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52 files changed+8632−5262
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unifiedsplit
.circleci/config.yml+1−1 README.md+64−75 RELEASE NOTES.md+400 squeal-postgresql/exe/Example.hs+15−13 squeal-postgresql/squeal-postgresql.cabal+58−16 squeal-postgresql/src/Squeal/PostgreSQL.hs+70−51 squeal-postgresql/src/Squeal/PostgreSQL/Alias.hs+249 squeal-postgresql/src/Squeal/PostgreSQL/Binary.hs+221−332 squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+15−1012 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+242−2196 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+170−177 squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+337−186 squeal-postgresql/src/Squeal/PostgreSQL/PG.hs+388 squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+138−103 squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+72−109 squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+311−414 squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+39−6 squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+181−371 squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+78−48 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-postgresql/test/Specs/ExceptionHandling.hs−126 squeal-postgresql/test/Specs/Specs.hs−7 stack.yaml+6−1
.circleci/config.yml+1−1
@@ -2,7 +2,7 @@ version: 2
22jobs:
33 build:
44 docker:
5− - image: haskell:8.6.3
5+ - image: haskell:8.6.5
66 - image: circleci/postgres:latest
77 environment:
88 POSTGRES_USER: root
README.md+64−75
@@ -46,7 +46,11 @@ composable and cover a large portion of SQL.
4646* transactions
4747* views
4848* array, composite and enumerated types
49−* json operations
49+* json functions and operations
50+* multischema support
51+* correlated subqueries
52+* window functions
53+* text search
5054
5155## installation
5256
@@ -72,19 +76,17 @@ First, we need some language extensions because Squeal uses modern GHC
7276features.
7377
7478```Haskell
75−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
76−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators
79+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
80+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
7781```
7882
7983We'll need some imports.
8084
8185```Haskell
82−>>> import Control.Monad (void)
83−>>> import Control.Monad.Base (liftBase)
86+>>> import Control.Monad.IO.Class (liftIO)
8487>>> import Data.Int (Int32)
8588>>> import Data.Text (Text)
8689>>> import Squeal.PostgreSQL
87−>>> import Squeal.PostgreSQL.Render
8890```
8991
9092We'll use generics to easily convert between Haskell and PostgreSQL values.
@@ -99,27 +101,27 @@ we use `DataKinds` and `TypeOperators`.
99101
100102```Haskell
101103>>> :{
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"] ]
102115type Schema =
103− '[ "users" ::: 'Table (
104− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
105− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
106− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
107− ])
108− , "emails" ::: 'Table (
109− '[ "pk_emails" ::: 'PrimaryKey '["id"]
110− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
111− ] :=>
112− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
113− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
114− , "email" ::: 'NoDef :=> 'Null 'PGtext
115− ])
116− ]
116+ '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)
117+ , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]
118+type Schemas = Public Schema
117119:}
118120```
119121
120122Notice the use of type operators.
121123
122−`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemumType`,
124+`:::` is used to pair an alias `Symbol` with a `SchemumType`,
123125a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's `::`
124126operator.
125127
@@ -128,7 +130,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
128130yielding a `ColumnType`. It is intended to connote Haskell's `=>` operator
129131
130132Next, we'll write `Definition`s to set up and tear down the schema. In
131−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
133+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
132134has two type parameters, corresponding to the schema
133135before being run and the schema after. We can compose definitions using `>>>`.
134136Here and in the rest of our commands we make use of overloaded
@@ -137,8 +139,8 @@ labels to refer to named tables and columns in our schema.
137139```Haskell
138140>>> :{
139141let
140− setup :: Definition '[] Schema
141− setup =
142+ setup :: Definition (Public '[]) Schemas
143+ setup =
142144 createTable #users
143145 ( serial `as` #id :*
144146 (text & notNullable) `as` #name )
@@ -169,7 +171,7 @@ primary and foreign keys, making them somewhat complex. Our `teardown`
169171```Haskell
170172>>> :{
171173let
172− teardown :: Definition Schema '[]
174+ teardown :: Definition Schemas (Public '[])
173175 teardown = dropTable #emails >>> dropTable #users
174176:}
175177
@@ -178,54 +180,54 @@ DROP TABLE "emails";
178180DROP TABLE "users";
179181```
180182
181−Next, we'll write `Manipulation`s to insert data into our two tables.
182−A `Manipulation` like `insertRow`, `update` or `deleteFrom`
183−has three type parameters, the schema it refers to, a list of parameters
184−it can take as input, and a list of columns it produces as output. When
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
185196we insert into the users table, we will need a parameter for the `name`
186197field but not for the `id` field. Since it's serial, we can use a default
187198value. However, since the emails table refers to the users table, we will
188199need to retrieve the user id that the insert generates and insert it into
189−the emails table. Take a careful look at the type and definition of both
190−of our inserts.
200+the emails table. We can do this in a single `Manipulation_` by using a
201+`with` statement.
191202
192203```Haskell
193204>>> :{
194205let
195− insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]
196− insertUser = insertRow #users
197− (Default `as` #id :* Set (param @1) `as` #name)
198− OnConflictDoNothing (Returning (#id `as` #fromOnly))
199−:}
200−
201−>>> :{
202−let
203− insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]
204− insertEmail = insertRow #emails
205− ( Default `as` #id :*
206− Set (param @1) `as` #user_id :*
207− Set (param @2) `as` #email )
208− OnConflictDoNothing (Returning Nil)
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))
209215:}
210216
211217>>> printSQL insertUser
212−INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) ON CONFLICT DO NOTHING RETURNING "id" AS "fromOnly"
213−>>> printSQL insertEmail
214−INSERT INTO "emails" ("id", "user_id", "email") VALUES (DEFAULT, ($1 :: int4), ($2 :: text)) ON CONFLICT DO NOTHING
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"
215219```
216220
217−Next we write a `Query` to retrieve users from the database. We're not
221+Next we write a `Query_` to retrieve users from the database. We're not
218222interested in the ids here, just the usernames and email addresses. We
219−need to use an inner join to get the right result. A `Query` is like a
220−`Manipulation` with the same kind of type parameters.
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.
221225
222226```Haskell
223227>>> :{
224228let
225− getUsers :: Query Schema '[]
226− '[ "userName" ::: 'NotNull 'PGtext
227− , "userEmail" ::: 'Null 'PGtext ]
228− getUsers = select
229+ getUsers :: Query_ Schemas () User
230+ getUsers = select_
229231 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)
230232 ( from (table (#users `as` #u)
231233 & innerJoin (table (#emails `as` #e))
@@ -236,25 +238,13 @@ let
236238SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")
237239```
238240
239−Now that we've defined the SQL side of things, we'll need a Haskell type
240−for users. We give the type `Generics.SOP.Generic` and
241−`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows
242−we receive when we run `getUsers`. Notice that the record fields of the
243−`User` type match the column names of `getUsers`.
244−
245−```Haskell
246−>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
247−>>> instance SOP.Generic User
248−>>> instance SOP.HasDatatypeInfo User
249−```
250−
251−Let's also create some users to add to the database.
241+Let's create some users to add to the database.
252242
253243```Haskell
254244>>> :{
255245let
256246 users :: [User]
257− users =
247+ users =
258248 [ User "Alice" (Just "alice@gmail.com")
259249 , User "Bob" Nothing
260250 , User "Carole" (Just "carole@hotmail.com")
@@ -273,19 +263,18 @@ transformer and when the schema doesn't change we can use `Monad` and
273263```Haskell
274264>>> :{
275265let
276− session :: PQ Schema Schema IO ()
266+ session :: PQ Schemas Schemas IO ()
277267 session = do
278− idResults <- traversePrepared insertUser (Only . userName <$> users)
279− ids <- traverse (fmap fromOnly . getRow 0) idResults
280− traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
268+ _ <- traversePrepared_ insertUser users
281269 usersResult <- runQuery getUsers
282270 usersRows <- getRows usersResult
283− liftBase $ print (usersRows :: [User])
271+ liftIO $ print (usersRows :: [User])
284272in
285− void . withConnection "host=localhost port=5432 dbname=exampledb" $
273+ withConnection "host=localhost port=5432 dbname=exampledb" $
286274 define setup
287275 & pqThen session
288276 & pqThen (define teardown)
289277:}
290278[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
279+-}
291280```
RELEASE NOTES.md+400
@@ -1,5 +1,405 @@
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+
3403### Version 0.4
4404
5405Version 0.4 strengthens Squeal's type system, adds
squeal-postgresql/exe/Example.hs+15−13
@@ -11,8 +11,7 @@
1111
1212module Main (main, main2) where
1313
14−import Control.Monad (void)
15−import Control.Monad.Base (liftBase, MonadBase)
14+import Control.Monad.IO.Class (MonadIO (..))
1615import Data.Int (Int16, Int32)
1716import Data.Monoid ((<>))
1817import Data.Text (Text)
@@ -39,6 +38,7 @@ type Schema =
3938 , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
4039 , "email" ::: 'NoDef :=> 'Null 'PGtext
4140 ])
41+ , "positive" ::: 'Typedef 'PGfloat4
4242 ]
4343
4444type Schemas = Public Schema
@@ -53,23 +53,25 @@ setup =
5353 >>>
5454 createTable #emails
5555 ( serial `as` #id :*
56− (int & notNullable) `as` #user_id :*
57− (text & nullable) `as` #email )
56+ hask @Int32 `as` #user_id :*
57+ hask @(Maybe Text) `as` #email )
5858 ( primaryKey #id `as` #pk_emails :*
5959 foreignKey #user_id #users #id
6060 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
61+ >>>
62+ createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
6163
6264teardown :: Definition Schemas (Public '[])
63−teardown = dropTable #emails >>> dropTable #users
65+teardown = dropType #positive >>> dropTable #emails >>> dropTable #users
6466
6567insertUser :: Manipulation_ Schemas (Text, VarArray (Vector (Maybe Int16))) (Only Int32)
6668insertUser = insertInto #users
67− (Values_ (defaultAs #id :* param @1 `as` #name :* param @2 `as` #vec))
69+ (Values_ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec))
6870 (OnConflict (OnConstraint #pk_users) DoNothing) (Returning_ (#id `as` #fromOnly))
6971
7072insertEmail :: Manipulation_ Schemas (Int32, Maybe Text) ()
7173insertEmail = insertInto_ #emails
72− (Values_ (defaultAs #id :* param @1 `as` #user_id :* param @2 `as` #email))
74+ (Values_ (Default `as` #id :* Set (param @1) `as` #user_id :* Set (param @2) `as` #email))
7375
7476getUsers :: Query_ Schemas () User
7577getUsers = select_
@@ -84,22 +86,22 @@ instance SOP.Generic User
8486instance SOP.HasDatatypeInfo User
8587
8688users :: [User]
87−users =
89+users =
8890 [ User "Alice" (Just "alice@gmail.com") (VarArray [Nothing, Just 1])
8991 , User "Bob" Nothing (VarArray [Just 2, Nothing])
9092 , User "Carole" (Just "carole@hotmail.com") (VarArray [Just 3])
9193 ]
9294
93−session :: (MonadBase IO pq, MonadPQ Schemas pq) => pq ()
95+session :: (MonadIO pq, MonadPQ Schemas pq) => pq ()
9496session = do
95− liftBase $ Char8.putStrLn "manipulating"
97+ liftIO $ Char8.putStrLn "manipulating"
9698 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])
9799 ids <- traverse (fmap fromOnly . getRow 0) idResults
98100 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))
99− liftBase $ Char8.putStrLn "querying"
101+ liftIO $ Char8.putStrLn "querying"
100102 usersResult <- runQuery getUsers
101103 usersRows <- getRows usersResult
102− liftBase $ print (usersRows :: [User])
104+ liftIO $ print (usersRows :: [User])
103105
104106main :: IO ()
105107main = do
@@ -117,7 +119,7 @@ main = do
117119
118120main2 :: IO ()
119121main2 =
120− void . withConnection "host=localhost port=5432 dbname=exampledb" $
122+ withConnection "host=localhost port=5432 dbname=exampledb" $
121123 define setup
122124 & pqThen session
123125 & pqThen (define teardown)
squeal-postgresql/squeal-postgresql.cabal+58−16
@@ -1,5 +1,5 @@
11name: squeal-postgresql
2−version: 0.4.9.0
2+version: 0.5.1.0
33synopsis: Squeal PostgreSQL Library
44description: Squeal is a type-safe embedding of PostgreSQL in Haskell
55homepage: https://github.com/morphismtech/squeal
@@ -22,12 +22,40 @@ library
2222 hs-source-dirs: src
2323 exposed-modules:
2424 Squeal.PostgreSQL
25+ Squeal.PostgreSQL.Alias
2526 Squeal.PostgreSQL.Binary
2627 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
2735 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
2855 Squeal.PostgreSQL.Manipulation
2956 Squeal.PostgreSQL.Migration
3057 Squeal.PostgreSQL.Pool
58+ Squeal.PostgreSQL.PG
3159 Squeal.PostgreSQL.PQ
3260 Squeal.PostgreSQL.Render
3361 Squeal.PostgreSQL.Query
@@ -42,10 +70,9 @@ library
4270 , bytestring >= 0.10.8.2
4371 , bytestring-strict-builder >= 0.4.5
4472 , deepseq >= 1.4.3.0
45− , generics-sop >= 0.3.2.0
46− , lifted-base >= 0.2.3.12
73+ , free-categories >= 0.1.0.0
74+ , generics-sop >= 0.3.2.0 && < 0.5.0.0
4775 , mmorph >= 1.1.1
48− , monad-control >= 1.0.2.3
4976 , mtl >= 2.2.2
5077 , network-ip >= 0.3.0.2
5178 , postgresql-binary >= 0.12.1
@@ -56,39 +83,55 @@ library
5683 , text >= 1.2.3.0
5784 , time >= 1.8.0.2
5885 , transformers >= 0.5.2.0
59− , transformers-base >= 0.4.4
86+ , unliftio >= 0.2.10
87+ , unliftio-pool >= 0.2.1.0
6088 , uuid-types >= 1.0.3
6189 , vector >= 0.12.0.1
6290
63−test-suite squeal-postgresql-doctest
91+test-suite doctest
6492 default-language: Haskell2010
6593 type: exitcode-stdio-1.0
6694 hs-source-dirs: test
6795 ghc-options: -Wall
68− main-is: DocTest.hs
96+ main-is: Doc.hs
6997 build-depends:
7098 base >= 4.10.0.0
7199 , doctest >= 0.11.4
100+ , squeal-postgresql
72101
73−test-suite squeal-postgresql-specs
102+test-suite properties
74103 default-language: Haskell2010
75104 type: exitcode-stdio-1.0
76− hs-source-dirs: test/Specs
77− ghc-options: -Wall -main-is Specs
78− main-is: Specs.hs
79− other-modules: ExceptionHandling
105+ hs-source-dirs: test
106+ ghc-options: -Wall
107+ main-is: Property.hs
80108 build-depends:
81109 base >= 4.10.0.0
82110 , 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
83127 , generics-sop >= 0.3.1.0
84128 , hspec >= 2.4.8
129+ , mtl >= 2.2.2
85130 , squeal-postgresql
86131 , text >= 1.2.2.2
87− , transformers >= 0.5.2.0
88− , transformers-base >= 0.4.4
89132 , vector >= 0.12.0.1
90133
91−executable squeal-postgresql-example
134+executable example
92135 default-language: Haskell2010
93136 hs-source-dirs: exe
94137 ghc-options: -Wall
@@ -101,5 +144,4 @@ executable squeal-postgresql-example
101144 , squeal-postgresql
102145 , text >= 1.2.2.2
103146 , transformers >= 0.5.2.0
104− , transformers-base >= 0.4.4
105147 , vector >= 0.12.0.1
squeal-postgresql/src/Squeal/PostgreSQL.hs+70−51
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL
3−Description: Squeel export module
4−Copyright: (c) Eitan Chatav, 2017
3+Description: Squeal export module
4+Copyright: (c) Eitan Chatav, 2019
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -11,17 +11,15 @@ Let's see an example!
1111First, we need some language extensions because Squeal uses modern GHC
1212features.
1313
14−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels
14+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts
1515>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs
1616
1717We'll need some imports.
1818
19−>>> import Control.Monad (void)
20−>>> import Control.Monad.Base (liftBase)
19+>>> import Control.Monad.IO.Class (liftIO)
2120>>> import Data.Int (Int32)
2221>>> import Data.Text (Text)
2322>>> import Squeal.PostgreSQL
24−>>> import Squeal.PostgreSQL.Render
2523
2624We'll use generics to easily convert between Haskell and PostgreSQL values.
2725
@@ -60,7 +58,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,
6058yielding a `ColumnType`. It is intended to connote Haskell's @=>@ operator
6159
6260Next, we'll write `Definition`s to set up and tear down the schema. In
63−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
61+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`
6462has two type parameters, corresponding to the schema
6563before being run and the schema after. We can compose definitions using `>>>`.
6664Here and in the rest of our commands we make use of overloaded
@@ -69,7 +67,7 @@ labels to refer to named tables and columns in our schema.
6967>>> :{
7068let
7169 setup :: Definition (Public '[]) Schemas
72− setup =
70+ setup =
7371 createTable #users
7472 ( serial `as` #id :*
7573 (text & notNullable) `as` #name )
@@ -104,25 +102,23 @@ let
104102DROP TABLE "emails";
105103DROP TABLE "users";
106104
107−Next, we'll write `Manipulation`s to insert data into our two tables.
108−A `Manipulation` like `insertInto`, `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
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
111116we insert into the users table, we will need a parameter for the @name@
112117field but not for the @id@ field. Since it's serial, we can use a default
113118value. However, since the emails table refers to the users table, we will
114119need to retrieve the user id that the insert generates and insert it into
115−the emails table. Take a careful look at the type and definition of both
116−of our inserts.
117−
118−We'll need a Haskell type for users. We give the type `Generics.SOP.Generic` and
119−`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows
120−we receive when we run @getUsers@. Notice that the record fields of the
121−@User@ type match the column names of @getUsers@.
122−
123−>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
124−>>> instance SOP.Generic User
125−>>> instance SOP.HasDatatypeInfo User
120+the emails table. We can do this in a single `Manipulation_` by using a
121+`with` statement.
126122
127123>>> :{
128124let
@@ -130,19 +126,20 @@ let
130126 insertUser = with (u `as` #u) e
131127 where
132128 u = insertInto #users
133− (Values_ (defaultAs #id :* param @1 `as` #name))
129+ (Values_ (Default `as` #id :* Set (param @1) `as` #name))
134130 OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))
135− e = insertInto_ #emails
136− (Select (defaultAs #id :* #u ! #id `as` #user_id :* #u ! #email) (from (common #u)))
131+ e = insertInto_ #emails $ Select
132+ (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)
133+ (from (common #u))
137134:}
138135
139136>>> printSQL insertUser
140137WITH "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"
141138
142−Next we write a `Query` to retrieve users from the database. We're not
139+Next we write a `Query_` to retrieve users from the database. We're not
143140interested in the ids here, just the usernames and email addresses. We
144−need to use an inner join to get the right result. A `Query` is like a
145−`Manipulation` with the same kind of type parameters.
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.
146143
147144>>> :{
148145let
@@ -162,7 +159,7 @@ Let's create some users to add to the database.
162159>>> :{
163160let
164161 users :: [User]
165− users =
162+ users =
166163 [ User "Alice" (Just "alice@gmail.com")
167164 , User "Bob" Nothing
168165 , User "Carole" (Just "carole@hotmail.com")
@@ -184,31 +181,53 @@ let
184181 _ <- traversePrepared_ insertUser users
185182 usersResult <- runQuery getUsers
186183 usersRows <- getRows usersResult
187− liftBase $ print (usersRows :: [User])
184+ liftIO $ print (usersRows :: [User])
188185in
189− void . withConnection "host=localhost port=5432 dbname=exampledb" $
186+ withConnection "host=localhost port=5432 dbname=exampledb" $
190187 define setup
191188 & pqThen session
192189 & pqThen (define teardown)
193190:}
194191[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]
195192-}
196−module Squeal.PostgreSQL
197− ( module Squeal.PostgreSQL.Binary
198− , module Squeal.PostgreSQL.Definition
199− , module Squeal.PostgreSQL.Expression
200− , module Squeal.PostgreSQL.Manipulation
201− , module Squeal.PostgreSQL.PQ
202− , module Squeal.PostgreSQL.Query
203− , module Squeal.PostgreSQL.Schema
204− , module Squeal.PostgreSQL.Transaction
205− ) where
206−
207−import Squeal.PostgreSQL.Binary
208−import Squeal.PostgreSQL.Definition
209−import Squeal.PostgreSQL.Expression
210−import Squeal.PostgreSQL.Manipulation
211−import Squeal.PostgreSQL.PQ
212−import Squeal.PostgreSQL.Query
213−import Squeal.PostgreSQL.Schema
214−import Squeal.PostgreSQL.Transaction
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
squeal-postgresql/src/Squeal/PostgreSQL/Alias.hsnew file+249
@@ -0,0 +1,249 @@
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+221−332
@@ -16,7 +16,7 @@ Let's see some examples. We'll need some imports
1616>>> import Data.Int (Int16)
1717>>> import Data.Text (Text)
1818>>> import Control.Monad (void)
19−>>> import Control.Monad.Base (liftBase)
19+>>> import Control.Monad.IO.Class (liftIO)
2020>>> import Squeal.PostgreSQL
2121
2222Define a Haskell datatype @Row@ that will serve as both the input and output of a simple
@@ -39,10 +39,10 @@ the input and output should be equal.
3939
4040>>> let input = Row 2 "hi" (Just True)
4141>>> :{
42−void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
42+withConnection "host=localhost port=5432 dbname=exampledb" $ do
4343 result <- runQueryParams roundTrip input
4444 Just output <- firstRow result
45− liftBase . print $ input == output
45+ liftIO . print $ input == output
4646:}
4747True
4848
@@ -78,10 +78,10 @@ let
7878>>> :set -XOverloadedLists
7979>>> let input = Row (VarArray [1,2]) (FixArray (Just 1,Nothing)) (FixArray ((1,2),(3,4),(5,6)))
8080>>> :{
81−void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
81+withConnection "host=localhost port=5432 dbname=exampledb" $ do
8282 result <- runQueryParams roundTrip input
8383 Just output <- firstRow result
84− liftBase . print $ input == output
84+ liftIO . print $ input == output
8585:}
8686True
8787
@@ -168,9 +168,9 @@ let
168168 session = do
169169 result <- runQueryParams roundTrip input
170170 Just output <- firstRow result
171− liftBase . print $ input == output
171+ liftIO . print $ input == output
172172in
173− void . withConnection "host=localhost port=5432 dbname=exampledb" $
173+ withConnection "host=localhost port=5432 dbname=exampledb" $
174174 define setup
175175 & pqThen session
176176 & pqThen (define teardown)
@@ -202,45 +202,37 @@ True
202202#-}
203203
204204module Squeal.PostgreSQL.Binary
205− ( -- * PG type families
206− PG
207− , NullPG
208− , TuplePG
209− , RowPG
210− , LabelsPG
211− -- * Storage newtypes
212− , Money (..)
213− , Json (..)
214− , Jsonb (..)
215− , Composite (..)
216− , Enumerated (..)
217− , VarArray (..)
218− , FixArray (..)
219− -- * Encoding
220− , ToParam (..)
205+ ( -- * Encoding
206+ ToParam (..)
221207 , ToParams (..)
208+ , ToNullityParam (..)
209+ , ToField (..)
210+ , ToFixArray (..)
222211 -- * Decoding
223212 , FromValue (..)
224213 , FromRow (..)
214+ , FromField (..)
215+ , FromFixArray (..)
225216 -- * Only
226217 , Only (..)
227− , P (..)
218+ -- * Oid
219+ , OidOf (..)
220+ , OidOfParam (..)
221+ , OidOfField (..)
228222 ) where
229223
230224import BinaryParser
231225import ByteString.StrictBuilder (builderLength, int32BE, int64BE, word32BE)
232226import Control.Arrow (left)
233227import Control.Monad
234−import Data.Aeson (Value)
235−import Data.ByteString (ByteString)
236228import Data.Int
237229import Data.Kind
238230import Data.Scientific
239−import Data.Text (Text)
240231import Data.Time
241232import Data.UUID.Types
242233import Data.Vector (Vector)
243234import Data.Word
235+import Foreign.C.Types (CUInt(CUInt))
244236import Generics.SOP
245237import Generics.SOP.Record
246238import GHC.TypeLits
@@ -254,11 +246,14 @@ import qualified Data.Text.Lazy as Lazy (Text)
254246import qualified Data.Text as Strict (Text)
255247import qualified Data.Text as Strict.Text
256248import qualified Data.Vector as Vector
257−import qualified Generics.SOP.Type.Metadata as Type
249+import qualified Database.PostgreSQL.LibPQ as LibPQ
258250import qualified GHC.Generics as GHC
259251import qualified PostgreSQL.Binary.Decoding as Decoding
260252import qualified PostgreSQL.Binary.Encoding as Encoding
261253
254+import Squeal.PostgreSQL.Alias
255+import Squeal.PostgreSQL.List
256+import Squeal.PostgreSQL.PG
262257import Squeal.PostgreSQL.Schema
263258
264259-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into
@@ -282,11 +277,9 @@ class ToParam (x :: Type) (pg :: PGType) where
282277 toParam :: x -> K Encoding.Encoding pg
283278instance ToParam Bool 'PGbool where toParam = K . Encoding.bool
284279instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16
285−instance ToParam Word16 'PGint2 where toParam = K . Encoding.int2_word16
286280instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32
287−instance ToParam Word32 'PGint4 where toParam = K . Encoding.int4_word32
288281instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64
289−instance ToParam Word64 'PGint8 where toParam = K . Encoding.int8_word64
282+instance ToParam Oid 'PGoid where toParam = K . Encoding.int4_word32 . getOid
290283instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4
291284instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8
292285instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric
@@ -319,24 +312,26 @@ instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where
319312instance Aeson.ToJSON x => ToParam (Jsonb x) 'PGjsonb where
320313 toParam = K . Encoding.jsonb_bytes
321314 . Lazy.ByteString.toStrict . Aeson.encode . getJsonb
322−instance (ToNullityParam x ty, ty ~ nullity pg, HasOid pg)
315+instance (ToNullityParam x ty, ty ~ nullity pg, OidOf pg)
323316 => ToParam (VarArray [x]) ('PGvararray ty) where
324317 toParam = K
325− . Encoding.array_foldable (oid @pg) (unK . toNullityParam @x @ty)
318+ . Encoding.array_foldable
319+ (getOid (oidOf @pg)) (unK . toNullityParam @x @ty)
326320 . getVarArray
327−instance (ToParam x pg, HasOid pg)
321+instance (ToParam x pg, OidOf pg)
328322 => ToParam (VarArray (Vector x)) ('PGvararray ('NotNull pg)) where
329323 toParam = K
330− . Encoding.array_vector (oid @pg) (unK . toParam @x @pg)
324+ . Encoding.array_vector (getOid (oidOf @pg)) (unK . toParam @x @pg)
331325 . getVarArray
332−instance (ToParam x pg, HasOid pg)
326+instance (ToParam x pg, OidOf pg)
333327 => ToParam (VarArray (Vector (Maybe x))) ('PGvararray ('Null pg)) where
334328 toParam = K
335− . Encoding.nullableArray_vector (oid @pg) (unK . toParam @x @pg)
329+ . Encoding.nullableArray_vector
330+ (getOid (oidOf @pg)) (unK . toParam @x @pg)
336331 . getVarArray
337−instance (ToFixArray x dims ty, ty ~ nullity pg, HasOid pg)
332+instance (ToFixArray x dims ty, ty ~ nullity pg, OidOf pg)
338333 => ToParam (FixArray x) ('PGfixarray dims ty) where
339− toParam = K . Encoding.array (oid @pg)
334+ toParam = K . Encoding.array (getOid (oidOf @pg))
340335 . unK . unK . toFixArray @x @dims @ty . getFixArray
341336instance
342337 ( IsEnumType x
@@ -361,7 +356,7 @@ instance
361356 ( SListI fields
362357 , IsRecord x xs
363358 , AllZip ToField xs fields
364− , All HasAliasedOid fields
359+ , All OidOfField fields
365360 ) => ToParam (Composite x) ('PGcomposite fields) where
366361 toParam =
367362 let
@@ -369,7 +364,7 @@ instance
369364 encoders = htrans (Proxy @ToField) toField
370365
371366 composite
372− :: All HasAliasedOid row
367+ :: All OidOfField row
373368 => NP (K (Maybe Encoding.Encoding)) row
374369 -> K Encoding.Encoding ('PGcomposite row)
375370 composite fields = K $
@@ -386,27 +381,142 @@ instance
386381 int32BE (fromIntegral (lengthSList (Proxy @xs))) <>
387382 let
388383 each
389− :: HasAliasedOid field
384+ :: OidOfField field
390385 => K (Maybe Encoding.Encoding) field
391386 -> Encoding.Encoding
392387 each (K field :: K (Maybe Encoding.Encoding) field) =
393− word32BE (aliasedOid @field)
388+ word32BE (getOid (oidOfField @field))
394389 <> case field of
395390 Nothing -> int64BE (-1)
396391 Just value ->
397392 int32BE (fromIntegral (builderLength value))
398393 <> value
399394 in
400− hcfoldMap (Proxy @HasAliasedOid) each fields
395+ hcfoldMap (Proxy @OidOfField) each fields
401396
402397 in
403398 composite . encoders . toRecord . getComposite
404399
405−class HasAliasedOid (field :: (Symbol, NullityType)) where
406− aliasedOid :: Word32
407−instance HasOid ty => HasAliasedOid (alias ::: nullity ty) where
408− aliasedOid = oid @ty
409−
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`.
410520class ToNullityParam (x :: Type) (ty :: NullityType) where
411521 toNullityParam :: x -> K (Maybe Encoding.Encoding) ty
412522instance ToParam x pg => ToNullityParam x ('NotNull pg) where
@@ -414,11 +524,19 @@ instance ToParam x pg => ToNullityParam x ('NotNull pg) where
414524instance ToParam x pg => ToNullityParam (Maybe x) ('Null pg) where
415525 toNullityParam = K . fmap (unK . toParam @x @pg)
416526
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.
417531class ToField (x :: (Symbol, Type)) (field :: (Symbol, NullityType)) where
418532 toField :: P x -> K (Maybe Encoding.Encoding) field
419533instance ToNullityParam x ty => ToField (alias ::: x) (alias ::: ty) where
420534 toField (P x) = K . unK $ toNullityParam @x @ty x
421535
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.
422540class ToFixArray (x :: Type) (dims :: [Nat]) (array :: NullityType) where
423541 toFixArray :: x -> K (K Encoding.Array dims) array
424542instance ToNullityParam x ty => ToFixArray x '[] ty where
@@ -464,6 +582,7 @@ instance FromValue 'PGbool Bool where fromValue = Decoding.bool
464582instance FromValue 'PGint2 Int16 where fromValue = Decoding.int
465583instance FromValue 'PGint4 Int32 where fromValue = Decoding.int
466584instance FromValue 'PGint8 Int64 where fromValue = Decoding.int
585+instance FromValue 'PGoid Word32 where fromValue = Decoding.int
467586instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4
468587instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8
469588instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric
@@ -602,6 +721,10 @@ instance FromValue pg y
602721 K (Just bytestring) -> P . Just <$>
603722 Decoding.valueParser (fromValue @pg) bytestring
604723
724+-- | A `FromFixArray` constraint gives a decoding to a Haskell `Type`
725+-- from the binary format of a PostgreSQL fixed-length array.
726+-- You should not define instances for
727+-- `FromFixArray`, just use the provided instances.
605728class FromFixArray (dims :: [Nat]) (ty :: NullityType) (y :: Type) where
606729 fromFixArray :: Decoding.Array y
607730instance FromValue pg y => FromFixArray '[] ('NotNull pg) y where
@@ -646,50 +769,53 @@ instance
646769 = fmap fromRecord
647770 . hsequence'
648771 . htrans (Proxy @FromField) fromField
649−instance (FromField (col ::: pg) (col ::: hask))
650− => FromRow '[col ::: pg] (P (col ::: hask)) where
651− fromRow (pg :* Nil) = (unComp . fromField) pg
652−instance
653− ( row ~ Join row1 row2
654− , FromRow row1 hask1
655− , FromRow row2 hask2
656− , SListI row
657− ) => FromRow row (hask1, hask2) where
658− fromRow row = case disjoin @row1 @row2 row of
659− (row1, row2) -> (,) <$> fromRow row1 <*> fromRow row2
660−instance
661− ( row ~ Join row1 row23
662− , FromRow row1 hask1
663− , FromRow row23 (hask2, hask3)
664− , SListI row
665− ) => FromRow row (hask1, hask2, hask3) where
666− fromRow row = case disjoin @row1 @row23 row of
667− (row1, row23) -> do
668− hask1 <- fromRow row1
669− (hask2, hask3) <- fromRow row23
670− return (hask1, hask2, hask3)
671−instance
672− ( row ~ Join row1 row234
673− , FromRow row1 hask1
674− , FromRow row234 (hask2, hask3, hask4)
675− , SListI row
676− ) => FromRow row (hask1, hask2, hask3, hask4) where
677− fromRow row = case disjoin @row1 @row234 row of
678− (row1, row234) -> do
679− hask1 <- fromRow row1
680− (hask2, hask3, hask4) <- fromRow row234
681− return (hask1, hask2, hask3, hask4)
682−instance
683− ( row ~ Join row1 row2345
684− , FromRow row1 hask1
685− , FromRow row2345 (hask2, hask3, hask4, hask5)
686− , SListI row
687− ) => FromRow row (hask1, hask2, hask3, hask4, hask5) where
688− fromRow row = case disjoin @row1 @row2345 row of
689− (row1, row2345) -> do
690− hask1 <- fromRow row1
691− (hask2, hask3, hask4, hask5) <- fromRow row2345
692− return (hask1, hask2, hask3, hask4, hask5)
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)
693819
694820-- | `Only` is a 1-tuple type, useful for encoding a single parameter with
695821-- `toParams` or decoding a single value with `fromRow`.
@@ -718,242 +844,5 @@ replicateMN
718844replicateMN mx = hsequence' $
719845 hcpure (Proxy :: Proxy ((~) x)) (Comp (I <$> mx))
720846
721−{- | The `Money` newtype stores a monetary value in terms
722−of the number of cents, i.e. @$2,000.20@ would be expressed as
723−@Money { cents = 200020 }@.
724−
725−>>> import Control.Monad (void)
726−>>> import Control.Monad.Base (liftBase)
727−>>> import Squeal.PostgreSQL
728−>>> :{
729−let
730− roundTrip :: Query_ (Public '[]) (Only Money) (Only Money)
731− roundTrip = values_ $ parameter @1 money `as` #fromOnly
732−:}
733−
734−>>> let input = Only (Money 20020)
735−
736−>>> :{
737−void . withConnection "host=localhost port=5432 dbname=exampledb" $ do
738− result <- runQueryParams roundTrip input
739− Just output <- firstRow result
740− liftBase . print $ input == output
741−:}
742−True
743−-}
744−newtype Money = Money { cents :: Int64 }
745− deriving (Eq, Ord, Show, Read, GHC.Generic)
746−type instance PG Money = 'PGmoney
747−
748−{- | The `Json` newtype is an indication that the Haskell
749−type it's applied to should be stored as a `PGjson`.
750−-}
751−newtype Json hask = Json {getJson :: hask}
752− deriving (Eq, Ord, Show, Read, GHC.Generic)
753−type instance PG (Json hask) = 'PGjson
754−
755−{- | The `Jsonb` newtype is an indication that the Haskell
756−type it's applied to should be stored as a `PGjsonb`.
757−-}
758−newtype Jsonb hask = Jsonb {getJsonb :: hask}
759− deriving (Eq, Ord, Show, Read, GHC.Generic)
760−type instance PG (Jsonb hask) = 'PGjsonb
761−
762−{- | The `Composite` newtype is an indication that the Haskell
763−type it's applied to should be stored as a `PGcomposite`.
764−-}
765−newtype Composite record = Composite {getComposite :: record}
766− deriving (Eq, Ord, Show, Read, GHC.Generic)
767−type instance PG (Composite hask) = 'PGcomposite (RowPG hask)
768−
769−{- | The `Enumerated` newtype is an indication that the Haskell
770−type it's applied to should be stored as a `PGenum`.
771−-}
772−newtype Enumerated enum = Enumerated {getEnumerated :: enum}
773− deriving (Eq, Ord, Show, Read, GHC.Generic)
774−type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)
775−
776−{- | The `VarArray` newtype is an indication that the Haskell
777−type it's applied to should be stored as a `PGvararray`.
778−-}
779−newtype VarArray arr = VarArray {getVarArray :: arr}
780− deriving (Eq, Ord, Show, Read, GHC.Generic)
781−type instance PG (VarArray (Vector hask)) = 'PGvararray (NullPG hask)
782−
783−{- | The `FixArray` newtype is an indication that the Haskell
784−type it's applied to should be stored as a `PGfixarray`.
785−-}
786−newtype FixArray arr = FixArray {getFixArray :: arr}
787− deriving (Eq, Ord, Show, Read, GHC.Generic)
788−type instance PG (FixArray x) = 'PGfixarray (DimPG x) (FixPG x)
789−
790−type family DimPG (hask :: Type) :: [Nat] where
791− DimPG (x,x) = 2 ': DimPG x
792− DimPG (x,x,x) = 3 ': DimPG x
793− DimPG (x,x,x,x) = 4 ': DimPG x
794− DimPG (x,x,x,x,x) = 5 ': DimPG x
795− DimPG (x,x,x,x,x,x) = 6 ': DimPG x
796− DimPG (x,x,x,x,x,x,x) = 7 ': DimPG x
797− DimPG (x,x,x,x,x,x,x,x) = 8 ': DimPG x
798− DimPG (x,x,x,x,x,x,x,x,x) = 9 ': DimPG x
799− DimPG (x,x,x,x,x,x,x,x,x,x) = 10 ': DimPG x
800− DimPG x = '[]
801−
802−type family FixPG (hask :: Type) :: NullityType where
803− FixPG (x,x) = FixPG x
804− FixPG (x,x,x) = FixPG x
805− FixPG (x,x,x,x) = FixPG x
806− FixPG (x,x,x,x,x) = FixPG x
807− FixPG (x,x,x,x,x,x) = FixPG x
808− FixPG (x,x,x,x,x,x,x) = FixPG x
809− FixPG (x,x,x,x,x,x,x,x) = FixPG x
810− FixPG (x,x,x,x,x,x,x,x,x) = FixPG x
811− FixPG (x,x,x,x,x,x,x,x,x,x) = FixPG x
812− FixPG (x,x,x,x,x,x,x,x,x,x,x) = FixPG x
813− FixPG x = NullPG x
814−
815−{- | The `PG` type family embeds a subset of Haskell types
816−as Postgres types. As an open type family, `PG` is extensible.
817−
818−>>> :kind! PG LocalTime
819−PG LocalTime :: PGType
820−= 'PGtimestamp
821−
822−>>> newtype MyDouble = My Double
823−>>> :set -XTypeFamilies
824−>>> type instance PG MyDouble = 'PGfloat8
825−-}
826−type family PG (hask :: Type) :: PGType
827−type instance PG Bool = 'PGbool
828−type instance PG Int16 = 'PGint2
829−type instance PG Int32 = 'PGint4
830−type instance PG Int64 = 'PGint8
831−type instance PG Word16 = 'PGint2
832−type instance PG Word32 = 'PGint4
833−type instance PG Word64 = 'PGint8
834−type instance PG Scientific = 'PGnumeric
835−type instance PG Float = 'PGfloat4
836−type instance PG Double = 'PGfloat8
837−type instance PG Char = 'PGchar 1
838−type instance PG Text = 'PGtext
839−type instance PG Lazy.Text = 'PGtext
840−type instance PG String = 'PGtext
841−type instance PG ByteString = 'PGbytea
842−type instance PG Lazy.ByteString = 'PGbytea
843−type instance PG LocalTime = 'PGtimestamp
844−type instance PG UTCTime = 'PGtimestamptz
845−type instance PG Day = 'PGdate
846−type instance PG TimeOfDay = 'PGtime
847−type instance PG (TimeOfDay, TimeZone) = 'PGtimetz
848−type instance PG DiffTime = 'PGinterval
849−type instance PG UUID = 'PGuuid
850−type instance PG (NetAddr IP) = 'PGinet
851−type instance PG Value = 'PGjson
852−
853−{-| The `LabelsPG` type family calculates the constructors of a
854−Haskell enum type.
855−
856−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
857−>>> instance Generic Schwarma
858−>>> instance HasDatatypeInfo Schwarma
859−>>> :kind! LabelsPG Schwarma
860−LabelsPG Schwarma :: [Type.ConstructorName]
861−= '["Beef", "Lamb", "Chicken"]
862−-}
863−type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where
864− LabelsPG hask =
865− ConstructorNamesOf (ConstructorsOf (DatatypeInfoOf hask))
866−
867−{- | `RowPG` turns a Haskell record type into a `RowType`.
868−
869−>>> data Person = Person { name :: Text, age :: Int32 } deriving GHC.Generic
870−>>> instance Generic Person
871−>>> instance HasDatatypeInfo Person
872−>>> :kind! RowPG Person
873−RowPG Person :: [(Symbol, NullityType)]
874−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]
875−-}
876−type family RowPG (hask :: Type) :: RowType where
877− RowPG (hask1, hask2) = Join (RowPG hask1) (RowPG hask2)
878− RowPG (hask1, hask2, hask3) =
879− Join (RowPG hask1) (RowPG (hask2, hask3))
880− RowPG (hask1, hask2, hask3, hask4) =
881− Join (RowPG hask1) (RowPG (hask2, hask3, hask4))
882− RowPG (hask1, hask2, hask3, hask4, hask5) =
883− Join (RowPG hask1) (RowPG (hask2, hask3, hask4, hask5))
884− RowPG (P (col ::: head)) = '[col ::: NullPG head]
885− RowPG hask = RowOf (RecordCodeOf hask)
886−
887−type family RowOf (fields :: [(Symbol, Type)]) :: RowType where
888− RowOf '[] = '[]
889− RowOf (field ': fields) = FieldPG field ': RowOf fields
890−
891−type family FieldPG (field :: (Symbol, Type)) :: (Symbol, NullityType) where
892− FieldPG (field ::: hask) = field ::: NullPG hask
893−
894−{- | `NullPG` turns a Haskell type into a `NullityType`.
895−
896−>>> :kind! NullPG Double
897−NullPG Double :: NullityType
898−= 'NotNull 'PGfloat8
899−>>> :kind! NullPG (Maybe Double)
900−NullPG (Maybe Double) :: NullityType
901−= 'Null 'PGfloat8
902−-}
903−type family NullPG (hask :: Type) :: NullityType where
904− NullPG (Maybe hask) = 'Null (PG hask)
905− NullPG hask = 'NotNull (PG hask)
906−
907−{- | `TuplePG` turns a Haskell tuple type (including record types) into
908−the corresponding list of `NullityType`s.
909−
910−>>> :kind! TuplePG (Double, Maybe Char)
911−TuplePG (Double, Maybe Char) :: [NullityType]
912−= '[ 'NotNull 'PGfloat8, 'Null ('PGchar 1)]
913−-}
914−type family TuplePG (hask :: Type) :: [NullityType] where
915− TuplePG hask = TupleOf (TupleCodeOf hask (Code hask))
916−
917−type family TupleOf (tuple :: [Type]) :: [NullityType] where
918− TupleOf '[] = '[]
919− TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple
920−
921−type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where
922− TupleCodeOf hask '[tuple] = tuple
923− TupleCodeOf hask '[] =
924− TypeError
925− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."
926− ':$$: 'Text "It is a void type with no constructors."
927− )
928− TupleCodeOf hask (_ ': _ ': _) =
929− TypeError
930− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."
931− ':$$: 'Text "It is a sum type with more than one constructor."
932− )
933−
934−-- | Calculates constructors of a datatype.
935−type family ConstructorsOf (datatype :: Type.DatatypeInfo)
936− :: [Type.ConstructorInfo] where
937− ConstructorsOf ('Type.ADT _module _datatype constructors) =
938− constructors
939− ConstructorsOf ('Type.Newtype _module _datatype constructor) =
940− '[constructor]
941−
942−-- | Calculates the name of a nullary constructor, otherwise
943−-- generates a type error.
944−type family ConstructorNameOf (constructors :: Type.ConstructorInfo)
945− :: Type.ConstructorName where
946− ConstructorNameOf ('Type.Constructor name) = name
947− ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError
948− ('Text "ConstructorNameOf error: non-nullary constructor "
949− ':<>: 'Text name)
950− ConstructorNameOf ('Type.Record name _fields) = TypeError
951− ('Text "ConstructorNameOf error: non-nullary constructor "
952− ':<>: 'Text name)
953−
954−-- | Calculate the names of nullary constructors.
955−type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])
956− :: [Type.ConstructorName] where
957− ConstructorNamesOf '[] = '[]
958− ConstructorNamesOf (constructor ': constructors) =
959− ConstructorNameOf constructor ': ConstructorNamesOf constructors
847+getOid :: LibPQ.Oid -> Word32
848+getOid (LibPQ.Oid (CUInt oid)) = oid
squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+15−1012
@@ -11,13 +11,15 @@ Squeal data definition language.
1111{-# LANGUAGE
1212 AllowAmbiguousTypes
1313 , ConstraintKinds
14+ , DeriveAnyClass
1415 , DeriveGeneric
16+ , DerivingStrategies
1517 , FlexibleContexts
1618 , FlexibleInstances
1719 , GADTs
18− , GeneralizedNewtypeDeriving
1920 , LambdaCase
2021 , MultiParamTypeClasses
22+ , OverloadedLabels
2123 , OverloadedStrings
2224 , RankNTypes
2325 , ScopedTypeVariables
@@ -25,82 +27,31 @@ Squeal data definition language.
2527 , TypeInType
2628 , TypeOperators
2729 , UndecidableSuperClasses
30+ , UndecidableInstances
2831#-}
2932
3033module Squeal.PostgreSQL.Definition
3134 ( -- * Definition
3235 Definition (..)
3336 , (>>>)
34− -- * Tables
35− -- ** Create
36− , createSchema
37− , createSchemaIfNotExists
38− , createTable
39− , createTableIfNotExists
40− , createView
41− , createTypeEnum
42− , createTypeEnumFrom
43− , createTypeComposite
44− , createTypeCompositeFrom
45− , createDomain
46− , TableConstraintExpression (..)
47− , check
48− , unique
49− , primaryKey
50− , foreignKey
51− , ForeignKeyed
52− , OnDeleteClause (..)
53− , OnUpdateClause (..)
54− -- ** Drop
55− , dropSchema
56− , dropTable
57− , dropView
58− , dropType
59− -- ** Alter
60− , alterTable
61− , alterTableRename
62− , AlterTable (..)
63− , addConstraint
64− , dropConstraint
65− , AddColumn (..)
66− , dropColumn
67− , renameColumn
68− , alterColumn
69− , AlterColumn (..)
70− , setDefault
71− , dropDefault
72− , setNotNull
73− , dropNotNull
74− , alterType
75− -- * Columns
76− , ColumnTypeExpression (..)
77− , nullable
78− , notNullable
79− , default_
80− , serial2
81− , smallserial
82− , serial4
83− , serial
84− , serial8
85− , bigserial
37+ , manipDefinition
8638 ) where
8739
8840import Control.Category
8941import Control.DeepSeq
9042import Data.ByteString
9143import Data.Monoid
92−import GHC.TypeLits
9344import Prelude hiding ((.), id)
9445
95−import qualified Generics.SOP as SOP
9646import qualified GHC.Generics as GHC
9747
98−import Squeal.PostgreSQL.Binary
99−import Squeal.PostgreSQL.Expression
100−import Squeal.PostgreSQL.Query
48+import Squeal.PostgreSQL.Manipulation
10149import Squeal.PostgreSQL.Render
10250import Squeal.PostgreSQL.Schema
10351
52+-- $setup
53+-- >>> import Squeal.PostgreSQL
54+
10455{-----------------------------------------
10556statements
10657-----------------------------------------}
@@ -122,958 +73,10 @@ instance Category Definition where
12273 ddl1 . ddl0 = UnsafeDefinition $
12374 renderSQL ddl0 <> "\n" <> renderSQL ddl1
12475
125−{-----------------------------------------
126−CREATE statements
127−-----------------------------------------}
128−
129−createSchema
130− :: KnownSymbol sch
131− => Alias sch
132− -> Definition schemas (Create sch '[] schemas)
133−createSchema sch = UnsafeDefinition $
134− "CREATE" <+> "SCHEMA" <+> renderSQL sch <> ";"
135−
136−createSchemaIfNotExists
137− :: (KnownSymbol sch, Has sch schemas schema)
138− => Alias sch
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
13981 -> Definition schemas schemas
140−createSchemaIfNotExists sch = UnsafeDefinition $
141− "CREATE" <+> "SCHEMA" <+> "IF" <+> "NOT" <+> "EXISTS"
142− <+> renderSQL sch <> ";"
143−
144−{- | `createTable` adds a table to the schema.
145−
146−>>> :set -XOverloadedLabels
147−>>> :{
148−type Table = '[] :=>
149− '[ "a" ::: 'NoDef :=> 'Null 'PGint4
150− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
151−:}
152−
153−>>> :{
154−let
155− setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table])
156− setup = createTable #tab
157− (nullable int `as` #a :* nullable real `as` #b) Nil
158−in printSQL setup
159−:}
160−CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
161−-}
162−createTable
163− :: ( KnownSymbol sch
164− , KnownSymbol tab
165− , columns ~ (col ': cols)
166− , SOP.SListI columns
167− , SOP.SListI constraints
168− , Has sch schemas0 schema0
169− , schemas1 ~ Alter sch (Create tab ('Table (constraints :=> columns)) schema0) schemas0 )
170− => QualifiedAlias sch tab -- ^ the name of the table to add
171− -> NP (Aliased (ColumnTypeExpression schemas0)) columns
172− -- ^ the names and datatype of each column
173− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
174− -- ^ constraints that must hold for the table
175− -> Definition schemas0 schemas1
176−createTable tab columns constraints = UnsafeDefinition $
177− "CREATE TABLE" <+> renderCreation tab columns constraints
178−
179−{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.
180−Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.
181−`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in
182−the `Category` of `Definition`s.
183−
184−>>> :set -XOverloadedLabels -XTypeApplications
185−>>> :{
186−type Table = '[] :=>
187− '[ "a" ::: 'NoDef :=> 'Null 'PGint4
188− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
189−:}
190−
191−>>> type Schemas = Public '["tab" ::: 'Table Table]
192−
193−>>> :{
194−let
195− setup :: Definition Schemas Schemas
196− setup = createTableIfNotExists #tab
197− (nullable int `as` #a :* nullable real `as` #b) Nil
198−in printSQL setup
199−:}
200−CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);
201−-}
202−createTableIfNotExists
203− :: ( Has sch schemas schema
204− , Has tab schema ('Table (constraints :=> columns))
205− , SOP.SListI columns
206− , SOP.SListI constraints )
207− => QualifiedAlias sch tab -- ^ the name of the table to add
208− -> NP (Aliased (ColumnTypeExpression schemas)) columns
209− -- ^ the names and datatype of each column
210− -> NP (Aliased (TableConstraintExpression sch tab schemas)) constraints
211− -- ^ constraints that must hold for the table
212− -> Definition schemas schemas
213−createTableIfNotExists tab columns constraints = UnsafeDefinition $
214− "CREATE TABLE IF NOT EXISTS"
215− <+> renderCreation tab columns constraints
216−
217−-- helper function for `createTable` and `createTableIfNotExists`
218−renderCreation
219− :: ( KnownSymbol sch
220− , KnownSymbol tab
221− , SOP.SListI columns
222− , SOP.SListI constraints )
223− => QualifiedAlias sch tab -- ^ the name of the table to add
224− -> NP (Aliased (ColumnTypeExpression schemas0)) columns
225− -- ^ the names and datatype of each column
226− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
227− -- ^ constraints that must hold for the table
228− -> ByteString
229−renderCreation tab columns constraints = renderSQL tab
230− <+> parenthesized
231− ( renderCommaSeparated renderColumnDef columns
232− <> ( case constraints of
233− Nil -> ""
234− _ -> ", " <>
235− renderCommaSeparated renderConstraint constraints ) )
236− <> ";"
237− where
238− renderColumnDef :: Aliased (ColumnTypeExpression schemas) x -> ByteString
239− renderColumnDef (ty `As` column) =
240− renderSQL column <+> renderColumnTypeExpression ty
241− renderConstraint
242− :: Aliased (TableConstraintExpression sch tab schemas) constraint
243− -> ByteString
244− renderConstraint (constraint `As` alias) =
245− "CONSTRAINT" <+> renderSQL alias <+> renderSQL constraint
246−
247−-- | Data types are a way to limit the kind of data that can be stored in a
248−-- table. For many applications, however, the constraint they provide is
249−-- too coarse. For example, a column containing a product price should
250−-- probably only accept positive values. But there is no standard data type
251−-- that accepts only positive numbers. Another issue is that you might want
252−-- to constrain column data with respect to other columns or rows.
253−-- For example, in a table containing product information,
254−-- there should be only one row for each product number.
255−-- `TableConstraint`s give you as much control over the data in your tables
256−-- as you wish. If a user attempts to store data in a column that would
257−-- violate a constraint, an error is raised. This applies
258−-- even if the value came from the default value definition.
259−newtype TableConstraintExpression
260− (sch :: Symbol)
261− (tab :: Symbol)
262− (schemas :: SchemasType)
263− (constraint :: TableConstraint)
264− = UnsafeTableConstraintExpression
265− { renderTableConstraintExpression :: ByteString }
266− deriving (GHC.Generic,Show,Eq,Ord,NFData)
267−instance RenderSQL
268− (TableConstraintExpression sch tab schemas constraint) where
269− renderSQL = renderTableConstraintExpression
270−
271−{-| A `check` constraint is the most generic `TableConstraint` type.
272−It allows you to specify that the value in a certain column must satisfy
273−a Boolean (truth-value) expression.
274−
275−>>> :{
276−type Schema = '[
277− "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[
278− "a" ::: 'NoDef :=> 'NotNull 'PGint4,
279− "b" ::: 'NoDef :=> 'NotNull 'PGint4
280− ])]
281−:}
282−
283−>>> :{
284−let
285− definition :: Definition (Public '[]) (Public Schema)
286− definition = createTable #tab
287− ( (int & notNullable) `as` #a :*
288− (int & notNullable) `as` #b )
289− ( check (#a :* #b) (#a .> #b) `as` #inequality )
290−:}
291−
292−>>> printSQL definition
293−CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));
294−-}
295−check
296− :: ( Has sch schemas schema
297− , Has tab schema ('Table table)
298− , HasAll aliases (TableToRow table) subcolumns )
299− => NP Alias aliases
300− -- ^ specify the subcolumns which are getting checked
301− -> (forall t. Condition '[] 'Ungrouped '[] schemas '[] '[t ::: subcolumns])
302− -- ^ a closed `Condition` on those subcolumns
303− -> TableConstraintExpression sch tab schemas ('Check aliases)
304−check _cols condition = UnsafeTableConstraintExpression $
305− "CHECK" <+> parenthesized (renderSQL condition)
306−
307−{-| A `unique` constraint ensure that the data contained in a column,
308−or a group of columns, is unique among all the rows in the table.
309−
310−>>> :{
311−type Schema = '[
312− "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[
313− "a" ::: 'NoDef :=> 'Null 'PGint4,
314− "b" ::: 'NoDef :=> 'Null 'PGint4
315− ])]
316−:}
317−
318−>>> :{
319−let
320− definition :: Definition (Public '[]) (Public Schema)
321− definition = createTable #tab
322− ( (int & nullable) `as` #a :*
323− (int & nullable) `as` #b )
324− ( unique (#a :* #b) `as` #uq_a_b )
325−:}
326−
327−>>> printSQL definition
328−CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));
329−-}
330−unique
331− :: ( Has sch schemas schema
332− , Has tab schema('Table table)
333− , HasAll aliases (TableToRow table) subcolumns )
334− => NP Alias aliases
335− -- ^ specify subcolumns which together are unique for each row
336− -> TableConstraintExpression sch tab schemas ('Unique aliases)
337−unique columns = UnsafeTableConstraintExpression $
338− "UNIQUE" <+> parenthesized (renderSQL columns)
339−
340−{-| A `primaryKey` constraint indicates that a column, or group of columns,
341−can be used as a unique identifier for rows in the table.
342−This requires that the values be both unique and not null.
343−
344−>>> :{
345−type Schema = '[
346− "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[
347− "id" ::: 'Def :=> 'NotNull 'PGint4,
348− "name" ::: 'NoDef :=> 'NotNull 'PGtext
349− ])]
350−:}
351−
352−>>> :{
353−let
354− definition :: Definition (Public '[]) (Public Schema)
355− definition = createTable #tab
356− ( serial `as` #id :*
357− (text & notNullable) `as` #name )
358− ( primaryKey #id `as` #pk_id )
359−:}
360−
361−>>> printSQL definition
362−CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));
363−-}
364−primaryKey
365− :: ( Has sch schemas schema
366− , Has tab schema ('Table table)
367− , HasAll aliases (TableToColumns table) subcolumns
368− , AllNotNull subcolumns )
369− => NP Alias aliases
370− -- ^ specify the subcolumns which together form a primary key.
371− -> TableConstraintExpression sch tab schemas ('PrimaryKey aliases)
372−primaryKey columns = UnsafeTableConstraintExpression $
373− "PRIMARY KEY" <+> parenthesized (renderSQL columns)
374−
375−{-| A `foreignKey` specifies that the values in a column
376−(or a group of columns) must match the values appearing in some row of
377−another table. We say this maintains the referential integrity
378−between two related tables.
379−
380−>>> :{
381−type Schema =
382− '[ "users" ::: 'Table (
383− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
384− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
385− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
386− ])
387− , "emails" ::: 'Table (
388− '[ "pk_emails" ::: 'PrimaryKey '["id"]
389− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
390− ] :=>
391− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
392− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
393− , "email" ::: 'NoDef :=> 'Null 'PGtext
394− ])
395− ]
396−:}
397−
398−>>> :{
399−let
400− setup :: Definition (Public '[]) (Public Schema)
401− setup =
402− createTable #users
403− ( serial `as` #id :*
404− (text & notNullable) `as` #name )
405− ( primaryKey #id `as` #pk_users ) >>>
406− createTable #emails
407− ( serial `as` #id :*
408− (int & notNullable) `as` #user_id :*
409− (text & nullable) `as` #email )
410− ( primaryKey #id `as` #pk_emails :*
411− foreignKey #user_id #users #id
412− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
413−in printSQL setup
414−:}
415−CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
416−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);
417−
418−A `foreignKey` can even be a table self-reference.
419−
420−>>> :{
421−type Schema =
422− '[ "employees" ::: 'Table (
423− '[ "employees_pk" ::: 'PrimaryKey '["id"]
424− , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]
425− ] :=>
426− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
427− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
428− , "employer_id" ::: 'NoDef :=> 'Null 'PGint4
429− ])
430− ]
431−:}
432−
433−>>> :{
434−let
435− setup :: Definition (Public '[]) (Public Schema)
436− setup =
437− createTable #employees
438− ( serial `as` #id :*
439− (text & notNullable) `as` #name :*
440− (integer & nullable) `as` #employer_id )
441− ( primaryKey #id `as` #employees_pk :*
442− foreignKey #employer_id #employees #id
443− OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )
444−in printSQL setup
445−:}
446−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);
447−-}
448−foreignKey
449− :: (ForeignKeyed schemas sch schema child parent
450− table reftable
451− columns refcolumns
452− constraints cols
453− reftys tys )
454− => NP Alias columns
455− -- ^ column or columns in the table
456− -> Alias parent
457− -- ^ reference table
458− -> NP Alias refcolumns
459− -- ^ reference column or columns in the reference table
460− -> OnDeleteClause
461− -- ^ what to do when reference is deleted
462− -> OnUpdateClause
463− -- ^ what to do when reference is updated
464− -> TableConstraintExpression sch child schemas
465− ('ForeignKey columns parent refcolumns)
466−foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $
467− "FOREIGN KEY" <+> parenthesized (renderSQL keys)
468− <+> "REFERENCES" <+> renderSQL parent
469− <+> parenthesized (renderSQL refs)
470− <+> renderSQL ondel
471− <+> renderSQL onupd
472−
473−-- | A constraint synonym between types involved in a foreign key constraint.
474−type ForeignKeyed schemas
475− sch
476− schema
477− child parent
478− table reftable
479− columns refcolumns
480− constraints cols
481− reftys tys =
482− ( Has sch schemas schema
483− , Has child schema ('Table table)
484− , Has parent schema ('Table reftable)
485− , HasAll columns (TableToColumns table) tys
486− , reftable ~ (constraints :=> cols)
487− , HasAll refcolumns cols reftys
488− , SOP.AllZip SamePGType tys reftys
489− , Uniquely refcolumns constraints )
490−
491−-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.
492−data OnDeleteClause
493− = OnDeleteNoAction
494− -- ^ if any referencing rows still exist when the constraint is checked,
495− -- an error is raised
496− | OnDeleteRestrict -- ^ prevents deletion of a referenced row
497− | OnDeleteCascade
498− -- ^ specifies that when a referenced row is deleted,
499− -- row(s) referencing it should be automatically deleted as well
500− deriving (GHC.Generic,Show,Eq,Ord)
501−instance NFData OnDeleteClause
502−-- | Render `OnDeleteClause`.
503−instance RenderSQL OnDeleteClause where
504− renderSQL = \case
505− OnDeleteNoAction -> "ON DELETE NO ACTION"
506− OnDeleteRestrict -> "ON DELETE RESTRICT"
507− OnDeleteCascade -> "ON DELETE CASCADE"
508−
509−-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked
510−-- when a referenced column is changed (updated).
511−data OnUpdateClause
512− = OnUpdateNoAction
513− -- ^ if any referencing rows has not changed when the constraint is checked,
514− -- an error is raised
515− | OnUpdateRestrict -- ^ prevents update of a referenced row
516− | OnUpdateCascade
517− -- ^ the updated values of the referenced column(s) should be copied
518− -- into the referencing row(s)
519− deriving (GHC.Generic,Show,Eq,Ord)
520−instance NFData OnUpdateClause
521−
522−-- | Render `OnUpdateClause`.
523−instance RenderSQL OnUpdateClause where
524− renderSQL = \case
525− OnUpdateNoAction -> "ON UPDATE NO ACTION"
526− OnUpdateRestrict -> "ON UPDATE RESTRICT"
527− OnUpdateCascade -> "ON UPDATE CASCADE"
528−
529−{-----------------------------------------
530−DROP statements
531−-----------------------------------------}
532−
533−-- >>> :{
534−-- let
535−-- definition :: Definition '["muh_schema" ::: schema, "public" ::: public] '["public" ::: public]
536−-- definition = dropSchema #muh_schema
537−-- :}
538−--
539−-- >>> printSQL definition
540−-- DROP SCHEMA "muh_schema";
541−dropSchema
542− :: Has sch schemas schema
543− => Alias sch
544− -> Definition schemas (Drop sch schemas)
545−dropSchema sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"
546−
547−-- | `dropTable` removes a table from the schema.
548−--
549−-- >>> :{
550−-- let
551−-- definition :: Definition '["public" ::: '["muh_table" ::: 'Table t]] (Public '[])
552−-- definition = dropTable #muh_table
553−-- :}
554−--
555−-- >>> printSQL definition
556−-- DROP TABLE "muh_table";
557−dropTable
558− :: ( Has sch schemas schema
559− , Has tab schema ('Table table))
560− => QualifiedAlias sch tab -- ^ table to remove
561− -> Definition schemas (Alter sch (Drop tab schema) schemas)
562−dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderSQL tab <> ";"
563−
564−{-----------------------------------------
565−ALTER statements
566−-----------------------------------------}
567−
568−-- | `alterTable` changes the definition of a table from the schema.
569−alterTable
570− :: (Has sch schemas schema, Has tab schema ('Table table0))
571− => QualifiedAlias sch tab -- ^ table to alter
572− -> AlterTable sch tab schemas table1 -- ^ alteration to perform
573− -> Definition schemas (Alter sch (Alter tab ('Table table1) schema) schemas)
574−alterTable tab alteration = UnsafeDefinition $
575− "ALTER TABLE"
576− <+> renderSQL tab
577− <+> renderAlterTable alteration
578− <> ";"
579−
580−-- | `alterTableRename` changes the name of a table from the schema.
581−--
582−-- >>> printSQL $ alterTableRename #foo #bar
583−-- ALTER TABLE "foo" RENAME TO "bar";
584−alterTableRename
585− :: (KnownSymbol table0, KnownSymbol table1)
586− => Alias table0 -- ^ table to rename
587− -> Alias table1 -- ^ what to rename it
588− -> Definition schema (Rename table0 table1 schema)
589−alterTableRename table0 table1 = UnsafeDefinition $
590− "ALTER TABLE" <+> renderSQL table0
591− <+> "RENAME TO" <+> renderSQL table1 <> ";"
592−
593−-- | An `AlterTable` describes the alteration to perform on the columns
594−-- of a table.
595−newtype AlterTable
596− (sch :: Symbol)
597− (tab :: Symbol)
598− (schemas :: SchemasType)
599− (table :: TableType) =
600− UnsafeAlterTable {renderAlterTable :: ByteString}
601− deriving (GHC.Generic,Show,Eq,Ord,NFData)
602−
603−-- | An `addConstraint` adds a table constraint.
604−--
605−-- >>> :{
606−-- let
607−-- definition :: Definition
608−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
609−-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: 'Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
610−-- definition = alterTable #tab (addConstraint #positive (check #col (#col .> 0)))
611−-- in printSQL definition
612−-- :}
613−-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));
614−addConstraint
615− :: ( KnownSymbol alias
616− , Has sch schemas schema
617− , Has tab schema ('Table table0)
618− , table0 ~ (constraints :=> columns)
619− , table1 ~ (Create alias constraint constraints :=> columns) )
620− => Alias alias
621− -> TableConstraintExpression sch tab schemas constraint
622− -- ^ constraint to add
623− -> AlterTable sch tab schemas table1
624−addConstraint alias constraint = UnsafeAlterTable $
625− "ADD" <+> "CONSTRAINT" <+> renderSQL alias
626− <+> renderSQL constraint
627−
628−-- | A `dropConstraint` drops a table constraint.
629−--
630−-- >>> :{
631−-- let
632−-- definition :: Definition
633−-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
634−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
635−-- definition = alterTable #tab (dropConstraint #positive)
636−-- in printSQL definition
637−-- :}
638−-- ALTER TABLE "tab" DROP CONSTRAINT "positive";
639−dropConstraint
640− :: ( KnownSymbol constraint
641− , Has sch schemas schema
642− , Has tab schema ('Table table0)
643− , table0 ~ (constraints :=> columns)
644− , table1 ~ (Drop constraint constraints :=> columns) )
645− => Alias constraint
646− -- ^ constraint to drop
647− -> AlterTable sch tab schemas table1
648−dropConstraint constraint = UnsafeAlterTable $
649− "DROP" <+> "CONSTRAINT" <+> renderSQL constraint
650−
651−-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.
652−class AddColumn ty where
653− -- | `addColumn` adds a new column, initially filled with whatever
654− -- default value is given or with @NULL@.
655− --
656− -- >>> :{
657− -- let
658− -- definition :: Definition
659− -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
660− -- '["public" ::: '["tab" ::: 'Table ('[] :=>
661− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
662− -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]]
663− -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))
664− -- in printSQL definition
665− -- :}
666− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';
667− --
668− -- >>> :{
669− -- let
670− -- definition :: Definition
671− -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
672− -- '["public" ::: '["tab" ::: 'Table ('[] :=>
673− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
674− -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
675− -- definition = alterTable #tab (addColumn #col2 (text & nullable))
676− -- in printSQL definition
677− -- :}
678− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;
679− addColumn
680− :: ( KnownSymbol column
681− , Has sch schemas schema
682− , Has tab schema ('Table table0)
683− , table0 ~ (constraints :=> columns) )
684− => Alias column -- ^ column to add
685− -> ColumnTypeExpression schemas ty -- ^ type of the new column
686− -> AlterTable sch tab schemas (constraints :=> Create column ty columns)
687− addColumn column ty = UnsafeAlterTable $
688− "ADD COLUMN" <+> renderSQL column <+> renderColumnTypeExpression ty
689−instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)
690−instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)
691−
692−-- | A `dropColumn` removes a column. Whatever data was in the column
693−-- disappears. Table constraints involving the column are dropped, too.
694−-- However, if the column is referenced by a foreign key constraint of
695−-- another table, PostgreSQL will not silently drop that constraint.
696−--
697−-- >>> :{
698−-- let
699−-- definition :: Definition
700−-- '["public" ::: '["tab" ::: 'Table ('[] :=>
701−-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
702−-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
703−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
704−-- definition = alterTable #tab (dropColumn #col2)
705−-- in printSQL definition
706−-- :}
707−-- ALTER TABLE "tab" DROP COLUMN "col2";
708−dropColumn
709− :: ( KnownSymbol column
710− , Has sch schemas schema
711− , Has tab schema ('Table table0)
712− , table0 ~ (constraints :=> columns)
713− , table1 ~ (constraints :=> Drop column columns) )
714− => Alias column -- ^ column to remove
715− -> AlterTable sch tab schemas table1
716−dropColumn column = UnsafeAlterTable $
717− "DROP COLUMN" <+> renderSQL column
718−
719−-- | A `renameColumn` renames a column.
720−--
721−-- >>> :{
722−-- let
723−-- definition :: Definition
724−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]]
725−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]]
726−-- definition = alterTable #tab (renameColumn #foo #bar)
727−-- in printSQL definition
728−-- :}
729−-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";
730−renameColumn
731− :: ( KnownSymbol column0
732− , KnownSymbol column1
733− , Has sch schemas schema
734− , Has tab schema ('Table table0)
735− , table0 ~ (constraints :=> columns)
736− , table1 ~ (constraints :=> Rename column0 column1 columns) )
737− => Alias column0 -- ^ column to rename
738− -> Alias column1 -- ^ what to rename the column
739− -> AlterTable sch tab schemas table1
740−renameColumn column0 column1 = UnsafeAlterTable $
741− "RENAME COLUMN" <+> renderSQL column0 <+> "TO" <+> renderSQL column1
742−
743−-- | An `alterColumn` alters a single column.
744−alterColumn
745− :: ( KnownSymbol column
746− , Has sch schemas schema
747− , Has tab schema ('Table table0)
748− , table0 ~ (constraints :=> columns)
749− , Has column columns ty0
750− , table1 ~ (constraints :=> Alter column ty1 columns))
751− => Alias column -- ^ column to alter
752− -> AlterColumn schemas ty0 ty1 -- ^ alteration to perform
753− -> AlterTable sch tab schemas table1
754−alterColumn column alteration = UnsafeAlterTable $
755− "ALTER COLUMN" <+> renderSQL column <+> renderAlterColumn alteration
756−
757−-- | An `AlterColumn` describes the alteration to perform on a single column.
758−newtype AlterColumn (schemas :: SchemasType) (ty0 :: ColumnType) (ty1 :: ColumnType) =
759− UnsafeAlterColumn {renderAlterColumn :: ByteString}
760− deriving (GHC.Generic,Show,Eq,Ord,NFData)
761−
762−-- | A `setDefault` sets a new default for a column. Note that this doesn't
763−-- affect any existing rows in the table, it just changes the default for
764−-- future insert and update commands.
765−--
766−-- >>> :{
767−-- let
768−-- definition :: Definition
769−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
770−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
771−-- definition = alterTable #tab (alterColumn #col (setDefault 5))
772−-- in printSQL definition
773−-- :}
774−-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;
775−setDefault
776− :: Expression '[] 'Ungrouped '[] schemas '[] '[] ty -- ^ default value to set
777− -> AlterColumn schemas (constraint :=> ty) ('Def :=> ty)
778−setDefault expression = UnsafeAlterColumn $
779− "SET DEFAULT" <+> renderExpression expression
780−
781−-- | A `dropDefault` removes any default value for a column.
782−--
783−-- >>> :{
784−-- let
785−-- definition :: Definition
786−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
787−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
788−-- definition = alterTable #tab (alterColumn #col dropDefault)
789−-- in printSQL definition
790−-- :}
791−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;
792−dropDefault :: AlterColumn schemas ('Def :=> ty) ('NoDef :=> ty)
793−dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"
794−
795−-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.
796−-- The constraint will be checked immediately, so the table data must satisfy
797−-- the constraint before it can be added.
798−--
799−-- >>> :{
800−-- let
801−-- definition :: Definition
802−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
803−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
804−-- definition = alterTable #tab (alterColumn #col setNotNull)
805−-- in printSQL definition
806−-- :}
807−-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;
808−setNotNull
809− :: AlterColumn schemas (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)
810−setNotNull = UnsafeAlterColumn $ "SET NOT NULL"
811−
812−-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.
813−--
814−-- >>> :{
815−-- let
816−-- definition :: Definition
817−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
818−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
819−-- definition = alterTable #tab (alterColumn #col dropNotNull)
820−-- in printSQL definition
821−-- :}
822−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;
823−dropNotNull
824− :: AlterColumn schemas (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)
825−dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"
826−
827−-- | An `alterType` converts a column to a different data type.
828−-- This will succeed only if each existing entry in the column can be
829−-- converted to the new type by an implicit cast.
830−--
831−-- >>> :{
832−-- let
833−-- definition :: Definition
834−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
835−-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]]
836−-- definition =
837−-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))
838−-- in printSQL definition
839−-- :}
840−-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;
841−alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty
842−alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty
843−
844−{- | Create a view.
845−>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]
846−>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]
847−>>> :{
848−let
849− definition :: Definition
850− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]
851− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc" ::: 'View BC]]
852− definition =
853− createView #bc (select_ (#b :* #c) (from (table #abc)))
854−in printSQL definition
855−:}
856−CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";
857−-}
858−createView
859− :: (KnownSymbol sch, KnownSymbol vw, Has sch schemas schema)
860− => QualifiedAlias sch vw -- ^ the name of the view to add
861− -> Query '[] '[] schemas '[] view -- ^ query
862− -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)
863−createView alias query = UnsafeDefinition $
864− "CREATE" <+> "VIEW" <+> renderSQL alias <+> "AS"
865− <+> renderQuery query <> ";"
866−
867−-- | Drop a view.
868−--
869−-- >>> :{
870−-- let
871−-- definition :: Definition
872−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
873−-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]
874−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]
875−-- definition = dropView #bc
876−-- in printSQL definition
877−-- :}
878−-- DROP VIEW "bc";
879−dropView
880− :: (Has sch schemas schema, Has vw schema ('View view))
881− => QualifiedAlias sch vw -- ^ view to remove
882− -> Definition schemas (Alter sch (Drop vw schema) schemas)
883−dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderSQL vw <> ";"
884−
885−-- | Enumerated types are created using the `createTypeEnum` command, for example
886−--
887−-- >>> printSQL $ (createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy") :: Definition (Public '[]) '["public" ::: '["mood" ::: 'Typedef ('PGenum '["sad","ok","happy"])]])
888−-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');
889−createTypeEnum
890− :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)
891− => QualifiedAlias sch enum
892− -- ^ name of the user defined enumerated type
893− -> NP PGlabel labels
894− -- ^ labels of the enumerated type
895− -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)
896−createTypeEnum enum labels = UnsafeDefinition $
897− "CREATE" <+> "TYPE" <+> renderSQL enum <+> "AS" <+> "ENUM" <+>
898− parenthesized (renderSQL labels) <> ";"
899−
900−-- | Enumerated types can also be generated from a Haskell type, for example
901−--
902−-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
903−-- >>> instance SOP.Generic Schwarma
904−-- >>> instance SOP.HasDatatypeInfo Schwarma
905−-- >>> :{
906−-- let
907−-- createSchwarma :: Definition (Public '[]) '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]]
908−-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma
909−-- in
910−-- printSQL createSchwarma
911−-- :}
912−-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');
913−createTypeEnumFrom
914− :: forall hask sch enum schemas schema.
915− ( SOP.Generic hask
916− , SOP.All KnownSymbol (LabelsPG hask)
917− , KnownSymbol enum
918− , Has sch schemas schema )
919− => QualifiedAlias sch enum
920− -- ^ name of the user defined enumerated type
921− -> Definition schemas (Alter sch (Create enum ('Typedef (PG (Enumerated hask))) schema) schemas)
922−createTypeEnumFrom enum = createTypeEnum enum
923− (SOP.hpure label :: NP PGlabel (LabelsPG hask))
924−
925−{- | `createTypeComposite` creates a composite type. The composite type is
926−specified by a list of attribute names and data types.
927−
928−>>> :{
929−type PGcomplex = 'PGcomposite
930− '[ "real" ::: 'NotNull 'PGfloat8
931− , "imaginary" ::: 'NotNull 'PGfloat8 ]
932−:}
933−
934−>>> :{
935−let
936− setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]
937− setup = createTypeComposite #complex
938− (float8 `as` #real :* float8 `as` #imaginary)
939−in printSQL setup
940−:}
941−CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
942−-}
943−createTypeComposite
944− :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)
945− => QualifiedAlias sch ty
946− -- ^ name of the user defined composite type
947− -> NP (Aliased (TypeExpression schemas)) fields
948− -- ^ list of attribute names and data types
949− -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)
950−createTypeComposite ty fields = UnsafeDefinition $
951− "CREATE" <+> "TYPE" <+> renderSQL ty <+> "AS" <+> parenthesized
952− (renderCommaSeparated renderField fields) <> ";"
953− where
954− renderField :: Aliased (TypeExpression schemas) x -> ByteString
955− renderField (typ `As` alias) =
956− renderSQL alias <+> renderSQL typ
957−
958−-- | Composite types can also be generated from a Haskell type, for example
959−--
960−-- >>> data Complex = Complex {real :: Double, imaginary :: Double} deriving GHC.Generic
961−-- >>> instance SOP.Generic Complex
962−-- >>> instance SOP.HasDatatypeInfo Complex
963−-- >>> type Schema = '["complex" ::: 'Typedef (PG (Composite Complex))]
964−-- >>> :{
965−-- let
966−-- createComplex :: Definition (Public '[]) (Public Schema)
967−-- createComplex = createTypeCompositeFrom @Complex #complex
968−-- in
969−-- printSQL createComplex
970−-- :}
971−-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
972−createTypeCompositeFrom
973− :: forall hask sch ty schemas schema.
974− ( SOP.All (FieldTyped schemas) (RowPG hask)
975− , KnownSymbol ty
976− , Has sch schemas schema )
977− => QualifiedAlias sch ty
978− -- ^ name of the user defined composite type
979− -> Definition schemas (Alter sch (Create ty ( 'Typedef (PG (Composite hask))) schema) schemas)
980−createTypeCompositeFrom ty = createTypeComposite ty
981− (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype
982− :: NP (Aliased (TypeExpression schemas)) (RowPG hask))
983−
984−{-|
985−`createDomain` creates a new domain. A domain is essentially a data type
986−with constraints (restrictions on the allowed set of values).
987−
988−Domains are useful for abstracting common constraints on fields
989−into a single location for maintenance. For example, several tables might
990−contain email address columns, all requiring the same `check` constraint
991−to verify the address syntax. Define a domain rather than setting up
992−each table's constraint individually.
993−
994−>>> :{
995−let
996− createPositive :: Definition (Public '[]) (Public '["positive" ::: 'Typedef 'PGfloat4])
997− createPositive = createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
998−in printSQL createPositive
999−:}
1000−CREATE DOMAIN "positive" AS real CHECK ((("value" > 0) AND "value" IS NOT NULL));
1001−-}
1002−createDomain
1003− :: (Has sch schemas schema, KnownSymbol dom)
1004− => QualifiedAlias sch dom
1005− -> (forall nullity. TypeExpression schemas (nullity ty))
1006− -> (forall tab. Condition '[] 'Ungrouped '[] schemas '[] '[tab ::: '["value" ::: 'Null ty]])
1007− -> Definition schemas (Alter sch (Create alias ('Typedef ty) schema) schemas)
1008−createDomain dom ty condition =
1009− UnsafeDefinition $ "CREATE DOMAIN" <+> renderSQL dom
1010− <+> "AS" <+> renderTypeExpression ty
1011− <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"
1012−
1013−class FieldTyped schemas ty where
1014− fieldtype :: Aliased (TypeExpression schemas) ty
1015−instance (KnownSymbol alias, PGTyped schemas ty)
1016− => FieldTyped schemas (alias ::: ty) where
1017− fieldtype = pgtype `As` Alias
1018−
1019−-- | Drop a type.
1020−--
1021−-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
1022−-- >>> instance SOP.Generic Schwarma
1023−-- >>> instance SOP.HasDatatypeInfo Schwarma
1024−-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))
1025−-- DROP TYPE "schwarma";
1026−dropType
1027− :: (Has sch schemas schema, Has td schema ('Typedef ty))
1028− => QualifiedAlias sch td
1029− -- ^ name of the user defined type
1030− -> Definition schemas (Alter sch (Drop td schema) schemas)
1031−dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"
1032−
1033−-- | `ColumnTypeExpression`s are used in `createTable` commands.
1034−newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)
1035− = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }
1036− deriving (GHC.Generic,Show,Eq,Ord,NFData)
1037−instance RenderSQL (ColumnTypeExpression schemas ty) where
1038− renderSQL = renderColumnTypeExpression
1039−
1040−-- | used in `createTable` commands as a column constraint to note that
1041−-- @NULL@ may be present in a column
1042−nullable
1043− :: TypeExpression schemas (nullity ty)
1044− -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)
1045−nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"
1046−
1047−-- | used in `createTable` commands as a column constraint to ensure
1048−-- @NULL@ is not present in a column
1049−notNullable
1050− :: TypeExpression schemas (nullity ty)
1051− -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)
1052−notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"
1053−
1054−-- | used in `createTable` commands as a column constraint to give a default
1055−default_
1056− :: Expression '[] 'Ungrouped '[] schemas '[] '[] ty
1057− -> ColumnTypeExpression schemas ('NoDef :=> ty)
1058− -> ColumnTypeExpression schemas ('Def :=> ty)
1059−default_ x ty = UnsafeColumnTypeExpression $
1060− renderSQL ty <+> "DEFAULT" <+> renderExpression x
1061−
1062−-- | not a true type, but merely a notational convenience for creating
1063−-- unique identifier columns with type `PGint2`
1064−serial2, smallserial
1065− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)
1066−serial2 = UnsafeColumnTypeExpression "serial2"
1067−smallserial = UnsafeColumnTypeExpression "smallserial"
1068−-- | not a true type, but merely a notational convenience for creating
1069−-- unique identifier columns with type `PGint4`
1070−serial4, serial
1071− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)
1072−serial4 = UnsafeColumnTypeExpression "serial4"
1073−serial = UnsafeColumnTypeExpression "serial"
1074−-- | not a true type, but merely a notational convenience for creating
1075−-- unique identifier columns with type `PGint8`
1076−serial8, bigserial
1077− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)
1078−serial8 = UnsafeColumnTypeExpression "serial8"
1079−bigserial = UnsafeColumnTypeExpression "bigserial"
82+manipDefinition = UnsafeDefinition . (<> ";") . renderSQL
squeal-postgresql/src/Squeal/PostgreSQL/Definition/Function.hsnew file+238
@@ -0,0 +1,238 @@
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.hsnew file+159
@@ -0,0 +1,159 @@
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.hsnew file+96
@@ -0,0 +1,96 @@
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.hsnew file+500
@@ -0,0 +1,500 @@
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.hsnew file+339
@@ -0,0 +1,339 @@
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.hsnew file+229
@@ -0,0 +1,229 @@
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.hsnew file+104
@@ -0,0 +1,104 @@
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+242−2196
@@ -1,14 +1,13 @@
11{-|
22Module: Squeal.PostgreSQL.Expression
33Description: Squeal expressions
4−Copyright: (c) Eitan Chatav, 2017
4+Copyright: (c) Eitan Chatav, 2019
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 #-}
1211{-# LANGUAGE
1312 AllowAmbiguousTypes
1413 , ConstraintKinds
@@ -34,298 +33,214 @@ Squeal expressions are the atoms used to build statements.
3433module Squeal.PostgreSQL.Expression
3534 ( -- * Expression
3635 Expression (..)
37− , HasParameter (parameter)
38− , param
39− -- ** Null
40− , null_
41− , notNull
42− , coalesce
43− , fromNull
44− , isNull
45− , isNotNull
46− , matchNull
47− , nullIf
48− -- ** Collections
49− , array
50− , cardinality
51− , index
52− , row
53− , field
54− -- ** Functions
55− , unsafeBinaryOp
56− , unsafeUnaryOp
36+ , Expr
37+ , type (-->)
38+ , FunctionDB
5739 , unsafeFunction
58− , unsafeVariadicFunction
59− , atan2_
60− , cast
61− , quot_
62− , rem_
63− , trunc
64− , round_
65− , ceiling_
66− , greatest
67− , least
68− -- ** Conditions
69− , true
70− , false
71− , not_
72− , (.&&)
73− , (.||)
74− , Condition
75− , caseWhenThenElse
76− , ifThenElse
77− , (.==)
78− , (./=)
79− , (.>=)
80− , (.<)
81− , (.<=)
82− , (.>)
83− -- ** Time
84− , currentDate
85− , currentTime
86− , currentTimestamp
87− , localTime
88− , localTimestamp
89− , TimeOp (..)
90− , makeDate
91− , makeTime
92− , makeTimestamp
93− , makeTimestamptz
94− -- ** Text
95− , lower
96− , upper
97− , charLength
98− , like
99− , ilike
100− -- ** Json
101− -- *** Json and Jsonb operators
102− , (.->)
103− , (.->>)
104− , (.#>)
105− , (.#>>)
106− -- *** Jsonb operators
107− , (.@>)
108− , (.<@)
109− , (.?)
110− , (.?|)
111− , (.?&)
112− , (.-.)
113− , (#-.)
114− -- *** Functions
115− , jsonLit
116− , jsonbLit
117− , toJson
118− , toJsonb
119− , arrayToJson
120− , rowToJson
121− , jsonBuildArray
122− , jsonbBuildArray
123− , jsonBuildObject
124− , jsonbBuildObject
125− , jsonObject
126− , jsonbObject
127− , jsonZipObject
128− , jsonbZipObject
129− , jsonArrayLength
130− , jsonbArrayLength
131− , jsonExtractPath
132− , jsonbExtractPath
133− , jsonExtractPathAsText
134− , jsonbExtractPathAsText
135− , jsonTypeof
136− , jsonbTypeof
137− , jsonStripNulls
138− , jsonbStripNulls
139− , jsonbSet
140− , jsonbInsert
141− , jsonbPretty
142− -- ** Aggregation
143− , Aggregate (..)
144− , Distinction (..)
145− , PGAvg
146− -- * Window Functions
147− , WindowDefinition (..)
148− , partitionBy
149− , WindowFunction (..)
150− , rank
151− , rowNumber
152− , denseRank
153− , percentRank
154− , cumeDist
155− , ntile
156− , lag
157− , lead
158− , firstValue
159− , lastValue
160− , nthValue
161− -- * Sorting
162− , SortExpression (..)
163− , OrderBy (..)
164− -- * Types
165− , TypeExpression (..)
166− , PGTyped (..)
167− , typedef
168− , typetable
169− , typeview
170− , bool
171− , int2
172− , smallint
173− , int4
174− , int
175− , integer
176− , int8
177− , bigint
178− , numeric
179− , float4
180− , real
181− , float8
182− , doublePrecision
183− , money
184− , text
185− , char
186− , character
187− , varchar
188− , characterVarying
189− , bytea
190− , timestamp
191− , timestampWithTimeZone
192− , date
193− , time
194− , timeWithTimeZone
195− , interval
196− , uuid
197− , inet
198− , json
199− , jsonb
200− , vararray
201− , fixarray
40+ , function
41+ , unsafeLeftOp
42+ , leftOp
43+ , unsafeRightOp
44+ , rightOp
45+ , Operator
46+ , OperatorDB
47+ , unsafeBinaryOp
48+ , binaryOp
49+ , FunctionVar
50+ , unsafeFunctionVar
51+ , type (--->)
52+ , FunctionNDB
53+ , unsafeFunctionN
54+ , functionN
55+ , PGSubset (..)
56+ , PGIntersect (..)
20257 -- * Re-export
20358 , (&)
204− , NP (..)
205− , (:*:) (..)
20659 , K (..)
60+ , unK
20761 ) where
20862
20963import Control.Category
21064import Control.DeepSeq
21165import Data.ByteString (ByteString)
212−import Data.ByteString.Lazy (toStrict)
21366import Data.Function ((&))
21467import Data.Semigroup hiding (All)
215−import qualified Data.Aeson as JSON
21668import Data.String
217−import Data.Word
21869import Generics.SOP hiding (All, from)
219−import GHC.Generics ((:*:) (..))
22070import GHC.OverloadedLabels
22171import GHC.TypeLits
22272import Numeric
22373import Prelude hiding (id, (.))
22474
225−import qualified Data.ByteString as ByteString
22675import qualified GHC.Generics as GHC
227−import qualified Generics.SOP as SOP
22876
77+import Squeal.PostgreSQL.Alias
78+import Squeal.PostgreSQL.List
22979import Squeal.PostgreSQL.Render
23080import Squeal.PostgreSQL.Schema
23181
82+-- $setup
83+-- >>> import Squeal.PostgreSQL
84+
23285{-----------------------------------------
23386column expressions
23487-----------------------------------------}
23588
23689{- | `Expression`s are used in a variety of contexts,
237−such as in the target list of the `Squeal.PostgreSQL.Query.select` command,
90+such as in the target `Squeal.PostgreSQL.Query.List` of the
91+`Squeal.PostgreSQL.Query.select` command,
23892as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or
23993`Squeal.PostgreSQL.Manipulation.update`,
240−or in search `Condition`s in a number of commands.
94+or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.
24195
24296The expression syntax allows the calculation of
24397values from primitive expression using arithmetic, logical,
24498and 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`.
245113-}
246114newtype Expression
247115 (outer :: FromType)
248− (grp :: Grouping)
249116 (commons :: FromType)
117+ (grp :: Grouping)
250118 (schemas :: SchemasType)
251119 (params :: [NullityType])
252120 (from :: FromType)
253121 (ty :: NullityType)
254122 = UnsafeExpression { renderExpression :: ByteString }
255123 deriving (GHC.Generic,Show,Eq,Ord,NFData)
256−
257−instance RenderSQL (Expression outer grp commons schemas params from ty) where
124+instance RenderSQL (Expression outer commons grp schemas params from ty) where
258125 renderSQL = renderExpression
259126
260−{- | A `HasParameter` constraint is used to indicate a value that is
261−supplied externally to a SQL statement.
262−`Squeal.PostgreSQL.PQ.manipulateParams`,
263−`Squeal.PostgreSQL.PQ.queryParams` and
264−`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values
265−separately from the SQL command string, in which case `param`s are used to
266−refer to the out-of-line data values.
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)
267181-}
268−class KnownNat n => HasParameter
269− (n :: Nat)
270− (params :: [NullityType])
271− (ty :: NullityType)
272− | n params -> ty where
273− -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.
274− --
275− -- >>> let expr = parameter @1 int4 :: Expression outer grp '[] schemas '[ 'Null 'PGint4] from ('Null 'PGint4)
276− -- >>> printSQL expr
277− -- ($1 :: int4)
278− parameter
279− :: TypeExpression schemas ty
280− -> Expression outer grp commons schemas params from ty
281− parameter ty = UnsafeExpression $ parenthesized $
282− "$" <> renderNat @n <+> "::"
283− <+> renderSQL ty
284−instance {-# OVERLAPPING #-} HasParameter 1 (ty1:tys) ty1
285−instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)
286− => HasParameter n (ty' : params) ty
287−
288−-- | `param` takes a `Nat` using type application and for basic types,
289−-- infers a `TypeExpression`.
290−--
291−-- >>> let expr = param @1 :: Expression outer grp commons schemas '[ 'Null 'PGint4] from ('Null 'PGint4)
292−-- >>> printSQL expr
293−-- ($1 :: int4)
294−param
295− :: forall n outer commons schemas params from grp ty
296− . (PGTyped schemas ty, HasParameter n params ty)
297− => Expression outer grp commons schemas params from ty -- ^ param
298−param = parameter @n (pgtype @schemas)
182+type (--->) xs y
183+ = forall outer commons grp schemas params from
184+ . NP (Expression outer commons grp schemas params from) xs
185+ -- ^ inputs
186+ -> Expression outer commons grp schemas params from y
187+ -- ^ output
188+
189+type FunctionNDB schemas xs y
190+ = forall outer commons grp params from
191+ . NP (Expression outer commons grp schemas params from) xs
192+ -- ^ inputs
193+ -> Expression outer commons grp schemas params from y
194+ -- ^ output
195+
196+{- | A @RankNType@ for functions with a variable-length list of
197+homogeneous arguments and at least 1 more argument.
198+-}
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)
299214
300215instance (HasUnique tab (Join outer from) row, Has col row ty)
301− => IsLabel col (Expression outer 'Ungrouped commons schemas params from ty) where
216+ => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where
302217 fromLabel = UnsafeExpression $ renderSQL (Alias @col)
303218instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])
304− => IsLabel col (NP (Expression outer 'Ungrouped commons schemas params from) tys) where
219+ => IsLabel col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
305220 fromLabel = fromLabel @col :* Nil
306221instance (HasUnique tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
307222 => IsLabel col
308− (Aliased (Expression outer 'Ungrouped commons schemas params from) column) where
223+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
309224 fromLabel = fromLabel @col `As` Alias
310225instance (HasUnique tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
311226 => IsLabel col
312− (NP (Aliased (Expression outer 'Ungrouped commons schemas params from)) columns) where
227+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
313228 fromLabel = fromLabel @col :* Nil
314229
315230instance (Has tab (Join outer from) row, Has col row ty)
316− => IsQualified tab col (Expression outer 'Ungrouped commons schemas params from ty) where
231+ => IsQualified tab col (Expression outer commons 'Ungrouped schemas params from ty) where
317232 tab ! col = UnsafeExpression $
318233 renderSQL tab <> "." <> renderSQL col
319234instance (Has tab (Join outer from) row, Has col row ty, tys ~ '[ty])
320− => IsQualified tab col (NP (Expression outer 'Ungrouped commons schemas params from) tys) where
235+ => IsQualified tab col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where
321236 tab ! col = tab ! col :* Nil
322237instance (Has tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))
323238 => IsQualified tab col
324− (Aliased (Expression outer 'Ungrouped commons schemas params from) column) where
239+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where
325240 tab ! col = tab ! col `As` col
326241instance (Has tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])
327242 => IsQualified tab col
328− (NP (Aliased (Expression outer 'Ungrouped commons schemas params from)) columns) where
243+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where
329244 tab ! col = tab ! col :* Nil
330245
331246instance
@@ -333,7 +248,7 @@ instance
333248 , Has col row ty
334249 , GroupedBy tab col bys
335250 ) => IsLabel col
336− (Expression outer ('Grouped bys) commons schemas params from ty) where
251+ (Expression outer commons ('Grouped bys) schemas params from ty) where
337252 fromLabel = UnsafeExpression $ renderSQL (Alias @col)
338253instance
339254 ( HasUnique tab (Join outer from) row
@@ -341,7 +256,7 @@ instance
341256 , GroupedBy tab col bys
342257 , tys ~ '[ty]
343258 ) => IsLabel col
344− (NP (Expression outer ('Grouped bys) commons schemas params from) tys) where
259+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where
345260 fromLabel = fromLabel @col :* Nil
346261instance
347262 ( HasUnique tab (Join outer from) row
@@ -349,7 +264,7 @@ instance
349264 , GroupedBy tab col bys
350265 , column ~ (col ::: ty)
351266 ) => IsLabel col
352− (Aliased (Expression outer ('Grouped bys) commons schemas params from) column) where
267+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
353268 fromLabel = fromLabel @col `As` Alias
354269instance
355270 ( HasUnique tab (Join outer from) row
@@ -357,7 +272,7 @@ instance
357272 , GroupedBy tab col bys
358273 , columns ~ '[col ::: ty]
359274 ) => IsLabel col
360− (NP (Aliased (Expression outer ('Grouped bys) commons schemas params from)) columns) where
275+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
361276 fromLabel = fromLabel @col :* Nil
362277
363278instance
@@ -365,7 +280,7 @@ instance
365280 , Has col row ty
366281 , GroupedBy tab col bys
367282 ) => IsQualified tab col
368− (Expression outer ('Grouped bys) commons schemas params from ty) where
283+ (Expression outer commons ('Grouped bys) schemas params from ty) where
369284 tab ! col = UnsafeExpression $
370285 renderSQL tab <> "." <> renderSQL col
371286instance
@@ -374,7 +289,7 @@ instance
374289 , GroupedBy tab col bys
375290 , tys ~ '[ty]
376291 ) => IsQualified tab col
377− (NP (Expression outer ('Grouped bys) commons schemas params from) tys) where
292+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where
378293 tab ! col = tab ! col :* Nil
379294instance
380295 ( Has tab (Join outer from) row
@@ -382,7 +297,7 @@ instance
382297 , GroupedBy tab col bys
383298 , column ~ (col ::: ty)
384299 ) => IsQualified tab col
385− (Aliased (Expression outer ('Grouped bys) commons schemas params from) column) where
300+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where
386301 tab ! col = tab ! col `As` col
387302instance
388303 ( Has tab (Join outer from) row
@@ -390,244 +305,78 @@ instance
390305 , GroupedBy tab col bys
391306 , columns ~ '[col ::: ty]
392307 ) => IsQualified tab col
393− (NP (Aliased (Expression outer ('Grouped bys) commons schemas params from)) columns) where
308+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where
394309 tab ! col = tab ! col :* Nil
395310
396−-- | analagous to `Nothing`
397−--
398−-- >>> printSQL null_
399−-- NULL
400−null_ :: Expression outer grp commons schemas params from ('Null ty)
401−null_ = UnsafeExpression "NULL"
402−
403−-- | analagous to `Just`
404−--
405−-- >>> printSQL $ notNull true
406−-- TRUE
407−notNull
408− :: Expression outer grp commons schemas params from ('NotNull ty)
409− -> Expression outer grp commons schemas params from ('Null ty)
410−notNull = UnsafeExpression . renderSQL
411−
412−-- | return the leftmost value which is not NULL
413−--
414−-- >>> printSQL $ coalesce [null_, true] false
415−-- COALESCE(NULL, TRUE, FALSE)
416−coalesce
417− :: [Expression outer grp commons schemas params from ('Null ty)]
418− -- ^ @NULL@s may be present
419− -> Expression outer grp commons schemas params from ('NotNull ty)
420− -- ^ @NULL@ is absent
421− -> Expression outer grp commons schemas params from ('NotNull ty)
422−coalesce nullxs notNullx = UnsafeExpression $
423− "COALESCE" <> parenthesized (commaSeparated
424− ((renderSQL <$> nullxs) <> [renderSQL notNullx]))
425−
426−-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@
427−--
428−-- >>> printSQL $ fromNull true null_
429−-- COALESCE(NULL, TRUE)
430−fromNull
431− :: Expression outer grp commons schemas params from ('NotNull ty)
432− -- ^ what to convert @NULL@ to
433− -> Expression outer grp commons schemas params from ('Null ty)
434− -> Expression outer grp commons schemas params from ('NotNull ty)
435−fromNull notNullx nullx = coalesce [nullx] notNullx
436−
437−-- | >>> printSQL $ null_ & isNull
438−-- NULL IS NULL
439−isNull
440− :: Expression outer grp commons schemas params from ('Null ty)
441− -- ^ possibly @NULL@
442− -> Condition outer grp commons schemas params from
443−isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"
444−
445−-- | >>> printSQL $ null_ & isNotNull
446−-- NULL IS NOT NULL
447−isNotNull
448− :: Expression outer grp commons schemas params from ('Null ty)
449− -- ^ possibly @NULL@
450− -> Condition outer grp commons schemas params from
451−isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"
452−
453−-- | analagous to `maybe` using @IS NULL@
454−--
455−-- >>> printSQL $ matchNull true not_ null_
456−-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END
457−matchNull
458− :: Expression outer grp commons schemas params from (nullty)
459− -- ^ what to convert @NULL@ to
460− -> ( Expression outer grp commons schemas params from ('NotNull ty)
461− -> Expression outer grp commons schemas params from (nullty) )
462− -- ^ function to perform when @NULL@ is absent
463− -> Expression outer grp commons schemas params from ('Null ty)
464− -> Expression outer grp commons schemas params from (nullty)
465−matchNull y f x = ifThenElse (isNull x) y
466− (f (UnsafeExpression (renderSQL x)))
467−
468−{-| right inverse to `fromNull`, if its arguments are equal then
469−`nullIf` gives @NULL@.
470−
471−>>> :set -XTypeApplications -XDataKinds
472−>>> let expr = nullIf false (param @1) :: Expression outer grp commons schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)
473−>>> printSQL expr
474−NULL IF (FALSE, ($1 :: bool))
475−-}
476−nullIf
477− :: Expression outer grp commons schemas params from ('NotNull ty)
478− -- ^ @NULL@ is absent
479− -> Expression outer grp commons schemas params from ('NotNull ty)
480− -- ^ @NULL@ is absent
481− -> Expression outer grp commons schemas params from ('Null ty)
482−nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized
483− (renderSQL x <> ", " <> renderSQL y)
484−
485−-- | >>> printSQL $ array [null_, false, true]
486−-- ARRAY[NULL, FALSE, TRUE]
487−array
488− :: [Expression outer grp commons schemas params from ty]
489− -- ^ array elements
490− -> Expression outer grp commons schemas params from (nullity ('PGvararray ty))
491−array xs = UnsafeExpression $
492− "ARRAY[" <> commaSeparated (renderSQL <$> xs) <> "]"
493−
494−-- | >>> printSQL $ cardinality (array [null_, false, true])
495−-- cardinality(ARRAY[NULL, FALSE, TRUE])
496−cardinality
497− :: Expression outer grp commons schemas params from (nullity ('PGvararray ty))
498− -> Expression outer grp commons schemas params from (nullity 'PGint8)
499−cardinality = unsafeFunction "cardinality"
500−
501−-- | >>> printSQL $ array [null_, false, true] & index 2
502−-- (ARRAY[NULL, FALSE, TRUE])[2]
503−index
504− :: Word64 -- ^ index
505− -> Expression outer grp commons schemas params from (nullity ('PGvararray ty)) -- ^ array
506− -> Expression outer grp commons schemas params from (NullifyType ty)
507−index n expr = UnsafeExpression $
508− parenthesized (renderSQL expr) <> "[" <> fromString (show n) <> "]"
509−
510311instance (KnownSymbol label, label `In` labels) => IsPGlabel label
511− (Expression outer grp commons schemas params from (nullity ('PGenum labels))) where
312+ (Expression outer commons grp schemas params from (null ('PGenum labels))) where
512313 label = UnsafeExpression $ renderSQL (PGlabel @label)
513314
514−-- | A row constructor is an expression that builds a row value
515−-- (also called a composite value) using values for its member fields.
516−--
517−-- >>> :{
518−-- type Complex = 'PGcomposite
519−-- '[ "real" ::: 'NotNull 'PGfloat8
520−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]
521−-- :}
522−--
523−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer grp commons schemas params from ('NotNull Complex)
524−-- >>> printSQL i
525−-- ROW(0, 1)
526−row
527− :: SListI row
528− => NP (Aliased (Expression outer grp commons schemas params from)) row
529− -- ^ zero or more expressions for the row field values
530− -> Expression outer grp commons schemas params from (nullity ('PGcomposite row))
531−row exprs = UnsafeExpression $ "ROW" <> parenthesized
532− (renderCommaSeparated (\ (expr `As` _) -> renderSQL expr) exprs)
533−
534−-- | >>> :{
535−-- type Complex = 'PGcomposite
536−-- '[ "real" ::: 'NotNull 'PGfloat8
537−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]
538−-- type Schema = '["complex" ::: 'Typedef Complex]
539−-- :}
540−--
541−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer grp '[] (Public Schema) from params ('NotNull Complex)
542−-- >>> printSQL $ i & field #complex #imaginary
543−-- (ROW(0, 1)::"complex")."imaginary"
544−field
545− :: ( Has sch schemas schema
546− , Has tydef schema ('Typedef ('PGcomposite row))
547− , Has field row ty)
548− => QualifiedAlias sch tydef -- ^ row type
549− -> Alias field -- ^ field name
550− -> Expression outer grp commons schemas params from ('NotNull ('PGcomposite row))
551− -> Expression outer grp commons schemas params from ty
552−field td fld expr = UnsafeExpression $
553− parenthesized (renderSQL expr <> "::" <> renderSQL td)
554− <> "." <> renderSQL fld
555−
556−instance Semigroup
557− (Expression outer grp commons schemas params from (nullity ('PGvararray ty))) where
558− (<>) = unsafeBinaryOp "||"
559−
560−instance Monoid
561− (Expression outer grp commons schemas params from (nullity ('PGvararray ty))) where
562− mempty = array []
563− mappend = (<>)
564−
565−-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression outer grp commons schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)
566−-- >>> printSQL expr
567−-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))
568−greatest
569− :: Expression outer grp commons schemas params from (nullty)
570− -- ^ needs at least 1 argument
571− -> [Expression outer grp commons schemas params from (nullty)]
572− -- ^ or more
573− -> Expression outer grp commons schemas params from (nullty)
574−greatest x xs = UnsafeExpression $ "GREATEST("
575− <> commaSeparated (renderSQL <$> (x:xs)) <> ")"
576−
577−-- | >>> printSQL $ least currentTimestamp [null_]
578−-- LEAST(CURRENT_TIMESTAMP, NULL)
579−least
580− :: Expression outer grp commons schemas params from (nullty)
581− -- ^ needs at least 1 argument
582− -> [Expression outer grp commons schemas params from (nullty)]
583− -- ^ or more
584− -> Expression outer grp commons schemas params from (nullty)
585−least x xs = UnsafeExpression $ "LEAST("
586− <> commaSeparated (renderSQL <$> (x:xs)) <> ")"
587−
588315-- | >>> printSQL $ unsafeBinaryOp "OR" true false
589316-- (TRUE OR FALSE)
590−unsafeBinaryOp
591− :: ByteString
592− -- ^ operator
593− -> Expression outer grp commons schemas params from (ty0)
594− -> Expression outer grp commons schemas params from (ty1)
595− -> Expression outer grp commons schemas params from (ty2)
317+unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2
596318unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $
597319 renderSQL x <+> op <+> renderSQL y
598320
599−-- | >>> printSQL $ unsafeUnaryOp "NOT" true
321+binaryOp
322+ :: forall op sch schemas schema x y z.
323+ ( Has sch schemas schema
324+ , Has op schema ('Operator ('BinaryOp x y z)) )
325+ => OperatorDB schemas x y z
326+binaryOp = unsafeBinaryOp $ renderSymbol @op
327+
328+-- | >>> printSQL $ unsafeLeftOp "NOT" true
600329-- (NOT TRUE)
601−unsafeUnaryOp
602− :: ByteString
603− -- ^ operator
604− -> Expression outer grp commons schemas params from (ty0)
605− -> Expression outer grp commons schemas params from (ty1)
606−unsafeUnaryOp op x = UnsafeExpression $ parenthesized $
607− op <+> renderSQL x
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
608351
609352-- | >>> printSQL $ unsafeFunction "f" true
610353-- f(TRUE)
611−unsafeFunction
612− :: ByteString
613− -- ^ function
614− -> Expression outer grp commons schemas params from (xty)
615− -> Expression outer grp commons schemas params from (yty)
354+unsafeFunction :: ByteString -> x --> y
616355unsafeFunction fun x = UnsafeExpression $
617356 fun <> parenthesized (renderSQL x)
618357
619−-- | Helper for defining variadic functions.
620−unsafeVariadicFunction
621− :: SListI elems
622− => ByteString
623− -- ^ function
624− -> NP (Expression outer grp commons schemas params from) elems
625− -> Expression outer grp commons schemas params from ret
626−unsafeVariadicFunction fun x = UnsafeExpression $
627− fun <> parenthesized (commaSeparated (hcollapse (hmap (K . renderSQL) x)))
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
628377
629378instance ty `In` PGNum
630− => Num (Expression outer grp commons schemas params from (nullity ty)) where
379+ => Num (Expression outer commons grp schemas params from (null ty)) where
631380 (+) = unsafeBinaryOp "+"
632381 (-) = unsafeBinaryOp "-"
633382 (*) = unsafeBinaryOp "*"
@@ -639,7 +388,7 @@ instance ty `In` PGNum
639388 . show
640389
641390instance (ty `In` PGNum, ty `In` PGFloating) => Fractional
642− (Expression outer grp commons schemas params from (nullity ty)) where
391+ (Expression outer commons grp schemas params from (null ty)) where
643392 (/) = unsafeBinaryOp "/"
644393 fromRational
645394 = UnsafeExpression
@@ -649,7 +398,7 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Fractional
649398 . fromRat @Double
650399
651400instance (ty `In` PGNum, ty `In` PGFloating) => Floating
652− (Expression outer grp commons schemas params from (nullity ty)) where
401+ (Expression outer commons grp schemas params from (null ty)) where
653402 pi = UnsafeExpression "pi()"
654403 exp = unsafeFunction "exp"
655404 log = unsafeFunction "ln"
@@ -670,1757 +419,54 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating
670419 acosh x = log (x + sqrt (x*x - 1))
671420 atanh x = log ((1 + x) / (1 - x)) / 2
672421
673−-- | >>> :{
674−-- let
675−-- expression :: Expression outer grp commons schemas params from (nullity 'PGfloat4)
676−-- expression = atan2_ pi 2
677−-- in printSQL expression
678−-- :}
679−-- atan2(pi(), 2)
680−atan2_
681− :: float `In` PGFloating
682− => Expression outer grp commons schemas params from (nullity float)
683− -- ^ numerator
684− -> Expression outer grp commons schemas params from (nullity float)
685− -- ^ denominator
686− -> Expression outer grp commons schemas params from (nullity float)
687−atan2_ y x = UnsafeExpression $
688− "atan2(" <> renderSQL y <> ", " <> renderSQL x <> ")"
689−
690−-- When a `cast` is applied to an `Expression` of a known type, it
691−-- represents a run-time type conversion. The cast will succeed only if a
692−-- suitable type conversion operation has been defined.
693−--
694−-- | >>> printSQL $ true & cast int4
695−-- (TRUE :: int4)
696−cast
697− :: TypeExpression schemas ty1
698− -- ^ type to cast as
699− -> Expression outer grp commons schemas params from ty0
700− -- ^ value to convert
701− -> Expression outer grp commons schemas params from ty1
702−cast ty x = UnsafeExpression $ parenthesized $
703− renderSQL x <+> "::" <+> renderSQL ty
704−
705−-- | integer division, truncates the result
706−--
707−-- >>> :{
708−-- let
709−-- expression :: Expression outer grp commons schemas params from (nullity 'PGint2)
710−-- expression = 5 `quot_` 2
711−-- in printSQL expression
712−-- :}
713−-- (5 / 2)
714−quot_
715− :: int `In` PGIntegral
716− => Expression outer grp commons schemas params from (nullity int)
717− -- ^ numerator
718− -> Expression outer grp commons schemas params from (nullity int)
719− -- ^ denominator
720− -> Expression outer grp commons schemas params from (nullity int)
721−quot_ = unsafeBinaryOp "/"
722−
723−-- | remainder upon integer division
724−--
725−-- >>> :{
726−-- let
727−-- expression :: Expression outer grp commons schemas params from (nullity 'PGint2)
728−-- expression = 5 `rem_` 2
729−-- in printSQL expression
730−-- :}
731−-- (5 % 2)
732−rem_
733− :: int `In` PGIntegral
734− => Expression outer grp commons schemas params from (nullity int)
735− -- ^ numerator
736− -> Expression outer grp commons schemas params from (nullity int)
737− -- ^ denominator
738− -> Expression outer grp commons schemas params from (nullity int)
739−rem_ = unsafeBinaryOp "%"
740−
741−-- | >>> :{
742−-- let
743−-- expression :: Expression outer grp commons schemas params from (nullity 'PGfloat4)
744−-- expression = trunc pi
745−-- in printSQL expression
746−-- :}
747−-- trunc(pi())
748−trunc
749− :: frac `In` PGFloating
750− => Expression outer grp commons schemas params from (nullity frac)
751− -- ^ fractional number
752− -> Expression outer grp commons schemas params from (nullity frac)
753−trunc = unsafeFunction "trunc"
754−
755−-- | >>> :{
756−-- let
757−-- expression :: Expression outer grp commons schemas params from (nullity 'PGfloat4)
758−-- expression = round_ pi
759−-- in printSQL expression
760−-- :}
761−-- round(pi())
762−round_
763− :: frac `In` PGFloating
764− => Expression outer grp commons schemas params from (nullity frac)
765− -- ^ fractional number
766− -> Expression outer grp commons schemas params from (nullity frac)
767−round_ = unsafeFunction "round"
768−
769−-- | >>> :{
770−-- let
771−-- expression :: Expression outer grp commons schemas params from (nullity 'PGfloat4)
772−-- expression = ceiling_ pi
773−-- in printSQL expression
774−-- :}
775−-- ceiling(pi())
776−ceiling_
777− :: frac `In` PGFloating
778− => Expression outer grp commons schemas params from (nullity frac)
779− -- ^ fractional number
780− -> Expression outer grp commons schemas params from (nullity frac)
781−ceiling_ = unsafeFunction "ceiling"
782−
783−-- | A `Condition` is an `Expression`, which can evaluate
784−-- to `true`, `false` or `null_`. This is because SQL uses
785−-- a three valued logic.
786−type Condition outer grp commons schemas params from =
787− Expression outer grp commons schemas params from ('Null 'PGbool)
788−
789−-- | >>> printSQL true
790−-- TRUE
791−true :: Expression outer grp commons schemas params from (nullity 'PGbool)
792−true = UnsafeExpression "TRUE"
793−
794−-- | >>> printSQL false
795−-- FALSE
796−false :: Expression outer grp commons schemas params from (nullity 'PGbool)
797−false = UnsafeExpression "FALSE"
798−
799−-- | >>> printSQL $ not_ true
800−-- (NOT TRUE)
801−not_
802− :: Expression outer grp commons schemas params from (nullity 'PGbool)
803− -> Expression outer grp commons schemas params from (nullity 'PGbool)
804−not_ = unsafeUnaryOp "NOT"
805−
806−-- | >>> printSQL $ true .&& false
807−-- (TRUE AND FALSE)
808−(.&&)
809− :: Expression outer grp commons schemas params from (nullity 'PGbool)
810− -> Expression outer grp commons schemas params from (nullity 'PGbool)
811− -> Expression outer grp commons schemas params from (nullity 'PGbool)
812−infixr 3 .&&
813−(.&&) = unsafeBinaryOp "AND"
814−
815−-- | >>> printSQL $ true .|| false
816−-- (TRUE OR FALSE)
817−(.||)
818− :: Expression outer grp commons schemas params from (nullity 'PGbool)
819− -> Expression outer grp commons schemas params from (nullity 'PGbool)
820− -> Expression outer grp commons schemas params from (nullity 'PGbool)
821−infixr 2 .||
822−(.||) = unsafeBinaryOp "OR"
823−
824−-- | >>> :{
825−-- let
826−-- expression :: Expression outer grp commons schemas params from (nullity 'PGint2)
827−-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3
828−-- in printSQL expression
829−-- :}
830−-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END
831−caseWhenThenElse
832− :: [ ( Condition outer grp commons schemas params from
833− , Expression outer grp commons schemas params from ty
834− ) ]
835− -- ^ whens and thens
836− -> Expression outer grp commons schemas params from ty
837− -- ^ else
838− -> Expression outer grp commons schemas params from ty
839−caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat
840− [ "CASE"
841− , mconcat
842− [ mconcat
843− [ " WHEN ", renderSQL when_
844− , " THEN ", renderSQL then_
845− ]
846− | (when_,then_) <- whenThens
847− ]
848− , " ELSE ", renderSQL else_
849− , " END"
850− ]
851−
852−-- | >>> :{
853−-- let
854−-- expression :: Expression outer grp commons schemas params from (nullity 'PGint2)
855−-- expression = ifThenElse true 1 0
856−-- in printSQL expression
857−-- :}
858−-- CASE WHEN TRUE THEN 1 ELSE 0 END
859−ifThenElse
860− :: Condition outer grp commons schemas params from
861− -> Expression outer grp commons schemas params from ty -- ^ then
862− -> Expression outer grp commons schemas params from ty -- ^ else
863− -> Expression outer grp commons schemas params from ty
864−ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_
865−
866−-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`
867−-- will produce @NULL@s if one of their arguments is @NULL@.
868−--
869−-- >>> printSQL $ true .== null_
870−-- (TRUE = NULL)
871−(.==)
872− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
873− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
874− -> Condition outer grp commons schemas params from
875−(.==) = unsafeBinaryOp "="
876−infix 4 .==
877−
878−-- | >>> printSQL $ true ./= null_
879−-- (TRUE <> NULL)
880−(./=)
881− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
882− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
883− -> Condition outer grp commons schemas params from
884−(./=) = unsafeBinaryOp "<>"
885−infix 4 ./=
886−
887−-- | >>> printSQL $ true .>= null_
888−-- (TRUE >= NULL)
889−(.>=)
890− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
891− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
892− -> Condition outer grp commons schemas params from
893−(.>=) = unsafeBinaryOp ">="
894−infix 4 .>=
895−
896−-- | >>> printSQL $ true .< null_
897−-- (TRUE < NULL)
898−(.<)
899− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
900− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
901− -> Condition outer grp commons schemas params from
902−(.<) = unsafeBinaryOp "<"
903−infix 4 .<
904−
905−-- | >>> printSQL $ true .<= null_
906−-- (TRUE <= NULL)
907−(.<=)
908− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
909− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
910− -> Condition outer grp commons schemas params from
911−(.<=) = unsafeBinaryOp "<="
912−infix 4 .<=
913−
914−-- | >>> printSQL $ true .> null_
915−-- (TRUE > NULL)
916−(.>)
917− :: Expression outer grp commons schemas params from (nullity0 ty) -- ^ lhs
918− -> Expression outer grp commons schemas params from (nullity1 ty) -- ^ rhs
919− -> Condition outer grp commons schemas params from
920−(.>) = unsafeBinaryOp ">"
921−infix 4 .>
922−
923−-- | >>> printSQL currentDate
924−-- CURRENT_DATE
925−currentDate
926− :: Expression outer grp commons schemas params from (nullity 'PGdate)
927−currentDate = UnsafeExpression "CURRENT_DATE"
928−
929−-- | >>> printSQL currentTime
930−-- CURRENT_TIME
931−currentTime
932− :: Expression outer grp commons schemas params from (nullity 'PGtimetz)
933−currentTime = UnsafeExpression "CURRENT_TIME"
934−
935−-- | >>> printSQL currentTimestamp
936−-- CURRENT_TIMESTAMP
937−currentTimestamp
938− :: Expression outer grp commons schemas params from (nullity 'PGtimestamptz)
939−currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"
940−
941−-- | >>> printSQL localTime
942−-- LOCALTIME
943−localTime
944− :: Expression outer grp commons schemas params from (nullity 'PGtime)
945−localTime = UnsafeExpression "LOCALTIME"
946−
947−-- | >>> printSQL localTimestamp
948−-- LOCALTIMESTAMP
949−localTimestamp
950− :: Expression outer grp commons schemas params from (nullity 'PGtimestamp)
951−localTimestamp = UnsafeExpression "LOCALTIMESTAMP"
952−
953−{-----------------------------------------
954−text
955−-----------------------------------------}
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)
956438
957439instance IsString
958− (Expression outer grp commons schemas params from (nullity 'PGtext)) where
440+ (Expression outer commons grp schemas params from (null 'PGtext)) where
959441 fromString str = UnsafeExpression $
960442 "E\'" <> fromString (escape =<< str) <> "\'"
961− where
962− escape = \case
963− '\NUL' -> "\\0"
964− '\'' -> "''"
965− '"' -> "\\\""
966− '\b' -> "\\b"
967− '\n' -> "\\n"
968− '\r' -> "\\r"
969− '\t' -> "\\t"
970− '\\' -> "\\\\"
971− c -> [c]
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) <> "\'"
972451
973452instance Semigroup
974− (Expression outer grp commons schemas params from (nullity 'PGtext)) where
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
975463 (<>) = unsafeBinaryOp "||"
976464
977465instance Monoid
978− (Expression outer grp commons schemas params from (nullity 'PGtext)) where
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
979471 mempty = fromString ""
980472 mappend = (<>)
981−
982−-- | >>> printSQL $ lower "ARRRGGG"
983−-- lower(E'ARRRGGG')
984−lower
985− :: Expression outer grp commons schemas params from (nullity 'PGtext)
986− -- ^ string to lower case
987− -> Expression outer grp commons schemas params from (nullity 'PGtext)
988−lower = unsafeFunction "lower"
989−
990−-- | >>> printSQL $ upper "eeee"
991−-- upper(E'eeee')
992−upper
993− :: Expression outer grp commons schemas params from (nullity 'PGtext)
994− -- ^ string to upper case
995− -> Expression outer grp commons schemas params from (nullity 'PGtext)
996−upper = unsafeFunction "upper"
997−
998−-- | >>> printSQL $ charLength "four"
999−-- char_length(E'four')
1000−charLength
1001− :: Expression outer grp commons schemas params from (nullity 'PGtext)
1002− -- ^ string to measure
1003− -> Expression outer grp commons schemas params from (nullity 'PGint4)
1004−charLength = unsafeFunction "char_length"
1005−
1006−-- | The `like` expression returns true if the @string@ matches
1007−-- the supplied @pattern@. If @pattern@ does not contain percent signs
1008−-- or underscores, then the pattern only represents the string itself;
1009−-- in that case `like` acts like the equals operator. An underscore (_)
1010−-- in pattern stands for (matches) any single character; a percent sign (%)
1011−-- matches any sequence of zero or more characters.
1012−--
1013−-- >>> printSQL $ "abc" `like` "a%"
1014−-- (E'abc' LIKE E'a%')
1015−like
1016− :: Expression outer grp commons schemas params from (nullity 'PGtext)
1017− -- ^ string
1018− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1019− -- ^ pattern
1020− -> Expression outer grp commons schemas params from (nullity 'PGbool)
1021−like = unsafeBinaryOp "LIKE"
1022−
1023−-- | The key word ILIKE can be used instead of LIKE to make the
1024−-- match case-insensitive according to the active locale.
1025−--
1026−-- >>> printSQL $ "abc" `ilike` "a%"
1027−-- (E'abc' ILIKE E'a%')
1028−ilike
1029− :: Expression outer grp commons schemas params from (nullity 'PGtext)
1030− -- ^ string
1031− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1032− -- ^ pattern
1033− -> Expression outer grp commons schemas params from (nullity 'PGbool)
1034−ilike = unsafeBinaryOp "ILIKE"
1035−
1036−{-----------------------------------------
1037− -- json and jsonb support
1038−
1039−See https://www.postgresql.org/docs/10/static/functions-json.html -- most
1040−comments lifted directly from this page.
1041−
1042−Table 9.44: json and jsonb operators
1043−-----------------------------------------}
1044−
1045−-- | Get JSON value (object field or array element) at a key.
1046−(.->)
1047− :: (json `In` PGJsonType, key `In` PGJsonKey)
1048− => Expression outer grp commons schemas params from (nullity json)
1049− -> Expression outer grp commons schemas params from (nullity key)
1050− -> Expression outer grp commons schemas params from ('Null json)
1051−infixl 8 .->
1052−(.->) = unsafeBinaryOp "->"
1053−
1054−-- | Get JSON value (object field or array element) at a key, as text.
1055−(.->>)
1056− :: (json `In` PGJsonType, key `In` PGJsonKey)
1057− => Expression outer grp commons schemas params from (nullity json)
1058− -> Expression outer grp commons schemas params from (nullity key)
1059− -> Expression outer grp commons schemas params from ('Null 'PGtext)
1060−infixl 8 .->>
1061−(.->>) = unsafeBinaryOp "->>"
1062−
1063−-- | Get JSON value at a specified path.
1064−(.#>)
1065− :: (json `In` PGJsonType, PGTextArray "(.#>)" path)
1066− => Expression outer grp commons schemas params from (nullity json)
1067− -> Expression outer grp commons schemas params from (nullity path)
1068− -> Expression outer grp commons schemas params from ('Null json)
1069−infixl 8 .#>
1070−(.#>) = unsafeBinaryOp "#>"
1071−
1072−-- | Get JSON value at a specified path as text.
1073−(.#>>)
1074− :: (json `In` PGJsonType, PGTextArray "(.#>>)" path)
1075− => Expression outer grp commons schemas params from (nullity json)
1076− -> Expression outer grp commons schemas params from (nullity path)
1077− -> Expression outer grp commons schemas params from ('Null 'PGtext)
1078−infixl 8 .#>>
1079−(.#>>) = unsafeBinaryOp "#>>"
1080−
1081−-- Additional jsonb operators
1082−
1083−-- | Does the left JSON value contain the right JSON path/value entries at the
1084−-- top level?
1085−(.@>)
1086− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1087− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1088− -> Condition outer grp commons schemas params from
1089−infixl 9 .@>
1090−(.@>) = unsafeBinaryOp "@>"
1091−
1092−-- | Are the left JSON path/value entries contained at the top level within the
1093−-- right JSON value?
1094−(.<@)
1095− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1096− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1097− -> Condition outer grp commons schemas params from
1098−infixl 9 .<@
1099−(.<@) = unsafeBinaryOp "<@"
1100−
1101−-- | Does the string exist as a top-level key within the JSON value?
1102−(.?)
1103− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1104− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1105− -> Condition outer grp commons schemas params from
1106−infixl 9 .?
1107−(.?) = unsafeBinaryOp "?"
1108−
1109−-- | Do any of these array strings exist as top-level keys?
1110−(.?|)
1111− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1112− -> Expression outer grp commons schemas params from (nullity ('PGvararray ('NotNull 'PGtext)))
1113− -> Condition outer grp commons schemas params from
1114−infixl 9 .?|
1115−(.?|) = unsafeBinaryOp "?|"
1116−
1117−-- | Do all of these array strings exist as top-level keys?
1118−(.?&)
1119− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1120− -> Expression outer grp commons schemas params from (nullity ('PGvararray ('NotNull 'PGtext)))
1121− -> Condition outer grp commons schemas params from
1122−infixl 9 .?&
1123−(.?&) = unsafeBinaryOp "?&"
1124−
1125−-- | Concatenate two jsonb values into a new jsonb value.
1126−instance Semigroup
1127− (Expression outer grp commons schemas params from (nullity 'PGjsonb)) where
1128− (<>) = unsafeBinaryOp "||"
1129−
1130−-- | Delete a key or keys from a JSON object, or remove an array element.
1131−--
1132−-- If the right operand is..
1133−--
1134−-- @ text @: Delete key/value pair or string element from left operand. Key/value pairs
1135−-- are matched based on their key value.
1136−--
1137−-- @ text[] @: Delete multiple key/value pairs or string elements
1138−-- from left operand. Key/value pairs are matched based on their key value.
1139−--
1140−-- @ integer @: Delete the array element with specified index (Negative integers
1141−-- count from the end). Throws an error if top level container is not an array.
1142−(.-.)
1143− :: (key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]) -- hlint error without parens here
1144− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1145− -> Expression outer grp commons schemas params from (nullity key)
1146− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1147−infixl 6 .-.
1148−(.-.) = unsafeBinaryOp "-"
1149−
1150−-- | Delete the field or element with specified path (for JSON arrays, negative
1151−-- integers count from the end)
1152−(#-.)
1153− :: PGTextArray "(#-.)" arrayty
1154− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1155− -> Expression outer grp commons schemas params from (nullity arrayty)
1156− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1157−infixl 6 #-.
1158−(#-.) = unsafeBinaryOp "#-"
1159−
1160−{-----------------------------------------
1161−Table 9.45: JSON creation functions
1162−-----------------------------------------}
1163−
1164−-- | Literal binary JSON
1165−jsonbLit
1166− :: JSON.ToJSON x
1167− => x -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1168−jsonbLit = cast jsonb . UnsafeExpression
1169− . singleQuotedUtf8 . toStrict . JSON.encode
1170−
1171−-- | Literal JSON
1172−jsonLit
1173− :: JSON.ToJSON x
1174− => x -> Expression outer grp commons schemas params from (nullity 'PGjson)
1175−jsonLit = cast json . UnsafeExpression
1176− . singleQuotedUtf8 . toStrict . JSON.encode
1177−
1178−-- | Returns the value as json. Arrays and composites are converted
1179−-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1180−-- type to json, the cast function will be used to perform the conversion;
1181−-- otherwise, a scalar value is produced. For any scalar type other than a
1182−-- number, a Boolean, or a null value, the text representation will be used, in
1183−-- such a fashion that it is a valid json value.
1184−toJson
1185− :: Expression outer grp commons schemas params from (nullity ty)
1186− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1187−toJson = unsafeFunction "to_json"
1188−
1189−-- | Returns the value as jsonb. Arrays and composites are converted
1190−-- (recursively) to arrays and objects; otherwise, if there is a cast from the
1191−-- type to json, the cast function will be used to perform the conversion;
1192−-- otherwise, a scalar value is produced. For any scalar type other than a
1193−-- number, a Boolean, or a null value, the text representation will be used, in
1194−-- such a fashion that it is a valid jsonb value.
1195−toJsonb
1196− :: Expression outer grp commons schemas params from (nullity ty)
1197− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1198−toJsonb = unsafeFunction "to_jsonb"
1199−
1200−-- | Returns the array as a JSON array. A PostgreSQL multidimensional array
1201−-- becomes a JSON array of arrays.
1202−arrayToJson
1203− :: PGArray "arrayToJson" arr
1204− => Expression outer grp commons schemas params from (nullity arr)
1205− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1206−arrayToJson = unsafeFunction "array_to_json"
1207−
1208−-- | Returns the row as a JSON object.
1209−rowToJson
1210− :: Expression outer grp commons schemas params from (nullity ('PGcomposite ty))
1211− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1212−rowToJson = unsafeFunction "row_to_json"
1213−
1214−-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic
1215−-- argument list.
1216−jsonBuildArray
1217− :: SListI elems
1218− => NP (Expression outer grp commons schemas params from) elems
1219− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1220−jsonBuildArray = unsafeVariadicFunction "json_build_array"
1221−
1222−-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a
1223−-- variadic argument list.
1224−jsonbBuildArray
1225− :: SListI elems
1226− => NP (Expression outer grp commons schemas params from) elems
1227− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1228−jsonbBuildArray = unsafeVariadicFunction "jsonb_build_array"
1229−
1230−unsafeRowFunction
1231− :: SOP.SListI elems
1232− => NP (Aliased (Expression outer grp commons schemas params from)) elems
1233− -> [ByteString]
1234−unsafeRowFunction =
1235− (`appEndo` []) . hcfoldMap (Proxy :: SOP.Proxy SOP.Top)
1236− (\(col `As` name) -> Endo $ \xs ->
1237− renderAliasString name : renderSQL col : xs)
1238− where
1239− renderAliasString :: KnownSymbol alias => Alias alias -> ByteString
1240− renderAliasString = singleQuotedText . fromString . symbolVal
1241−
1242−-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic
1243−-- argument list. The elements of the argument list must alternate between text
1244−-- and values.
1245−jsonBuildObject
1246− :: SOP.SListI elems
1247− => NP (Aliased (Expression outer grp commons schemas params from)) elems
1248− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1249−jsonBuildObject
1250− = unsafeFunction "json_build_object"
1251− . UnsafeExpression
1252− . commaSeparated
1253− . unsafeRowFunction
1254−
1255−-- | Builds a possibly-heterogeneously-typed (binary) JSON object out of a
1256−-- variadic argument list. The elements of the argument list must alternate
1257−-- between text and values.
1258−jsonbBuildObject
1259− :: SOP.SListI elems
1260− => NP (Aliased (Expression outer grp commons schemas params from)) elems
1261− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1262−jsonbBuildObject
1263− = unsafeFunction "jsonb_build_object"
1264− . UnsafeExpression
1265− . commaSeparated
1266− . unsafeRowFunction
1267−
1268−-- | Builds a JSON object out of a text array. The array must have either
1269−-- exactly one dimension with an even number of members, in which case they are
1270−-- taken as alternating key/value pairs, or two dimensions such that each inner
1271−-- array has exactly two elements, which are taken as a key/value pair.
1272−jsonObject
1273− :: PGArrayOf "jsonObject" arr ('NotNull 'PGtext)
1274− => Expression outer grp commons schemas params from (nullity arr)
1275− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1276−jsonObject = unsafeFunction "json_object"
1277−
1278−-- | Builds a binary JSON object out of a text array. The array must have either
1279−-- exactly one dimension with an even number of members, in which case they are
1280−-- taken as alternating key/value pairs, or two dimensions such that each inner
1281−-- array has exactly two elements, which are taken as a key/value pair.
1282−jsonbObject
1283− :: PGArrayOf "jsonbObject" arr ('NotNull 'PGtext)
1284− => Expression outer grp commons schemas params from (nullity arr)
1285− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1286−jsonbObject = unsafeFunction "jsonb_object"
1287−
1288−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1289−-- keys and one for values, that are zipped pairwise to create a JSON object.
1290−jsonZipObject
1291− :: ( PGArrayOf "jsonZipObject" keysArray ('NotNull 'PGtext)
1292− , PGArrayOf "jsonZipObject" valuesArray ('NotNull 'PGtext))
1293− => Expression outer grp commons schemas params from (nullity keysArray)
1294− -> Expression outer grp commons schemas params from (nullity valuesArray)
1295− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1296−jsonZipObject ks vs =
1297− unsafeVariadicFunction "json_object" (ks :* vs :* Nil)
1298−
1299−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for
1300−-- keys and one for values, that are zipped pairwise to create a binary JSON
1301−-- object.
1302−jsonbZipObject
1303− :: ( PGArrayOf "jsonbZipObject" keysArray ('NotNull 'PGtext)
1304− , PGArrayOf "jsonbZipObject" valuesArray ('NotNull 'PGtext))
1305− => Expression outer grp commons schemas params from (nullity keysArray)
1306− -> Expression outer grp commons schemas params from (nullity valuesArray)
1307− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1308−jsonbZipObject ks vs =
1309− unsafeVariadicFunction "jsonb_object" (ks :* vs :* Nil)
1310−
1311−{-----------------------------------------
1312−Table 9.46: JSON processing functions
1313−-----------------------------------------}
1314−
1315−-- | Returns the number of elements in the outermost JSON array.
1316−jsonArrayLength
1317− :: Expression outer grp commons schemas params from (nullity 'PGjson)
1318− -> Expression outer grp commons schemas params from (nullity 'PGint4)
1319−jsonArrayLength = unsafeFunction "json_array_length"
1320−
1321−-- | Returns the number of elements in the outermost binary JSON array.
1322−jsonbArrayLength
1323− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1324− -> Expression outer grp commons schemas params from (nullity 'PGint4)
1325−jsonbArrayLength = unsafeFunction "jsonb_array_length"
1326−
1327−-- | Returns JSON value pointed to by the given path (equivalent to #>
1328−-- operator).
1329−jsonExtractPath
1330− :: SListI elems
1331− => Expression outer grp commons schemas params from (nullity 'PGjson)
1332− -> NP (Expression outer grp commons schemas params from) elems
1333− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1334−jsonExtractPath x xs =
1335− unsafeVariadicFunction "json_extract_path" (x :* xs)
1336−
1337−-- | Returns JSON value pointed to by the given path (equivalent to #>
1338−-- operator).
1339−jsonbExtractPath
1340− :: SListI elems
1341− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1342− -> NP (Expression outer grp commons schemas params from) elems
1343− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1344−jsonbExtractPath x xs =
1345− unsafeVariadicFunction "jsonb_extract_path" (x :* xs)
1346−
1347−-- | Returns JSON value pointed to by the given path (equivalent to #>
1348−-- operator), as text.
1349−jsonExtractPathAsText
1350− :: SListI elems
1351− => Expression outer grp commons schemas params from (nullity 'PGjson)
1352− -> NP (Expression outer grp commons schemas params from) elems
1353− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1354−jsonExtractPathAsText x xs =
1355− unsafeVariadicFunction "json_extract_path_text" (x :* xs)
1356−
1357−-- | Returns JSON value pointed to by the given path (equivalent to #>
1358−-- operator), as text.
1359−jsonbExtractPathAsText
1360− :: SListI elems
1361− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1362− -> NP (Expression outer grp commons schemas params from) elems
1363− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1364−jsonbExtractPathAsText x xs =
1365− unsafeVariadicFunction "jsonb_extract_path_text" (x :* xs)
1366−
1367−-- | Returns the type of the outermost JSON value as a text string. Possible
1368−-- types are object, array, string, number, boolean, and null.
1369−jsonTypeof
1370− :: Expression outer grp commons schemas params from (nullity 'PGjson)
1371− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1372−jsonTypeof = unsafeFunction "json_typeof"
1373−
1374−-- | Returns the type of the outermost binary JSON value as a text string.
1375−-- Possible types are object, array, string, number, boolean, and null.
1376−jsonbTypeof
1377− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1378− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1379−jsonbTypeof = unsafeFunction "jsonb_typeof"
1380−
1381−-- | Returns its argument with all object fields that have null values omitted.
1382−-- Other null values are untouched.
1383−jsonStripNulls
1384− :: Expression outer grp commons schemas params from (nullity 'PGjson)
1385− -> Expression outer grp commons schemas params from (nullity 'PGjson)
1386−jsonStripNulls = unsafeFunction "json_strip_nulls"
1387−
1388−-- | Returns its argument with all object fields that have null values omitted.
1389−-- Other null values are untouched.
1390−jsonbStripNulls
1391− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1392− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1393−jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"
1394−
1395−-- | @ jsonbSet target path new_value create_missing @
1396−--
1397−-- Returns target with the section designated by path replaced by new_value,
1398−-- or with new_value added if create_missing is true ( default is true) and the
1399−-- item designated by path does not exist. As with the path orientated
1400−-- operators, negative integers that appear in path count from the end of JSON
1401−-- arrays.
1402−jsonbSet
1403− :: PGTextArray "jsonbSet" arr
1404− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1405− -> Expression outer grp commons schemas params from (nullity arr)
1406− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1407− -> Maybe (Expression outer grp commons schemas params from (nullity 'PGbool))
1408− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1409−jsonbSet tgt path val createMissing = case createMissing of
1410− Just m -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* m :* Nil)
1411− Nothing -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* Nil)
1412−
1413−-- | @ jsonbInsert target path new_value insert_after @
1414−--
1415−-- Returns target with new_value inserted. If target section designated by
1416−-- path is in a JSONB array, new_value will be inserted before target or after
1417−-- if insert_after is true (default is false). If target section designated by
1418−-- path is in JSONB object, new_value will be inserted only if target does not
1419−-- exist. As with the path orientated operators, negative integers that appear
1420−-- in path count from the end of JSON arrays.
1421−jsonbInsert
1422− :: PGTextArray "jsonbInsert" arr
1423− => Expression outer grp commons schemas params from (nullity 'PGjsonb)
1424− -> Expression outer grp commons schemas params from (nullity arr)
1425− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1426− -> Maybe (Expression outer grp commons schemas params from (nullity 'PGbool))
1427− -> Expression outer grp commons schemas params from (nullity 'PGjsonb)
1428−jsonbInsert tgt path val insertAfter = case insertAfter of
1429− Just i -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* i :* Nil)
1430− Nothing -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* Nil)
1431−
1432−-- | Returns its argument as indented JSON text.
1433−jsonbPretty
1434− :: Expression outer grp commons schemas params from (nullity 'PGjsonb)
1435− -> Expression outer grp commons schemas params from (nullity 'PGtext)
1436−jsonbPretty = unsafeFunction "jsonb_pretty"
1437−
1438−{-----------------------------------------
1439−aggregation
1440−-----------------------------------------}
1441−
1442−{- |
1443−`Aggregate` functions compute a single result from a set of input values.
1444−`Aggregate` functions can be used as `GroupedBy` `Expression`s as well
1445−as `WindowFunction`s.
1446−-}
1447−class Aggregate expr1 expr2 aggr
1448− | aggr -> expr1, aggr -> expr2 where
1449−
1450− -- | A special aggregation that does not require an input
1451− --
1452− -- >>> :{
1453− -- let
1454− -- expression :: Expression '[] ('Grouped bys) commons schemas params from ('NotNull 'PGint8)
1455− -- expression = countStar
1456− -- in printSQL expression
1457− -- :}
1458− -- count(*)
1459− countStar :: aggr ('NotNull 'PGint8)
1460−
1461− -- | >>> :{
1462− -- let
1463− -- expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity ty]] ('NotNull 'PGint8)
1464− -- expression = count (All #col)
1465− -- in printSQL expression
1466− -- :}
1467− -- count(ALL "col")
1468− count
1469− :: expr1 ty
1470− -- ^ what to count
1471− -> aggr ('NotNull 'PGint8)
1472−
1473− -- | >>> :{
1474− -- let
1475− -- expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('NotNull 'PGnumeric)
1476− -- expression = sum_ (Distinct #col)
1477− -- in printSQL expression
1478− -- :}
1479− -- sum(DISTINCT "col")
1480− sum_
1481− :: ty `In` PGNum
1482− => expr1 (nullity ty)
1483− -> aggr ('NotNull ty)
1484−
1485− -- | input values, including nulls, concatenated into an array
1486− arrayAgg
1487− :: expr1 ty
1488− -> aggr ('Null ('PGvararray ty))
1489−
1490− -- | aggregates values as a JSON array
1491− jsonAgg
1492− :: expr1 ty
1493− -> aggr ('Null 'PGjson)
1494−
1495− -- | aggregates values as a JSON array
1496− jsonbAgg
1497− :: expr1 ty
1498− -> aggr ('Null 'PGjsonb)
1499−
1500− {- |
1501− the bitwise AND of all non-null input values, or null if none
1502− >>> :{
1503− let
1504− expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity 'PGint4]] ('Null 'PGint4)
1505− expression = bitAnd (Distinct #col)
1506− in printSQL expression
1507− :}
1508− bit_and(DISTINCT "col")
1509− -}
1510− bitAnd
1511− :: int `In` PGIntegral
1512− => expr1 (nullity int)
1513− -- ^ what to aggregate
1514− -> aggr ('Null int)
1515−
1516− {- |
1517− the bitwise OR of all non-null input values, or null if none
1518−
1519− >>> :{
1520− let
1521− expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity 'PGint4]] ('Null 'PGint4)
1522− expression = bitOr (All #col)
1523− in printSQL expression
1524− :}
1525− bit_or(ALL "col")
1526− -}
1527− bitOr
1528− :: int `In` PGIntegral
1529− => expr1 (nullity int)
1530− -- ^ what to aggregate
1531− -> aggr ('Null int)
1532−
1533− {- |
1534− true if all input values are true, otherwise false
1535−
1536− >>> :{
1537− let
1538− winFun :: WindowFunction '[] 'Ungrouped commons schemas params '[tab ::: '["col" ::: nullity 'PGbool]] ('Null 'PGbool)
1539− winFun = boolAnd #col
1540− in printSQL winFun
1541− :}
1542− bool_and("col")
1543− -}
1544− boolAnd
1545− :: expr1 (nullity 'PGbool)
1546− -- ^ what to aggregate
1547− -> aggr ('Null 'PGbool)
1548−
1549− {- |
1550− true if at least one input value is true, otherwise false
1551−
1552− >>> :{
1553− let
1554− expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity 'PGbool]] ('Null 'PGbool)
1555− expression = boolOr (All #col)
1556− in printSQL expression
1557− :}
1558− bool_or(ALL "col")
1559− -}
1560− boolOr
1561− :: expr1(nullity 'PGbool)
1562− -- ^ what to aggregate
1563− -> aggr ('Null 'PGbool)
1564−
1565− {- |
1566− equivalent to `boolAnd`
1567−
1568− >>> :{
1569− let
1570− expression :: Expression '[] ('Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity 'PGbool]] ('Null 'PGbool)
1571− expression = every (Distinct #col)
1572− in printSQL expression
1573− :}
1574− every(DISTINCT "col")
1575− -}
1576− every
1577− :: expr1 (nullity 'PGbool)
1578− -- ^ what to aggregate
1579− -> aggr ('Null 'PGbool)
1580−
1581− {- |maximum value of expression across all input values-}
1582− max_
1583− :: expr1 (nullity ty)
1584− -- ^ what to maximize
1585− -> aggr ('Null ty)
1586−
1587− -- | minimum value of expression across all input values
1588− min_
1589− :: expr1 (nullity ty)
1590− -- ^ what to minimize
1591− -> aggr ('Null ty)
1592−
1593− -- | the average (arithmetic mean) of all input values
1594− avg
1595− :: expr1 (nullity ty)
1596− -- ^ what to average
1597− -> aggr ('Null (PGAvg ty))
1598−
1599− {- | correlation coefficient
1600− >>> :{
1601− let
1602− expression :: Expression '[] ('Grouped g) c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1603− expression = corr (All (#y :*: #x))
1604− in printSQL expression
1605− :}
1606− corr(ALL "y", "x")
1607− -}
1608− corr
1609− :: expr2 (nullity 'PGfloat8)
1610− -> aggr ('Null 'PGfloat8)
1611−
1612− {- | population covariance
1613− >>> :{
1614− let
1615− expression :: Expression '[] ('Grouped g) c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1616− expression = covarPop (All (#y :*: #x))
1617− in printSQL expression
1618− :}
1619− covar_pop(ALL "y", "x")
1620− -}
1621− covarPop
1622− :: expr2 (nullity 'PGfloat8)
1623− -> aggr ('Null 'PGfloat8)
1624−
1625− {- | sample covariance
1626− >>> :{
1627− let
1628− winFun :: WindowFunction '[] 'Ungrouped c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1629− winFun = covarSamp (#y :*: #x)
1630− in printSQL winFun
1631− :}
1632− covar_samp("y", "x")
1633− -}
1634− covarSamp
1635− :: expr2 (nullity 'PGfloat8)
1636− -> aggr ('Null 'PGfloat8)
1637−
1638− {- | average of the independent variable (sum(X)/N)
1639− >>> :{
1640− let
1641− expression :: Expression '[] ('Grouped g) c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1642− expression = regrAvgX (All (#y :*: #x))
1643− in printSQL expression
1644− :}
1645− regr_avgx(ALL "y", "x")
1646− -}
1647− regrAvgX
1648− :: expr2 (nullity 'PGfloat8)
1649− -> aggr ('Null 'PGfloat8)
1650−
1651− {- | average of the dependent variable (sum(Y)/N)
1652− >>> :{
1653− let
1654− winFun :: WindowFunction '[] 'Ungrouped c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1655− winFun = regrAvgY (#y :*: #x)
1656− in printSQL winFun
1657− :}
1658− regr_avgy("y", "x")
1659− -}
1660− regrAvgY
1661− :: expr2 (nullity 'PGfloat8)
1662− -> aggr ('Null 'PGfloat8)
1663−
1664− {- | number of input rows in which both expressions are nonnull
1665− >>> :{
1666− let
1667− winFun :: WindowFunction '[] 'Ungrouped c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGint8)
1668− winFun = regrCount (#y :*: #x)
1669− in printSQL winFun
1670− :}
1671− regr_count("y", "x")
1672− -}
1673− regrCount
1674− :: expr2 (nullity 'PGfloat8)
1675− -> aggr ('Null 'PGint8)
1676−
1677− {- | y-intercept of the least-squares-fit linear equation determined by the (X, Y) pairs
1678− >>> :{
1679− let
1680− expression :: Expression '[] ('Grouped g) c s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)
1681− expression = regrIntercept (All (#y :*: #x))
1682− in printSQL expression
1683− :}
1684− regr_intercept(ALL "y", "x")
1685− -}
1686− regrIntercept
1687− :: expr2 (nullity 'PGfloat8)
1688− -> aggr ('Null 'PGfloat8)
1689−
1690− -- | @regr_r2(Y, X)@, square of the correlation coefficient
1691− regrR2
1692− :: expr2 (nullity 'PGfloat8)
1693− -> aggr ('Null 'PGfloat8)
1694−
1695− -- | @regr_slope(Y, X)@, slope of the least-squares-fit linear equation
1696− -- determined by the (X, Y) pairs
1697− regrSlope
1698− :: expr2 (nullity 'PGfloat8)
1699− -> aggr ('Null 'PGfloat8)
1700−
1701− -- | @regr_sxx(Y, X)@, sum(X^2) - sum(X)^2/N
1702− -- (“sum of squares” of the independent variable)
1703− regrSxx
1704− :: expr2 (nullity 'PGfloat8)
1705− -> aggr ('Null 'PGfloat8)
1706−
1707− -- | @regr_sxy(Y, X)@, sum(X*Y) - sum(X) * sum(Y)/N
1708− -- (“sum of products” of independent times dependent variable)
1709− regrSxy
1710− :: expr2 (nullity 'PGfloat8)
1711− -> aggr ('Null 'PGfloat8)
1712−
1713− -- | @regr_syy(Y, X)@, sum(Y^2) - sum(Y)^2/N
1714− -- (“sum of squares” of the dependent variable)
1715− regrSyy
1716− :: expr2 (nullity 'PGfloat8)
1717− -> aggr ('Null 'PGfloat8)
1718−
1719− -- | historical alias for `stddevSamp`
1720− stddev
1721− :: expr1 (nullity ty)
1722− -> aggr ('Null (PGAvg ty))
1723−
1724− -- | population standard deviation of the input values
1725− stddevPop
1726− :: expr1 (nullity ty)
1727− -> aggr ('Null (PGAvg ty))
1728−
1729− -- | sample standard deviation of the input values
1730− stddevSamp
1731− :: expr1 (nullity ty)
1732− -> aggr ('Null (PGAvg ty))
1733−
1734− -- | historical alias for `varSamp`
1735− variance
1736− :: expr1 (nullity ty)
1737− -> aggr ('Null (PGAvg ty))
1738−
1739− -- | population variance of the input values
1740− -- (square of the population standard deviation)
1741− varPop
1742− :: expr1 (nullity ty)
1743− -> aggr ('Null (PGAvg ty))
1744−
1745− -- | sample variance of the input values
1746− -- (square of the sample standard deviation)
1747− varSamp
1748− :: expr1 (nullity ty)
1749− -> aggr ('Null (PGAvg ty))
1750−
1751−{- |
1752−`Distinction`s are used for the input of `Aggregate` `Expression`s.
1753−`All` invokes the aggregate once for each input row.
1754−`Distinct` invokes the aggregate once for each distinct value of the expression
1755−(or distinct set of values, for multiple expressions) found in the input
1756−-}
1757−data Distinction expr ty
1758− = All (expr ty)
1759− | Distinct (expr ty)
1760− deriving (GHC.Generic,Show,Eq,Ord)
1761−instance NFData (Distinction (Expression outer grp commons schemas params from) ty)
1762−instance RenderSQL (Distinction (Expression outer grp commons schemas params from) ty) where
1763− renderSQL = \case
1764− All x -> "ALL" <+> renderSQL x
1765− Distinct x -> "DISTINCT" <+> renderSQL x
1766−instance RenderSQL
1767− (Distinction
1768− ( Expression outer grp commons schemas params from
1769− :*:
1770− Expression outer grp commons schemas params from) xty ) where
1771− renderSQL = \case
1772− All (x :*: x') ->
1773− "ALL" <+> renderSQL x <> ", " <> renderSQL x'
1774− Distinct (x :*: x') ->
1775− "DISTINCT" <+> renderSQL x <> ", " <> renderSQL x'
1776−
1777−instance Aggregate
1778− (Distinction (Expression outer 'Ungrouped commons schemas params from))
1779− (Distinction (Expression outer 'Ungrouped commons schemas params from :*: Expression outer 'Ungrouped commons schemas params from))
1780− (Expression outer ('Grouped bys) commons schemas params from) where
1781− countStar = UnsafeExpression "count(*)"
1782− count = unsafeAggregate1 "count"
1783− sum_ = unsafeAggregate1 "sum"
1784− arrayAgg = unsafeAggregate1 "array_agg"
1785− jsonAgg = unsafeAggregate1 "json_agg"
1786− jsonbAgg = unsafeAggregate1 "jsonb_agg"
1787− bitAnd = unsafeAggregate1 "bit_and"
1788− bitOr = unsafeAggregate1 "bit_or"
1789− boolAnd = unsafeAggregate1 "bool_and"
1790− boolOr = unsafeAggregate1 "bool_or"
1791− every = unsafeAggregate1 "every"
1792− max_ = unsafeAggregate1 "max"
1793− min_ = unsafeAggregate1 "min"
1794− avg = unsafeAggregate1 "avg"
1795− corr = unsafeAggregate2 "corr"
1796− covarPop = unsafeAggregate2 "covar_pop"
1797− covarSamp = unsafeAggregate2 "covar_samp"
1798− regrAvgX = unsafeAggregate2 "regr_avgx"
1799− regrAvgY = unsafeAggregate2 "regr_avgy"
1800− regrCount = unsafeAggregate2 "regr_count"
1801− regrIntercept = unsafeAggregate2 "regr_intercept"
1802− regrR2 = unsafeAggregate2 "regr_r2"
1803− regrSlope = unsafeAggregate2 "regr_slope"
1804− regrSxx = unsafeAggregate2 "regr_sxx"
1805− regrSxy = unsafeAggregate2 "regr_sxy"
1806− regrSyy = unsafeAggregate2 "regr_syy"
1807− stddev = unsafeAggregate1 "stddev"
1808− stddevPop = unsafeAggregate1 "stddev_pop"
1809− stddevSamp = unsafeAggregate1 "stddev_samp"
1810− variance = unsafeAggregate1 "variance"
1811− varPop = unsafeAggregate1 "var_pop"
1812− varSamp = unsafeAggregate1 "var_samp"
1813−instance Aggregate
1814− (Expression outer grp commons schemas params from)
1815− (Expression outer grp commons schemas params from :*: Expression outer grp commons schemas params from)
1816− (WindowFunction outer grp commons schemas params from) where
1817− countStar = UnsafeWindowFunction "count(*)"
1818− count = unsafeWindowFunction1 "count"
1819− sum_ = unsafeWindowFunction1 "sum"
1820− arrayAgg = unsafeWindowFunction1 "array_agg"
1821− jsonAgg = unsafeWindowFunction1 "json_agg"
1822− jsonbAgg = unsafeWindowFunction1 "jsonb_agg"
1823− bitAnd = unsafeWindowFunction1 "bit_and"
1824− bitOr = unsafeWindowFunction1 "bit_or"
1825− boolAnd = unsafeWindowFunction1 "bool_and"
1826− boolOr = unsafeWindowFunction1 "bool_or"
1827− every = unsafeWindowFunction1 "every"
1828− max_ = unsafeWindowFunction1 "max"
1829− min_ = unsafeWindowFunction1 "min"
1830− avg = unsafeWindowFunction1 "avg"
1831− corr = unsafeWindowFunction2 "corr"
1832− covarPop = unsafeWindowFunction2 "covar_pop"
1833− covarSamp = unsafeWindowFunction2 "covar_samp"
1834− regrAvgX = unsafeWindowFunction2 "regr_avgx"
1835− regrAvgY = unsafeWindowFunction2 "regr_avgy"
1836− regrCount = unsafeWindowFunction2 "regr_count"
1837− regrIntercept = unsafeWindowFunction2 "regr_intercept"
1838− regrR2 = unsafeWindowFunction2 "regr_r2"
1839− regrSlope = unsafeWindowFunction2 "regr_slope"
1840− regrSxx = unsafeWindowFunction2 "regr_sxx"
1841− regrSxy = unsafeWindowFunction2 "regr_sxy"
1842− regrSyy = unsafeWindowFunction2 "regr_syy"
1843− stddev = unsafeWindowFunction1 "stddev"
1844− stddevPop = unsafeWindowFunction1 "stddev_pop"
1845− stddevSamp = unsafeWindowFunction1 "stddev_samp"
1846− variance = unsafeWindowFunction1 "variance"
1847− varPop = unsafeWindowFunction1 "var_pop"
1848− varSamp = unsafeWindowFunction1 "var_samp"
1849−
1850−-- | escape hatch to define aggregate functions
1851−unsafeAggregate1
1852− :: ByteString -- ^ aggregate function
1853− -> Distinction (Expression outer 'Ungrouped commons schemas params from) xty
1854− -> Expression outer ('Grouped bys) commons schemas params from yty
1855−unsafeAggregate1 fun x = UnsafeExpression $ mconcat
1856− [fun, "(", renderSQL x, ")"]
1857−
1858−-- | escape hatch to define aggregate binary functions
1859−unsafeAggregate2
1860− :: ByteString -- ^ aggregate function
1861− -> Distinction (Expression outer 'Ungrouped commons schemas params from :*: Expression outer 'Ungrouped commons schemas params from) xty
1862− -> Expression outer ('Grouped bys) commons schemas params from yty
1863−unsafeAggregate2 fun xx = UnsafeExpression $ mconcat
1864− [fun, "(", renderSQL xx, ")"]
1865−
1866−-- | A type family that calculates `PGAvg` type of a `PGType`.
1867−type family PGAvg ty where
1868− PGAvg 'PGint2 = 'PGnumeric
1869− PGAvg 'PGint4 = 'PGnumeric
1870− PGAvg 'PGint8 = 'PGnumeric
1871− PGAvg 'PGnumeric = 'PGnumeric
1872− PGAvg 'PGfloat4 = 'PGfloat8
1873− PGAvg 'PGfloat8 = 'PGfloat8
1874− PGAvg 'PGinterval = 'PGinterval
1875− PGAvg pg = TypeError
1876− ('Text "Squeal type error: No average for " ':<>: 'ShowType pg)
1877−
1878−{-----------------------------------------
1879−type expressions
1880−-----------------------------------------}
1881−
1882−-- | `TypeExpression`s are used in `cast`s and
1883−-- `Squeal.PostgreSQL.Definition.createTable` commands.
1884−newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)
1885− = UnsafeTypeExpression { renderTypeExpression :: ByteString }
1886− deriving (GHC.Generic,Show,Eq,Ord,NFData)
1887−instance RenderSQL (TypeExpression schemas ty) where
1888− renderSQL = renderTypeExpression
1889−
1890−-- | The enum or composite type in a `Typedef` can be expressed by its alias.
1891−typedef
1892− :: (Has sch schemas schema, Has td schema ('Typedef ty))
1893− => QualifiedAlias sch td
1894− -> TypeExpression schemas (nullity ty)
1895−typedef = UnsafeTypeExpression . renderSQL
1896−
1897−-- | The composite type corresponding to a `Table` definition can be expressed
1898−-- by its alias.
1899−typetable
1900− :: (Has sch schemas schema, Has tab schema ('Table table))
1901− => QualifiedAlias sch tab
1902− -> TypeExpression schemas (nullity ('PGcomposite (TableToRow table)))
1903−typetable = UnsafeTypeExpression . renderSQL
1904−
1905−-- | The composite type corresponding to a `View` definition can be expressed
1906−-- by its alias.
1907−typeview
1908− :: (Has sch schemas schema, Has vw schema ('View view))
1909− => QualifiedAlias sch vw
1910− -> TypeExpression schemas (nullity ('PGcomposite view))
1911−typeview = UnsafeTypeExpression . renderSQL
1912−
1913−-- | logical Boolean (true/false)
1914−bool :: TypeExpression schemas (nullity 'PGbool)
1915−bool = UnsafeTypeExpression "bool"
1916−-- | signed two-byte integer
1917−int2, smallint :: TypeExpression schemas (nullity 'PGint2)
1918−int2 = UnsafeTypeExpression "int2"
1919−smallint = UnsafeTypeExpression "smallint"
1920−-- | signed four-byte integer
1921−int4, int, integer :: TypeExpression schemas (nullity 'PGint4)
1922−int4 = UnsafeTypeExpression "int4"
1923−int = UnsafeTypeExpression "int"
1924−integer = UnsafeTypeExpression "integer"
1925−-- | signed eight-byte integer
1926−int8, bigint :: TypeExpression schemas (nullity 'PGint8)
1927−int8 = UnsafeTypeExpression "int8"
1928−bigint = UnsafeTypeExpression "bigint"
1929−-- | arbitrary precision numeric type
1930−numeric :: TypeExpression schemas (nullity 'PGnumeric)
1931−numeric = UnsafeTypeExpression "numeric"
1932−-- | single precision floating-point number (4 bytes)
1933−float4, real :: TypeExpression schemas (nullity 'PGfloat4)
1934−float4 = UnsafeTypeExpression "float4"
1935−real = UnsafeTypeExpression "real"
1936−-- | double precision floating-point number (8 bytes)
1937−float8, doublePrecision :: TypeExpression schemas (nullity 'PGfloat8)
1938−float8 = UnsafeTypeExpression "float8"
1939−doublePrecision = UnsafeTypeExpression "double precision"
1940−-- | currency amount
1941−money :: TypeExpression schema (nullity 'PGmoney)
1942−money = UnsafeTypeExpression "money"
1943−-- | variable-length character string
1944−text :: TypeExpression schemas (nullity 'PGtext)
1945−text = UnsafeTypeExpression "text"
1946−-- | fixed-length character string
1947−char, character
1948− :: forall n schemas nullity. (KnownNat n, 1 <= n)
1949− => TypeExpression schemas (nullity ('PGchar n))
1950−char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"
1951−character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"
1952−-- | variable-length character string
1953−varchar, characterVarying
1954− :: forall n schemas nullity. (KnownNat n, 1 <= n)
1955− => TypeExpression schemas (nullity ('PGvarchar n))
1956−varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"
1957−characterVarying = UnsafeTypeExpression $
1958− "character varying(" <> renderNat @n <> ")"
1959−-- | binary data ("byte array")
1960−bytea :: TypeExpression schemas (nullity 'PGbytea)
1961−bytea = UnsafeTypeExpression "bytea"
1962−-- | date and time (no time zone)
1963−timestamp :: TypeExpression schemas (nullity 'PGtimestamp)
1964−timestamp = UnsafeTypeExpression "timestamp"
1965−-- | date and time, including time zone
1966−timestampWithTimeZone :: TypeExpression schemas (nullity 'PGtimestamptz)
1967−timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"
1968−-- | calendar date (year, month, day)
1969−date :: TypeExpression schemas (nullity 'PGdate)
1970−date = UnsafeTypeExpression "date"
1971−-- | time of day (no time zone)
1972−time :: TypeExpression schemas (nullity 'PGtime)
1973−time = UnsafeTypeExpression "time"
1974−-- | time of day, including time zone
1975−timeWithTimeZone :: TypeExpression schemas (nullity 'PGtimetz)
1976−timeWithTimeZone = UnsafeTypeExpression "time with time zone"
1977−-- | time span
1978−interval :: TypeExpression schemas (nullity 'PGinterval)
1979−interval = UnsafeTypeExpression "interval"
1980−-- | universally unique identifier
1981−uuid :: TypeExpression schemas (nullity 'PGuuid)
1982−uuid = UnsafeTypeExpression "uuid"
1983−-- | IPv4 or IPv6 host address
1984−inet :: TypeExpression schemas (nullity 'PGinet)
1985−inet = UnsafeTypeExpression "inet"
1986−-- | textual JSON data
1987−json :: TypeExpression schemas (nullity 'PGjson)
1988−json = UnsafeTypeExpression "json"
1989−-- | binary JSON data, decomposed
1990−jsonb :: TypeExpression schemas (nullity 'PGjsonb)
1991−jsonb = UnsafeTypeExpression "jsonb"
1992−-- | variable length array
1993−vararray
1994− :: TypeExpression schemas pg
1995− -> TypeExpression schemas (nullity ('PGvararray pg))
1996−vararray ty = UnsafeTypeExpression $ renderSQL ty <> "[]"
1997−-- | fixed length array
1998−--
1999−-- >>> renderSQL (fixarray @'[2] json)
2000−-- "json[2]"
2001−fixarray
2002− :: forall dims schemas nullity pg. SOP.All KnownNat dims
2003− => TypeExpression schemas pg
2004− -> TypeExpression schemas (nullity ('PGfixarray dims pg))
2005−fixarray ty = UnsafeTypeExpression $
2006− renderSQL ty <> renderDims @dims
2007− where
2008− renderDims :: forall ns. SOP.All KnownNat ns => ByteString
2009− renderDims =
2010− ("[" <>)
2011− . (<> "]")
2012− . ByteString.intercalate "]["
2013− . hcollapse
2014− $ hcmap (SOP.Proxy @KnownNat)
2015− (K . fromString . show . natVal)
2016− (hpure SOP.Proxy :: NP SOP.Proxy ns)
2017−
2018−-- | `pgtype` is a demoted version of a `PGType`
2019−class PGTyped schemas (ty :: NullityType) where
2020− pgtype :: TypeExpression schemas ty
2021−instance PGTyped schemas (nullity 'PGbool) where pgtype = bool
2022−instance PGTyped schemas (nullity 'PGint2) where pgtype = int2
2023−instance PGTyped schemas (nullity 'PGint4) where pgtype = int4
2024−instance PGTyped schemas (nullity 'PGint8) where pgtype = int8
2025−instance PGTyped schemas (nullity 'PGnumeric) where pgtype = numeric
2026−instance PGTyped schemas (nullity 'PGfloat4) where pgtype = float4
2027−instance PGTyped schemas (nullity 'PGfloat8) where pgtype = float8
2028−instance PGTyped schemas (nullity 'PGtext) where pgtype = text
2029−instance (KnownNat n, 1 <= n)
2030− => PGTyped schemas (nullity ('PGchar n)) where pgtype = char @n
2031−instance (KnownNat n, 1 <= n)
2032− => PGTyped schemas (nullity ('PGvarchar n)) where pgtype = varchar @n
2033−instance PGTyped schemas (nullity 'PGbytea) where pgtype = bytea
2034−instance PGTyped schemas (nullity 'PGtimestamp) where pgtype = timestamp
2035−instance PGTyped schemas (nullity 'PGtimestamptz) where pgtype = timestampWithTimeZone
2036−instance PGTyped schemas (nullity 'PGdate) where pgtype = date
2037−instance PGTyped schemas (nullity 'PGtime) where pgtype = time
2038−instance PGTyped schemas (nullity 'PGtimetz) where pgtype = timeWithTimeZone
2039−instance PGTyped schemas (nullity 'PGinterval) where pgtype = interval
2040−instance PGTyped schemas (nullity 'PGuuid) where pgtype = uuid
2041−instance PGTyped schemas (nullity 'PGjson) where pgtype = json
2042−instance PGTyped schemas (nullity 'PGjsonb) where pgtype = jsonb
2043−instance PGTyped schemas ty
2044− => PGTyped schemas (nullity ('PGvararray ty)) where
2045− pgtype = vararray (pgtype @schemas @ty)
2046−instance (SOP.All KnownNat dims, PGTyped schemas ty)
2047− => PGTyped schemas (nullity ('PGfixarray dims ty)) where
2048− pgtype = fixarray @dims (pgtype @schemas @ty)
2049−
2050−{-----------------------------------------
2051−Sorting
2052−-----------------------------------------}
2053−
2054−-- | `SortExpression`s are used by `orderBy` to optionally sort the results
2055−-- of a `Squeal.PostgreSQL.Query.Query`. `Asc` or `Desc`
2056−-- set the sort direction of a `NotNull` result
2057−-- column to ascending or descending. Ascending order puts smaller values
2058−-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,
2059−-- descending order is determined with the `.>` operator. `AscNullsFirst`,
2060−-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to
2061−-- determine whether nulls appear before or after non-null values in the sort
2062−-- ordering of a `Null` result column.
2063−data SortExpression outer grp commons schemas params from where
2064− Asc
2065− :: Expression outer grp commons schemas params from ('NotNull ty)
2066− -> SortExpression outer grp commons schemas params from
2067− Desc
2068− :: Expression outer grp commons schemas params from ('NotNull ty)
2069− -> SortExpression outer grp commons schemas params from
2070− AscNullsFirst
2071− :: Expression outer grp commons schemas params from ('Null ty)
2072− -> SortExpression outer grp commons schemas params from
2073− AscNullsLast
2074− :: Expression outer grp commons schemas params from ('Null ty)
2075− -> SortExpression outer grp commons schemas params from
2076− DescNullsFirst
2077− :: Expression outer grp commons schemas params from ('Null ty)
2078− -> SortExpression outer grp commons schemas params from
2079− DescNullsLast
2080− :: Expression outer grp commons schemas params from ('Null ty)
2081− -> SortExpression outer grp commons schemas params from
2082−deriving instance Show (SortExpression outer grp commons schemas params from)
2083−
2084−{- |
2085−The `orderBy` clause causes the result rows of a `Squeal.PostgreSQL.Query.TableExpression`
2086−to be sorted according to the specified `SortExpression`(s).
2087−If two rows are equal according to the leftmost expression,
2088−they are compared according to the next expression and so on.
2089−If they are equal according to all specified expressions,
2090−they are returned in an implementation-dependent order.
2091−
2092−You can also control the order in which rows are processed by window functions
2093−using `orderBy` within `Squeal.PostgreSQL.Query.Over`.
2094−-}
2095−class OrderBy expr where
2096− orderBy
2097− :: [SortExpression outer grp commons schemas params from]
2098− -> expr outer grp commons schemas params from
2099− -> expr outer grp commons schemas params from
2100−
2101−-- | Render a `SortExpression`.
2102−instance RenderSQL (SortExpression outer grp commons schemas params from) where
2103− renderSQL = \case
2104− Asc expression -> renderSQL expression <+> "ASC"
2105− Desc expression -> renderSQL expression <+> "DESC"
2106− AscNullsFirst expression -> renderSQL expression
2107− <+> "ASC NULLS FIRST"
2108− DescNullsFirst expression -> renderSQL expression
2109− <+> "DESC NULLS FIRST"
2110− AscNullsLast expression -> renderSQL expression <+> "ASC NULLS LAST"
2111− DescNullsLast expression -> renderSQL expression <+> "DESC NULLS LAST"
2112−
2113−-- | A `WindowDefinition` is a set of table rows that are somehow related
2114−-- to the current row
2115−data WindowDefinition outer grp commons schemas params from where
2116− WindowDefinition
2117− :: SListI bys
2118− => NP (Expression outer grp commons schemas params from) bys
2119− -> [SortExpression outer grp commons schemas params from]
2120− -> WindowDefinition outer grp commons schemas params from
2121−
2122−instance OrderBy WindowDefinition where
2123− orderBy sortsR (WindowDefinition parts sortsL)
2124− = WindowDefinition parts (sortsL ++ sortsR)
2125−
2126−instance RenderSQL (WindowDefinition outer commons schemas from grp params) where
2127− renderSQL (WindowDefinition part ord) =
2128− renderPartitionByClause part <> renderOrderByClause ord
2129− where
2130− renderPartitionByClause = \case
2131− Nil -> ""
2132− parts -> "PARTITION" <+> "BY" <+> renderCommaSeparated renderExpression parts
2133− renderOrderByClause = \case
2134− [] -> ""
2135− srts -> " ORDER" <+> "BY"
2136− <+> commaSeparated (renderSQL <$> srts)
2137−
2138−{- |
2139−The `partitionBy` clause within `Squeal.PostgreSQL.Query.Over` divides the rows into groups,
2140−or partitions, that share the same values of the `partitionBy` `Expression`(s).
2141−For each row, the window function is computed across the rows that fall into
2142−the same partition as the current row.
2143−-}
2144−partitionBy
2145− :: SListI bys
2146− => NP (Expression outer grp commons schemas params from) bys
2147− -> WindowDefinition outer grp commons schemas params from
2148−partitionBy bys = WindowDefinition bys []
2149−
2150−{- |
2151−A window function performs a calculation across a set of table rows
2152−that are somehow related to the current row. This is comparable to the type
2153−of calculation that can be done with an aggregate function.
2154−However, window functions do not cause rows to become grouped into a single
2155−output row like non-window aggregate calls would.
2156−Instead, the rows retain their separate identities.
2157−Behind the scenes, the window function is able to access more than
2158−just the current row of the query result.
2159−-}
2160−newtype WindowFunction
2161− (outer :: FromType)
2162− (grp :: Grouping)
2163− (commons :: FromType)
2164− (schemas :: SchemasType)
2165− (params :: [NullityType])
2166− (from :: FromType)
2167− (ty :: NullityType)
2168− = UnsafeWindowFunction { renderWindowFunction :: ByteString }
2169− deriving (GHC.Generic,Show,Eq,Ord,NFData)
2170−
2171−instance RenderSQL (WindowFunction outer grp commons schemas params from ty) where
2172− renderSQL = renderWindowFunction
2173−
2174−unsafeWindowFunction1
2175− :: ByteString
2176− -> Expression outer grp commons schemas params from ty0
2177− -> WindowFunction outer grp commons schemas params from ty1
2178−unsafeWindowFunction1 fun x
2179− = UnsafeWindowFunction $ fun <> parenthesized (renderSQL x)
2180−
2181−unsafeWindowFunction2
2182− :: ByteString
2183− -> (Expression outer grp commons schemas params from :*: Expression outer grp commons schemas params from) ty0
2184− -> WindowFunction outer grp commons schemas params from ty1
2185−unsafeWindowFunction2 fun (x :*: x')
2186− = UnsafeWindowFunction $ fun <> parenthesized (renderSQL x <> ", " <> renderSQL x')
2187−
2188−{- | rank of the current row with gaps; same as `rowNumber` of its first peer
2189−>>> printSQL rank
2190−rank()
2191−-}
2192−rank :: WindowFunction outer grp commons schemas params from ('NotNull 'PGint8)
2193−rank = UnsafeWindowFunction "rank()"
2194−
2195−{- | number of the current row within its partition, counting from 1
2196−>>> printSQL rowNumber
2197−row_number()
2198−-}
2199−rowNumber :: WindowFunction outer grp commons schemas params from ('NotNull 'PGint8)
2200−rowNumber = UnsafeWindowFunction "row_number()"
2201−
2202−{- | rank of the current row without gaps; this function counts peer groups
2203−>>> printSQL denseRank
2204−dense_rank()
2205−-}
2206−denseRank :: WindowFunction outer grp commons schemas params from ('NotNull 'PGint8)
2207−denseRank = UnsafeWindowFunction "dense_rank()"
2208−
2209−{- | relative rank of the current row: (rank - 1) / (total partition rows - 1)
2210−>>> printSQL percentRank
2211−percent_rank()
2212−-}
2213−percentRank :: WindowFunction outer grp commons schemas params from ('NotNull 'PGfloat8)
2214−percentRank = UnsafeWindowFunction "percent_rank()"
2215−
2216−{- | cumulative distribution: (number of partition rows
2217−preceding or peer with current row) / total partition rows
2218−>>> printSQL cumeDist
2219−cume_dist()
2220−-}
2221−cumeDist :: WindowFunction outer grp commons schemas params from ('NotNull 'PGfloat8)
2222−cumeDist = UnsafeWindowFunction "cume_dist()"
2223−
2224−{- | integer ranging from 1 to the argument value,
2225−dividing the partition as equally as possible
2226−-}
2227−ntile
2228− :: Expression outer grp commons schemas params from ('NotNull 'PGint4)
2229− -- ^ num buckets
2230− -> WindowFunction outer grp commons schemas params from ('NotNull 'PGint4)
2231−ntile = unsafeWindowFunction1 "ntile"
2232−
2233−{- | returns value evaluated at the row that is offset rows before the current
2234−row within the partition; if there is no such row, instead return default
2235−(which must be of the same type as value). Both offset and default are
2236−evaluated with respect to the current row.
2237−-}
2238−lag
2239− :: Expression outer grp commons schemas params from ty
2240− -- ^ value
2241− -> Expression outer grp commons schemas params from ('NotNull 'PGint4)
2242− -- ^ offset
2243− -> Expression outer grp commons schemas params from ty
2244− -- ^ default
2245− -> WindowFunction outer grp commons schemas params from ty
2246−lag value offset def = UnsafeWindowFunction $ "lag"
2247− <> parenthesized
2248− (commaSeparated ([renderSQL value, renderSQL offset, renderSQL def]))
2249−
2250−{- | returns value evaluated at the row that is offset rows after the current
2251−row within the partition; if there is no such row, instead return default
2252−(which must be of the same type as value). Both offset and default are
2253−evaluated with respect to the current row.
2254−-}
2255−lead
2256− :: Expression outer grp commons schemas params from ty
2257− -- ^ value
2258− -> Expression outer grp commons schemas params from ('NotNull 'PGint4)
2259− -- ^ offset
2260− -> Expression outer grp commons schemas params from ty
2261− -- ^ default
2262− -> WindowFunction outer grp commons schemas params from ty
2263−lead value offset def = UnsafeWindowFunction $ "lag"
2264− <> parenthesized
2265− (commaSeparated ([renderSQL value, renderSQL offset, renderSQL def]))
2266−
2267−{- | returns value evaluated at the row that is the
2268−first row of the window frame
2269−-}
2270−firstValue
2271− :: Expression outer grp commons schemas params from ty
2272− -- ^ value
2273− -> WindowFunction outer grp commons schemas params from ty
2274−firstValue = unsafeWindowFunction1 "first_value"
2275−
2276−{- | returns value evaluated at the row that is the
2277−last row of the window frame
2278−-}
2279−lastValue
2280− :: Expression outer grp commons schemas params from ty
2281− -- ^ value
2282− -> WindowFunction outer grp commons schemas params from ty
2283−lastValue = unsafeWindowFunction1 "last_value"
2284−
2285−{- | returns value evaluated at the row that is the nth
2286−row of the window frame (counting from 1); null if no such row
2287−-}
2288−nthValue
2289− :: Expression outer grp commons schemas params from (nullity ty)
2290− -- ^ value
2291− -> Expression outer grp commons schemas params from ('NotNull 'PGint4)
2292− -- ^ nth
2293− -> WindowFunction outer grp commons schemas params from ('Null ty)
2294−nthValue value nth = UnsafeWindowFunction $ "nth_value"
2295− <> parenthesized (commaSeparated [renderSQL value, renderSQL nth])
2296−
2297−{-|
2298−Create date from year, month and day fields
2299−
2300−>>> printSQL (makeDate 1984 7 3)
2301−make_date(1984, 7, 3)
2302−-}
2303−makeDate
2304− :: Expression outer grp commons schemas params from (nullity 'PGint4)
2305− -- ^ year
2306− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2307− -- ^ month
2308− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2309− -- ^ day
2310− -> Expression outer grp commons schemas params from (nullity 'PGdate)
2311−makeDate y m d = UnsafeExpression $ "make_date" <>
2312− parenthesized (renderCommaSeparated renderSQL (y :* m :* d :* Nil))
2313−
2314−{-|
2315−Create time from hour, minute and seconds fields
2316−
2317−>>> printSQL (makeTime 8 15 23.5)
2318−make_time(8, 15, 23.5)
2319−-}
2320−makeTime
2321− :: Expression outer grp commons schemas params from (nullity 'PGint4)
2322− -- ^ hour
2323− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2324− -- ^ min
2325− -> Expression outer grp commons schemas params from (nullity 'PGfloat8)
2326− -- ^ sec
2327− -> Expression outer grp commons schemas params from (nullity 'PGtime)
2328−makeTime h m s = UnsafeExpression $ "make_time" <>
2329− parenthesized (renderCommaSeparated renderSQL (h :* m :* s :* Nil))
2330−
2331−{-|
2332−Create timestamp from year, month, day, hour, minute and seconds fields
2333−
2334−>>> printSQL (makeTimestamp 2013 7 15 8 15 23.5)
2335−make_timestamp(2013, 7, 15, 8, 15, 23.5)
2336−-}
2337−makeTimestamp
2338− :: Expression outer grp commons schemas params from (nullity 'PGint4)
2339− -- ^ year
2340− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2341− -- ^ month
2342− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2343− -- ^ day
2344− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2345− -- ^ hour
2346− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2347− -- ^ min
2348− -> Expression outer grp commons schemas params from (nullity 'PGfloat8)
2349− -- ^ sec
2350− -> Expression outer grp commons schemas params from (nullity 'PGtimestamp)
2351−makeTimestamp y mon d h m s =
2352− UnsafeExpression $ "make_timestamp" <> parenthesized
2353− (renderCommaSeparated renderSQL (y :* mon :* d :* h :* m :* s :* Nil))
2354−
2355−{-|
2356−Create timestamp with time zone from
2357−year, month, day, hour, minute and seconds fields;
2358−the current time zone is used
2359−
2360−>>> printSQL (makeTimestamptz 2013 7 15 8 15 23.5)
2361−make_timestamptz(2013, 7, 15, 8, 15, 23.5)
2362−-}
2363−makeTimestamptz
2364− :: Expression outer grp commons schemas params from (nullity 'PGint4)
2365− -- ^ year
2366− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2367− -- ^ month
2368− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2369− -- ^ day
2370− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2371− -- ^ hour
2372− -> Expression outer grp commons schemas params from (nullity 'PGint4)
2373− -- ^ min
2374− -> Expression outer grp commons schemas params from (nullity 'PGfloat8)
2375− -- ^ sec
2376− -> Expression outer grp commons schemas params from (nullity 'PGtimestamptz)
2377−makeTimestamptz y mon d h m s =
2378− UnsafeExpression $ "make_timestamptz" <> parenthesized
2379− (renderCommaSeparated renderSQL (y :* mon :* d :* h :* m :* s :* Nil))
2380−
2381−{-|
2382−Affine space operations on time types.
2383−-}
2384−class TimeOp time diff | time -> diff where
2385− {-|
2386− >>> printSQL (makeDate 1984 7 3 !+ 365)
2387− (make_date(1984, 7, 3) + 365)
2388− -}
2389− (!+)
2390− :: Expression outer grp commons schemas params from (nullity time)
2391− -> Expression outer grp commons schemas params from (nullity diff)
2392− -> Expression outer grp commons schemas params from (nullity time)
2393− (!+) = unsafeBinaryOp "+"
2394− {-|
2395− >>> printSQL (365 +! makeDate 1984 7 3)
2396− (365 + make_date(1984, 7, 3))
2397− -}
2398− (+!)
2399− :: Expression outer grp commons schemas params from (nullity diff)
2400− -> Expression outer grp commons schemas params from (nullity time)
2401− -> Expression outer grp commons schemas params from (nullity time)
2402− (+!) = unsafeBinaryOp "+"
2403− {-|
2404− >>> printSQL (makeDate 1984 7 3 !- 365)
2405− (make_date(1984, 7, 3) - 365)
2406− -}
2407− (!-)
2408− :: Expression outer grp commons schemas params from (nullity time)
2409− -> Expression outer grp commons schemas params from (nullity diff)
2410− -> Expression outer grp commons schemas params from (nullity time)
2411− (!-) = unsafeBinaryOp "-"
2412− {-|
2413− >>> printSQL (makeDate 1984 7 3 !-! currentDate)
2414− (make_date(1984, 7, 3) - CURRENT_DATE)
2415− -}
2416− (!-!)
2417− :: Expression outer grp commons schemas params from (nullity time)
2418− -> Expression outer grp commons schemas params from (nullity time)
2419− -> Expression outer grp commons schemas params from (nullity diff)
2420− (!-!) = unsafeBinaryOp "-"
2421−instance TimeOp 'PGtimestamp 'PGinterval
2422−instance TimeOp 'PGtimestamptz 'PGinterval
2423−instance TimeOp 'PGtime 'PGinterval
2424−instance TimeOp 'PGtimetz 'PGinterval
2425−instance TimeOp 'PGinterval 'PGinterval
2426−instance TimeOp 'PGdate 'PGint4
squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hsnew file+462
@@ -0,0 +1,462 @@
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.hsnew file+169
@@ -0,0 +1,169 @@
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.hsnew file+206
@@ -0,0 +1,206 @@
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.hsnew file+462
@@ -0,0 +1,462 @@
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.hsnew file+87
@@ -0,0 +1,87 @@
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.hsnew file+105
@@ -0,0 +1,105 @@
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.hsnew file+100
@@ -0,0 +1,100 @@
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.hsnew file+104
@@ -0,0 +1,104 @@
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.hsnew file+80
@@ -0,0 +1,80 @@
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.hsnew file+230
@@ -0,0 +1,230 @@
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.hsnew file+139
@@ -0,0 +1,139 @@
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.hsnew file+85
@@ -0,0 +1,85 @@
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.hsnew file+120
@@ -0,0 +1,120 @@
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.hsnew file+64
@@ -0,0 +1,64 @@
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.hsnew file+157
@@ -0,0 +1,157 @@
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.hsnew file+192
@@ -0,0 +1,192 @@
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.hsnew file+446
@@ -0,0 +1,446 @@
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.hsnew file+284
@@ -0,0 +1,284 @@
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.hsnew file+112
@@ -0,0 +1,112 @@
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+170−177
@@ -18,6 +18,7 @@ Squeal data manipulation language.
1818 , MultiParamTypeClasses
1919 , OverloadedStrings
2020 , PatternSynonyms
21+ , QuantifiedConstraints
2122 , RankNTypes
2223 , ScopedTypeVariables
2324 , TypeApplications
@@ -29,19 +30,9 @@ Squeal data manipulation language.
2930
3031module Squeal.PostgreSQL.Manipulation
3132 ( -- * Manipulation
32− Manipulation (..)
33− , Manipulation_
33+ Manipulation_
34+ , Manipulation (..)
3435 , queryStatement
35− , QueryClause (..)
36− , pattern Values_
37− , DefaultAliasable (..)
38− , ColumnExpression (..)
39− , ReturningClause (..)
40− , pattern Returning_
41− , ConflictClause (..)
42− , ConflictTarget (..)
43− , ConflictAction (..)
44− , UsingClause (..)
4536 -- * Insert
4637 , insertInto
4738 , insertInto_
@@ -51,37 +42,95 @@ module Squeal.PostgreSQL.Manipulation
5142 -- * Delete
5243 , deleteFrom
5344 , deleteFrom_
54− , also
45+ -- * Clauses
46+ , Optional (..)
47+ , QueryClause (..)
48+ , pattern Values_
49+ , ReturningClause (..)
50+ , pattern Returning_
51+ , ConflictClause (..)
52+ , ConflictTarget (..)
53+ , ConflictAction (..)
54+ , UsingClause (..)
5555 ) where
5656
5757import Control.DeepSeq
5858import Data.ByteString hiding (foldr)
5959import Data.Kind (Type)
60−import GHC.TypeLits (KnownSymbol)
6160
6261import qualified Generics.SOP as SOP
6362import qualified GHC.Generics as GHC
6463
65−import Squeal.PostgreSQL.Binary
64+import Squeal.PostgreSQL.Alias
6665import Squeal.PostgreSQL.Expression
66+import Squeal.PostgreSQL.Expression.Logic
67+import Squeal.PostgreSQL.List
68+import Squeal.PostgreSQL.PG
6769import Squeal.PostgreSQL.Render
6870import Squeal.PostgreSQL.Query
6971import Squeal.PostgreSQL.Schema
7072
73+-- $setup
74+-- >>> import Squeal.PostgreSQL
75+-- >>> import Data.Int
76+-- >>> import Data.Time
77+
7178{- |
7279A `Manipulation` is a statement which may modify data in the database,
7380but does not alter its schemas. Examples are inserts, updates and deletes.
7481A `Query` is also considered a `Manipulation` even though it does not modify data.
7582
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+
76125simple insert:
77126
78127>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]
79128>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
80129>>> :{
81130let
82− manipulation :: Manipulation '[] (Public Schema) '[] '[]
131+ manipulation :: Manipulation_ (Public Schema) () ()
83132 manipulation =
84− insertInto_ #tab (Values_ (2 `as` #col1 :* defaultAs #col2))
133+ insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))
85134in printSQL manipulation
86135:}
87136INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)
@@ -92,9 +141,9 @@ parameterized insert:
92141>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
93142>>> :{
94143let
95− manipulation :: Manipulation '[] (Public Schema) '[ 'NotNull 'PGint4, 'NotNull 'PGint4 ] '[]
144+ manipulation :: Manipulation_ (Public Schema) (Int32, Int32) ()
96145 manipulation =
97− insertInto_ #tab (Values_ (param @1 `as` #col1 :* param @2 `as` #col2))
146+ insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))
98147in printSQL manipulation
99148:}
100149INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))
@@ -103,9 +152,9 @@ returning insert:
103152
104153>>> :{
105154let
106− manipulation :: Manipulation '[] (Public Schema) '[] '["fromOnly" ::: 'NotNull 'PGint4]
155+ manipulation :: Manipulation_ (Public Schema) () (Only Int32)
107156 manipulation =
108− insertInto #tab (Values_ (2 `as` #col1 :* 3 `as` #col2))
157+ insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))
109158 OnConflictDoRaise (Returning (#col1 `as` #fromOnly))
110159in printSQL manipulation
111160:}
@@ -118,12 +167,12 @@ upsert:
118167>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]
119168>>> :{
120169let
121− manipulation :: Manipulation '[] (Public CustomersSchema) '[] '[]
170+ manipulation :: Manipulation_ (Public CustomersSchema) () ()
122171 manipulation =
123172 insertInto #customers
124− (Values_ ("John Smith" `as` #name :* "john@smith.com" `as` #email))
173+ (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))
125174 (OnConflict (OnConstraint #uq)
126− (DoUpdate (((#excluded ! #email) <> "; " <> (#customers ! #email)) `as` #email) []))
175+ (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))
127176 (Returning_ Nil)
128177in printSQL manipulation
129178:}
@@ -133,7 +182,7 @@ query insert:
133182
134183>>> :{
135184let
136− manipulation :: Manipulation '[] (Public Schema) '[] '[]
185+ manipulation :: Manipulation_ (Public Schema) () ()
137186 manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))
138187in printSQL manipulation
139188:}
@@ -143,8 +192,8 @@ update:
143192
144193>>> :{
145194let
146− manipulation :: Manipulation '[] (Public Schema) '[] '[]
147− manipulation = update_ #tab (2 `as` #col1) (#col1 ./= #col2)
195+ manipulation :: Manipulation_ (Public Schema) () ()
196+ manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)
148197in printSQL manipulation
149198:}
150199UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")
@@ -153,9 +202,7 @@ delete:
153202
154203>>> :{
155204let
156− manipulation :: Manipulation '[] (Public Schema) '[]
157− '[ "col1" ::: 'NotNull 'PGint4
158− , "col2" ::: 'NotNull 'PGint4 ]
205+ manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)
159206 manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)
160207in printSQL manipulation
161208:}
@@ -166,13 +213,13 @@ delete and using clause:
166213>>> :{
167214type Schema3 =
168215 '[ "tab" ::: 'Table ('[] :=> Columns)
169− , "other_tab" ::: 'Table ('[] :=> Columns)
170− , "third_tab" ::: 'Table ('[] :=> Columns) ]
216+ , "other_tab" ::: 'Table ('[] :=> Columns)
217+ , "third_tab" ::: 'Table ('[] :=> Columns) ]
171218:}
172219
173220>>> :{
174221let
175− manipulation :: Manipulation '[] (Public Schema3) '[] '[]
222+ manipulation :: Manipulation_ (Public Schema3) () ()
176223 manipulation =
177224 deleteFrom #tab (Using (table #other_tab & also (table #third_tab)))
178225 ( (#tab ! #col2 .== #other_tab ! #col2)
@@ -188,7 +235,7 @@ with manipulation:
188235>>> type ProductsSchema = '["products" ::: 'Table ('[] :=> ProductsColumns), "products_deleted" ::: 'Table ('[] :=> ProductsColumns)]
189236>>> :{
190237let
191− manipulation :: Manipulation '[] (Public ProductsSchema) '[ 'NotNull 'PGdate] '[]
238+ manipulation :: Manipulation_ (Public ProductsSchema) (Only Day) ()
192239 manipulation = with
193240 (deleteFrom #products NoUsing (#date .< param @1) (Returning Star) `as` #del)
194241 (insertInto_ #products_deleted (Subquery (select Star (from (common #del)))))
@@ -196,26 +243,13 @@ in printSQL manipulation
196243:}
197244WITH "del" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "del" AS "del"
198245-}
199−newtype Manipulation
200− (commons :: FromType)
201− (schemas :: SchemasType)
202− (params :: [NullityType])
203− (columns :: RowType)
204− = UnsafeManipulation { renderManipulation :: ByteString }
205− deriving (GHC.Generic,Show,Eq,Ord,NFData)
206−instance RenderSQL (Manipulation commons schemas params columns) where
207− renderSQL = renderManipulation
208−instance With Manipulation where
209− with Done manip = manip
210− with ctes manip = UnsafeManipulation $
211− "WITH" <+> renderSQL ctes <+> renderSQL manip
212−
213246type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where
214247 Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)
215248
216249-- | Convert a `Query` into a `Manipulation`.
217250queryStatement
218251 :: Query '[] commons schemas params columns
252+ -- ^ `Query` to embed as a `Manipulation`
219253 -> Manipulation commons schemas params columns
220254queryStatement q = UnsafeManipulation $ renderSQL q
221255
@@ -238,9 +272,13 @@ insertInto
238272 , SOP.SListI columns
239273 , SOP.SListI row1 )
240274 => QualifiedAlias sch tab
275+ -- ^ table
241276 -> QueryClause commons schemas params columns
277+ -- ^ what to insert
242278 -> ConflictClause tab commons schemas params table
279+ -- ^ what to do in case of conflict
243280 -> ReturningClause commons schemas params '[tab ::: row0] row1
281+ -- ^ what to return
244282 -> Manipulation commons schemas params row1
245283insertInto tab qry conflict ret = UnsafeManipulation $
246284 "INSERT" <+> "INTO" <+> renderSQL tab
@@ -248,6 +286,7 @@ insertInto tab qry conflict ret = UnsafeManipulation $
248286 <> renderSQL conflict
249287 <> renderSQL ret
250288
289+-- | Like `insertInto` but with `OnConflictDoRaise` and `no` `ReturningClause`.
251290insertInto_
252291 :: ( Has sch schemas schema
253292 , Has tab schema ('Table table)
@@ -255,25 +294,33 @@ insertInto_
255294 , row ~ TableToRow table
256295 , SOP.SListI columns )
257296 => QualifiedAlias sch tab
297+ -- ^ table
258298 -> QueryClause commons schemas params columns
299+ -- ^ what to insert
259300 -> Manipulation commons schemas params '[]
260301insertInto_ tab qry =
261302 insertInto tab qry OnConflictDoRaise (Returning_ Nil)
262303
304+-- | A `QueryClause` describes what to `insertInto` a table.
263305data QueryClause commons schemas params columns where
264306 Values
265307 :: SOP.SListI columns
266− => NP (ColumnExpression 'Ungrouped schemas params '[]) columns
267− -> [NP (ColumnExpression 'Ungrouped schemas params '[]) 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
268312 -> QueryClause commons schemas params columns
269313 Select
270314 :: SOP.SListI columns
271− => NP (ColumnExpression grp schemas params from) columns
272− -> TableExpression '[] grp commons schemas params from
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
273319 -> QueryClause commons schemas params columns
274320 Subquery
275321 :: ColumnsToRow columns ~ row
276322 => Query '[] commons schemas params row
323+ -- ^ subquery to insert
277324 -> QueryClause commons schemas params columns
278325
279326instance RenderSQL (QueryClause commons schemas params columns) where
@@ -292,109 +339,41 @@ instance RenderSQL (QueryClause commons schemas params columns) where
292339 Subquery qry -> renderQuery qry
293340 where
294341 renderSQLPartMaybe, renderValuePartMaybe
295− :: ColumnExpression grp schemas params from column -> Maybe ByteString
342+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
343+ -> Maybe ByteString
296344 renderSQLPartMaybe = \case
297− DefaultAs _ -> Nothing
298− Specific (_ `As` name) -> Just $ renderSQL name
345+ Default `As` _ -> Nothing
346+ Set _ `As` name -> Just $ renderSQL name
299347 renderValuePartMaybe = \case
300− DefaultAs _ -> Nothing
301− Specific (value `As` _) -> Just $ renderExpression value
348+ Default `As` _ -> Nothing
349+ Set value `As` _ -> Just $ renderExpression value
302350 renderSQLPart, renderValuePart
303− :: ColumnExpression grp schemas params from column -> ByteString
304− renderSQLPart = \case
305− DefaultAs name -> renderSQL name
306− Specific (_ `As` name) -> renderSQL name
307− renderValuePart = \case
308− DefaultAs _ -> "DEFAULT"
309− Specific (value `As` _) -> renderExpression value
351+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column
352+ -> ByteString
353+ renderSQLPart (_ `As` name) = renderSQL name
354+ renderValuePart (value `As` _) = renderSQL value
310355
356+-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s
357+-- whose `ColumnsType` must match the tables'.
311358pattern Values_
312359 :: SOP.SListI columns
313− => NP (ColumnExpression 'Ungrouped schemas params '[]) columns
360+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns
361+ -- ^ row of values
314362 -> QueryClause commons schemas params columns
315363pattern Values_ vals = Values vals []
316364
317−data ColumnExpression grp schemas params from column where
318− DefaultAs
319− :: KnownSymbol col
320− => Alias col
321− -> ColumnExpression grp schemas params from (col ::: 'Def :=> ty)
322− Specific
323− :: Aliased (Expression '[] grp '[] schemas params from) (col ::: ty)
324− -> ColumnExpression grp schemas params from (col ::: defness :=> ty)
325−
326−instance (KnownSymbol col, column ~ (col ::: defness :=> ty))
327− => Aliasable col
328− (Expression '[] grp '[] schemas params from ty)
329− (ColumnExpression grp schemas params from column) where
330− expression `as` col = Specific (expression `As` col)
331−instance (KnownSymbol col, columns ~ '[col ::: defness :=> ty])
332− => Aliasable col
333− (Expression '[] grp '[] schemas params from ty)
334− (NP (ColumnExpression grp schemas params from) columns) where
335− expression `as` col = expression `as` col :* Nil
336−instance (KnownSymbol col, column ~ (col ::: 'Def :=> ty))
337− => DefaultAliasable col (ColumnExpression grp schemas params from column) where
338− defaultAs = DefaultAs
339−instance (KnownSymbol col, columns ~ '[col ::: 'Def :=> ty])
340− => DefaultAliasable col (NP (ColumnExpression grp schemas params from) columns) where
341− defaultAs col = defaultAs col :* Nil
342−
343−instance (HasUnique tab from row, Has col row ty, column ~ (col ::: defness :=> ty))
344− => IsLabel col (ColumnExpression 'Ungrouped schemas params from column) where
345− fromLabel = fromLabel @col `as` Alias
346−instance (HasUnique tab from row, Has col row ty, columns ~ '[col ::: defness :=> ty])
347− => IsLabel col
348− (NP (ColumnExpression 'Ungrouped schemas params from) columns) where
349− fromLabel = fromLabel @col `as` Alias
350−
351−instance (Has tab from row, Has col row ty, column ~ (col ::: defness :=> ty))
352− => IsQualified tab col (ColumnExpression 'Ungrouped schemas params from column) where
353− tab ! col = tab ! col `as` col
354−instance (Has tab from row, Has col row ty, columns ~ '[col ::: defness :=> ty])
355− => IsQualified tab col (NP (ColumnExpression 'Ungrouped schemas params from) columns) where
356− tab ! col = tab ! col `as` col
357−
358−instance
359− ( HasUnique tab from row
360− , Has col row ty
361− , GroupedBy tab col bys
362− , column ~ (col ::: defness :=> ty)
363− ) => IsLabel col
364− (ColumnExpression ('Grouped bys) schemas params from column) where
365− fromLabel = fromLabel @col `as` Alias
366−instance
367− ( HasUnique tab from row
368− , Has col row ty
369− , GroupedBy tab col bys
370− , columns ~ '[col ::: defness :=> ty]
371− ) => IsLabel col
372− (NP (ColumnExpression ('Grouped bys) schemas params from) columns) where
373− fromLabel = fromLabel @col `as` Alias
374−
375−instance
376− ( Has tab from row
377− , Has col row ty
378− , GroupedBy tab col bys
379− , column ~ (col ::: defness :=> ty)
380− ) => IsQualified tab col
381− (ColumnExpression ('Grouped bys) schemas params from column) where
382− tab ! col = tab ! col `as` col
383−instance
384− ( Has tab from row
385− , Has col row ty
386− , GroupedBy tab col bys
387− , columns ~ '[col ::: defness :=> ty]
388− ) => IsQualified tab col
389− (NP (ColumnExpression ('Grouped bys) schemas params from) columns) where
390− tab ! col = tab ! col :* Nil
391−
392−instance RenderSQL (ColumnExpression grp schemas params from column) where
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
393374 renderSQL = \case
394− DefaultAs col ->
395− renderSQL col <+> "=" <+> "DEFAULT"
396− Specific (expression `As` col) ->
397− renderSQL col <+> "=" <+> renderSQL expression
375+ Default -> "DEFAULT"
376+ Set expr -> renderSQL expr
398377
399378-- | A `ReturningClause` computes and return value(s) based
400379-- on each row actually inserted, updated or deleted. This is primarily
@@ -404,19 +383,21 @@ instance RenderSQL (ColumnExpression grp schemas params from column) where
404383-- deleted will be returned. For example, if a row was locked
405384-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,
406385-- the row will not be returned. `Returning` `Star` will return all columns
407−-- in the row. Use @Returning Nil@ in the common case where no return
386+-- in the row. Use `Returning` `Nil` in the common case where no return
408387-- values are desired.
409388newtype ReturningClause commons schemas params from row =
410− Returning (Selection '[] 'Ungrouped commons schemas params from row)
389+ Returning (Selection '[] commons 'Ungrouped schemas params from row)
411390
412391instance RenderSQL (ReturningClause commons schemas params from row) where
413392 renderSQL = \case
414393 Returning (List Nil) -> ""
415394 Returning selection -> " RETURNING" <+> renderSQL selection
416395
396+-- | `Returning` a `List`
417397pattern Returning_
418398 :: SOP.SListI row
419− => NP (Aliased (Expression '[] 'Ungrouped commons schemas params from)) row
399+ => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row
400+ -- ^ row of values
420401 -> ReturningClause commons schemas params from row
421402pattern Returning_ list = Returning (List list)
422403
@@ -429,7 +410,9 @@ data ConflictClause tab commons schemas params table where
429410 OnConflictDoRaise :: ConflictClause tab commons schemas params table
430411 OnConflict
431412 :: ConflictTarget constraints
413+ -- ^ conflict target
432414 -> ConflictAction tab commons schemas params columns
415+ -- ^ conflict action
433416 -> ConflictClause tab commons schemas params (constraints :=> columns)
434417
435418-- | Render a `ConflictClause`.
@@ -440,6 +423,17 @@ instance SOP.SListI (TableToColumns table)
440423 OnConflict target action -> " ON CONFLICT"
441424 <+> renderSQL target <+> renderSQL action
442425
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+-}
443437data ConflictAction tab commons schemas params columns where
444438 DoNothing :: ConflictAction tab commons schemas params columns
445439 DoUpdate
@@ -448,8 +442,9 @@ data ConflictAction tab commons schemas params columns where
448442 , columns ~ (col0 ': cols)
449443 , SOP.All (HasIn columns) subcolumns
450444 , AllUnique subcolumns )
451− => NP (ColumnExpression 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]) subcolumns
452− -> [Condition '[] 'Ungrouped commons schemas params '[tab ::: row, "excluded" ::: row]]
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
453448 -> ConflictAction tab commons schemas params columns
454449
455450instance RenderSQL (ConflictAction tab commons schemas params columns) where
@@ -457,11 +452,17 @@ instance RenderSQL (ConflictAction tab commons schemas params columns) where
457452 DoNothing -> "DO NOTHING"
458453 DoUpdate updates whs'
459454 -> "DO UPDATE SET"
460− <+> renderCommaSeparated renderSQL updates
455+ <+> renderCommaSeparated renderUpdate updates
461456 <> case whs' of
462457 [] -> ""
463458 wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)
464459
460+renderUpdate
461+ :: (forall x. RenderSQL (expr x))
462+ => Aliased (Optional expr) ty
463+ -> ByteString
464+renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr
465+
465466-- | A `ConflictTarget` specifies the constraint violation that triggers a
466467-- `ConflictAction`.
467468data ConflictTarget constraints where
@@ -484,7 +485,6 @@ UPDATE statements
484485update
485486 :: ( SOP.SListI columns
486487 , SOP.SListI row1
487− , db ~ (commons :=> schemas)
488488 , Has sch schemas schema
489489 , Has tab schema ('Table table)
490490 , row0 ~ TableToRow table
@@ -492,9 +492,9 @@ update
492492 , SOP.All (HasIn columns) subcolumns
493493 , AllUnique subcolumns )
494494 => QualifiedAlias sch tab -- ^ table to update
495− -> NP (ColumnExpression 'Ungrouped schemas params '[tab ::: row0]) subcolumns
495+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns
496496 -- ^ modified values to replace old values
497− -> Condition '[] 'Ungrouped commons schemas params '[tab ::: row0]
497+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]
498498 -- ^ condition under which to perform update on a row
499499 -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
500500 -> Manipulation commons schemas params row1
@@ -502,14 +502,13 @@ update tab columns wh returning = UnsafeManipulation $
502502 "UPDATE"
503503 <+> renderSQL tab
504504 <+> "SET"
505− <+> renderCommaSeparated renderSQL columns
505+ <+> renderCommaSeparated renderUpdate columns
506506 <+> "WHERE" <+> renderSQL wh
507507 <> renderSQL returning
508508
509509-- | Update a row returning `Nil`.
510510update_
511511 :: ( SOP.SListI columns
512− , db ~ (commons :=> schemas)
513512 , Has sch schemas schema
514513 , Has tab schema ('Table table)
515514 , row ~ TableToRow table
@@ -517,9 +516,9 @@ update_
517516 , SOP.All (HasIn columns) subcolumns
518517 , AllUnique subcolumns )
519518 => QualifiedAlias sch tab -- ^ table to update
520− -> NP (ColumnExpression 'Ungrouped schemas params '[tab ::: row]) subcolumns
519+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns
521520 -- ^ modified values to replace old values
522− -> Condition '[] 'Ungrouped commons schemas params '[tab ::: row]
521+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
523522 -- ^ condition under which to perform update on a row
524523 -> Manipulation commons schemas params '[]
525524update_ tab columns wh = update tab columns wh (Returning_ Nil)
@@ -528,23 +527,32 @@ update_ tab columns wh = update tab columns wh (Returning_ Nil)
528527DELETE statements
529528-----------------------------------------}
530529
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.
531539data UsingClause commons schemas params from where
532540 NoUsing :: UsingClause commons schemas params '[]
533541 Using
534542 :: FromClause '[] commons schemas params from
543+ -- ^ what to use
535544 -> UsingClause commons schemas params from
536545
537546-- | Delete rows from a table.
538547deleteFrom
539548 :: ( SOP.SListI row1
540− , db ~ (commons :=> schemas)
541549 , Has sch schemas schema
542550 , Has tab schema ('Table table)
543551 , row0 ~ TableToRow table
544552 , columns ~ TableToColumns table )
545553 => QualifiedAlias sch tab -- ^ table to delete from
546554 -> UsingClause commons schemas params from
547− -> Condition '[] 'Ungrouped commons schemas params (tab ::: row0 ': from)
555+ -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)
548556 -- ^ condition under which to delete a row
549557 -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return
550558 -> Manipulation commons schemas params row1
@@ -559,27 +567,12 @@ deleteFrom tab using wh returning = UnsafeManipulation $
559567
560568-- | Delete rows returning `Nil`.
561569deleteFrom_
562− :: ( db ~ (commons :=> schemas)
563− , Has sch schemas schema
570+ :: ( Has sch schemas schema
564571 , Has tab schema ('Table table)
565572 , row ~ TableToRow table
566573 , columns ~ TableToColumns table )
567574 => QualifiedAlias sch tab -- ^ table to delete from
568− -> Condition '[] 'Ungrouped commons schemas params '[tab ::: row]
575+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]
569576 -- ^ condition under which to delete a row
570577 -> Manipulation commons schemas params '[]
571578deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)
572−
573−-- | This has the behaviour of a cartesian product, taking all
574−-- possible combinations between @left@ and @right@ - exactly like a
575−-- `crossJoin`. Used when no `crossJoin` syntax is required but simply
576−-- a comma separated list of tables. Typical case is the `UsingClause`
577−-- of a `deleteFrom` query.
578−also
579− :: FromClause outer commons schemas params right
580− -- ^ right
581− -> FromClause outer commons schemas params left
582− -- ^ left
583− -> FromClause outer commons schemas params (Join left right)
584−also right left = UnsafeFromClause $
585− renderSQL left <> "," <+> renderSQL right
squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+337−186
@@ -8,8 +8,13 @@ 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+
1113>>> :set -XDataKinds -XOverloadedLabels
1214>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators
15+
16+Next, let's define our `TableType`s.
17+
1318>>> :{
1419type UsersTable =
1520 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
@@ -20,7 +25,7 @@ type UsersTable =
2025
2126>>> :{
2227type EmailsTable =
23− '[ "pk_emails" ::: 'PrimaryKey '["id"]
28+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
2429 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
2530 ] :=>
2631 '[ "id" ::: 'Def :=> 'NotNull 'PGint4
@@ -29,227 +34,293 @@ type EmailsTable =
2934 ]
3035:}
3136
37+Now we can define some `Migration`s to make our tables.
38+
3239>>> :{
3340let
34− makeUsers :: Migration IO (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]
41+ makeUsers :: Migration Definition (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]
3542 makeUsers = Migration
3643 { name = "make users table"
37− , up = void . define $
38− createTable #users
44+ , up = createTable #users
3945 ( serial `as` #id :*
40− (text & notNullable) `as` #name )
46+ notNullable text `as` #name )
4147 ( primaryKey #id `as` #pk_users )
42− , down = void . define $ dropTable #users
48+ , down = dropTable #users
4349 }
4450:}
4551
4652>>> :{
4753let
48− makeEmails :: Migration IO '["public" ::: '["users" ::: 'Table UsersTable]]
54+ makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]
4955 '["public" ::: '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]]
5056 makeEmails = Migration
5157 { name = "make emails table"
52− , up = void . define $
53− createTable #emails
58+ , up = createTable #emails
5459 ( serial `as` #id :*
55− (int & notNullable) `as` #user_id :*
56− (text & nullable) `as` #email )
60+ notNullable int `as` #user_id :*
61+ nullable text `as` #email )
5762 ( primaryKey #id `as` #pk_emails :*
5863 foreignKey #user_id #users #id
5964 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
60− , down = void . define $ dropTable #emails
65+ , down = dropTable #emails
6166 }
6267:}
6368
64−Now that we have a couple migrations we can chain them together.
69+Now that we have a couple migrations we can chain them together into a `Path`.
6570
6671>>> let migrations = makeUsers :>> makeEmails :>> Done
6772
68−>>> :{
69−let
70− numMigrations
71− :: Has "migrations" schemas MigrationsSchema
72− => PQ schemas schemas IO ()
73− numMigrations = do
74− result <- runQuery (select Star (from (table (#migrations ! #schema_migrations `as` #m))))
75− num <- ntuples result
76− liftBase $ print num
77−:}
73+Now run the migrations.
7874
75+>>> import Control.Monad.IO.Class
7976>>> :{
8077withConnection "host=localhost port=5432 dbname=exampledb" $
8178 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
8279 -- suppress notices
80+ & pqThen (liftIO (putStrLn "Migrate"))
8381 & pqThen (migrateUp migrations)
84− & pqThen numMigrations
82+ & pqThen (liftIO (putStrLn "Rollback"))
8583 & pqThen (migrateDown migrations)
86− & pqThen numMigrations
8784:}
88−Row 2
89−Row 0
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.
90122-}
91123
92124{-# LANGUAGE
93125 DataKinds
126+ , DeriveGeneric
127+ , FlexibleContexts
128+ , FlexibleInstances
94129 , GADTs
95130 , LambdaCase
96− , PolyKinds
97131 , OverloadedLabels
132+ , OverloadedStrings
133+ , PolyKinds
134+ , QuantifiedConstraints
135+ , RankNTypes
98136 , TypeApplications
99− , FlexibleContexts
100137 , TypeOperators
101138#-}
102139
103140module Squeal.PostgreSQL.Migration
104141 ( -- * Migration
105142 Migration (..)
106− , migrateUp
107− , migrateDown
108− -- * Migration table
143+ , Migratory (..)
144+ , Terminally (..)
145+ , terminally
146+ , pureMigration
109147 , MigrationsTable
110− , createMigrations
111− , insertMigration
112− , deleteMigration
113− , selectMigration
148+ , defaultMain
114149 ) where
115150
151+import Control.Category
116152import Control.Monad
117−import Control.Monad.Base
118−import Control.Monad.Trans.Control
119−import Generics.SOP (K(..))
153+import Data.ByteString (ByteString)
154+import Data.Foldable (traverse_)
120155import Data.Function ((&))
156+import Data.List ((\\))
121157import Data.Text (Text)
158+import Data.Time (UTCTime)
159+import Prelude hiding ((.), id)
160+import System.Environment
161+import UnliftIO (MonadIO (..))
122162
123−import Squeal.PostgreSQL
163+import qualified Data.Text.IO as Text (putStrLn)
164+import qualified Generics.SOP as SOP
165+import qualified GHC.Generics as GHC
124166
125−-- | A `Migration` should contain an inverse pair of
126−-- `up` and `down` instructions and a unique `name`.
127−data Migration io schemas0 schemas1 = Migration
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
182+
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
128187 { name :: Text -- ^ The `name` of a `Migration`.
129188 -- Each `name` in a `Migration` should be unique.
130− , up :: PQ schemas0 schemas1 io () -- ^ The `up` instruction of a `Migration`.
131− , down :: PQ schemas1 schemas0 io () -- ^ The `down` instruction of a `Migration`.
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
132260 }
133261
134−-- | Run `Migration`s by creating the `MigrationsTable`
135−-- if it does not exist and then in a transaction, for each each `Migration`
136−-- query to see if the `Migration` is executed. If not, then
137−-- execute the `Migration` and insert its row in the `MigrationsTable`.
138−migrateUp
139− :: MonadBaseControl IO io
140− => AlignedList (Migration io) schemas0 schemas1 -- ^ migrations to run
141− -> PQ
142− ("migrations" ::: MigrationsSchema ': schemas0)
143− ("migrations" ::: MigrationsSchema ': schemas1)
144− io ()
145−migrateUp migration =
146− define createMigrations
147− & pqBind okResult
148− & pqThen (transactionallySchema_ (upMigrations migration))
149− where
262+instance Migratory (Terminally PQ IO) where
150263
151− upMigrations
152− :: MonadBaseControl IO io
153− => AlignedList (Migration io) schemas0 schemas1
154− -> PQ
155− ("migrations" ::: MigrationsSchema ': schemas0)
156− ("migrations" ::: MigrationsSchema ': schemas1)
157− io ()
158− upMigrations = \case
159− Done -> return ()
160− step :>> steps -> upMigration step & pqThen (upMigrations steps)
161−
162− upMigration
163− :: MonadBase IO io
164− => Migration io schemas0 schemas1 -> PQ
165− ("migrations" ::: MigrationsSchema ': schemas0)
166− ("migrations" ::: MigrationsSchema ': schemas1)
167− io ()
168− upMigration step =
169− queryExecuted step
170− & pqBind (\ executed ->
171− if executed == 1 -- up step has already been executed
172− then PQ (\ _ -> return (K ())) -- unsafely switch schemas
173− else
174− pqEmbed (up step) -- safely switch schemas
175− & pqThen (manipulateParams insertMigration (Only (name step)))
176− -- insert execution record
177− & pqBind okResult)
178−
179− queryExecuted
180− :: MonadBase IO io
181− => Migration io schemas0 schemas1 -> PQ
182− ("migrations" ::: MigrationsSchema ': schemas0)
183− ("migrations" ::: MigrationsSchema ': schemas0)
184− io Row
185− queryExecuted step = do
186− result <- runQueryParams selectMigration (Only (name step))
187− okResult result
188− ntuples result
189−
190−-- | Rewind `Migration`s by creating the `MigrationsTable`
191−-- if it does not exist and then in a transaction, for each each `Migration`
192−-- query to see if the `Migration` is executed. If it is, then
193−-- rewind the `Migration` and delete its row in the `MigrationsTable`.
194−migrateDown
195− :: MonadBaseControl IO io
196− => AlignedList (Migration io) schemas0 schemas1 -- ^ migrations to rewind
197− -> PQ
198− ("migrations" ::: MigrationsSchema ': schemas1)
199− ("migrations" ::: MigrationsSchema ': schemas0)
200− io ()
201−migrateDown migrations =
202− define createMigrations
203− & pqBind okResult
204− & pqThen (transactionallySchema_ (downMigrations migrations))
205− where
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
206292
207− downMigrations
208− :: MonadBaseControl IO io
209− => AlignedList (Migration io) schemas0 schemas1 -> PQ
210− ("migrations" ::: MigrationsSchema ': schemas1)
211− ("migrations" ::: MigrationsSchema ': schemas0)
212− io ()
213− downMigrations = \case
214− Done -> return ()
215− step :>> steps -> downMigrations steps & pqThen (downMigration step)
216−
217− downMigration
218− :: MonadBase IO io
219− => Migration io schemas0 schemas1 -> PQ
220− ("migrations" ::: MigrationsSchema ': schemas1)
221− ("migrations" ::: MigrationsSchema ': schemas0)
222− io ()
223− downMigration step =
224− queryExecuted step
225− & pqBind (\ executed ->
226− if executed == 0 -- up step has not been executed
227− then PQ (\ _ -> return (K ())) -- unsafely switch schemas
228− else
229− pqEmbed (down step) -- safely switch schemas
230− & pqThen (manipulateParams deleteMigration (Only (name step)))
231− -- delete execution record
232− & pqBind okResult)
233−
234− queryExecuted
235− :: MonadBase IO io
236− => Migration io schemas0 schemas1 -> PQ
237− ("migrations" ::: MigrationsSchema ': schemas1)
238− ("migrations" ::: MigrationsSchema ': schemas1)
239− io Row
240− queryExecuted step = do
241− result <- runQueryParams selectMigration (Only (name step))
242− okResult result
243− ntuples result
244−
245−okResult :: MonadBase IO io => K Result results -> PQ schema schema io ()
246−okResult result = do
247− status <- resultStatus result
248− when (not (status `elem` [CommandOk, TuplesOk])) $ do
249− errorMessageMaybe <- resultErrorMessage result
250− case errorMessageMaybe of
251− Nothing -> error "migrateDown: unknown error"
252− Just msg -> error ("migrationDown: " <> show msg)
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))
314+
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
321+
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
253324
254325-- | The `TableType` for a Squeal migration.
255326type MigrationsTable =
@@ -258,40 +329,120 @@ type MigrationsTable =
258329 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz
259330 ]
260331
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+
261340type MigrationsSchema = '["schema_migrations" ::: 'Table MigrationsTable]
341+type MigrationsSchemas = Public MigrationsSchema
262342
263343-- | Creates a `MigrationsTable` if it does not already exist.
264−createMigrations
265− :: Has "migrations" schemas MigrationsSchema
266− => Definition schemas schemas
344+createMigrations :: Definition MigrationsSchemas MigrationsSchemas
267345createMigrations =
268− createSchemaIfNotExists #migrations >>>
269− createTableIfNotExists (#migrations ! #schema_migrations)
346+ createTableIfNotExists #schema_migrations
270347 ( (text & notNullable) `as` #name :*
271348 (timestampWithTimeZone & notNullable & default_ currentTimestamp)
272349 `as` #executed_at )
273350 ( unique #name `as` #migrations_unique_name )
274351
275−-- | Inserts a `Migration` into the `MigrationsTable`
276−insertMigration
277− :: Has "migrations" schemas MigrationsSchema
278− => Manipulation '[] schemas '[ 'NotNull 'PGtext] '[]
279−insertMigration = insertInto_ (#migrations ! #schema_migrations) . Values_ $
280− (param @1) `as` #name :* defaultAs #executed_at
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))
281357
282−-- | Deletes a `Migration` from the `MigrationsTable`
283−deleteMigration
284− :: Has "migrations" schemas MigrationsSchema
285− => Manipulation '[] schemas '[ 'NotNull 'PGtext ] '[]
286−deleteMigration = deleteFrom_ (#migrations ! #schema_migrations) (#name .== param @1)
358+-- | Deletes a `Migration` from the `MigrationsTable`, returning
359+-- the time at which it was inserted.
360+deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()
361+deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)
287362
288363-- | Selects a `Migration` from the `MigrationsTable`, returning
289−-- the time at which it was executed.
364+-- the time at which it was inserted.
290365selectMigration
291− :: Has "migrations" schemas MigrationsSchema
292− => Query '[] '[] schemas '[ 'NotNull 'PGtext ]
293− '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]
294−selectMigration = select_
295− (#executed_at `as` #executed_at)
296− ( from (table ((#migrations ! #schema_migrations) `as` #m))
297− & where_ (#name .== param @1))
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
squeal-postgresql/src/Squeal/PostgreSQL/PG.hsnew file+388
@@ -0,0 +1,388 @@
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+138−103
@@ -24,6 +24,7 @@ of executing Squeal commands.
2424 , FunctionalDependencies
2525 , FlexibleContexts
2626 , FlexibleInstances
27+ , InstanceSigs
2728 , OverloadedStrings
2829 , RankNTypes
2930 , ScopedTypeVariables
@@ -48,8 +49,6 @@ module Squeal.PostgreSQL.PQ
4849 , evalPQ
4950 , IndexedMonadTransPQ (..)
5051 , MonadPQ (..)
51− , PQRun
52− , pqliftWith
5352 -- * Results
5453 , LibPQ.Result
5554 , LibPQ.Row
@@ -65,18 +64,21 @@ module Squeal.PostgreSQL.PQ
6564 , resultErrorCode
6665 -- * Exceptions
6766 , SquealException (..)
67+ , PQState (..)
68+ , okResult
6869 , catchSqueal
6970 , handleSqueal
71+ , trySqueal
7072 ) where
7173
72−import Control.Exception.Lifted
73−import Control.Monad.Base
74+import Control.Exception (Exception, throw)
7475import Control.Monad.Except
7576import Control.Monad.Morph
76−import Control.Monad.Trans.Control
77+import UnliftIO (MonadUnliftIO (..), bracket, catch, handle, try)
7778import Data.ByteString (ByteString)
7879import Data.Foldable
7980import Data.Function ((&))
81+import Data.Functor ((<&>))
8082import Data.Kind
8183import Data.Text (pack, Text)
8284import Data.Traversable
@@ -85,6 +87,7 @@ import PostgreSQL.Binary.Encoding (encodingBytes)
8587
8688import qualified Control.Monad.Fail as Fail
8789import qualified Database.PostgreSQL.LibPQ as LibPQ
90+import qualified PostgreSQL.Binary.Encoding as Encoding
8891
8992import Squeal.PostgreSQL.Binary
9093import Squeal.PostgreSQL.Definition
@@ -105,6 +108,9 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict
105108import qualified Control.Monad.Trans.RWS.Lazy as Lazy
106109import qualified Control.Monad.Trans.RWS.Strict as Strict
107110
111+-- $setup
112+-- >>> import Squeal.PostgreSQL
113+
108114{- | Makes a new connection to the database server.
109115
110116This function opens a new database connection using the parameters taken
@@ -132,19 +138,19 @@ with the wrong schema!
132138-}
133139connectdb
134140 :: forall schemas io
135− . MonadBase IO io
141+ . MonadIO io
136142 => ByteString -- ^ conninfo
137143 -> io (K LibPQ.Connection schemas)
138−connectdb = fmap K . liftBase . LibPQ.connectdb
144+connectdb = fmap K . liftIO . LibPQ.connectdb
139145
140146-- | Closes the connection to the server.
141−finish :: MonadBase IO io => K LibPQ.Connection schemas -> io ()
142−finish = liftBase . LibPQ.finish . unK
147+finish :: MonadIO io => K LibPQ.Connection schemas -> io ()
148+finish = liftIO . LibPQ.finish . unK
143149
144150-- | Do `connectdb` and `finish` before and after a computation.
145151withConnection
146152 :: forall schemas0 schemas1 io x
147− . MonadBaseControl IO io
153+ . MonadUnliftIO io
148154 => ByteString
149155 -> PQ schemas0 schemas1 io x
150156 -> io x
@@ -202,8 +208,7 @@ evalPQ (PQ pq) conn = unK <$> pq conn
202208-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).
203209-- An indexed monad transformer transforms a `Monad` into an indexed monad.
204210-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that
205−-- support running `Definition`s using `define` and embedding a computation
206−-- in a larger schema using `pqEmbed`.
211+-- support running `Definition`s using `define`.
207212class IndexedMonadTransPQ pq where
208213
209214 -- | indexed analog of `<*>`
@@ -243,19 +248,16 @@ class IndexedMonadTransPQ pq where
243248 -> x -> pq schemas0 schemas2 m z
244249 pqAndThen g f x = pqBind g (f x)
245250
246− -- | Safely embed a computation in a larger schema.
247− pqEmbed
248− :: Monad m
249− => pq schemas0 schemas1 m x
250− -> pq (schema ': schemas0) (schema : schemas1) m x
251−
252− -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law
251+ -- | Run a `Definition` with `LibPQ.exec`.
252+ --
253+ -- It should be functorial in effect.
253254 --
254− -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@
255+ -- @define id = return ()@
256+ -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@
255257 define
256− :: MonadBase IO io
258+ :: MonadIO io
257259 => Definition schemas0 schemas1
258− -> pq schemas0 schemas1 io (K LibPQ.Result '[])
260+ -> pq schemas0 schemas1 io ()
259261
260262instance IndexedMonadTransPQ PQ where
261263
@@ -268,16 +270,12 @@ instance IndexedMonadTransPQ PQ where
268270 K x' <- x conn
269271 unPQ (f x') (K (unK conn))
270272
271− pqEmbed (PQ pq) = PQ $ \ (K conn) -> do
272− K x <- pq (K conn)
273− return $ K x
274−
275273 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do
276− resultMaybe <- liftBase $ LibPQ.exec conn q
274+ resultMaybe <- liftIO $ LibPQ.exec conn q
277275 case resultMaybe of
278276 Nothing -> throw $ ResultException
279277 "define: LibPQ.exec returned no results"
280− Just result -> return $ K (K result)
278+ Just result -> K <$> okResult_ result
281279
282280{- | `MonadPQ` is an @mtl@ style constraint, similar to
283281`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to
@@ -286,8 +284,12 @@ instance IndexedMonadTransPQ PQ where
286284 with a `ToParams` constraint. It calls `LibPQ.execParams` and
287285 doesn't afraid of anything.
288286
287+* `manipulateParams_` is like `manipulateParams` for a returning-free statement.
288+
289289* `manipulate` is like `manipulateParams` for a parameter-free statement.
290290
291+* `manipulate_` is like `manipulate` for a returning-free statement.
292+
291293* `runQueryParams` is like `manipulateParams` for query statements.
292294
293295* `runQuery` is like `runQueryParams` for a parameter-free statement.
@@ -301,7 +303,7 @@ instance IndexedMonadTransPQ PQ where
301303* `forPrepared` is a flipped `traversePrepared`
302304
303305* `traversePrepared_` is like `traversePrepared` but works on `Foldable`
304− containers and returns unit.
306+ containers for a returning-free statement.
305307
306308* `forPrepared_` is a flipped `traversePrepared_`.
307309
@@ -315,24 +317,34 @@ a default instance.
315317-}
316318class Monad pq => MonadPQ schemas pq | pq -> schemas where
317319 manipulateParams
318− :: ToParams x params
320+ :: (ToParams x params, All OidOfParam params)
319321 => Manipulation '[] schemas params ys
320322 -- ^ `insertInto`, `update` or `deleteFrom`
321323 -> x -> pq (K LibPQ.Result ys)
322324 default manipulateParams
323325 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
324− => ToParams x params
326+ => (ToParams x params, All OidOfParam params)
325327 => Manipulation '[] schemas params ys
326328 -- ^ `insertInto`, `update` or `deleteFrom`
327329 -> x -> pq (K LibPQ.Result ys)
328330 manipulateParams manipulation params = lift $
329331 manipulateParams manipulation params
330332
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+
331340 manipulate :: Manipulation '[] schemas '[] ys -> pq (K LibPQ.Result ys)
332341 manipulate statement = manipulateParams statement ()
333342
343+ manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()
344+ manipulate_ = void . manipulate
345+
334346 runQueryParams
335− :: ToParams x params
347+ :: (ToParams x params, All OidOfParam params)
336348 => Query '[] '[] schemas params ys
337349 -- ^ `select` and friends
338350 -> x -> pq (K LibPQ.Result ys)
@@ -345,19 +357,19 @@ class Monad pq => MonadPQ schemas pq | pq -> schemas where
345357 runQuery q = runQueryParams q ()
346358
347359 traversePrepared
348− :: (ToParams x params, Traversable list)
360+ :: (ToParams x params, Traversable list, All OidOfParam params)
349361 => Manipulation '[] schemas params ys
350362 -- ^ `insertInto`, `update`, or `deleteFrom`, and friends
351363 -> list x -> pq (list (K LibPQ.Result ys))
352364 default traversePrepared
353365 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
354− => (ToParams x params, Traversable list)
366+ => (ToParams x params, Traversable list, All OidOfParam params)
355367 => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))
356368 traversePrepared manipulation params = lift $
357369 traversePrepared manipulation params
358370
359371 forPrepared
360− :: (ToParams x params, Traversable list)
372+ :: (ToParams x params, Traversable list, All OidOfParam params)
361373 => list x
362374 -> Manipulation '[] schemas params ys
363375 -- ^ `insertInto`, `update` or `deleteFrom`
@@ -365,13 +377,13 @@ class Monad pq => MonadPQ schemas pq | pq -> schemas where
365377 forPrepared = flip traversePrepared
366378
367379 traversePrepared_
368− :: (ToParams x params, Foldable list)
380+ :: (ToParams x params, Foldable list, All OidOfParam params)
369381 => Manipulation '[] schemas params '[]
370382 -- ^ `insertInto`, `update` or `deleteFrom`
371383 -> list x -> pq ()
372384 default traversePrepared_
373385 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)
374− => (ToParams x params, Foldable list)
386+ => (ToParams x params, Foldable list, All OidOfParam params)
375387 => Manipulation '[] schemas params '[]
376388 -- ^ `insertInto`, `update` or `deleteFrom`
377389 -> list x -> pq ()
@@ -379,7 +391,7 @@ class Monad pq => MonadPQ schemas pq | pq -> schemas where
379391 traversePrepared_ manipulation params
380392
381393 forPrepared_
382− :: (ToParams x params, Foldable list)
394+ :: (ToParams x params, Foldable list, All OidOfParam params)
383395 => list x
384396 -> Manipulation '[] schemas params '[]
385397 -- ^ `insertInto`, `update` or `deleteFrom`
@@ -392,61 +404,83 @@ class Monad pq => MonadPQ schemas pq | pq -> schemas where
392404 => (LibPQ.Connection -> IO a) -> pq a
393405 liftPQ = lift . liftPQ
394406
395−instance (MonadBase IO io, schemas0 ~ schemas, schemas1 ~ schemas)
407+instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)
396408 => MonadPQ schemas (PQ schemas0 schemas1 io) where
397409
398410 manipulateParams
399411 (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =
400412 PQ $ \ (K conn) -> do
401413 let
402− toParam' encoding =
403− (LibPQ.invalidOid, encodingBytes encoding, LibPQ.Binary)
404− params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))
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
405425 q' = q <> ";"
406− resultMaybe <- liftBase $ LibPQ.execParams conn q' params' LibPQ.Binary
426+ resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary
407427 case resultMaybe of
408428 Nothing -> throw $ ResultException
409429 "manipulateParams: LibPQ.execParams returned no results"
410430 Just result -> do
411− tryResult result
431+ okResult_ result
412432 return $ K (K result)
413433
414434 traversePrepared
415435 (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =
416− PQ $ \ (K conn) -> liftBase $ do
417− let temp = "temporary_statement"
418− prepResultMaybe <- LibPQ.prepare conn temp q Nothing
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')
419446 case prepResultMaybe of
420447 Nothing -> throw $ ResultException
421448 "traversePrepared: LibPQ.prepare returned no results"
422− Just prepResult -> tryResult prepResult
449+ Just prepResult -> okResult_ prepResult
423450 results <- for list $ \ params -> do
424451 let
425− toParam' encoding = (encodingBytes encoding,LibPQ.Binary)
452+ toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
426453 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))
427454 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary
428455 case resultMaybe of
429456 Nothing -> throw $ ResultException
430457 "traversePrepared: LibPQ.execParams returned no results"
431458 Just result -> do
432− tryResult result
459+ okResult_ result
433460 return $ K result
434461 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
435462 case deallocResultMaybe of
436463 Nothing -> throw $ ResultException
437464 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
438− Just deallocResult -> tryResult deallocResult
465+ Just deallocResult -> okResult_ deallocResult
439466 return (K results)
440467
441468 traversePrepared_
442469 (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =
443− PQ $ \ (K conn) -> liftBase $ do
444− let temp = "temporary_statement"
445− prepResultMaybe <- LibPQ.prepare conn temp q Nothing
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')
446480 case prepResultMaybe of
447481 Nothing -> throw $ ResultException
448482 "traversePrepared_: LibPQ.prepare returned no results"
449− Just prepResult -> tryResult prepResult
483+ Just prepResult -> okResult_ prepResult
450484 for_ list $ \ params -> do
451485 let
452486 toParam' encoding = (encodingBytes encoding, LibPQ.Binary)
@@ -455,16 +489,16 @@ instance (MonadBase IO io, schemas0 ~ schemas, schemas1 ~ schemas)
455489 case resultMaybe of
456490 Nothing -> throw $ ResultException
457491 "traversePrepared_: LibPQ.execParams returned no results"
458− Just result -> tryResult result
492+ Just result -> okResult_ result
459493 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")
460494 case deallocResultMaybe of
461495 Nothing -> throw $ ResultException
462496 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"
463− Just deallocResult -> tryResult deallocResult
497+ Just deallocResult -> okResult_ deallocResult
464498 return (K ())
465499
466500 liftPQ pq = PQ $ \ (K conn) -> do
467− y <- liftBase $ pq conn
501+ y <- liftIO $ pq conn
468502 return (K y)
469503
470504instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)
@@ -505,40 +539,29 @@ instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where
505539 embed f (PQ pq) = PQ $ \ conn -> do
506540 evalPQ (f (pq conn)) conn
507541
508−instance (MonadBase b m, schemas0 ~ schemas1)
509− => MonadBase b (PQ schemas0 schemas1 m) where
510− liftBase = lift . liftBase
511−
512542instance (MonadIO m, schema0 ~ schema1)
513543 => MonadIO (PQ schema0 schema1 m) where
514544 liftIO = lift . liftIO
515545
516−-- | A snapshot of the state of a `PQ` computation.
517−type PQRun schemas =
518− forall m x. Monad m => PQ schemas schemas m x -> m (K x schemas)
519−
520−-- | Helper function in defining `MonadBaseControl` instance for `PQ`.
521−pqliftWith :: Functor m => (PQRun schemas -> m a) -> PQ schemas schemas m a
522−pqliftWith f = PQ $ \ conn ->
523− fmap K (f $ \ pq -> unPQ pq conn)
524−
525−instance (MonadBaseControl b m, schemas0 ~ schemas1)
526− => MonadBaseControl b (PQ schemas0 schemas1 m) where
527− type StM (PQ schemas0 schemas1 m) x = StM m (K x schemas0)
528− liftBaseWith f =
529− pqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run
530− restoreM = PQ . const . restoreM
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)
531554
532555-- | Get a row corresponding to a given row number from a `LibPQ.Result`,
533556-- throwing an exception if the row number is out of bounds.
534557getRow
535− :: (FromRow columns y, MonadBase IO io)
558+ :: (FromRow columns y, MonadIO io)
536559 => LibPQ.Row
537560 -- ^ row number
538561 -> K LibPQ.Result columns
539562 -- ^ result
540563 -> io y
541−getRow r (K result :: K LibPQ.Result columns) = liftBase $ do
564+getRow r (K result :: K LibPQ.Result columns) = liftIO $ do
542565 numRows <- LibPQ.ntuples result
543566 when (numRows < r) $ throw $ ResultException $
544567 "getRow: expected at least " <> pack (show r) <> "rows but only saw "
@@ -556,13 +579,13 @@ getRow r (K result :: K LibPQ.Result columns) = liftBase $ do
556579-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,
557580-- otherwise returning the row along with the next row number.
558581nextRow
559− :: (FromRow columns y, MonadBase IO io)
582+ :: (FromRow columns y, MonadIO io)
560583 => LibPQ.Row -- ^ total number of rows
561584 -> K LibPQ.Result columns -- ^ result
562585 -> LibPQ.Row -- ^ row number
563586 -> io (Maybe (LibPQ.Row,y))
564587nextRow total (K result :: K LibPQ.Result columns) r
565− = liftBase $ if r >= total then return Nothing else do
588+ = liftIO $ if r >= total then return Nothing else do
566589 let len = fromIntegral (lengthSList (Proxy @columns))
567590 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]
568591 case fromList row' of
@@ -573,10 +596,10 @@ nextRow total (K result :: K LibPQ.Result columns) r
573596
574597-- | Get all rows from a `LibPQ.Result`.
575598getRows
576− :: (FromRow columns y, MonadBase IO io)
599+ :: (FromRow columns y, MonadIO io)
577600 => K LibPQ.Result columns -- ^ result
578601 -> io [y]
579−getRows (K result :: K LibPQ.Result columns) = liftBase $ do
602+getRows (K result :: K LibPQ.Result columns) = liftIO $ do
580603 let len = fromIntegral (lengthSList (Proxy @columns))
581604 numRows <- LibPQ.ntuples result
582605 for [0 .. numRows - 1] $ \ r -> do
@@ -589,10 +612,10 @@ getRows (K result :: K LibPQ.Result columns) = liftBase $ do
589612
590613-- | Get the first row if possible from a `LibPQ.Result`.
591614firstRow
592− :: (FromRow columns y, MonadBase IO io)
615+ :: (FromRow columns y, MonadIO io)
593616 => K LibPQ.Result columns -- ^ result
594617 -> io (Maybe y)
595−firstRow (K result :: K LibPQ.Result columns) = liftBase $ do
618+firstRow (K result :: K LibPQ.Result columns) = liftIO $ do
596619 numRows <- LibPQ.ntuples result
597620 if numRows <= 0 then return Nothing else do
598621 let len = fromIntegral (lengthSList (Proxy @columns))
@@ -605,23 +628,23 @@ firstRow (K result :: K LibPQ.Result columns) = liftBase $ do
605628
606629-- | Lifts actions on results from @LibPQ@.
607630liftResult
608− :: MonadBase IO io
631+ :: MonadIO io
609632 => (LibPQ.Result -> IO x)
610633 -> K LibPQ.Result results -> io x
611−liftResult f (K result) = liftBase $ f result
634+liftResult f (K result) = liftIO $ f result
612635
613636-- | Returns the number of rows (tuples) in the query result.
614−ntuples :: MonadBase IO io => K LibPQ.Result columns -> io LibPQ.Row
637+ntuples :: MonadIO io => K LibPQ.Result columns -> io LibPQ.Row
615638ntuples = liftResult LibPQ.ntuples
616639
617640-- | Returns the result status of the command.
618−resultStatus :: MonadBase IO io => K LibPQ.Result results -> io LibPQ.ExecStatus
641+resultStatus :: MonadIO io => K LibPQ.Result results -> io LibPQ.ExecStatus
619642resultStatus = liftResult LibPQ.resultStatus
620643
621644-- | Returns the error message most recently generated by an operation
622645-- on the connection.
623646resultErrorMessage
624− :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)
647+ :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)
625648resultErrorMessage = liftResult LibPQ.resultErrorMessage
626649
627650-- | Returns the error code most recently generated by an operation
@@ -629,29 +652,29 @@ resultErrorMessage = liftResult LibPQ.resultErrorMessage
629652--
630653-- https://www.postgresql.org/docs/current/static/errcodes-appendix.html
631654resultErrorCode
632− :: MonadBase IO io
655+ :: MonadIO io
633656 => K LibPQ.Result results
634657 -> io (Maybe ByteString)
635658resultErrorCode = liftResult (flip LibPQ.resultErrorField LibPQ.DiagSqlstate)
636659
637−-- | `Exception`s that can be thrown by Squeal.
638−data SquealException
639− = PQException
660+-- | the state of LibPQ
661+data PQState = PQState
640662 { sqlExecStatus :: LibPQ.ExecStatus
641663 , sqlStateCode :: Maybe ByteString
642664 -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html
643665 , sqlErrorMessage :: Maybe ByteString
644− }
666+ } deriving (Eq, Show)
667+
668+-- | `Exception`s that can be thrown by Squeal.
669+data SquealException
670+ = PQException PQState
645671 | ResultException Text
646672 | ParseException Text
647673 deriving (Eq, Show)
648674instance Exception SquealException
649675
650−tryResult
651− :: MonadBase IO io
652− => LibPQ.Result
653− -> io ()
654−tryResult result = liftBase $ do
676+okResult_ :: MonadIO io => LibPQ.Result -> io ()
677+okResult_ result = liftIO $ do
655678 status <- LibPQ.resultStatus result
656679 case status of
657680 LibPQ.CommandOk -> return ()
@@ -659,11 +682,16 @@ tryResult result = liftBase $ do
659682 _ -> do
660683 stateCode <- LibPQ.resultErrorField result LibPQ.DiagSqlstate
661684 msg <- LibPQ.resultErrorMessage result
662− throw $ PQException status stateCode msg
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
663691
664692-- | Catch `SquealException`s.
665693catchSqueal
666− :: MonadBaseControl IO io
694+ :: MonadUnliftIO io
667695 => io a
668696 -> (SquealException -> io a) -- ^ handler
669697 -> io a
@@ -671,7 +699,14 @@ catchSqueal = catch
671699
672700-- | Handle `SquealException`s.
673701handleSqueal
674− :: MonadBaseControl IO io
702+ :: MonadUnliftIO io
675703 => (SquealException -> io a) -- ^ handler
676704 -> io a -> io a
677705handleSqueal = 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+72−109
@@ -1,17 +1,40 @@
11{-|
2−Module: Squeal.PostgreSQL.Definition
3−Description: Pooled connections
2+Module: Squeal.PostgreSQL.Pool
3+Description: Connection pools
44Copyright: (c) Eitan Chatav, 2017
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
8−A `MonadPQ` for pooled connections.
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
931-}
1032
1133{-# LANGUAGE
1234 DeriveFunctor
1335 , FlexibleContexts
1436 , FlexibleInstances
37+ , InstanceSigs
1538 , MultiParamTypeClasses
1639 , RankNTypes
1740 , ScopedTypeVariables
@@ -22,57 +45,24 @@ A `MonadPQ` for pooled connections.
2245
2346module Squeal.PostgreSQL.Pool
2447 ( -- * Pools
25− PoolPQ (..)
48+ Pool
2649 , createConnectionPool
27− , Pool
28− , destroyAllResources
29− , PoolPQRun
30− , poolpqliftWith
50+ , usingConnectionPool
51+ , destroyConnectionPool
3152 ) where
3253
33−import Control.Monad.Base
34−import Control.Monad.Trans
35−import Control.Monad.Trans.Control
3654import Data.ByteString
37−import Data.Pool
3855import Data.Time
39−import Generics.SOP (K(..))
40−
41−import qualified Control.Monad.Fail as Fail
56+import Generics.SOP (K(..), unK)
57+import UnliftIO (MonadUnliftIO (..))
58+import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)
4259
4360import Squeal.PostgreSQL.PQ
44−import Squeal.PostgreSQL.Schema
45−
46−{- | `PoolPQ` @schemas@ should be a drop-in replacement for `PQ` @schemas schemas@.
47−
48−Typical use case would be to create your pool using `createConnectionPool` and run anything that requires the pool connection with it.
49−
50−Here's a simplified example:
51−
52−> type Schema = '[ "tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint2])]
53−>
54−> someQuery :: Manipulation Schema '[ 'NotNull 'PGint2] '[]
55−> someQuery = insertRow #tab
56−> (Set (param @1) `As` #col :* Nil)
57−> OnConflictDoNothing (Returning Nil)
58−>
59−> insertOne :: (MonadBaseControl IO m, MonadPQ Schema m) => m ()
60−> insertOne = void $ manipulateParams someQuery . Only $ (1 :: Int16)
61−>
62−> insertOneInPool :: ByteString -> IO ()
63−> insertOneInPool connectionString = do
64−> pool <- createConnectionPool connectionString 1 0.5 10
65−> liftIO $ runPoolPQ (insertOne) pool
66−
67−-}
68−newtype PoolPQ (schemas :: SchemasType) m x =
69− PoolPQ { runPoolPQ :: Pool (K Connection schemas) -> m x }
70− deriving Functor
7161
7262-- | Create a striped pool of connections.
7363-- 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.
7464createConnectionPool
75− :: MonadBase IO io
65+ :: MonadUnliftIO io
7666 => ByteString
7767 -- ^ The passed string can be empty to use all default parameters, or it can
7868 -- contain one or more parameter settings separated by whitespace.
@@ -89,71 +79,44 @@ createConnectionPool
8979 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.
9080 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.
9181 -> io (Pool (K Connection schemas))
92−createConnectionPool conninfo stripes idle maxResrc = liftBase $
82+createConnectionPool conninfo stripes idle maxResrc =
9383 createPool (connectdb conninfo) finish stripes idle maxResrc
9484
95−-- | `Applicative` instance for `PoolPQ`.
96−instance Monad m => Applicative (PoolPQ schemas m) where
97− pure x = PoolPQ $ \ _ -> pure x
98− PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do
99− f' <- f pool
100− x' <- x pool
101− return $ f' x'
102−
103−-- | `Monad` instance for `PoolPQ`.
104−instance Monad m => Monad (PoolPQ schemas m) where
105− return = pure
106− PoolPQ x >>= f = PoolPQ $ \ pool -> do
107− x' <- x pool
108− runPoolPQ (f x') pool
109−
110−-- | `Fail.MonadFail` instance for `PoolPQ`.
111−instance Monad m => Fail.MonadFail (PoolPQ schemas m) where
112− fail = Fail.fail
113−
114−-- | `MonadTrans` instance for `PoolPQ`.
115−instance MonadTrans (PoolPQ schemas) where
116− lift m = PoolPQ $ \ _pool -> m
117−
118−-- | `MonadBase` instance for `PoolPQ`.
119−instance MonadBase b m => MonadBase b (PoolPQ schemas m) where
120− liftBase = lift . liftBase
121−
122−-- | `MonadPQ` instance for `PoolPQ`.
123−instance MonadBaseControl IO io => MonadPQ schemas (PoolPQ schemas io) where
124− manipulateParams manipulation params = PoolPQ $ \ pool -> do
125− withResource pool $ \ conn -> do
126− (K result :: K (K Result ys) schemas) <- flip unPQ conn $
127− manipulateParams manipulation params
128− return result
129− traversePrepared manipulation params = PoolPQ $ \ pool ->
130− withResource pool $ \ conn -> do
131− (K result :: K (list (K Result ys)) schemas) <- flip unPQ conn $
132− traversePrepared manipulation params
133− return result
134− traversePrepared_ manipulation params = PoolPQ $ \ pool -> do
135− withResource pool $ \ conn -> do
136− (_ :: K () schemas) <- flip unPQ conn $
137− traversePrepared_ manipulation params
138− return ()
139− liftPQ m = PoolPQ $ \ pool ->
140− withResource pool $ \ conn -> do
141− (K result :: K result schemas) <- flip unPQ conn $
142− liftPQ m
143− return result
144−
145−-- | A snapshot of the state of a `PoolPQ` computation.
146−type PoolPQRun schemas =
147− forall m x. Monad m => PoolPQ schemas m x -> m x
148−
149−-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.
150−poolpqliftWith :: Functor m => (PoolPQRun schemas -> m a) -> PoolPQ schemas m a
151−poolpqliftWith f = PoolPQ $ \ pool ->
152− (f $ \ pq -> runPoolPQ pq pool)
153−
154−-- | `MonadBaseControl` instance for `PoolPQ`.
155−instance MonadBaseControl b m => MonadBaseControl b (PoolPQ schemas m) where
156− type StM (PoolPQ schemas m) x = StM m x
157− liftBaseWith f =
158− poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run
159− restoreM = PoolPQ . const . restoreM
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
squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+311−414
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL.Query
33Description: Squeal queries
4−Copyright: (c) Eitan Chatav, 2017
4+Copyright: (c) Eitan Chatav, 2019
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -17,6 +17,7 @@ Squeal queries.
1717 , GeneralizedNewtypeDeriving
1818 , LambdaCase
1919 , MultiParamTypeClasses
20+ , OverloadedLabels
2021 , OverloadedStrings
2122 , QuantifiedConstraints
2223 , ScopedTypeVariables
@@ -31,13 +32,15 @@ Squeal queries.
3132
3233module Squeal.PostgreSQL.Query
3334 ( -- * Queries
34− Query (..)
35− , Query_
35+ Query_
36+ , Query (..)
3637 -- ** Select
3738 , select
3839 , select_
3940 , selectDistinct
4041 , selectDistinct_
42+ , selectDistinctOn
43+ , selectDistinctOn_
4144 , Selection (..)
4245 -- ** Values
4346 , values
@@ -52,23 +55,7 @@ module Squeal.PostgreSQL.Query
5255 -- ** With
5356 , With (..)
5457 , CommonTableExpression (..)
55− -- ** Unnest
56− , unnest
57− -- ** Json
58− , jsonEach
59− , jsonbEach
60− , jsonEachAsText
61− , jsonbEachAsText
62− , jsonObjectKeys
63− , jsonbObjectKeys
64− , jsonPopulateRecord
65− , jsonbPopulateRecord
66− , jsonPopulateRecordSet
67− , jsonbPopulateRecordSet
68− , jsonToRecord
69− , jsonbToRecord
70− , jsonToRecordSet
71− , jsonbToRecordSet
58+ , withRecursive
7259 -- * Table Expressions
7360 , TableExpression (..)
7461 , from
@@ -92,13 +79,6 @@ module Squeal.PostgreSQL.Query
9279 , By (..)
9380 , GroupByClause (..)
9481 , HavingClause (..)
95− -- * Subquery Expressions
96− , exists
97− , in_
98− , notIn
99− , Operator
100− , subAll
101− , subAny
10282 ) where
10383
10484import Control.DeepSeq
@@ -111,14 +91,67 @@ import GHC.TypeLits
11191
11292import qualified GHC.Generics as GHC
11393
114−import Squeal.PostgreSQL.Binary
94+import Squeal.PostgreSQL.Alias
11595import 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
116101import Squeal.PostgreSQL.Render
117102import Squeal.PostgreSQL.Schema
118103
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+
119133{- |
120−The process of retrieving or the command to retrieve data from a database
121−is called a `Query`. Let's see some examples of queries.
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+:}
122155
123156simple query:
124157
@@ -126,7 +159,7 @@ simple query:
126159>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
127160>>> :{
128161let
129− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
162+ query :: Query_ (Public Schema) () (Row Int32 Int32)
130163 query = select Star (from (table #tab))
131164in printSQL query
132165:}
@@ -136,21 +169,21 @@ restricted query:
136169
137170>>> :{
138171let
139− query :: Query '[] '[] (Public Schema) '[] '["sum" ::: 'NotNull 'PGint4, "col1" ::: 'NotNull 'PGint4]
172+ query :: Query_ (Public Schema) () (Row Int32 Int32)
140173 query =
141− select_ ((#col1 + #col2) `as` #sum :* #col1)
174+ select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)
142175 ( from (table #tab)
143176 & where_ (#col1 .> #col2)
144177 & where_ (#col2 .> 0) )
145178in printSQL query
146179:}
147−SELECT ("col1" + "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
180+SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))
148181
149182subquery:
150183
151184>>> :{
152185let
153− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
186+ query :: Query_ (Public Schema) () (Row Int32 Int32)
154187 query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))
155188in printSQL query
156189:}
@@ -160,7 +193,7 @@ limits and offsets:
160193
161194>>> :{
162195let
163− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
196+ query :: Query_ (Public Schema) () (Row Int32 Int32)
164197 query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)
165198in printSQL query
166199:}
@@ -170,7 +203,7 @@ parameterized query:
170203
171204>>> :{
172205let
173− query :: Query '[] '[] (Public Schema) '[ 'NotNull 'PGint4] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
206+ query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)
174207 query = select Star (from (table #tab) & where_ (#col1 .> param @1))
175208in printSQL query
176209:}
@@ -180,21 +213,21 @@ aggregation query:
180213
181214>>> :{
182215let
183− query :: Query '[] '[] (Public Schema) '[] '["sum" ::: 'NotNull 'PGint4, "col1" ::: 'NotNull 'PGint4 ]
216+ query :: Query_ (Public Schema) () (Row Int64 Int32)
184217 query =
185− select_ (sum_ (All #col2) `as` #sum :* #col1)
218+ select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)
186219 ( from (table (#tab `as` #table1))
187220 & groupBy #col1
188− & having (#col1 + sum_ (Distinct #col2) .> 1) )
221+ & having (sum_ (Distinct #col2) .> 1) )
189222in printSQL query
190223:}
191−SELECT sum(ALL "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + sum(DISTINCT "col2")) > 1)
224+SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (sum(DISTINCT "col2") > 1)
192225
193226sorted query:
194227
195228>>> :{
196229let
197− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
230+ query :: Query_ (Public Schema) () (Row Int32 Int32)
198231 query = select Star (from (table #tab) & orderBy [#col1 & Asc])
199232in printSQL query
200233:}
@@ -202,14 +235,12 @@ SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC
202235
203236joins:
204237
205−>>> :set -XFlexibleContexts
206238>>> :{
207239type OrdersColumns =
208240 '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4
209− , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4
210− , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4
211− , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4
212− ]
241+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4
242+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4
243+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4 ]
213244:}
214245
215246>>> :{
@@ -225,22 +256,27 @@ type OrdersConstraints =
225256>>> :{
226257type OrdersSchema =
227258 '[ "orders" ::: 'Table (OrdersConstraints :=> OrdersColumns)
228− , "customers" ::: 'Table (CustomersConstraints :=> NamesColumns)
229− , "shippers" ::: 'Table (ShippersConstraints :=> NamesColumns) ]
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
230271:}
231272
232273>>> :{
233274let
234− query :: Query '[] '[] (Public OrdersSchema)
235− '[]
236− '[ "order_price" ::: 'NotNull 'PGfloat4
237− , "customer_name" ::: 'NotNull 'PGtext
238− , "shipper_name" ::: 'NotNull 'PGtext
239− ]
275+ query :: Query_ (Public OrdersSchema) () Order
240276 query = select_
241− ( #o ! #price `as` #order_price :*
242− #c ! #name `as` #customer_name :*
243− #s ! #name `as` #shipper_name )
277+ ( #o ! #price `as` #price :*
278+ #c ! #name `as` #customerName :*
279+ #s ! #name `as` #shipperName )
244280 ( from (table (#orders `as` #o)
245281 & innerJoin (table (#customers `as` #c))
246282 (#o ! #customer_id .== #c ! #id)
@@ -248,14 +284,16 @@ let
248284 (#o ! #shipper_id .== #s ! #id)) )
249285in printSQL query
250286:}
251−SELECT "o"."price" AS "order_price", "c"."name" AS "customer_name", "s"."name" AS "shipper_name" FROM "orders" AS "o" INNER JOIN "customers" AS "c" ON ("o"."customer_id" = "c"."id") INNER JOIN "shippers" AS "s" ON ("o"."shipper_id" = "s"."id")
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")
252288
253289self-join:
254290
255291>>> :{
256292let
257− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
258− query = select (#t1 & DotStar) (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))
293+ query :: Query_ (Public Schema) () (Row Int32 Int32)
294+ query = select
295+ (#t1 & DotStar)
296+ (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))
259297in printSQL query
260298:}
261299SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"
@@ -264,17 +302,19 @@ value queries:
264302
265303>>> :{
266304let
267− query :: Query '[] commons schemas '[] '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]
268− query = values (1 `as` #foo :* true `as` #bar) [2 `as` #foo :* false `as` #bar]
305+ query :: Query_ schemas () (Row String Bool)
306+ query = values
307+ ("true" `as` #col1 :* true `as` #col2)
308+ ["false" `as` #col1 :* false `as` #col2]
269309in printSQL query
270310:}
271−SELECT * FROM (VALUES (1, TRUE), (2, FALSE)) AS t ("foo", "bar")
311+SELECT * FROM (VALUES (E'true', TRUE), (E'false', FALSE)) AS t ("col1", "col2")
272312
273313set operations:
274314
275315>>> :{
276316let
277− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
317+ query :: Query_ (Public Schema) () (Row Int32 Int32)
278318 query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))
279319in printSQL query
280320:}
@@ -284,7 +324,7 @@ with queries:
284324
285325>>> :{
286326let
287− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
327+ query :: Query_ (Public Schema) () (Row Int32 Int32)
288328 query = with (
289329 select Star (from (table #tab)) `as` #cte1 :>>
290330 select Star (from (common #cte1)) `as` #cte2
@@ -297,40 +337,35 @@ window function queries
297337
298338>>> :{
299339let
300− query :: Query '[] '[] (Public Schema) '[] ["col1" ::: 'NotNull 'PGint4, "rank" ::: 'NotNull 'PGint8]
340+ query :: Query_ (Public Schema) () (Row Int32 Int64)
301341 query = select
302− (#col1 & Also (rank `as` #rank `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))
342+ (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))
303343 (from (table #tab))
304344in printSQL query
305345:}
306−SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "rank" FROM "tab" AS "tab"
346+SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "col2" FROM "tab" AS "tab"
307347
308348correlated subqueries
309349
310350>>> :{
311351let
312− query :: Query '[] '[] (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4]
352+ query :: Query_ (Public Schema) () (Only Int32)
313353 query =
314− select #col1 (from (table (#tab `as` #t1))
354+ select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))
315355 & where_ (exists (
316356 select Star (from (table (#tab `as` #t2))
317357 & where_ (#t2 ! #col2 .== #t1 ! #col1)))))
318358in printSQL query
319359:}
320−SELECT "col1" AS "col1" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))
360+SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))
361+
321362-}
322−newtype Query
323− (outer :: FromType)
324− (commons :: FromType)
363+type family Query_
325364 (schemas :: SchemasType)
326− (params :: [NullityType])
327− (row :: RowType)
328− = UnsafeQuery { renderQuery :: ByteString }
329− deriving (GHC.Generic,Show,Eq,Ord,NFData)
330−instance RenderSQL (Query outer commons schemas params row) where renderSQL = renderQuery
331−
332−type family Query_ (schemas :: SchemasType) (params :: Type) (row :: Type) where
333− Query_ schemas params row = Query '[] '[] schemas (TuplePG params) (RowPG row)
365+ (parameters :: Type)
366+ (row :: Type) where
367+ Query_ schemas params row =
368+ Query '[] '[] schemas (TuplePG params) (RowPG row)
334369
335370-- | The results of two queries can be combined using the set operation
336371-- `union`. Duplicate rows are eliminated.
@@ -402,35 +437,48 @@ q1 `exceptAll` q2 = UnsafeQuery $
402437SELECT queries
403438-----------------------------------------}
404439
405−data Selection outer grp commons schemas params from row where
406− List
407− :: SListI row
408− => NP (Aliased (Expression outer grp commons schemas params from)) row
409− -> Selection outer grp commons schemas params from row
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
410447 Star
411448 :: HasUnique tab from row
412− => Selection outer 'Ungrouped commons schemas params from row
449+ => Selection outer commons 'Ungrouped schemas params from row
450+ -- ^ `HasUnique` table in the `FromClause`
413451 DotStar
414452 :: Has tab from row
415453 => Alias tab
416− -> Selection outer 'Ungrouped commons schemas params from row
417− Also
418− :: Selection outer grp commons schemas params from right
419− -> Selection outer grp commons schemas params from left
420− -> Selection outer grp commons schemas params from (Join left right)
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
421461 Over
422462 :: SListI row
423− => NP (Aliased (WindowFunction outer grp commons schemas params from)) row
424− -> WindowDefinition outer grp commons schemas params from
425− -> Selection outer grp commons schemas params from 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
426474instance (KnownSymbol col, row ~ '[col ::: ty])
427475 => Aliasable col
428− (Expression outer grp commons schemas params from ty)
429− (Selection outer grp commons schemas params from row) where
476+ (Expression outer commons grp schemas params from ty)
477+ (Selection outer commons grp schemas params from row) where
430478 expr `as` col = List (expr `as` col)
431479instance (Has tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])
432480 => IsQualified tab col
433− (Selection outer 'Ungrouped commons schemas params from row1) where
481+ (Selection outer commons 'Ungrouped schemas params from row1) where
434482 tab ! col = tab ! col `as` col
435483instance
436484 ( Has tab (Join outer from) row0
@@ -438,11 +486,11 @@ instance
438486 , row1 ~ '[col ::: ty]
439487 , GroupedBy tab col bys )
440488 => IsQualified tab col
441− (Selection outer ('Grouped bys) commons schemas params from row1) where
489+ (Selection outer commons ('Grouped bys) schemas params from row1) where
442490 tab ! col = tab ! col `as` col
443491instance (HasUnique tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])
444492 => IsLabel col
445− (Selection outer 'Ungrouped commons schemas params from row1) where
493+ (Selection outer commons 'Ungrouped schemas params from row1) where
446494 fromLabel = fromLabel @col `as` Alias
447495instance
448496 ( HasUnique tab (Join outer from) row0
@@ -450,10 +498,10 @@ instance
450498 , row1 ~ '[col ::: ty]
451499 , GroupedBy tab col bys )
452500 => IsLabel col
453− (Selection outer ('Grouped bys) commons schemas params from row1) where
501+ (Selection outer commons ('Grouped bys) schemas params from row1) where
454502 fromLabel = fromLabel @col `as` Alias
455503
456−instance RenderSQL (Selection outer grp commons schemas params from row) where
504+instance RenderSQL (Selection outer commons grp schemas params from row) where
457505 renderSQL = \case
458506 List list -> renderCommaSeparated (renderAliased renderSQL) list
459507 Star -> "*"
@@ -462,7 +510,7 @@ instance RenderSQL (Selection outer grp commons schemas params from row) where
462510 Over winFns winDef ->
463511 let
464512 renderOver
465− :: Aliased (WindowFunction outer grp commons schemas params from) field
513+ :: Aliased (WindowFunction outer commons grp schemas params from) field
466514 -> ByteString
467515 renderOver (winFn `As` col) = renderSQL winFn
468516 <+> "OVER" <+> parenthesized (renderSQL winDef)
@@ -471,7 +519,7 @@ instance RenderSQL (Selection outer grp commons schemas params from row) where
471519 renderCommaSeparated renderOver winFns
472520
473521instance IsString
474− (Selection outer grp commons schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where
522+ (Selection outer commons grp schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where
475523 fromString str = fromString str `as` Alias
476524
477525-- | the `TableExpression` in the `select` command constructs an intermediate
@@ -481,9 +529,9 @@ instance IsString
481529-- the intermediate table are actually output.
482530select
483531 :: (SListI row, row ~ (x ': xs))
484− => Selection outer grp commons schemas params from row
485− -- ^ select list
486− -> TableExpression outer grp commons schemas params from
532+ => Selection outer commons grp schemas params from row
533+ -- ^ selection
534+ -> TableExpression outer commons grp schemas params from
487535 -- ^ intermediate virtual table
488536 -> Query outer commons schemas params row
489537select selection tabexpr = UnsafeQuery $
@@ -491,20 +539,24 @@ select selection tabexpr = UnsafeQuery $
491539 <+> renderSQL selection
492540 <+> renderSQL tabexpr
493541
542+-- | Like `select` but takes an `NP` list of `Expression`s instead
543+-- of a general `Selection`.
494544select_
495545 :: (SListI row, row ~ (x ': xs))
496− => NP (Aliased (Expression outer grp commons schemas params from)) row
497− -> TableExpression outer grp commons schemas params from
546+ => NP (Aliased (Expression outer commons grp schemas params from)) row
547+ -- ^ select list
548+ -> TableExpression outer commons grp schemas params from
549+ -- ^ intermediate virtual table
498550 -> Query outer commons schemas params row
499−select_ list = select (List list)
551+select_ = select . List
500552
501553-- | After the select list has been processed, the result table can
502554-- be subject to the elimination of duplicate rows using `selectDistinct`.
503555selectDistinct
504556 :: (SListI columns, columns ~ (col ': cols))
505− => Selection outer 'Ungrouped commons schemas params from columns
506− -- ^ select list
507− -> TableExpression outer 'Ungrouped commons schemas params from
557+ => Selection outer commons grp schemas params from columns
558+ -- ^ selection
559+ -> TableExpression outer commons grp schemas params from
508560 -- ^ intermediate virtual table
509561 -> Query outer commons schemas params columns
510562selectDistinct selection tabexpr = UnsafeQuery $
@@ -512,14 +564,65 @@ selectDistinct selection tabexpr = UnsafeQuery $
512564 <+> renderSQL selection
513565 <+> renderSQL tabexpr
514566
567+-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead
568+-- of a general `Selection`.
515569selectDistinct_
516570 :: (SListI columns, columns ~ (col ': cols))
517− => NP (Aliased (Expression outer 'Ungrouped commons schemas params from)) columns
571+ => NP (Aliased (Expression outer commons grp schemas params from)) columns
518572 -- ^ select list
519− -> TableExpression outer 'Ungrouped commons schemas params from
573+ -> TableExpression outer commons grp schemas params from
574+ -- ^ 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
598+ -- ^ 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
520623 -- ^ intermediate virtual table
521624 -> Query outer commons schemas params columns
522−selectDistinct_ list = select (List list)
625+selectDistinctOn_ distincts = selectDistinctOn distincts . List
523626
524627-- | `values` computes a row value or set of row values
525628-- specified by value expressions. It is most commonly used
@@ -532,8 +635,8 @@ selectDistinct_ list = select (List list)
532635-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")
533636values
534637 :: SListI cols
535− => NP (Aliased (Expression outer 'Ungrouped commons schemas params '[] )) cols
536− -> [NP (Aliased (Expression outer 'Ungrouped commons schemas params '[] )) cols]
638+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
639+ -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]
537640 -- ^ When more than one row is specified, all the rows must
538641 -- must have the same number of elements
539642 -> Query outer commons schemas params cols
@@ -547,7 +650,7 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"
547650 <+> parenthesized (renderCommaSeparated renderAliasPart rw)
548651 where
549652 renderAliasPart, renderValuePart
550− :: Aliased (Expression outer 'Ungrouped commons schemas params '[] ) ty -> ByteString
653+ :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString
551654 renderAliasPart (_ `As` name) = renderSQL name
552655 renderValuePart (value `As` _) = renderSQL value
553656
@@ -555,7 +658,7 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"
555658-- specified by value expressions.
556659values_
557660 :: SListI cols
558− => NP (Aliased (Expression outer 'Ungrouped commons schemas params '[] )) cols
661+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols
559662 -- ^ one row of values
560663 -> Query outer commons schemas params cols
561664values_ rw = values rw []
@@ -572,8 +675,8 @@ Table Expressions
572675-- can be used to modify or combine base tables in various ways.
573676data TableExpression
574677 (outer :: FromType)
575− (grp :: Grouping)
576678 (commons :: FromType)
679+ (grp :: Grouping)
577680 (schemas :: SchemasType)
578681 (params :: [NullityType])
579682 (from :: FromType)
@@ -581,7 +684,7 @@ data TableExpression
581684 { fromClause :: FromClause outer commons schemas params from
582685 -- ^ A table reference that can be a table name, or a derived table such
583686 -- as a subquery, a @JOIN@ construct, or complex combinations of these.
584− , whereClause :: [Condition outer 'Ungrouped commons schemas params from]
687+ , whereClause :: [Condition outer commons 'Ungrouped schemas params from]
585688 -- ^ optional search coditions, combined with `.&&`. After the processing
586689 -- of the `fromClause` is done, each row of the derived virtual table
587690 -- is checked against the search condition. If the result of the
@@ -597,13 +700,13 @@ data TableExpression
597700 -- set of rows having common values into one group row that represents all
598701 -- rows in the group. This is done to eliminate redundancy in the output
599702 -- and/or compute aggregates that apply to these groups.
600− , havingClause :: HavingClause outer grp commons schemas params from
703+ , havingClause :: HavingClause outer commons grp schemas params from
601704 -- ^ If a table has been grouped using `groupBy`, but only certain groups
602705 -- are of interest, the `havingClause` can be used, much like a
603706 -- `whereClause`, to eliminate groups from the result. Expressions in the
604707 -- `havingClause` can refer both to grouped expressions and to ungrouped
605708 -- expressions (which necessarily involve an aggregate function).
606− , orderByClause :: [SortExpression outer grp commons schemas params from]
709+ , orderByClause :: [SortExpression outer commons grp schemas params from]
607710 -- ^ The `orderByClause` is for optional sorting. When more than one
608711 -- `SortExpression` is specified, the later (right) values are used to sort
609712 -- rows that are equal according to the earlier (left) values.
@@ -620,7 +723,7 @@ data TableExpression
620723 } deriving (GHC.Generic)
621724
622725-- | Render a `TableExpression`
623−instance RenderSQL (TableExpression outer grp commons schemas params from) where
726+instance RenderSQL (TableExpression outer commons grp schemas params from) where
624727 renderSQL
625728 (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat
626729 [ "FROM ", renderSQL frm'
@@ -653,29 +756,29 @@ instance RenderSQL (TableExpression outer grp commons schemas params from) where
653756-- to match the left-to-right sequencing of their placement in SQL.
654757from
655758 :: FromClause outer commons schemas params from -- ^ table reference
656− -> TableExpression outer 'Ungrouped commons schemas params from
657−from tab = TableExpression tab [] NoGroups NoHaving [] [] []
759+ -> TableExpression outer commons 'Ungrouped schemas params from
760+from tab = TableExpression tab [] noGroups NoHaving [] [] []
658761
659762-- | A `where_` is an endomorphism of `TableExpression`s which adds a
660763-- search condition to the `whereClause`.
661764where_
662− :: Condition outer 'Ungrouped commons schemas params from -- ^ filtering condition
663− -> TableExpression outer grp commons schemas params from
664− -> TableExpression outer grp commons schemas params from
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
665768where_ wh rels = rels {whereClause = wh : whereClause rels}
666769
667770-- | A `groupBy` is a transformation of `TableExpression`s which switches
668−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform
771+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform
669772-- a "grand total" aggregation query.
670773groupBy
671774 :: SListI bys
672775 => NP (By from) bys -- ^ grouped columns
673− -> TableExpression outer 'Ungrouped commons schemas params from
674− -> TableExpression outer ('Grouped bys) commons schemas params from
776+ -> TableExpression outer commons 'Ungrouped schemas params from
777+ -> TableExpression outer commons ('Grouped bys) schemas params from
675778groupBy bys rels = TableExpression
676779 { fromClause = fromClause rels
677780 , whereClause = whereClause rels
678− , groupByClause = Group bys
781+ , groupByClause = group bys
679782 , havingClause = Having []
680783 , orderByClause = []
681784 , limitClause = limitClause rels
@@ -685,9 +788,9 @@ groupBy bys rels = TableExpression
685788-- | A `having` is an endomorphism of `TableExpression`s which adds a
686789-- search condition to the `havingClause`.
687790having
688− :: Condition outer ('Grouped bys) commons schemas params from -- ^ having condition
689− -> TableExpression outer ('Grouped bys) commons schemas params from
690− -> TableExpression outer ('Grouped bys) commons schemas params from
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
691794having hv rels = rels
692795 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }
693796
@@ -698,165 +801,18 @@ instance OrderBy TableExpression where
698801-- `limitClause`.
699802limit
700803 :: Word64 -- ^ limit parameter
701− -> TableExpression outer grp commons schemas params from
702− -> TableExpression outer grp commons schemas params from
804+ -> TableExpression outer commons grp schemas params from
805+ -> TableExpression outer commons grp schemas params from
703806limit lim rels = rels {limitClause = lim : limitClause rels}
704807
705808-- | An `offset` is an endomorphism of `TableExpression`s which adds to the
706809-- `offsetClause`.
707810offset
708811 :: Word64 -- ^ offset parameter
709− -> TableExpression outer grp commons schemas params from
710− -> TableExpression outer grp commons schemas params from
812+ -> TableExpression outer commons grp schemas params from
813+ -> TableExpression outer commons grp schemas params from
711814offset off rels = rels {offsetClause = off : offsetClause rels}
712815
713−{-----------------------------------------
714−JSON stuff
715−-----------------------------------------}
716−
717−unsafeSetOfFunction
718− :: ByteString
719− -> Expression outer 'Ungrouped commons schemas params '[] ty
720− -> Query outer commons schemas params row
721−unsafeSetOfFunction fun expr = UnsafeQuery $
722− "SELECT * FROM " <> fun <> "(" <> renderSQL expr <> ")"
723−
724−-- | Expand an array to a set of rows
725−unnest
726− :: Expression outer 'Ungrouped commons schemas params '[] (nullity ('PGvararray ty))
727− -> Query outer commons schemas params '[ "unnest" ::: ty ]
728−unnest = unsafeSetOfFunction "unnest"
729−
730−-- | Expands the outermost JSON object into a set of key/value pairs.
731−jsonEach
732− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json object
733− -> Query outer commons schemas params
734− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]
735−jsonEach = unsafeSetOfFunction "json_each"
736−
737−-- | Expands the outermost binary JSON object into a set of key/value pairs.
738−jsonbEach
739− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb object
740− -> Query outer commons schemas params
741− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjsonb]
742−jsonbEach = unsafeSetOfFunction "jsonb_each"
743−
744−-- | Expands the outermost JSON object into a set of key/value pairs.
745−jsonEachAsText
746− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json object
747− -> Query outer commons schemas params
748− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]
749−jsonEachAsText = unsafeSetOfFunction "json_each_text"
750−
751−-- | Expands the outermost binary JSON object into a set of key/value pairs.
752−jsonbEachAsText
753− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb object
754− -> Query outer commons schemas params
755− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]
756−jsonbEachAsText = unsafeSetOfFunction "jsonb_each_text"
757−
758−-- | Returns set of keys in the outermost JSON object.
759−jsonObjectKeys
760− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json object
761− -> Query outer commons schemas params '["json_object_keys" ::: 'NotNull 'PGtext]
762−jsonObjectKeys = unsafeSetOfFunction "json_object_keys"
763−
764−-- | Returns set of keys in the outermost JSON object.
765−jsonbObjectKeys
766− :: Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb object
767− -> Query outer commons schemas params '["jsonb_object_keys" ::: 'NotNull 'PGtext]
768−jsonbObjectKeys = unsafeSetOfFunction "jsonb_object_keys"
769−
770−unsafePopulateFunction
771− :: ByteString
772− -> TypeExpression schemas (nullity ('PGcomposite row))
773− -> Expression outer 'Ungrouped commons schemas params '[] ty
774− -> Query outer commons schemas params row
775−unsafePopulateFunction fun ty expr = UnsafeQuery $
776− "SELECT * FROM " <> fun <> "("
777− <> "null::" <> renderSQL ty <> ", "
778− <> renderSQL expr <> ")"
779−
780−-- | Expands the JSON expression to a row whose columns match the record
781−-- type defined by the given table.
782−jsonPopulateRecord
783− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type
784− -> Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json object
785− -> Query outer commons schemas params row
786−jsonPopulateRecord = unsafePopulateFunction "json_populate_record"
787−
788−-- | Expands the binary JSON expression to a row whose columns match the record
789−-- type defined by the given table.
790−jsonbPopulateRecord
791− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type
792− -> Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb object
793− -> Query outer commons schemas params row
794−jsonbPopulateRecord = unsafePopulateFunction "jsonb_populate_record"
795−
796−-- | Expands the outermost array of objects in the given JSON expression to a
797−-- set of rows whose columns match the record type defined by the given table.
798−jsonPopulateRecordSet
799− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type
800− -> Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json array
801− -> Query outer commons schemas params row
802−jsonPopulateRecordSet = unsafePopulateFunction "json_populate_record_set"
803−
804−-- | Expands the outermost array of objects in the given binary JSON expression
805−-- to a set of rows whose columns match the record type defined by the given
806−-- table.
807−jsonbPopulateRecordSet
808− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type
809− -> Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb array
810− -> Query outer commons schemas params row
811−jsonbPopulateRecordSet = unsafePopulateFunction "jsonb_populate_record_set"
812−
813−unsafeRecordFunction
814− :: (SListI record, json `In` PGJsonType)
815− => ByteString
816− -> Expression outer 'Ungrouped commons schemas params '[] (nullity json)
817− -> NP (Aliased (TypeExpression schemas)) record
818− -> Query outer commons schemas params record
819−unsafeRecordFunction fun expr types = UnsafeQuery $
820− "SELECT * FROM " <> fun <> "("
821− <> renderSQL expr <> ")"
822− <+> "AS" <+> "x" <> parenthesized (renderCommaSeparated renderTy types)
823− where
824− renderTy :: Aliased (TypeExpression schemas) ty -> ByteString
825− renderTy (ty `As` alias) =
826− renderSQL alias <+> renderSQL ty
827−
828−-- | Builds an arbitrary record from a JSON object.
829−jsonToRecord
830− :: SListI record
831− => Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json object
832− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types
833− -> Query outer commons schemas params record
834−jsonToRecord = unsafeRecordFunction "json_to_record"
835−
836−-- | Builds an arbitrary record from a binary JSON object.
837−jsonbToRecord
838− :: SListI record
839− => Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb object
840− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types
841− -> Query outer commons schemas params record
842−jsonbToRecord = unsafeRecordFunction "jsonb_to_record"
843−
844−-- | Builds an arbitrary set of records from a JSON array of objects.
845−jsonToRecordSet
846− :: SListI record
847− => Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjson) -- ^ json array
848− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types
849− -> Query outer commons schemas params record
850−jsonToRecordSet = unsafeRecordFunction "json_to_record_set"
851−
852−-- | Builds an arbitrary set of records from a binary JSON array of objects.
853−jsonbToRecordSet
854− :: SListI record
855− => Expression outer 'Ungrouped commons schemas params '[] (nullity 'PGjsonb) -- ^ jsonb array
856− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types
857− -> Query outer commons schemas params record
858−jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"
859−
860816{-----------------------------------------
861817FROM clauses
862818-----------------------------------------}
@@ -883,7 +839,7 @@ table (tab `As` alias) = UnsafeFromClause $
883839subquery
884840 :: Aliased (Query outer commons schemas params) query
885841 -> FromClause outer commons schemas params '[query]
886−subquery = UnsafeFromClause . renderAliased (parenthesized . renderQuery)
842+subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)
887843
888844-- | `view` derives a table from a `View`.
889845view
@@ -901,11 +857,16 @@ common
901857common (cte `As` alias) = UnsafeFromClause $
902858 renderSQL cte <+> "AS" <+> renderSQL alias
903859
904−{- | @left & crossJoin right@. For every possible combination of rows from
905− @left@ and @right@ (i.e., a Cartesian product), the joined table will contain
906− a row consisting of all columns in @left@ followed by all columns in @right@.
907− If the tables have @n@ and @m@ rows respectively, the joined table will
908− have @n * m@ rows.
860+instance Additional (FromClause outer commons schemas params) where
861+ also right left = UnsafeFromClause $
862+ renderSQL left <> ", " <> renderSQL right
863+
864+{- |
865+@left & crossJoin right@. For every possible combination of rows from
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.
909870-}
910871crossJoin
911872 :: FromClause outer commons schemas params right
@@ -922,7 +883,7 @@ the @on@ condition.
922883innerJoin
923884 :: FromClause outer commons schemas params right
924885 -- ^ right
925− -> Condition outer 'Ungrouped commons schemas params (Join left right)
886+ -> Condition outer commons 'Ungrouped schemas params (Join left right)
926887 -- ^ @on@ condition
927888 -> FromClause outer commons schemas params left
928889 -- ^ left
@@ -939,7 +900,7 @@ innerJoin right on left = UnsafeFromClause $
939900leftOuterJoin
940901 :: FromClause outer commons schemas params right
941902 -- ^ right
942− -> Condition outer 'Ungrouped commons schemas params (Join left right)
903+ -> Condition outer commons 'Ungrouped schemas params (Join left right)
943904 -- ^ @on@ condition
944905 -> FromClause outer commons schemas params left
945906 -- ^ left
@@ -957,7 +918,7 @@ leftOuterJoin right on left = UnsafeFromClause $
957918rightOuterJoin
958919 :: FromClause outer commons schemas params right
959920 -- ^ right
960− -> Condition outer 'Ungrouped commons schemas params (Join left right)
921+ -> Condition outer commons 'Ungrouped schemas params (Join left right)
961922 -- ^ @on@ condition
962923 -> FromClause outer commons schemas params left
963924 -- ^ left
@@ -976,7 +937,7 @@ rightOuterJoin right on left = UnsafeFromClause $
976937fullOuterJoin
977938 :: FromClause outer commons schemas params right
978939 -- ^ right
979− -> Condition outer 'Ungrouped commons schemas params (Join left right)
940+ -> Condition outer commons 'Ungrouped schemas params (Join left right)
980941 -- ^ @on@ condition
981942 -> FromClause outer commons schemas params left
982943 -- ^ left
@@ -1031,131 +992,42 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])
1031992-- done on @NoGroups@ while all output `Expression`s must be aggregated
1032993-- in @Group Nil@. In general, all output `Expression`s in the
1033994-- complement of @bys@ must be aggregated in @Group bys@.
1034−data GroupByClause grp from where
1035− NoGroups :: GroupByClause 'Ungrouped from
1036− Group
1037− :: SListI bys
1038− => NP (By from) bys
1039− -> GroupByClause ('Grouped bys) from
1040−
1041−-- | Renders a `GroupByClause`.
995+newtype GroupByClause grp from = UnsafeGroupByClause
996+ { renderGroupByClause :: ByteString }
997+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
1042998instance RenderSQL (GroupByClause grp from) where
1043− renderSQL = \case
1044− NoGroups -> ""
1045− Group Nil -> ""
1046− Group bys -> " GROUP BY" <+> renderCommaSeparated renderSQL bys
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'
10471009
10481010-- | A `HavingClause` is used to eliminate groups that are not of interest.
10491011-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`
10501012-- `TableExpression` must use `Having` whose conditions are combined with
10511013-- `.&&`.
1052−data HavingClause outer grp commons schemas params from where
1053− NoHaving :: HavingClause outer 'Ungrouped commons schemas params from
1014+data HavingClause outer commons grp schemas params from where
1015+ NoHaving :: HavingClause outer commons 'Ungrouped schemas params from
10541016 Having
1055− :: [Condition outer ('Grouped bys) commons schemas params from]
1056− -> HavingClause outer ('Grouped bys) commons schemas params from
1057−deriving instance Show (HavingClause outer grp commons schemas params from)
1058−deriving instance Eq (HavingClause outer grp commons schemas params from)
1059−deriving instance Ord (HavingClause outer grp commons schemas params from)
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)
10601022
10611023-- | Render a `HavingClause`.
1062−instance RenderSQL (HavingClause outer grp commons schemas params from) where
1024+instance RenderSQL (HavingClause outer commons grp schemas params from) where
10631025 renderSQL = \case
10641026 NoHaving -> ""
10651027 Having [] -> ""
10661028 Having conditions ->
10671029 " HAVING" <+> commaSeparated (renderSQL <$> conditions)
10681030
1069−{- |
1070−The argument of `exists` is an arbitrary subquery. The subquery is evaluated
1071−to determine whether it returns any rows. If it returns at least one row,
1072−the result of `exists` is `true`; if the subquery returns no rows,
1073−the result of `exists` is `false`.
1074−
1075−The subquery can refer to variables from the surrounding query,
1076−which will act as constants during any one evaluation of the subquery.
1077−
1078−The subquery will generally only be executed long enough to determine whether
1079−at least one row is returned, not all the way to completion.
1080−-}
1081−exists
1082− :: Query (Join outer from) commons schemas params row
1083− -> Condition outer grp commons schemas params from
1084−exists query = UnsafeExpression $ "EXISTS" <+> parenthesized (renderSQL query)
1085−
1086−type Operator ty1 ty2 ty3
1087− = forall outer grp commons schemas params from
1088− . Expression outer grp commons schemas params from ty1
1089− -> Expression outer grp commons schemas params from ty2
1090− -> Expression outer grp commons schemas params from ty3
1091−
1092−{- |
1093−The right-hand side is a parenthesized subquery, which must return
1094−exactly one column. The left-hand expression is evaluated and compared to each
1095−row of the subquery result using the given `Operator`,
1096−which must yield a Boolean result. The result of `subAll` is `true`
1097−if all rows yield true (including the case where the subquery returns no rows).
1098−The result is `false` if any `false` result is found.
1099−The result is `null_` if no comparison with a subquery row returns `false`,
1100−and at least one comparison returns `null_`.
1101−
1102−>>> printSQL $ subAll true (.==) (values_ (true `as` #foo))
1103−(TRUE = ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo")))
1104−-}
1105−subAll
1106− :: Expression outer grp commons schemas params from ty1 -- ^ expression
1107− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator
1108− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery
1109− -> Condition outer grp commons schemas params from
1110−subAll expr (?) qry = expr ?
1111− (UnsafeExpression $ "ALL" <+> parenthesized (renderSQL qry))
1112−
1113−{- |
1114−The right-hand side is a parenthesized subquery, which must return exactly one column.
1115−The left-hand expression is evaluated and compared to each row of the subquery result
1116−using the given `Operator`, which must yield a Boolean result. The result of `subAny` is `true`
1117−if any `true` result is obtained. The result is `false` if no true result is found
1118−(including the case where the subquery returns no rows).
1119−
1120−>>> printSQL $ subAll "foo" like (values_ ("foobar" `as` #foo))
1121−(E'foo' LIKE ALL (SELECT * FROM (VALUES (E'foobar')) AS t ("foo")))
1122−-}
1123−subAny
1124− :: Expression outer grp commons schemas params from ty1 -- ^ expression
1125− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator
1126− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery
1127− -> Condition outer grp commons schemas params from
1128−subAny expr (?) qry = expr ?
1129− (UnsafeExpression $ "ANY" <+> parenthesized (renderSQL qry))
1130−
1131−{- |
1132−The result is `true` if the left-hand expression's result is equal
1133−to any of the right-hand expressions.
1134−
1135−>>> printSQL $ true `in_` [true, false, null_]
1136−TRUE IN (TRUE, FALSE, NULL)
1137−-}
1138−in_
1139− :: Expression outer grp commons schemas params from ty -- ^ expression
1140− -> [Expression outer grp commons schemas params from ty]
1141− -> Condition outer grp commons schemas params from
1142−expr `in_` exprs = UnsafeExpression $ renderSQL expr <+> "IN"
1143− <+> parenthesized (commaSeparated (renderSQL <$> exprs))
1144−
1145−{- |
1146−The result is `true` if the left-hand expression's result is not equal
1147−to any of the right-hand expressions.
1148−
1149−>>> printSQL $ true `notIn` [false, null_]
1150−TRUE NOT IN (FALSE, NULL)
1151−-}
1152−notIn
1153− :: Expression outer grp commons schemas params from ty -- ^ expression
1154− -> [Expression outer grp commons schemas params from ty]
1155− -> Condition outer grp commons schemas params from
1156−expr `notIn` exprs = UnsafeExpression $ renderSQL expr <+> "NOT IN"
1157− <+> parenthesized (commaSeparated (renderSQL <$> exprs))
1158−
11591031-- | A `CommonTableExpression` is an auxiliary statement in a `with` clause.
11601032data CommonTableExpression statement
11611033 (schemas :: SchemasType)
@@ -1177,8 +1049,8 @@ instance
11771049 , commons1 ~ (cte ::: common ': commons)
11781050 ) => Aliasable cte
11791051 (statement commons schemas params common)
1180− (AlignedList (CommonTableExpression statement schemas params) commons commons1) where
1181− statement `as` cte = single (statement `as` cte)
1052+ (Path (CommonTableExpression statement schemas params) commons commons1) where
1053+ statement `as` cte = csingleton (statement `as` cte)
11821054
11831055instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL
11841056 (CommonTableExpression statement schemas params commons0 commons1) where
@@ -1190,7 +1062,7 @@ instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL
11901062-- defining temporary tables that exist just for one query.
11911063class With statement where
11921064 with
1193− :: AlignedList (CommonTableExpression statement schemas params) commons0 commons1
1065+ :: Path (CommonTableExpression statement schemas params) commons0 commons1
11941066 -- ^ common table expressions
11951067 -> statement commons1 schemas params row
11961068 -- ^ larger query
@@ -1198,4 +1070,29 @@ class With statement where
11981070instance With (Query outer) where
11991071 with Done query = query
12001072 with ctes query = UnsafeQuery $
1201− "WITH" <+> renderSQL ctes <+> renderSQL query
1073+ "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL query
1074+
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
squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+39−6
@@ -10,31 +10,37 @@ Rendering helper functions.
1010
1111{-# LANGUAGE
1212 AllowAmbiguousTypes
13+ , ConstraintKinds
1314 , FlexibleContexts
15+ , LambdaCase
1416 , MagicHash
1517 , OverloadedStrings
1618 , PolyKinds
1719 , RankNTypes
1820 , ScopedTypeVariables
21+ , TypeApplications
1922#-}
2023
2124module Squeal.PostgreSQL.Render
2225 ( -- * Render
23− parenthesized
26+ RenderSQL (..)
27+ , printSQL
28+ , escape
29+ , parenthesized
30+ , bracketed
2431 , (<+>)
2532 , commaSeparated
2633 , doubleQuoted
2734 , singleQuotedText
2835 , singleQuotedUtf8
2936 , renderCommaSeparated
37+ , renderCommaSeparatedConstraint
3038 , renderCommaSeparatedMaybe
3139 , renderNat
3240 , renderSymbol
33− , RenderSQL (..)
34− , printSQL
3541 ) where
3642
37−import Control.Monad.Base
43+import Control.Monad.IO.Class (MonadIO (..))
3844import Data.ByteString (ByteString)
3945import Data.Maybe (catMaybes)
4046import Data.Monoid ((<>))
@@ -52,6 +58,10 @@ import qualified Data.ByteString.Char8 as Char8
5258parenthesized :: ByteString -> ByteString
5359parenthesized str = "(" <> str <> ")"
5460
61+-- | Square bracket a `ByteString`
62+bracketed :: ByteString -> ByteString
63+bracketed str = "[" <> str <> "]"
64+
5565-- | Concatenate two `ByteString`s with a space between.
5666(<+>) :: ByteString -> ByteString -> ByteString
5767infixr 7 <+>
@@ -84,6 +94,16 @@ renderCommaSeparated render
8494 . hcollapse
8595 . hmap (K . render)
8696
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+
87107-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping
88108-- `Nothing`s.
89109renderCommaSeparatedMaybe
@@ -108,5 +128,18 @@ renderSymbol = fromString (symbolVal' (proxy# :: Proxy# s))
108128class RenderSQL sql where renderSQL :: sql -> ByteString
109129
110130-- | Print SQL.
111−printSQL :: (RenderSQL sql, MonadBase IO io) => sql -> io ()
112−printSQL = liftBase . Char8.putStrLn . renderSQL
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]
squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+181−371
@@ -1,16 +1,15 @@
11{-|
22Module: Squeal.PostgreSQL.Schema
33Description: Embedding of PostgreSQL type and alias system
4−Copyright: (c) Eitan Chatav, 2017
4+Copyright: (c) Eitan Chatav, 2019
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
8−This module provides a type-level DSL for kinds of Postgres types,
8+`Squeal.PostgreSQL.Schema` 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 #-}
1413{-# LANGUAGE
1514 AllowAmbiguousTypes
1615 , ConstraintKinds
@@ -45,6 +44,10 @@ module Squeal.PostgreSQL.Schema
4544 , ColumnsType
4645 , TableType
4746 , SchemumType (..)
47+ , IndexType (..)
48+ , FunctionType
49+ , OperatorType (..)
50+ , ReturnsType (..)
4851 , SchemaType
4952 , SchemasType
5053 , Public
@@ -54,52 +57,30 @@ module Squeal.PostgreSQL.Schema
5457 , TableConstraint (..)
5558 , TableConstraints
5659 , Uniquely
57− -- * Aliases
58− , (:::)
59− , Alias (..)
60− , IsLabel (..)
61− , Aliased (As)
62− , Aliasable (as)
63− , renderAliased
64− , Has
65− , HasUnique
66− , HasAll
67− , QualifiedAlias (..)
68− , IsQualified (..)
69− , HasIn
70− , IsNotElem
71− , AllUnique
72− , DefaultAliasable (..)
7360 -- * Enumerated Labels
7461 , IsPGlabel (..)
7562 , PGlabel (..)
76− -- * Grouping
77− , Grouping (..)
78− , GroupedBy
79− -- * Aligned lists
80− , AlignedList (..)
81− , single
8263 -- * Data Definitions
8364 , Create
65+ , CreateIfNotExists
66+ , CreateOrReplace
8467 , Drop
68+ , DropSchemum
69+ , DropIfExists
70+ , DropSchemumIfExists
8571 , Alter
72+ , AlterIfExists
8673 , Rename
74+ , RenameIfExists
75+ , ConstraintInvolves
8776 , DropIfConstraintsInvolve
88− -- * Lists
89− , Join
90− , disjoin
91− , Elem
92− , In
93− , Length
77+ , IsNotElem
78+ , AllUnique
9479 -- * Type Classifications
95− , HasOid (..)
9680 , PGNum
9781 , PGIntegral
9882 , PGFloating
9983 , PGTypeOf
100− , PGArrayOf
101− , PGArray
102− , PGTextArray
10384 , PGJsonType
10485 , PGJsonKey
10586 , SamePGType
@@ -116,25 +97,22 @@ module Squeal.PostgreSQL.Schema
11697 ) where
11798
11899import Control.Category
119−import Control.DeepSeq
120−import Data.ByteString (ByteString)
121100import Data.Kind
122101import Data.Monoid hiding (All)
123−import Data.String
124102import Data.Type.Bool
125−import Data.Word (Word32)
126103import Generics.SOP
127−import GHC.OverloadedLabels
128104import GHC.TypeLits
129105import Prelude hiding (id, (.))
130106
131−import qualified GHC.Generics as GHC
132−
107+import Squeal.PostgreSQL.Alias
108+import Squeal.PostgreSQL.List
133109import Squeal.PostgreSQL.Render
134110
111+-- $setup
112+-- >>> import Squeal.PostgreSQL
113+
135114-- | `PGType` is the promoted datakind of PostgreSQL types.
136115--
137−-- >>> import Squeal.PostgreSQL.Schema
138116-- >>> :kind 'PGbool
139117-- 'PGbool :: PGType
140118data PGType
@@ -164,36 +142,12 @@ data PGType
164142 | PGfixarray [Nat] NullityType -- ^ fixed length array
165143 | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.
166144 | 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).
167149 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types
168150
169−-- | The object identifier of a `PGType`.
170−--
171−-- >>> :set -XTypeApplications
172−-- >>> oid @'PGbool
173−-- 16
174−class HasOid (ty :: PGType) where oid :: Word32
175−instance HasOid 'PGbool where oid = 16
176−instance HasOid 'PGint2 where oid = 21
177−instance HasOid 'PGint4 where oid = 23
178−instance HasOid 'PGint8 where oid = 20
179−instance HasOid 'PGnumeric where oid = 1700
180−instance HasOid 'PGfloat4 where oid = 700
181−instance HasOid 'PGfloat8 where oid = 701
182−instance HasOid ('PGchar n) where oid = 18
183−instance HasOid ('PGvarchar n) where oid = 1043
184−instance HasOid 'PGtext where oid = 25
185−instance HasOid 'PGbytea where oid = 17
186−instance HasOid 'PGtimestamp where oid = 1114
187−instance HasOid 'PGtimestamptz where oid = 1184
188−instance HasOid 'PGdate where oid = 1082
189−instance HasOid 'PGtime where oid = 1083
190−instance HasOid 'PGtimetz where oid = 1266
191−instance HasOid 'PGinterval where oid = 1186
192−instance HasOid 'PGuuid where oid = 2950
193−instance HasOid 'PGinet where oid = 869
194−instance HasOid 'PGjson where oid = 114
195−instance HasOid 'PGjsonb where oid = 3802
196−
197151-- | `NullityType` encodes the potential presence or definite absence of a
198152-- @NULL@ allowing operations which are sensitive to such to be well typed.
199153--
@@ -212,11 +166,6 @@ data NullityType
212166type (:=>) constraint ty = '(constraint,ty)
213167infixr 7 :=>
214168
215−-- | The alias operator `:::` is like a promoted version of `As`,
216−-- a type level pair between an alias and some type.
217−type (:::) (alias :: Symbol) ty = '(alias,ty)
218−infixr 6 :::
219−
220169-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.
221170-- A column can be assigned a default value.
222171-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also
@@ -311,9 +260,19 @@ type FromType = [(Symbol,RowType)]
311260
312261-- | `ColumnsToRow` removes column constraints.
313262type family ColumnsToRow (columns :: ColumnsType) :: RowType where
314− ColumnsToRow '[] = '[]
315− ColumnsToRow (column ::: constraint :=> ty ': columns) =
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) =
316274 column ::: ty ': ColumnsToRow columns
275+ ColumnsToRow '[] = '[]
317276
318277-- | `TableToColumns` removes table constraints.
319278type family TableToColumns (table :: TableType) :: ColumnsType where
@@ -323,212 +282,6 @@ type family TableToColumns (table :: TableType) :: ColumnsType where
323282type family TableToRow (table :: TableType) :: RowType where
324283 TableToRow tab = ColumnsToRow (TableToColumns tab)
325284
326−-- | `Grouping` is an auxiliary namespace, created by
327−-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used
328−-- for typesafe aggregation
329−data Grouping
330− = Ungrouped -- ^ no aggregation permitted
331− | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped
332−
333−{- | A `GroupedBy` constraint indicates that a table qualified column is
334−a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,
335−may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.
336−-}
337−class (KnownSymbol table, KnownSymbol column)
338− => GroupedBy table column bys where
339−instance {-# OVERLAPPING #-} (KnownSymbol table, KnownSymbol column)
340− => GroupedBy table column ('(table,column) ': bys)
341−instance {-# OVERLAPPABLE #-}
342− ( KnownSymbol table
343− , KnownSymbol column
344− , GroupedBy table column bys
345− ) => GroupedBy table column (tabcol ': bys)
346−
347−-- | `Alias`es are proxies for a type level string or `Symbol`
348−-- and have an `IsLabel` instance so that with @-XOverloadedLabels@
349−--
350−-- >>> :set -XOverloadedLabels
351−-- >>> #foobar :: Alias "foobar"
352−-- Alias
353−data Alias (alias :: Symbol) = Alias
354− deriving (Eq,GHC.Generic,Ord,Show,NFData)
355−instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where
356− fromLabel = Alias
357−instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where
358− fromLabel = fromLabel :* Nil
359−-- | >>> printSQL (#jimbob :: Alias "jimbob")
360−-- "jimbob"
361−instance KnownSymbol alias => RenderSQL (Alias alias) where
362− renderSQL = doubleQuoted . fromString . symbolVal
363−
364−-- | >>> import Generics.SOP (NP(..))
365−-- >>> printSQL (#jimbob :* #kandi :: NP Alias '["jimbob", "kandi"])
366−-- "jimbob", "kandi"
367−instance All KnownSymbol aliases => RenderSQL (NP Alias aliases) where
368− renderSQL
369− = commaSeparated
370− . hcollapse
371− . hcmap (Proxy @KnownSymbol) (K . renderSQL)
372−
373−-- | The `As` operator is used to name an expression. `As` is like a demoted
374−-- version of `:::`.
375−--
376−-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)
377−-- As (Just "hello") Alias
378−data Aliased expression aliased where
379− As
380− :: KnownSymbol alias
381− => expression ty
382− -> Alias alias
383− -> Aliased expression (alias ::: ty)
384−deriving instance Show (expression ty)
385− => Show (Aliased expression (alias ::: ty))
386−deriving instance Eq (expression ty)
387− => Eq (Aliased expression (alias ::: ty))
388−deriving instance Ord (expression ty)
389− => Ord (Aliased expression (alias ::: ty))
390−instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)
391− => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where
392− fromLabel = fromLabel @alias2 `As` fromLabel @alias1
393−
394−-- | The `Aliasable` class provides a way to scrap your `Nil`s
395−-- in an `NP` list of `Aliased` expressions.
396−class KnownSymbol alias => Aliasable alias expression aliased
397− | aliased -> expression
398− , aliased -> alias
399− where as :: expression -> Alias alias -> aliased
400−instance (KnownSymbol alias, aliased ~ (alias ::: ty)) => Aliasable alias
401− (expression ty)
402− (Aliased expression aliased)
403− where
404− as = As
405−instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias
406− (expression ty)
407− (NP (Aliased expression) tys)
408− where
409− expression `as` alias = expression `As` alias :* Nil
410−
411−-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")
412−-- >>> renderAliased renderMaybe (Just (3::Int) `As` #an_int)
413−-- "Just AS \"an_int\""
414−renderAliased
415− :: (forall ty. expression ty -> ByteString)
416− -> Aliased expression aliased
417− -> ByteString
418−renderAliased render (expression `As` alias) =
419− render expression <> " AS " <> renderSQL alias
420−
421−-- | @HasUnique alias fields field@ is a constraint that proves that
422−-- @fields@ is a singleton of @alias ::: field@.
423−type HasUnique alias fields field = fields ~ '[alias ::: field]
424−
425−-- | @Has alias fields field@ is a constraint that proves that
426−-- @fields@ has a field of @alias ::: field@, inferring @field@
427−-- from @alias@ and @fields@.
428−class KnownSymbol alias =>
429− Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)
430− | alias fields -> field where
431−instance {-# OVERLAPPING #-} KnownSymbol alias
432− => Has alias (alias ::: field ': fields) field
433−instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)
434− => Has alias (field' ': fields) field
435−
436−{-| @HasIn fields (alias ::: field)@ is a constraint that proves that
437−@fields@ has a field of @alias ::: field@. It is used in @UPDATE@s to
438−choose which subfields to update.
439−-}
440−class HasIn fields field where
441−instance (Has alias fields field) => HasIn fields (alias ::: field) where
442−
443−-- | Utility class for `AllUnique` to provide nicer error messages.
444−class IsNotElem x isElem where
445−instance IsNotElem x 'False where
446−instance (TypeError ( 'Text "Cannot assign to "
447− ':<>: 'ShowType alias
448− ':<>: 'Text " more than once"))
449− => IsNotElem '(alias, a) 'True where
450−
451−-- | No elem of @xs@ appears more than once, in the context of assignment.
452−class AllUnique (xs :: [(Symbol, a)]) where
453−instance AllUnique '[] where
454−instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where
455−
456−{- |
457−The `DefaultAliasable` class is intended to help with Scrap your Nils
458−for default inserts and updates.
459−-}
460−class KnownSymbol alias
461− => DefaultAliasable alias aliased | aliased -> alias where
462− defaultAs :: Alias alias -> aliased
463−
464−-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer
465−-- a list of @subfields@.
466−class
467− ( All KnownSymbol aliases
468− ) => HasAll
469− (aliases :: [Symbol])
470− (fields :: [(Symbol,kind)])
471− (subfields :: [(Symbol,kind)])
472− | aliases fields -> subfields where
473−instance {-# OVERLAPPING #-} HasAll '[] fields '[]
474−instance {-# OVERLAPPABLE #-}
475− (Has alias fields field, HasAll aliases fields subfields)
476− => HasAll (alias ': aliases) fields (alias ::: field ': subfields)
477−
478−-- | Analagous to `IsLabel`, the constraint
479−-- `IsQualified` defines `!` for a column alias qualified
480−-- by a table alias.
481−class IsQualified table column expression where
482− (!) :: Alias table -> Alias column -> expression
483− infixl 9 !
484−instance IsQualified table column (Alias table, Alias column) where (!) = (,)
485−
486−{-| `QualifiedAlias`es enables multi-schema support by allowing a reference
487−to a `Table`, `Typedef` or `View` to be qualified by their schemas. By default,
488−a qualifier of @public@ is provided.
489−
490−>>> :{
491−let
492− alias1 :: QualifiedAlias "sch" "tab"
493− alias1 = #sch ! #tab
494− alias2 :: QualifiedAlias "public" "vw"
495− alias2 = #vw
496−in printSQL alias1 >> printSQL alias2
497−:}
498−"sch"."tab"
499−"vw"
500−-}
501−data QualifiedAlias (qualifier :: Symbol) (alias :: Symbol) = QualifiedAlias
502− deriving (Eq,GHC.Generic,Ord,Show,NFData)
503−instance (q ~ q', a ~ a') => IsQualified q a (QualifiedAlias q' a') where
504− _!_ = QualifiedAlias
505−instance (q' ~ "public", a ~ a') => IsLabel a (QualifiedAlias q' a') where
506− fromLabel = QualifiedAlias
507−instance (q0 ~ q1, a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>
508− IsQualified q0 a0 (Aliased (QualifiedAlias q1) (a1 ::: a2)) where
509− _!_ = QualifiedAlias `As` Alias
510−instance (q ~ "public", a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>
511− IsLabel a0 (Aliased (QualifiedAlias q) (a1 ::: a2)) where
512− fromLabel = QualifiedAlias `As` Alias
513−
514−instance (KnownSymbol q, KnownSymbol a)
515− => RenderSQL (QualifiedAlias q a) where
516− renderSQL _ =
517− let
518− qualifier = renderSQL (Alias @q)
519− alias = renderSQL (Alias @a)
520− in
521− if qualifier == "\"public\"" then alias else qualifier <> "." <> alias
522−
523−-- | @Elem@ is a promoted `Data.List.elem`.
524−type family Elem x xs where
525− Elem x '[] = 'False
526− Elem x (x ': xs) = 'True
527− Elem x (_ ': xs) = Elem x xs
528−
529−-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.
530−type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True
531−
532285-- | Numeric Postgres types.
533286type PGNum =
534287 '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]
@@ -539,37 +292,6 @@ type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]
539292-- | Integral Postgres types.
540293type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]
541294
542−-- | Error message helper for displaying unavailable\/unknown\/placeholder type
543−-- variables whose kind is known.
544−type Placeholder k = 'Text "(_::" :<>: 'ShowType k :<>: 'Text ")"
545−
546−type ErrArrayOf arr ty = arr :<>: 'Text " " :<>: ty
547−type ErrPGfixarrayOf t = ErrArrayOf ('ShowType 'PGfixarray :<>: 'Text " " :<>: Placeholder Nat) t
548−type ErrPGvararrayOf t = ErrArrayOf ('ShowType 'PGvararray) t
549−
550−-- | Ensure a type is a valid array type.
551−type family PGArray name arr :: Constraint where
552− PGArray name ('PGvararray x) = ()
553− PGArray name ('PGfixarray n x) = ()
554− PGArray name val = TypeError
555− ('Text name :<>: 'Text ": Unsatisfied PGArray constraint. Expected either: "
556− :$$: 'Text " • " :<>: ErrPGvararrayOf (Placeholder PGType)
557− :$$: 'Text " • " :<>: ErrPGfixarrayOf (Placeholder PGType)
558− :$$: 'Text "But got: " :<>: 'ShowType val)
559−
560−-- | Ensure a type is a valid array type with a specific element type.
561−type family PGArrayOf name arr ty :: Constraint where
562− PGArrayOf name ('PGvararray x) ty = x ~ ty
563− PGArrayOf name ('PGfixarray n x) ty = x ~ ty
564− PGArrayOf name val ty = TypeError
565− ( 'Text name :<>: 'Text "Unsatisfied PGArrayOf constraint. Expected either: "
566− :$$: 'Text " • " :<>: ErrPGvararrayOf ( 'ShowType ty )
567− :$$: 'Text " • " :<>: ErrPGfixarrayOf ( 'ShowType ty )
568− :$$: 'Text "But got: " :<>: 'ShowType val)
569−
570−-- | Ensure a type is a valid array type whose elements are text.
571−type PGTextArray name arr = PGArrayOf name arr ('NotNull 'PGtext)
572−
573295-- | `PGTypeOf` forgets about @NULL@ and any column constraints.
574296type family PGTypeOf (ty :: NullityType) :: PGType where
575297 PGTypeOf (nullity pg) = pg
@@ -583,14 +305,24 @@ instance ty0 ~ ty1 => SamePGType
583305
584306-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.
585307type 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
586314 AllNotNull '[] = ()
587− AllNotNull (column ::: def :=> 'NotNull ty ': columns) = AllNotNull columns
588315
589316-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some
590317-- @NOT NULL@.
591318type family NotAllNull (columns :: ColumnsType) :: Constraint where
592− NotAllNull (column ::: def :=> 'NotNull ty ': columns) = ()
593− NotAllNull (column ::: def :=> 'Null ty ': columns) = NotAllNull columns
319+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
320+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
321+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
322+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
323+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()
324+ NotAllNull (_ ::: _ :=> 'NotNull _ ': _) = ()
325+ NotAllNull (_ ::: _ :=> 'Null _ ': columns) = NotAllNull columns
594326
595327-- | `NullifyType` is an idempotent that nullifies a `NullityType`.
596328type family NullifyType (ty :: NullityType) :: NullityType where
@@ -599,33 +331,37 @@ type family NullifyType (ty :: NullityType) :: NullityType where
599331
600332-- | `NullifyRow` is an idempotent that nullifies a `RowType`.
601333type family NullifyRow (columns :: RowType) :: RowType where
602− NullifyRow '[] = '[]
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
603344 NullifyRow (column ::: ty ': columns) =
604345 column ::: NullifyType ty ': NullifyRow columns
346+ NullifyRow '[] = '[]
605347
606348-- | `NullifyFrom` is an idempotent that nullifies a `FromType`
607349-- used to nullify the left or right hand side of an outer join
608350-- in a `Squeal.PostgreSQL.Query.FromClause`.
609351type family NullifyFrom (tables :: FromType) :: FromType where
610− NullifyFrom '[] = '[]
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
611362 NullifyFrom (table ::: columns ': tables) =
612363 table ::: NullifyRow columns ': NullifyFrom tables
613−
614−-- | `Join` is simply promoted `++` and is used in @JOIN@s in
615−-- `Squeal.PostgreSQL.Query.FromClause`s.
616−type family Join xs ys where
617− Join '[] ys = ys
618− Join (x ': xs) ys = x ': Join xs ys
619−
620−-- | `disjoin` is a utility function for splitting an `NP` list into pieces.
621−disjoin
622− :: forall xs ys expr. SListI xs
623− => NP expr (Join xs ys)
624− -> (NP expr xs, NP expr ys)
625−disjoin = case sList @xs of
626− SNil -> \ys -> (Nil, ys)
627− SCons -> \(x :* xsys) ->
628− case disjoin xsys of (xs,ys) -> (x :* xs, ys)
364+ NullifyFrom '[] = '[]
629365
630366-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in
631367-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@
@@ -635,30 +371,101 @@ type family Create alias x xs where
635371 Create alias x (alias ::: y ': xs) = TypeError
636372 ('Text "Create: alias "
637373 ':<>: 'ShowType alias
638− ':<>: 'Text "already in use")
374+ ':<>: 'Text "already exists")
639375 Create alias y (x ': xs) = x ': Create alias y xs
640376
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+
641394-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@
642395-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements
643396-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.
644397type family Drop alias xs where
645− Drop alias ((alias ::: x) ': xs) = xs
398+ Drop alias '[] = TypeError
399+ ('Text "Drop: alias "
400+ ':<>: 'ShowType alias
401+ ':<>: 'Text " does not exist" )
402+ Drop alias (alias ::: x ': xs) = xs
646403 Drop alias (x ': xs) = x ': Drop alias xs
647404
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+
648437-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@
649438-- with the type @x@ and is used in `Squeal.PostgreSQL.Definition.alterTable`
650439-- and `Squeal.PostgreSQL.Definition.alterColumn`.
651440type family Alter alias x xs where
441+ Alter alias x '[] = TypeError
442+ ('Text "Alter: alias "
443+ ':<>: 'ShowType alias
444+ ':<>: 'Text " does not exist" )
652445 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs
653446 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs
654447
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
452+
655453-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@
656454-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and
657455-- `Squeal.PostgreSQL.Definition.renameColumn`.
658456type family Rename alias0 alias1 xs where
457+ Rename alias0 alias1 '[] = TypeError
458+ ('Text "Rename: alias "
459+ ':<>: 'ShowType alias0
460+ ':<>: 'Text " does not exist" )
659461 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs
660462 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs
661463
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
468+
662469-- | Check if a `TableConstraint` involves a column
663470type family ConstraintInvolves column constraint where
664471 ConstraintInvolves column ('Check columns) = column `Elem` columns
@@ -675,22 +482,35 @@ type family DropIfConstraintsInvolve column constraints where
675482 (DropIfConstraintsInvolve column constraints)
676483 (alias ::: constraint ': DropIfConstraintsInvolve column constraints)
677484
678−{- | Calculate the `Length` of a type level list
679−
680−>>> :kind! Length '[Char,String,Bool,Double]
681−Length '[Char,String,Bool,Double] :: Nat
682−= 4
683−-}
684−type family Length (xs :: [k]) :: Nat where
685− Length (x : xs) = 1 + Length xs
686− Length '[] = 0
687−
688485-- | A `SchemumType` is a user-defined type, either a `Table`,
689486-- `View` or `Typedef`.
690487data SchemumType
691488 = Table TableType
692489 | View RowType
693490 | 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
694514
695515{- | The schema of a database consists of a list of aliased,
696516user-defined `SchemumType`s.
@@ -733,9 +553,7 @@ There are several reasons why one might want to use schemas:
733553-}
734554type SchemasType = [(Symbol,SchemaType)]
735555
736−{-|
737−
738−-}
556+-- | A type family to use for a single schema database.
739557type family Public (schema :: SchemaType) :: SchemasType
740558 where Public schema = '["public" ::: schema]
741559
@@ -764,23 +582,15 @@ type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]
764582-- | Is a type a valid JSON type?
765583type PGJsonType = '[ 'PGjson, 'PGjsonb ]
766584
767−-- | An `AlignedList` is a type-aligned list or free category.
768−data AlignedList p x0 x1 where
769− Done :: AlignedList p x x
770− (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2
771−infixr 7 :>>
772−instance Category (AlignedList p) where
773− id = Done
774− (.) list = \case
775− Done -> list
776− step :>> steps -> step :>> (steps >>> list)
777−instance (forall t0 t1. RenderSQL (p t0 t1))
778− => RenderSQL (AlignedList p x0 x1) where
779− renderSQL = \case
780− Done -> ""
781− step :>> Done -> renderSQL step
782− step :>> steps -> renderSQL step <> ", " <> renderSQL steps
783−
784−-- | A `single` step.
785−single :: p x0 x1 -> AlignedList p x0 x1
786−single step = step :>> Done
585+-- | Utility class for `AllUnique` to provide nicer error messages.
586+class IsNotElem x isElem where
587+instance IsNotElem x 'False where
588+instance (TypeError ( 'Text "Cannot assign to "
589+ ':<>: 'ShowType alias
590+ ':<>: 'Text " more than once"))
591+ => IsNotElem '(alias, a) 'True where
592+
593+-- | No elem of @xs@ appears more than once, in the context of assignment.
594+class AllUnique (xs :: [(Symbol, a)]) where
595+instance AllUnique '[] where
596+instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where
squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+78−48
@@ -1,7 +1,7 @@
11{-|
22Module: Squeal.PostgreSQL.Transaction
33Description: Squeal transaction control language
4−Copyright: (c) Eitan Chatav, 2017
4+Copyright: (c) Eitan Chatav, 2019
55Maintainer: eitan@morphism.tech
66Stability: experimental
77
@@ -20,11 +20,12 @@ module Squeal.PostgreSQL.Transaction
2020 ( -- * Transaction
2121 transactionally
2222 , transactionally_
23+ , transactionallyRetry
24+ , ephemerally
25+ , ephemerally_
2326 , begin
2427 , commit
2528 , rollback
26− , transactionallySchema
27− , transactionallySchema_
2829 -- * Transaction Mode
2930 , TransactionMode (..)
3031 , defaultMode
@@ -34,70 +35,99 @@ module Squeal.PostgreSQL.Transaction
3435 , DeferrableMode (..)
3536 ) where
3637
37−import Control.Exception.Lifted
38−import Control.Monad.Base
39−import Control.Monad.Trans.Control
40−import Generics.SOP
41−
42−import qualified Database.PostgreSQL.LibPQ as LibPQ
38+import UnliftIO
4339
4440import Squeal.PostgreSQL.Manipulation
4541import Squeal.PostgreSQL.Render
4642import Squeal.PostgreSQL.PQ
47−import Squeal.PostgreSQL.Schema
4843
49−-- | Run a schema invariant computation `transactionally`.
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+-}
5050transactionally
51− :: (MonadBaseControl IO tx, MonadPQ schemas tx)
51+ :: (MonadUnliftIO tx, MonadPQ schemas tx)
5252 => TransactionMode
5353 -> tx x -- ^ run inside a transaction
5454 -> tx x
5555transactionally mode tx = mask $ \restore -> do
56− _ <- begin mode
57− result <- restore tx `onException` rollback
58− _ <- commit
56+ manipulate_ $ begin mode
57+ result <- restore tx `onException` (manipulate_ rollback)
58+ manipulate_ commit
5959 return result
6060
61−-- | Run a schema invariant computation `transactionally_` in `defaultMode`.
61+-- | Run a computation `transactionally_`, in `defaultMode`.
6262transactionally_
63− :: (MonadBaseControl IO tx, MonadPQ schemas tx)
63+ :: (MonadUnliftIO tx, MonadPQ schemas tx)
6464 => tx x -- ^ run inside a transaction
6565 -> tx x
6666transactionally_ = transactionally defaultMode
6767
68−-- | @BEGIN@ a transaction.
69−begin :: MonadPQ schemas tx => TransactionMode -> tx (K Result ('[] :: RowType))
70−begin mode = manipulate . UnsafeManipulation $
71− "BEGIN" <+> renderSQL mode <> ";"
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
72112
73−-- | @COMMIT@ a schema invariant transaction.
74−commit :: MonadPQ schemas tx => tx (K Result ('[] :: RowType))
75−commit = manipulate $ UnsafeManipulation "COMMIT;"
113+{- | Run a computation `ephemerally` in `defaultMode`. -}
114+ephemerally_
115+ :: (MonadUnliftIO tx, MonadPQ schemas tx)
116+ => tx x -- ^ run inside an ephemeral transaction
117+ -> tx x
118+ephemerally_ = ephemerally defaultMode
119+
120+-- | @BEGIN@ a transaction.
121+begin :: TransactionMode -> Manipulation_ schemas () ()
122+begin mode = UnsafeManipulation $ "BEGIN" <+> renderSQL mode
76123
77−-- | @ROLLBACK@ a schema invariant transaction.
78−rollback :: MonadPQ schemas tx => tx (K Result ('[] :: RowType))
79−rollback = manipulate $ UnsafeManipulation "ROLLBACK;"
124+-- | @COMMIT@ a transaction.
125+commit :: Manipulation_ schemas () ()
126+commit = UnsafeManipulation "COMMIT"
80127
81−-- | Run a schema changing computation `transactionallySchema`.
82−transactionallySchema
83− :: MonadBaseControl IO io
84− => TransactionMode
85− -> PQ schemas0 schemas1 io x
86− -> PQ schemas0 schemas1 io x
87−transactionallySchema mode u = PQ $ \ conn -> mask $ \ restore -> do
88− _ <- liftBase . LibPQ.exec (unK conn) $
89− "BEGIN" <+> renderSQL mode <> ";"
90− x <- restore (unPQ u conn)
91− `onException` (liftBase (LibPQ.exec (unK conn) "ROLLBACK"))
92− _ <- liftBase $ LibPQ.exec (unK conn) "COMMIT"
93− return x
94−
95−-- | Run a schema changing computation `transactionallySchema_` in `defaultMode`.
96−transactionallySchema_
97− :: MonadBaseControl IO io
98− => PQ schemas0 schemas1 io x
99− -> PQ schemas0 schemas1 io x
100−transactionallySchema_ = transactionallySchema defaultMode
128+-- | @ROLLBACK@ a transaction.
129+rollback :: Manipulation_ schemas () ()
130+rollback = UnsafeManipulation "ROLLBACK"
101131
102132-- | The available transaction characteristics are the transaction `IsolationLevel`,
103133-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.
@@ -110,7 +140,7 @@ data TransactionMode = TransactionMode
110140-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
111141-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.
112142defaultMode :: TransactionMode
113−defaultMode = TransactionMode Serializable ReadWrite NotDeferrable
143+defaultMode = TransactionMode ReadCommitted ReadWrite NotDeferrable
114144
115145-- | `TransactionMode` with a `Serializable` `IsolationLevel`,
116146-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.
squeal-postgresql/test/Doc.hsnew file+6
@@ -0,0 +1,6 @@
1+module Main (main) where
2+
3+import Test.DocTest
4+
5+main :: IO ()
6+main = doctest [ "-isrc", "src" ]
squeal-postgresql/test/DocTest.hsdeleted−18
@@ -1,18 +0,0 @@
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.hsnew file+166
@@ -0,0 +1,166 @@
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.hsnew file+136
@@ -0,0 +1,136 @@
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-postgresql/test/Specs/ExceptionHandling.hsdeleted−126
@@ -1,126 +0,0 @@
1−{-# LANGUAGE DataKinds #-}
2−{-# LANGUAGE DeriveGeneric #-}
3−{-# LANGUAGE DuplicateRecordFields #-}
4−{-# LANGUAGE FlexibleContexts #-}
5−{-# LANGUAGE OverloadedLabels #-}
6−{-# LANGUAGE OverloadedLists #-}
7−{-# LANGUAGE OverloadedStrings #-}
8−{-# LANGUAGE TypeApplications #-}
9−{-# LANGUAGE TypeFamilies #-}
10−{-# LANGUAGE TypeInType #-}
11−{-# LANGUAGE TypeOperators #-}
12−module ExceptionHandling
13− ( specs
14− , User (..)
15− )
16−where
17−
18−import Control.Monad (void)
19−import Control.Monad.Base (MonadBase)
20−import qualified Data.ByteString.Char8 as Char8
21−import Data.Int (Int16)
22−import Data.Text (Text)
23−import Data.Vector (Vector)
24−import qualified Generics.SOP as SOP
25−import qualified GHC.Generics as GHC
26−import Squeal.PostgreSQL
27−import Squeal.PostgreSQL.Migration
28−import Test.Hspec
29−
30−type Schema =
31− '[ "users" ::: 'Table (
32− '[ "pk_users" ::: 'PrimaryKey '["id"]
33− , "unique_names" ::: 'Unique '["name"]
34− ] :=>
35− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
36− , "name" ::: 'NoDef :=> 'NotNull 'PGtext
37− , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray ('Null 'PGint2))
38− ])
39− , "emails" ::: 'Table (
40− '[ "pk_emails" ::: 'PrimaryKey '["id"]
41− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
42− ] :=>
43− '[ "id" ::: 'Def :=> 'NotNull 'PGint4
44− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
45− , "email" ::: 'NoDef :=> 'Null 'PGtext
46− ])
47− ]
48−
49−type Schemas = Public Schema
50−
51−data User =
52− User { userName :: Text
53− , userEmail :: Maybe Text
54− , userVec :: VarArray (Vector (Maybe Int16)) }
55− deriving (Show, GHC.Generic)
56−instance SOP.Generic User
57−instance SOP.HasDatatypeInfo User
58−
59−insertUser :: Manipulation '[] Schemas '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]
60− '[ "fromOnly" ::: 'NotNull 'PGint4 ]
61−insertUser = insertInto #users
62− (Values_ (defaultAs #id :* param @1 `as` #name :* param @2 `as` #vec))
63− OnConflictDoRaise (Returning (#id `as` #fromOnly))
64−
65−setup :: Definition (Public '[]) Schemas
66−setup =
67− createTable #users
68− ( serial `as` #id :*
69− (text & notNullable) `as` #name :*
70− (vararray int2 & notNullable) `as` #vec )
71− ( primaryKey #id `as` #pk_users
72− :* unique #name `as` #unique_names )
73− >>>
74− createTable #emails
75− ( serial `as` #id :*
76− (int & notNullable) `as` #user_id :*
77− (text & nullable) `as` #email )
78− ( primaryKey #id `as` #pk_emails :*
79− foreignKey #user_id #users #id
80− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
81−
82−teardown :: Definition Schemas (Public '[])
83−teardown = dropTable #emails >>> dropTable #users
84−
85−migration :: Migration IO (Public '[]) Schemas
86−migration = Migration { name = "test"
87− , up = void $ define setup
88− , down = void $ define teardown }
89−
90−setupDB :: IO ()
91−setupDB = void . withConnection connectionString $
92− manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
93− & pqThen (migrateUp (single migration))
94−
95−dropDB :: IO ()
96−dropDB = void . withConnection connectionString $
97− manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")
98− & pqThen (migrateDown (single migration))
99−
100−connectionString :: Char8.ByteString
101−connectionString = "host=localhost port=5432 dbname=exampledb"
102−
103−testUser :: User
104−testUser = User "TestUser" Nothing (VarArray [])
105−
106−newUser :: (MonadBase IO m, MonadPQ Schemas m) => User -> m ()
107−newUser u = void $ manipulateParams insertUser (userName u, userVec u)
108−
109−insertUserTwice :: (MonadBase IO m, MonadPQ Schemas m) => m ()
110−insertUserTwice = newUser testUser >> newUser testUser
111−
112−specs :: SpecWith ()
113−specs = before_ setupDB $ after_ dropDB $
114− describe "Exceptions" $ do
115−
116− let
117− dupKeyErr = PQException FatalError (Just "23505")
118− (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")
119−
120− it "should be thrown for unique constraint violation in a manipulation" $
121− withConnection connectionString insertUserTwice
122− `shouldThrow` (== dupKeyErr)
123−
124− it "should be rethrown for unique constraint violation in a manipulation by a transaction" $
125− withConnection connectionString (transactionally_ insertUserTwice)
126− `shouldThrow` (== dupKeyErr)
squeal-postgresql/test/Specs/Specs.hsdeleted−7
@@ -1,7 +0,0 @@
1−module Specs where
2−
3−import Test.Hspec
4−import qualified ExceptionHandling
5−
6−main :: IO ()
7−main = hspec ExceptionHandling.specs
stack.yaml+6−1
@@ -1,3 +1,8 @@
1−resolver: lts-13.8
1+resolver: nightly-2019-07-14
22packages:
33- squeal-postgresql
4+
5+extra-deps:
6+- unliftio-pool-0.2.1.0
7+- github: morphismtech/free-categories
8+ commit: c0e555fbefb5c21619e532264c4dfeac556d0630