455+
456+ in fmap (to . SOP . Z . maybes) . composite . decoders
702457
703−-- | A `FromField` constraint lifts the `FromValue` parser
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+
463+-- | A `FromColumnValue` constraint lifts the `FromValue` parser
704464-- to a decoding of a @(Symbol, NullityType)@ to a `Type`,
705465-- decoding `Null`s to `Maybe`s. You should not define instances for
706−-- `FromField`, just use the provided instances.
707−class FromField (pg :: (Symbol, NullityType)) (y :: (Symbol, Type)) where
708− fromField
709− :: K (Maybe Strict.ByteString) pg
710− -> (Either Strict.Text :.: P) y
466+-- `FromColumnValue`, just use the provided instances.
467+class FromColumnValue (colty :: (Symbol,NullityType)) (y :: Type) where
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})
476+ fromColumnValue :: K (Maybe Strict.ByteString) colty -> y
711477instance FromValue pg y
712− => FromField (column ::: ('NotNull pg)) (column ::: y) where
713− fromField = Comp . \case
714− K Nothing -> Left "fromField: saw NULL when expecting NOT NULL"
715− K (Just bytestring) -> P <$>
716− Decoding.valueParser (fromValue @pg) bytestring
478+ => FromColumnValue (column ::: ('NotNull pg)) y where
479+ fromColumnValue = \case
480+ K Nothing -> error "fromColumnValue: saw NULL when expecting NOT NULL"
481+ K (Just bs) ->
482+ let
483+ errOrValue =
484+ Decoding.valueParser (fromValue @pg @y Proxy) bs
485+ err str = error $ "fromColumnValue: " ++ Strict.unpack str
486+ in
487+ either err id errOrValue
717488instance FromValue pg y
718− => FromField (column ::: 'Null pg) (column ::: Maybe y) where
719− fromField = Comp . \case
720− K Nothing -> Right $ P Nothing
721− K (Just bytestring) -> P . Just <$>
722− Decoding.valueParser (fromValue @pg) bytestring
723−
724−-- | A `FromFixArray` constraint gives a decoding to a Haskell `Type`
725−-- from the binary format of a PostgreSQL fixed-length array.
726−-- You should not define instances for
727−-- `FromFixArray`, just use the provided instances.
728−class FromFixArray (dims :: [Nat]) (ty :: NullityType) (y :: Type) where
729− fromFixArray :: Decoding.Array y
730−instance FromValue pg y => FromFixArray '[] ('NotNull pg) y where
731− fromFixArray = Decoding.valueArray (fromValue @pg @y)
732−instance FromValue pg y => FromFixArray '[] ('Null pg) (Maybe y) where
733− fromFixArray = Decoding.nullableValueArray (fromValue @pg @y)
734−instance
735− ( IsProductType product ys
736− , Length ys ~ dim
737− , All ((~) y) ys
738− , FromFixArray dims ty y )
739− => FromFixArray (dim ': dims) ty product where
740− fromFixArray =
741− let
742− rep _ = fmap (to . SOP . Z) . replicateMN
743− in
744− Decoding.dimensionArray rep (fromFixArray @dims @ty @y)
489+ => FromColumnValue (column ::: ('Null pg)) (Maybe y) where
490+ fromColumnValue (K nullOrBytes)
491+ = either err id
492+ . Decoding.valueParser (fromValue @pg @y Proxy)
493+ <$> nullOrBytes
494+ where
495+ err str = error $ "fromColumnValue: " ++ Strict.unpack str
745496
746497-- | 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
748499-- 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
750501-- provide `FromRow` instances.
751−class SListI result => FromRow (result :: RowType) y where
502+class SListI results => FromRow (results :: RelationType) y where
752503 -- | >>> :set -XOverloadedStrings
753504 -- >>> import Data.Text
754505 -- >>> newtype UserId = UserId { getUserId :: Int16 } deriving Show
755− -- >>> instance FromValue 'PGint2 UserId where fromValue = UserId <$> fromValue @'PGint2
506+ -- >>> instance FromValue 'PGint2 UserId where fromValue = fmap UserId . fromValue
756507 -- >>> data UserRow = UserRow { userId :: UserId, userName :: Maybe Text } deriving (Show, GHC.Generic)
757508 -- >>> instance Generic UserRow
758509 -- >>> instance HasDatatypeInfo UserRow
759510 -- >>> type User = '["userId" ::: 'NotNull 'PGint2, "userName" ::: 'Null 'PGtext]
760511 -- >>> fromRow @User @UserRow (K (Just "\NUL\SOH") :* K (Just "bloodninja") :* Nil)
761− -- Right (UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"})
762− fromRow :: NP (K (Maybe Strict.ByteString)) result -> Either Strict.Text y
512+ -- UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"}
513+ fromRow :: NP (K (Maybe Strict.ByteString)) results -> y
763514instance
764− ( SListI result
765− , IsRecord y ys
766− , AllZip FromField result ys
767− ) => FromRow result y where
515+ ( SListI results
516+ , IsProductType y ys
517+ , AllZip FromColumnValue results ys
518+ , FieldNamesFrom y ~ AliasesOf results
519+ ) => FromRow results y where
768520 fromRow
769− = fmap fromRecord
770− . hsequence'
771− . htrans (Proxy @FromField) fromField
772−------------------------------------------------------
773−-- P records
774−------------------------------------------------------
775−-- instance (FromField (col ::: pg) (col ::: hask))
776−-- => FromRow '[col ::: pg] (P (col ::: hask)) where
777−-- fromRow (pg :* Nil) = (unComp . fromField) pg
778−-- instance
779−-- ( row ~ Join row1 row2
780−-- , FromRow row1 hask1
781−-- , FromRow row2 hask2
782−-- , SListI row
783−-- ) => FromRow row (hask1, hask2) where
784−-- fromRow row = case disjoin @row1 @row2 row of
785−-- (row1, row2) -> (,) <$> 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)
521+ = to . SOP . Z . htrans (Proxy @FromColumnValue) (I . fromColumnValue)
819522
820523-- | `Only` is a 1-tuple type, useful for encoding a single parameter with
821524-- `toParams` or decoding a single value with `fromRow`.
@@ -825,24 +528,8 @@ instance
825528-- K (Just "foo") :* Nil
826529--
827530-- >>> fromRow @'["fromOnly" ::: 'Null 'PGtext] @(Only (Maybe Text)) (K (Just "bar") :* Nil)
828−-- Right (Only {fromOnly = Just "bar"})
531+-- Only {fromOnly = Just "bar"}
829532newtype Only x = Only { fromOnly :: x }
830533 deriving (Functor,Foldable,Traversable,Eq,Ord,Read,Show,GHC.Generic)
831534instance Generic (Only x)
832535instance 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+918−23
@@ -11,15 +11,13 @@ Squeal data definition language.
1111{-# LANGUAGE
1212 AllowAmbiguousTypes
1313 , ConstraintKinds
14− , DeriveAnyClass
1514 , DeriveGeneric
16− , DerivingStrategies
1715 , FlexibleContexts
1816 , FlexibleInstances
1917 , GADTs
18+ , GeneralizedNewtypeDeriving
2019 , LambdaCase
2120 , MultiParamTypeClasses
22− , OverloadedLabels
2321 , OverloadedStrings
2422 , RankNTypes
2523 , ScopedTypeVariables
@@ -27,56 +25,953 @@ Squeal data definition language.
2725 , TypeInType
2826 , TypeOperators
2927 , UndecidableSuperClasses
30− , UndecidableInstances
3128#-}
3229
3330module Squeal.PostgreSQL.Definition
3431 ( -- * Definition
35− Definition (..)
32+ Definition (UnsafeDefinition, renderDefinition)
3633 , (>>>)
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
3886 ) where
3987
4088import Control.Category
4189import Control.DeepSeq
4290import Data.ByteString
4391import Data.Monoid
92+import GHC.TypeLits
4493import Prelude hiding ((.), id)
4594
95+import qualified Generics.SOP as SOP
4696import qualified GHC.Generics as GHC
4797
48−import Squeal.PostgreSQL.Manipulation
98+import Squeal.PostgreSQL.Expression
99+import Squeal.PostgreSQL.Query
49100import Squeal.PostgreSQL.Render
50101import Squeal.PostgreSQL.Schema
51102
52−-- $setup
53−-- >>> import Squeal.PostgreSQL
54−
55103{-----------------------------------------
56104statements
57105-----------------------------------------}
58106
59−-- | A `Definition` is a statement that changes the schemas of the
107+-- | A `Definition` is a statement that changes the schema of the
60108-- database, like a `createTable`, `dropTable`, or `alterTable` command.
61109-- `Definition`s may be composed using the `>>>` operator.
62110newtype Definition
63− (schemas0 :: SchemasType)
64− (schemas1 :: SchemasType)
111+ (schema0 :: SchemaType)
112+ (schema1 :: SchemaType)
65113 = UnsafeDefinition { renderDefinition :: ByteString }
66114 deriving (GHC.Generic,Show,Eq,Ord,NFData)
67115
68−instance RenderSQL (Definition schemas0 schemas1) where
116+instance RenderSQL (Definition schema0 schema1) where
69117 renderSQL = renderDefinition
70118
71119instance Category Definition where
72120 id = UnsafeDefinition ";"
73121 ddl1 . ddl0 = UnsafeDefinition $
74− renderSQL ddl0 <> "\n" <> renderSQL ddl1
75−
76−-- | A `Manipulation` without input or output can be run as a statement
77−-- along with other `Definition`s, by embedding it using `manipDefinition`.
78−manipDefinition
79− :: Manipulation '[] schemas '[] '[]
80− -- ^ no input or output
81− -> Definition schemas schemas
82−manipDefinition = UnsafeDefinition . (<> ";") . renderSQL
122+ renderDefinition ddl0 <> "\n" <> renderDefinition ddl1
123+
124+{-----------------------------------------
125+CREATE statements
126+-----------------------------------------}
127+
128+{- | `createTable` adds a table to the schema.
129+
130+>>> :set -XOverloadedLabels
131+>>> :{
132+type Table = '[] :=>
133+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4
134+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
135+:}
136+
137+>>> :{
138+let
139+ setup :: Definition '[] '["tab" ::: 'Table Table]
140+ setup = createTable #tab
141+ (nullable int `as` #a :* nullable real `as` #b) Nil
142+in printSQL setup
143+:}
144+CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
145+-}
146+createTable
147+ :: ( KnownSymbol table
148+ , columns ~ (col ': cols)
149+ , SOP.SListI columns
150+ , SOP.SListI constraints
151+ , schema1 ~ Create table ('Table (constraints :=> columns)) schema0 )
152+ => Alias table -- ^ the name of the table to add
153+ -> NP (Aliased (ColumnTypeExpression schema0)) columns
154+ -- ^ the names and datatype of each column
155+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints
156+ -- ^ constraints that must hold for the table
157+ -> Definition schema0 schema1
158+createTable tab columns constraints = UnsafeDefinition $
159+ "CREATE TABLE" <+> renderCreation tab columns constraints
160+
161+{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.
162+Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.
163+`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in
164+the `Category` of `Definition`s.
165+
166+>>> :set -XOverloadedLabels -XTypeApplications
167+>>> :{
168+type Table = '[] :=>
169+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4
170+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
171+:}
172+
173+>>> type Schema = '["tab" ::: 'Table Table]
174+
175+>>> :{
176+let
177+ setup :: Definition Schema Schema
178+ setup = createTableIfNotExists #tab
179+ (nullable int `as` #a :* nullable real `as` #b) Nil
180+in printSQL setup
181+:}
182+CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);
183+-}
184+createTableIfNotExists
185+ :: ( Has table schema ('Table (constraints :=> columns))
186+ , SOP.SListI columns
187+ , SOP.SListI constraints )
188+ => Alias table -- ^ the name of the table to add
189+ -> NP (Aliased (ColumnTypeExpression schema)) columns
190+ -- ^ the names and datatype of each column
191+ -> NP (Aliased (TableConstraintExpression schema table)) constraints
192+ -- ^ constraints that must hold for the table
193+ -> Definition schema schema
194+createTableIfNotExists tab columns constraints = UnsafeDefinition $
195+ "CREATE TABLE IF NOT EXISTS"
196+ <+> renderCreation tab columns constraints
197+
198+-- helper function for `createTable` and `createTableIfNotExists`
199+renderCreation
200+ :: ( KnownSymbol table
201+ , SOP.SListI columns
202+ , SOP.SListI constraints )
203+ => Alias table -- ^ the name of the table to add
204+ -> NP (Aliased (ColumnTypeExpression schema0)) columns
205+ -- ^ the names and datatype of each column
206+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints
207+ -- ^ constraints that must hold for the table
208+ -> ByteString
209+renderCreation tab columns constraints = renderAlias tab
210+ <+> parenthesized
211+ ( renderCommaSeparated renderColumnDef columns
212+ <> ( case constraints of
213+ Nil -> ""
214+ _ -> ", " <>
215+ renderCommaSeparated renderConstraint constraints ) )
216+ <> ";"
217+ where
218+ renderColumnDef :: Aliased (ColumnTypeExpression schema) x -> ByteString
219+ renderColumnDef (ty `As` column) =
220+ renderAlias column <+> renderColumnTypeExpression ty
221+ renderConstraint
222+ :: Aliased (TableConstraintExpression schema columns) constraint
223+ -> ByteString
224+ renderConstraint (constraint `As` alias) =
225+ "CONSTRAINT" <+> renderAlias alias <+> renderTableConstraintExpression constraint
226+
227+-- | Data types are a way to limit the kind of data that can be stored in a
228+-- table. For many applications, however, the constraint they provide is
229+-- too coarse. For example, a column containing a product price should
230+-- probably only accept positive values. But there is no standard data type
231+-- that accepts only positive numbers. Another issue is that you might want
232+-- to constrain column data with respect to other columns or rows.
233+-- For example, in a table containing product information,
234+-- there should be only one row for each product number.
235+-- `TableConstraint`s give you as much control over the data in your tables
236+-- as you wish. If a user attempts to store data in a column that would
237+-- violate a constraint, an error is raised. This applies
238+-- even if the value came from the default value definition.
239+newtype TableConstraintExpression
240+ (schema :: SchemaType)
241+ (table :: Symbol)
242+ (tableConstraint :: TableConstraint)
243+ = UnsafeTableConstraintExpression
244+ { renderTableConstraintExpression :: ByteString }
245+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
246+
247+{-| A `check` constraint is the most generic `TableConstraint` type.
248+It allows you to specify that the value in a certain column must satisfy
249+a Boolean (truth-value) expression.
250+
251+>>> :{
252+type Schema = '[
253+ "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[
254+ "a" ::: 'NoDef :=> 'NotNull 'PGint4,
255+ "b" ::: 'NoDef :=> 'NotNull 'PGint4
256+ ])]
257+:}
258+
259+>>> :{
260+let
261+ definition :: Definition '[] Schema
262+ definition = createTable #tab
263+ ( (int & notNullable) `as` #a :*
264+ (int & notNullable) `as` #b )
265+ ( check (#a :* #b) (#a .> #b) `as` #inequality )
266+:}
267+
268+>>> printSQL definition
269+CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));
270+-}
271+check
272+ :: ( Has alias schema ('Table table)
273+ , HasAll aliases (TableToRelation table) subcolumns )
274+ => NP Alias aliases
275+ -- ^ specify the subcolumns which are getting checked
276+ -> (forall tab. Condition schema '[tab ::: subcolumns] 'Ungrouped '[])
277+ -- ^ a closed `Condition` on those subcolumns
278+ -> TableConstraintExpression schema alias ('Check aliases)
279+check _cols condition = UnsafeTableConstraintExpression $
280+ "CHECK" <+> parenthesized (renderExpression condition)
281+
282+{-| A `unique` constraint ensure that the data contained in a column,
283+or a group of columns, is unique among all the rows in the table.
284+
285+>>> :{
286+type Schema = '[
287+ "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[
288+ "a" ::: 'NoDef :=> 'Null 'PGint4,
289+ "b" ::: 'NoDef :=> 'Null 'PGint4
290+ ])]
291+:}
292+
293+>>> :{
294+let
295+ definition :: Definition '[] Schema
296+ definition = createTable #tab
297+ ( (int & nullable) `as` #a :*
298+ (int & nullable) `as` #b )
299+ ( unique (#a :* #b) `as` #uq_a_b )
300+:}
301+
302+>>> printSQL definition
303+CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));
304+-}
305+unique
306+ :: ( Has alias schema ('Table table)
307+ , HasAll aliases (TableToRelation table) subcolumns )
308+ => NP Alias aliases
309+ -- ^ specify subcolumns which together are unique for each row
310+ -> TableConstraintExpression schema alias ('Unique aliases)
311+unique columns = UnsafeTableConstraintExpression $
312+ "UNIQUE" <+> parenthesized (commaSeparated (renderAliases columns))
313+
314+{-| A `primaryKey` constraint indicates that a column, or group of columns,
315+can be used as a unique identifier for rows in the table.
316+This requires that the values be both unique and not null.
317+
318+>>> :{
319+type Schema = '[
320+ "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[
321+ "id" ::: 'Def :=> 'NotNull 'PGint4,
322+ "name" ::: 'NoDef :=> 'NotNull 'PGtext
323+ ])]
324+:}
325+
326+>>> :{
327+let
328+ definition :: Definition '[] Schema
329+ definition = createTable #tab
330+ ( serial `as` #id :*
331+ (text & notNullable) `as` #name )
332+ ( primaryKey #id `as` #pk_id )
333+:}
334+
335+>>> printSQL definition
336+CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));
337+-}
338+primaryKey
339+ :: ( Has alias schema ('Table table)
340+ , HasAll aliases (TableToColumns table) subcolumns
341+ , AllNotNull subcolumns )
342+ => NP Alias aliases
343+ -- ^ specify the subcolumns which together form a primary key.
344+ -> TableConstraintExpression schema alias ('PrimaryKey aliases)
345+primaryKey columns = UnsafeTableConstraintExpression $
346+ "PRIMARY KEY" <+> parenthesized (commaSeparated (renderAliases columns))
347+
348+{-| A `foreignKey` specifies that the values in a column
349+(or a group of columns) must match the values appearing in some row of
350+another table. We say this maintains the referential integrity
351+between two related tables.
352+
353+>>> :{
354+type Schema =
355+ '[ "users" ::: 'Table (
356+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
357+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
358+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
359+ ])
360+ , "emails" ::: 'Table (
361+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
362+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
363+ ] :=>
364+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
365+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
366+ , "email" ::: 'NoDef :=> 'Null 'PGtext
367+ ])
368+ ]
369+:}
370+
371+>>> :{
372+let
373+ setup :: Definition '[] Schema
374+ setup =
375+ createTable #users
376+ ( serial `as` #id :*
377+ (text & notNullable) `as` #name )
378+ ( primaryKey #id `as` #pk_users ) >>>
379+ createTable #emails
380+ ( serial `as` #id :*
381+ (int & notNullable) `as` #user_id :*
382+ (text & nullable) `as` #email )
383+ ( primaryKey #id `as` #pk_emails :*
384+ foreignKey #user_id #users #id
385+ OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
386+in printSQL setup
387+:}
388+CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
389+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);
390+
391+A `foreignKey` can even be a table self-reference.
392+
393+>>> :{
394+type Schema =
395+ '[ "employees" ::: 'Table (
396+ '[ "employees_pk" ::: 'PrimaryKey '["id"]
397+ , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]
398+ ] :=>
399+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
400+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
401+ , "employer_id" ::: 'NoDef :=> 'Null 'PGint4
402+ ])
403+ ]
404+:}
405+
406+>>> :{
407+let
408+ setup :: Definition '[] Schema
409+ setup =
410+ createTable #employees
411+ ( serial `as` #id :*
412+ (text & notNullable) `as` #name :*
413+ (integer & nullable) `as` #employer_id )
414+ ( primaryKey #id `as` #employees_pk :*
415+ foreignKey #employer_id #employees #id
416+ OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )
417+in printSQL setup
418+:}
419+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);
420+-}
421+foreignKey
422+ :: (ForeignKeyed schema child parent
423+ table reftable
424+ columns refcolumns
425+ constraints cols
426+ reftys tys )
427+ => NP Alias columns
428+ -- ^ column or columns in the table
429+ -> Alias parent
430+ -- ^ reference table
431+ -> NP Alias refcolumns
432+ -- ^ reference column or columns in the reference table
433+ -> OnDeleteClause
434+ -- ^ what to do when reference is deleted
435+ -> OnUpdateClause
436+ -- ^ what to do when reference is updated
437+ -> TableConstraintExpression schema child
438+ ('ForeignKey columns parent refcolumns)
439+foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $
440+ "FOREIGN KEY" <+> parenthesized (commaSeparated (renderAliases keys))
441+ <+> "REFERENCES" <+> renderAlias parent
442+ <+> parenthesized (commaSeparated (renderAliases refs))
443+ <+> renderOnDeleteClause ondel
444+ <+> renderOnUpdateClause onupd
445+
446+-- | A constraint synonym between types involved in a foreign key constraint.
447+type ForeignKeyed schema
448+ child parent
449+ table reftable
450+ columns refcolumns
451+ constraints cols
452+ reftys tys =
453+ ( Has child schema ('Table table)
454+ , Has parent schema ('Table reftable)
455+ , HasAll columns (TableToColumns table) tys
456+ , reftable ~ (constraints :=> cols)
457+ , HasAll refcolumns cols reftys
458+ , SOP.AllZip SamePGType tys reftys
459+ , Uniquely refcolumns constraints )
460+
461+-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.
462+data OnDeleteClause
463+ = OnDeleteNoAction
464+ -- ^ if any referencing rows still exist when the constraint is checked,
465+ -- an error is raised
466+ | OnDeleteRestrict -- ^ prevents deletion of a referenced row
467+ | OnDeleteCascade
468+ -- ^ specifies that when a referenced row is deleted,
469+ -- row(s) referencing it should be automatically deleted as well
470+ deriving (GHC.Generic,Show,Eq,Ord)
471+instance NFData OnDeleteClause
472+
473+-- | Render `OnDeleteClause`.
474+renderOnDeleteClause :: OnDeleteClause -> ByteString
475+renderOnDeleteClause = \case
476+ OnDeleteNoAction -> "ON DELETE NO ACTION"
477+ OnDeleteRestrict -> "ON DELETE RESTRICT"
478+ OnDeleteCascade -> "ON DELETE CASCADE"
479+
480+-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked
481+-- when a referenced column is changed (updated).
482+data OnUpdateClause
483+ = OnUpdateNoAction
484+ -- ^ if any referencing rows has not changed when the constraint is checked,
485+ -- an error is raised
486+ | OnUpdateRestrict -- ^ prevents update of a referenced row
487+ | OnUpdateCascade
488+ -- ^ the updated values of the referenced column(s) should be copied
489+ -- into the referencing row(s)
490+ deriving (GHC.Generic,Show,Eq,Ord)
491+instance NFData OnUpdateClause
492+
493+-- | Render `OnUpdateClause`.
494+renderOnUpdateClause :: OnUpdateClause -> ByteString
495+renderOnUpdateClause = \case
496+ OnUpdateNoAction -> "ON UPDATE NO ACTION"
497+ OnUpdateRestrict -> "ON UPDATE RESTRICT"
498+ OnUpdateCascade -> "ON UPDATE CASCADE"
499+
500+{-----------------------------------------
501+DROP statements
502+-----------------------------------------}
503+
504+-- | `dropTable` removes a table from the schema.
505+--
506+-- >>> :{
507+-- let
508+-- definition :: Definition '["muh_table" ::: 'Table t] '[]
509+-- definition = dropTable #muh_table
510+-- :}
511+--
512+-- >>> printSQL definition
513+-- DROP TABLE "muh_table";
514+dropTable
515+ :: Has table schema ('Table t)
516+ => Alias table -- ^ table to remove
517+ -> Definition schema (Drop table schema)
518+dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderAlias tab <> ";"
519+
520+{-----------------------------------------
521+ALTER statements
522+-----------------------------------------}
523+
524+-- | `alterTable` changes the definition of a table from the schema.
525+alterTable
526+ :: KnownSymbol alias
527+ => Alias alias -- ^ table to alter
528+ -> AlterTable alias table schema -- ^ alteration to perform
529+ -> Definition schema (Alter alias ('Table table) schema)
530+alterTable tab alteration = UnsafeDefinition $
531+ "ALTER TABLE"
532+ <+> renderAlias tab
533+ <+> renderAlterTable alteration
534+ <> ";"
535+
536+-- | `alterTableRename` changes the name of a table from the schema.
537+--
538+-- >>> printSQL $ alterTableRename #foo #bar
539+-- ALTER TABLE "foo" RENAME TO "bar";
540+alterTableRename
541+ :: (KnownSymbol table0, KnownSymbol table1)
542+ => Alias table0 -- ^ table to rename
543+ -> Alias table1 -- ^ what to rename it
544+ -> Definition schema (Rename table0 table1 schema)
545+alterTableRename table0 table1 = UnsafeDefinition $
546+ "ALTER TABLE" <+> renderAlias table0
547+ <+> "RENAME TO" <+> renderAlias table1 <> ";"
548+
549+-- | An `AlterTable` describes the alteration to perform on the columns
550+-- of a table.
551+newtype AlterTable
552+ (alias :: Symbol)
553+ (table :: TableType)
554+ (schema :: SchemaType) =
555+ UnsafeAlterTable {renderAlterTable :: ByteString}
556+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
557+
558+-- | An `addConstraint` adds a table constraint.
559+--
560+-- >>> :{
561+-- let
562+-- definition :: Definition
563+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
564+-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
565+-- definition = alterTable #tab (addConstraint #positive (check #col (#col .> 0)))
566+-- in printSQL definition
567+-- :}
568+-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));
569+addConstraint
570+ :: ( KnownSymbol alias
571+ , Has tab schema ('Table table0)
572+ , table0 ~ (constraints :=> columns)
573+ , table1 ~ (Create alias constraint constraints :=> columns) )
574+ => Alias alias
575+ -> TableConstraintExpression schema tab constraint
576+ -- ^ constraint to add
577+ -> AlterTable tab table1 schema
578+addConstraint alias constraint = UnsafeAlterTable $
579+ "ADD" <+> "CONSTRAINT" <+> renderAlias alias
580+ <+> renderTableConstraintExpression constraint
581+
582+-- | A `dropConstraint` drops a table constraint.
583+--
584+-- >>> :{
585+-- let
586+-- definition :: Definition
587+-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
588+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
589+-- definition = alterTable #tab (dropConstraint #positive)
590+-- in printSQL definition
591+-- :}
592+-- ALTER TABLE "tab" DROP CONSTRAINT "positive";
593+dropConstraint
594+ :: ( KnownSymbol constraint
595+ , Has tab schema ('Table table0)
596+ , table0 ~ (constraints :=> columns)
597+ , table1 ~ (Drop constraint constraints :=> columns) )
598+ => Alias constraint
599+ -- ^ constraint to drop
600+ -> AlterTable tab table1 schema
601+dropConstraint constraint = UnsafeAlterTable $
602+ "DROP" <+> "CONSTRAINT" <+> renderAlias constraint
603+
604+-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.
605+class AddColumn ty where
606+ -- | `addColumn` adds a new column, initially filled with whatever
607+ -- default value is given or with @NULL@.
608+ --
609+ -- >>> :{
610+ -- let
611+ -- definition :: Definition
612+ -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
613+ -- '["tab" ::: 'Table ('[] :=>
614+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
615+ -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]
616+ -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))
617+ -- in printSQL definition
618+ -- :}
619+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';
620+ --
621+ -- >>> :{
622+ -- let
623+ -- definition :: Definition
624+ -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
625+ -- '["tab" ::: 'Table ('[] :=>
626+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
627+ -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]
628+ -- definition = alterTable #tab (addColumn #col2 (text & nullable))
629+ -- in printSQL definition
630+ -- :}
631+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;
632+ addColumn
633+ :: ( KnownSymbol column
634+ , Has tab schema ('Table table0)
635+ , table0 ~ (constraints :=> columns)
636+ , table1 ~ (constraints :=> Create column ty columns) )
637+ => Alias column -- ^ column to add
638+ -> ColumnTypeExpression schema ty -- ^ type of the new column
639+ -> AlterTable tab table1 schema
640+ addColumn column ty = UnsafeAlterTable $
641+ "ADD COLUMN" <+> renderAlias column <+> renderColumnTypeExpression ty
642+instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)
643+instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)
644+
645+-- | A `dropColumn` removes a column. Whatever data was in the column
646+-- disappears. Table constraints involving the column are dropped, too.
647+-- However, if the column is referenced by a foreign key constraint of
648+-- another table, PostgreSQL will not silently drop that constraint.
649+--
650+-- >>> :{
651+-- let
652+-- definition :: Definition
653+-- '["tab" ::: 'Table ('[] :=>
654+-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
655+-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]
656+-- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]
657+-- definition = alterTable #tab (dropColumn #col2)
658+-- in printSQL definition
659+-- :}
660+-- ALTER TABLE "tab" DROP COLUMN "col2";
661+dropColumn
662+ :: ( KnownSymbol column
663+ , Has tab schema ('Table table0)
664+ , table0 ~ (constraints :=> columns)
665+ , table1 ~ (constraints :=> Drop column columns) )
666+ => Alias column -- ^ column to remove
667+ -> AlterTable tab table1 schema
668+dropColumn column = UnsafeAlterTable $
669+ "DROP COLUMN" <+> renderAlias column
670+
671+-- | A `renameColumn` renames a column.
672+--
673+-- >>> :{
674+-- let
675+-- definition :: Definition
676+-- '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]
677+-- '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]
678+-- definition = alterTable #tab (renameColumn #foo #bar)
679+-- in printSQL definition
680+-- :}
681+-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";
682+renameColumn
683+ :: ( KnownSymbol column0
684+ , KnownSymbol column1
685+ , Has tab schema ('Table table0)
686+ , table0 ~ (constraints :=> columns)
687+ , table1 ~ (constraints :=> Rename column0 column1 columns) )
688+ => Alias column0 -- ^ column to rename
689+ -> Alias column1 -- ^ what to rename the column
690+ -> AlterTable tab table1 schema
691+renameColumn column0 column1 = UnsafeAlterTable $
692+ "RENAME COLUMN" <+> renderAlias column0 <+> "TO" <+> renderAlias column1
693+
694+-- | An `alterColumn` alters a single column.
695+alterColumn
696+ :: ( KnownSymbol column
697+ , Has tab schema ('Table table0)
698+ , table0 ~ (constraints :=> columns)
699+ , Has column columns ty0
700+ , tables1 ~ (constraints :=> Alter column ty1 columns))
701+ => Alias column -- ^ column to alter
702+ -> AlterColumn schema ty0 ty1 -- ^ alteration to perform
703+ -> AlterTable tab table1 schema
704+alterColumn column alteration = UnsafeAlterTable $
705+ "ALTER COLUMN" <+> renderAlias column <+> renderAlterColumn alteration
706+
707+-- | An `AlterColumn` describes the alteration to perform on a single column.
708+newtype AlterColumn (schema :: SchemaType) (ty0 :: ColumnType) (ty1 :: ColumnType) =
709+ UnsafeAlterColumn {renderAlterColumn :: ByteString}
710+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
711+
712+-- | A `setDefault` sets a new default for a column. Note that this doesn't
713+-- affect any existing rows in the table, it just changes the default for
714+-- future insert and update commands.
715+--
716+-- >>> :{
717+-- let
718+-- definition :: Definition
719+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
720+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]
721+-- definition = alterTable #tab (alterColumn #col (setDefault 5))
722+-- in printSQL definition
723+-- :}
724+-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;
725+setDefault
726+ :: Expression schema '[] 'Ungrouped '[] ty -- ^ default value to set
727+ -> AlterColumn schema (constraint :=> ty) ('Def :=> ty)
728+setDefault expression = UnsafeAlterColumn $
729+ "SET DEFAULT" <+> renderExpression expression
730+
731+-- | A `dropDefault` removes any default value for a column.
732+--
733+-- >>> :{
734+-- let
735+-- definition :: Definition
736+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]
737+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
738+-- definition = alterTable #tab (alterColumn #col dropDefault)
739+-- in printSQL definition
740+-- :}
741+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;
742+dropDefault :: AlterColumn schema ('Def :=> ty) ('NoDef :=> ty)
743+dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"
744+
745+-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.
746+-- The constraint will be checked immediately, so the table data must satisfy
747+-- the constraint before it can be added.
748+--
749+-- >>> :{
750+-- let
751+-- definition :: Definition
752+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
753+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
754+-- definition = alterTable #tab (alterColumn #col setNotNull)
755+-- in printSQL definition
756+-- :}
757+-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;
758+setNotNull
759+ :: AlterColumn schema (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)
760+setNotNull = UnsafeAlterColumn $ "SET NOT NULL"
761+
762+-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.
763+--
764+-- >>> :{
765+-- let
766+-- definition :: Definition
767+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
768+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
769+-- definition = alterTable #tab (alterColumn #col dropNotNull)
770+-- in printSQL definition
771+-- :}
772+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;
773+dropNotNull
774+ :: AlterColumn schema (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)
775+dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"
776+
777+-- | An `alterType` converts a column to a different data type.
778+-- This will succeed only if each existing entry in the column can be
779+-- converted to the new type by an implicit cast.
780+--
781+-- >>> :{
782+-- let
783+-- definition :: Definition
784+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]
785+-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]
786+-- definition =
787+-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))
788+-- in printSQL definition
789+-- :}
790+-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;
791+alterType :: ColumnTypeExpression schema ty -> AlterColumn schema ty0 ty
792+alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty
793+
794+-- | Create a view.
795+--
796+-- >>> :{
797+-- let
798+-- definition :: Definition
799+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]
800+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
801+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]
802+-- definition =
803+-- createView #bc (select (#b :* #c) (from (table #abc)))
804+-- in printSQL definition
805+-- :}
806+-- CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";
807+createView
808+ :: KnownSymbol view
809+ => Alias view -- ^ the name of the view to add
810+ -> Query schema '[] relation
811+ -- ^ query
812+ -> Definition schema (Create view ('View relation) schema)
813+createView alias query = UnsafeDefinition $
814+ "CREATE" <+> "VIEW" <+> renderAlias alias <+> "AS"
815+ <+> renderQuery query <> ";"
816+
817+-- | Drop a view.
818+--
819+-- >>> :{
820+-- let
821+-- definition :: Definition
822+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
823+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]
824+-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]
825+-- definition = dropView #bc
826+-- in printSQL definition
827+-- :}
828+-- DROP VIEW "bc";
829+dropView
830+ :: Has view schema ('View v)
831+ => Alias view -- ^ view to remove
832+ -> Definition schema (Drop view schema)
833+dropView v = UnsafeDefinition $ "DROP VIEW" <+> renderAlias v <> ";"
834+
835+-- | Enumerated types are created using the `createTypeEnum` command, for example
836+--
837+-- >>> printSQL $ createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy")
838+-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');
839+createTypeEnum
840+ :: (KnownSymbol enum, SOP.All KnownSymbol labels)
841+ => Alias enum
842+ -- ^ name of the user defined enumerated type
843+ -> NP PGlabel labels
844+ -- ^ labels of the enumerated type
845+ -> Definition schema (Create enum ('Typedef ('PGenum labels)) schema)
846+createTypeEnum enum labels = UnsafeDefinition $
847+ "CREATE" <+> "TYPE" <+> renderAlias enum <+> "AS" <+> "ENUM" <+>
848+ parenthesized (commaSeparated (renderLabels labels)) <> ";"
849+
850+-- | Enumerated types can also be generated from a Haskell type, for example
851+--
852+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
853+-- >>> instance SOP.Generic Schwarma
854+-- >>> instance SOP.HasDatatypeInfo Schwarma
855+-- >>> printSQL $ createTypeEnumFrom @Schwarma #schwarma
856+-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');
857+createTypeEnumFrom
858+ :: forall hask enum schema.
859+ ( SOP.Generic hask
860+ , SOP.All KnownSymbol (LabelsFrom hask)
861+ , KnownSymbol enum
862+ )
863+ => Alias enum
864+ -- ^ name of the user defined enumerated type
865+ -> Definition schema (Create enum ('Typedef (EnumFrom hask)) schema)
866+createTypeEnumFrom enum = createTypeEnum enum
867+ (SOP.hpure label :: NP PGlabel (LabelsFrom hask))
868+
869+{- | `createTypeComposite` creates a composite type. The composite type is
870+specified by a list of attribute names and data types.
871+
872+>>> type PGcomplex = 'PGcomposite '["real" ::: 'PGfloat8, "imaginary" ::: 'PGfloat8]
873+
874+>>> :{
875+let
876+ setup :: Definition '[] '["complex" ::: 'Typedef PGcomplex]
877+ setup = createTypeComposite #complex
878+ (float8 `as` #real :* float8 `as` #imaginary)
879+in printSQL setup
880+:}
881+CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
882+-}
883+createTypeComposite
884+ :: (KnownSymbol ty, SOP.SListI fields)
885+ => Alias ty
886+ -- ^ name of the user defined composite type
887+ -> NP (Aliased (TypeExpression schema)) fields
888+ -- ^ list of attribute names and data types
889+ -> Definition schema (Create ty ('Typedef ('PGcomposite fields)) schema)
890+createTypeComposite ty fields = UnsafeDefinition $
891+ "CREATE" <+> "TYPE" <+> renderAlias ty <+> "AS" <+> parenthesized
892+ (renderCommaSeparated renderField fields) <> ";"
893+ where
894+ renderField :: Aliased (TypeExpression schema) x -> ByteString
895+ renderField (typ `As` field) =
896+ renderAlias field <+> renderTypeExpression typ
897+
898+-- | Composite types can also be generated from a Haskell type, for example
899+--
900+-- >>> data Complex = Complex {real :: Maybe Double, imaginary :: Maybe Double} deriving GHC.Generic
901+-- >>> instance SOP.Generic Complex
902+-- >>> instance SOP.HasDatatypeInfo Complex
903+-- >>> printSQL $ createTypeCompositeFrom @Complex #complex
904+-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
905+createTypeCompositeFrom
906+ :: forall hask ty schema.
907+ ( ZipAliased (FieldNamesFrom hask) (FieldTypesFrom hask)
908+ , SOP.All (PGTyped schema) (FieldTypesFrom hask)
909+ , KnownSymbol ty
910+ )
911+ => Alias ty
912+ -- ^ name of the user defined composite type
913+ -> Definition schema (Create ty ( 'Typedef (CompositeFrom hask)) schema)
914+createTypeCompositeFrom ty = createTypeComposite ty $ zipAs
915+ (SOP.hpure Alias :: NP Alias (FieldNamesFrom hask))
916+ (SOP.hcpure (SOP.Proxy :: SOP.Proxy (PGTyped schema)) pgtype
917+ :: NP (TypeExpression schema) (FieldTypesFrom hask))
918+
919+-- | Drop a type.
920+--
921+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
922+-- >>> instance SOP.Generic Schwarma
923+-- >>> instance SOP.HasDatatypeInfo Schwarma
924+-- >>> printSQL (dropType #schwarma :: Definition '["schwarma" ::: 'Typedef (EnumFrom Schwarma)] '[])
925+-- DROP TYPE "schwarma";
926+dropType
927+ :: Has tydef schema ('Typedef ty)
928+ => Alias tydef
929+ -- ^ name of the user defined type
930+ -> Definition schema (Drop tydef schema)
931+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderAlias tydef <> ";"
932+
933+-- | `ColumnTypeExpression`s are used in `createTable` commands.
934+newtype ColumnTypeExpression (schema :: SchemaType) (ty :: ColumnType)
935+ = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }
936+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
937+
938+-- | used in `createTable` commands as a column constraint to note that
939+-- @NULL@ may be present in a column
940+nullable
941+ :: TypeExpression schema ty
942+ -> ColumnTypeExpression schema ('NoDef :=> 'Null ty)
943+nullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NULL"
944+
945+-- | used in `createTable` commands as a column constraint to ensure
946+-- @NULL@ is not present in a column
947+notNullable
948+ :: TypeExpression schema ty
949+ -> ColumnTypeExpression schema (def :=> 'NotNull ty)
950+notNullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NOT NULL"
951+
952+-- | used in `createTable` commands as a column constraint to give a default
953+default_
954+ :: Expression schema '[] 'Ungrouped '[] ty
955+ -> ColumnTypeExpression schema ('NoDef :=> ty)
956+ -> ColumnTypeExpression schema ('Def :=> ty)
957+default_ x ty = UnsafeColumnTypeExpression $
958+ renderColumnTypeExpression ty <+> "DEFAULT" <+> renderExpression x
959+
960+-- | not a true type, but merely a notational convenience for creating
961+-- unique identifier columns with type `PGint2`
962+serial2, smallserial
963+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint2)
964+serial2 = UnsafeColumnTypeExpression "serial2"
965+smallserial = UnsafeColumnTypeExpression "smallserial"
966+-- | not a true type, but merely a notational convenience for creating
967+-- unique identifier columns with type `PGint4`
968+serial4, serial
969+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint4)
970+serial4 = UnsafeColumnTypeExpression "serial4"
971+serial = UnsafeColumnTypeExpression "serial"
972+-- | not a true type, but merely a notational convenience for creating
973+-- unique identifier columns with type `PGint8`
974+serial8, bigserial
975+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint8)
976+serial8 = UnsafeColumnTypeExpression "serial8"
977+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+1574−340
@@ -1,13 +1,14 @@
11{-|
2−Module: Squeal.PostgreSQL.Expression
2+Module: Squeal.PostgreSQL.Query
33Description: Squeal expressions
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
88Squeal expressions are the atoms used to build statements.
99-}
1010
11+{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
1112{-# LANGUAGE
1213 AllowAmbiguousTypes
1314 , ConstraintKinds
@@ -15,13 +16,11 @@ Squeal expressions are the atoms used to build statements.
1516 , FlexibleContexts
1617 , FlexibleInstances
1718 , FunctionalDependencies
18− , GADTs
1919 , GeneralizedNewtypeDeriving
2020 , LambdaCase
2121 , MagicHash
2222 , OverloadedStrings
2323 , ScopedTypeVariables
24− , StandaloneDeriving
2524 , TypeApplications
2625 , TypeFamilies
2726 , TypeInType
@@ -32,351 +31,516 @@ Squeal expressions are the atoms used to build statements.
3231
3332module Squeal.PostgreSQL.Expression
3433 ( -- * Expression
35− Expression (..)
36− , Expr
37− , type (-->)
38− , FunctionDB
39− , unsafeFunction
40− , function
41− , unsafeLeftOp
42− , leftOp
43− , unsafeRightOp
44− , rightOp
45− , Operator
46− , OperatorDB
34+ Expression (UnsafeExpression, renderExpression)
35+ , HasParameter (parameter)
36+ , param
37+ -- ** Null
38+ , null_
39+ , notNull
40+ , coalesce
41+ , fromNull
42+ , isNull
43+ , isNotNull
44+ , matchNull
45+ , nullIf
46+ -- ** Collections
47+ , array
48+ , row
49+ -- ** Functions
4750 , unsafeBinaryOp
48− , binaryOp
49− , FunctionVar
50− , unsafeFunctionVar
51− , type (--->)
52− , FunctionNDB
53− , unsafeFunctionN
54− , functionN
55− , PGSubset (..)
56− , PGIntersect (..)
51+ , unsafeUnaryOp
52+ , unsafeFunction
53+ , unsafeVariadicFunction
54+ , atan2_
55+ , cast
56+ , quot_
57+ , rem_
58+ , trunc
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+ , (.->)
95+ , (.->>)
96+ , (.#>)
97+ , (.#>>)
98+ -- *** jsonb only operators
99+ , (.@>)
100+ , (.<@)
101+ , (.?)
102+ , (.?|)
103+ , (.?&)
104+ , (.-.)
105+ , (#-.)
106+ -- *** Functions
107+ , jsonLit
108+ , jsonbLit
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+ , jsonExtractPath
124+ , jsonbExtractPath
125+ , jsonExtractPathAsText
126+ , jsonbExtractPathAsText
127+ , jsonObjectKeys
128+ , jsonbObjectKeys
129+ , jsonTypeof
130+ , jsonbTypeof
131+ , jsonStripNulls
132+ , jsonbStripNulls
133+ , jsonbSet
134+ , jsonbInsert
135+ , jsonbPretty
136+ -- ** Aggregation
137+ , unsafeAggregate, unsafeAggregateDistinct
138+ , sum_, sumDistinct
139+ , PGAvg (avg, avgDistinct)
140+ , bitAnd, bitOr, boolAnd, boolOr
141+ , bitAndDistinct, bitOrDistinct, boolAndDistinct, boolOrDistinct
142+ , countStar
143+ , count, countDistinct
144+ , every, everyDistinct
145+ , max_, maxDistinct, min_, minDistinct
146+ -- * Types
147+ , TypeExpression (UnsafeTypeExpression, renderTypeExpression)
148+ , PGTyped (pgtype)
149+ , bool
150+ , int2
151+ , smallint
152+ , int4
153+ , int
154+ , integer
155+ , int8
156+ , bigint
157+ , numeric
158+ , float4
159+ , real
160+ , float8
161+ , doublePrecision
162+ , text
163+ , char
164+ , character
165+ , varchar
166+ , characterVarying
167+ , bytea
168+ , timestamp
169+ , timestampWithTimeZone
170+ , date
171+ , time
172+ , timeWithTimeZone
173+ , interval
174+ , uuid
175+ , inet
176+ , json
177+ , jsonb
178+ , vararray
179+ , fixarray
57180 -- * Re-export
58181 , (&)
59− , K (..)
60− , unK
182+ , NP ((:*), Nil)
61183 ) where
62184
63185import Control.Category
64186import Control.DeepSeq
65187import Data.ByteString (ByteString)
188+import Data.ByteString.Lazy (toStrict)
66189import Data.Function ((&))
67190import Data.Semigroup hiding (All)
191+import qualified Data.Aeson as JSON
192+import Data.Ratio
68193import Data.String
69−import Generics.SOP hiding (All, from)
194+import Generics.SOP hiding (from)
70195import GHC.OverloadedLabels
71196import GHC.TypeLits
72−import Numeric
73197import Prelude hiding (id, (.))
74198
75199import qualified GHC.Generics as GHC
76200
77−import Squeal.PostgreSQL.Alias
78−import Squeal.PostgreSQL.List
79201import Squeal.PostgreSQL.Render
80202import Squeal.PostgreSQL.Schema
81203
82−-- $setup
83−-- >>> import Squeal.PostgreSQL
84−
85204{-----------------------------------------
86205column expressions
87206-----------------------------------------}
88207
89208{- | `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,
209+such as in the target list of the `Squeal.PostgreSQL.Query.select` command,
92210as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or
93211`Squeal.PostgreSQL.Manipulation.update`,
94−or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.
212+or in search `Condition`s in a number of commands.
95213
96214The expression syntax allows the calculation of
97215values from primitive expression using arithmetic, logical,
98216and 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`.
113217-}
114218newtype Expression
115− (outer :: FromType)
116− (commons :: FromType)
117− (grp :: Grouping)
118− (schemas :: SchemasType)
219+ (schema :: SchemaType)
220+ (relations :: RelationsType)
221+ (grouping :: Grouping)
119222 (params :: [NullityType])
120− (from :: FromType)
121223 (ty :: NullityType)
122224 = UnsafeExpression { renderExpression :: ByteString }
123225 deriving (GHC.Generic,Show,Eq,Ord,NFData)
124−instance RenderSQL (Expression outer commons grp schemas params from ty) where
226+
227+instance RenderSQL (Expression schema relations grouping params ty) where
125228 renderSQL = renderExpression
126229
127−-- | An `Expr` is a closed `Expression`.
128−-- It is a F@RankNType@ but don't be scared.
129−-- Think of it as an expression which sees no
130−-- namespaces, so you can't use parameters
131−-- or alias references. It can be used as
132−-- a simple piece of more complex `Expression`s.
133−type Expr x
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.
230+{- | A `HasParameter` constraint is used to indicate a value that is
231+supplied externally to a SQL statement.
232+`Squeal.PostgreSQL.PQ.manipulateParams`,
233+`Squeal.PostgreSQL.PQ.queryParams` and
234+`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values
235+separately from the SQL command string, in which case `param`s are used to
236+refer to the out-of-line data values.
198237-}
199−type FunctionVar x0 x1 y
200− = forall outer commons grp schemas params from
201− . [Expression outer commons grp schemas params from x0]
202− -- ^ inputs
203− -> Expression outer commons grp schemas params from x1
204− -- ^ must have at least 1 input
205− -> Expression outer commons grp schemas params from y
206− -- ^ output
207−
208−{- | >>> printSQL (unsafeFunctionVar "greatest" [true, null_] false)
209−greatest(TRUE, NULL, FALSE)
210−-}
211−unsafeFunctionVar :: ByteString -> FunctionVar x0 x1 y
212−unsafeFunctionVar fun xs x = UnsafeExpression $ fun <> parenthesized
213− (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)
214−
215−instance (HasUnique tab (Join outer from) row, Has col row ty)
216− => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where
217− fromLabel = UnsafeExpression $ renderSQL (Alias @col)
218−instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])
219− => IsLabel col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
220− fromLabel = fromLabel @col :* Nil
221−instance (HasUnique tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
222− => IsLabel col
223− (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
224− fromLabel = fromLabel @col `As` Alias
225−instance (HasUnique tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
226− => IsLabel col
227− (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
228− fromLabel = fromLabel @col :* Nil
229−
230−instance (Has tab (Join outer from) row, Has col row ty)
231− => IsQualified tab col (Expression outer commons 'Ungrouped schemas params from ty) where
232− tab ! col = UnsafeExpression $
233− renderSQL tab <> "." <> renderSQL col
234−instance (Has tab (Join outer from) row, Has col row ty, tys ~ '[ty])
235− => IsQualified tab col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
236− tab ! col = tab ! col :* Nil
237−instance (Has tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
238− => IsQualified tab col
239− (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
240− tab ! col = tab ! col `As` col
241−instance (Has tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
242− => IsQualified tab col
243− (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
244− tab ! col = tab ! col :* Nil
238+class KnownNat n => HasParameter
239+ (n :: Nat)
240+ (schema :: SchemaType)
241+ (params :: [NullityType])
242+ (ty :: NullityType)
243+ | n params -> ty where
244+ -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.
245+ --
246+ -- >>> let expr = parameter @1 int4 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)
247+ -- >>> printSQL expr
248+ -- ($1 :: int4)
249+ parameter
250+ :: TypeExpression schema (PGTypeOf ty)
251+ -> Expression schema relations grouping params ty
252+ parameter ty = UnsafeExpression $ parenthesized $
253+ "$" <> renderNat (Proxy @n) <+> "::"
254+ <+> renderTypeExpression ty
255+instance {-# OVERLAPPING #-} HasParameter 1 schema (ty1:tys) ty1
256+instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) schema params ty)
257+ => HasParameter n schema (ty' : params) ty
258+
259+-- | `param` takes a `Nat` using type application and for basic types,
260+-- infers a `TypeExpression`.
261+--
262+-- >>> let expr = param @1 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)
263+-- >>> printSQL expr
264+-- ($1 :: int4)
265+param
266+ :: forall n schema params relations grouping ty
267+ . (PGTyped schema (PGTypeOf ty), HasParameter n schema params ty)
268+ => Expression schema relations grouping params ty -- ^ param
269+param = parameter @n pgtype
270+
271+instance (HasUnique relation relations columns, Has column columns ty)
272+ => IsLabel column (Expression schema relations 'Ungrouped params ty) where
273+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)
274+instance (HasUnique relation relations columns, Has column columns ty)
275+ => IsLabel column
276+ (Aliased (Expression schema relations 'Ungrouped params) (column ::: ty)) where
277+ fromLabel = fromLabel @column `As` Alias @column
278+instance (HasUnique relation relations columns, Has column columns ty)
279+ => IsLabel column
280+ (NP (Aliased (Expression schema relations 'Ungrouped params)) '[column ::: ty]) where
281+ fromLabel = fromLabel @column :* Nil
282+
283+instance (Has relation relations columns, Has column columns ty)
284+ => IsQualified relation column (Expression schema relations 'Ungrouped params ty) where
285+ relation ! column = UnsafeExpression $
286+ renderAlias relation <> "." <> renderAlias column
287+instance (Has relation relations columns, Has column columns ty)
288+ => IsQualified relation column
289+ (Aliased (Expression schema relations 'Ungrouped params) (column ::: ty)) where
290+ relation ! column = relation ! column `As` column
291+instance (Has relation relations columns, Has column columns ty)
292+ => IsQualified relation column
293+ (NP (Aliased (Expression schema relations 'Ungrouped params)) '[column ::: ty]) where
294+ relation ! column = relation ! column :* Nil
245295
246296instance
247− ( HasUnique tab (Join outer from) row
248− , Has col row ty
249− , GroupedBy tab col bys
250− ) => IsLabel col
251− (Expression outer commons ('Grouped bys) schemas params from ty) where
252− fromLabel = UnsafeExpression $ renderSQL (Alias @col)
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
297+ ( HasUnique relation relations columns
298+ , Has column columns ty
299+ , GroupedBy relation column bys
300+ ) => IsLabel column
301+ (Expression schema relations ('Grouped bys) params ty) where
302+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)
261303instance
262− ( HasUnique tab (Join outer from) row
263− , Has col row ty
264− , GroupedBy tab col bys
265− , column ~ (col ::: ty)
266− ) => IsLabel col
267− (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
268− fromLabel = fromLabel @col `As` Alias
304+ ( HasUnique relation relations columns
305+ , Has column columns ty
306+ , GroupedBy relation column bys
307+ ) => IsLabel column
308+ ( Aliased (Expression schema relations ('Grouped bys) params)
309+ (column ::: ty) ) where
310+ fromLabel = fromLabel @column `As` Alias @column
269311instance
270− ( HasUnique tab (Join outer from) row
271− , Has col row ty
272− , GroupedBy tab col bys
273− , columns ~ '[col ::: ty]
274− ) => IsLabel col
275− (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
276− fromLabel = fromLabel @col :* Nil
312+ ( HasUnique relation relations columns
313+ , Has column columns ty
314+ , GroupedBy relation column bys
315+ ) => IsLabel column
316+ ( NP (Aliased (Expression schema relations ('Grouped bys) params))
317+ '[column ::: ty] ) where
318+ fromLabel = fromLabel @column :* Nil
277319
278320instance
279− ( Has tab (Join outer from) row
280− , Has col row ty
281− , GroupedBy tab col bys
282− ) => IsQualified tab col
283− (Expression outer commons ('Grouped bys) schemas params from ty) where
284− tab ! col = UnsafeExpression $
285− renderSQL tab <> "." <> renderSQL col
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
321+ ( Has relation relations columns
322+ , Has column columns ty
323+ , GroupedBy relation column bys
324+ ) => IsQualified relation column
325+ (Expression schema relations ('Grouped bys) params ty) where
326+ relation ! column = UnsafeExpression $
327+ renderAlias relation <> "." <> renderAlias column
294328instance
295− ( Has tab (Join outer from) row
296− , Has col row ty
297− , GroupedBy tab col bys
298− , column ~ (col ::: ty)
299− ) => IsQualified tab col
300− (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
301− tab ! col = tab ! col `As` col
329+ ( Has relation relations columns
330+ , Has column columns ty
331+ , GroupedBy relation column bys
332+ ) => IsQualified relation column
333+ (Aliased (Expression schema relations ('Grouped bys) params)
334+ (column ::: ty)) where
335+ relation ! column = relation ! column `As` column
302336instance
303− ( Has tab (Join outer from) row
304− , Has col row ty
305− , GroupedBy tab col bys
306− , columns ~ '[col ::: ty]
307− ) => IsQualified tab col
308− (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
309− tab ! col = tab ! col :* Nil
337+ ( Has relation relations columns
338+ , Has column columns ty
339+ , GroupedBy relation column bys
340+ ) => IsQualified relation column
341+ ( NP (Aliased (Expression schema relations ('Grouped bys) params))
342+ '[column ::: ty]) where
343+ relation ! column = relation ! column :* Nil
344+
345+-- | analagous to `Nothing`
346+--
347+-- >>> printSQL null_
348+-- NULL
349+null_ :: Expression schema rels grouping params ('Null ty)
350+null_ = UnsafeExpression "NULL"
351+
352+-- | analagous to `Just`
353+--
354+-- >>> printSQL $ notNull true
355+-- TRUE
356+notNull
357+ :: Expression schema rels grouping params ('NotNull ty)
358+ -> Expression schema rels grouping params ('Null ty)
359+notNull = UnsafeExpression . renderExpression
360+
361+-- | return the leftmost value which is not NULL
362+--
363+-- >>> printSQL $ coalesce [null_, notNull true] false
364+-- COALESCE(NULL, TRUE, FALSE)
365+coalesce
366+ :: [Expression schema relations grouping params ('Null ty)]
367+ -- ^ @NULL@s may be present
368+ -> Expression schema relations grouping params ('NotNull ty)
369+ -- ^ @NULL@ is absent
370+ -> Expression schema relations grouping params ('NotNull ty)
371+coalesce nullxs notNullx = UnsafeExpression $
372+ "COALESCE" <> parenthesized (commaSeparated
373+ ((renderExpression <$> nullxs) <> [renderExpression notNullx]))
374+
375+-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@
376+--
377+-- >>> printSQL $ fromNull true null_
378+-- COALESCE(NULL, TRUE)
379+fromNull
380+ :: Expression schema relations grouping params ('NotNull ty)
381+ -- ^ what to convert @NULL@ to
382+ -> Expression schema relations grouping params ('Null ty)
383+ -> Expression schema relations grouping params ('NotNull ty)
384+fromNull notNullx nullx = coalesce [nullx] notNullx
385+
386+-- | >>> printSQL $ null_ & isNull
387+-- NULL IS NULL
388+isNull
389+ :: Expression schema relations grouping params ('Null ty)
390+ -- ^ possibly @NULL@
391+ -> Condition schema relations grouping params
392+isNull x = UnsafeExpression $ renderExpression x <+> "IS NULL"
393+
394+-- | >>> printSQL $ null_ & isNotNull
395+-- NULL IS NOT NULL
396+isNotNull
397+ :: Expression schema relations grouping params ('Null ty)
398+ -- ^ possibly @NULL@
399+ -> Condition schema relations grouping params
400+isNotNull x = UnsafeExpression $ renderExpression x <+> "IS NOT NULL"
401+
402+-- | analagous to `maybe` using @IS NULL@
403+--
404+-- >>> printSQL $ matchNull true not_ null_
405+-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END
406+matchNull
407+ :: Expression schema relations grouping params (nullty)
408+ -- ^ what to convert @NULL@ to
409+ -> ( Expression schema relations grouping params ('NotNull ty)
410+ -> Expression schema relations grouping params (nullty) )
411+ -- ^ function to perform when @NULL@ is absent
412+ -> Expression schema relations grouping params ('Null ty)
413+ -> Expression schema relations grouping params (nullty)
414+matchNull y f x = ifThenElse (isNull x) y
415+ (f (UnsafeExpression (renderExpression x)))
416+
417+{-| right inverse to `fromNull`, if its arguments are equal then
418+`nullIf` gives @NULL@.
419+
420+>>> :set -XTypeApplications -XDataKinds
421+>>> let expr = nullIf false (param @1) :: Expression schema rels grp '[ 'NotNull 'PGbool] ('Null 'PGbool)
422+>>> printSQL expr
423+NULL IF (FALSE, ($1 :: bool))
424+-}
425+nullIf
426+ :: Expression schema relations grouping params ('NotNull ty)
427+ -- ^ @NULL@ is absent
428+ -> Expression schema relations grouping params ('NotNull ty)
429+ -- ^ @NULL@ is absent
430+ -> Expression schema relations grouping params ('Null ty)
431+nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized
432+ (renderExpression x <> ", " <> renderExpression y)
433+
434+-- | >>> printSQL $ array [null_, notNull false, notNull true]
435+-- ARRAY[NULL, FALSE, TRUE]
436+array
437+ :: [Expression schema relations grouping params ('Null ty)]
438+ -- ^ array elements
439+ -> Expression schema relations grouping params (nullity ('PGvararray ty))
440+array xs = UnsafeExpression $
441+ "ARRAY[" <> commaSeparated (renderExpression <$> xs) <> "]"
310442
311443instance (KnownSymbol label, label `In` labels) => IsPGlabel label
312− (Expression outer commons grp schemas params from (null ('PGenum labels))) where
313− label = UnsafeExpression $ renderSQL (PGlabel @label)
444+ (Expression schema relations grouping params (nullity ('PGenum labels))) where
445+ label = UnsafeExpression $ renderLabel (PGlabel @label)
446+
447+-- | A row constructor is an expression that builds a row value
448+-- (also called a composite value) using values for its member fields.
449+--
450+-- >>> type Complex = PGcomposite '["real" ::: 'PGfloat8, "imaginary" ::: 'PGfloat8]
451+-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression '[] '[] 'Ungrouped '[] ('NotNull Complex)
452+-- >>> printSQL i
453+-- ROW(0, 1)
454+row
455+ :: SListI (Nulls fields)
456+ => NP (Aliased (Expression schema relations grouping params)) (Nulls fields)
457+ -- ^ zero or more expressions for the row field values
458+ -> Expression schema relations grouping params (nullity ('PGcomposite fields))
459+row exprs = UnsafeExpression $ "ROW" <> parenthesized
460+ (renderCommaSeparated (\ (expr `As` _) -> renderExpression expr) exprs)
461+
462+instance Has field fields ty => IsLabel field
463+ ( Expression schema relation grouping params (nullity ('PGcomposite fields))
464+ -> Expression schema relation grouping params ('Null ty) ) where
465+ fromLabel expr = UnsafeExpression $
466+ parenthesized (renderExpression expr) <> "." <>
467+ fromString (symbolVal (Proxy @field))
468+
469+instance Semigroup
470+ (Expression schema relations grouping params (nullity ('PGvararray ty))) where
471+ (<>) = unsafeBinaryOp "||"
472+
473+instance Monoid
474+ (Expression schema relations grouping params (nullity ('PGvararray ty))) where
475+ mempty = array []
476+ mappend = (<>)
477+
478+-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression sch rels grp '[ 'NotNull 'PGtimestamptz] ('NotNull 'PGtimestamptz)
479+-- >>> printSQL expr
480+-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))
481+greatest
482+ :: Expression schema relations grouping params (nullty)
483+ -- ^ needs at least 1 argument
484+ -> [Expression schema relations grouping params (nullty)]
485+ -- ^ or more
486+ -> Expression schema relations grouping params (nullty)
487+greatest x xs = UnsafeExpression $ "GREATEST("
488+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"
489+
490+-- | >>> printSQL $ least currentTimestamp [null_]
491+-- LEAST(CURRENT_TIMESTAMP, NULL)
492+least
493+ :: Expression schema relations grouping params (nullty)
494+ -- ^ needs at least 1 argument
495+ -> [Expression schema relations grouping params (nullty)]
496+ -- ^ or more
497+ -> Expression schema relations grouping params (nullty)
498+least x xs = UnsafeExpression $ "LEAST("
499+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"
314500
315501-- | >>> printSQL $ unsafeBinaryOp "OR" true false
316502-- (TRUE OR FALSE)
317−unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2
503+unsafeBinaryOp
504+ :: ByteString
505+ -- ^ operator
506+ -> Expression schema relations grouping params (ty0)
507+ -> Expression schema relations grouping params (ty1)
508+ -> Expression schema relations grouping params (ty2)
318509unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $
319− renderSQL x <+> op <+> renderSQL 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
510+ renderExpression x <+> op <+> renderExpression y
327511
328−-- | >>> printSQL $ unsafeLeftOp "NOT" true
512+-- | >>> printSQL $ unsafeUnaryOp "NOT" true
329513-- (NOT TRUE)
330−unsafeLeftOp :: ByteString -> x --> y
331−unsafeLeftOp op x = UnsafeExpression $ parenthesized $ op <+> renderSQL x
332−
333−leftOp
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
344−
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
514+unsafeUnaryOp
515+ :: ByteString
516+ -- ^ operator
517+ -> Expression schema relations grouping params (ty0)
518+ -> Expression schema relations grouping params (ty1)
519+unsafeUnaryOp op x = UnsafeExpression $ parenthesized $
520+ op <+> renderExpression x
351521
352522-- | >>> printSQL $ unsafeFunction "f" true
353523-- f(TRUE)
354−unsafeFunction :: ByteString -> x --> y
524+unsafeFunction
525+ :: ByteString
526+ -- ^ function
527+ -> Expression schema relations grouping params (xty)
528+ -> Expression schema relations grouping params (yty)
355529unsafeFunction fun x = UnsafeExpression $
356− fun <> parenthesized (renderSQL x)
357−
358−function
359− :: (Has sch schemas schema, Has fun schema ('Function ('[x] :=> 'Returns y)))
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
367−unsafeFunctionN fun xs = UnsafeExpression $
368− fun <> parenthesized (renderCommaSeparated renderSQL xs)
369−
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
379− => Num (Expression outer commons grp schemas params from (null ty)) where
530+ fun <> parenthesized (renderExpression x)
531+
532+-- | Helper for defining variadic functions.
533+unsafeVariadicFunction
534+ :: SListI elems
535+ => ByteString
536+ -- ^ function
537+ -> NP (Expression schema relations grouping params) elems
538+ -> Expression schema relations grouping params ret
539+unsafeVariadicFunction fun x = UnsafeExpression $
540+ fun <> parenthesized (commaSeparated (hcollapse (hmap (K . renderExpression) x)))
541+
542+instance PGNum ty
543+ => Num (Expression schema relations grouping params (nullity ty)) where
380544 (+) = unsafeBinaryOp "+"
381545 (-) = unsafeBinaryOp "-"
382546 (*) = unsafeBinaryOp "*"
@@ -387,24 +551,19 @@ instance ty `In` PGNum
387551 . fromString
388552 . show
389553
390−instance (ty `In` PGNum, ty `In` PGFloating) => Fractional
391− (Expression outer commons grp schemas params from (null ty)) where
554+instance (PGNum ty, PGFloating ty) => Fractional
555+ (Expression schema relations grouping params (nullity ty)) where
392556 (/) = unsafeBinaryOp "/"
393− fromRational
394− = UnsafeExpression
395− . fromString
396− . ($ "")
397− . showFFloat Nothing
398− . fromRat @Double
557+ fromRational x = fromInteger (numerator x) / fromInteger (denominator x)
399558
400−instance (ty `In` PGNum, ty `In` PGFloating) => Floating
401− (Expression outer commons grp schemas params from (null ty)) where
559+instance (PGNum ty, PGFloating ty) => Floating
560+ (Expression schema relations grouping params (nullity ty)) where
402561 pi = UnsafeExpression "pi()"
403562 exp = unsafeFunction "exp"
404563 log = unsafeFunction "ln"
405564 sqrt = unsafeFunction "sqrt"
406565 b ** x = UnsafeExpression $
407− "power(" <> renderSQL b <> ", " <> renderSQL x <> ")"
566+ "power(" <> renderExpression b <> ", " <> renderExpression x <> ")"
408567 logBase b y = log y / log b
409568 sin = unsafeFunction "sin"
410569 cos = unsafeFunction "cos"
@@ -419,54 +578,1129 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating
419578 acosh x = log (x + sqrt (x*x - 1))
420579 atanh x = log ((1 + x) / (1 - x)) / 2
421580
422−-- | Contained by operators
423−class PGSubset ty where
424− (@>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
425− (@>) = unsafeBinaryOp "@>"
426− (<@) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
427− (<@) = unsafeBinaryOp "<@"
428−instance PGSubset 'PGjsonb
429−instance PGSubset 'PGtsquery
430−instance PGSubset ('PGvararray ty)
431−instance PGSubset ('PGrange ty)
432−
433−class PGIntersect ty where
434− (@&&) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)
435− (@&&) = unsafeBinaryOp "&&"
436−instance PGIntersect ('PGvararray ty)
437−instance PGIntersect ('PGrange ty)
581+-- | >>> :{
582+-- let
583+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
584+-- expression = atan2_ pi 2
585+-- in printSQL expression
586+-- :}
587+-- atan2(pi(), 2)
588+atan2_
589+ :: PGFloating float
590+ => Expression schema relations grouping params (nullity float)
591+ -- ^ numerator
592+ -> Expression schema relations grouping params (nullity float)
593+ -- ^ denominator
594+ -> Expression schema relations grouping params (nullity float)
595+atan2_ y x = UnsafeExpression $
596+ "atan2(" <> renderExpression y <> ", " <> renderExpression x <> ")"
597+
598+-- When a `cast` is applied to an `Expression` of a known type, it
599+-- represents a run-time type conversion. The cast will succeed only if a
600+-- suitable type conversion operation has been defined.
601+--
602+-- | >>> printSQL $ true & cast int4
603+-- (TRUE :: int4)
604+cast
605+ :: TypeExpression schema ty1
606+ -- ^ type to cast as
607+ -> Expression schema relations grouping params (nullity ty0)
608+ -- ^ value to convert
609+ -> Expression schema relations grouping params (nullity ty1)
610+cast ty x = UnsafeExpression $ parenthesized $
611+ renderExpression x <+> "::" <+> renderTypeExpression ty
612+
613+-- | integer division, truncates the result
614+--
615+-- >>> :{
616+-- let
617+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
618+-- expression = 5 `quot_` 2
619+-- in printSQL expression
620+-- :}
621+-- (5 / 2)
622+quot_
623+ :: PGIntegral int
624+ => Expression schema relations grouping params (nullity int)
625+ -- ^ numerator
626+ -> Expression schema relations grouping params (nullity int)
627+ -- ^ denominator
628+ -> Expression schema relations grouping params (nullity int)
629+quot_ = unsafeBinaryOp "/"
630+
631+-- | remainder upon integer division
632+--
633+-- >>> :{
634+-- let
635+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
636+-- expression = 5 `rem_` 2
637+-- in printSQL expression
638+-- :}
639+-- (5 % 2)
640+rem_
641+ :: PGIntegral int
642+ => Expression schema relations grouping params (nullity int)
643+ -- ^ numerator
644+ -> Expression schema relations grouping params (nullity int)
645+ -- ^ denominator
646+ -> Expression schema relations grouping params (nullity int)
647+rem_ = unsafeBinaryOp "%"
648+
649+-- | >>> :{
650+-- let
651+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
652+-- expression = trunc pi
653+-- in printSQL expression
654+-- :}
655+-- trunc(pi())
656+trunc
657+ :: PGFloating frac
658+ => Expression schema relations grouping params (nullity frac)
659+ -- ^ fractional number
660+ -> Expression schema relations grouping params (nullity frac)
661+trunc = unsafeFunction "trunc"
662+
663+-- | >>> :{
664+-- let
665+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
666+-- expression = round_ pi
667+-- in printSQL expression
668+-- :}
669+-- round(pi())
670+round_
671+ :: PGFloating frac
672+ => Expression schema relations grouping params (nullity frac)
673+ -- ^ fractional number
674+ -> Expression schema relations grouping params (nullity frac)
675+round_ = unsafeFunction "round"
676+
677+-- | >>> :{
678+-- let
679+-- expression :: Expression schema relations grouping params (nullity 'PGfloat4)
680+-- expression = ceiling_ pi
681+-- in printSQL expression
682+-- :}
683+-- ceiling(pi())
684+ceiling_
685+ :: PGFloating frac
686+ => Expression schema relations grouping params (nullity frac)
687+ -- ^ fractional number
688+ -> Expression schema relations grouping params (nullity frac)
689+ceiling_ = unsafeFunction "ceiling"
690+
691+-- | A `Condition` is a boolean valued `Expression`. While SQL allows
692+-- conditions to have @NULL@, Squeal instead chooses to disallow @NULL@,
693+-- forcing one to handle the case of @NULL@ explicitly to produce
694+-- a `Condition`.
695+type Condition schema relations grouping params =
696+ Expression schema relations grouping params ('NotNull 'PGbool)
697+
698+-- | >>> printSQL true
699+-- TRUE
700+true :: Condition schema relations grouping params
701+true = UnsafeExpression "TRUE"
702+
703+-- | >>> printSQL false
704+-- FALSE
705+false :: Condition schema relations grouping params
706+false = UnsafeExpression "FALSE"
707+
708+-- | >>> printSQL $ not_ true
709+-- (NOT TRUE)
710+not_
711+ :: Condition schema relations grouping params
712+ -> Condition schema relations grouping params
713+not_ = unsafeUnaryOp "NOT"
714+
715+-- | >>> printSQL $ true .&& false
716+-- (TRUE AND FALSE)
717+(.&&)
718+ :: Condition schema relations grouping params
719+ -> Condition schema relations grouping params
720+ -> Condition schema relations grouping params
721+(.&&) = unsafeBinaryOp "AND"
722+
723+-- | >>> printSQL $ true .|| false
724+-- (TRUE OR FALSE)
725+(.||)
726+ :: Condition schema relations grouping params
727+ -> Condition schema relations grouping params
728+ -> Condition schema relations grouping params
729+(.||) = unsafeBinaryOp "OR"
730+
731+-- | >>> :{
732+-- let
733+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
734+-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3
735+-- in printSQL expression
736+-- :}
737+-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END
738+caseWhenThenElse
739+ :: [ ( Condition schema relations grouping params
740+ , Expression schema relations grouping params (ty)
741+ ) ]
742+ -- ^ whens and thens
743+ -> Expression schema relations grouping params (ty)
744+ -- ^ else
745+ -> Expression schema relations grouping params (ty)
746+caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat
747+ [ "CASE"
748+ , mconcat
749+ [ mconcat
750+ [ " WHEN ", renderExpression when_
751+ , " THEN ", renderExpression then_
752+ ]
753+ | (when_,then_) <- whenThens
754+ ]
755+ , " ELSE ", renderExpression else_
756+ , " END"
757+ ]
758+
759+-- | >>> :{
760+-- let
761+-- expression :: Expression schema relations grouping params (nullity 'PGint2)
762+-- expression = ifThenElse true 1 0
763+-- in printSQL expression
764+-- :}
765+-- CASE WHEN TRUE THEN 1 ELSE 0 END
766+ifThenElse
767+ :: Condition schema relations grouping params
768+ -> Expression schema relations grouping params (ty) -- ^ then
769+ -> Expression schema relations grouping params (ty) -- ^ else
770+ -> Expression schema relations grouping params (ty)
771+ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_
772+
773+-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`
774+-- will produce @NULL@s if one of their arguments is @NULL@.
775+--
776+-- >>> printSQL $ notNull true .== null_
777+-- (TRUE = NULL)
778+(.==)
779+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
780+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
781+ -> Expression schema relations grouping params (nullity 'PGbool)
782+(.==) = unsafeBinaryOp "="
783+infix 4 .==
784+
785+-- | >>> printSQL $ notNull true ./= null_
786+-- (TRUE <> NULL)
787+(./=)
788+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
789+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
790+ -> Expression schema relations grouping params (nullity 'PGbool)
791+(./=) = unsafeBinaryOp "<>"
792+infix 4 ./=
793+
794+-- | >>> printSQL $ notNull true .>= null_
795+-- (TRUE >= NULL)
796+(.>=)
797+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
798+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
799+ -> Expression schema relations grouping params (nullity 'PGbool)
800+(.>=) = unsafeBinaryOp ">="
801+infix 4 .>=
802+
803+-- | >>> printSQL $ notNull true .< null_
804+-- (TRUE < NULL)
805+(.<)
806+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
807+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
808+ -> Expression schema relations grouping params (nullity 'PGbool)
809+(.<) = unsafeBinaryOp "<"
810+infix 4 .<
811+
812+-- | >>> printSQL $ notNull true .<= null_
813+-- (TRUE <= NULL)
814+(.<=)
815+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
816+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
817+ -> Expression schema relations grouping params (nullity 'PGbool)
818+(.<=) = unsafeBinaryOp "<="
819+infix 4 .<=
820+
821+-- | >>> printSQL $ notNull true .> null_
822+-- (TRUE > NULL)
823+(.>)
824+ :: Expression schema relations grouping params (nullity ty) -- ^ lhs
825+ -> Expression schema relations grouping params (nullity ty) -- ^ rhs
826+ -> Expression schema relations grouping params (nullity 'PGbool)
827+(.>) = unsafeBinaryOp ">"
828+infix 4 .>
829+
830+-- | >>> printSQL currentDate
831+-- CURRENT_DATE
832+currentDate
833+ :: Expression schema relations grouping params (nullity 'PGdate)
834+currentDate = UnsafeExpression "CURRENT_DATE"
835+
836+-- | >>> printSQL currentTime
837+-- CURRENT_TIME
838+currentTime
839+ :: Expression schema relations grouping params (nullity 'PGtimetz)
840+currentTime = UnsafeExpression "CURRENT_TIME"
841+
842+-- | >>> printSQL currentTimestamp
843+-- CURRENT_TIMESTAMP
844+currentTimestamp
845+ :: Expression schema relations grouping params (nullity 'PGtimestamptz)
846+currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"
847+
848+-- | >>> printSQL localTime
849+-- LOCALTIME
850+localTime
851+ :: Expression schema relations grouping params (nullity 'PGtime)
852+localTime = UnsafeExpression "LOCALTIME"
853+
854+-- | >>> printSQL localTimestamp
855+-- LOCALTIMESTAMP
856+localTimestamp
857+ :: Expression schema relations grouping params (nullity 'PGtimestamp)
858+localTimestamp = UnsafeExpression "LOCALTIMESTAMP"
859+
860+{-----------------------------------------
861+text
862+-----------------------------------------}
438863
439864instance IsString
440− (Expression outer commons grp schemas params from (null 'PGtext)) where
865+ (Expression schema relations grouping params (nullity 'PGtext)) where
441866 fromString str = UnsafeExpression $
442867 "E\'" <> fromString (escape =<< str) <> "\'"
443−instance IsString
444− (Expression outer commons grp schemas params from (null 'PGtsvector)) where
445− fromString str = UnsafeExpression . parenthesized . (<> " :: tsvector") $
446− "E\'" <> fromString (escape =<< str) <> "\'"
447−instance IsString
448− (Expression outer commons grp schemas params from (null 'PGtsquery)) where
449− fromString str = UnsafeExpression . parenthesized . (<> " :: tsquery") $
450− "E\'" <> fromString (escape =<< str) <> "\'"
868+ where
869+ escape = \case
870+ '\NUL' -> "\\0"
871+ '\'' -> "''"
872+ '"' -> "\\\""
873+ '\b' -> "\\b"
874+ '\n' -> "\\n"
875+ '\r' -> "\\r"
876+ '\t' -> "\\t"
877+ '\\' -> "\\\\"
878+ c -> [c]
451879
452880instance Semigroup
453− (Expression outer commons grp schemas params from (null ('PGvararray ty))) 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
881+ (Expression schema relations grouping params (nullity 'PGtext)) where
463882 (<>) = unsafeBinaryOp "||"
464883
465884instance Monoid
466− (Expression outer commons grp schemas params from (null 'PGtext)) where
467− mempty = fromString ""
468− mappend = (<>)
469−instance Monoid
470− (Expression outer commons grp schemas params from (null 'PGtsvector)) where
885+ (Expression schema relations grouping params (nullity 'PGtext)) where
471886 mempty = fromString ""
472887 mappend = (<>)
888+
889+-- | >>> printSQL $ lower "ARRRGGG"
890+-- lower(E'ARRRGGG')
891+lower
892+ :: Expression schema relations grouping params (nullity 'PGtext)
893+ -- ^ string to lower case
894+ -> Expression schema relations grouping params (nullity 'PGtext)
895+lower = unsafeFunction "lower"
896+
897+-- | >>> printSQL $ upper "eeee"
898+-- upper(E'eeee')
899+upper
900+ :: Expression schema relations grouping params (nullity 'PGtext)
901+ -- ^ string to upper case
902+ -> Expression schema relations grouping params (nullity 'PGtext)
903+upper = unsafeFunction "upper"
904+
905+-- | >>> printSQL $ charLength "four"
906+-- char_length(E'four')
907+charLength
908+ :: Expression schema relations grouping params (nullity 'PGtext)
909+ -- ^ string to measure
910+ -> Expression schema relations grouping params (nullity 'PGint4)
911+charLength = unsafeFunction "char_length"
912+
913+-- | The `like` expression returns true if the @string@ matches
914+-- the supplied @pattern@. If @pattern@ does not contain percent signs
915+-- or underscores, then the pattern only represents the string itself;
916+-- in that case `like` acts like the equals operator. An underscore (_)
917+-- in pattern stands for (matches) any single character; a percent sign (%)
918+-- matches any sequence of zero or more characters.
919+--
920+-- >>> printSQL $ "abc" `like` "a%"
921+-- (E'abc' LIKE E'a%')
922+like
923+ :: Expression schema relations grouping params (nullity 'PGtext)
924+ -- ^ string
925+ -> Expression schema relations grouping params (nullity 'PGtext)
926+ -- ^ pattern
927+ -> Expression schema relations grouping params (nullity 'PGbool)
928+like = unsafeBinaryOp "LIKE"
929+
930+{-----------------------------------------
931+ -- json and jsonb support
932+
933+See https://www.postgresql.org/docs/10/static/functions-json.html -- most
934+comments lifted directly from this page.
935+
936+Table 9.44: json and jsonb operators
937+-----------------------------------------}
938+
939+-- | Get JSON value (object field or array element) at a key.
940+(.->)
941+ :: (PGjson_ json, PGjsonKey key)
942+ => Expression schema relations grouping params (nullity json)
943+ -> Expression schema relations grouping params (nullity key)
944+ -> Expression schema relations grouping params ('Null json)
945+(.->) = unsafeBinaryOp "->"
946+
947+-- | Get JSON value (object field or array element) at a key, as text.
948+(.->>)
949+ :: (PGjson_ json, PGjsonKey key)
950+ => Expression schema relations grouping params (nullity json)
951+ -> Expression schema relations grouping params (nullity key)
952+ -> Expression schema relations grouping params ('Null 'PGtext)
953+(.->>) = unsafeBinaryOp "->>"
954+
955+-- | Get JSON value at a specified path.
956+(.#>)
957+ :: (PGjson_ json, PGtextArray "(.#>)" path)
958+ => Expression schema relations grouping params (nullity json)
959+ -> Expression schema relations grouping params (nullity path)
960+ -> Expression schema relations grouping params ('Null json)
961+(.#>) = unsafeBinaryOp "#>"
962+
963+-- | Get JSON value at a specified path as text.
964+(.#>>)
965+ :: (PGjson_ json, PGtextArray "(.#>>)" path)
966+ => Expression schema relations grouping params (nullity json)
967+ -> Expression schema relations grouping params (nullity path)
968+ -> Expression schema relations grouping params ('Null 'PGtext)
969+(.#>>) = unsafeBinaryOp "#>>"
970+
971+-- Additional jsonb operators
972+
973+-- | Does the left JSON value contain the right JSON path/value entries at the
974+-- top level?
975+(.@>)
976+ :: Expression schema relations grouping params (nullity 'PGjsonb)
977+ -> Expression schema relations grouping params (nullity 'PGjsonb)
978+ -> Condition schema relations grouping params
979+(.@>) = unsafeBinaryOp "@>"
980+
981+-- | Are the left JSON path/value entries contained at the top level within the
982+-- right JSON value?
983+(.<@)
984+ :: Expression schema relations grouping params (nullity 'PGjsonb)
985+ -> Expression schema relations grouping params (nullity 'PGjsonb)
986+ -> Condition schema relations grouping params
987+(.<@) = unsafeBinaryOp "<@"
988+
989+-- | Does the string exist as a top-level key within the JSON value?
990+(.?)
991+ :: Expression schema relations grouping params (nullity 'PGjsonb)
992+ -> Expression schema relations grouping params (nullity 'PGtext)
993+ -> Condition schema relations grouping params
994+(.?) = unsafeBinaryOp "?"
995+
996+-- | Do any of these array strings exist as top-level keys?
997+(.?|)
998+ :: Expression schema relations grouping params (nullity 'PGjsonb)
999+ -> Expression schema relations grouping params (nullity ('PGvararray 'PGtext))
1000+ -> Condition schema relations grouping params
1001+(.?|) = unsafeBinaryOp "?|"
1002+
1003+-- | Do all of these array strings exist as top-level keys?
1004+(.?&)
1005+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1006+ -> Expression schema relations grouping params (nullity ('PGvararray 'PGtext))
1007+ -> Condition schema relations grouping params
1008+(.?&) = unsafeBinaryOp "?&"
1009+
1010+-- | Concatenate two jsonb values into a new jsonb value.
1011+instance
1012+ Semigroup (Expression schema relations grouping param (nullity 'PGjsonb)) where
1013+ (<>) = unsafeBinaryOp "||"
1014+
1015+-- | Delete a key or keys from a JSON object, or remove an array element.
1016+--
1017+-- If the right operand is..
1018+--
1019+-- @ text @: Delete key/value pair or string element from left operand. Key/value pairs
1020+-- are matched based on their key value.
1021+--
1022+-- @ text[] @: Delete multiple key/value pairs or string elements
1023+-- from left operand. Key/value pairs are matched based on their key value.
1024+--
1025+-- @ integer @: Delete the array element with specified index (Negative integers
1026+-- count from the end). Throws an error if top level container is not an array.
1027+(.-.)
1028+ :: (key `In` '[ 'PGtext, 'PGvararray 'PGtext, 'PGint4, 'PGint2 ]) -- hlint error without parens here
1029+ => Expression schema relations grouping params (nullity 'PGjsonb)
1030+ -> Expression schema relations grouping params (nullity key)
1031+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1032+(.-.) = unsafeBinaryOp "-"
1033+
1034+-- | Delete the field or element with specified path (for JSON arrays, negative
1035+-- integers count from the end)
1036+(#-.)
1037+ :: PGtextArray "(#-.)" arrayty
1038+ => Expression schema relations grouping params (nullity 'PGjsonb)
1039+ -> Expression schema relations grouping params (nullity arrayty)
1040+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1041+(#-.) = unsafeBinaryOp "#-"
1042+
1043+{-----------------------------------------
1044+Table 9.45: JSON creation functions
1045+-----------------------------------------}
1046+
1047+-- | Literal binary JSON
1048+jsonbLit :: JSON.Value -> Expression schema relations grouping params (nullity 'PGjsonb)
1049+jsonbLit = cast jsonb . UnsafeExpression . singleQuotedUtf8 . toStrict . JSON.encode
1050+
1051+-- | Literal JSON
1052+jsonLit :: JSON.Value -> Expression schema relations grouping params (nullity 'PGjson)
1053+jsonLit = cast json . UnsafeExpression . singleQuotedUtf8 . toStrict . JSON.encode
1054+
1055+-- | Returns the value as json. Arrays and composites are converted
1056+-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1057+-- type to json, the cast function will be used to perform the conversion;
1058+-- otherwise, a scalar value is produced. For any scalar type other than a
1059+-- number, a Boolean, or a null value, the text representation will be used, in
1060+-- such a fashion that it is a valid json value.
1061+toJson
1062+ :: Expression schema relations grouping params (nullity ty)
1063+ -> Expression schema relations grouping params (nullity 'PGjson)
1064+toJson = unsafeFunction "to_json"
1065+
1066+-- | Returns the value as jsonb. Arrays and composites are converted
1067+-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1068+-- type to json, the cast function will be used to perform the conversion;
1069+-- otherwise, a scalar value is produced. For any scalar type other than a
1070+-- number, a Boolean, or a null value, the text representation will be used, in
1071+-- such a fashion that it is a valid jsonb value.
1072+toJsonb
1073+ :: Expression schema relations grouping params (nullity ty)
1074+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1075+toJsonb = unsafeFunction "to_jsonb"
1076+
1077+-- | Returns the array as a JSON array. A PostgreSQL multidimensional array
1078+-- becomes a JSON array of arrays.
1079+arrayToJson
1080+ :: PGarray "arrayToJson" arr
1081+ => Expression schema relations grouping params (nullity arr)
1082+ -> Expression schema relations grouping params (nullity 'PGjson)
1083+arrayToJson = unsafeFunction "array_to_json"
1084+
1085+-- | Returns the row as a JSON object.
1086+rowToJson
1087+ :: Expression schema relations grouping params (nullity ('PGcomposite ty))
1088+ -> Expression schema relations grouping params (nullity 'PGjson)
1089+rowToJson = unsafeFunction "row_to_json"
1090+
1091+-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic
1092+-- argument list.
1093+jsonBuildArray
1094+ :: SListI elems
1095+ => NP (Expression schema relations grouping params) elems
1096+ -> Expression schema relations grouping params (nullity 'PGjson)
1097+jsonBuildArray = unsafeVariadicFunction "json_build_array"
1098+
1099+-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a
1100+-- variadic argument list.
1101+jsonbBuildArray
1102+ :: SListI elems
1103+ => NP (Expression schema relations grouping params) elems
1104+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1105+jsonbBuildArray = unsafeVariadicFunction "jsonb_build_array"
1106+
1107+unsafeRowFunction
1108+ :: All Top elems
1109+ => NP (Aliased (Expression schema relations grouping params)) elems
1110+ -> [ByteString]
1111+unsafeRowFunction =
1112+ (`appEndo` []) . hcfoldMap (Proxy :: Proxy Top)
1113+ (\(col `As` name) -> Endo $ \xs ->
1114+ renderAliasString name : renderExpression col : xs)
1115+
1116+-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic
1117+-- argument list. The elements of the argument list must alternate between text
1118+-- and values.
1119+jsonBuildObject
1120+ :: All Top elems
1121+ => NP (Aliased (Expression schema relations grouping params)) elems
1122+ -> Expression schema relations grouping params (nullity 'PGjson)
1123+jsonBuildObject
1124+ = unsafeFunction "json_build_object"
1125+ . UnsafeExpression
1126+ . commaSeparated
1127+ . unsafeRowFunction
1128+
1129+-- | Builds a possibly-heterogeneously-typed (binary) JSON object out of a
1130+-- variadic argument list. The elements of the argument list must alternate
1131+-- between text and values.
1132+jsonbBuildObject
1133+ :: All Top elems
1134+ => NP (Aliased (Expression schema relations grouping params)) elems
1135+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1136+jsonbBuildObject
1137+ = unsafeFunction "jsonb_build_object"
1138+ . UnsafeExpression
1139+ . commaSeparated
1140+ . unsafeRowFunction
1141+
1142+-- | Builds a JSON object out of a text array. The array must have either
1143+-- exactly one dimension with an even number of members, in which case they are
1144+-- taken as alternating key/value pairs, or two dimensions such that each inner
1145+-- array has exactly two elements, which are taken as a key/value pair.
1146+jsonObject
1147+ :: PGarrayOf "jsonObject" arr 'PGtext
1148+ => Expression schema relations grouping params (nullity arr)
1149+ -> Expression schema relations grouping params (nullity 'PGjson)
1150+jsonObject = unsafeFunction "json_object"
1151+
1152+-- | Builds a binary JSON object out of a text array. The array must have either
1153+-- exactly one dimension with an even number of members, in which case they are
1154+-- taken as alternating key/value pairs, or two dimensions such that each inner
1155+-- array has exactly two elements, which are taken as a key/value pair.
1156+jsonbObject
1157+ :: PGarrayOf "jsonbObject" arr 'PGtext
1158+ => Expression schema relations grouping params (nullity arr)
1159+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1160+jsonbObject = unsafeFunction "jsonb_object"
1161+
1162+-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1163+-- keys and one for values, that are zipped pairwise to create a JSON object.
1164+jsonZipObject
1165+ :: ( PGarrayOf "jsonZipObject" keysArray 'PGtext
1166+ , PGarrayOf "jsonZipObject" valuesArray 'PGtext)
1167+ => Expression schema relations grouping params (nullity keysArray)
1168+ -> Expression schema relations grouping params (nullity valuesArray)
1169+ -> Expression schema relations grouping params (nullity 'PGjson)
1170+jsonZipObject ks vs =
1171+ unsafeVariadicFunction "json_object" (ks :* vs :* Nil)
1172+
1173+-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1174+-- keys and one for values, that are zipped pairwise to create a binary JSON
1175+-- object.
1176+jsonbZipObject
1177+ :: ( PGarrayOf "jsonbZipObject" keysArray 'PGtext
1178+ , PGarrayOf "jsonbZipObject" valuesArray 'PGtext)
1179+ => Expression schema relations grouping params (nullity keysArray)
1180+ -> Expression schema relations grouping params (nullity valuesArray)
1181+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1182+jsonbZipObject ks vs =
1183+ unsafeVariadicFunction "jsonb_object" (ks :* vs :* Nil)
1184+
1185+{-----------------------------------------
1186+Table 9.46: JSON processing functions
1187+-----------------------------------------}
1188+
1189+-- | Returns the number of elements in the outermost JSON array.
1190+jsonArrayLength
1191+ :: Expression schema relations grouping params (nullity 'PGjson)
1192+ -> Expression schema relations grouping params (nullity 'PGint4)
1193+jsonArrayLength = unsafeFunction "json_array_length"
1194+
1195+-- | Returns the number of elements in the outermost binary JSON array.
1196+jsonbArrayLength
1197+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1198+ -> Expression schema relations grouping params (nullity 'PGint4)
1199+jsonbArrayLength = unsafeFunction "jsonb_array_length"
1200+
1201+-- | Returns JSON value pointed to by the given path (equivalent to #>
1202+-- operator).
1203+jsonExtractPath
1204+ :: SListI elems
1205+ => Expression schema relations grouping params (nullity 'PGjson)
1206+ -> NP (Expression schema relations grouping params) elems
1207+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1208+jsonExtractPath x xs =
1209+ unsafeVariadicFunction "json_extract_path" (x :* xs)
1210+
1211+-- | Returns JSON value pointed to by the given path (equivalent to #>
1212+-- operator).
1213+jsonbExtractPath
1214+ :: SListI elems
1215+ => Expression schema relations grouping params (nullity 'PGjsonb)
1216+ -> NP (Expression schema relations grouping params) elems
1217+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1218+jsonbExtractPath x xs =
1219+ unsafeVariadicFunction "jsonb_extract_path" (x :* xs)
1220+
1221+-- | Returns JSON value pointed to by the given path (equivalent to #>
1222+-- operator), as text.
1223+jsonExtractPathAsText
1224+ :: SListI elems
1225+ => Expression schema relations grouping params (nullity 'PGjson)
1226+ -> NP (Expression schema relations grouping params) elems
1227+ -> Expression schema relations grouping params (nullity 'PGjson)
1228+jsonExtractPathAsText x xs =
1229+ unsafeVariadicFunction "json_extract_path_text" (x :* xs)
1230+
1231+-- | Returns JSON value pointed to by the given path (equivalent to #>
1232+-- operator), as text.
1233+jsonbExtractPathAsText
1234+ :: SListI elems
1235+ => Expression schema relations grouping params (nullity 'PGjsonb)
1236+ -> NP (Expression schema relations grouping params) elems
1237+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1238+jsonbExtractPathAsText x xs =
1239+ unsafeVariadicFunction "jsonb_extract_path_text" (x :* xs)
1240+
1241+-- | Returns set of keys in the outermost JSON object.
1242+jsonObjectKeys
1243+ :: Expression schema relations grouping params (nullity 'PGjson)
1244+ -> Expression schema relations grouping params (nullity 'PGtext)
1245+jsonObjectKeys = unsafeFunction "json_object_keys"
1246+
1247+-- | Returns set of keys in the outermost JSON object.
1248+jsonbObjectKeys
1249+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1250+ -> Expression schema relations grouping params (nullity 'PGtext)
1251+jsonbObjectKeys = unsafeFunction "jsonb_object_keys"
1252+
1253+-- | Returns the type of the outermost JSON value as a text string. Possible
1254+-- types are object, array, string, number, boolean, and null.
1255+jsonTypeof
1256+ :: Expression schema relations grouping params (nullity 'PGjson)
1257+ -> Expression schema relations grouping params (nullity 'PGtext)
1258+jsonTypeof = unsafeFunction "json_typeof"
1259+
1260+-- | Returns the type of the outermost binary JSON value as a text string.
1261+-- Possible types are object, array, string, number, boolean, and null.
1262+jsonbTypeof
1263+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1264+ -> Expression schema relations grouping params (nullity 'PGtext)
1265+jsonbTypeof = unsafeFunction "jsonb_typeof"
1266+
1267+-- | Returns its argument with all object fields that have null values omitted.
1268+-- Other null values are untouched.
1269+jsonStripNulls
1270+ :: Expression schema relations grouping params (nullity 'PGjson)
1271+ -> Expression schema relations grouping params (nullity 'PGjson)
1272+jsonStripNulls = unsafeFunction "json_strip_nulls"
1273+
1274+-- | Returns its argument with all object fields that have null values omitted.
1275+-- Other null values are untouched.
1276+jsonbStripNulls
1277+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1278+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1279+jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"
1280+
1281+-- | @ jsonbSet target path new_value create_missing @
1282+--
1283+-- Returns target with the section designated by path replaced by new_value,
1284+-- or with new_value added if create_missing is true ( default is true) and the
1285+-- item designated by path does not exist. As with the path orientated
1286+-- operators, negative integers that appear in path count from the end of JSON
1287+-- arrays.
1288+jsonbSet
1289+ :: PGtextArray "jsonbSet" arr
1290+ => Expression schema relations grouping params (nullity 'PGjsonb)
1291+ -> Expression schema relations grouping params (nullity arr)
1292+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1293+ -> Maybe (Expression schema relations grouping params (nullity 'PGbool))
1294+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1295+jsonbSet tgt path val createMissing = case createMissing of
1296+ Just m -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* m :* Nil)
1297+ Nothing -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* Nil)
1298+
1299+-- | @ jsonbInsert target path new_value insert_after @
1300+--
1301+-- Returns target with new_value inserted. If target section designated by
1302+-- path is in a JSONB array, new_value will be inserted before target or after
1303+-- if insert_after is true (default is false). If target section designated by
1304+-- path is in JSONB object, new_value will be inserted only if target does not
1305+-- exist. As with the path orientated operators, negative integers that appear
1306+-- in path count from the end of JSON arrays.
1307+jsonbInsert
1308+ :: PGtextArray "jsonbInsert" arr
1309+ => Expression schema relations grouping params (nullity 'PGjsonb)
1310+ -> Expression schema relations grouping params (nullity arr)
1311+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1312+ -> Maybe (Expression schema relations grouping params (nullity 'PGbool))
1313+ -> Expression schema relations grouping params (nullity 'PGjsonb)
1314+jsonbInsert tgt path val insertAfter = case insertAfter of
1315+ Just i -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* i :* Nil)
1316+ Nothing -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* Nil)
1317+
1318+-- | Returns its argument as indented JSON text.
1319+jsonbPretty
1320+ :: Expression schema relations grouping params (nullity 'PGjsonb)
1321+ -> Expression schema relations grouping params (nullity 'PGtext)
1322+jsonbPretty = unsafeFunction "jsonb_pretty"
1323+
1324+{-----------------------------------------
1325+aggregation
1326+-----------------------------------------}
1327+
1328+-- | escape hatch to define aggregate functions
1329+unsafeAggregate
1330+ :: ByteString -- ^ aggregate function
1331+ -> Expression schema relations 'Ungrouped params (xty)
1332+ -> Expression schema relations ('Grouped bys) params (yty)
1333+unsafeAggregate fun x = UnsafeExpression $ mconcat
1334+ [fun, "(", renderExpression x, ")"]
1335+
1336+-- | escape hatch to define aggregate functions over distinct values
1337+unsafeAggregateDistinct
1338+ :: ByteString -- ^ aggregate function
1339+ -> Expression schema relations 'Ungrouped params (xty)
1340+ -> Expression schema relations ('Grouped bys) params (yty)
1341+unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat
1342+ [fun, "(DISTINCT ", renderExpression x, ")"]
1343+
1344+-- | >>> :{
1345+-- let
1346+-- expression :: Expression schema '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Grouped bys) params ('Null 'PGnumeric)
1347+-- expression = sum_ #col
1348+-- in printSQL expression
1349+-- :}
1350+-- sum("col")
1351+sum_
1352+ :: PGNum ty
1353+ => Expression schema relations 'Ungrouped params (nullity ty)
1354+ -- ^ what to sum
1355+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1356+sum_ = unsafeAggregate "sum"
1357+
1358+-- | >>> :{
1359+-- let
1360+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGnumeric]] ('Grouped bys) params (nullity 'PGnumeric)
1361+-- expression = sumDistinct #col
1362+-- in printSQL expression
1363+-- :}
1364+-- sum(DISTINCT "col")
1365+sumDistinct
1366+ :: PGNum ty
1367+ => Expression schema relations 'Ungrouped params (nullity ty)
1368+ -- ^ what to sum
1369+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1370+sumDistinct = unsafeAggregateDistinct "sum"
1371+
1372+-- | A constraint for `PGType`s that you can take averages of and the resulting
1373+-- `PGType`.
1374+class PGAvg ty avg | ty -> avg where
1375+ avg, avgDistinct
1376+ :: Expression schema relations 'Ungrouped params (nullity ty)
1377+ -- ^ what to average
1378+ -> Expression schema relations ('Grouped bys) params (nullity avg)
1379+ avg = unsafeAggregate "avg"
1380+ avgDistinct = unsafeAggregateDistinct "avg"
1381+instance PGAvg 'PGint2 'PGnumeric
1382+instance PGAvg 'PGint4 'PGnumeric
1383+instance PGAvg 'PGint8 'PGnumeric
1384+instance PGAvg 'PGnumeric 'PGnumeric
1385+instance PGAvg 'PGfloat4 'PGfloat8
1386+instance PGAvg 'PGfloat8 'PGfloat8
1387+instance PGAvg 'PGinterval 'PGinterval
1388+
1389+-- | >>> :{
1390+-- let
1391+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1392+-- expression = bitAnd #col
1393+-- in printSQL expression
1394+-- :}
1395+-- bit_and("col")
1396+bitAnd
1397+ :: PGIntegral int
1398+ => Expression schema relations 'Ungrouped params (nullity int)
1399+ -- ^ what to aggregate
1400+ -> Expression schema relations ('Grouped bys) params (nullity int)
1401+bitAnd = unsafeAggregate "bit_and"
1402+
1403+-- | >>> :{
1404+-- let
1405+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1406+-- expression = bitOr #col
1407+-- in printSQL expression
1408+-- :}
1409+-- bit_or("col")
1410+bitOr
1411+ :: PGIntegral int
1412+ => Expression schema relations 'Ungrouped params (nullity int)
1413+ -- ^ what to aggregate
1414+ -> Expression schema relations ('Grouped bys) params (nullity int)
1415+bitOr = unsafeAggregate "bit_or"
1416+
1417+-- | >>> :{
1418+-- let
1419+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1420+-- expression = bitAndDistinct #col
1421+-- in printSQL expression
1422+-- :}
1423+-- bit_and(DISTINCT "col")
1424+bitAndDistinct
1425+ :: PGIntegral int
1426+ => Expression schema relations 'Ungrouped params (nullity int)
1427+ -- ^ what to aggregate
1428+ -> Expression schema relations ('Grouped bys) params (nullity int)
1429+bitAndDistinct = unsafeAggregateDistinct "bit_and"
1430+
1431+-- | >>> :{
1432+-- let
1433+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)
1434+-- expression = bitOrDistinct #col
1435+-- in printSQL expression
1436+-- :}
1437+-- bit_or(DISTINCT "col")
1438+bitOrDistinct
1439+ :: PGIntegral int
1440+ => Expression schema relations 'Ungrouped params (nullity int)
1441+ -- ^ what to aggregate
1442+ -> Expression schema relations ('Grouped bys) params (nullity int)
1443+bitOrDistinct = unsafeAggregateDistinct "bit_or"
1444+
1445+-- | >>> :{
1446+-- let
1447+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1448+-- expression = boolAnd #col
1449+-- in printSQL expression
1450+-- :}
1451+-- bool_and("col")
1452+boolAnd
1453+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1454+ -- ^ what to aggregate
1455+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1456+boolAnd = unsafeAggregate "bool_and"
1457+
1458+-- | >>> :{
1459+-- let
1460+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1461+-- expression = boolOr #col
1462+-- in printSQL expression
1463+-- :}
1464+-- bool_or("col")
1465+boolOr
1466+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1467+ -- ^ what to aggregate
1468+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1469+boolOr = unsafeAggregate "bool_or"
1470+
1471+-- | >>> :{
1472+-- let
1473+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1474+-- expression = boolAndDistinct #col
1475+-- in printSQL expression
1476+-- :}
1477+-- bool_and(DISTINCT "col")
1478+boolAndDistinct
1479+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1480+ -- ^ what to aggregate
1481+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1482+boolAndDistinct = unsafeAggregateDistinct "bool_and"
1483+
1484+-- | >>> :{
1485+-- let
1486+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1487+-- expression = boolOrDistinct #col
1488+-- in printSQL expression
1489+-- :}
1490+-- bool_or(DISTINCT "col")
1491+boolOrDistinct
1492+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1493+ -- ^ what to aggregate
1494+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1495+boolOrDistinct = unsafeAggregateDistinct "bool_or"
1496+
1497+-- | A special aggregation that does not require an input
1498+--
1499+-- >>> printSQL countStar
1500+-- count(*)
1501+countStar
1502+ :: Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1503+countStar = UnsafeExpression $ "count(*)"
1504+
1505+-- | >>> :{
1506+-- let
1507+-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)
1508+-- expression = count #col
1509+-- in printSQL expression
1510+-- :}
1511+-- count("col")
1512+count
1513+ :: Expression schema relations 'Ungrouped params ty
1514+ -- ^ what to count
1515+ -> Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1516+count = unsafeAggregate "count"
1517+
1518+-- | >>> :{
1519+-- let
1520+-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)
1521+-- expression = countDistinct #col
1522+-- in printSQL expression
1523+-- :}
1524+-- count(DISTINCT "col")
1525+countDistinct
1526+ :: Expression schema relations 'Ungrouped params ty
1527+ -- ^ what to count
1528+ -> Expression schema relations ('Grouped bys) params ('NotNull 'PGint8)
1529+countDistinct = unsafeAggregateDistinct "count"
1530+
1531+-- | synonym for `boolAnd`
1532+--
1533+-- >>> :{
1534+-- let
1535+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1536+-- expression = every #col
1537+-- in printSQL expression
1538+-- :}
1539+-- every("col")
1540+every
1541+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1542+ -- ^ what to aggregate
1543+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1544+every = unsafeAggregate "every"
1545+
1546+-- | synonym for `boolAndDistinct`
1547+--
1548+-- >>> :{
1549+-- let
1550+-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)
1551+-- expression = everyDistinct #col
1552+-- in printSQL expression
1553+-- :}
1554+-- every(DISTINCT "col")
1555+everyDistinct
1556+ :: Expression schema relations 'Ungrouped params (nullity 'PGbool)
1557+ -- ^ what to aggregate
1558+ -> Expression schema relations ('Grouped bys) params (nullity 'PGbool)
1559+everyDistinct = unsafeAggregateDistinct "every"
1560+
1561+-- | minimum and maximum aggregation
1562+max_, min_, maxDistinct, minDistinct
1563+ :: Expression schema relations 'Ungrouped params (nullity ty)
1564+ -- ^ what to aggregate
1565+ -> Expression schema relations ('Grouped bys) params (nullity ty)
1566+max_ = unsafeAggregate "max"
1567+min_ = unsafeAggregate "min"
1568+maxDistinct = unsafeAggregateDistinct "max"
1569+minDistinct = unsafeAggregateDistinct "min"
1570+
1571+{-----------------------------------------
1572+type expressions
1573+-----------------------------------------}
1574+
1575+-- | `TypeExpression`s are used in `cast`s and `createTable` commands.
1576+newtype TypeExpression (schema :: SchemaType) (ty :: PGType)
1577+ = UnsafeTypeExpression { renderTypeExpression :: ByteString }
1578+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
1579+
1580+instance (Has alias schema ('Typedef ty))
1581+ => IsLabel alias (TypeExpression schema ty) where
1582+ fromLabel = UnsafeTypeExpression (renderAlias (fromLabel @alias))
1583+
1584+-- | logical Boolean (true/false)
1585+bool :: TypeExpression schema 'PGbool
1586+bool = UnsafeTypeExpression "bool"
1587+-- | signed two-byte integer
1588+int2, smallint :: TypeExpression schema 'PGint2
1589+int2 = UnsafeTypeExpression "int2"
1590+smallint = UnsafeTypeExpression "smallint"
1591+-- | signed four-byte integer
1592+int4, int, integer :: TypeExpression schema 'PGint4
1593+int4 = UnsafeTypeExpression "int4"
1594+int = UnsafeTypeExpression "int"
1595+integer = UnsafeTypeExpression "integer"
1596+-- | signed eight-byte integer
1597+int8, bigint :: TypeExpression schema 'PGint8
1598+int8 = UnsafeTypeExpression "int8"
1599+bigint = UnsafeTypeExpression "bigint"
1600+-- | arbitrary precision numeric type
1601+numeric :: TypeExpression schema 'PGnumeric
1602+numeric = UnsafeTypeExpression "numeric"
1603+-- | single precision floating-point number (4 bytes)
1604+float4, real :: TypeExpression schema 'PGfloat4
1605+float4 = UnsafeTypeExpression "float4"
1606+real = UnsafeTypeExpression "real"
1607+-- | double precision floating-point number (8 bytes)
1608+float8, doublePrecision :: TypeExpression schema 'PGfloat8
1609+float8 = UnsafeTypeExpression "float8"
1610+doublePrecision = UnsafeTypeExpression "double precision"
1611+-- | variable-length character string
1612+text :: TypeExpression schema 'PGtext
1613+text = UnsafeTypeExpression "text"
1614+-- | fixed-length character string
1615+char, character
1616+ :: (KnownNat n, 1 <= n)
1617+ => proxy n
1618+ -> TypeExpression schema ('PGchar n)
1619+char p = UnsafeTypeExpression $ "char(" <> renderNat p <> ")"
1620+character p = UnsafeTypeExpression $ "character(" <> renderNat p <> ")"
1621+-- | variable-length character string
1622+varchar, characterVarying
1623+ :: (KnownNat n, 1 <= n)
1624+ => proxy n
1625+ -> TypeExpression schema ('PGvarchar n)
1626+varchar p = UnsafeTypeExpression $ "varchar(" <> renderNat p <> ")"
1627+characterVarying p = UnsafeTypeExpression $
1628+ "character varying(" <> renderNat p <> ")"
1629+-- | binary data ("byte array")
1630+bytea :: TypeExpression schema 'PGbytea
1631+bytea = UnsafeTypeExpression "bytea"
1632+-- | date and time (no time zone)
1633+timestamp :: TypeExpression schema 'PGtimestamp
1634+timestamp = UnsafeTypeExpression "timestamp"
1635+-- | date and time, including time zone
1636+timestampWithTimeZone :: TypeExpression schema 'PGtimestamptz
1637+timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"
1638+-- | calendar date (year, month, day)
1639+date :: TypeExpression schema 'PGdate
1640+date = UnsafeTypeExpression "date"
1641+-- | time of day (no time zone)
1642+time :: TypeExpression schema 'PGtime
1643+time = UnsafeTypeExpression "time"
1644+-- | time of day, including time zone
1645+timeWithTimeZone :: TypeExpression schema 'PGtimetz
1646+timeWithTimeZone = UnsafeTypeExpression "time with time zone"
1647+-- | time span
1648+interval :: TypeExpression schema 'PGinterval
1649+interval = UnsafeTypeExpression "interval"
1650+-- | universally unique identifier
1651+uuid :: TypeExpression schema 'PGuuid
1652+uuid = UnsafeTypeExpression "uuid"
1653+-- | IPv4 or IPv6 host address
1654+inet :: TypeExpression schema 'PGinet
1655+inet = UnsafeTypeExpression "inet"
1656+-- | textual JSON data
1657+json :: TypeExpression schema 'PGjson
1658+json = UnsafeTypeExpression "json"
1659+-- | binary JSON data, decomposed
1660+jsonb :: TypeExpression schema 'PGjsonb
1661+jsonb = UnsafeTypeExpression "jsonb"
1662+-- | variable length array
1663+vararray
1664+ :: TypeExpression schema pg
1665+ -> TypeExpression schema ('PGvararray pg)
1666+vararray ty = UnsafeTypeExpression $ renderTypeExpression ty <> "[]"
1667+-- | fixed length array
1668+--
1669+-- >>> renderTypeExpression (fixarray (Proxy @2) json)
1670+-- "json[2]"
1671+fixarray
1672+ :: KnownNat n
1673+ => proxy n
1674+ -> TypeExpression schema pg
1675+ -> TypeExpression schema ('PGfixarray n pg)
1676+fixarray p ty = UnsafeTypeExpression $
1677+ renderTypeExpression ty <> "[" <> renderNat p <> "]"
1678+
1679+-- | `pgtype` is a demoted version of a `PGType`
1680+class PGTyped schema (ty :: PGType) where pgtype :: TypeExpression schema ty
1681+instance PGTyped schema 'PGbool where pgtype = bool
1682+instance PGTyped schema 'PGint2 where pgtype = int2
1683+instance PGTyped schema 'PGint4 where pgtype = int4
1684+instance PGTyped schema 'PGint8 where pgtype = int8
1685+instance PGTyped schema 'PGnumeric where pgtype = numeric
1686+instance PGTyped schema 'PGfloat4 where pgtype = float4
1687+instance PGTyped schema 'PGfloat8 where pgtype = float8
1688+instance PGTyped schema 'PGtext where pgtype = text
1689+instance (KnownNat n, 1 <= n)
1690+ => PGTyped schema ('PGchar n) where pgtype = char (Proxy @n)
1691+instance (KnownNat n, 1 <= n)
1692+ => PGTyped schema ('PGvarchar n) where pgtype = varchar (Proxy @n)
1693+instance PGTyped schema 'PGbytea where pgtype = bytea
1694+instance PGTyped schema 'PGtimestamp where pgtype = timestamp
1695+instance PGTyped schema 'PGtimestamptz where pgtype = timestampWithTimeZone
1696+instance PGTyped schema 'PGdate where pgtype = date
1697+instance PGTyped schema 'PGtime where pgtype = time
1698+instance PGTyped schema 'PGtimetz where pgtype = timeWithTimeZone
1699+instance PGTyped schema 'PGinterval where pgtype = interval
1700+instance PGTyped schema 'PGuuid where pgtype = uuid
1701+instance PGTyped schema 'PGjson where pgtype = json
1702+instance PGTyped schema 'PGjsonb where pgtype = jsonb
1703+instance PGTyped schema ty => PGTyped schema ('PGvararray ty) where
1704+ pgtype = vararray (pgtype @schema @ty)
1705+instance (KnownNat n, PGTyped schema ty) => PGTyped schema ('PGfixarray n ty) where
1706+ 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+339−410
@@ -11,139 +11,84 @@ Squeal data manipulation language.
1111{-# LANGUAGE
1212 DeriveGeneric
1313 , FlexibleContexts
14− , FlexibleInstances
1514 , GADTs
1615 , GeneralizedNewtypeDeriving
1716 , LambdaCase
18− , MultiParamTypeClasses
1917 , OverloadedStrings
20− , PatternSynonyms
21− , QuantifiedConstraints
2218 , RankNTypes
23− , ScopedTypeVariables
24− , TypeApplications
25− , TypeFamilies
2619 , TypeInType
2720 , TypeOperators
28− , UndecidableInstances
2921#-}
3022
3123module Squeal.PostgreSQL.Manipulation
3224 ( -- * Manipulation
33− Manipulation_
34− , Manipulation (..)
25+ Manipulation (UnsafeManipulation, renderManipulation)
3526 , queryStatement
27+ , ColumnValue (..)
28+ , ReturningClause (ReturningStar, Returning)
29+ , ConflictClause (OnConflictDoRaise, OnConflictDoNothing, OnConflictDoUpdate)
3630 -- * Insert
37− , insertInto
38− , insertInto_
31+ , insertRows
32+ , insertRow
33+ , insertRows_
34+ , insertRow_
35+ , insertQuery
36+ , insertQuery_
37+ , renderReturningClause
38+ , renderConflictClause
3939 -- * Update
4040 , update
4141 , update_
4242 -- * Delete
4343 , deleteFrom
4444 , deleteFrom_
45− -- * Clauses
46− , Optional (..)
47− , QueryClause (..)
48− , pattern Values_
49− , ReturningClause (..)
50− , pattern Returning_
51− , ConflictClause (..)
52− , ConflictTarget (..)
53− , ConflictAction (..)
54− , UsingClause (..)
45+ -- * With
46+ , with
5547 ) where
5648
5749import Control.DeepSeq
5850import Data.ByteString hiding (foldr)
59−import Data.Kind (Type)
51+import Data.Monoid
6052
6153import qualified Generics.SOP as SOP
6254import qualified GHC.Generics as GHC
6355
64−import Squeal.PostgreSQL.Alias
6556import Squeal.PostgreSQL.Expression
66−import Squeal.PostgreSQL.Expression.Logic
67−import Squeal.PostgreSQL.List
68−import Squeal.PostgreSQL.PG
6957import Squeal.PostgreSQL.Render
7058import Squeal.PostgreSQL.Query
7159import Squeal.PostgreSQL.Schema
7260
73−-- $setup
74−-- >>> import Squeal.PostgreSQL
75−-- >>> import Data.Int
76−-- >>> import Data.Time
77−
7861{- |
7962A `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.
8164A `Query` is also considered a `Manipulation` even though it does not modify data.
8265
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−
12566simple insert:
12667
127−>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]
128−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
12968>>> :{
13069let
131− manipulation :: Manipulation_ (Public Schema) () ()
70+ manipulation :: Manipulation
71+ '[ "tab" ::: 'Table ('[] :=>
72+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
73+ , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[] '[]
13274 manipulation =
133− insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))
75+ insertRow_ #tab (Set 2 `as` #col1 :* Default `as` #col2)
13476in printSQL manipulation
13577:}
13678INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)
13779
13880parameterized insert:
13981
140−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]
141−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
14282>>> :{
14383let
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 ] '[]
14589 manipulation =
146− insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))
90+ insertRow_ #tab
91+ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2)
14792in printSQL manipulation
14893:}
14994INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))
@@ -152,48 +97,71 @@ returning insert:
15297
15398>>> :{
15499let
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]
156105 manipulation =
157− insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))
106+ insertRow #tab (Set 2 `as` #col1 :* Default `as` #col2)
158107 OnConflictDoRaise (Returning (#col1 `as` #fromOnly))
159108in printSQL manipulation
160109:}
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"
162111
163112upsert:
164113
165−>>> type CustomersColumns = '["name" ::: 'NoDef :=> 'NotNull 'PGtext, "email" ::: 'NoDef :=> 'NotNull 'PGtext]
166−>>> type CustomersConstraints = '["uq" ::: 'Unique '["name"]]
167−>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]
168114>>> :{
169115let
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]
171121 manipulation =
172− insertInto #customers
173− (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))
174− (OnConflict (OnConstraint #uq)
175− (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))
176− (Returning_ Nil)
122+ insertRows #tab
123+ (Set 2 `as` #col1 :* Set 4 `as` #col2)
124+ [Set 6 `as` #col1 :* Set 8 `as` #col2]
125+ (OnConflictDoUpdate
126+ (Set 2 `as` #col1 :* Same `as` #col2)
127+ [#col1 .== #col2])
128+ (Returning $ (#col1 + #col2) `as` #sum)
177129in printSQL manipulation
178130:}
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"
180132
181133query insert:
182134
183135>>> :{
184136let
185− manipulation :: Manipulation_ (Public Schema) () ()
186− manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))
137+ manipulation :: Manipulation
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))))
187150in printSQL manipulation
188151:}
189−INSERT INTO "tab" SELECT * FROM "tab" AS "tab"
152+INSERT INTO "tab" SELECT * FROM "other_tab" AS "t"
190153
191154update:
192155
193156>>> :{
194157let
195− manipulation :: Manipulation_ (Public Schema) () ()
196− manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)
158+ manipulation :: Manipulation
159+ '[ "tab" ::: 'Table ('[] :=>
160+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
161+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[] '[]
162+ manipulation =
163+ update_ #tab (Set 2 `as` #col1 :* Same `as` #col2)
164+ (#col1 ./= #col2)
197165in printSQL manipulation
198166:}
199167UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")
@@ -202,178 +170,154 @@ delete:
202170
203171>>> :{
204172let
205− manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)
206− manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)
173+ manipulation :: Manipulation
174+ '[ "tab" ::: 'Table ('[] :=>
175+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
176+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[]
177+ '[ "col1" ::: 'NotNull 'PGint4
178+ , "col2" ::: 'NotNull 'PGint4 ]
179+ manipulation = deleteFrom #tab (#col1 .== #col2) ReturningStar
207180in printSQL manipulation
208181:}
209182DELETE 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"
245183-}
246−type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where
247− Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)
184+newtype Manipulation
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
248193
249194-- | Convert a `Query` into a `Manipulation`.
250195queryStatement
251− :: Query '[] commons schemas params columns
252− -- ^ `Query` to embed as a `Manipulation`
253− -> Manipulation commons schemas params columns
254−queryStatement q = UnsafeManipulation $ renderSQL q
196+ :: Query schema params columns
197+ -> Manipulation schema params columns
198+queryStatement q = UnsafeManipulation $ renderQuery q
255199
256200{-----------------------------------------
257201INSERT statements
258202-----------------------------------------}
259203
260−{- |
261−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
263−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.
265−Even if you know only some column values, a complete row must be created.
266−-}
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
273− , SOP.SListI row1 )
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
204+-- | Insert multiple rows.
205+--
206+-- When a table is created, it contains no data. The first thing to do
207+-- before a database can be of much use is to insert data. Data is
208+-- conceptually inserted one row at a time. Of course you can also insert
209+-- more than one row, but there is no way to insert less than one row.
210+-- Even if you know only some column values, a complete row must be created.
211+insertRows
212+ :: ( SOP.SListI columns
213+ , SOP.SListI results
292214 , Has tab schema ('Table table)
293− , 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
300− -> Manipulation commons schemas params '[]
301−insertInto_ tab qry =
302− insertInto tab qry OnConflictDoRaise (Returning_ Nil)
303−
304−-- | A `QueryClause` describes what to `insertInto` a table.
305−data QueryClause commons schemas params columns where
306− Values
307− :: SOP.SListI columns
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)
330− <+> "VALUES"
331− <+> commaSeparated
332− ( parenthesized
333− . renderCommaSeparated renderValuePart <$> row0 : rows )
334− Select row0 tab ->
335− parenthesized (renderCommaSeparatedMaybe renderSQLPartMaybe row0)
336− <+> "SELECT"
337− <+> renderCommaSeparatedMaybe renderValuePartMaybe row0
338− <+> renderSQL tab
339− Subquery qry -> renderQuery qry
215+ , columns ~ TableToColumns table )
216+ => Alias tab -- ^ table to insert into
217+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
218+ -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert
219+ -> ConflictClause schema columns params
220+ -- ^ what to do in case of constraint conflict
221+ -> ReturningClause schema columns params results -- ^ results to return
222+ -> Manipulation schema params results
223+insertRows tab rw rws conflict returning = UnsafeManipulation $
224+ "INSERT" <+> "INTO" <+> renderAlias tab
225+ <+> parenthesized (renderCommaSeparated renderAliasPart rw)
226+ <+> "VALUES"
227+ <+> commaSeparated
228+ ( parenthesized
229+ . renderCommaSeparated renderColumnValuePart <$> rw:rws )
230+ <> renderConflictClause conflict
231+ <> renderReturningClause returning
340232 where
341− renderSQLPartMaybe, renderValuePartMaybe
342− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
343− -> Maybe ByteString
344− renderSQLPartMaybe = \case
345− Default `As` _ -> Nothing
346− Set _ `As` name -> Just $ renderSQL name
347− renderValuePartMaybe = \case
348− Default `As` _ -> Nothing
349− Set value `As` _ -> Just $ renderExpression value
350− renderSQLPart, renderValuePart
351− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
352− -> ByteString
353− renderSQLPart (_ `As` name) = renderSQL name
354− renderValuePart (value `As` _) = renderSQL value
355−
356−-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s
357−-- whose `ColumnsType` must match the tables'.
358−pattern Values_
359− :: SOP.SListI columns
360− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns
361− -- ^ row of values
362− -> QueryClause commons schemas params columns
363−pattern Values_ vals = Values vals []
364−
365−-- | `Optional` is either `Default` or a value, parameterized by an appropriate
366−-- `ColumnConstraint`.
367−data Optional expr ty where
368− -- | Use the `Default` value for a column.
369− Default :: Optional expr ('Def :=> ty)
370− -- | `Set` a value for a column.
371− Set :: expr ty -> Optional expr (def :=> ty)
372−
373−instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where
374− renderSQL = \case
375− Default -> "DEFAULT"
376− Set expr -> renderSQL expr
233+ renderAliasPart, renderColumnValuePart
234+ :: Aliased (ColumnValue schema '[] params) ty -> ByteString
235+ renderAliasPart (_ `As` name) = renderAlias name
236+ renderColumnValuePart (value `As` _) = case value of
237+ Default -> "DEFAULT"
238+ Set expression -> renderExpression expression
239+
240+-- | Insert a single row.
241+insertRow
242+ :: ( SOP.SListI columns
243+ , SOP.SListI results
244+ , Has tab schema ('Table table)
245+ , columns ~ TableToColumns table )
246+ => Alias tab -- ^ table to insert into
247+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
248+ -> ConflictClause schema columns params
249+ -- ^ what to do in case of constraint conflict
250+ -> ReturningClause schema columns params results -- ^ results to return
251+ -> Manipulation schema params results
252+insertRow tab rw = insertRows tab rw []
253+
254+-- | Insert multiple rows returning `Nil` and raising an error on conflicts.
255+insertRows_
256+ :: ( SOP.SListI columns
257+ , Has tab schema ('Table table)
258+ , columns ~ TableToColumns table )
259+ => Alias tab -- ^ table to insert into
260+ -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert
261+ -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert
262+ -> Manipulation schema params '[]
263+insertRows_ tab rw rws =
264+ insertRows tab rw rws OnConflictDoRaise (Returning Nil)
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)
377321
378322-- | A `ReturningClause` computes and return value(s) based
379323-- 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
381325-- serial sequence number. However, any expression using the table's columns
382326-- is allowed. Only rows that were successfully inserted or updated or
383327-- deleted will be returned. For example, if a row was locked
384−-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,
385−-- the row will not be returned. `Returning` `Star` will return all columns
386−-- in the row. Use `Returning` `Nil` in the common case where no return
328+-- but not updated because an `OnConflictDoUpdate` condition was not satisfied,
329+-- the row will not be returned. `ReturningStar` will return all columns
330+-- in the row. Use @Returning Nil@ in the common case where no return
387331-- values are desired.
388−newtype ReturningClause commons schemas params from row =
389− Returning (Selection '[] commons 'Ungrouped schemas params from row)
390−
391−instance RenderSQL (ReturningClause commons schemas params from row) where
392− renderSQL = \case
393− Returning (List Nil) -> ""
394− Returning selection -> " RETURNING" <+> renderSQL selection
395−
396−-- | `Returning` a `List`
397−pattern Returning_
398− :: SOP.SListI row
399− => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row
400− -- ^ row of values
401− -> ReturningClause commons schemas params from row
402−pattern Returning_ list = Returning (List list)
332+data ReturningClause
333+ (schema :: SchemaType)
334+ (columns :: ColumnsType)
335+ (params :: [NullityType])
336+ (results :: RelationType)
337+ where
338+ ReturningStar
339+ :: results ~ ColumnsToRelation columns
340+ => ReturningClause schema columns params results
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
348+ :: SOP.SListI results
349+ => ReturningClause schema params columns results
350+ -> ByteString
351+renderReturningClause = \case
352+ ReturningStar -> " RETURNING *"
353+ Returning Nil -> ""
354+ Returning results -> " RETURNING"
355+ <+> renderCommaSeparated (renderAliasedAs renderExpression) results
403356
404357-- | A `ConflictClause` specifies an action to perform upon a constraint
405358-- violation. `OnConflictDoRaise` will raise an error.
406−-- `OnConflict` `DoNothing` simply avoids inserting a row.
407−-- `OnConflict` `DoUpdate` updates the existing row that conflicts with the row
359+-- `OnConflictDoNothing` simply avoids inserting a row.
360+-- `OnConflictDoUpdate` updates the existing row that conflicts with the row
408361-- proposed for insertion.
409−data ConflictClause tab commons schemas params table where
410− OnConflictDoRaise :: ConflictClause tab commons schemas params table
411− OnConflict
412− :: ConflictTarget constraints
413− -- ^ conflict target
414− -> ConflictAction tab commons schemas params columns
415− -- ^ conflict action
416− -> ConflictClause tab commons schemas params (constraints :=> columns)
362+data ConflictClause (schema :: SchemaType) (columns :: ColumnsType) params where
363+ OnConflictDoRaise :: ConflictClause schema columns params
364+ OnConflictDoNothing :: ConflictClause schema columns params
365+ OnConflictDoUpdate
366+ :: NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
367+ -> [Condition schema '[table ::: ColumnsToRelation columns] 'Ungrouped params]
368+ -> ConflictClause schema columns params
417369
418370-- | Render a `ConflictClause`.
419−instance SOP.SListI (TableToColumns table)
420− => RenderSQL (ConflictClause tab commons schemas params table) where
421− renderSQL = \case
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
371+renderConflictClause
372+ :: SOP.SListI columns
373+ => ConflictClause schema columns params
463374 -> ByteString
464−renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr
465−
466−-- | A `ConflictTarget` specifies the constraint violation that triggers a
467−-- `ConflictAction`.
468−data ConflictTarget constraints where
469− OnConstraint
470− :: Has con constraints constraint
471− => Alias con
472− -> ConflictTarget constraints
473−
474−-- | Render a `ConflictTarget`
475−instance RenderSQL (ConflictTarget constraints) where
476− renderSQL (OnConstraint con) =
477− "ON" <+> "CONSTRAINT" <+> renderSQL con
375+renderConflictClause = \case
376+ OnConflictDoRaise -> ""
377+ OnConflictDoNothing -> " ON CONFLICT DO NOTHING"
378+ OnConflictDoUpdate updates whs'
379+ -> " ON CONFLICT DO UPDATE SET"
380+ <+> renderCommaSeparatedMaybe renderUpdate updates
381+ <> case whs' of
382+ [] -> ""
383+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)
384+ where
385+ renderUpdate
386+ :: Aliased (ColumnValue schema columns params) column
387+ -> Maybe ByteString
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
478394
479395{-----------------------------------------
480396UPDATE statements
@@ -484,95 +400,108 @@ UPDATE statements
484400-- in all rows that satisfy the condition.
485401update
486402 :: ( SOP.SListI columns
487− , SOP.SListI row1
488− , Has sch schemas schema
403+ , SOP.SListI results
489404 , Has tab schema ('Table table)
490− , row0 ~ TableToRow table
491− , columns ~ TableToColumns table
492− , SOP.All (HasIn columns) subcolumns
493− , AllUnique subcolumns )
494− => QualifiedAlias sch tab -- ^ table to update
495− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns
405+ , columns ~ TableToColumns table )
406+ => Alias tab -- ^ table to update
407+ -> NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
496408 -- ^ modified values to replace old values
497− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]
409+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
498410 -- ^ condition under which to perform update on a row
499− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
500− -> Manipulation commons schemas params row1
411+ -> ReturningClause schema columns params results -- ^ results to return
412+ -> Manipulation schema params results
501413update tab columns wh returning = UnsafeManipulation $
502414 "UPDATE"
503− <+> renderSQL tab
415+ <+> renderAlias tab
504416 <+> "SET"
505− <+> renderCommaSeparated renderUpdate columns
506− <+> "WHERE" <+> renderSQL wh
507− <> renderSQL returning
417+ <+> renderCommaSeparatedMaybe renderUpdate columns
418+ <+> "WHERE" <+> renderExpression wh
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
508430
509431-- | Update a row returning `Nil`.
510432update_
511433 :: ( SOP.SListI columns
512− , Has sch schemas schema
513434 , Has tab schema ('Table table)
514− , row ~ TableToRow table
515− , columns ~ TableToColumns table
516− , SOP.All (HasIn columns) subcolumns
517− , AllUnique subcolumns )
518− => QualifiedAlias sch tab -- ^ table to update
519− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns
435+ , columns ~ TableToColumns table )
436+ => Alias tab -- ^ table to update
437+ -> NP (Aliased (ColumnValue schema (ColumnsToRelation columns) params)) columns
520438 -- ^ modified values to replace old values
521− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
439+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
522440 -- ^ condition under which to perform update on a row
523− -> Manipulation commons schemas params '[]
524−update_ tab columns wh = update tab columns wh (Returning_ Nil)
441+ -> Manipulation schema params '[]
442+update_ tab columns wh = update tab columns wh (Returning Nil)
525443
526444{-----------------------------------------
527445DELETE statements
528446-----------------------------------------}
529447
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.
547449deleteFrom
548− :: ( SOP.SListI row1
549− , Has sch schemas schema
450+ :: ( SOP.SListI results
550451 , Has tab schema ('Table table)
551− , row0 ~ TableToRow table
552452 , columns ~ TableToColumns table )
553− => QualifiedAlias sch tab -- ^ table to delete from
554− -> UsingClause commons schemas params from
555− -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)
453+ => Alias tab -- ^ table to delete from
454+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
556455 -- ^ condition under which to delete a row
557− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
558− -> Manipulation commons schemas params row1
559−deleteFrom tab using wh returning = UnsafeManipulation $
560− "DELETE FROM"
561− <+> renderSQL tab
562− <> case using of
563− NoUsing -> ""
564− Using tables -> " USING" <+> renderSQL tables
565− <+> "WHERE" <+> renderSQL wh
566− <> renderSQL returning
456+ -> ReturningClause schema columns params results -- ^ results to return
457+ -> Manipulation schema params results
458+deleteFrom tab wh returning = UnsafeManipulation $
459+ "DELETE FROM" <+> renderAlias tab
460+ <+> "WHERE" <+> renderExpression wh
461+ <> renderReturningClause returning
567462
568463-- | Delete rows returning `Nil`.
569464deleteFrom_
570− :: ( Has sch schemas schema
571− , Has tab schema ('Table table)
572− , row ~ TableToRow table
465+ :: ( Has tab schema ('Table table)
573466 , columns ~ TableToColumns table )
574− => QualifiedAlias sch tab -- ^ table to delete from
575− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
467+ => Alias tab -- ^ table to delete from
468+ -> Condition schema '[tab ::: ColumnsToRelation columns] 'Ungrouped params
576469 -- ^ condition under which to delete a row
577− -> Manipulation commons schemas params '[]
578−deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)
470+ -> Manipulation schema params '[]
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)
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)) (common ': commons)
495+ -- ^ common table expressions
496+ -> Manipulation (With (common ': 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+206−338
@@ -8,13 +8,8 @@ Stability: experimental
88This module defines a `Migration` type to safely
99change the schema of your database over time. Let's see an example!
1010
11−First turn on some extensions.
12−
1311>>> :set -XDataKinds -XOverloadedLabels
1412>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators
15−
16−Next, let's define our `TableType`s.
17−
1813>>> :{
1914type UsersTable =
2015 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
@@ -25,7 +20,7 @@ type UsersTable =
2520
2621>>> :{
2722type EmailsTable =
28− '[ "pk_emails" ::: 'PrimaryKey '["id"]
23+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
2924 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
3025 ] :=>
3126 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
@@ -34,293 +29,248 @@ type EmailsTable =
3429 ]
3530:}
3631
37−Now we can define some `Migration`s to make our tables.
38−
3932>>> :{
4033let
41− makeUsers :: Migration Definition (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]
34+ makeUsers :: Migration IO '[] '["users" ::: 'Table UsersTable]
4235 makeUsers = Migration
4336 { name = "make users table"
44− , up = createTable #users
37+ , up = void . define $
38+ createTable #users
4539 ( serial `as` #id :*
46− notNullable text `as` #name )
40+ (text & notNullable) `as` #name )
4741 ( primaryKey #id `as` #pk_users )
48− , down = dropTable #users
42+ , down = void . define $ dropTable #users
4943 }
5044:}
5145
5246>>> :{
5347let
54− makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]
55− '["public" ::: '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]]
48+ makeEmails :: Migration IO '["users" ::: 'Table UsersTable]
49+ '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]
5650 makeEmails = Migration
5751 { name = "make emails table"
58− , up = createTable #emails
52+ , up = void . define $
53+ createTable #emails
5954 ( serial `as` #id :*
60− notNullable int `as` #user_id :*
61− nullable text `as` #email )
55+ (int & notNullable) `as` #user_id :*
56+ (text & nullable) `as` #email )
6257 ( primaryKey #id `as` #pk_emails :*
6358 foreignKey #user_id #users #id
6459 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
65− , down = dropTable #emails
60+ , down = void . define $ dropTable #emails
6661 }
6762:}
6863
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.
7065
7166>>> let migrations = makeUsers :>> makeEmails :>> Done
7267
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+:}
7478
75−>>> import Control.Monad.IO.Class
7679>>> :{
7780withConnection "host=localhost port=5432 dbname=exampledb" $
7881 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
7982 -- suppress notices
80− & pqThen (liftIO (putStrLn "Migrate"))
8183 & pqThen (migrateUp migrations)
82− & pqThen (liftIO (putStrLn "Rollback"))
84+ & pqThen numMigrations
8385 & pqThen (migrateDown migrations)
86+ & pqThen numMigrations
8487:}
85−Migrate
86−Rollback
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.
88+Row 2
89+Row 0
12290-}
12391
12492{-# LANGUAGE
12593 DataKinds
126− , DeriveGeneric
127− , FlexibleContexts
128− , FlexibleInstances
12994 , GADTs
13095 , LambdaCase
131− , OverloadedLabels
132− , OverloadedStrings
13396 , PolyKinds
134− , QuantifiedConstraints
135− , RankNTypes
97+ , OverloadedLabels
13698 , TypeApplications
99+ , FlexibleContexts
137100 , TypeOperators
138101#-}
139102
140103module Squeal.PostgreSQL.Migration
141104 ( -- * Migration
142105 Migration (..)
143− , Migratory (..)
144− , Terminally (..)
145− , terminally
146− , pureMigration
106+ , migrateUp
107+ , migrateDown
108+ -- * Aligned lists
109+ , AlignedList (..)
110+ , single
111+ -- * Migration table
147112 , MigrationsTable
148− , defaultMain
113+ , createMigrations
114+ , insertMigration
115+ , deleteMigration
116+ , selectMigration
149117 ) where
150118
151119import Control.Category
152120import Control.Monad
153−import Data.ByteString (ByteString)
154−import Data.Foldable (traverse_)
121+import Control.Monad.Base
122+import Control.Monad.Trans.Control
123+import Data.Monoid
124+import Generics.SOP (K(..))
155125import Data.Function ((&))
156−import Data.List ((\\))
157126import Data.Text (Text)
158−import Data.Time (UTCTime)
159−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
127+import Prelude hiding (id, (.))
166128
167−import Squeal.PostgreSQL.Alias
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
129+import Squeal.PostgreSQL
182130
183−-- | A `Migration` is a named "isomorphism" over a given category.
184−-- It should contain an inverse pair of `up` and `down`
185−-- instructions and a unique `name`.
186−data Migration p schemas0 schemas1 = Migration
131+-- | A `Migration` should contain an inverse pair of
132+-- `up` and `down` instructions and a unique `name`.
133+data Migration io schema0 schema1 = Migration
187134 { name :: Text -- ^ The `name` of a `Migration`.
188135 -- Each `name` in a `Migration` should be unique.
189− , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.
190− , down :: p schemas1 schemas0 -- ^ 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
136+ , up :: PQ schema0 schema1 io () -- ^ The `up` instruction of a `Migration`.
137+ , down :: PQ schema1 schema0 io () -- ^ The `down` instruction of a `Migration`.
260138 }
261139
262−instance Migratory (Terminally PQ IO) where
263−
264− migrateUp migration = unsafePQ . transactionally_ $ do
265− define createMigrations
266− upMigrations migration
267−
268− where
269−
270− upMigrations
271− :: Path (Migration (Terminally PQ IO)) schemas0 schemas1
272− -> PQ MigrationsSchemas MigrationsSchemas IO ()
273− upMigrations = \case
274− Done -> return ()
275− step :>> steps -> upMigration step >> upMigrations steps
276−
277− upMigration
278− :: Migration (Terminally PQ IO) schemas0 schemas1
279− -> PQ MigrationsSchemas MigrationsSchemas IO ()
280− upMigration step = do
281− executed <- queryExecuted step
282− unless (executed == 1) $ do
283− unsafePQ . runTerminally $ up step
284− manipulateParams_ insertMigration (Only (name step))
285−
286− queryExecuted
287− :: Migration (Terminally PQ IO) schemas0 schemas1
288− -> PQ MigrationsSchemas MigrationsSchemas IO Row
289− queryExecuted step = do
290− result <- runQueryParams selectMigration (Only (name step))
291− ntuples result
292−
293− migrateDown migrations = unsafePQ . transactionally_ $ do
294− define createMigrations
295− downMigrations migrations
296−
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))
140+-- | An `AlignedList` is a type-aligned list or free category.
141+data AlignedList p x0 x1 where
142+ Done :: AlignedList p x x
143+ (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2
144+infixr 7 :>>
145+instance Category (AlignedList p) where
146+ id = Done
147+ (.) list = \case
148+ Done -> list
149+ step :>> steps -> step :>> (steps >>> list)
150+
151+-- | A `single` step.
152+single :: p x0 x1 -> AlignedList p x0 x1
153+single step = step :>> Done
154+
155+-- | Run `Migration`s by creating the `MigrationsTable`
156+-- if it does not exist and then in a transaction, for each each `Migration`
157+-- query to see if the `Migration` is executed. If not, then
158+-- execute the `Migration` and insert its row in the `MigrationsTable`.
159+migrateUp
160+ :: MonadBaseControl IO io
161+ => AlignedList (Migration io) schema0 schema1 -- ^ migrations to run
162+ -> PQ
163+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)
164+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)
165+ io ()
166+migrateUp migration =
167+ define createMigrations
168+ & pqBind okResult
169+ & pqThen (transactionallySchema_ (upMigrations migration))
170+ where
314171
315− queryExecuted
316− :: Migration (Terminally PQ IO) schemas0 schemas1
317− -> PQ MigrationsSchemas MigrationsSchemas IO Row
318− queryExecuted step = do
319− result <- runQueryParams selectMigration (Only (name step))
320− ntuples result
172+ upMigrations
173+ :: MonadBaseControl IO io
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
206+ queryExecuted step = do
207+ result <- runQueryParams selectMigration (Only (name step))
208+ okResult 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
321227
322−unsafePQ :: (Functor m) => PQ db0 db1 m x -> PQ db0' db1' m x
323−unsafePQ (PQ pq) = PQ $ fmap (SOP.K . SOP.unK) . pq . SOP.K . SOP.unK
228+ downMigrations
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)
324274
325275-- | The `TableType` for a Squeal migration.
326276type MigrationsTable =
@@ -329,19 +279,10 @@ type MigrationsTable =
329279 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz
330280 ]
331281
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−
343282-- | 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
345286createMigrations =
346287 createTableIfNotExists #schema_migrations
347288 ( (text & notNullable) `as` #name :*
@@ -349,100 +290,27 @@ createMigrations =
349290 `as` #executed_at )
350291 ( unique #name `as` #migrations_unique_name )
351292
352−-- | Inserts a `Migration` into the `MigrationsTable`, returning
353−-- the time at which it was inserted.
354−insertMigration :: Manipulation_ MigrationsSchemas (Only Text) ()
355−insertMigration = insertInto_ #schema_migrations
356− (Values_ (Set (param @1) `as` #name :* Default `as` #executed_at))
357−
358−-- | Deletes a `Migration` from the `MigrationsTable`, returning
359−-- the time at which it was inserted.
360−deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()
293+-- | Inserts a `Migration` into the `MigrationsTable`
294+insertMigration
295+ :: Has "schema_migrations" schema ('Table MigrationsTable)
296+ => Manipulation schema '[ 'NotNull 'PGtext] '[]
297+insertMigration = insertRow_ #schema_migrations
298+ ( Set (param @1) `as` #name :*
299+ Default `as` #executed_at )
300+
301+-- | Deletes a `Migration` from the `MigrationsTable`
302+deleteMigration
303+ :: Has "schema_migrations" schema ('Table MigrationsTable)
304+ => Manipulation schema '[ 'NotNull 'PGtext ] '[]
361305deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)
362306
363307-- | Selects a `Migration` from the `MigrationsTable`, returning
364−-- the time at which it was inserted.
308+-- the time at which it was executed.
365309selectMigration
366− :: Query_ MigrationsSchemas (Only Text) (Only UTCTime)
367−selectMigration = select_ (#executed_at `as` #fromOnly)
368− $ from (table (#schema_migrations))
369− & 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
310+ :: Has "schema_migrations" schema ('Table MigrationsTable)
311+ => Query schema '[ 'NotNull 'PGtext ]
312+ '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]
313+selectMigration = select
314+ (#executed_at `as` #executed_at)
315+ ( from (table (#schema_migrations `as` #m))
316+ & where_ (#name .== param @1))
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
66Stability: experimental
77
88This 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
1010a `Definition` and `MonadPQ` for executing a `Manipulation` or `Query`,
1111and a `PQ` type with instances for them.
1212
1313Using 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
1515application's monad transformer stack, giving it an instance of `MonadPQ`.
1616
1717This module also provides functions for retrieving rows from the `LibPQ.Result`
@@ -24,7 +24,6 @@ of executing Squeal commands.
2424 , FunctionalDependencies
2525 , FlexibleContexts
2626 , FlexibleInstances
27− , InstanceSigs
2827 , OverloadedStrings
2928 , RankNTypes
3029 , ScopedTypeVariables
@@ -49,7 +48,9 @@ module Squeal.PostgreSQL.PQ
4948 , evalPQ
5049 , IndexedMonadTransPQ (..)
5150 , MonadPQ (..)
52− -- * Results
51+ , PQRun
52+ , pqliftWith
53+ -- * Result
5354 , LibPQ.Result
5455 , LibPQ.Row
5556 , ntuples
@@ -61,33 +62,22 @@ module Squeal.PostgreSQL.PQ
6162 , LibPQ.ExecStatus (..)
6263 , resultStatus
6364 , resultErrorMessage
64− , resultErrorCode
65− -- * Exceptions
66− , SquealException (..)
67− , PQState (..)
68− , okResult
69− , catchSqueal
70− , handleSqueal
71− , trySqueal
7265 ) where
7366
74−import Control.Exception (Exception, throw)
67+import Control.Exception.Lifted
68+import Control.Monad.Base
7569import Control.Monad.Except
7670import Control.Monad.Morph
77−import UnliftIO (MonadUnliftIO (..), bracket, catch, handle, try)
71+import Control.Monad.Trans.Control
7872import Data.ByteString (ByteString)
7973import Data.Foldable
8074import Data.Function ((&))
81−import Data.Functor ((<&>))
8275import Data.Kind
83−import Data.Text (pack, Text)
76+import Data.Monoid
8477import Data.Traversable
8578import Generics.SOP
86−import PostgreSQL.Binary.Encoding (encodingBytes)
8779
88−import qualified Control.Monad.Fail as Fail
8980import qualified Database.PostgreSQL.LibPQ as LibPQ
90−import qualified PostgreSQL.Binary.Encoding as Encoding
9181
9282import Squeal.PostgreSQL.Binary
9383import Squeal.PostgreSQL.Definition
@@ -100,6 +90,7 @@ import Control.Monad.Trans.Identity
10090import Control.Monad.Trans.Reader
10191import Control.Monad.Trans.Maybe
10292import Control.Monad.Trans.Cont
93+import Control.Monad.Trans.List
10394
10495import qualified Control.Monad.Trans.State.Lazy as Lazy
10596import qualified Control.Monad.Trans.State.Strict as Strict
@@ -108,9 +99,6 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict
10899import qualified Control.Monad.Trans.RWS.Lazy as Lazy
109100import qualified Control.Monad.Trans.RWS.Strict as Strict
110101
111−-- $setup
112−-- >>> import Squeal.PostgreSQL
113−
114102{- | Makes a new connection to the database server.
115103
116104This 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
137125with the wrong schema!
138126-}
139127connectdb
140− :: forall schemas io
141− . MonadIO io
128+ :: forall schema io
129+ . MonadBase IO io
142130 => ByteString -- ^ conninfo
143− -> io (K LibPQ.Connection schemas)
144−connectdb = fmap K . liftIO . LibPQ.connectdb
131+ -> io (K LibPQ.Connection schema)
132+connectdb = fmap K . liftBase . LibPQ.connectdb
145133
146134-- | Closes the connection to the server.
147−finish :: MonadIO io => K LibPQ.Connection schemas -> io ()
148−finish = liftIO . LibPQ.finish . unK
135+finish :: MonadBase IO io => K LibPQ.Connection schema -> io ()
136+finish = liftBase . LibPQ.finish . unK
149137
150138-- | Do `connectdb` and `finish` before and after a computation.
151139withConnection
152− :: forall schemas0 schemas1 io x
153− . MonadUnliftIO io
140+ :: forall schema0 schema1 io x
141+ . MonadBaseControl IO io
154142 => ByteString
155− -> PQ schemas0 schemas1 io x
143+ -> PQ schema0 schema1 io x
156144 -> io x
157145withConnection connString action = do
158146 K x <- bracket (connectdb connString) finish (unPQ action)
@@ -160,47 +148,47 @@ withConnection connString action = do
160148
161149-- | Safely `lowerConnection` to a smaller schema.
162150lowerConnection
163− :: K LibPQ.Connection (schema ': schemas)
164− -> K LibPQ.Connection schemas
151+ :: K LibPQ.Connection (table ': schema)
152+ -> K LibPQ.Connection schema
165153lowerConnection (K conn) = K conn
166154
167155-- | We keep track of the schema via an Atkey indexed state monad transformer,
168156-- `PQ`.
169157newtype PQ
170− (schemas0 :: SchemasType)
171− (schemas1 :: SchemasType)
158+ (schema0 :: SchemaType)
159+ (schema1 :: SchemaType)
172160 (m :: Type -> Type)
173161 (x :: Type) =
174− PQ { unPQ :: K LibPQ.Connection schemas0 -> m (K x schemas1) }
162+ PQ { unPQ :: K LibPQ.Connection schema0 -> m (K x schema1) }
175163
176−instance Monad m => Functor (PQ schemas0 schemas1 m) where
164+instance Monad m => Functor (PQ schema0 schema1 m) where
177165 fmap f (PQ pq) = PQ $ \ conn -> do
178166 K x <- pq conn
179167 return $ K (f x)
180168
181−-- | Run a `PQ` and keep the result and the `LibPQ.Connection`.
169+-- | Run a `PQ` and keep the result and the `Connection`.
182170runPQ
183171 :: Functor m
184− => PQ schemas0 schemas1 m x
185− -> K LibPQ.Connection schemas0
186− -> m (x, K LibPQ.Connection schemas1)
172+ => PQ schema0 schema1 m x
173+ -> K LibPQ.Connection schema0
174+ -> m (x, K LibPQ.Connection schema1)
187175runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn
188176 -- K x <- pq conn
189177 -- return (x, K (unK conn))
190178
191−-- | Execute a `PQ` and discard the result but keep the `LibPQ.Connection`.
179+-- | Execute a `PQ` and discard the result but keep the `Connection`.
192180execPQ
193181 :: Functor m
194− => PQ schemas0 schemas1 m x
195− -> K LibPQ.Connection schemas0
196− -> m (K LibPQ.Connection schemas1)
182+ => PQ schema0 schema1 m x
183+ -> K LibPQ.Connection schema0
184+ -> m (K LibPQ.Connection schema1)
197185execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn
198186
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.
200188evalPQ
201189 :: Functor m
202− => PQ schemas0 schemas1 m x
203− -> K LibPQ.Connection schemas0
190+ => PQ schema0 schema1 m x
191+ -> K LibPQ.Connection schema0
204192 -> m x
205193evalPQ (PQ pq) conn = unK <$> pq conn
206194
@@ -208,56 +196,60 @@ evalPQ (PQ pq) conn = unK <$> pq conn
208196-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).
209197-- An indexed monad transformer transforms a `Monad` into an indexed monad.
210198-- 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`.
212201class IndexedMonadTransPQ pq where
213202
214203 -- | indexed analog of `<*>`
215204 pqAp
216205 :: Monad m
217− => pq schemas0 schemas1 m (x -> y)
218− -> pq schemas1 schemas2 m x
219− -> pq schemas0 schemas2 m y
206+ => pq schema0 schema1 m (x -> y)
207+ -> pq schema1 schema2 m x
208+ -> pq schema0 schema2 m y
220209
221210 -- | indexed analog of `join`
222211 pqJoin
223212 :: Monad m
224− => pq schemas0 schemas1 m (pq schemas1 schemas2 m y)
225− -> pq schemas0 schemas2 m y
213+ => pq schema0 schema1 m (pq schema1 schema2 m y)
214+ -> pq schema0 schema2 m y
226215 pqJoin pq = pq & pqBind id
227216
228217 -- | indexed analog of `=<<`
229218 pqBind
230219 :: Monad m
231− => (x -> pq schemas1 schemas2 m y)
232− -> pq schemas0 schemas1 m x
233− -> pq schemas0 schemas2 m y
220+ => (x -> pq schema1 schema2 m y)
221+ -> pq schema0 schema1 m x
222+ -> pq schema0 schema2 m y
234223
235224 -- | indexed analog of flipped `>>`
236225 pqThen
237226 :: Monad m
238− => pq schemas1 schemas2 m y
239− -> pq schemas0 schemas1 m x
240− -> pq schemas0 schemas2 m y
227+ => pq schema1 schema2 m y
228+ -> pq schema0 schema1 m x
229+ -> pq schema0 schema2 m y
241230 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)
242231
243232 -- | indexed analog of `<=<`
244233 pqAndThen
245234 :: Monad m
246− => (y -> pq schemas1 schemas2 m z)
247− -> (x -> pq schemas0 schemas1 m y)
248− -> x -> pq schemas0 schemas2 m z
235+ => (y -> pq schema1 schema2 m z)
236+ -> (x -> pq schema0 schema1 m y)
237+ -> x -> pq schema0 schema2 m z
249238 pqAndThen g f x = pqBind g (f x)
250239
251− -- | Run a `Definition` with `LibPQ.exec`.
252− --
253− -- It should be functorial in effect.
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+
246+ -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law
254247 --
255− -- @define id = return ()@
256− -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@
248+ -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@
257249 define
258− :: MonadIO io
259− => Definition schemas0 schemas1
260− -> pq schemas0 schemas1 io ()
250+ :: MonadBase IO io
251+ => Definition schema0 schema1
252+ -> pq schema0 schema1 io (K LibPQ.Result '[])
261253
262254instance IndexedMonadTransPQ PQ where
263255
@@ -270,26 +262,26 @@ instance IndexedMonadTransPQ PQ where
270262 K x' <- x conn
271263 unPQ (f x') (K (unK conn))
272264
265+ pqEmbed (PQ pq) = PQ $ \ (K conn) -> do
266+ K x <- pq (K conn)
267+ return $ K x
268+
273269 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do
274− resultMaybe <- liftIO $ LibPQ.exec conn q
270+ resultMaybe <- liftBase $ LibPQ.exec conn q
275271 case resultMaybe of
276− Nothing -> throw $ ResultException
272+ Nothing -> error
277273 "define: LibPQ.exec returned no results"
278− Just result -> K <$> okResult_ result
274+ Just result -> return $ K (K result)
279275
280−{- | `MonadPQ` is an @mtl@ style constraint, similar to
281−`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to
276+{- | `MonadPQ` is an `mtl` style constraint, similar to
277+`Control.Monad.State.Class.MonadState`, for using `LibPQ` to
282278
283279* `manipulateParams` runs a `Manipulation` with params from a type
284280 with a `ToParams` constraint. It calls `LibPQ.execParams` and
285281 doesn't afraid of anything.
286282
287−* `manipulateParams_` is like `manipulateParams` for a returning-free statement.
288−
289283* `manipulate` is like `manipulateParams` for a parameter-free statement.
290284
291−* `manipulate_` is like `manipulate` for a returning-free statement.
292−
293285* `runQueryParams` is like `manipulateParams` for query statements.
294286
295287* `runQuery` is like `runQueryParams` for a parameter-free statement.
@@ -303,11 +295,11 @@ instance IndexedMonadTransPQ PQ where
303295* `forPrepared` is a flipped `traversePrepared`
304296
305297* `traversePrepared_` is like `traversePrepared` but works on `Foldable`
306− containers for a returning-free statement.
298+ containers and returns unit.
307299
308300* `forPrepared_` is a flipped `traversePrepared_`.
309301
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
311303 into your monad.
312304
313305To define an instance, you can minimally define only `manipulateParams`,
@@ -315,398 +307,305 @@ To define an instance, you can minimally define only `manipulateParams`,
315307a default instance.
316308
317309-}
318−class Monad pq => MonadPQ schemas pq | pq -> schemas where
310+class Monad pq => MonadPQ schema pq | pq -> schema where
319311 manipulateParams
320− :: (ToParams x params, All OidOfParam params)
321− => Manipulation '[] schemas params ys
322− -- ^ `insertInto`, `update` or `deleteFrom`
312+ :: ToParams x params
313+ => Manipulation schema params ys
314+ -- ^ `insertRows`, `update` or `deleteFrom`
323315 -> x -> pq (K LibPQ.Result ys)
324316 default manipulateParams
325− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
326− => (ToParams x params, All OidOfParam params)
327− => Manipulation '[] schemas params ys
328− -- ^ `insertInto`, `update` or `deleteFrom`
317+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
318+ => ToParams x params
319+ => Manipulation schema params ys
320+ -- ^ `insertRows`, `update` or `deleteFrom`
329321 -> x -> pq (K LibPQ.Result ys)
330322 manipulateParams manipulation params = lift $
331323 manipulateParams manipulation params
332324
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)
341326 manipulate statement = manipulateParams statement ()
342327
343− manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()
344− manipulate_ = void . manipulate
345−
346328 runQueryParams
347− :: (ToParams x params, All OidOfParam params)
348− => Query '[] '[] schemas params ys
329+ :: ToParams x params
330+ => Query schema params ys
349331 -- ^ `select` and friends
350332 -> x -> pq (K LibPQ.Result ys)
351333 runQueryParams = manipulateParams . queryStatement
352334
353335 runQuery
354− :: Query '[] '[] schemas '[] ys
336+ :: Query schema '[] ys
355337 -- ^ `select` and friends
356338 -> pq (K LibPQ.Result ys)
357339 runQuery q = runQueryParams q ()
358340
359341 traversePrepared
360− :: (ToParams x params, Traversable list, All OidOfParam params)
361− => Manipulation '[] schemas params ys
362− -- ^ `insertInto`, `update`, or `deleteFrom`, and friends
342+ :: (ToParams x params, Traversable list)
343+ => Manipulation schema params ys
344+ -- ^ `insertRows`, `update`, or `deleteFrom`, and friends
363345 -> list x -> pq (list (K LibPQ.Result ys))
364346 default traversePrepared
365− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
366− => (ToParams x params, Traversable list, All OidOfParam params)
367− => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))
347+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
348+ => (ToParams x params, Traversable list)
349+ => Manipulation schema params ys -> list x -> pq (list (K LibPQ.Result ys))
368350 traversePrepared manipulation params = lift $
369351 traversePrepared manipulation params
370352
371353 forPrepared
372− :: (ToParams x params, Traversable list, All OidOfParam params)
354+ :: (ToParams x params, Traversable list)
373355 => list x
374− -> Manipulation '[] schemas params ys
375− -- ^ `insertInto`, `update` or `deleteFrom`
356+ -> Manipulation schema params ys
357+ -- ^ `insertRows`, `update` or `deleteFrom`
376358 -> pq (list (K LibPQ.Result ys))
377359 forPrepared = flip traversePrepared
378360
379361 traversePrepared_
380− :: (ToParams x params, Foldable list, All OidOfParam params)
381− => Manipulation '[] schemas params '[]
382− -- ^ `insertInto`, `update` or `deleteFrom`
362+ :: (ToParams x params, Foldable list)
363+ => Manipulation schema params '[]
364+ -- ^ `insertRows`, `update` or `deleteFrom`
383365 -> list x -> pq ()
384366 default traversePrepared_
385− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
386− => (ToParams x params, Foldable list, All OidOfParam params)
387− => Manipulation '[] schemas params '[]
388− -- ^ `insertInto`, `update` or `deleteFrom`
367+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
368+ => (ToParams x params, Foldable list)
369+ => Manipulation schema params '[]
370+ -- ^ `insertRows`, `update` or `deleteFrom`
389371 -> list x -> pq ()
390372 traversePrepared_ manipulation params = lift $
391373 traversePrepared_ manipulation params
392374
393375 forPrepared_
394− :: (ToParams x params, Foldable list, All OidOfParam params)
376+ :: (ToParams x params, Foldable list)
395377 => list x
396− -> Manipulation '[] schemas params '[]
397− -- ^ `insertInto`, `update` or `deleteFrom`
378+ -> Manipulation schema params '[]
379+ -- ^ `insertRows`, `update` or `deleteFrom`
398380 -> pq ()
399381 forPrepared_ = flip traversePrepared_
400382
401383 liftPQ :: (LibPQ.Connection -> IO a) -> pq a
402384 default liftPQ
403− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
385+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)
404386 => (LibPQ.Connection -> IO a) -> pq a
405387 liftPQ = lift . liftPQ
406388
407−instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)
408− => MonadPQ schemas (PQ schemas0 schemas1 io) where
389+instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)
390+ => MonadPQ schema (PQ schema0 schema1 io) where
409391
410392 manipulateParams
411− (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =
393+ (UnsafeManipulation q :: Manipulation schema ps ys) (params :: x) =
412394 PQ $ \ (K conn) -> do
413395 let
414− paramSet
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
396+ toParam' bytes = (LibPQ.invalidOid,bytes,LibPQ.Binary)
397+ params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))
425398 q' = q <> ";"
426− resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary
399+ resultMaybe <- liftBase $ LibPQ.execParams conn q' params' LibPQ.Binary
427400 case resultMaybe of
428− Nothing -> throw $ ResultException
401+ Nothing -> error
429402 "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)
433404
434405 traversePrepared
435− (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =
436− PQ $ \ (K conn) -> liftIO $ do
437− let
438− 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')
406+ (UnsafeManipulation q :: Manipulation schema xs ys) (list :: list x) =
407+ PQ $ \ (K conn) -> liftBase $ do
408+ let temp = "temporary_statement"
409+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing
446410 case prepResultMaybe of
447− Nothing -> throw $ ResultException
411+ Nothing -> error
448412 "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
450417 results <- for list $ \ params -> do
451418 let
452− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
419+ toParam' bytes = (bytes,LibPQ.Binary)
453420 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
454421 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
455422 case resultMaybe of
456− Nothing -> throw $ ResultException
423+ Nothing -> error
457424 "traversePrepared: LibPQ.execParams returned no results"
458− Just result -> do
459− okResult_ result
460− return $ K result
425+ Just result -> return $ K result
461426 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
462427 case deallocResultMaybe of
463− Nothing -> throw $ ResultException
428+ Nothing -> error
464429 "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
466434 return (K results)
467435
468436 traversePrepared_
469− (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =
470− PQ $ \ (K conn) -> liftIO $ do
471− let
472− 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')
437+ (UnsafeManipulation q :: Manipulation schema xs '[]) (list :: list x) =
438+ PQ $ \ (K conn) -> liftBase $ do
439+ let temp = "temporary_statement"
440+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing
480441 case prepResultMaybe of
481− Nothing -> throw $ ResultException
442+ Nothing -> error
482443 "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
484448 for_ list $ \ params -> do
485449 let
486− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
450+ toParam' bytes = (bytes,LibPQ.Binary)
487451 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
488452 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
489453 case resultMaybe of
490− Nothing -> throw $ ResultException
454+ Nothing -> error
491455 "traversePrepared_: LibPQ.execParams returned no results"
492− Just result -> okResult_ result
456+ Just _result -> return ()
493457 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
494458 case deallocResultMaybe of
495− Nothing -> throw $ ResultException
459+ Nothing -> error
496460 "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
498465 return (K ())
499466
500467 liftPQ pq = PQ $ \ (K conn) -> do
501− y <- liftIO $ pq conn
468+ y <- liftBase $ pq conn
502469 return (K y)
503470
504−instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)
505−instance MonadPQ schemas m => MonadPQ schemas (ReaderT r m)
506−instance MonadPQ schemas m => MonadPQ schemas (Strict.StateT s m)
507−instance MonadPQ schemas m => MonadPQ schemas (Lazy.StateT s m)
508−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.WriterT w m)
509−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.WriterT w m)
510−instance MonadPQ schemas m => MonadPQ schemas (MaybeT m)
511−instance MonadPQ schemas m => MonadPQ schemas (ExceptT e m)
512−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.RWST r w s m)
513−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.RWST r w s m)
514−instance MonadPQ schemas m => MonadPQ schemas (ContT r m)
515−
516−instance (Monad m, schemas0 ~ schemas1)
517− => Applicative (PQ schemas0 schemas1 m) where
471+instance MonadPQ schema m => MonadPQ schema (IdentityT m)
472+instance MonadPQ schema m => MonadPQ schema (ReaderT r m)
473+instance MonadPQ schema m => MonadPQ schema (Strict.StateT s m)
474+instance MonadPQ schema m => MonadPQ schema (Lazy.StateT s m)
475+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.WriterT w m)
476+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.WriterT w m)
477+instance MonadPQ schema m => MonadPQ schema (MaybeT m)
478+instance MonadPQ schema m => MonadPQ schema (ExceptT e m)
479+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.RWST r w s m)
480+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.RWST r w s m)
481+instance MonadPQ schema m => MonadPQ schema (ContT r m)
482+instance MonadPQ schema m => MonadPQ schema (ListT m)
483+
484+instance (Monad m, schema0 ~ schema1)
485+ => Applicative (PQ schema0 schema1 m) where
518486 pure x = PQ $ \ _conn -> pure (K x)
519487 (<*>) = pqAp
520488
521−instance (Monad m, schemas0 ~ schemas1)
522− => Monad (PQ schemas0 schemas1 m) where
489+instance (Monad m, schema0 ~ schema1)
490+ => Monad (PQ schema0 schema1 m) where
523491 return = pure
524492 (>>=) = flip pqBind
525493
526−instance (Monad m, schemas0 ~ schemas1)
527− => Fail.MonadFail (PQ schemas0 schemas1 m) where
528− fail = Fail.fail
529−
530−instance schemas0 ~ schemas1 => MFunctor (PQ schemas0 schemas1) where
494+instance schema0 ~ schema1 => MFunctor (PQ schema0 schema1) where
531495 hoist f (PQ pq) = PQ (f . pq)
532496
533−instance schemas0 ~ schemas1 => MonadTrans (PQ schemas0 schemas1) where
497+instance schema0 ~ schema1 => MonadTrans (PQ schema0 schema1) where
534498 lift m = PQ $ \ _conn -> do
535499 x <- m
536500 return (K x)
537501
538−instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where
502+instance schema0 ~ schema1 => MMonad (PQ schema0 schema1) where
539503 embed f (PQ pq) = PQ $ \ conn -> do
540504 evalPQ (f (pq conn)) conn
541505
542−instance (MonadIO m, schema0 ~ schema1)
543− => MonadIO (PQ schema0 schema1 m) where
544− liftIO = lift . liftIO
506+instance (MonadBase b m, schema0 ~ schema1)
507+ => MonadBase b (PQ schema0 schema1 m) where
508+ liftBase = lift . liftBase
545509
546−instance (MonadUnliftIO m, schemas0 ~ schemas1)
547− => MonadUnliftIO (PQ schemas0 schemas1 m) where
548− withRunInIO
549− :: ((forall a . PQ schemas0 schema1 m a -> IO a) -> IO b)
550− -> PQ schemas0 schema1 m b
551− withRunInIO inner = PQ $ \conn ->
552− withRunInIO $ \(run :: (forall x . m x -> IO x)) ->
553− K <$> inner (\pq -> run $ unK <$> unPQ pq conn)
510+-- | A snapshot of the state of a `PQ` computation.
511+type PQRun schema =
512+ forall m x. Monad m => PQ schema schema m x -> m (K x schema)
513+
514+-- | Helper function in defining `MonadBaseControl` instance for `PQ`.
515+pqliftWith :: Functor m => (PQRun schema -> m a) -> PQ schema schema m a
516+pqliftWith f = 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
554525
555526-- | Get a row corresponding to a given row number from a `LibPQ.Result`,
556527-- throwing an exception if the row number is out of bounds.
557528getRow
558− :: (FromRow columns y, MonadIO io)
529+ :: (FromRow columns y, MonadBase IO io)
559530 => LibPQ.Row
560531 -- ^ row number
561532 -> K LibPQ.Result columns
562533 -- ^ result
563534 -> io y
564−getRow r (K result :: K LibPQ.Result columns) = liftIO $ do
535+getRow r (K result :: K LibPQ.Result columns) = liftBase $ do
565536 numRows <- LibPQ.ntuples result
566− when (numRows < r) $ throw $ ResultException $
567− "getRow: expected at least " <> pack (show r) <> "rows but only saw "
568− <> pack (show numRows)
537+ when (numRows < r) $ error $
538+ "getRow: expected at least " <> show r <> "rows but only saw "
539+ <> show numRows
569540 let len = fromIntegral (lengthSList (Proxy @columns))
570541 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
571542 case fromList row' of
572− Nothing -> throw $ ResultException "getRow: found unexpected length"
573− Just row -> case fromRow @columns row of
574− Left parseError -> throw $ ParseException $ "getRow: " <> parseError
575− Right y -> return y
543+ Nothing -> error "getRow: found unexpected length"
544+ Just row -> return $ fromRow @columns row
576545
577546-- | Intended to be used for unfolding in streaming libraries, `nextRow`
578547-- takes a total number of rows (which can be found with `ntuples`)
579548-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,
580549-- otherwise returning the row along with the next row number.
581550nextRow
582− :: (FromRow columns y, MonadIO io)
551+ :: (FromRow columns y, MonadBase IO io)
583552 => LibPQ.Row -- ^ total number of rows
584553 -> K LibPQ.Result columns -- ^ result
585554 -> LibPQ.Row -- ^ row number
586555 -> io (Maybe (LibPQ.Row,y))
587556nextRow 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
589558 let len = fromIntegral (lengthSList (Proxy @columns))
590559 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
591560 case fromList row' of
592− Nothing -> throw $ ResultException "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)
561+ Nothing -> error "nextRow: found unexpected length"
562+ Just row -> return $ Just (r+1, fromRow @columns row)
596563
597564-- | Get all rows from a `LibPQ.Result`.
598565getRows
599− :: (FromRow columns y, MonadIO io)
566+ :: (FromRow columns y, MonadBase IO io)
600567 => K LibPQ.Result columns -- ^ result
601568 -> io [y]
602−getRows (K result :: K LibPQ.Result columns) = liftIO $ do
569+getRows (K result :: K LibPQ.Result columns) = liftBase $ do
603570 let len = fromIntegral (lengthSList (Proxy @columns))
604571 numRows <- LibPQ.ntuples result
605572 for [0 .. numRows - 1] $ \ r -> do
606573 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
607574 case fromList row' of
608− Nothing -> throw $ ResultException "getRows: found unexpected length"
609− Just row -> case fromRow @columns row of
610− Left parseError -> throw $ ParseException $ "getRows: " <> parseError
611− Right y -> return y
575+ Nothing -> error "getRows: found unexpected length"
576+ Just row -> return $ fromRow @columns row
612577
613578-- | Get the first row if possible from a `LibPQ.Result`.
614579firstRow
615− :: (FromRow columns y, MonadIO io)
580+ :: (FromRow columns y, MonadBase IO io)
616581 => K LibPQ.Result columns -- ^ result
617582 -> io (Maybe y)
618−firstRow (K result :: K LibPQ.Result columns) = liftIO $ do
583+firstRow (K result :: K LibPQ.Result columns) = liftBase $ do
619584 numRows <- LibPQ.ntuples result
620585 if numRows <= 0 then return Nothing else do
621586 let len = fromIntegral (lengthSList (Proxy @columns))
622587 row' <- traverse (LibPQ.getvalue result 0) [0 .. len - 1]
623588 case fromList row' of
624− Nothing -> throw $ ResultException "firstRow: found unexpected length"
625− Just row -> case fromRow @columns row of
626− Left parseError -> throw $ ParseException $ "firstRow: " <> parseError
627− Right y -> return $ Just y
589+ Nothing -> error "firstRow: found unexpected length"
590+ Just row -> return . Just $ fromRow @columns row
628591
629592-- | Lifts actions on results from @LibPQ@.
630593liftResult
631− :: MonadIO io
594+ :: MonadBase IO io
632595 => (LibPQ.Result -> IO x)
633596 -> K LibPQ.Result results -> io x
634−liftResult f (K result) = liftIO $ f result
597+liftResult f (K result) = liftBase $ f result
635598
636599-- | 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
638601ntuples = liftResult LibPQ.ntuples
639602
640603-- | 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
642605resultStatus = liftResult LibPQ.resultStatus
643606
644607-- | Returns the error message most recently generated by an operation
645608-- on the connection.
646609resultErrorMessage
647− :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)
610+ :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)
648611resultErrorMessage = 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+104−73
@@ -1,40 +1,17 @@
11{-|
2−Module: Squeal.PostgreSQL.Pool
3−Description: Connection pools
2+Module: Squeal.PostgreSQL.Definition
3+Description: Pooled connections
44Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
8−Connection pools.
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
8+A `MonadPQ` for pooled connections.
319-}
3210
3311{-# LANGUAGE
3412 DeriveFunctor
3513 , FlexibleContexts
3614 , FlexibleInstances
37− , InstanceSigs
3815 , MultiParamTypeClasses
3916 , RankNTypes
4017 , ScopedTypeVariables
@@ -45,24 +22,55 @@ a
4522
4623module Squeal.PostgreSQL.Pool
4724 ( -- * Pools
48− Pool
25+ PoolPQ (..)
4926 , createConnectionPool
50− , usingConnectionPool
51− , destroyConnectionPool
27+ , Pool
28+ , destroyAllResources
29+ , PoolPQRun
30+ , poolpqliftWith
5231 ) where
5332
33+import Control.Monad.Base
34+import Control.Monad.Trans
35+import Control.Monad.Trans.Control
5436import Data.ByteString
37+import Data.Pool
5538import Data.Time
56−import Generics.SOP (K(..), unK)
57−import UnliftIO (MonadUnliftIO (..))
58−import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)
39+import Generics.SOP (K(..))
5940
6041import Squeal.PostgreSQL.PQ
42+import Squeal.PostgreSQL.Schema
43+
44+{- | `PoolPQ` @schema@ should be a drop-in replacement for `PQ` @schema schema@.
45+
46+Typical use case would be to create your pool using `createConnectionPool` and run anything that requires the pool connection with it.
47+
48+Here's a simplified example:
49+
50+> type Schema = '[ "tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint2])]
51+>
52+> someQuery :: Manipulation Schema '[ 'NotNull 'PGint2] '[]
53+> someQuery = insertRow #tab
54+> (Set (param @1) `As` #col :* Nil)
55+> OnConflictDoNothing (Returning Nil)
56+>
57+> insertOne :: (MonadBaseControl IO m, MonadPQ Schema m) => m ()
58+> insertOne = void $ manipulateParams someQuery . Only $ (1 :: Int16)
59+>
60+> insertOneInPool :: ByteString -> IO ()
61+> insertOneInPool connectionString = do
62+> pool <- createConnectionPool connectionString 1 0.5 10
63+> liftIO $ runPoolPQ (insertOne) pool
64+
65+-}
66+newtype PoolPQ (schema :: SchemaType) m x =
67+ PoolPQ { runPoolPQ :: Pool (K Connection schema) -> m x }
68+ deriving Functor
6169
6270-- | Create a striped pool of connections.
6371-- 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.
6472createConnectionPool
65− :: MonadUnliftIO io
73+ :: MonadBase IO io
6674 => ByteString
6775 -- ^ The passed string can be empty to use all default parameters, or it can
6876 -- contain one or more parameter settings separated by whitespace.
@@ -78,45 +86,68 @@ createConnectionPool
7886 -> Int
7987 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.
8088 -- 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))
82−createConnectionPool conninfo stripes idle maxResrc =
89+ -> io (Pool (K Connection schema))
90+createConnectionPool conninfo stripes idle maxResrc = liftBase $
8391 createPool (connectdb conninfo) finish stripes idle maxResrc
8492
85−{-|
86−Temporarily take a connection from a `Pool`, perform an action with it,
87−and return it to the pool afterwards.
88−
89−If the pool has an idle connection available, it is used immediately.
90−Otherwise, if the maximum number of connections has not yet been reached,
91−a new connection is created and used.
92−If the maximum number of connections has been reached, this function blocks
93−until a connection becomes available.
94−-}
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−
102−{- |
103−Destroy all connections in all stripes in the pool.
104−Note that this will ignore any exceptions in the destroy function.
105−
106−This function is useful when you detect that all connections
107−in the pool are broken. For example after a database has been
108−restarted all connections opened before the restart will be broken.
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−
113−Another use-case for this function is that when you know you are done
114−with the pool you can destroy all idle connections immediately
115−instead of waiting on the garbage collector to destroy them,
116−thus freeing up those connections sooner.
117−-}
118−destroyConnectionPool
119− :: MonadUnliftIO io
120− => Pool (K Connection schemas) -- ^ pool
121− -> io ()
122−destroyConnectionPool = destroyAllResources
93+-- | `Applicative` instance for `PoolPQ`.
94+instance Monad m => Applicative (PoolPQ schema m) where
95+ pure x = PoolPQ $ \ _ -> pure x
96+ PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do
97+ f' <- f pool
98+ x' <- x pool
99+ return $ f' x'
100+
101+-- | `Monad` instance for `PoolPQ`.
102+instance Monad m => Monad (PoolPQ schema m) where
103+ return = pure
104+ PoolPQ x >>= f = PoolPQ $ \ pool -> do
105+ x' <- x pool
106+ runPoolPQ (f x') pool
107+
108+-- | `MonadTrans` instance for `PoolPQ`.
109+instance MonadTrans (PoolPQ schema) where
110+ lift m = PoolPQ $ \ _pool -> m
111+
112+-- | `MonadBase` instance for `PoolPQ`.
113+instance MonadBase b m => MonadBase b (PoolPQ schema m) where
114+ liftBase = lift . liftBase
115+
116+-- | `MonadPQ` instance for `PoolPQ`.
117+instance MonadBaseControl IO io => MonadPQ schema (PoolPQ schema io) where
118+ manipulateParams manipulation params = PoolPQ $ \ pool -> do
119+ withResource pool $ \ conn -> do
120+ (K result :: K (K Result ys) schema) <- flip unPQ conn $
121+ manipulateParams manipulation params
122+ return result
123+ traversePrepared manipulation params = PoolPQ $ \ pool ->
124+ withResource pool $ \ conn -> do
125+ (K result :: K (list (K Result ys)) schema) <- flip unPQ conn $
126+ traversePrepared manipulation params
127+ return result
128+ traversePrepared_ manipulation params = PoolPQ $ \ pool -> do
129+ withResource pool $ \ conn -> do
130+ (_ :: K () schema) <- flip unPQ conn $
131+ traversePrepared_ manipulation params
132+ return ()
133+ liftPQ m = PoolPQ $ \ pool ->
134+ withResource pool $ \ conn -> do
135+ (K result :: K result schema) <- flip unPQ conn $
136+ liftPQ m
137+ return result
138+
139+-- | A snapshot of the state of a `PoolPQ` computation.
140+type PoolPQRun schema =
141+ forall m x. Monad m => PoolPQ schema m x -> m x
142+
143+-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.
144+poolpqliftWith :: Functor m => (PoolPQRun schema -> m a) -> PoolPQ schema m a
145+poolpqliftWith f = PoolPQ $ \ pool ->
146+ (f $ \ pq -> runPoolPQ pq pool)
147+
148+-- | `MonadBaseControl` instance for `PoolPQ`.
149+instance MonadBaseControl b m => MonadBaseControl b (PoolPQ schema m) where
150+ type StM (PoolPQ schema m) x = StM m x
151+ liftBaseWith f =
152+ poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run
153+ restoreM = PoolPQ . const . restoreM
squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+624−648
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL.Query
33Description: Squeal queries
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -17,12 +17,8 @@ Squeal queries.
1717 , GeneralizedNewtypeDeriving
1818 , LambdaCase
1919 , MultiParamTypeClasses
20− , OverloadedLabels
2120 , OverloadedStrings
22− , QuantifiedConstraints
23− , ScopedTypeVariables
2421 , StandaloneDeriving
25− , TypeApplications
2622 , TypeFamilies
2723 , TypeInType
2824 , TypeOperators
@@ -32,58 +28,72 @@ Squeal queries.
3228
3329module Squeal.PostgreSQL.Query
3430 ( -- * Queries
35− Query_
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
31+ Query (UnsafeQuery, renderQuery)
4932 , union
5033 , unionAll
5134 , intersect
5235 , intersectAll
5336 , except
5437 , exceptAll
55− -- ** With
56− , With (..)
57− , CommonTableExpression (..)
58− , withRecursive
38+ -- * Select
39+ , select
40+ , selectDistinct
41+ , selectStar
42+ , selectDistinctStar
43+ , selectDotStar
44+ , selectDistinctDotStar
45+ , values
46+ , values_
5947 -- * Table Expressions
6048 , TableExpression (..)
49+ , renderTableExpression
6150 , from
6251 , where_
6352 , groupBy
6453 , having
54+ , orderBy
6555 , limit
6656 , offset
67− -- * From Clauses
57+ -- ** JSON table expressions
58+ , PGjson_each
59+ , PGjsonb_each
60+ , jsonEach
61+ , jsonbEach
62+ , jsonEachAsText
63+ , jsonbEachAsText
64+ , jsonPopulateRecordAs
65+ , jsonbPopulateRecordAs
66+ , jsonPopulateRecordSetAs
67+ , jsonbPopulateRecordSetAs
68+ , jsonToRecordAs
69+ , jsonbToRecordAs
70+ , jsonToRecordSetAs
71+ , jsonbToRecordSetAs
72+ -- * From
6873 , FromClause (..)
6974 , table
7075 , subquery
7176 , view
72− , common
7377 , crossJoin
7478 , innerJoin
7579 , leftOuterJoin
7680 , rightOuterJoin
7781 , fullOuterJoin
7882 -- * Grouping
79− , By (..)
80− , GroupByClause (..)
81− , HavingClause (..)
83+ , By (By1, By2)
84+ , renderBy
85+ , GroupByClause (NoGroups, Group)
86+ , renderGroupByClause
87+ , HavingClause (NoHaving, Having)
88+ , renderHavingClause
89+ -- * Sorting
90+ , SortExpression (..)
91+ , renderSortExpression
8292 ) where
8393
8494import Control.DeepSeq
8595import Data.ByteString (ByteString)
86−import Data.Kind (Type)
96+import Data.Monoid hiding (All)
8797import Data.String
8898import Data.Word
8999import Generics.SOP hiding (from)
@@ -91,76 +101,25 @@ import GHC.TypeLits
91101
92102import qualified GHC.Generics as GHC
93103
94−import Squeal.PostgreSQL.Alias
95104import 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
101105import Squeal.PostgreSQL.Render
102106import Squeal.PostgreSQL.Schema
103107
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−{- |
112−The process of retrieving or the command to retrieve data from
113−a database is called a `Query`.
114−
115−The general `Query` type is parameterized by
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−
133108{- |
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−:}
109+The process of retrieving or the command to retrieve data from a database
110+is called a `Query`. The `select`, `selectStar`, `selectDotStar`,
111+`selectDistinct`, `selectDistinctStar` and `selectDistinctDotStar` commands
112+are used to specify queries.
155113
156114simple query:
157115
158−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]
159−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
160116>>> :{
161117let
162− query :: Query_ (Public Schema) () (Row Int32 Int32)
163− query = select Star (from (table #tab))
118+ query :: Query
119+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
120+ '[]
121+ '["col" ::: 'Null 'PGint4]
122+ query = selectStar (from (table #tab))
164123in printSQL query
165124:}
166125SELECT * FROM "tab" AS "tab"
@@ -169,22 +128,34 @@ restricted query:
169128
170129>>> :{
171130let
172− query :: Query_ (Public Schema) () (Row Int32 Int32)
131+ query :: Query
132+ '[ "tab" ::: 'Table ('[] :=>
133+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
134+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
135+ '[]
136+ '[ "sum" ::: 'NotNull 'PGint4
137+ , "col1" ::: 'NotNull 'PGint4 ]
173138 query =
174− select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)
139+ select
140+ ((#col1 + #col2) `as` #sum :* #col1)
175141 ( from (table #tab)
176142 & where_ (#col1 .> #col2)
177143 & where_ (#col2 .> 0) )
178144in printSQL query
179145:}
180−SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
146+SELECT ("col1" + "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
181147
182148subquery:
183149
184150>>> :{
185151let
186− query :: Query_ (Public Schema) () (Row Int32 Int32)
187− query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))
152+ query :: Query
153+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
154+ '[]
155+ '["col" ::: 'Null 'PGint4]
156+ query =
157+ selectStar
158+ (from (subquery (selectStar (from (table #tab)) `as` #sub)))
188159in printSQL query
189160:}
190161SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"
@@ -193,8 +164,12 @@ limits and offsets:
193164
194165>>> :{
195166let
196− query :: Query_ (Public Schema) () (Row Int32 Int32)
197− query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)
167+ query :: Query
168+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
169+ '[]
170+ '["col" ::: 'Null 'PGint4]
171+ query = selectStar
172+ (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)
198173in printSQL query
199174:}
200175SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4
@@ -203,80 +178,85 @@ parameterized query:
203178
204179>>> :{
205180let
206− query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)
207− query = select Star (from (table #tab) & where_ (#col1 .> param @1))
181+ query :: Query
182+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGfloat8])]
183+ '[ 'NotNull 'PGfloat8]
184+ '["col" ::: 'NotNull 'PGfloat8]
185+ query = selectStar
186+ (from (table #tab) & where_ (#col .> param @1))
208187in printSQL query
209188:}
210−SELECT * FROM "tab" AS "tab" WHERE ("col1" > ($1 :: int4))
189+SELECT * FROM "tab" AS "tab" WHERE ("col" > ($1 :: float8))
211190
212191aggregation query:
213192
214193>>> :{
215194let
216− query :: Query_ (Public Schema) () (Row Int64 Int32)
195+ query :: Query
196+ '[ "tab" ::: 'Table ('[] :=>
197+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4
198+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]
199+ '[]
200+ '[ "sum" ::: 'NotNull 'PGint4
201+ , "col1" ::: 'NotNull 'PGint4 ]
217202 query =
218− select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)
203+ select (sum_ #col2 `as` #sum :* #col1)
219204 ( from (table (#tab `as` #table1))
220205 & groupBy #col1
221− & having (sum_ (Distinct #col2) .> 1) )
206+ & having (#col1 + sum_ #col2 .> 1) )
222207in printSQL query
223208:}
224−SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (sum(DISTINCT "col2") > 1)
209+SELECT sum("col2") AS "sum", "col1" AS "col1" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + sum("col2")) > 1)
225210
226211sorted query:
227212
228213>>> :{
229214let
230− query :: Query_ (Public Schema) () (Row Int32 Int32)
231− query = select Star (from (table #tab) & orderBy [#col1 & Asc])
215+ query :: Query
216+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
217+ '[]
218+ '["col" ::: 'Null 'PGint4]
219+ query = selectStar
220+ (from (table #tab) & orderBy [#col & AscNullsFirst])
232221in printSQL query
233222:}
234−SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC
223+SELECT * FROM "tab" AS "tab" ORDER BY "col" ASC NULLS FIRST
235224
236225joins:
237226
238−>>> :{
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−
227+>>> :set -XFlexibleContexts
273228>>> :{
274229let
275− query :: Query_ (Public OrdersSchema) () Order
276− query = select_
277− ( #o ! #price `as` #price :*
278− #c ! #name `as` #customerName :*
279− #s ! #name `as` #shipperName )
230+ query :: Query
231+ '[ "orders" ::: 'Table (
232+ '["pk_orders" ::: PrimaryKey '["id"]
233+ ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]
234+ ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"]] :=>
235+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
236+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4
237+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4
238+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4
239+ ])
240+ , "customers" ::: 'Table (
241+ '["pk_customers" ::: PrimaryKey '["id"]] :=>
242+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
243+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
244+ ])
245+ , "shippers" ::: 'Table (
246+ '["pk_shippers" ::: PrimaryKey '["id"]] :=>
247+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
248+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
249+ ])
250+ ]
251+ '[]
252+ '[ "order_price" ::: 'NotNull 'PGfloat4
253+ , "customer_name" ::: 'NotNull 'PGtext
254+ , "shipper_name" ::: 'NotNull 'PGtext
255+ ]
256+ query = select
257+ ( #o ! #price `as` #order_price :*
258+ #c ! #name `as` #customer_name :*
259+ #s ! #name `as` #shipper_name )
280260 ( from (table (#orders `as` #o)
281261 & innerJoin (table (#customers `as` #c))
282262 (#o ! #customer_id .== #c ! #id)
@@ -284,345 +264,190 @@ let
284264 (#o ! #shipper_id .== #s ! #id)) )
285265in printSQL query
286266:}
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")
267+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")
288268
289269self-join:
290270
291271>>> :{
292272let
293− query :: Query_ (Public Schema) () (Row Int32 Int32)
294− query = select
295− (#t1 & DotStar)
273+ query :: Query
274+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
275+ '[]
276+ '["col" ::: 'Null 'PGint4]
277+ query = selectDotStar #t1
296278 (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))
297279in printSQL query
298280:}
299281SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"
300282
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−
313283set operations:
314284
315285>>> :{
316286let
317− query :: Query_ (Public Schema) () (Row Int32 Int32)
318− query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))
319−in printSQL query
320−:}
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)
287+ query :: Query
288+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]
289+ '[]
290+ '["col" ::: 'Null 'PGint4]
353291 query =
354− select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))
355− & where_ (exists (
356− select Star (from (table (#tab `as` #t2))
357− & where_ (#t2 ! #col2 .== #t1 ! #col1)))))
292+ selectStar (from (table #tab))
293+ `unionAll`
294+ selectStar (from (table #tab))
358295in printSQL query
359296:}
360−SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))
361−
297+(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")
362298-}
363−type family Query_
364− (schemas :: SchemasType)
365− (parameters :: Type)
366− (row :: Type) where
367− Query_ schemas params row =
368− Query '[] '[] schemas (TuplePG params) (RowPG row)
299+newtype Query
300+ (schema :: SchemaType)
301+ (params :: [NullityType])
302+ (columns :: RelationType)
303+ = UnsafeQuery { renderQuery :: ByteString }
304+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
305+instance RenderSQL (Query schema params columns) where renderSQL = renderQuery
369306
370307-- | The results of two queries can be combined using the set operation
371308-- `union`. Duplicate rows are eliminated.
372309union
373− :: Query outer commons schemas params columns
374− -> Query outer commons schemas params columns
375− -> Query outer commons schemas params columns
310+ :: Query schema params columns
311+ -> Query schema params columns
312+ -> Query schema params columns
376313q1 `union` q2 = UnsafeQuery $
377− parenthesized (renderSQL q1)
314+ parenthesized (renderQuery q1)
378315 <+> "UNION"
379− <+> parenthesized (renderSQL q2)
316+ <+> parenthesized (renderQuery q2)
380317
381318-- | The results of two queries can be combined using the set operation
382319-- `unionAll`, the disjoint union. Duplicate rows are retained.
383320unionAll
384− :: Query outer commons schemas params columns
385− -> Query outer commons schemas params columns
386− -> Query outer commons schemas params columns
321+ :: Query schema params columns
322+ -> Query schema params columns
323+ -> Query schema params columns
387324q1 `unionAll` q2 = UnsafeQuery $
388− parenthesized (renderSQL q1)
325+ parenthesized (renderQuery q1)
389326 <+> "UNION" <+> "ALL"
390− <+> parenthesized (renderSQL q2)
327+ <+> parenthesized (renderQuery q2)
391328
392329-- | The results of two queries can be combined using the set operation
393330-- `intersect`, the intersection. Duplicate rows are eliminated.
394331intersect
395− :: Query outer commons schemas params columns
396− -> Query outer commons schemas params columns
397− -> Query outer commons schemas params columns
332+ :: Query schema params columns
333+ -> Query schema params columns
334+ -> Query schema params columns
398335q1 `intersect` q2 = UnsafeQuery $
399− parenthesized (renderSQL q1)
336+ parenthesized (renderQuery q1)
400337 <+> "INTERSECT"
401− <+> parenthesized (renderSQL q2)
338+ <+> parenthesized (renderQuery q2)
402339
403340-- | The results of two queries can be combined using the set operation
404341-- `intersectAll`, the intersection. Duplicate rows are retained.
405342intersectAll
406− :: Query outer commons schemas params columns
407− -> Query outer commons schemas params columns
408− -> Query outer commons schemas params columns
343+ :: Query schema params columns
344+ -> Query schema params columns
345+ -> Query schema params columns
409346q1 `intersectAll` q2 = UnsafeQuery $
410− parenthesized (renderSQL q1)
347+ parenthesized (renderQuery q1)
411348 <+> "INTERSECT" <+> "ALL"
412− <+> parenthesized (renderSQL q2)
349+ <+> parenthesized (renderQuery q2)
413350
414351-- | The results of two queries can be combined using the set operation
415352-- `except`, the set difference. Duplicate rows are eliminated.
416353except
417− :: Query outer commons schemas params columns
418− -> Query outer commons schemas params columns
419− -> Query outer commons schemas params columns
354+ :: Query schema params columns
355+ -> Query schema params columns
356+ -> Query schema params columns
420357q1 `except` q2 = UnsafeQuery $
421− parenthesized (renderSQL q1)
358+ parenthesized (renderQuery q1)
422359 <+> "EXCEPT"
423− <+> parenthesized (renderSQL q2)
360+ <+> parenthesized (renderQuery q2)
424361
425362-- | The results of two queries can be combined using the set operation
426363-- `exceptAll`, the set difference. Duplicate rows are retained.
427364exceptAll
428− :: Query outer commons schemas params columns
429− -> Query outer commons schemas params columns
430− -> Query outer commons schemas params columns
365+ :: Query schema params columns
366+ -> Query schema params columns
367+ -> Query schema params columns
431368q1 `exceptAll` q2 = UnsafeQuery $
432− parenthesized (renderSQL q1)
369+ parenthesized (renderQuery q1)
433370 <+> "EXCEPT" <+> "ALL"
434− <+> parenthesized (renderSQL q2)
371+ <+> parenthesized (renderQuery q2)
435372
436373{-----------------------------------------
437374SELECT queries
438375-----------------------------------------}
439376
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−
525377-- | the `TableExpression` in the `select` command constructs an intermediate
526378-- virtual table by possibly combining tables, views, eliminating rows,
527379-- grouping, etc. This table is finally passed on to processing by
528−-- the select list. The `Selection` determines which columns of
380+-- the select list. The select list determines which columns of
529381-- the intermediate table are actually output.
530382select
531− :: (SListI row, row ~ (x ': xs))
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
383+ :: SListI columns
384+ => NP (Aliased (Expression schema relations grouping params)) (column ': columns)
547385 -- ^ select list
548− -> TableExpression outer commons grp schemas params from
386+ -> TableExpression schema params relations grouping
549387 -- ^ intermediate virtual table
550− -> Query outer commons schemas params row
551−select_ = select . List
388+ -> Query schema params (column ': columns)
389+select list rels = UnsafeQuery $
390+ "SELECT"
391+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list
392+ <+> renderTableExpression rels
552393
553394-- | After the select list has been processed, the result table can
554395-- be subject to the elimination of duplicate rows using `selectDistinct`.
555396selectDistinct
556− :: (SListI columns, columns ~ (col ': cols))
557− => Selection outer commons grp schemas params from columns
558− -- ^ selection
559− -> TableExpression outer commons grp schemas params from
397+ :: SListI columns
398+ => NP (Aliased (Expression schema relations 'Ungrouped params)) (column ': columns)
399+ -- ^ select list
400+ -> TableExpression schema params relations 'Ungrouped
560401 -- ^ intermediate virtual table
561− -> Query outer commons schemas params columns
562−selectDistinct selection tabexpr = UnsafeQuery $
402+ -> Query schema params (column ': columns)
403+selectDistinct list rels = UnsafeQuery $
563404 "SELECT DISTINCT"
564− <+> renderSQL selection
565− <+> renderSQL tabexpr
566−
567−-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead
568−-- of a general `Selection`.
569−selectDistinct_
570− :: (SListI columns, columns ~ (col ': cols))
571− => NP (Aliased (Expression outer commons grp schemas params from)) columns
572− -- ^ select list
573− -> TableExpression outer commons grp schemas params from
405+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list
406+ <+> renderTableExpression rels
407+
408+-- | The simplest kind of query is `selectStar` which emits all columns
409+-- that the table expression produces.
410+selectStar
411+ :: HasUnique relation relations columns
412+ => TableExpression schema params relations 'Ungrouped
574413 -- ^ intermediate virtual table
575− -> Query outer commons schemas params columns
576−selectDistinct_ = selectDistinct . List
577−
578−{-|
579−`selectDistinctOn` keeps only the first row of each set of rows where
580−the given expressions evaluate to equal. The DISTINCT ON expressions are
581−interpreted using the same rules as for ORDER BY. ORDER BY is used to
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
414+ -> Query schema params columns
415+selectStar rels = UnsafeQuery $ "SELECT" <+> "*" <+> renderTableExpression rels
416+
417+-- | A `selectDistinctStar` emits all columns that the table expression
418+-- produces and eliminates duplicate rows.
419+selectDistinctStar
420+ :: HasUnique relation relations columns
421+ => TableExpression schema params relations 'Ungrouped
598422 -- ^ intermediate virtual table
599− -> Query outer commons schemas params columns
600−selectDistinctOn distincts selection tab = UnsafeQuery $
601− "SELECT DISTINCT ON"
602− <+> parenthesized (commaSeparated (renderDistinctOn <$> distincts))
603− <+> renderSQL selection
604− <+> renderSQL (tab {orderByClause = distincts <> orderByClause tab})
605− where
606− renderDistinctOn = \case
607− Asc expression -> renderSQL expression
608− Desc expression -> renderSQL expression
609− AscNullsFirst expression -> renderSQL expression
610− DescNullsFirst expression -> renderSQL expression
611− AscNullsLast expression -> renderSQL expression
612− DescNullsLast expression -> renderSQL expression
613−
614−-- | Like `selectDistinctOn` but takes an `NP` list of `Expression`s instead
615−-- of a general `Selection`.
616−selectDistinctOn_
617− :: (SListI columns, columns ~ (col ': cols))
618− => [SortExpression outer commons grp schemas params from]
619− -- ^ distinct on and return the first row in ordering
620− -> NP (Aliased (Expression outer commons grp schemas params from)) columns
621− -- ^ selection
622− -> TableExpression outer commons grp schemas params from
423+ -> Query schema params columns
424+selectDistinctStar rels = UnsafeQuery $
425+ "SELECT DISTINCT" <+> "*" <+> renderTableExpression rels
426+
427+-- | When working with multiple tables, it can also be useful to ask
428+-- for all the columns of a particular table, using `selectDotStar`.
429+selectDotStar
430+ :: Has relation relations columns
431+ => Alias relation
432+ -- ^ particular virtual subtable
433+ -> TableExpression schema params relations 'Ungrouped
434+ -- ^ intermediate virtual table
435+ -> Query schema params columns
436+selectDotStar rel relations = UnsafeQuery $
437+ "SELECT" <+> renderAlias rel <> ".*" <+> renderTableExpression relations
438+
439+-- | A `selectDistinctDotStar` asks for all the columns of a particular table,
440+-- and eliminates duplicate rows.
441+selectDistinctDotStar
442+ :: Has relation relations columns
443+ => Alias relation
444+ -- ^ particular virtual table
445+ -> TableExpression schema params relations 'Ungrouped
623446 -- ^ intermediate virtual table
624− -> Query outer commons schemas params columns
625−selectDistinctOn_ distincts = selectDistinctOn distincts . List
447+ -> Query schema params columns
448+selectDistinctDotStar rel relations = UnsafeQuery $
449+ "SELECT DISTINCT" <+> renderAlias rel <> ".*"
450+ <+> renderTableExpression relations
626451
627452-- | `values` computes a row value or set of row values
628453-- specified by value expressions. It is most commonly used
@@ -630,16 +455,16 @@ selectDistinctOn_ distincts = selectDistinctOn distincts . List
630455-- but it can be used on its own.
631456--
632457-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]
633−-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query outer commons schemas '[] Row
458+-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query '[] '[] Row
634459-- >>> printSQL query
635460-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")
636461values
637462 :: SListI cols
638− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
639− -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]
463+ => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols
464+ -> [NP (Aliased (Expression schema '[] 'Ungrouped params)) cols]
640465 -- ^ When more than one row is specified, all the rows must
641466 -- must have the same number of elements
642− -> Query outer commons schemas params cols
467+ -> Query schema params cols
643468values rw rws = UnsafeQuery $ "SELECT * FROM"
644469 <+> parenthesized (
645470 "VALUES"
@@ -650,17 +475,17 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"
650475 <+> parenthesized (renderCommaSeparated renderAliasPart rw)
651476 where
652477 renderAliasPart, renderValuePart
653− :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString
654− renderAliasPart (_ `As` name) = renderSQL name
655− renderValuePart (value `As` _) = renderSQL value
478+ :: Aliased (Expression schema '[] 'Ungrouped params) ty -> ByteString
479+ renderAliasPart (_ `As` name) = renderAlias name
480+ renderValuePart (value `As` _) = renderExpression value
656481
657482-- | `values_` computes a row value or set of row values
658483-- specified by value expressions.
659484values_
660485 :: SListI cols
661− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
486+ => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols
662487 -- ^ one row of values
663− -> Query outer commons schemas params cols
488+ -> Query schema params cols
664489values_ rw = values rw []
665490
666491{-----------------------------------------
@@ -674,17 +499,15 @@ Table Expressions
674499-- to a table on disk, a so-called base table, but more complex expressions
675500-- can be used to modify or combine base tables in various ways.
676501data TableExpression
677− (outer :: FromType)
678− (commons :: FromType)
679− (grp :: Grouping)
680− (schemas :: SchemasType)
502+ (schema :: SchemaType)
681503 (params :: [NullityType])
682− (from :: FromType)
504+ (relations :: RelationsType)
505+ (grouping :: Grouping)
683506 = TableExpression
684− { fromClause :: FromClause outer commons schemas params from
507+ { fromClause :: FromClause schema params relations
685508 -- ^ A table reference that can be a table name, or a derived table such
686509 -- as a subquery, a @JOIN@ construct, or complex combinations of these.
687− , whereClause :: [Condition outer commons 'Ungrouped schemas params from]
510+ , whereClause :: [Condition schema relations 'Ungrouped params]
688511 -- ^ optional search coditions, combined with `.&&`. After the processing
689512 -- of the `fromClause` is done, each row of the derived virtual table
690513 -- is checked against the search condition. If the result of the
@@ -693,20 +516,20 @@ data TableExpression
693516 -- at least one column of the table generated in the `fromClause`;
694517 -- this is not required, but otherwise the WHERE clause will
695518 -- be fairly useless.
696− , groupByClause :: GroupByClause grp from
519+ , groupByClause :: GroupByClause relations grouping
697520 -- ^ The `groupByClause` is used to group together those rows in a table
698521 -- that have the same values in all the columns listed. The order in which
699522 -- the columns are listed does not matter. The effect is to combine each
700523 -- set of rows having common values into one group row that represents all
701524 -- rows in the group. This is done to eliminate redundancy in the output
702525 -- and/or compute aggregates that apply to these groups.
703− , havingClause :: HavingClause outer commons grp schemas params from
526+ , havingClause :: HavingClause schema relations grouping params
704527 -- ^ If a table has been grouped using `groupBy`, but only certain groups
705528 -- are of interest, the `havingClause` can be used, much like a
706529 -- `whereClause`, to eliminate groups from the result. Expressions in the
707530 -- `havingClause` can refer both to grouped expressions and to ungrouped
708531 -- expressions (which necessarily involve an aggregate function).
709− , orderByClause :: [SortExpression outer commons grp schemas params from]
532+ , orderByClause :: [SortExpression schema relations grouping params]
710533 -- ^ The `orderByClause` is for optional sorting. When more than one
711534 -- `SortExpression` is specified, the later (right) values are used to sort
712535 -- rows that are equal according to the earlier (left) values.
@@ -716,69 +539,72 @@ data TableExpression
716539 -- will be returned (but possibly fewer, if the query itself yields
717540 -- fewer rows).
718541 , offsetClause :: [Word64]
719− -- ^ The `offsetClause` is combined with `Prelude.+` to give an offset count
542+ -- ^ The `offsetClause` is combined with `+` to give an offset count
720543 -- if nonempty. The offset count says to skip that many rows before
721544 -- beginning to return rows. The rows are skipped before the limit count
722545 -- is applied.
723− } deriving (GHC.Generic)
546+ }
724547
725548-- | Render a `TableExpression`
726−instance RenderSQL (TableExpression outer commons grp schemas params from) where
727− renderSQL
728− (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat
729− [ "FROM ", renderSQL frm'
730− , renderWheres whs'
731− , renderSQL grps'
732− , renderSQL hvs'
733− , renderOrderByClause srts'
734− , renderLimits lims'
735− , renderOffsets offs' ]
736− where
737− renderWheres = \case
738− [] -> ""
739− wh:[] -> " WHERE" <+> renderSQL wh
740− wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)
741− renderOrderByClause = \case
742− [] -> ""
743− srts -> " ORDER BY"
744− <+> commaSeparated (renderSQL <$> srts)
745− renderLimits = \case
746− [] -> ""
747− lims -> " LIMIT" <+> fromString (show (minimum lims))
748− renderOffsets = \case
749− [] -> ""
750− offs -> " OFFSET" <+> fromString (show (sum offs))
549+renderTableExpression
550+ :: TableExpression schema params relations grouping
551+ -> ByteString
552+renderTableExpression
553+ (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat
554+ [ "FROM ", renderFromClause frm'
555+ , renderWheres whs'
556+ , renderGroupByClause grps'
557+ , renderHavingClause hvs'
558+ , renderOrderByClause srts'
559+ , renderLimits lims'
560+ , renderOffsets offs'
561+ ]
562+ where
563+ renderWheres = \case
564+ [] -> ""
565+ wh:[] -> " WHERE" <+> renderExpression wh
566+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)
567+ renderOrderByClause = \case
568+ [] -> ""
569+ srts -> " ORDER BY"
570+ <+> commaSeparated (renderSortExpression <$> srts)
571+ renderLimits = \case
572+ [] -> ""
573+ lims -> " LIMIT" <+> fromString (show (minimum lims))
574+ renderOffsets = \case
575+ [] -> ""
576+ offs -> " OFFSET" <+> fromString (show (sum offs))
751577
752578-- | A `from` generates a `TableExpression` from a table reference that can be
753579-- a table name, or a derived table such as a subquery, a JOIN construct,
754580-- or complex combinations of these. A `from` may be transformed by `where_`,
755−-- `groupBy`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator
581+-- `group`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator
756582-- to match the left-to-right sequencing of their placement in SQL.
757583from
758− :: FromClause outer commons schemas params from -- ^ table reference
759− -> TableExpression outer commons 'Ungrouped schemas params from
760−from tab = TableExpression tab [] noGroups NoHaving [] [] []
584+ :: FromClause schema params relations -- ^ table reference
585+ -> TableExpression schema params relations 'Ungrouped
586+from rels = TableExpression rels [] NoGroups NoHaving [] [] []
761587
762588-- | A `where_` is an endomorphism of `TableExpression`s which adds a
763589-- search condition to the `whereClause`.
764590where_
765− :: Condition outer commons 'Ungrouped schemas params from -- ^ filtering condition
766− -> TableExpression outer commons grp schemas params from
767− -> TableExpression outer commons grp schemas params from
591+ :: Condition schema relations 'Ungrouped params -- ^ filtering condition
592+ -> TableExpression schema params relations grouping
593+ -> TableExpression schema params relations grouping
768594where_ wh rels = rels {whereClause = wh : whereClause rels}
769595
770596-- | A `groupBy` is a transformation of `TableExpression`s which switches
771−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform
597+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform
772598-- a "grand total" aggregation query.
773599groupBy
774600 :: SListI bys
775− => NP (By from) bys -- ^ grouped columns
776− -> TableExpression outer commons 'Ungrouped schemas params from
777− -> TableExpression outer commons ('Grouped bys) schemas params from
601+ => NP (By relations) bys -- ^ grouped columns
602+ -> TableExpression schema params relations 'Ungrouped
603+ -> TableExpression schema params relations ('Grouped bys)
778604groupBy bys rels = TableExpression
779605 { fromClause = fromClause rels
780606 , whereClause = whereClause rels
781− , groupByClause = group bys
607+ , groupByClause = Group bys
782608 , havingClause = Having []
783609 , orderByClause = []
784610 , limitClause = limitClause rels
@@ -788,31 +614,219 @@ groupBy bys rels = TableExpression
788614-- | A `having` is an endomorphism of `TableExpression`s which adds a
789615-- search condition to the `havingClause`.
790616having
791− :: Condition outer commons ('Grouped bys) schemas params from -- ^ having condition
792− -> TableExpression outer commons ('Grouped bys) schemas params from
793− -> TableExpression outer commons ('Grouped bys) schemas params from
617+ :: Condition schema relations ('Grouped bys) params -- ^ having condition
618+ -> TableExpression schema params relations ('Grouped bys)
619+ -> TableExpression schema params relations ('Grouped bys)
794620having hv rels = rels
795621 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }
796622
797−instance OrderBy TableExpression where
798− orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}
623+-- | An `orderBy` is an endomorphism of `TableExpression`s which appends an
624+-- ordering to the right of the `orderByClause`.
625+orderBy
626+ :: [SortExpression schema relations grouping params] -- ^ sort expressions
627+ -> TableExpression schema params relations grouping
628+ -> TableExpression schema params relations grouping
629+orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}
799630
800631-- | A `limit` is an endomorphism of `TableExpression`s which adds to the
801632-- `limitClause`.
802633limit
803634 :: Word64 -- ^ limit parameter
804− -> TableExpression outer commons grp schemas params from
805− -> TableExpression outer commons grp schemas params from
635+ -> TableExpression schema params relations grouping
636+ -> TableExpression schema params relations grouping
806637limit lim rels = rels {limitClause = lim : limitClause rels}
807638
808639-- | An `offset` is an endomorphism of `TableExpression`s which adds to the
809640-- `offsetClause`.
810641offset
811642 :: Word64 -- ^ offset parameter
812− -> TableExpression outer commons grp schemas params from
813− -> TableExpression outer commons grp schemas params from
643+ -> TableExpression schema params relations grouping
644+ -> TableExpression schema params relations grouping
814645offset off rels = rels {offsetClause = off : offsetClause rels}
815646
647+{-----------------------------------------
648+JSON stuff
649+-----------------------------------------}
650+
651+type PGjson_each_variant val tab =
652+ '[ tab ::: '[ "key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull val ] ]
653+
654+-- | The type of a `json_each` `FromClause`.
655+type PGjson_each tab = PGjson_each_variant 'PGjson tab
656+-- | The type of a `jsonb_each` `FromClause`.
657+type PGjsonb_each tab = PGjson_each_variant 'PGjsonb tab
658+-- | The type of a `json_each_text` `FromClause`.
659+type PGjson_each_text tab = PGjson_each_variant 'PGtext tab
660+-- | The type of a `jsonb_each_text` `FromClause`.
661+type PGjsonb_each_text tab = PGjson_each_variant 'PGtext tab
662+
663+unsafeAliasedFromClauseExpression
664+ :: Aliased (Expression schema' relations' grouping' params') ty'
665+ -> FromClause schema params relations
666+unsafeAliasedFromClauseExpression aliasedExpr = UnsafeFromClause
667+ (renderAliasedAs renderExpression aliasedExpr)
668+
669+-- | Expands the outermost JSON object into a set of key/value pairs.
670+jsonEach
671+ :: Aliased (Expression schema '[] 'Ungrouped params) '(tab, nullity 'PGjson)
672+ -> FromClause schema params (PGjson_each tab)
673+jsonEach (As jexpr jname) = unsafeAliasedFromClauseExpression
674+ (As (unsafeFunction "json_each" jexpr) jname)
675+
676+-- | Expands the outermost binary JSON object into a set of key/value pairs.
677+jsonbEach
678+ :: Aliased (Expression schema '[] 'Ungrouped params) '(tab, nullity 'PGjsonb)
679+ -> FromClause schema params (PGjsonb_each tab)
680+jsonbEach (As jexpr jname) = unsafeAliasedFromClauseExpression
681+ (As (unsafeFunction "jsonb_each" jexpr) jname)
682+
683+-- | Expands the outermost JSON object into a set of key/value pairs.
684+jsonEachAsText
685+ :: Aliased (Expression schema '[] 'Ungrouped params) '(tab, nullity 'PGjson)
686+ -> FromClause schema params (PGjson_each_text tab)
687+jsonEachAsText (As jexpr jname) = unsafeAliasedFromClauseExpression
688+ (As (unsafeFunction "json_each" jexpr) jname)
689+
690+-- | Expands the outermost binary JSON object into a set of key/value pairs.
691+jsonbEachAsText
692+ :: Aliased (Expression schema '[] 'Ungrouped params) '(tab, nullity 'PGjsonb)
693+ -> FromClause schema params (PGjsonb_each_text tab)
694+jsonbEachAsText (As jexpr jname) = unsafeAliasedFromClauseExpression
695+ (As (unsafeFunction "jsonb_each" jexpr) jname)
696+
697+nullRow
698+ :: Has tab schema ('Table table)
699+ => Alias tab
700+ -> Expression schema relations grouping params
701+ (nullity ('PGcomposite (RelationToRowType (TableToRelation table))))
702+nullRow tab = UnsafeExpression ("null::"<+>renderAlias tab)
703+
704+-- | Expands the JSON expression to a row whose columns match the record
705+-- type defined by the given table.
706+jsonPopulateRecordAs
707+ :: (KnownSymbol alias, Has tab schema ('Table table))
708+ => Alias tab
709+ -> Expression schema '[] 'Ungrouped params (nullity 'PGjson)
710+ -> Alias alias
711+ -> FromClause schema params '[alias ::: TableToRelation table]
712+jsonPopulateRecordAs tableName expr alias = unsafeAliasedFromClauseExpression
713+ (unsafeVariadicFunction "json_populate_record"
714+ (nullRow tableName :* expr :* Nil) `As` alias)
715+
716+-- | Expands the binary JSON expression to a row whose columns match the record
717+-- type defined by the given table.
718+jsonbPopulateRecordAs
719+ :: (KnownSymbol alias, Has tab schema ('Table table))
720+ => Alias tab
721+ -> Expression schema '[] 'Ungrouped params (nullity 'PGjsonb)
722+ -> Alias alias
723+ -> FromClause schema params '[alias ::: TableToRelation table]
724+jsonbPopulateRecordAs tableName expr alias = unsafeAliasedFromClauseExpression
725+ (unsafeVariadicFunction "jsonb_populate_record"
726+ (nullRow tableName :* expr :* Nil) `As` alias)
727+
728+-- | Expands the outermost array of objects in the given JSON expression to a
729+-- set of rows whose columns match the record type defined by the given table.
730+jsonPopulateRecordSetAs
731+ :: (KnownSymbol alias, Has tab schema ('Table table))
732+ => Alias tab
733+ -> Expression schema '[] 'Ungrouped params (nullity 'PGjson)
734+ -> Alias alias
735+ -> FromClause schema params '[alias ::: TableToRelation table]
736+jsonPopulateRecordSetAs tableName expr alias = unsafeAliasedFromClauseExpression
737+ (unsafeVariadicFunction "json_populate_record_set"
738+ (nullRow tableName :* expr :* Nil) `As` alias)
739+
740+-- | Expands the outermost array of objects in the given binary JSON expression
741+-- to a set of rows whose columns match the record type defined by the given
742+-- table.
743+jsonbPopulateRecordSetAs
744+ :: (KnownSymbol alias, Has tab schema ('Table table))
745+ => Alias tab
746+ -> Expression schema '[] 'Ungrouped params (nullity 'PGjsonb)
747+ -> Alias alias
748+ -> FromClause schema params '[alias ::: TableToRelation table]
749+jsonbPopulateRecordSetAs tableName expr alias = unsafeAliasedFromClauseExpression
750+ (unsafeVariadicFunction "jsonb_populate_record_set"
751+ (nullRow tableName :* expr :* Nil) `As` alias)
752+
753+renderTableTypeExpression
754+ :: All Top types
755+ => Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
756+ -> ByteString
757+renderTableTypeExpression (hc `As` tab)
758+ = (renderAlias tab <>)
759+ . parenthesized
760+ . commaSeparated
761+ . flip appEndo []
762+ . hcfoldMap
763+ (Proxy :: Proxy Top)
764+ (\(ty `As` name) -> Endo
765+ ((renderAlias name <+> renderTypeExpression ty):))
766+ $ hc
767+
768+unsafeTableAliasedFromClauseExpression
769+ :: All Top types
770+ => Expression schema' relations' grouping' params' ty'
771+ -> Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
772+ -> FromClause schema params '[alias ::: types]
773+unsafeTableAliasedFromClauseExpression expr types = UnsafeFromClause
774+ (renderExpression expr
775+ <+> "AS"
776+ <+> renderTableTypeExpression types)
777+
778+-- | Builds an arbitrary record from a JSON object. As with all functions
779+-- returning record, the caller must explicitly define the structure of the
780+-- record with an AS clause.
781+jsonToRecordAs
782+ :: All Top types
783+ => Expression schema '[] 'Ungrouped params (nullity 'PGjson)
784+ -> Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
785+ -> FromClause schema params '[tab ::: types]
786+jsonToRecordAs expr types =
787+ unsafeTableAliasedFromClauseExpression
788+ (unsafeFunction "json_to_record" expr)
789+ types
790+
791+-- | Builds an arbitrary record from a binary JSON object. As with all functions
792+-- returning record, the caller must explicitly define the structure of the
793+-- record with an AS clause.
794+jsonbToRecordAs
795+ :: All Top types
796+ => Expression schema '[] 'Ungrouped params (nullity 'PGjsonb)
797+ -> Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
798+ -> FromClause schema params '[tab ::: types]
799+jsonbToRecordAs expr types =
800+ unsafeTableAliasedFromClauseExpression
801+ (unsafeFunction "jsonb_to_record" expr)
802+ types
803+
804+-- | Builds an arbitrary set of records from a JSON array of objects (see note
805+-- below). As with all functions returning record, the caller must explicitly
806+-- define the structure of the record with an AS clause.
807+jsonToRecordSetAs
808+ :: All Top types
809+ => Expression schema '[] 'Ungrouped params (nullity 'PGjson)
810+ -> Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
811+ -> FromClause schema params '[tab ::: types]
812+jsonToRecordSetAs expr types =
813+ unsafeTableAliasedFromClauseExpression
814+ (unsafeFunction "json_to_recordset" expr)
815+ types
816+
817+-- | Builds an arbitrary set of records from a binary JSON array of objects (see
818+-- note below). As with all functions returning record, the caller must
819+-- explicitly define the structure of the record with an AS clause.
820+jsonbToRecordSetAs
821+ :: All Top types
822+ => Expression schema '[] 'Ungrouped params (nullity 'PGjsonb)
823+ -> Aliased (NP (Aliased (TypeExpression schema))) (tab ::: types)
824+ -> FromClause schema params '[tab ::: types]
825+jsonbToRecordSetAs expr types =
826+ unsafeTableAliasedFromClauseExpression
827+ (unsafeFunction "jsonb_to_recordset" expr)
828+ types
829+
816830{-----------------------------------------
817831FROM clauses
818832-----------------------------------------}
@@ -821,76 +835,61 @@ FROM clauses
821835A `FromClause` can be a table name, or a derived table such
822836as a subquery, a @JOIN@ construct, or complex combinations of these.
823837-}
824−newtype FromClause outer commons schemas params from
838+newtype FromClause schema params relations
825839 = UnsafeFromClause { renderFromClause :: ByteString }
826840 deriving (GHC.Generic,Show,Eq,Ord,NFData)
827−instance RenderSQL (FromClause outer commons schemas params from) where
828− renderSQL = renderFromClause
829841
830−-- | A real `table` is a table from the database.
842+-- | A real `table` is a table from the schema.
831843table
832− :: (Has sch schemas schema, Has tab schema ('Table table))
833− => Aliased (QualifiedAlias sch) (alias ::: tab)
834− -> FromClause outer commons schemas params '[alias ::: TableToRow table]
844+ :: Has tab schema ('Table table)
845+ => Aliased Alias (alias ::: tab)
846+ -> FromClause schema params '[alias ::: TableToRelation table]
835847table (tab `As` alias) = UnsafeFromClause $
836− renderSQL tab <+> "AS" <+> renderSQL alias
848+ renderAlias tab <+> "AS" <+> renderAlias alias
837849
838850-- | `subquery` derives a table from a `Query`.
839851subquery
840− :: Aliased (Query outer commons schemas params) query
841− -> FromClause outer commons schemas params '[query]
842−subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)
852+ :: Aliased (Query schema params) rel
853+ -> FromClause schema params '[rel]
854+subquery = UnsafeFromClause . renderAliasedAs (parenthesized . renderQuery)
843855
844856-- | `view` derives a table from a `View`.
845857view
846− :: (Has sch schemas schema, Has vw schema ('View view))
847− => Aliased (QualifiedAlias sch) (alias ::: vw)
848− -> FromClause outer commons schemas params '[alias ::: view]
858+ :: Has view schema ('View rel)
859+ => Aliased Alias (alias ::: view)
860+ -> FromClause schema params '[alias ::: rel]
849861view (vw `As` alias) = UnsafeFromClause $
850− renderSQL vw <+> "AS" <+> renderSQL 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−
860−instance Additional (FromClause outer commons schemas params) where
861− also right left = UnsafeFromClause $
862− renderSQL left <> ", " <> renderSQL right
862+ renderAlias vw <+> "AS" <+> renderAlias alias
863863
864−{- |
865−@left & crossJoin right@. For every possible combination of rows from
866−@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@.
868−If the tables have @n@ and @m@ rows respectively, the joined table will
869−have @n * m@ rows.
864+{- | @left & crossJoin right@. For every possible combination of rows from
865+ @left@ and @right@ (i.e., a Cartesian product), the joined table will contain
866+ a row consisting of all columns in @left@ followed by all columns in @right@.
867+ If the tables have @n@ and @m@ rows respectively, the joined table will
868+ have @n * m@ rows.
870869-}
871870crossJoin
872− :: FromClause outer commons schemas params right
871+ :: FromClause schema params right
873872 -- ^ right
874− -> FromClause outer commons schemas params left
873+ -> FromClause schema params left
875874 -- ^ left
876− -> FromClause outer commons schemas params (Join left right)
875+ -> FromClause schema params (Join left right)
877876crossJoin right left = UnsafeFromClause $
878− renderSQL left <+> "CROSS JOIN" <+> renderSQL right
877+ renderFromClause left <+> "CROSS JOIN" <+> renderFromClause right
879878
880879{- | @left & innerJoin right on@. The joined table is filtered by
881880the @on@ condition.
882881-}
883882innerJoin
884− :: FromClause outer commons schemas params right
883+ :: FromClause schema params right
885884 -- ^ right
886− -> Condition outer commons 'Ungrouped schemas params (Join left right)
885+ -> Condition schema (Join left right) 'Ungrouped params
887886 -- ^ @on@ condition
888− -> FromClause outer commons schemas params left
887+ -> FromClause schema params left
889888 -- ^ left
890− -> FromClause outer commons schemas params (Join left right)
889+ -> FromClause schema params (Join left right)
891890innerJoin right on left = UnsafeFromClause $
892− renderSQL left <+> "INNER JOIN" <+> renderSQL right
893− <+> "ON" <+> renderSQL on
891+ renderFromClause left <+> "INNER JOIN" <+> renderFromClause right
892+ <+> "ON" <+> renderExpression on
894893
895894{- | @left & leftOuterJoin right on@. First, an inner join is performed.
896895 Then, for each row in @left@ that does not satisfy the @on@ condition with
@@ -898,16 +897,16 @@ innerJoin right on left = UnsafeFromClause $
898897 Thus, the joined table always has at least one row for each row in @left@.
899898-}
900899leftOuterJoin
901− :: FromClause outer commons schemas params right
900+ :: FromClause schema params right
902901 -- ^ right
903− -> Condition outer commons 'Ungrouped schemas params (Join left right)
902+ -> Condition schema (Join left right) 'Ungrouped params
904903 -- ^ @on@ condition
905− -> FromClause outer commons schemas params left
904+ -> FromClause schema params left
906905 -- ^ left
907− -> FromClause outer commons schemas params (Join left (NullifyFrom right))
906+ -> FromClause schema params (Join left (NullifyRelations right))
908907leftOuterJoin right on left = UnsafeFromClause $
909− renderSQL left <+> "LEFT OUTER JOIN" <+> renderSQL right
910− <+> "ON" <+> renderSQL on
908+ renderFromClause left <+> "LEFT OUTER JOIN" <+> renderFromClause right
909+ <+> "ON" <+> renderExpression on
911910
912911{- | @left & rightOuterJoin right on@. First, an inner join is performed.
913912 Then, for each row in @right@ that does not satisfy the @on@ condition with
@@ -916,16 +915,16 @@ leftOuterJoin right on left = UnsafeFromClause $
916915 have a row for each row in @right@.
917916-}
918917rightOuterJoin
919− :: FromClause outer commons schemas params right
918+ :: FromClause schema params right
920919 -- ^ right
921− -> Condition outer commons 'Ungrouped schemas params (Join left right)
920+ -> Condition schema (Join left right) 'Ungrouped params
922921 -- ^ @on@ condition
923− -> FromClause outer commons schemas params left
922+ -> FromClause schema params left
924923 -- ^ left
925− -> FromClause outer commons schemas params (Join (NullifyFrom left) right)
924+ -> FromClause schema params (Join (NullifyRelations left) right)
926925rightOuterJoin right on left = UnsafeFromClause $
927− renderSQL left <+> "RIGHT OUTER JOIN" <+> renderSQL right
928− <+> "ON" <+> renderSQL on
926+ renderFromClause left <+> "RIGHT OUTER JOIN" <+> renderFromClause right
927+ <+> "ON" <+> renderExpression on
929928
930929{- | @left & fullOuterJoin right on@. First, an inner join is performed.
931930 Then, for each row in @left@ that does not satisfy the @on@ condition with
@@ -935,46 +934,42 @@ rightOuterJoin right on left = UnsafeFromClause $
935934 is added.
936935-}
937936fullOuterJoin
938− :: FromClause outer commons schemas params right
937+ :: FromClause schema params right
939938 -- ^ right
940− -> Condition outer commons 'Ungrouped schemas params (Join left right)
939+ -> Condition schema (Join left right) 'Ungrouped params
941940 -- ^ @on@ condition
942− -> FromClause outer commons schemas params left
941+ -> FromClause schema params left
943942 -- ^ left
944− -> FromClause outer commons schemas params
945− (Join (NullifyFrom left) (NullifyFrom right))
943+ -> FromClause schema params
944+ (Join (NullifyRelations left) (NullifyRelations right))
946945fullOuterJoin right on left = UnsafeFromClause $
947− renderSQL left <+> "FULL OUTER JOIN" <+> renderSQL right
948− <+> "ON" <+> renderSQL on
946+ renderFromClause left <+> "FULL OUTER JOIN" <+> renderFromClause right
947+ <+> "ON" <+> renderExpression on
949948
950949{-----------------------------------------
951950Grouping
952951-----------------------------------------}
953952
954−-- | `By`s are used in `groupBy` to reference a list of columns which are then
953+-- | `By`s are used in `group` to reference a list of columns which are then
955954-- used to group together those rows in a table that have the same values
956955-- in all the columns listed. @By \#col@ will reference an unambiguous
957956-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table
958957-- qualified column @tab.col@.
959958data By
960− (from :: FromType)
959+ (relations :: RelationsType)
961960 (by :: (Symbol,Symbol)) where
962961 By1
963− :: (HasUnique table from columns, Has column columns ty)
962+ :: (HasUnique relation relations columns, Has column columns ty)
964963 => Alias column
965− -> By from '(table, column)
964+ -> By relations '(relation, column)
966965 By2
967− :: (Has table from columns, Has column columns ty)
968− => Alias table
966+ :: (Has relation relations columns, Has column columns ty)
967+ => Alias relation
969968 -> Alias column
970− -> By from '(table, column)
971−deriving instance Show (By from by)
972−deriving instance Eq (By from by)
973−deriving instance Ord (By from by)
974−instance RenderSQL (By from by) where
975− renderSQL = \case
976− By1 column -> renderSQL column
977− By2 rel column -> renderSQL rel <> "." <> renderSQL column
969+ -> By relations '(relation, column)
970+deriving instance Show (By relations by)
971+deriving instance Eq (By relations by)
972+deriving instance Ord (By relations by)
978973
979974instance (HasUnique rel rels cols, Has col cols ty, by ~ '(rel, col))
980975 => IsLabel col (By rels by) where fromLabel = By1 fromLabel
@@ -986,113 +981,94 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])
986981 => IsQualified rel col (NP (By rels) bys) where
987982 rel ! col = By2 rel col :* Nil
988983
984+-- | Renders a `By`.
985+renderBy :: By relations by -> ByteString
986+renderBy = \case
987+ By1 column -> renderAlias column
988+ By2 rel column -> renderAlias rel <> "." <> renderAlias column
989+
989990-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.
990991-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.
991992-- @NoGroups@ is distinguised from @Group Nil@ since no aggregation can be
992993-- done on @NoGroups@ while all output `Expression`s must be aggregated
993994-- in @Group Nil@. In general, all output `Expression`s in the
994995-- complement of @bys@ must be aggregated in @Group bys@.
995−newtype GroupByClause grp from = UnsafeGroupByClause
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
1001−noGroups = UnsafeGroupByClause ""
1002−group
1003− :: SListI bys
1004− => NP (By from) bys
1005− -> GroupByClause ('Grouped bys) from
1006−group bys = UnsafeGroupByClause $ case bys of
1007− Nil -> ""
1008− bys' -> " GROUP BY" <+> renderCommaSeparated renderSQL bys'
996+data GroupByClause relations grouping where
997+ NoGroups :: GroupByClause relations 'Ungrouped
998+ Group
999+ :: SListI bys
1000+ => NP (By relations) bys
1001+ -> GroupByClause relations ('Grouped bys)
1002+
1003+-- | Renders a `GroupByClause`.
1004+renderGroupByClause :: GroupByClause relations grouping -> ByteString
1005+renderGroupByClause = \case
1006+ NoGroups -> ""
1007+ Group Nil -> ""
1008+ Group bys -> " GROUP BY" <+> renderCommaSeparated renderBy bys
10091009
10101010-- | A `HavingClause` is used to eliminate groups that are not of interest.
10111011-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`
10121012-- `TableExpression` must use `Having` whose conditions are combined with
10131013-- `.&&`.
1014−data HavingClause outer commons grp schemas params from where
1015− NoHaving :: HavingClause outer commons 'Ungrouped schemas params from
1014+data HavingClause schema relations grouping params where
1015+ NoHaving :: HavingClause schema relations 'Ungrouped params
10161016 Having
1017− :: [Condition outer commons ('Grouped bys) schemas params from]
1018− -> HavingClause outer commons ('Grouped bys) schemas params from
1019−deriving instance Show (HavingClause outer commons grp schemas params from)
1020−deriving instance Eq (HavingClause outer commons grp schemas params from)
1021−deriving instance Ord (HavingClause outer commons grp schemas params from)
1017+ :: [Condition schema relations ('Grouped bys) params]
1018+ -> HavingClause schema relations ('Grouped bys) params
1019+deriving instance Show (HavingClause schema relations grouping params)
1020+deriving instance Eq (HavingClause schema relations grouping params)
1021+deriving instance Ord (HavingClause schema relations grouping params)
10221022
10231023-- | Render a `HavingClause`.
1024−instance RenderSQL (HavingClause outer commons grp schemas params from) where
1025− renderSQL = \case
1026− NoHaving -> ""
1027− Having [] -> ""
1028− Having conditions ->
1029− " HAVING" <+> commaSeparated (renderSQL <$> 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
1024+renderHavingClause :: HavingClause schema relations grouping params -> ByteString
1025+renderHavingClause = \case
1026+ NoHaving -> ""
1027+ Having [] -> ""
1028+ Having conditions ->
1029+ " HAVING" <+> commaSeparated (renderExpression <$> conditions)
10741030
1075−{- |
1076−>>> import Data.Monoid (Sum (..))
1077−>>> import Data.Int (Int64)
1078−>>> :{
1079− let
1080− query :: Query_ schema () (Sum Int64)
1081− query = withRecursive
1082− ( values_ ((1 & astype int) `as` #n)
1083− `unionAll`
1084− select_ ((#n + 1) `as` #n)
1085− (from (common #t) & where_ (#n .< 100)) `as` #t )
1086− ( select_ (fromNull 0 (sum_ (All #n)) `as` #getSum) (from (common #t) & groupBy Nil))
1087− in printSQL query
1088−:}
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"
1090−-}
1091−withRecursive
1092− :: Aliased (Query outer (recursive ': commons) schemas params) recursive
1093− -> Query outer (recursive ': commons) schemas params row
1094− -> Query outer commons schemas params row
1095−withRecursive (recursive `As` cte) query = UnsafeQuery $
1096− "WITH RECURSIVE" <+> renderSQL cte
1097− <+> "AS" <+> parenthesized (renderSQL recursive)
1098− <+> renderSQL query
1031+{-----------------------------------------
1032+Sorting
1033+-----------------------------------------}
1034+
1035+-- | `SortExpression`s are used by `sortBy` to optionally sort the results
1036+-- of a `Query`. `Asc` or `Desc` set the sort direction of a `NotNull` result
1037+-- column to ascending or descending. Ascending order puts smaller values
1038+-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,
1039+-- descending order is determined with the `.>` operator. `AscNullsFirst`,
1040+-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to
1041+-- determine whether nulls appear before or after non-null values in the sort
1042+-- ordering of a `Null` result column.
1043+data SortExpression schema relations grouping params where
1044+ Asc
1045+ :: Expression schema relations grouping params ('NotNull ty)
1046+ -> SortExpression schema relations grouping params
1047+ Desc
1048+ :: Expression schema relations grouping params ('NotNull ty)
1049+ -> SortExpression schema relations grouping params
1050+ AscNullsFirst
1051+ :: Expression schema relations grouping params ('Null ty)
1052+ -> SortExpression schema relations grouping params
1053+ AscNullsLast
1054+ :: Expression schema relations grouping params ('Null ty)
1055+ -> SortExpression schema relations grouping params
1056+ DescNullsFirst
1057+ :: Expression schema relations grouping params ('Null ty)
1058+ -> SortExpression schema relations grouping params
1059+ DescNullsLast
1060+ :: Expression schema relations grouping params ('Null ty)
1061+ -> SortExpression schema relations grouping params
1062+deriving instance Show (SortExpression schema relations grouping params)
1063+
1064+-- | Render a `SortExpression`.
1065+renderSortExpression :: SortExpression schema relations grouping params -> ByteString
1066+renderSortExpression = \case
1067+ Asc expression -> renderExpression expression <+> "ASC"
1068+ Desc expression -> renderExpression expression <+> "DESC"
1069+ AscNullsFirst expression -> renderExpression expression
1070+ <+> "ASC NULLS FIRST"
1071+ DescNullsFirst expression -> renderExpression expression
1072+ <+> "DESC NULLS FIRST"
1073+ AscNullsLast expression -> renderExpression expression <+> "ASC NULLS LAST"
1074+ DescNullsLast expression -> renderExpression expression <+> "DESC NULLS LAST"
squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+17−58
@@ -9,48 +9,39 @@ Rendering helper functions.
99-}
1010
1111{-# LANGUAGE
12− AllowAmbiguousTypes
13− , ConstraintKinds
14− , FlexibleContexts
15− , LambdaCase
12+ FlexibleContexts
1613 , MagicHash
1714 , OverloadedStrings
1815 , PolyKinds
1916 , RankNTypes
2017 , ScopedTypeVariables
21− , TypeApplications
2218#-}
2319
2420module Squeal.PostgreSQL.Render
2521 ( -- * Render
26− RenderSQL (..)
27− , printSQL
28− , escape
29− , parenthesized
30− , bracketed
22+ parenthesized
3123 , (<+>)
3224 , commaSeparated
3325 , doubleQuoted
3426 , singleQuotedText
3527 , singleQuotedUtf8
3628 , renderCommaSeparated
37− , renderCommaSeparatedConstraint
3829 , renderCommaSeparatedMaybe
3930 , renderNat
40− , renderSymbol
31+ , RenderSQL (..)
32+ , printSQL
4133 ) where
4234
43−import Control.Monad.IO.Class (MonadIO (..))
35+import Control.Monad.Base
4436import Data.ByteString (ByteString)
45−import Data.Maybe (catMaybes)
37+import Data.Maybe
4638import Data.Monoid ((<>))
4739import Data.Text (Text)
4840import Generics.SOP
4941import GHC.Exts
50−import GHC.TypeLits hiding (Text)
51−
52−import qualified Data.Text as Text
53−import qualified Data.Text.Encoding as Text
42+import GHC.TypeLits
43+import qualified Data.Text as T
44+import qualified Data.Text.Encoding as T
5445import qualified Data.ByteString as ByteString
5546import qualified Data.ByteString.Char8 as Char8
5647
@@ -58,13 +49,8 @@ import qualified Data.ByteString.Char8 as Char8
5849parenthesized :: ByteString -> ByteString
5950parenthesized str = "(" <> str <> ")"
6051
61−-- | Square bracket a `ByteString`
62−bracketed :: ByteString -> ByteString
63−bracketed str = "[" <> str <> "]"
64−
6552-- | Concatenate two `ByteString`s with a space between.
6653(<+>) :: ByteString -> ByteString -> ByteString
67−infixr 7 <+>
6854str1 <+> str2 = str1 <> " " <> str2
6955
7056-- | Comma separate a list of `ByteString`s.
@@ -77,12 +63,11 @@ doubleQuoted str = "\"" <> str <> "\""
7763
7864-- | Add single quotes around a `Text` and escape single quotes within it.
7965singleQuotedText :: Text -> ByteString
80−singleQuotedText str =
81− "'" <> Text.encodeUtf8 (Text.replace "'" "''" str) <> "'"
66+singleQuotedText str = "'" <> T.encodeUtf8 (T.replace "'" "''" str) <> "'"
8267
8368-- | Add single quotes around a `ByteString` and escape single quotes within it.
8469singleQuotedUtf8 :: ByteString -> ByteString
85−singleQuotedUtf8 = singleQuotedText . Text.decodeUtf8
70+singleQuotedUtf8 = singleQuotedText . T.decodeUtf8
8671
8772-- | Comma separate the renderings of a heterogeneous list.
8873renderCommaSeparated
@@ -94,16 +79,6 @@ renderCommaSeparated render
9479 . hcollapse
9580 . hmap (K . render)
9681
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−
10782-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping
10883-- `Nothing`s.
10984renderCommaSeparatedMaybe
@@ -117,29 +92,13 @@ renderCommaSeparatedMaybe render
11792 . hmap (K . render)
11893
11994-- | Render a promoted `Nat`.
120−renderNat :: forall n. KnownNat n => ByteString
121−renderNat = 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))
95+renderNat :: KnownNat n => proxy n -> ByteString
96+renderNat (_ :: proxy n) = fromString (show (natVal' (proxy# :: Proxy# n)))
12697
12798-- | A class for rendering SQL
128−class RenderSQL sql where renderSQL :: sql -> ByteString
99+class RenderSQL sql where
100+ renderSQL :: sql -> ByteString
129101
130102-- | Print SQL.
131−printSQL :: (RenderSQL sql, MonadIO io) => sql -> io ()
132−printSQL = liftIO . 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]
103+printSQL :: (RenderSQL sql, MonadBase IO io) => sql -> io ()
104+printSQL = liftBase . Char8.putStrLn . renderSQL
squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+635−310
@@ -1,15 +1,16 @@
11{-|
22Module: Squeal.PostgreSQL.Schema
33Description: Embedding of PostgreSQL type and alias system
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
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,
99tables, schema, constraints, aliases, enumerated labels, and groupings.
1010It also defines useful type families to operate on these. Finally,
1111it defines an embedding of Haskell types into Postgres types.
1212-}
13+{-# OPTIONS_GHC -fno-warn-unticked-promoted-constructors #-}
1314{-# LANGUAGE
1415 AllowAmbiguousTypes
1516 , ConstraintKinds
@@ -19,9 +20,7 @@ it defines an embedding of Haskell types into Postgres types.
1920 , FlexibleInstances
2021 , FunctionalDependencies
2122 , GADTs
22− , LambdaCase
2323 , OverloadedStrings
24− , QuantifiedConstraints
2524 , RankNTypes
2625 , ScopedTypeVariables
2726 , StandaloneDeriving
@@ -34,85 +33,132 @@ it defines an embedding of Haskell types into Postgres types.
3433#-}
3534
3635module Squeal.PostgreSQL.Schema
37− ( -- * Postgres Types
36+ ( -- * Types
3837 PGType (..)
38+ , HasOid (..)
3939 , NullityType (..)
40− , RowType
41− , FromType
42− -- * Schema Types
4340 , ColumnType
41+ -- * Tables
4442 , ColumnsType
43+ , RelationType
44+ , NilRelation
45+ , RelationsType
4546 , TableType
47+ -- * Schema
4648 , SchemumType (..)
47− , IndexType (..)
48− , FunctionType
49− , OperatorType (..)
50− , ReturnsType (..)
5149 , SchemaType
52− , SchemasType
53− , Public
5450 -- * Constraints
5551 , (:=>)
5652 , ColumnConstraint (..)
5753 , TableConstraint (..)
5854 , TableConstraints
55+ , NilTableConstraints
5956 , Uniquely
57+ -- * Aliases
58+ , (:::)
59+ , Alias (Alias)
60+ , renderAlias
61+ , renderAliases
62+ , Aliased (As)
63+ , Aliasable (as)
64+ , renderAliasedAs
65+ , AliasesOf
66+ , ZipAliased (..)
67+ , Has
68+ , HasUnique
69+ , HasAll
70+ , IsLabel (..)
71+ , IsQualified (..)
72+ , renderAliasString
6073 -- * Enumerated Labels
6174 , IsPGlabel (..)
6275 , PGlabel (..)
63− -- * Data Definitions
76+ , renderLabel
77+ , renderLabels
78+ -- * Grouping
79+ , Grouping (..)
80+ , GroupedBy
81+ -- * Type Families
82+ , Join
83+ , With
6484 , Create
65− , CreateIfNotExists
66− , CreateOrReplace
6785 , Drop
68− , DropSchemum
69− , DropIfExists
70− , DropSchemumIfExists
7186 , Alter
72− , AlterIfExists
7387 , Rename
74− , RenameIfExists
75− , ConstraintInvolves
76− , DropIfConstraintsInvolve
77− , IsNotElem
78− , AllUnique
79− -- * Type Classifications
88+ , Elem
89+ , In
8090 , PGNum
8191 , PGIntegral
8292 , PGFloating
8393 , PGTypeOf
84− , PGJsonType
85− , PGJsonKey
94+ , PGarrayOf
95+ , PGarray
96+ , PGtextArray
97+ , SameTypes
8698 , SamePGType
8799 , AllNotNull
88100 , NotAllNull
89− -- * Nullifications
90101 , NullifyType
91− , NullifyRow
92− , NullifyFrom
93− -- * Table Conversions
102+ , NullifyRelation
103+ , NullifyRelations
104+ , ColumnsToRelation
94105 , TableToColumns
95− , ColumnsToRow
96− , TableToRow
106+ , TableToRelation
107+ , RelationToRowType
108+ , RelationToNullityTypes
109+ , ConstraintInvolves
110+ , DropIfConstraintsInvolve
111+ -- ** JSON support
112+ , PGjson_
113+ , PGjsonKey
114+ -- * Embedding
115+ , PG
116+ , EnumFrom
117+ , LabelsFrom
118+ , CompositeFrom
119+ , FieldNamesFrom
120+ , FieldTypesFrom
121+ , ConstructorsOf
122+ , ConstructorNameOf
123+ , ConstructorNamesOf
124+ , FieldsOf
125+ , FieldNameOf
126+ , FieldNamesOf
127+ , FieldTypeOf
128+ , FieldTypesOf
129+ , RecordCodeOf
130+ , MapMaybes (..)
131+ , Nulls
97132 ) where
98133
99−import Control.Category
134+import Control.DeepSeq
135+import Data.Aeson (Value)
136+import Data.ByteString (ByteString)
137+import Data.Int (Int16, Int32, Int64)
100138import Data.Kind
101139import Data.Monoid hiding (All)
140+import Data.Scientific (Scientific)
141+import Data.String
142+import Data.Text (Text)
143+import Data.Time
144+import Data.Word (Word16, Word32, Word64)
102145import Data.Type.Bool
146+import Data.UUID.Types (UUID)
103147import Generics.SOP
148+import GHC.OverloadedLabels
104149import GHC.TypeLits
105−import Prelude hiding (id, (.))
150+import Network.IP.Addr
106151
107−import Squeal.PostgreSQL.Alias
108−import Squeal.PostgreSQL.List
109−import Squeal.PostgreSQL.Render
152+import qualified Data.ByteString.Lazy as Lazy
153+import qualified Data.Text.Lazy as Lazy
154+import qualified GHC.Generics as GHC
155+import qualified Generics.SOP.Type.Metadata as Type
110156
111−-- $setup
112−-- >>> import Squeal.PostgreSQL
157+import Squeal.PostgreSQL.Render
113158
114159-- | `PGType` is the promoted datakind of PostgreSQL types.
115160--
161+-- >>> import Squeal.PostgreSQL.Schema
116162-- >>> :kind 'PGbool
117163-- 'PGbool :: PGType
118164data PGType
@@ -123,7 +169,6 @@ data PGType
123169 | PGnumeric -- ^ arbitrary precision numeric type
124170 | PGfloat4 -- ^ single precision floating-point number (4 bytes)
125171 | PGfloat8 -- ^ double precision floating-point number (8 bytes)
126− | PGmoney -- ^ currency amount
127172 | PGchar Nat -- ^ fixed-length character string
128173 | PGvarchar Nat -- ^ variable-length character string
129174 | PGtext -- ^ variable-length character string
@@ -138,16 +183,40 @@ data PGType
138183 | PGinet -- ^ IPv4 or IPv6 host address
139184 | PGjson -- ^ textual JSON data
140185 | PGjsonb -- ^ binary JSON data, decomposed
141− | PGvararray NullityType -- ^ variable length array
142− | PGfixarray [Nat] NullityType -- ^ fixed length array
143− | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.
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.
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).
186+ | PGvararray PGType -- ^ variable length array
187+ | PGfixarray Nat PGType -- ^ fixed length array
188+ | PGenum [Symbol]
189+ | PGcomposite [(Symbol, PGType)]
149190 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types
150191
192+-- | The object identifier of a `PGType`.
193+--
194+-- >>> :set -XTypeApplications
195+-- >>> oid @'PGbool
196+-- 16
197+class HasOid (ty :: PGType) where oid :: Word32
198+instance HasOid 'PGbool where oid = 16
199+instance HasOid 'PGint2 where oid = 21
200+instance HasOid 'PGint4 where oid = 23
201+instance HasOid 'PGint8 where oid = 20
202+instance HasOid 'PGnumeric where oid = 1700
203+instance HasOid 'PGfloat4 where oid = 700
204+instance HasOid 'PGfloat8 where oid = 701
205+instance HasOid ('PGchar n) where oid = 18
206+instance HasOid ('PGvarchar n) where oid = 1043
207+instance HasOid 'PGtext where oid = 25
208+instance HasOid 'PGbytea where oid = 17
209+instance HasOid 'PGtimestamp where oid = 1114
210+instance HasOid 'PGtimestamptz where oid = 1184
211+instance HasOid 'PGdate where oid = 1082
212+instance HasOid 'PGtime where oid = 1083
213+instance HasOid 'PGtimetz where oid = 1266
214+instance HasOid 'PGinterval where oid = 1186
215+instance HasOid 'PGuuid where oid = 2950
216+instance HasOid 'PGinet where oid = 869
217+instance HasOid 'PGjson where oid = 114
218+instance HasOid 'PGjsonb where oid = 3802
219+
151220-- | `NullityType` encodes the potential presence or definite absence of a
152221-- @NULL@ allowing operations which are sensitive to such to be well typed.
153222--
@@ -166,6 +235,11 @@ data NullityType
166235type (:=>) constraint ty = '(constraint,ty)
167236infixr 7 :=>
168237
238+-- | The alias operator `:::` is like a promoted version of `As`,
239+-- a type level pair between an alias and some type.
240+type (:::) (alias :: Symbol) ty = '(alias,ty)
241+infixr 6 :::
242+
169243-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.
170244-- A column can be assigned a default value.
171245-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also
@@ -207,14 +281,11 @@ data TableConstraint
207281 | PrimaryKey [Symbol]
208282 | ForeignKey [Symbol] Symbol [Symbol]
209283
210−{- | A `TableConstraints` is a row of `TableConstraint`s.
211−
212−>>> :{
213−type family UsersConstraints :: TableConstraints where
214− UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]
215−:}
216−-}
284+-- | A `TableConstraints` is a row of `TableConstraint`s.
217285type TableConstraints = [(Symbol,TableConstraint)]
286+-- | A monokinded empty `TableConstraints`.
287+type family NilTableConstraints :: TableConstraints where
288+ NilTableConstraints = '[]
218289
219290-- | A `ForeignKey` must reference columns that either are
220291-- a `PrimaryKey` or form a `Unique` constraint.
@@ -238,64 +309,278 @@ type family Uniquely
238309-- :}
239310type TableType = (TableConstraints,ColumnsType)
240311
241−{- | A `RowType` is a row of `NullityType`. They correspond to Haskell
242−record types by means of `Squeal.PostgreSQL.Binary.RowPG` and are used in many places.
243−
244−>>> :{
245−type family PersonRow :: RowType where
246− PersonRow =
247− '[ "name" ::: 'NotNull 'PGtext
248− , "age" ::: 'NotNull 'PGint4
249− , "dateOfBirth" ::: 'Null 'PGdate
250− ]
251−:}
252−-}
253−type RowType = [(Symbol,NullityType)]
312+-- | `RelationType` is a row of `NullityType`
313+--
314+-- >>> :{
315+-- type family PersonRelation :: RelationType where
316+-- PersonRelation =
317+-- '[ "name" ::: 'NotNull 'PGtext
318+-- , "age" ::: 'NotNull 'PGint4
319+-- , "dateOfBirth" ::: 'Null 'PGdate
320+-- ]
321+-- :}
322+type RelationType = [(Symbol,NullityType)]
323+-- | A monokinded empty `RelationType`.
324+type family NilRelation :: RelationType where NilRelation = '[]
254325
255−{- | `FromType` is a row of `RowType`s. It can be thought of as
256−a product, or horizontal gluing and is used in `Squeal.PostgreSQL.Query.FromClause`s
257−and `Squeal.PostgreSQL.Query.TableExpression`s.
258−-}
259−type FromType = [(Symbol,RowType)]
260−
261−-- | `ColumnsToRow` removes column constraints.
262−type family ColumnsToRow (columns :: ColumnsType) :: RowType where
263− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': column5 ::: _ :=> ty5 ': columns) =
264− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': ColumnsToRow columns
265− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': 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 '[] = '[]
326+-- | `RelationsType` is a row of `RelationType`s, thought of as a product.
327+type RelationsType = [(Symbol,RelationType)]
328+
329+-- | `ColumnsToRelation` removes column constraints.
330+type family ColumnsToRelation (columns :: ColumnsType) :: RelationType where
331+ ColumnsToRelation '[] = '[]
332+ ColumnsToRelation (column ::: constraint :=> ty ': columns) =
333+ column ::: ty ': ColumnsToRelation columns
276334
277335-- | `TableToColumns` removes table constraints.
278336type family TableToColumns (table :: TableType) :: ColumnsType where
279337 TableToColumns (constraints :=> columns) = columns
280338
281−-- | Convert a table to a row type.
282−type family TableToRow (table :: TableType) :: RowType where
283− TableToRow tab = ColumnsToRow (TableToColumns tab)
339+-- | Convert a table to a relation.
340+type family TableToRelation (table :: TableType) :: RelationType where
341+ TableToRelation tab = ColumnsToRelation (TableToColumns tab)
284342
285−-- | Numeric Postgres types.
286−type PGNum =
287− '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]
343+-- | `Grouping` is an auxiliary namespace, created by
344+-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used
345+-- for typesafe aggregation
346+data Grouping
347+ = Ungrouped -- ^ no aggregation permitted
348+ | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped
288349
289−-- | Floating Postgres types.
290−type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]
291−
292−-- | Integral Postgres types.
293−type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]
350+{- | A `GroupedBy` constraint indicates that a table qualified column is
351+a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,
352+may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.
353+-}
354+class (KnownSymbol relation, KnownSymbol column)
355+ => GroupedBy relation column bys where
356+instance {-# OVERLAPPING #-} (KnownSymbol relation, KnownSymbol column)
357+ => GroupedBy relation column ('(table,column) ': bys)
358+instance {-# OVERLAPPABLE #-}
359+ ( KnownSymbol relation
360+ , KnownSymbol column
361+ , GroupedBy relation column bys
362+ ) => GroupedBy relation column (tabcol ': bys)
363+
364+-- | `Alias`es are proxies for a type level string or `Symbol`
365+-- and have an `IsLabel` instance so that with @-XOverloadedLabels@
366+--
367+-- >>> :set -XOverloadedLabels
368+-- >>> #foobar :: Alias "foobar"
369+-- Alias
370+data Alias (alias :: Symbol) = Alias
371+ deriving (Eq,GHC.Generic,Ord,Show,NFData)
372+instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where
373+ fromLabel = Alias
374+instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where
375+ fromLabel = fromLabel :* Nil
376+instance KnownSymbol alias => RenderSQL (Alias alias) where renderSQL = renderAlias
377+
378+-- | >>> renderAlias #jimbob
379+-- "\"jimbob\""
380+renderAlias :: KnownSymbol alias => Alias alias -> ByteString
381+renderAlias = doubleQuoted . fromString . symbolVal
382+
383+-- | >>> renderAliasString #ohmahgerd
384+-- "'ohmahgerd'"
385+renderAliasString :: KnownSymbol alias => Alias alias -> ByteString
386+renderAliasString = singleQuotedText . fromString . symbolVal
387+
388+-- | >>> import Generics.SOP (NP(..))
389+-- >>> renderAliases (#jimbob :* #kandi)
390+-- ["\"jimbob\"","\"kandi\""]
391+renderAliases
392+ :: All KnownSymbol aliases => NP Alias aliases -> [ByteString]
393+renderAliases = hcollapse
394+ . hcmap (Proxy @KnownSymbol) (K . renderAlias)
395+
396+-- | The `As` operator is used to name an expression. `As` is like a demoted
397+-- version of `:::`.
398+--
399+-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)
400+-- As (Just "hello") Alias
401+data Aliased expression aliased where
402+ As
403+ :: KnownSymbol alias
404+ => expression ty
405+ -> Alias alias
406+ -> Aliased expression (alias ::: ty)
407+deriving instance Show (expression ty)
408+ => Show (Aliased expression (alias ::: ty))
409+deriving instance Eq (expression ty)
410+ => Eq (Aliased expression (alias ::: ty))
411+deriving instance Ord (expression ty)
412+ => Ord (Aliased expression (alias ::: ty))
413+instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)
414+ => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where
415+ fromLabel = fromLabel @alias2 `As` fromLabel @alias1
416+
417+-- | The `Aliasable` class provides a way to scrap your `Nil`s
418+-- in an `NP` list of `Aliased` expressions.
419+class KnownSymbol alias => Aliasable alias expression aliased
420+ | aliased -> expression
421+ , aliased -> alias
422+ where as :: expression -> Alias alias -> aliased
423+instance (alias ~ alias1, KnownSymbol alias) => Aliasable alias
424+ (expression ty)
425+ (Aliased expression (alias1 ::: ty))
426+ where
427+ as = As
428+instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias
429+ (expression ty)
430+ (NP (Aliased expression) tys)
431+ where
432+ expression `as` alias = expression `As` alias :* Nil
433+
434+-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")
435+-- >>> renderAliasedAs renderMaybe (Just (3::Int) `As` #an_int)
436+-- "Just AS \"an_int\""
437+renderAliasedAs
438+ :: (forall ty. expression ty -> ByteString)
439+ -> Aliased expression aliased
440+ -> ByteString
441+renderAliasedAs render (expression `As` alias) =
442+ render expression <> " AS " <> renderAlias alias
443+
444+-- | `AliasesOf` retains the AliasesOf in a row.
445+type family AliasesOf aliaseds where
446+ AliasesOf '[] = '[]
447+ AliasesOf (alias ::: ty ': tys) = alias ': AliasesOf tys
448+
449+-- | The `ZipAliased` class provides a type family for zipping
450+-- `Symbol` lists together with arbitrary lists of the same size,
451+-- with an associated type family `ZipAs`, together with
452+-- a method `zipAs` for zipping heterogeneous lists of `Alias`es
453+-- together with a heterogeneous list of expressions into
454+-- a heterogeneous list of `Aliased` expressions.
455+class
456+ ( SListI (ZipAs ns xs)
457+ , All KnownSymbol ns
458+ ) => ZipAliased ns xs where
459+
460+ type family ZipAs
461+ (ns :: [Symbol]) (xs :: [k]) = (zs :: [(Symbol,k)]) | zs -> ns xs
462+
463+ zipAs
464+ :: NP Alias ns
465+ -> NP expr xs
466+ -> NP (Aliased expr) (ZipAs ns xs)
467+
468+instance ZipAliased '[] '[] where
469+ type ZipAs '[] '[] = '[]
470+ zipAs Nil Nil = Nil
471+
472+instance
473+ ( KnownSymbol n
474+ , ZipAliased ns xs
475+ ) => ZipAliased (n ': ns) (x ': xs) where
476+ type ZipAs (n ': ns) (x ': xs) = '(n,x) ': ZipAs ns xs
477+ zipAs (n :* ns) (x :* xs) = x `As` n :* zipAs ns xs
478+
479+-- | @HasUnique alias fields field@ is a constraint that proves that
480+-- @fields@ is a singleton of @alias ::: field@.
481+type HasUnique alias fields field = fields ~ '[alias ::: field]
482+
483+-- | @Has alias fields field@ is a constraint that proves that
484+-- @fields@ has a field of @alias ::: field@, inferring @field@
485+-- from @alias@ and @fields@.
486+class KnownSymbol alias =>
487+ Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)
488+ | alias fields -> field where
489+instance {-# OVERLAPPING #-} KnownSymbol alias
490+ => Has alias (alias ::: field ': fields) field
491+instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)
492+ => Has alias (field' ': fields) field
493+
494+-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer
495+-- a list of @subfields@.
496+class
497+ ( All KnownSymbol aliases
498+ ) => HasAll
499+ (aliases :: [Symbol])
500+ (fields :: [(Symbol,kind)])
501+ (subfields :: [(Symbol,kind)])
502+ | aliases fields -> subfields where
503+instance {-# OVERLAPPING #-} HasAll '[] fields '[]
504+instance {-# OVERLAPPABLE #-}
505+ (Has alias fields field, HasAll aliases fields subfields)
506+ => HasAll (alias ': aliases) fields (alias ::: field ': subfields)
507+
508+-- | Analagous to `IsLabel`, the constraint
509+-- `IsQualified` defines `!` for a column alias qualified
510+-- by a table alias.
511+class IsQualified table column expression where
512+ (!) :: Alias table -> Alias column -> expression
513+ infixl 9 !
514+instance IsQualified table column (Alias table, Alias column) where (!) = (,)
515+
516+-- | @Elem@ is a promoted `Data.List.elem`.
517+type family Elem x xs where
518+ Elem x '[] = 'False
519+ Elem x (x ': xs) = 'True
520+ Elem x (_ ': xs) = Elem x xs
521+
522+-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.
523+type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True
524+
525+-- | `PGNum` is a constraint on `PGType` whose
526+-- `Squeal.PostgreSQL.Expression.Expression`s have a `Num` constraint.
527+type PGNum ty =
528+ In ty '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]
529+
530+-- | `PGFloating` is a constraint on `PGType` whose
531+-- `Squeal.PostgreSQL.Expression.Expression`s
532+-- have `Fractional` and `Floating` constraints.
533+type PGFloating ty = In ty '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]
534+
535+-- | `PGIntegral` is a constraint on `PGType` whose
536+-- `Squeal.PostgreSQL.Expression.Expression`s
537+-- have `Squeal.PostgreSQL.Expression.div_` and
538+-- `Squeal.PostgreSQL.Expression.mod_` functions.
539+type PGIntegral ty = In ty '[ 'PGint2, 'PGint4, 'PGint8]
540+
541+-- | Error message helper for displaying unavailable\/unknown\/placeholder type
542+-- variables whose kind is known.
543+type Placeholder k = 'Text "(_::" :<>: 'ShowType k :<>: 'Text ")"
544+
545+type ErrArrayOf arr ty = arr :<>: 'Text " " :<>: ty
546+type ErrPGfixarrayOf t = ErrArrayOf ('ShowType 'PGfixarray :<>: 'Text " " :<>: Placeholder Nat) t
547+type ErrPGvararrayOf t = ErrArrayOf ('ShowType 'PGvararray) t
548+
549+-- | Ensure a type is a valid array type.
550+type family PGarray name arr :: Constraint where
551+ PGarray name ('PGvararray x) = ()
552+ PGarray name ('PGfixarray n x) = ()
553+ PGarray name val = TypeError
554+ ('Text name :<>: 'Text ": Unsatisfied PGarray constraint. Expected either: "
555+ :$$: 'Text " • " :<>: ErrPGvararrayOf (Placeholder PGType)
556+ :$$: 'Text " • " :<>: ErrPGfixarrayOf (Placeholder PGType)
557+ :$$: 'Text "But got: " :<>: 'ShowType val)
558+
559+-- | Ensure a type is a valid array type with a specific element type.
560+type family PGarrayOf name arr ty :: Constraint where
561+ PGarrayOf name ('PGvararray x) ty = x ~ ty
562+ PGarrayOf name ('PGfixarray n x) ty = x ~ ty
563+ PGarrayOf name val ty = TypeError
564+ ( 'Text name :<>: 'Text "Unsatisfied PGarrayOf constraint. Expected either: "
565+ :$$: 'Text " • " :<>: ErrPGvararrayOf ( 'ShowType ty )
566+ :$$: 'Text " • " :<>: ErrPGfixarrayOf ( 'ShowType ty )
567+ :$$: 'Text "But got: " :<>: 'ShowType val)
568+
569+-- | Ensure a type is a valid array type whose elements are text.
570+type PGtextArray name arr = PGarrayOf name arr 'PGtext
294571
295572-- | `PGTypeOf` forgets about @NULL@ and any column constraints.
296573type family PGTypeOf (ty :: NullityType) :: PGType where
297574 PGTypeOf (nullity pg) = pg
298575
576+-- | `SameTypes` is a constraint that proves two `ColumnsType`s have the same
577+-- length and the same `ColumnType`s.
578+type family SameTypes (columns0 :: ColumnsType) (columns1 :: ColumnsType)
579+ :: Constraint where
580+ SameTypes '[] '[] = ()
581+ SameTypes (column0 ::: def0 :=> ty0 ': columns0) (column1 ::: def1 :=> ty1 ': columns1)
582+ = (ty0 ~ ty1, SameTypes columns0 columns1)
583+
299584-- | Equality constraint on the underlying `PGType` of two columns.
300585class SamePGType
301586 (ty0 :: (Symbol,ColumnType)) (ty1 :: (Symbol,ColumnType)) where
@@ -305,63 +590,49 @@ instance ty0 ~ ty1 => SamePGType
305590
306591-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.
307592type 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
314593 AllNotNull '[] = ()
594+ AllNotNull (column ::: def :=> 'NotNull ty ': columns) = AllNotNull columns
315595
316596-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some
317597-- @NOT NULL@.
318598type family NotAllNull (columns :: ColumnsType) :: Constraint where
319− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
320− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
321− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
322− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
323− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
324− NotAllNull (_ ::: _ :=> 'NotNull _ ': _) = ()
325− NotAllNull (_ ::: _ :=> 'Null _ ': columns) = NotAllNull columns
326−
327−-- | `NullifyType` is an idempotent that nullifies a `NullityType`.
599+ NotAllNull (column ::: def :=> 'NotNull ty ': columns) = ()
600+ NotAllNull (column ::: def :=> 'Null ty ': columns) = NotAllNull columns
601+
602+-- | `NullifyType` is an idempotent that nullifies a `ColumnType`.
328603type family NullifyType (ty :: NullityType) :: NullityType where
329604 NullifyType ('Null ty) = 'Null ty
330605 NullifyType ('NotNull ty) = 'Null ty
331606
332−-- | `NullifyRow` is an idempotent that nullifies a `RowType`.
333−type family NullifyRow (columns :: RowType) :: RowType where
334− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': columns) =
335− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': column5 ::: NullifyType ty5 ': NullifyRow columns
336− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': columns) =
337− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': NullifyRow columns
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`
607+-- | `NullifyRelation` is an idempotent that nullifies a `ColumnsType`.
608+type family NullifyRelation (columns :: RelationType) :: RelationType where
609+ NullifyRelation '[] = '[]
610+ NullifyRelation (column ::: ty ': columns) =
611+ column ::: NullifyType ty ': NullifyRelation columns
612+
613+-- | `NullifyRelations` is an idempotent that nullifies a `RelationsType`
349614-- used to nullify the left or right hand side of an outer join
350615-- in a `Squeal.PostgreSQL.Query.FromClause`.
351−type family NullifyFrom (tables :: FromType) :: FromType where
352− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': table5 ::: columns5 ': tables) =
353− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns5 ': table5 ::: NullifyRow columns4 ': NullifyFrom tables
354− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': tables) =
355− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns4 ': NullifyFrom tables
356− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': tables) =
357− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': NullifyFrom tables
358− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': tables) =
359− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': NullifyFrom tables
360− NullifyFrom (table ::: columns ': table1 ::: columns1 ': tables) =
361− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': NullifyFrom tables
362− NullifyFrom (table ::: columns ': tables) =
363− table ::: NullifyRow columns ': NullifyFrom tables
364− NullifyFrom '[] = '[]
616+type family NullifyRelations (tables :: RelationsType) :: RelationsType where
617+ NullifyRelations '[] = '[]
618+ NullifyRelations (table ::: columns ': tables) =
619+ table ::: NullifyRelation columns ': NullifyRelations tables
620+
621+-- | `RelationToRowType` drops the nullity constraints of its argument relations.
622+type family RelationToRowType (tables :: RelationType) :: [(Symbol, PGType)] where
623+ RelationToRowType (nullity x : xs) = x : RelationToRowType xs
624+ RelationToRowType '[] = '[]
625+
626+-- | `RelationToNullityTypes` drops the column constraints.
627+type family RelationToNullityTypes (rel :: RelationType) :: [NullityType] where
628+ RelationToNullityTypes ('(k, x) : xs) = x : RelationToNullityTypes xs
629+ RelationToNullityTypes '[] = '[]
630+
631+-- | `Join` is simply promoted `++` and is used in @JOIN@s in
632+-- `Squeal.PostgreSQL.Query.FromClause`s.
633+type family Join xs ys where
634+ Join '[] ys = ys
635+ Join (x ': xs) ys = x ': Join xs ys
365636
366637-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in
367638-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@
@@ -371,100 +642,62 @@ type family Create alias x xs where
371642 Create alias x (alias ::: y ': xs) = TypeError
372643 ('Text "Create: alias "
373644 ':<>: 'ShowType alias
374− ':<>: 'Text "already exists")
645+ ':<>: 'Text "already in use")
375646 Create alias y (x ': xs) = x ': Create alias y xs
376647
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−
394648-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@
395649-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements
396650-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.
397651type 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
652+ Drop alias ((alias ::: x) ': xs) = xs
403653 Drop alias (x ': xs) = x ': Drop alias xs
404654
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−
437655-- | @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`
656+-- with the type `x` and is used in `Squeal.PostgreSQL.Definition.alterTable`
439657-- and `Squeal.PostgreSQL.Definition.alterColumn`.
440658type family Alter alias x xs where
441− Alter alias x '[] = TypeError
442− ('Text "Alter: alias "
443− ':<>: 'ShowType alias
444− ':<>: 'Text " does not exist" )
445659 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
446660 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs
447661
448−type family AlterIfExists alias x xs where
449− AlterIfExists alias x '[] = '[]
450− AlterIfExists alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
451− AlterIfExists alias x1 (x0 ': xs) = x0 ': AlterIfExists alias x1 xs
662+-- type family AddConstraint constraint ty where
663+-- AddConstraint constraint (constraints :=> ty)
664+-- = AsSet (constraint ': constraints) :=> ty
665+
666+-- type family DeleteFromList (e :: elem) (list :: [elem]) where
667+-- DeleteFromList elem '[] = '[]
668+-- DeleteFromList elem (x ': xs) =
669+-- If (Cmp elem x == 'EQ) xs (x ': DeleteFromList elem xs)
670+
671+-- type family DropConstraint constraint ty where
672+-- DropConstraint constraint (constraints :=> ty)
673+-- = (AsSet (DeleteFromList constraint constraints)) :=> ty
452674
453675-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@
454676-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and
455677-- `Squeal.PostgreSQL.Definition.renameColumn`.
456678type family Rename alias0 alias1 xs where
457− Rename alias0 alias1 '[] = TypeError
458− ('Text "Rename: alias "
459− ':<>: 'ShowType alias0
460− ':<>: 'Text " does not exist" )
461679 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
462680 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs
463681
464−type family RenameIfExists alias0 alias1 xs where
465− RenameIfExists alias x '[] = '[]
466− RenameIfExists alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
467− RenameIfExists alias0 alias1 (x ': xs) = x ': RenameIfExists alias0 alias1 xs
682+-- | `MapMaybes` is used in the binary instances of composite types.
683+class MapMaybes xs where
684+ type family Maybes (xs :: [Type]) = (mxs :: [Type]) | mxs -> xs
685+ maybes :: NP Maybe xs -> NP I (Maybes xs)
686+ unMaybes :: NP I (Maybes xs) -> NP Maybe xs
687+instance MapMaybes '[] where
688+ type Maybes '[] = '[]
689+ maybes Nil = Nil
690+ unMaybes Nil = Nil
691+instance MapMaybes xs => MapMaybes (x ': xs) where
692+ type Maybes (x ': xs) = Maybe x ': Maybes xs
693+ maybes (x :* xs) = I x :* maybes xs
694+ unMaybes (I mx :* xs) = mx :* unMaybes xs
695+
696+-- | `Nulls` is used to construct a `Squeal.Postgresql.Expression.row`
697+-- of a composite type.
698+type family Nulls tys where
699+ Nulls '[] = '[]
700+ Nulls (field ::: ty ': tys) = field ::: 'Null ty ': Nulls tys
468701
469702-- | Check if a `TableConstraint` involves a column
470703type family ConstraintInvolves column constraint where
@@ -486,76 +719,21 @@ type family DropIfConstraintsInvolve column constraints where
486719-- `View` or `Typedef`.
487720data SchemumType
488721 = Table TableType
489− | View RowType
722+ | View RelationType
490723 | 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.
546724
547−There are several reasons why one might want to use schemas:
548−
549− * To allow many users to use one database without interfering with each other.
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)]
725+-- | The schema of a database consists of a list of aliased,
726+-- user-defined `SchemumType`s.
727+type SchemaType = [(Symbol,SchemumType)]
555728
556−-- | A type family to use for a single schema database.
557−type family Public (schema :: SchemaType) :: SchemasType
558− where Public schema = '["public" ::: schema]
729+-- | Used in `Squeal.Postgresql.Manipulation.with`.
730+type family With
731+ (relations :: RelationsType)
732+ (schema :: SchemaType)
733+ :: SchemaType where
734+ With '[] schema = schema
735+ With (alias ::: rel ': rels) schema =
736+ alias ::: 'View rel ': With rels schema
559737
560738-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas
561739-- the overloaded label, `fromLabel` is used for column references,
@@ -568,29 +746,176 @@ instance labels ~ '[label]
568746 => IsPGlabel label (NP PGlabel labels) where label = PGlabel :* Nil
569747-- | A `PGlabel` unit type with an `IsPGlabel` instance
570748data PGlabel (label :: Symbol) = PGlabel
571−instance KnownSymbol label => RenderSQL (PGlabel label) where
572− renderSQL _ = "\'" <> renderSymbol @label <> "\'"
573−instance All KnownSymbol labels => RenderSQL (NP PGlabel labels) where
574− renderSQL
575− = commaSeparated
576− . hcollapse
577− . hcmap (Proxy @KnownSymbol) (K . renderSQL)
749+-- | Renders a label
750+renderLabel :: KnownSymbol label => proxy label -> ByteString
751+renderLabel (_ :: proxy label) =
752+ "\'" <> fromString (symbolVal (Proxy @label)) <> "\'"
753+-- | Renders a list of labels
754+renderLabels
755+ :: All KnownSymbol labels => NP PGlabel labels -> [ByteString]
756+renderLabels = hcollapse
757+ . hcmap (Proxy @KnownSymbol) (K . renderLabel)
758+
759+-- | The `PG` type family embeds a subset of Haskell types
760+-- as Postgres basic types.
761+--
762+-- >>> :kind! PG LocalTime
763+-- PG LocalTime :: PGType
764+-- = 'PGtimestamp
765+type family PG (hask :: Type) :: PGType where
766+ PG Bool = 'PGbool
767+ PG Int16 = 'PGint2
768+ PG Int32 = 'PGint4
769+ PG Int64 = 'PGint8
770+ PG Word16 = 'PGint2
771+ PG Word32 = 'PGint4
772+ PG Word64 = 'PGint8
773+ PG Scientific = 'PGnumeric
774+ PG Float = 'PGfloat4
775+ PG Double = 'PGfloat8
776+ PG Char = 'PGchar 1
777+ PG Text = 'PGtext
778+ PG Lazy.Text = 'PGtext
779+ PG ByteString = 'PGbytea
780+ PG Lazy.ByteString = 'PGbytea
781+ PG LocalTime = 'PGtimestamp
782+ PG UTCTime = 'PGtimestamptz
783+ PG Day = 'PGdate
784+ PG TimeOfDay = 'PGtime
785+ PG (TimeOfDay, TimeZone) = 'PGtimetz
786+ PG DiffTime = 'PGinterval
787+ PG UUID = 'PGuuid
788+ PG (NetAddr IP) = 'PGinet
789+ PG Value = 'PGjson
790+ PG ty = TypeError
791+ ('Text "There is no Postgres basic type for " ':<>: 'ShowType ty)
792+
793+-- | The `EnumFrom` type family embeds Haskell enum types, ADTs with
794+-- nullary constructors, as Postgres enum types
795+--
796+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
797+-- >>> instance Generic Schwarma
798+-- >>> instance HasDatatypeInfo Schwarma
799+-- >>> :kind! EnumFrom Schwarma
800+-- EnumFrom Schwarma :: PGType
801+-- = 'PGenum '["Beef", "Lamb", "Chicken"]
802+type family EnumFrom (hask :: Type) :: PGType where
803+ EnumFrom hask = 'PGenum (LabelsFrom hask)
804+
805+-- | The `LabelsFrom` type family calculates the constructors of a
806+-- Haskell enum type.
807+--
808+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
809+-- >>> instance Generic Schwarma
810+-- >>> instance HasDatatypeInfo Schwarma
811+-- >>> :kind! LabelsFrom Schwarma
812+-- LabelsFrom Schwarma :: [Type.ConstructorName]
813+-- = '["Beef", "Lamb", "Chicken"]
814+type family LabelsFrom (hask :: Type) :: [Type.ConstructorName] where
815+ LabelsFrom hask =
816+ ConstructorNamesOf (ConstructorsOf (DatatypeInfoOf hask))
817+
818+-- | The `CompositeFrom` type family embeds Haskell record types as
819+-- Postgres composite types, as long as the record fields
820+-- are `Maybe`s of Haskell types that can be embedded as basic types
821+-- with the `PG` type family.
822+--
823+-- >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
824+-- >>> instance Generic Row
825+-- >>> instance HasDatatypeInfo Row
826+-- >>> :kind! CompositeFrom Row
827+-- CompositeFrom Row :: PGType
828+-- = 'PGcomposite '['("a", 'PGint2), '("b", 'PGtimestamp)]
829+type family CompositeFrom (hask :: Type) :: PGType where
830+ CompositeFrom hask =
831+ 'PGcomposite (ZipAs (FieldNamesFrom hask) (FieldTypesFrom hask))
832+
833+-- | >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
834+-- >>> instance Generic Row
835+-- >>> instance HasDatatypeInfo Row
836+-- >>> :kind! FieldNamesFrom Row
837+-- FieldNamesFrom Row :: [Type.FieldName]
838+-- = '["a", "b"]
839+type family FieldNamesFrom (hask :: Type) :: [Type.FieldName] where
840+ FieldNamesFrom hask = FieldNamesOf (FieldsOf (DatatypeInfoOf hask))
841+
842+-- | >>> data Row = Row { a :: Maybe Int16, b :: Maybe LocalTime } deriving GHC.Generic
843+-- >>> instance Generic Row
844+-- >>> instance HasDatatypeInfo Row
845+-- >>> :kind! FieldTypesFrom Row
846+-- FieldTypesFrom Row :: [PGType]
847+-- = '['PGint2, 'PGtimestamp]
848+type family FieldTypesFrom (hask :: Type) :: [PGType] where
849+ FieldTypesFrom hask = FieldTypesOf (RecordCodeOf hask (Code hask))
850+
851+-- | Calculates constructors of a datatype.
852+type family ConstructorsOf (datatype :: Type.DatatypeInfo)
853+ :: [Type.ConstructorInfo] where
854+ ConstructorsOf ('Type.ADT _module _datatype constructors) =
855+ constructors
856+ ConstructorsOf ('Type.Newtype _module _datatype constructor) =
857+ '[constructor]
858+
859+-- | Calculates the name of a nullary constructor, otherwise
860+-- generates a type error.
861+type family ConstructorNameOf (constructors :: Type.ConstructorInfo)
862+ :: Type.ConstructorName where
863+ ConstructorNameOf ('Type.Constructor name) = name
864+ ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError
865+ ('Text "ConstructorNameOf error: non-nullary constructor "
866+ ':<>: 'Text name)
867+ ConstructorNameOf ('Type.Record name _fields) = TypeError
868+ ('Text "ConstructorNameOf error: non-nullary constructor "
869+ ':<>: 'Text name)
870+
871+-- | Calculate the names of nullary constructors.
872+type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])
873+ :: [Type.ConstructorName] where
874+ ConstructorNamesOf '[] = '[]
875+ ConstructorNamesOf (constructor ': constructors) =
876+ ConstructorNameOf constructor ': ConstructorNamesOf constructors
877+
878+-- | Calculate the fields of a datatype.
879+type family FieldsOf (datatype :: Type.DatatypeInfo)
880+ :: [Type.FieldInfo] where
881+ FieldsOf ('Type.ADT _module _datatype '[ 'Type.Record _name fields]) =
882+ fields
883+ FieldsOf ('Type.Newtype _module _datatype ('Type.Record _name fields)) =
884+ fields
885+
886+-- | Calculate the name of a field.
887+type family FieldNameOf (field :: Type.FieldInfo) :: Type.FieldName where
888+ FieldNameOf ('Type.FieldInfo name) = name
889+
890+-- | Calculate the names of fields.
891+type family FieldNamesOf (fields :: [Type.FieldInfo])
892+ :: [Type.FieldName] where
893+ FieldNamesOf '[] = '[]
894+ FieldNamesOf (field ': fields) = FieldNameOf field ': FieldNamesOf fields
895+
896+-- | >>> :kind! FieldTypeOf (Maybe Int16)
897+-- FieldTypeOf (Maybe Int16) :: PGType
898+-- = 'PGint2
899+type family FieldTypeOf (maybe :: Type) where
900+ FieldTypeOf (Maybe hask) = PG hask
901+ FieldTypeOf ty = TypeError
902+ ('Text "FieldTypeOf error: non-Maybe type " ':<>: 'ShowType ty)
903+
904+-- | Calculate the types of fields.
905+type family FieldTypesOf (fields :: [Type]) where
906+ FieldTypesOf '[] = '[]
907+ FieldTypesOf (field ': fields) = FieldTypeOf field ': FieldTypesOf fields
908+
909+-- | Inspect the code of an algebraic datatype and ensure it's a product,
910+-- otherwise generate a type error
911+type family RecordCodeOf (hask :: Type) (code ::[[Type]]) :: [Type] where
912+ RecordCodeOf _hask '[tys] = tys
913+ RecordCodeOf hask _tys = TypeError
914+ ('Text "RecordCodeOf error: non-Record type " ':<>: 'ShowType hask)
578915
579916-- | Is a type a valid JSON key?
580−type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]
917+type PGjsonKey key = key `In` '[ 'PGint2, 'PGint4, 'PGtext ]
581918
582919-- | Is a type a valid JSON type?
583−type PGJsonType = '[ 'PGjson, 'PGjsonb ]
584−
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
920+type PGjson_ json = json `In` '[ 'PGjson, 'PGjsonb ]
921+
squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+74−101
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL.Transaction
33Description: Squeal transaction control language
4−Copyright: (c) Eitan Chatav, 2019
4+Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -9,125 +9,98 @@ Squeal transaction control language.
99-}
1010
1111{-# LANGUAGE
12− DataKinds
13− , FlexibleContexts
12+ FlexibleContexts
1413 , LambdaCase
1514 , OverloadedStrings
16− , TypeInType
1715#-}
1816
1917module Squeal.PostgreSQL.Transaction
2018 ( -- * Transaction
2119 transactionally
2220 , transactionally_
23− , transactionallyRetry
24− , ephemerally
25− , ephemerally_
2621 , begin
2722 , commit
2823 , rollback
24+ , transactionallySchema
25+ , transactionallySchema_
2926 -- * Transaction Mode
3027 , TransactionMode (..)
3128 , defaultMode
3229 , longRunningMode
3330 , IsolationLevel (..)
31+ , renderIsolationLevel
3432 , AccessMode (..)
33+ , renderAccessMode
3534 , DeferrableMode (..)
35+ , renderDeferrableMode
3636 ) where
3737
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
3946
4047import Squeal.PostgreSQL.Manipulation
4148import Squeal.PostgreSQL.Render
4249import Squeal.PostgreSQL.PQ
50+import Squeal.PostgreSQL.Schema
4351
44−{- | Run a 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−-}
52+-- | Run a schema invariant computation `transactionally`.
5053transactionally
51− :: (MonadUnliftIO tx, MonadPQ schemas tx)
54+ :: (MonadBaseControl IO tx, MonadPQ schema tx)
5255 => TransactionMode
5356 -> tx x -- ^ run inside a transaction
5457 -> tx x
5558transactionally mode tx = mask $ \restore -> do
56− manipulate_ $ begin mode
57− result <- restore tx `onException` (manipulate_ rollback)
58− manipulate_ commit
59+ _ <- begin mode
60+ result <- restore tx `onException` rollback
61+ _ <- commit
5962 return result
6063
61−-- | Run a computation `transactionally_`, in `defaultMode`.
64+-- | Run a schema invariant computation `transactionally_` in `defaultMode`.
6265transactionally_
63− :: (MonadUnliftIO tx, MonadPQ schemas tx)
66+ :: (MonadBaseControl IO tx, MonadPQ schema tx)
6467 => tx x -- ^ run inside a transaction
6568 -> tx x
6669transactionally_ = transactionally defaultMode
6770
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−
12071-- | @BEGIN@ a transaction.
121−begin :: TransactionMode -> Manipulation_ schemas () ()
122−begin mode = UnsafeManipulation $ "BEGIN" <+> renderSQL mode
72+begin :: MonadPQ schema tx => TransactionMode -> tx (K Result NilRelation)
73+begin mode = manipulate . UnsafeManipulation $
74+ "BEGIN" <+> renderTransactionMode mode <> ";"
12375
124−-- | @COMMIT@ a transaction.
125−commit :: Manipulation_ schemas () ()
126−commit = UnsafeManipulation "COMMIT"
76+-- | @COMMIT@ a schema invariant transaction.
77+commit :: MonadPQ schema tx => tx (K Result NilRelation)
78+commit = manipulate $ UnsafeManipulation "COMMIT;"
12779
128−-- | @ROLLBACK@ a transaction.
129−rollback :: Manipulation_ schemas () ()
130−rollback = UnsafeManipulation "ROLLBACK"
80+-- | @ROLLBACK@ a schema invariant transaction.
81+rollback :: MonadPQ schema tx => tx (K Result NilRelation)
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
131104
132105-- | The available transaction characteristics are the transaction `IsolationLevel`,
133106-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.
@@ -140,7 +113,7 @@ data TransactionMode = TransactionMode
140113-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
141114-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.
142115defaultMode :: TransactionMode
143−defaultMode = TransactionMode ReadCommitted ReadWrite NotDeferrable
116+defaultMode = TransactionMode Serializable ReadWrite NotDeferrable
144117
145118-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
146119-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.
@@ -149,12 +122,12 @@ longRunningMode :: TransactionMode
149122longRunningMode = TransactionMode Serializable ReadOnly Deferrable
150123
151124-- | Render a `TransactionMode`.
152−instance RenderSQL TransactionMode where
153− renderSQL mode =
154− "ISOLATION LEVEL"
155− <+> renderSQL (isolationLevel mode)
156− <+> renderSQL (accessMode mode)
157− <+> renderSQL (deferrableMode mode)
125+renderTransactionMode :: TransactionMode -> ByteString
126+renderTransactionMode mode =
127+ "ISOLATION LEVEL"
128+ <+> renderIsolationLevel (isolationLevel mode)
129+ <+> renderAccessMode (accessMode mode)
130+ <+> renderDeferrableMode (deferrableMode mode)
158131
159132-- | The SQL standard defines four levels of transaction isolation.
160133-- The most strict is `Serializable`, which is defined by the standard in a paragraph
@@ -205,12 +178,12 @@ data IsolationLevel
205178 deriving (Show, Eq)
206179
207180-- | Render an `IsolationLevel`.
208−instance RenderSQL IsolationLevel where
209− renderSQL = \case
210− Serializable -> "SERIALIZABLE"
211− ReadCommitted -> "READ COMMITTED"
212− ReadUncommitted -> "READ UNCOMMITTED"
213− RepeatableRead -> "REPEATABLE READ"
181+renderIsolationLevel :: IsolationLevel -> ByteString
182+renderIsolationLevel = \case
183+ Serializable -> "SERIALIZABLE"
184+ ReadCommitted -> "READ COMMITTED"
185+ ReadUncommitted -> "READ UNCOMMITTED"
186+ RepeatableRead -> "REPEATABLE READ"
214187
215188-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.
216189-- `ReadWrite` is the default. When a transaction is `ReadOnly`,
@@ -227,10 +200,10 @@ data AccessMode
227200 deriving (Show, Eq)
228201
229202-- | Render an `AccessMode`.
230−instance RenderSQL AccessMode where
231− renderSQL = \case
232− ReadWrite -> "READ WRITE"
233− ReadOnly -> "READ ONLY"
203+renderAccessMode :: AccessMode -> ByteString
204+renderAccessMode = \case
205+ ReadWrite -> "READ WRITE"
206+ ReadOnly -> "READ ONLY"
234207
235208-- | The `Deferrable` transaction property has no effect
236209-- unless the transaction is also `Serializable` and `ReadOnly`.
@@ -246,7 +219,7 @@ data DeferrableMode
246219 deriving (Show, Eq)
247220
248221-- | Render a `DeferrableMode`.
249−instance RenderSQL DeferrableMode where
250− renderSQL = \case
251− Deferrable -> "DEFERRABLE"
252− NotDeferrable -> "NOT DEFERRABLE"
222+renderDeferrableMode :: DeferrableMode -> ByteString
223+renderDeferrableMode = \case
224+ Deferrable -> "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
22packages:
33- squeal-postgresql
4−
5−extra-deps:
6−- unliftio-pool-0.2.1.0
7−- github: morphismtech/free-categories
8− commit: c0e555fbefb5c21619e532264c4dfeac556d0630