7622208 · squeal · git.iko.soy

git.iko.soy/squeal

Merge pull request #136 from morphismtech/dev

Squeal 0.5

commit7622208255bce1724d49b7b8094696a1ed3a39d6 authorEitan Chatav <eitan.chatav@gmail.com> dateTue 18 Jun 2019, 00:43 (7 years ago) parent07fd591 1d6caee

40 files changed+7050−4530

compare with dev

unifiedsplit

.circleci/config.yml+1−1

@@ -2,7 +2,7 @@ version: 2

22jobs:

33 build:

44 docker:

5− - image: haskell:8.4.3

5+ - image: haskell:8.6.3

66 - image: circleci/postgres:latest

77 environment:

88 POSTGRES_USER: root

README.md+65−76

@@ -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.

@@ -99,21 +101,21 @@ 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

@@ -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

185−we insert into the users table, we will need a parameter for the `name`

186−field but not for the `id` field. Since it's serial, we can use a default

183+We'll need a Haskell type for @User@s. We give the type `Generics.SOP.Generic` and

184+`Generics.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

196+we insert into the users table, we will need a parameter for the @name@

197+field 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

3+### Version 0.5

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.

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+27−33

@@ -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)

@@ -41,8 +40,10 @@ type Schema =

4140 ])

4241 ]

4342

44−setup :: Definition '[] Schema

45−setup =

43+type Schemas = Public Schema

44+

45+setup :: Definition (Public '[]) Schemas

46+setup =

4647 createTable #users

4748 ( serial `as` #id :*

4849 (text & notNullable) `as` #name :*

@@ -57,54 +58,47 @@ setup =

5758 foreignKey #user_id #users #id

5859 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

5960

60−teardown :: Definition Schema '[]

61+teardown :: Definition Schemas (Public '[])

6162teardown = dropTable #emails >>> dropTable #users

6263

63−insertUser :: Manipulation Schema '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]

64− '[ "fromOnly" ::: 'NotNull 'PGint4 ]

65−insertUser = insertRows #users

66− (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec) []

67− OnConflictDoNothing (Returning (#id `as` #fromOnly))

68−

69−insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

70−insertEmail = insertRows #emails

71− ( Default `as` #id :*

72− Set (param @1) `as` #user_id :*

73− Set (param @2) `as` #email ) []

74− OnConflictDoNothing (Returning Nil)

75−

76−getUsers :: Query Schema '[]

77− '[ "userName" ::: 'NotNull 'PGtext

78− , "userEmail" ::: 'Null 'PGtext

79− , "userVec" ::: 'NotNull ('PGvararray ('Null 'PGint2))]

80−getUsers = select

64+insertUser :: Manipulation_ Schemas (Text, VarArray (Vector (Maybe Int16))) (Only Int32)

65+insertUser = insertInto #users

66+ (Values_ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec))

67+ (OnConflict (OnConstraint #pk_users) DoNothing) (Returning_ (#id `as` #fromOnly))

68+

69+insertEmail :: Manipulation_ Schemas (Int32, Maybe Text) ()

70+insertEmail = insertInto_ #emails

71+ (Values_ (Default `as` #id :* Set (param @1) `as` #user_id :* Set (param @2) `as` #email))

72+

73+getUsers :: Query_ Schemas () User

74+getUsers = select_

8175 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail :* #u ! #vec `as` #userVec)

8276 ( from (table (#users `as` #u)

8377 & innerJoin (table (#emails `as` #e))

8478 (#u ! #id .== #e ! #user_id)) )

8579

86−data User = User { userName :: Text, userEmail :: Maybe Text, userVec :: Vector (Maybe Int16) }

80+data User = User { userName :: Text, userEmail :: Maybe Text, userVec :: VarArray (Vector (Maybe Int16)) }

8781 deriving (Show, GHC.Generic)

8882instance SOP.Generic User

8983instance SOP.HasDatatypeInfo User

9084

9185users :: [User]

92−users =

93− [ User "Alice" (Just "alice@gmail.com") [Nothing, Just 1]

94− , User "Bob" Nothing [Just 2, Nothing]

95− , User "Carole" (Just "carole@hotmail.com") [Just 3]

86+users =

87+ [ User "Alice" (Just "alice@gmail.com") (VarArray [Nothing, Just 1])

88+ , User "Bob" Nothing (VarArray [Just 2, Nothing])

89+ , User "Carole" (Just "carole@hotmail.com") (VarArray [Just 3])

9690 ]

9791

98−session :: (MonadBase IO pq, MonadPQ Schema pq) => pq ()

92+session :: (MonadIO pq, MonadPQ Schemas pq) => pq ()

9993session = do

100− liftBase $ Char8.putStrLn "manipulating"

94+ liftIO $ Char8.putStrLn "manipulating"

10195 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])

10296 ids <- traverse (fmap fromOnly . getRow 0) idResults

10397 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))

104− liftBase $ Char8.putStrLn "querying"

98+ liftIO $ Char8.putStrLn "querying"

10599 usersResult <- runQuery getUsers

106100 usersRows <- getRows usersResult

107− liftBase $ print (usersRows :: [User])

101+ liftIO $ print (usersRows :: [User])

108102

109103main :: IO ()

110104main = do

@@ -122,7 +116,7 @@ main = do

122116

123117main2 :: IO ()

124118main2 =

125− void . withConnection "host=localhost port=5432 dbname=exampledb" $

119+ withConnection "host=localhost port=5432 dbname=exampledb" $

126120 define setup

127121 & pqThen session

128122 & pqThen (define teardown)

squeal-postgresql/squeal-postgresql.cabal+24−7

@@ -1,5 +1,5 @@

11name: squeal-postgresql

2−version: 0.4.0.0

2+version: 0.5.0.0

33synopsis: Squeal PostgreSQL Library

44description: Squeal is a type-safe embedding of PostgreSQL in Haskell

55homepage: https://github.com/morphismtech/squeal

@@ -22,19 +22,39 @@ library

2222 hs-source-dirs: src

2323 exposed-modules:

2424 Squeal.PostgreSQL

25+ Squeal.PostgreSQL.Alias

2526 Squeal.PostgreSQL.Binary

2627 Squeal.PostgreSQL.Definition

2728 Squeal.PostgreSQL.Expression

29+ Squeal.PostgreSQL.Expression.Aggregate

30+ Squeal.PostgreSQL.Expression.Collection

31+ Squeal.PostgreSQL.Expression.Comparison

32+ Squeal.PostgreSQL.Expression.Json

33+ Squeal.PostgreSQL.Expression.Literal

34+ Squeal.PostgreSQL.Expression.Logic

35+ Squeal.PostgreSQL.Expression.Math

36+ Squeal.PostgreSQL.Expression.Null

37+ Squeal.PostgreSQL.Expression.Parameter

38+ Squeal.PostgreSQL.Expression.SetOf

39+ Squeal.PostgreSQL.Expression.Sort

40+ Squeal.PostgreSQL.Expression.Subquery

41+ Squeal.PostgreSQL.Expression.Text

42+ Squeal.PostgreSQL.Expression.TextSearch

43+ Squeal.PostgreSQL.Expression.Time

44+ Squeal.PostgreSQL.Expression.Type

45+ Squeal.PostgreSQL.Expression.Window

46+ Squeal.PostgreSQL.List

2847 Squeal.PostgreSQL.Manipulation

2948 Squeal.PostgreSQL.Migration

3049 Squeal.PostgreSQL.Pool

50+ Squeal.PostgreSQL.PG

3151 Squeal.PostgreSQL.PQ

3252 Squeal.PostgreSQL.Render

3353 Squeal.PostgreSQL.Query

3454 Squeal.PostgreSQL.Schema

3555 Squeal.PostgreSQL.Transaction

3656 default-language: Haskell2010

37− ghc-options: -Wall

57+ ghc-options: -Wall -Werror

3858 build-depends:

3959 aeson >= 1.2.4.0

4060 , base >= 4.11.1.0 && < 5.0

@@ -43,9 +63,7 @@ library

4363 , bytestring-strict-builder >= 0.4.5

4464 , deepseq >= 1.4.3.0

4565 , generics-sop >= 0.3.2.0

46− , lifted-base >= 0.2.3.12

4766 , mmorph >= 1.1.1

48− , monad-control >= 1.0.2.3

4967 , mtl >= 2.2.2

5068 , network-ip >= 0.3.0.2

5169 , postgresql-binary >= 0.12.1

@@ -56,7 +74,8 @@ library

5674 , text >= 1.2.3.0

5775 , time >= 1.8.0.2

5876 , transformers >= 0.5.2.0

59− , transformers-base >= 0.4.4

77+ , unliftio >= 0.2.10

78+ , unliftio-pool >= 0.2.1.0

6079 , uuid-types >= 1.0.3

6180 , vector >= 0.12.0.1

6281

@@ -85,7 +104,6 @@ test-suite squeal-postgresql-specs

85104 , squeal-postgresql

86105 , text >= 1.2.2.2

87106 , transformers >= 0.5.2.0

88− , transformers-base >= 0.4.4

89107 , vector >= 0.12.0.1

90108

91109executable squeal-postgresql-example

@@ -101,5 +119,4 @@ executable squeal-postgresql-example

101119 , squeal-postgresql

102120 , text >= 1.2.2.2

103121 , transformers >= 0.5.2.0

104− , transformers-base >= 0.4.4

105122 , vector >= 0.12.0.1

squeal-postgresql/src/Squeal/PostgreSQL.hs+92−95

@@ -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

@@ -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

15−>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators

16−

14+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels -XFlexibleContexts

15+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators -XGADTs

16+

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

@@ -32,26 +30,26 @@ The first step is to define the schema of our database. This is where

3230we use @DataKinds@ and @TypeOperators@.

3331

3432>>> :{

33+type UsersColumns =

34+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4

35+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext ]

36+type UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]

37+type EmailsColumns =

38+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4

39+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

40+ , "email" ::: 'NoDef :=> 'Null 'PGtext ]

41+type EmailsConstraints =

42+ '[ "pk_emails" ::: 'PrimaryKey '["id"]

43+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"] ]

3544type Schema =

36− '[ "users" ::: 'Table (

37− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

38− '[ "id" ::: 'Def :=> 'NotNull 'PGint4

39− , "name" ::: 'NoDef :=> 'NotNull 'PGtext

40− ])

41− , "emails" ::: 'Table (

42− '[ "pk_emails" ::: 'PrimaryKey '["id"]

43− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]

44− ] :=>

45− '[ "id" ::: 'Def :=> 'NotNull 'PGint4

46− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

47− , "email" ::: 'NoDef :=> 'Null 'PGtext

48− ])

49− ]

45+ '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)

46+ , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]

47+type Schemas = Public Schema

5048:}

5149

5250Notice the use of type operators.

5351

54−`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemumType`,

52+`:::` is used to pair an alias `GHC.TypeLits.Symbol` with a `SchemasType`, a `SchemumType`,

5553a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's @::@

5654operator.

5755

@@ -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

@@ -68,8 +66,8 @@ labels to refer to named tables and columns in our schema.

6866

6967>>> :{

7068let

71− setup :: Definition '[] Schema

72− setup =

69+ setup :: Definition (Public '[]) Schemas

70+ setup =

7371 createTable #users

7472 ( serial `as` #id :*

7573 (text & notNullable) `as` #name )

@@ -89,14 +87,14 @@ We can easily see the generated SQL is unsurprising looking.

8987CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));

9088CREATE 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);

9189

92−Notice that @setup@ starts with an empty schema @'[]@ and produces @Schema@.

90+Notice that @setup@ starts with an empty public schema @(Public '[])@ and produces @Schemas@.

9391In our `createTable` commands we included `TableConstraint`s to define

9492primary and foreign keys, making them somewhat complex. Our @teardown@

9593`Definition` is simpler.

9694

9795>>> :{

9896let

99− teardown :: Definition Schema '[]

97+ teardown :: Definition Schemas (Public '[])

10098 teardown = dropTable #emails >>> dropTable #users

10199:}

102100

@@ -104,51 +102,49 @@ 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 `insertRow`, `update` or `deleteFrom`

109−has three type parameters, the schema it refers to, a list of parameters

110−it can take as input, and a list of columns it produces as output. When

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−>>> :{

119−let

120− insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]

121− insertUser = insertRow #users

122− (Default `as` #id :* Set (param @1) `as` #name)

123− OnConflictDoNothing (Returning (#id `as` #fromOnly))

124−:}

120+the emails table. We can do this in a single `Manipulation_` by using a

121+`with` statement.

125122

126123>>> :{

127124let

128− insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

129− insertEmail = insertRow #emails

130− ( Default `as` #id :*

131− Set (param @1) `as` #user_id :*

132− Set (param @2) `as` #email )

133− OnConflictDoNothing (Returning Nil)

125+ insertUser :: Manipulation_ Schemas User ()

126+ insertUser = with (u `as` #u) e

127+ where

128+ u = insertInto #users

129+ (Values_ (Default `as` #id :* Set (param @1) `as` #name))

130+ OnConflictDoRaise (Returning_ (#id :* param @2 `as` #email))

131+ e = insertInto_ #emails $ Select

132+ (Default `as` #id :* Set (#u ! #id) `as` #user_id :* Set (#u ! #email) `as` #email)

133+ (from (common #u))

134134:}

135135

136136>>> printSQL insertUser

137−INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) ON CONFLICT DO NOTHING RETURNING "id" AS "fromOnly"

138−>>> printSQL insertEmail

139−INSERT INTO "emails" ("id", "user_id", "email") VALUES (DEFAULT, ($1 :: int4), ($2 :: text)) ON CONFLICT DO NOTHING

137+WITH "u" AS (INSERT INTO "users" ("id", "name") VALUES (DEFAULT, ($1 :: text)) RETURNING "id" AS "id", ($2 :: text) AS "email") INSERT INTO "emails" ("user_id", "email") SELECT "u"."id", "u"."email" FROM "u" AS "u"

140138

141−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

142140interested in the ids here, just the usernames and email addresses. We

143−need to use an inner join to get the right result. A `Query` is like a

144−`Manipulation` with the same kind of type parameters.

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.

145143

146144>>> :{

147145let

148− getUsers :: Query Schema '[]

149− '[ "userName" ::: 'NotNull 'PGtext

150− , "userEmail" ::: 'Null 'PGtext ]

151− getUsers = select

146+ getUsers :: Query_ Schemas () User

147+ getUsers = select_

152148 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)

153149 ( from (table (#users `as` #u)

154150 & innerJoin (table (#emails `as` #e))

@@ -158,22 +154,12 @@ let

158154>>> printSQL getUsers

159155SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")

160156

161−Now that we've defined the SQL side of things, we'll need a Haskell type

162−for users. We give the type `Generics.SOP.Generic` and

163−`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows

164−we receive when we run @getUsers@. Notice that the record fields of the

165−@User@ type match the column names of @getUsers@.

166−

167−>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)

168−>>> instance SOP.Generic User

169−>>> instance SOP.HasDatatypeInfo User

170−

171−Let's also create some users to add to the database.

157+Let's create some users to add to the database.

172158

173159>>> :{

174160let

175161 users :: [User]

176− users =

162+ users =

177163 [ User "Alice" (Just "alice@gmail.com")

178164 , User "Bob" Nothing

179165 , User "Carole" (Just "carole@hotmail.com")

@@ -190,38 +176,49 @@ transformer and when the schema doesn't change we can use `Monad` and

190176

191177>>> :{

192178let

193− session :: PQ Schema Schema IO ()

179+ session :: PQ Schemas Schemas IO ()

194180 session = do

195− idResults <- traversePrepared insertUser (Only . userName <$> users)

196− ids <- traverse (fmap fromOnly . getRow 0) idResults

197− traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))

181+ _ <- traversePrepared_ insertUser users

198182 usersResult <- runQuery getUsers

199183 usersRows <- getRows usersResult

200− liftBase $ print (usersRows :: [User])

184+ liftIO $ print (usersRows :: [User])

201185in

202− void . withConnection "host=localhost port=5432 dbname=exampledb" $

186+ withConnection "host=localhost port=5432 dbname=exampledb" $

203187 define setup

204188 & pqThen session

205189 & pqThen (define teardown)

206190:}

207191[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]

208192-}

209−module Squeal.PostgreSQL

210− ( module Squeal.PostgreSQL.Binary

211− , module Squeal.PostgreSQL.Definition

212− , module Squeal.PostgreSQL.Expression

213− , module Squeal.PostgreSQL.Manipulation

214− , module Squeal.PostgreSQL.PQ

215− , module Squeal.PostgreSQL.Query

216− , module Squeal.PostgreSQL.Schema

217− , module Squeal.PostgreSQL.Transaction

218− ) where

219−

220−import Squeal.PostgreSQL.Binary

221−import Squeal.PostgreSQL.Definition

222−import Squeal.PostgreSQL.Expression

223−import Squeal.PostgreSQL.Manipulation

224−import Squeal.PostgreSQL.PQ

225−import Squeal.PostgreSQL.Query

226−import Squeal.PostgreSQL.Schema

227−import Squeal.PostgreSQL.Transaction

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.Expression as X

199+import Squeal.PostgreSQL.Expression.Aggregate as X

200+import Squeal.PostgreSQL.Expression.Collection as X

201+import Squeal.PostgreSQL.Expression.Comparison as X

202+import Squeal.PostgreSQL.Expression.Json as X

203+import Squeal.PostgreSQL.Expression.Literal as X

204+import Squeal.PostgreSQL.Expression.Logic as X

205+import Squeal.PostgreSQL.Expression.Math as X

206+import Squeal.PostgreSQL.Expression.Null as X

207+import Squeal.PostgreSQL.Expression.Parameter as X

208+import Squeal.PostgreSQL.Expression.SetOf as X

209+import Squeal.PostgreSQL.Expression.Sort as X

210+import Squeal.PostgreSQL.Expression.Subquery as X

211+import Squeal.PostgreSQL.Expression.Text as X

212+import Squeal.PostgreSQL.Expression.TextSearch as X

213+import Squeal.PostgreSQL.Expression.Time as X

214+import Squeal.PostgreSQL.Expression.Type as X

215+import Squeal.PostgreSQL.Expression.Window as X

216+import Squeal.PostgreSQL.List as X

217+import Squeal.PostgreSQL.Manipulation as X

218+import Squeal.PostgreSQL.Migration as X

219+import Squeal.PostgreSQL.PG as X

220+import Squeal.PostgreSQL.PQ as X

221+import Squeal.PostgreSQL.Query as X

222+import Squeal.PostgreSQL.Render (RenderSQL(..), printSQL)

223+import Squeal.PostgreSQL.Schema as X

224+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

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+210−115

@@ -7,7 +7,7 @@ Stability: experimental

88This module provides binary encoding and decoding between Haskell and PostgreSQL types.

10−Instances are governed by the `Generic` and `HasDatatypeInfo` typeclasses, so you absolutely

10+Instances are governed by the `SOP.Generic` and `SOP.HasDatatypeInfo` typeclasses, so you absolutely

1111do not need to define your own instances to decode retrieved rows into Haskell values or

1212to encode Haskell values into statement parameters.

1313

@@ -16,10 +16,10 @@ 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

22−Define a Haskell datatype `Row` that will serve as both the input and output of a simple

22+Define a Haskell datatype @Row@ that will serve as both the input and output of a simple

2323round trip query.

2424

2525>>> data Row = Row { col1 :: Int16, col2 :: Text, col3 :: Maybe Bool } deriving (Eq, GHC.Generic)

@@ -27,7 +27,7 @@ round trip query.

2727>>> instance HasDatatypeInfo Row

2828>>> :{

2929let

30− roundTrip :: Query '[] (TuplePG Row) (RowPG Row)

30+ roundTrip :: Query_ (Public '[]) Row Row

3131 roundTrip = values_ $

3232 parameter @1 int2 `as` #col1 :*

3333 parameter @2 text `as` #col2 :*

@@ -39,15 +39,15 @@ 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

4949In addition to being able to encode and decode basic Haskell types

50−like `Int16` and `Text`, Squeal permits you to encode and decode Haskell types to

50+like `Int16` and `Data.Text.Text`, Squeal permits you to encode and decode Haskell types to

5151Postgres array, enumerated and composite types and json. Let's see another example,

5252this time using the `Vector` type which corresponds to variable length arrays

5353and homogeneous tuples which correspond to fixed length arrays. We can even

@@ -55,9 +55,9 @@ create multi-dimensional fixed length arrays.

5555

5656>>> :{

5757data Row = Row

58− { col1 :: Vector Int16

59− , col2 :: (Maybe Int16,Maybe Int16)

60− , col3 :: ((Int16,Int16),(Int16,Int16),(Int16,Int16))

58+ { col1 :: VarArray (Vector Int16)

59+ , col2 :: FixArray (Maybe Int16,Maybe Int16)

60+ , col3 :: FixArray ((Int16,Int16),(Int16,Int16),(Int16,Int16))

6161 } deriving (Eq, GHC.Generic)

6262:}

6363

@@ -68,20 +68,20 @@ Once again, we define a simple round trip query.

6868

6969>>> :{

7070let

71− roundTrip :: Query '[] (TuplePG Row) (RowPG Row)

71+ roundTrip :: Query_ (Public '[]) Row Row

7272 roundTrip = values_ $

73− parameter @1 (int2 & vararray) `as` #col1 :*

74− parameter @2 (int2 & fixarray @2) `as` #col2 :*

75− parameter @3 (int2 & fixarray @2 & fixarray @3) `as` #col3

73+ parameter @1 (int2 & vararray) `as` #col1 :*

74+ parameter @2 (int2 & fixarray @'[2]) `as` #col2 :*

75+ parameter @3 (int2 & fixarray @'[3,2]) `as` #col3

7676:}

7777

7878>>> :set -XOverloadedLists

79−>>> let input = Row [1,2] (Just 1,Nothing) ((1,2),(3,4),(5,6))

79+>>> 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

@@ -114,15 +114,15 @@ type Schema =

114114

115115>>> :{

116116let

117− setup :: Definition '[] Schema

117+ setup :: Definition (Public '[]) (Public Schema)

118118 setup =

119119 createTypeEnumFrom @Schwarma #schwarma >>>

120120 createTypeCompositeFrom @Person #person

121121:}

122122

123−Let's demonstrate how to associate our Haskell types `Schwarma` and `Person`

123+Let's demonstrate how to associate our Haskell types @Schwarma@ and @Person@

124124with enumerated, composite or json types in Postgres. First create a Haskell

125−`Row` type using the `Enumerated`, `Composite` and `Json` newtypes as fields.

125+@Row@ type using the `Enumerated`, `Composite` and `Json` newtypes as fields.

126126

127127>>> :{

128128data Row = Row

@@ -146,7 +146,7 @@ Once again, define a round trip query.

146146

147147>>> :{

148148let

149− roundTrip :: Query Schema (TuplePG Row) (RowPG Row)

149+ roundTrip :: Query_ (Public Schema) Row Row

150150 roundTrip = values_ $

151151 parameter @1 (typedef #schwarma) `as` #schwarma :*

152152 parameter @2 (typedef #person) `as` #person1 :*

@@ -157,7 +157,7 @@ Finally, we can drop our type definitions.

157157

158158>>> :{

159159let

160− teardown :: Definition Schema '[]

160+ teardown :: Definition (Public Schema) (Public '[])

161161 teardown = dropType #schwarma >>> dropType #person

162162:}

163163

@@ -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)

@@ -194,20 +194,30 @@ True

194194 , MultiParamTypeClasses

195195 , ScopedTypeVariables

196196 , TypeApplications

197+ , TypeFamilies

197198 , TypeInType

198199 , TypeOperators

199200 , UndecidableInstances

201+ , UndecidableSuperClasses

200202#-}

201203

202204module Squeal.PostgreSQL.Binary

203205 ( -- * Encoding

204206 ToParam (..)

205207 , ToParams (..)

208+ , ToNullityParam (..)

209+ , ToField (..)

210+ , ToFixArray (..)

206211 -- * Decoding

207212 , FromValue (..)

208213 , FromRow (..)

214+ , FromField (..)

215+ , FromFixArray (..)

209216 -- * Only

210217 , Only (..)

218+ -- * Oid

219+ , HasOid (..)

220+ , HasAliasedOid (..)

211221 ) where

212222

213223import BinaryParser

@@ -238,6 +248,9 @@ import qualified GHC.Generics as GHC

238248import qualified PostgreSQL.Binary.Decoding as Decoding

239249import qualified PostgreSQL.Binary.Encoding as Encoding

240250

251+import Squeal.PostgreSQL.Alias

252+import Squeal.PostgreSQL.List

253+import Squeal.PostgreSQL.PG

241254import Squeal.PostgreSQL.Schema

242255

243256-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into

@@ -269,6 +282,7 @@ instance ToParam Word64 'PGint8 where toParam = K . Encoding.int8_word64

269282instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4

270283instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8

271284instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric

285+instance ToParam Money 'PGmoney where toParam = K . Encoding.int8_int64 . cents

272286instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid

273287instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet

274288instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8

@@ -297,16 +311,25 @@ instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where

297311instance Aeson.ToJSON x => ToParam (Jsonb x) 'PGjsonb where

298312 toParam = K . Encoding.jsonb_bytes

299313 . Lazy.ByteString.toStrict . Aeson.encode . getJsonb

300−instance ToArray x ('NotNull ('PGvararray ty))

301− => ToParam x ('PGvararray ty) where

302− toParam

303− = K . Encoding.array (baseOid @x @('NotNull ('PGvararray ty)))

304− . unK . toArray @x @('NotNull ('PGvararray ty))

305−instance ToArray x ('NotNull ('PGfixarray n ty))

306− => ToParam x ('PGfixarray n ty) where

307− toParam

308− = K . Encoding.array (baseOid @x @('NotNull ('PGfixarray n ty)))

309− . unK . toArray @x @('NotNull ('PGfixarray n ty))

314+instance (ToNullityParam x ty, ty ~ nullity pg, HasOid pg)

315+ => ToParam (VarArray [x]) ('PGvararray ty) where

316+ toParam = K

317+ . Encoding.array_foldable (oid @pg) (unK . toNullityParam @x @ty)

318+ . getVarArray

319+instance (ToParam x pg, HasOid pg)

320+ => ToParam (VarArray (Vector x)) ('PGvararray ('NotNull pg)) where

321+ toParam = K

322+ . Encoding.array_vector (oid @pg) (unK . toParam @x @pg)

323+ . getVarArray

324+instance (ToParam x pg, HasOid pg)

325+ => ToParam (VarArray (Vector (Maybe x))) ('PGvararray ('Null pg)) where

326+ toParam = K

327+ . Encoding.nullableArray_vector (oid @pg) (unK . toParam @x @pg)

328+ . getVarArray

329+instance (ToFixArray x dims ty, ty ~ nullity pg, HasOid pg)

330+ => ToParam (FixArray x) ('PGfixarray dims ty) where

331+ toParam = K . Encoding.array (oid @pg)

332+ . unK . unK . toFixArray @x @dims @ty . getFixArray

310333instance

311334 ( IsEnumType x

312335 , HasDatatypeInfo x

@@ -371,11 +394,42 @@ instance

371394 in

372395 composite . encoders . toRecord . getComposite

373396

397+-- | The object identifier of a `PGType`.

398+--

399+-- >>> :set -XTypeApplications

400+-- >>> oid @'PGbool

401+-- 16

402+class HasOid (ty :: PGType) where oid :: Word32

403+instance HasOid 'PGbool where oid = 16

404+instance HasOid 'PGint2 where oid = 21

405+instance HasOid 'PGint4 where oid = 23

406+instance HasOid 'PGint8 where oid = 20

407+instance HasOid 'PGnumeric where oid = 1700

408+instance HasOid 'PGfloat4 where oid = 700

409+instance HasOid 'PGfloat8 where oid = 701

410+instance HasOid ('PGchar n) where oid = 18

411+instance HasOid ('PGvarchar n) where oid = 1043

412+instance HasOid 'PGtext where oid = 25

413+instance HasOid 'PGbytea where oid = 17

414+instance HasOid 'PGtimestamp where oid = 1114

415+instance HasOid 'PGtimestamptz where oid = 1184

416+instance HasOid 'PGdate where oid = 1082

417+instance HasOid 'PGtime where oid = 1083

418+instance HasOid 'PGtimetz where oid = 1266

419+instance HasOid 'PGinterval where oid = 1186

420+instance HasOid 'PGuuid where oid = 2950

421+instance HasOid 'PGinet where oid = 869

422+instance HasOid 'PGjson where oid = 114

423+instance HasOid 'PGjsonb where oid = 3802

424+

425+-- | Lifts a `HasOid` constraint to a field.

374426class HasAliasedOid (field :: (Symbol, NullityType)) where

375427 aliasedOid :: Word32

376428instance HasOid ty => HasAliasedOid (alias ::: nullity ty) where

377429 aliasedOid = oid @ty

378430

431+-- | A `ToNullityParam` constraint gives an encoding of a Haskell `Type` into

432+-- into the binary format of a PostgreSQL `NullityType`.

379433class ToNullityParam (x :: Type) (ty :: NullityType) where

380434 toNullityParam :: x -> K (Maybe Encoding.Encoding) ty

381435instance ToParam x pg => ToNullityParam x ('NotNull pg) where

@@ -383,55 +437,36 @@ instance ToParam x pg => ToNullityParam x ('NotNull pg) where

383437instance ToParam x pg => ToNullityParam (Maybe x) ('Null pg) where

384438 toNullityParam = K . fmap (unK . toParam @x @pg)

385439

440+-- | A `ToField` constraint lifts the `ToParam` parser

441+-- to an encoding of a @(Symbol, Type)@ to a @(Symbol, NullityType)@,

442+-- encoding `Null`s to `Maybe`s. You should not define instances for

443+-- `FromField`, just use the provided instances.

386444class ToField (x :: (Symbol, Type)) (field :: (Symbol, NullityType)) where

387445 toField :: P x -> K (Maybe Encoding.Encoding) field

388446instance ToNullityParam x ty => ToField (alias ::: x) (alias ::: ty) where

389447 toField (P x) = K . unK $ toNullityParam @x @ty x

390448

391−class ToArray (x :: Type) (array :: NullityType) where

392− toArray :: x -> K Encoding.Array array

393− baseOid :: Word32

394− default baseOid :: HasOid (PGTypeOf array) => Word32

395− baseOid = oid @(PGTypeOf array)

396−instance {-# OVERLAPPABLE #-} (HasOid pg, ToParam x pg)

397− => ToArray x ('NotNull pg) where

398− toArray = K . Encoding.encodingArray . unK . toParam @x @pg

399−instance {-# OVERLAPPABLE #-} (HasOid pg, ToParam x pg)

400− => ToArray (Maybe x) ('Null pg) where

401− toArray = K . maybe Encoding.nullArray

402− (Encoding.encodingArray . unK . toParam @x @pg)

403−instance {-# OVERLAPPING #-} ToArray x array

404− => ToArray (Vector x) ('NotNull ('PGvararray array)) where

405− toArray = K . Encoding.dimensionArray Vector.foldl'

406− (unK . toArray @x @array)

407− baseOid = baseOid @x @array

408−instance {-# OVERLAPPING #-} ToArray x array

409− => ToArray (Maybe (Vector x)) ('Null ('PGvararray array)) where

410− toArray = K . maybe Encoding.nullArray

411− (Encoding.dimensionArray Vector.foldl' (unK . toArray @x @array))

412− baseOid = baseOid @x @array

413−instance {-# OVERLAPPING #-}

414− ( IsProductType product xs

415− , Length xs ~ n

416− , All ((~) x) xs

417− , ToArray x array )

418− => ToArray product ('NotNull ('PGfixarray n array)) where

419− toArray = K . Encoding.dimensionArray foldlN

420− (unK . toArray @x @array) . unZ . unSOP . from

421− baseOid = baseOid @x @array

422−instance {-# OVERLAPPING #-}

449+-- | A `ToFixArray` constraint gives an encoding of a Haskell `Type`

450+-- into the binary format of a PostgreSQL fixed-length array.

451+-- You should not define instances for

452+-- `ToFixArray`, just use the provided instances.

453+class ToFixArray (x :: Type) (dims :: [Nat]) (array :: NullityType) where

454+ toFixArray :: x -> K (K Encoding.Array dims) array

455+instance ToNullityParam x ty => ToFixArray x '[] ty where

456+ toFixArray = K . K . maybe Encoding.nullArray Encoding.encodingArray . unK

457+ . toNullityParam @x @ty

458+instance

423459 ( IsProductType product xs

424− , Length xs ~ n

460+ , Length xs ~ dim

425461 , All ((~) x) xs

426− , ToArray x array )

427− => ToArray (Maybe product) ('Null ('PGfixarray n array)) where

428− toArray = K . maybe Encoding.nullArray

429− (Encoding.dimensionArray foldlN (unK . toArray @x @array) . unZ . unSOP . from)

430− baseOid = baseOid @x @array

462+ , ToFixArray x dims ty )

463+ => ToFixArray product (dim ': dims) ty where

464+ toFixArray = K . K . Encoding.dimensionArray foldlN

465+ (unK . unK . toFixArray @x @dims @ty) . unZ . unSOP . from

431466

432467-- | A `ToParams` constraint generically sequences the encodings of `Type`s

433468-- of the fields of a tuple or record to a row of `ColumnType`s. You should

434−-- not define instances of `ToParams`. Instead define `Generic` instances

469+-- not define instances of `ToParams`. Instead define `SOP.Generic` instances

435470-- which in turn provide `ToParams` instances.

436471class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where

437472 -- | >>> type Params = '[ 'NotNull 'PGbool, 'Null 'PGint2]

@@ -463,6 +498,7 @@ instance FromValue 'PGint8 Int64 where fromValue = Decoding.int

463498instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4

464499instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8

465500instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric

501+instance FromValue 'PGmoney Money where fromValue = Money <$> Decoding.int

466502instance FromValue 'PGuuid UUID where fromValue = Decoding.uuid

467503instance FromValue 'PGinet (NetAddr IP) where fromValue = Decoding.inet

468504instance FromValue ('PGchar 1) Char where fromValue = Decoding.char

@@ -492,12 +528,41 @@ instance Aeson.FromJSON x => FromValue 'PGjson (Json x) where

492528instance Aeson.FromJSON x => FromValue 'PGjsonb (Jsonb x) where

493529 fromValue = Jsonb <$>

494530 Decoding.jsonb_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)

495−instance FromArray ('NotNull ('PGvararray ty)) y

496− => FromValue ('PGvararray ty) y where

497− fromValue = Decoding.array (fromArray @('NotNull ('PGvararray ty)) @y)

498−instance FromArray ('NotNull ('PGfixarray n ty)) y

499− => FromValue ('PGfixarray n ty) y where

500− fromValue = Decoding.array (fromArray @('NotNull ('PGfixarray n ty)) @y)

531+instance FromValue pg y

532+ => FromValue ('PGvararray ('NotNull pg)) (VarArray (Vector y)) where

533+ fromValue =

534+ let

535+ rep n x = VarArray <$> Vector.replicateM n x

536+ in

537+ Decoding.array $ Decoding.dimensionArray rep

538+ (fromFixArray @'[] @('NotNull pg))

539+instance FromValue pg y

540+ => FromValue ('PGvararray ('Null pg)) (VarArray (Vector (Maybe y))) where

541+ fromValue =

542+ let

543+ rep n x = VarArray <$> Vector.replicateM n x

544+ in

545+ Decoding.array $ Decoding.dimensionArray rep

546+ (fromFixArray @'[] @('Null pg))

547+instance FromValue pg y

548+ => FromValue ('PGvararray ('NotNull pg)) (VarArray [y]) where

549+ fromValue =

550+ let

551+ rep n x = VarArray <$> replicateM n x

552+ in

553+ Decoding.array $ Decoding.dimensionArray rep

554+ (fromFixArray @'[] @('NotNull pg))

555+instance FromValue pg y

556+ => FromValue ('PGvararray ('Null pg)) (VarArray [Maybe y]) where

557+ fromValue =

558+ let

559+ rep n x = VarArray <$> replicateM n x

560+ in

561+ Decoding.array $ Decoding.dimensionArray rep

562+ (fromFixArray @'[] @('Null pg))

563+instance FromFixArray dims ty y

564+ => FromValue ('PGfixarray dims ty) (FixArray y) where

565+ fromValue = FixArray <$> Decoding.array (fromFixArray @dims @ty @y)

501566instance

502567 ( IsEnumType y

503568 , HasDatatypeInfo y

@@ -568,49 +633,32 @@ instance FromValue pg y

568633 K (Just bytestring) -> P . Just <$>

569634 Decoding.valueParser (fromValue @pg) bytestring

570635

571−class FromArray (ty :: NullityType) (y :: Type) where

572− fromArray :: Decoding.Array y

573−instance {-# OVERLAPPABLE #-} FromValue pg y

574− => FromArray ('NotNull pg) y where

575− fromArray = Decoding.valueArray (fromValue @pg @y)

576−instance {-# OVERLAPPABLE #-} FromValue pg y

577− => FromArray ('Null pg) (Maybe y) where

578− fromArray = Decoding.nullableValueArray (fromValue @pg @y)

579−instance {-# OVERLAPPING #-} FromArray array y

580− => FromArray ('NotNull ('PGvararray array)) (Vector y) where

581− fromArray =

582− Decoding.dimensionArray Vector.replicateM (fromArray @array @y)

583−instance {-# OVERLAPPING #-} FromArray array y

584− => FromArray ('Null ('PGvararray array)) (Maybe (Vector y)) where

585− fromArray = Just <$>

586− Decoding.dimensionArray Vector.replicateM (fromArray @array @y)

587−instance {-# OVERLAPPING #-}

588− ( FromArray array y

589− , All ((~) y) ys

590− , SListI ys

591− , IsProductType product ys )

592− => FromArray ('NotNull ('PGfixarray n array)) product where

593− fromArray =

594− let

595− rep _ = fmap (to . SOP . Z) . replicateMN

596− in

597− Decoding.dimensionArray rep (fromArray @array @y)

598−instance {-# OVERLAPPING #-}

599− ( FromArray array y

636+-- | A `FromFixArray` constraint gives a decoding to a Haskell `Type`

637+-- from the binary format of a PostgreSQL fixed-length array.

638+-- You should not define instances for

639+-- `FromFixArray`, just use the provided instances.

640+class FromFixArray (dims :: [Nat]) (ty :: NullityType) (y :: Type) where

641+ fromFixArray :: Decoding.Array y

642+instance FromValue pg y => FromFixArray '[] ('NotNull pg) y where

643+ fromFixArray = Decoding.valueArray (fromValue @pg @y)

644+instance FromValue pg y => FromFixArray '[] ('Null pg) (Maybe y) where

645+ fromFixArray = Decoding.nullableValueArray (fromValue @pg @y)

646+instance

647+ ( IsProductType product ys

648+ , Length ys ~ dim

600649 , All ((~) y) ys

601− , SListI ys

602− , IsProductType product ys )

603− => FromArray ('Null ('PGfixarray n array)) (Maybe product) where

604− fromArray =

650+ , FromFixArray dims ty y )

651+ => FromFixArray (dim ': dims) ty product where

652+ fromFixArray =

605653 let

606654 rep _ = fmap (to . SOP . Z) . replicateMN

607655 in

608− Just <$> Decoding.dimensionArray rep (fromArray @array @y)

656+ Decoding.dimensionArray rep (fromFixArray @dims @ty @y)

609657

610658-- | A `FromRow` constraint generically sequences the parsings of the columns

611659-- of a `RowType` into the fields of a record `Type` provided they have

612660-- the same field names. You should not define instances of `FromRow`.

613−-- Instead define `Generic` and `HasDatatypeInfo` instances which in turn

661+-- Instead define `SOP.Generic` and `SOP.HasDatatypeInfo` instances which in turn

614662-- provide `FromRow` instances.

615663class SListI result => FromRow (result :: RowType) y where

616664 -- | >>> :set -XOverloadedStrings

@@ -633,6 +681,53 @@ instance

633681 = fmap fromRecord

634682 . hsequence'

635683 . htrans (Proxy @FromField) fromField

684+------------------------------------------------------

685+-- P records

686+------------------------------------------------------

687+-- instance (FromField (col ::: pg) (col ::: hask))

688+-- => FromRow '[col ::: pg] (P (col ::: hask)) where

689+-- fromRow (pg :* Nil) = (unComp . fromField) pg

690+-- instance

691+-- ( row ~ Join row1 row2

692+-- , FromRow row1 hask1

693+-- , FromRow row2 hask2

694+-- , SListI row

695+-- ) => FromRow row (hask1, hask2) where

696+-- fromRow row = case disjoin @row1 @row2 row of

697+-- (row1, row2) -> (,) <$> fromRow row1 <*> fromRow row2

698+-- instance

699+-- ( row ~ Join row1 row23

700+-- , FromRow row1 hask1

701+-- , FromRow row23 (hask2, hask3)

702+-- , SListI row

703+-- ) => FromRow row (hask1, hask2, hask3) where

704+-- fromRow row = case disjoin @row1 @row23 row of

705+-- (row1, row23) -> do

706+-- hask1 <- fromRow row1

707+-- (hask2, hask3) <- fromRow row23

708+-- return (hask1, hask2, hask3)

709+-- instance

710+-- ( row ~ Join row1 row234

711+-- , FromRow row1 hask1

712+-- , FromRow row234 (hask2, hask3, hask4)

713+-- , SListI row

714+-- ) => FromRow row (hask1, hask2, hask3, hask4) where

715+-- fromRow row = case disjoin @row1 @row234 row of

716+-- (row1, row234) -> do

717+-- hask1 <- fromRow row1

718+-- (hask2, hask3, hask4) <- fromRow row234

719+-- return (hask1, hask2, hask3, hask4)

720+-- instance

721+-- ( row ~ Join row1 row2345

722+-- , FromRow row1 hask1

723+-- , FromRow row2345 (hask2, hask3, hask4, hask5)

724+-- , SListI row

725+-- ) => FromRow row (hask1, hask2, hask3, hask4, hask5) where

726+-- fromRow row = case disjoin @row1 @row2345 row of

727+-- (row1, row2345) -> do

728+-- hask1 <- fromRow row1

729+-- (hask2, hask3, hask4, hask5) <- fromRow row2345

730+-- return (hask1, hask2, hask3, hask4, hask5)

636731

637732-- | `Only` is a 1-tuple type, useful for encoding a single parameter with

638733-- `toParams` or decoding a single value with `fromRow`.

@@ -659,4 +754,4 @@ replicateMN

659754 :: forall x xs m. (All ((~) x) xs, Monad m, SListI xs)

660755 => m x -> m (NP I xs)

661756replicateMN mx = hsequence' $

662− hcpure (Proxy :: Proxy ((~) x)) (Comp (I <$> mx))

757+ hcpure (Proxy :: Proxy ((~) x)) (Comp (I <$> mx))

squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+351−225

@@ -29,49 +29,51 @@ Squeal data definition language.

2929

3030module Squeal.PostgreSQL.Definition

3131 ( -- * Definition

32− Definition (UnsafeDefinition, renderDefinition)

32+ Definition (..)

3333 , (>>>)

34+ , manipDefinition

3435 -- * Tables

3536 -- ** Create

37+ , createSchema

38+ , createSchemaIfNotExists

3639 , createTable

3740 , createTableIfNotExists

41+ , createView

42+ , createTypeEnum

43+ , createTypeEnumFrom

44+ , createTypeComposite

45+ , createTypeCompositeFrom

46+ , FieldTyped (..)

47+ , createDomain

3848 , TableConstraintExpression (..)

3949 , check

4050 , unique

4151 , primaryKey

4252 , foreignKey

4353 , ForeignKeyed

44− , OnDeleteClause (OnDeleteNoAction, OnDeleteRestrict, OnDeleteCascade)

45− , renderOnDeleteClause

46− , OnUpdateClause (OnUpdateNoAction, OnUpdateRestrict, OnUpdateCascade)

47− , renderOnUpdateClause

54+ , OnDeleteClause (..)

55+ , OnUpdateClause (..)

4856 -- ** Drop

57+ , dropSchema

4958 , dropTable

59+ , dropView

60+ , dropType

5061 -- ** Alter

5162 , alterTable

5263 , alterTableRename

53− , AlterTable (UnsafeAlterTable, renderAlterTable)

64+ , AlterTable (..)

5465 , addConstraint

5566 , dropConstraint

56− , AddColumn (addColumn)

67+ , AddColumn (..)

5768 , dropColumn

5869 , renameColumn

5970 , alterColumn

60− , AlterColumn (UnsafeAlterColumn, renderAlterColumn)

71+ , AlterColumn (..)

6172 , setDefault

6273 , dropDefault

6374 , setNotNull

6475 , dropNotNull

6576 , alterType

66− -- * Views

67− , createView

68− , dropView

69− -- * Types

70− , createTypeEnum

71− , createTypeEnumFrom

72− , createTypeComposite

73− , createTypeCompositeFrom

74− , dropType

7577 -- * Columns

7678 , ColumnTypeExpression (..)

7779 , nullable

@@ -95,36 +97,80 @@ import Prelude hiding ((.), id)

9597import qualified Generics.SOP as SOP

9698import qualified GHC.Generics as GHC

9799

100+import Squeal.PostgreSQL.Alias

98101import Squeal.PostgreSQL.Expression

102+import Squeal.PostgreSQL.Expression.Logic

103+import Squeal.PostgreSQL.Expression.Type

104+import Squeal.PostgreSQL.List

105+import Squeal.PostgreSQL.PG

99106import Squeal.PostgreSQL.Query

107+import Squeal.PostgreSQL.Manipulation

100108import Squeal.PostgreSQL.Render

101109import Squeal.PostgreSQL.Schema

102110

111+-- $setup

112+-- >>> import Squeal.PostgreSQL

113+

103114{-----------------------------------------

104115statements

105116-----------------------------------------}

106117

107−-- | A `Definition` is a statement that changes the schema of the

118+-- | A `Definition` is a statement that changes the schemas of the

108119-- database, like a `createTable`, `dropTable`, or `alterTable` command.

109120-- `Definition`s may be composed using the `>>>` operator.

110121newtype Definition

111− (schema0 :: SchemaType)

112− (schema1 :: SchemaType)

122+ (schemas0 :: SchemasType)

123+ (schemas1 :: SchemasType)

113124 = UnsafeDefinition { renderDefinition :: ByteString }

114125 deriving (GHC.Generic,Show,Eq,Ord,NFData)

115126

116−instance RenderSQL (Definition schema0 schema1) where

127+instance RenderSQL (Definition schemas0 schemas1) where

117128 renderSQL = renderDefinition

118129

119130instance Category Definition where

120131 id = UnsafeDefinition ";"

121132 ddl1 . ddl0 = UnsafeDefinition $

122− renderDefinition ddl0 <> "\n" <> renderDefinition ddl1

133+ renderSQL ddl0 <> "\n" <> renderSQL ddl1

134+

135+-- | A `Manipulation` without input or output can be run as a statement

136+-- along with other `Definition`s, by embedding it using `manipDefinition`.

137+manipDefinition

138+ :: Manipulation '[] schemas '[] '[]

139+ -- ^ no input or output

140+ -> Definition schemas schemas

141+manipDefinition = UnsafeDefinition . (<> ";") . renderSQL

123142

124143{-----------------------------------------

125144CREATE statements

126145-----------------------------------------}

127146

147+{- |

148+`createSchema` enters a new schema into the current database.

149+The schema name must be distinct from the name of any existing schema

150+in the current database.

151+

152+A schema is essentially a namespace: it contains named objects

153+(tables, data types, functions, and operators) whose names

154+can duplicate those of other objects existing in other schemas.

155+Named objects are accessed by `QualifiedAlias`es with the schema

156+name as a prefix.

157+-}

158+createSchema

159+ :: KnownSymbol sch

160+ => Alias sch

161+ -> Definition schemas (Create sch '[] schemas)

162+createSchema sch = UnsafeDefinition $

163+ "CREATE" <+> "SCHEMA" <+> renderSQL sch <> ";"

164+

165+{- | Idempotent version of `createSchema`. -}

166+createSchemaIfNotExists

167+ :: (KnownSymbol sch, Has sch schemas schema)

168+ => Alias sch

169+ -> Definition schemas schemas

170+createSchemaIfNotExists sch = UnsafeDefinition $

171+ "CREATE" <+> "SCHEMA" <+> "IF" <+> "NOT" <+> "EXISTS"

172+ <+> renderSQL sch <> ";"

173+

128174{- | `createTable` adds a table to the schema.

129175

130176>>> :set -XOverloadedLabels

@@ -136,7 +182,7 @@ type Table = '[] :=>

136182

137183>>> :{

138184let

139− setup :: Definition '[] '["tab" ::: 'Table Table]

185+ setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table])

140186 setup = createTable #tab

141187 (nullable int `as` #a :* nullable real `as` #b) Nil

142188in printSQL setup

@@ -144,17 +190,19 @@ in printSQL setup

144190CREATE TABLE "tab" ("a" int NULL, "b" real NULL);

145191-}

146192createTable

147− :: ( KnownSymbol table

193+ :: ( KnownSymbol sch

194+ , KnownSymbol tab

148195 , columns ~ (col ': cols)

149196 , SOP.SListI columns

150197 , SOP.SListI constraints

151− , schema1 ~ Create table ('Table (constraints :=> columns)) schema0 )

152− => Alias table -- ^ the name of the table to add

153− -> NP (Aliased (ColumnTypeExpression schema0)) columns

198+ , Has sch schemas0 schema0

199+ , schemas1 ~ Alter sch (Create tab ('Table (constraints :=> columns)) schema0) schemas0 )

200+ => QualifiedAlias sch tab -- ^ the name of the table to add

201+ -> NP (Aliased (ColumnTypeExpression schemas0)) columns

154202 -- ^ the names and datatype of each column

155− -> NP (Aliased (TableConstraintExpression schema1 table)) constraints

203+ -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints

156204 -- ^ constraints that must hold for the table

157− -> Definition schema0 schema1

205+ -> Definition schemas0 schemas1

158206createTable tab columns constraints = UnsafeDefinition $

159207 "CREATE TABLE" <+> renderCreation tab columns constraints

160208

@@ -170,11 +218,11 @@ type Table = '[] :=>

170218 , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

171219:}

172220

173−>>> type Schema = '["tab" ::: 'Table Table]

221+>>> type Schemas = Public '["tab" ::: 'Table Table]

174222

175223>>> :{

176224let

177− setup :: Definition Schema Schema

225+ setup :: Definition Schemas Schemas

178226 setup = createTableIfNotExists #tab

179227 (nullable int `as` #a :* nullable real `as` #b) Nil

180228in printSQL setup

@@ -182,31 +230,33 @@ in printSQL setup

182230CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);

183231-}

184232createTableIfNotExists

185− :: ( Has table schema ('Table (constraints :=> columns))

233+ :: ( Has sch schemas schema

234+ , Has tab schema ('Table (constraints :=> columns))

186235 , SOP.SListI columns

187236 , SOP.SListI constraints )

188− => Alias table -- ^ the name of the table to add

189− -> NP (Aliased (ColumnTypeExpression schema)) columns

237+ => QualifiedAlias sch tab -- ^ the name of the table to add

238+ -> NP (Aliased (ColumnTypeExpression schemas)) columns

190239 -- ^ the names and datatype of each column

191− -> NP (Aliased (TableConstraintExpression schema table)) constraints

240+ -> NP (Aliased (TableConstraintExpression sch tab schemas)) constraints

192241 -- ^ constraints that must hold for the table

193− -> Definition schema schema

242+ -> Definition schemas schemas

194243createTableIfNotExists tab columns constraints = UnsafeDefinition $

195244 "CREATE TABLE IF NOT EXISTS"

196245 <+> renderCreation tab columns constraints

197246

198247-- helper function for `createTable` and `createTableIfNotExists`

199248renderCreation

200− :: ( KnownSymbol table

249+ :: ( KnownSymbol sch

250+ , KnownSymbol tab

201251 , SOP.SListI columns

202252 , SOP.SListI constraints )

203− => Alias table -- ^ the name of the table to add

204− -> NP (Aliased (ColumnTypeExpression schema0)) columns

253+ => QualifiedAlias sch tab -- ^ the name of the table to add

254+ -> NP (Aliased (ColumnTypeExpression schemas0)) columns

205255 -- ^ the names and datatype of each column

206− -> NP (Aliased (TableConstraintExpression schema1 table)) constraints

256+ -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints

207257 -- ^ constraints that must hold for the table

208258 -> ByteString

209−renderCreation tab columns constraints = renderAlias tab

259+renderCreation tab columns constraints = renderSQL tab

210260 <+> parenthesized

211261 ( renderCommaSeparated renderColumnDef columns

212262 <> ( case constraints of

@@ -215,14 +265,14 @@ renderCreation tab columns constraints = renderAlias tab

215265 renderCommaSeparated renderConstraint constraints ) )

216266 <> ";"

217267 where

218− renderColumnDef :: Aliased (ColumnTypeExpression schema) x -> ByteString

268+ renderColumnDef :: Aliased (ColumnTypeExpression schemas) x -> ByteString

219269 renderColumnDef (ty `As` column) =

220− renderAlias column <+> renderColumnTypeExpression ty

270+ renderSQL column <+> renderColumnTypeExpression ty

221271 renderConstraint

222− :: Aliased (TableConstraintExpression schema columns) constraint

272+ :: Aliased (TableConstraintExpression sch tab schemas) constraint

223273 -> ByteString

224274 renderConstraint (constraint `As` alias) =

225− "CONSTRAINT" <+> renderAlias alias <+> renderTableConstraintExpression constraint

275+ "CONSTRAINT" <+> renderSQL alias <+> renderSQL constraint

226276

227277-- | Data types are a way to limit the kind of data that can be stored in a

228278-- table. For many applications, however, the constraint they provide is

@@ -237,12 +287,16 @@ renderCreation tab columns constraints = renderAlias tab

237287-- violate a constraint, an error is raised. This applies

238288-- even if the value came from the default value definition.

239289newtype TableConstraintExpression

240− (schema :: SchemaType)

241− (table :: Symbol)

242− (tableConstraint :: TableConstraint)

290+ (sch :: Symbol)

291+ (tab :: Symbol)

292+ (schemas :: SchemasType)

293+ (constraint :: TableConstraint)

243294 = UnsafeTableConstraintExpression

244295 { renderTableConstraintExpression :: ByteString }

245296 deriving (GHC.Generic,Show,Eq,Ord,NFData)

297+instance RenderSQL

298+ (TableConstraintExpression sch tab schemas constraint) where

299+ renderSQL = renderTableConstraintExpression

246300

247301{-| A `check` constraint is the most generic `TableConstraint` type.

248302It allows you to specify that the value in a certain column must satisfy

@@ -258,7 +312,7 @@ type Schema = '[

258312

259313>>> :{

260314let

261− definition :: Definition '[] Schema

315+ definition :: Definition (Public '[]) (Public Schema)

262316 definition = createTable #tab

263317 ( (int & notNullable) `as` #a :*

264318 (int & notNullable) `as` #b )

@@ -269,15 +323,16 @@ let

269323CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));

270324-}

271325check

272− :: ( Has alias schema ('Table table)

326+ :: ( Has sch schemas schema

327+ , Has tab schema ('Table table)

273328 , HasAll aliases (TableToRow table) subcolumns )

274329 => NP Alias aliases

275330 -- ^ specify the subcolumns which are getting checked

276− -> (forall tab. Condition schema '[tab ::: subcolumns] 'Ungrouped '[])

331+ -> (forall t. Condition '[] '[] 'Ungrouped schemas '[] '[t ::: subcolumns])

277332 -- ^ a closed `Condition` on those subcolumns

278− -> TableConstraintExpression schema alias ('Check aliases)

333+ -> TableConstraintExpression sch tab schemas ('Check aliases)

279334check _cols condition = UnsafeTableConstraintExpression $

280− "CHECK" <+> parenthesized (renderExpression condition)

335+ "CHECK" <+> parenthesized (renderSQL condition)

281336

282337{-| A `unique` constraint ensure that the data contained in a column,

283338or a group of columns, is unique among all the rows in the table.

@@ -292,7 +347,7 @@ type Schema = '[

292347

293348>>> :{

294349let

295− definition :: Definition '[] Schema

350+ definition :: Definition (Public '[]) (Public Schema)

296351 definition = createTable #tab

297352 ( (int & nullable) `as` #a :*

298353 (int & nullable) `as` #b )

@@ -303,13 +358,14 @@ let

303358CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));

304359-}

305360unique

306− :: ( Has alias schema ('Table table)

361+ :: ( Has sch schemas schema

362+ , Has tab schema('Table table)

307363 , HasAll aliases (TableToRow table) subcolumns )

308364 => NP Alias aliases

309365 -- ^ specify subcolumns which together are unique for each row

310− -> TableConstraintExpression schema alias ('Unique aliases)

366+ -> TableConstraintExpression sch tab schemas ('Unique aliases)

311367unique columns = UnsafeTableConstraintExpression $

312− "UNIQUE" <+> parenthesized (commaSeparated (renderAliases columns))

368+ "UNIQUE" <+> parenthesized (renderSQL columns)

313369

314370{-| A `primaryKey` constraint indicates that a column, or group of columns,

315371can be used as a unique identifier for rows in the table.

@@ -325,7 +381,7 @@ type Schema = '[

325381

326382>>> :{

327383let

328− definition :: Definition '[] Schema

384+ definition :: Definition (Public '[]) (Public Schema)

329385 definition = createTable #tab

330386 ( serial `as` #id :*

331387 (text & notNullable) `as` #name )

@@ -336,14 +392,15 @@ let

336392CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));

337393-}

338394primaryKey

339− :: ( Has alias schema ('Table table)

395+ :: ( Has sch schemas schema

396+ , Has tab schema ('Table table)

340397 , HasAll aliases (TableToColumns table) subcolumns

341398 , AllNotNull subcolumns )

342399 => NP Alias aliases

343400 -- ^ specify the subcolumns which together form a primary key.

344− -> TableConstraintExpression schema alias ('PrimaryKey aliases)

401+ -> TableConstraintExpression sch tab schemas ('PrimaryKey aliases)

345402primaryKey columns = UnsafeTableConstraintExpression $

346− "PRIMARY KEY" <+> parenthesized (commaSeparated (renderAliases columns))

403+ "PRIMARY KEY" <+> parenthesized (renderSQL columns)

347404

348405{-| A `foreignKey` specifies that the values in a column

349406(or a group of columns) must match the values appearing in some row of

@@ -370,7 +427,7 @@ type Schema =

370427

371428>>> :{

372429let

373− setup :: Definition '[] Schema

430+ setup :: Definition (Public '[]) (Public Schema)

374431 setup =

375432 createTable #users

376433 ( serial `as` #id :*

@@ -405,7 +462,7 @@ type Schema =

405462

406463>>> :{

407464let

408− setup :: Definition '[] Schema

465+ setup :: Definition (Public '[]) (Public Schema)

409466 setup =

410467 createTable #employees

411468 ( serial `as` #id :*

@@ -419,7 +476,7 @@ in printSQL setup

419476CREATE 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);

420477-}

421478foreignKey

422− :: (ForeignKeyed schema child parent

479+ :: (ForeignKeyed schemas sch schema child parent

423480 table reftable

424481 columns refcolumns

425482 constraints cols

@@ -434,23 +491,26 @@ foreignKey

434491 -- ^ what to do when reference is deleted

435492 -> OnUpdateClause

436493 -- ^ what to do when reference is updated

437− -> TableConstraintExpression schema child

494+ -> TableConstraintExpression sch child schemas

438495 ('ForeignKey columns parent refcolumns)

439496foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $

440− "FOREIGN KEY" <+> parenthesized (commaSeparated (renderAliases keys))

441− <+> "REFERENCES" <+> renderAlias parent

442− <+> parenthesized (commaSeparated (renderAliases refs))

443− <+> renderOnDeleteClause ondel

444− <+> renderOnUpdateClause onupd

497+ "FOREIGN KEY" <+> parenthesized (renderSQL keys)

498+ <+> "REFERENCES" <+> renderSQL parent

499+ <+> parenthesized (renderSQL refs)

500+ <+> renderSQL ondel

501+ <+> renderSQL onupd

445502

446503-- | A constraint synonym between types involved in a foreign key constraint.

447−type ForeignKeyed schema

504+type ForeignKeyed schemas

505+ sch

506+ schema

448507 child parent

449508 table reftable

450509 columns refcolumns

451510 constraints cols

452511 reftys tys =

453− ( Has child schema ('Table table)

512+ ( Has sch schemas schema

513+ , Has child schema ('Table table)

454514 , Has parent schema ('Table reftable)

455515 , HasAll columns (TableToColumns table) tys

456516 , reftable ~ (constraints :=> cols)

@@ -469,13 +529,12 @@ data OnDeleteClause

469529 -- row(s) referencing it should be automatically deleted as well

470530 deriving (GHC.Generic,Show,Eq,Ord)

471531instance NFData OnDeleteClause

472−

473532-- | Render `OnDeleteClause`.

474−renderOnDeleteClause :: OnDeleteClause -> ByteString

475−renderOnDeleteClause = \case

476− OnDeleteNoAction -> "ON DELETE NO ACTION"

477− OnDeleteRestrict -> "ON DELETE RESTRICT"

478− OnDeleteCascade -> "ON DELETE CASCADE"

533+instance RenderSQL OnDeleteClause where

534+ renderSQL = \case

535+ OnDeleteNoAction -> "ON DELETE NO ACTION"

536+ OnDeleteRestrict -> "ON DELETE RESTRICT"

537+ OnDeleteCascade -> "ON DELETE CASCADE"

479538

480539-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked

481540-- when a referenced column is changed (updated).

@@ -491,31 +550,46 @@ data OnUpdateClause

491550instance NFData OnUpdateClause

492551

493552-- | Render `OnUpdateClause`.

494−renderOnUpdateClause :: OnUpdateClause -> ByteString

495−renderOnUpdateClause = \case

496− OnUpdateNoAction -> "ON UPDATE NO ACTION"

497− OnUpdateRestrict -> "ON UPDATE RESTRICT"

498− OnUpdateCascade -> "ON UPDATE CASCADE"

553+instance RenderSQL OnUpdateClause where

554+ renderSQL = \case

555+ OnUpdateNoAction -> "ON UPDATE NO ACTION"

556+ OnUpdateRestrict -> "ON UPDATE RESTRICT"

557+ OnUpdateCascade -> "ON UPDATE CASCADE"

499558

500559{-----------------------------------------

501560DROP statements

502561-----------------------------------------}

503562

563+-- | >>> :{

564+-- let

565+-- definition :: Definition '["muh_schema" ::: schema, "public" ::: public] '["public" ::: public]

566+-- definition = dropSchema #muh_schema

567+-- :}

568+--

569+-- >>> printSQL definition

570+-- DROP SCHEMA "muh_schema";

571+dropSchema

572+ :: Has sch schemas schema

573+ => Alias sch

574+ -> Definition schemas (Drop sch schemas)

575+dropSchema sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"

576+

504577-- | `dropTable` removes a table from the schema.

505578--

506579-- >>> :{

507580-- let

508−-- definition :: Definition '["muh_table" ::: 'Table t] '[]

581+-- definition :: Definition '["public" ::: '["muh_table" ::: 'Table t]] (Public '[])

509582-- definition = dropTable #muh_table

510583-- :}

511584--

512585-- >>> printSQL definition

513586-- DROP TABLE "muh_table";

514587dropTable

515− :: Has table schema ('Table t)

516− => Alias table -- ^ table to remove

517− -> Definition schema (Drop table schema)

518−dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderAlias tab <> ";"

588+ :: ( Has sch schemas schema

589+ , Has tab schema ('Table table))

590+ => QualifiedAlias sch tab -- ^ table to remove

591+ -> Definition schemas (Alter sch (Drop tab schema) schemas)

592+dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderSQL tab <> ";"

519593

520594{-----------------------------------------

521595ALTER statements

@@ -523,13 +597,13 @@ ALTER statements

523597

524598-- | `alterTable` changes the definition of a table from the schema.

525599alterTable

526− :: KnownSymbol alias

527− => Alias alias -- ^ table to alter

528− -> AlterTable alias table schema -- ^ alteration to perform

529− -> Definition schema (Alter alias ('Table table) schema)

600+ :: (Has sch schemas schema, Has tab schema ('Table table0))

601+ => QualifiedAlias sch tab -- ^ table to alter

602+ -> AlterTable sch tab schemas table1 -- ^ alteration to perform

603+ -> Definition schemas (Alter sch (Alter tab ('Table table1) schema) schemas)

530604alterTable tab alteration = UnsafeDefinition $

531605 "ALTER TABLE"

532− <+> renderAlias tab

606+ <+> renderSQL tab

533607 <+> renderAlterTable alteration

534608 <> ";"

535609

@@ -543,15 +617,16 @@ alterTableRename

543617 -> Alias table1 -- ^ what to rename it

544618 -> Definition schema (Rename table0 table1 schema)

545619alterTableRename table0 table1 = UnsafeDefinition $

546− "ALTER TABLE" <+> renderAlias table0

547− <+> "RENAME TO" <+> renderAlias table1 <> ";"

620+ "ALTER TABLE" <+> renderSQL table0

621+ <+> "RENAME TO" <+> renderSQL table1 <> ";"

548622

549623-- | An `AlterTable` describes the alteration to perform on the columns

550624-- of a table.

551625newtype AlterTable

552− (alias :: Symbol)

553− (table :: TableType)

554− (schema :: SchemaType) =

626+ (sch :: Symbol)

627+ (tab :: Symbol)

628+ (schemas :: SchemasType)

629+ (table :: TableType) =

555630 UnsafeAlterTable {renderAlterTable :: ByteString}

556631 deriving (GHC.Generic,Show,Eq,Ord,NFData)

557632

@@ -560,46 +635,48 @@ newtype AlterTable

560635-- >>> :{

561636-- let

562637-- definition :: Definition

563−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

564−-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

638+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

639+-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: 'Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

565640-- definition = alterTable #tab (addConstraint #positive (check #col (#col .> 0)))

566641-- in printSQL definition

567642-- :}

568643-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));

569644addConstraint

570645 :: ( KnownSymbol alias

646+ , Has sch schemas schema

571647 , Has tab schema ('Table table0)

572648 , table0 ~ (constraints :=> columns)

573649 , table1 ~ (Create alias constraint constraints :=> columns) )

574650 => Alias alias

575− -> TableConstraintExpression schema tab constraint

651+ -> TableConstraintExpression sch tab schemas constraint

576652 -- ^ constraint to add

577− -> AlterTable tab table1 schema

653+ -> AlterTable sch tab schemas table1

578654addConstraint alias constraint = UnsafeAlterTable $

579− "ADD" <+> "CONSTRAINT" <+> renderAlias alias

580− <+> renderTableConstraintExpression constraint

655+ "ADD" <+> "CONSTRAINT" <+> renderSQL alias

656+ <+> renderSQL constraint

581657

582658-- | A `dropConstraint` drops a table constraint.

583659--

584660-- >>> :{

585661-- let

586662-- definition :: Definition

587−-- '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

588−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

663+-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

664+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

589665-- definition = alterTable #tab (dropConstraint #positive)

590666-- in printSQL definition

591667-- :}

592668-- ALTER TABLE "tab" DROP CONSTRAINT "positive";

593669dropConstraint

594670 :: ( KnownSymbol constraint

671+ , Has sch schemas schema

595672 , Has tab schema ('Table table0)

596673 , table0 ~ (constraints :=> columns)

597674 , table1 ~ (Drop constraint constraints :=> columns) )

598675 => Alias constraint

599676 -- ^ constraint to drop

600− -> AlterTable tab table1 schema

677+ -> AlterTable sch tab schemas table1

601678dropConstraint constraint = UnsafeAlterTable $

602− "DROP" <+> "CONSTRAINT" <+> renderAlias constraint

679+ "DROP" <+> "CONSTRAINT" <+> renderSQL constraint

603680

604681-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.

605682class AddColumn ty where

@@ -609,10 +686,10 @@ class AddColumn ty where

609686 -- >>> :{

610687 -- let

611688 -- definition :: Definition

612− -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]

613− -- '["tab" ::: 'Table ('[] :=>

689+ -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]

690+ -- '["public" ::: '["tab" ::: 'Table ('[] :=>

614691 -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

615− -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]

692+ -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]]

616693 -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))

617694 -- in printSQL definition

618695 -- :}

@@ -621,24 +698,24 @@ class AddColumn ty where

621698 -- >>> :{

622699 -- let

623700 -- definition :: Definition

624− -- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]

625− -- '["tab" ::: 'Table ('[] :=>

701+ -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]

702+ -- '["public" ::: '["tab" ::: 'Table ('[] :=>

626703 -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

627− -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]

704+ -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]

628705 -- definition = alterTable #tab (addColumn #col2 (text & nullable))

629706 -- in printSQL definition

630707 -- :}

631708 -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;

632709 addColumn

633710 :: ( KnownSymbol column

711+ , Has sch schemas schema

634712 , Has tab schema ('Table table0)

635− , table0 ~ (constraints :=> columns)

636− , table1 ~ (constraints :=> Create column ty columns) )

713+ , table0 ~ (constraints :=> columns) )

637714 => Alias column -- ^ column to add

638− -> ColumnTypeExpression schema ty -- ^ type of the new column

639− -> AlterTable tab table1 schema

715+ -> ColumnTypeExpression schemas ty -- ^ type of the new column

716+ -> AlterTable sch tab schemas (constraints :=> Create column ty columns)

640717 addColumn column ty = UnsafeAlterTable $

641− "ADD COLUMN" <+> renderAlias column <+> renderColumnTypeExpression ty

718+ "ADD COLUMN" <+> renderSQL column <+> renderColumnTypeExpression ty

642719instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)

643720instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)

644721

@@ -650,31 +727,32 @@ instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)

650727-- >>> :{

651728-- let

652729-- definition :: Definition

653−-- '["tab" ::: 'Table ('[] :=>

730+-- '["public" ::: '["tab" ::: 'Table ('[] :=>

654731-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

655−-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]

656−-- '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]

732+-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]

733+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]

657734-- definition = alterTable #tab (dropColumn #col2)

658735-- in printSQL definition

659736-- :}

660737-- ALTER TABLE "tab" DROP COLUMN "col2";

661738dropColumn

662739 :: ( KnownSymbol column

740+ , Has sch schemas schema

663741 , Has tab schema ('Table table0)

664742 , table0 ~ (constraints :=> columns)

665743 , table1 ~ (constraints :=> Drop column columns) )

666744 => Alias column -- ^ column to remove

667− -> AlterTable tab table1 schema

745+ -> AlterTable sch tab schemas table1

668746dropColumn column = UnsafeAlterTable $

669− "DROP COLUMN" <+> renderAlias column

747+ "DROP COLUMN" <+> renderSQL column

670748

671749-- | A `renameColumn` renames a column.

672750--

673751-- >>> :{

674752-- let

675753-- definition :: Definition

676−-- '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]

677−-- '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]

754+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]]

755+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]]

678756-- definition = alterTable #tab (renameColumn #foo #bar)

679757-- in printSQL definition

680758-- :}

@@ -682,30 +760,32 @@ dropColumn column = UnsafeAlterTable $

682760renameColumn

683761 :: ( KnownSymbol column0

684762 , KnownSymbol column1

763+ , Has sch schemas schema

685764 , Has tab schema ('Table table0)

686765 , table0 ~ (constraints :=> columns)

687766 , table1 ~ (constraints :=> Rename column0 column1 columns) )

688767 => Alias column0 -- ^ column to rename

689768 -> Alias column1 -- ^ what to rename the column

690− -> AlterTable tab table1 schema

769+ -> AlterTable sch tab schemas table1

691770renameColumn column0 column1 = UnsafeAlterTable $

692− "RENAME COLUMN" <+> renderAlias column0 <+> "TO" <+> renderAlias column1

771+ "RENAME COLUMN" <+> renderSQL column0 <+> "TO" <+> renderSQL column1

693772

694773-- | An `alterColumn` alters a single column.

695774alterColumn

696775 :: ( KnownSymbol column

776+ , Has sch schemas schema

697777 , Has tab schema ('Table table0)

698778 , table0 ~ (constraints :=> columns)

699779 , Has column columns ty0

700− , tables1 ~ (constraints :=> Alter column ty1 columns))

780+ , table1 ~ (constraints :=> Alter column ty1 columns))

701781 => Alias column -- ^ column to alter

702− -> AlterColumn schema ty0 ty1 -- ^ alteration to perform

703− -> AlterTable tab table1 schema

782+ -> AlterColumn schemas ty0 ty1 -- ^ alteration to perform

783+ -> AlterTable sch tab schemas table1

704784alterColumn column alteration = UnsafeAlterTable $

705− "ALTER COLUMN" <+> renderAlias column <+> renderAlterColumn alteration

785+ "ALTER COLUMN" <+> renderSQL column <+> renderAlterColumn alteration

706786

707787-- | An `AlterColumn` describes the alteration to perform on a single column.

708−newtype AlterColumn (schema :: SchemaType) (ty0 :: ColumnType) (ty1 :: ColumnType) =

788+newtype AlterColumn (schemas :: SchemasType) (ty0 :: ColumnType) (ty1 :: ColumnType) =

709789 UnsafeAlterColumn {renderAlterColumn :: ByteString}

710790 deriving (GHC.Generic,Show,Eq,Ord,NFData)

711791

@@ -716,15 +796,15 @@ newtype AlterColumn (schema :: SchemaType) (ty0 :: ColumnType) (ty1 :: ColumnTyp

716796-- >>> :{

717797-- let

718798-- definition :: Definition

719−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

720−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]

799+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]

800+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]

721801-- definition = alterTable #tab (alterColumn #col (setDefault 5))

722802-- in printSQL definition

723803-- :}

724804-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;

725805setDefault

726− :: Expression schema '[] 'Ungrouped '[] ty -- ^ default value to set

727− -> AlterColumn schema (constraint :=> ty) ('Def :=> ty)

806+ :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty -- ^ default value to set

807+ -> AlterColumn schemas (constraint :=> ty) ('Def :=> ty)

728808setDefault expression = UnsafeAlterColumn $

729809 "SET DEFAULT" <+> renderExpression expression

730810

@@ -733,13 +813,13 @@ setDefault expression = UnsafeAlterColumn $

733813-- >>> :{

734814-- let

735815-- definition :: Definition

736−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]

737−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

816+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]

817+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]

738818-- definition = alterTable #tab (alterColumn #col dropDefault)

739819-- in printSQL definition

740820-- :}

741821-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;

742−dropDefault :: AlterColumn schema ('Def :=> ty) ('NoDef :=> ty)

822+dropDefault :: AlterColumn schemas ('Def :=> ty) ('NoDef :=> ty)

743823dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

744824

745825-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.

@@ -749,14 +829,14 @@ dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

749829-- >>> :{

750830-- let

751831-- definition :: Definition

752−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

753−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

832+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]

833+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

754834-- definition = alterTable #tab (alterColumn #col setNotNull)

755835-- in printSQL definition

756836-- :}

757837-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;

758838setNotNull

759− :: AlterColumn schema (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)

839+ :: AlterColumn schemas (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)

760840setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

761841

762842-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.

@@ -764,14 +844,14 @@ setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

764844-- >>> :{

765845-- let

766846-- definition :: Definition

767−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

768−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

847+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

848+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]

769849-- definition = alterTable #tab (alterColumn #col dropNotNull)

770850-- in printSQL definition

771851-- :}

772852-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;

773853dropNotNull

774− :: AlterColumn schema (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)

854+ :: AlterColumn schemas (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)

775855dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

776856

777857-- | An `alterType` converts a column to a different data type.

@@ -781,37 +861,37 @@ dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

781861-- >>> :{

782862-- let

783863-- definition :: Definition

784−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]

785−-- '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]

864+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]

865+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]]

786866-- definition =

787867-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))

788868-- in printSQL definition

789869-- :}

790870-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;

791−alterType :: ColumnTypeExpression schema ty -> AlterColumn schema ty0 ty

871+alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty

792872alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty

793873

794−-- | Create a view.

795−--

796−-- >>> :{

797−-- let

798−-- definition :: Definition

799−-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]

800−-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])

801−-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]

802−-- definition =

803−-- createView #bc (select (#b :* #c) (from (table #abc)))

804−-- in printSQL definition

805−-- :}

806−-- CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";

874+{- | Create a view.

875+>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]

876+>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]

877+>>> :{

878+let

879+ definition :: Definition

880+ '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]

881+ '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc" ::: 'View BC]]

882+ definition =

883+ createView #bc (select_ (#b :* #c) (from (table #abc)))

884+in printSQL definition

885+:}

886+CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";

887+-}

807888createView

808− :: KnownSymbol view

809− => Alias view -- ^ the name of the view to add

810− -> Query schema '[] row

811− -- ^ query

812− -> Definition schema (Create view ('View row) schema)

889+ :: (KnownSymbol sch, KnownSymbol vw, Has sch schemas schema)

890+ => QualifiedAlias sch vw -- ^ the name of the view to add

891+ -> Query '[] '[] schemas '[] view -- ^ query

892+ -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)

813893createView alias query = UnsafeDefinition $

814− "CREATE" <+> "VIEW" <+> renderAlias alias <+> "AS"

894+ "CREATE" <+> "VIEW" <+> renderSQL alias <+> "AS"

815895 <+> renderQuery query <> ";"

816896

817897-- | Drop a view.

@@ -819,50 +899,56 @@ createView alias query = UnsafeDefinition $

819899-- >>> :{

820900-- let

821901-- definition :: Definition

822−-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])

823−-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]

824−-- '[ "abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]

902+-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])

903+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]

904+-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]

825905-- definition = dropView #bc

826906-- in printSQL definition

827907-- :}

828908-- DROP VIEW "bc";

829909dropView

830− :: Has view schema ('View v)

831− => Alias view -- ^ view to remove

832− -> Definition schema (Drop view schema)

833−dropView v = UnsafeDefinition $ "DROP VIEW" <+> renderAlias v <> ";"

910+ :: (Has sch schemas schema, Has vw schema ('View view))

911+ => QualifiedAlias sch vw -- ^ view to remove

912+ -> Definition schemas (Alter sch (Drop vw schema) schemas)

913+dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderSQL vw <> ";"

834914

835915-- | Enumerated types are created using the `createTypeEnum` command, for example

836916--

837−-- >>> printSQL $ createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy")

917+-- >>> printSQL $ (createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy") :: Definition (Public '[]) '["public" ::: '["mood" ::: 'Typedef ('PGenum '["sad","ok","happy"])]])

838918-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');

839919createTypeEnum

840− :: (KnownSymbol enum, SOP.All KnownSymbol labels)

841− => Alias enum

920+ :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)

921+ => QualifiedAlias sch enum

842922 -- ^ name of the user defined enumerated type

843923 -> NP PGlabel labels

844924 -- ^ labels of the enumerated type

845− -> Definition schema (Create enum ('Typedef ('PGenum labels)) schema)

925+ -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)

846926createTypeEnum enum labels = UnsafeDefinition $

847− "CREATE" <+> "TYPE" <+> renderAlias enum <+> "AS" <+> "ENUM" <+>

848− parenthesized (commaSeparated (renderLabels labels)) <> ";"

927+ "CREATE" <+> "TYPE" <+> renderSQL enum <+> "AS" <+> "ENUM" <+>

928+ parenthesized (renderSQL labels) <> ";"

849929

850930-- | Enumerated types can also be generated from a Haskell type, for example

851931--

852932-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

853933-- >>> instance SOP.Generic Schwarma

854934-- >>> instance SOP.HasDatatypeInfo Schwarma

855−-- >>> printSQL $ createTypeEnumFrom @Schwarma #schwarma

935+-- >>> :{

936+-- let

937+-- createSchwarma :: Definition (Public '[]) '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]]

938+-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma

939+-- in

940+-- printSQL createSchwarma

941+-- :}

856942-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');

857943createTypeEnumFrom

858− :: forall hask enum schema.

944+ :: forall hask sch enum schemas schema.

859945 ( SOP.Generic hask

860946 , SOP.All KnownSymbol (LabelsPG hask)

861947 , KnownSymbol enum

862− )

863− => Alias enum

948+ , Has sch schemas schema )

949+ => QualifiedAlias sch enum

864950 -- ^ name of the user defined enumerated type

865− -> Definition schema (Create enum ('Typedef (PG (Enumerated hask))) schema)

951+ -> Definition schemas (Alter sch (Create enum ('Typedef (PG (Enumerated hask))) schema) schemas)

866952createTypeEnumFrom enum = createTypeEnum enum

867953 (SOP.hpure label :: NP PGlabel (LabelsPG hask))

868954

@@ -877,7 +963,7 @@ type PGcomplex = 'PGcomposite

877963

878964>>> :{

879965let

880− setup :: Definition '[] '["complex" ::: 'Typedef PGcomplex]

966+ setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]

881967 setup = createTypeComposite #complex

882968 (float8 `as` #real :* float8 `as` #imaginary)

883969in printSQL setup

@@ -885,42 +971,80 @@ in printSQL setup

885971CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);

886972-}

887973createTypeComposite

888− :: (KnownSymbol ty, SOP.SListI fields)

889− => Alias ty

974+ :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)

975+ => QualifiedAlias sch ty

890976 -- ^ name of the user defined composite type

891− -> NP (Aliased (TypeExpression schema)) fields

977+ -> NP (Aliased (TypeExpression schemas)) fields

892978 -- ^ list of attribute names and data types

893− -> Definition schema (Create ty ('Typedef ('PGcomposite fields)) schema)

979+ -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)

894980createTypeComposite ty fields = UnsafeDefinition $

895− "CREATE" <+> "TYPE" <+> renderAlias ty <+> "AS" <+> parenthesized

981+ "CREATE" <+> "TYPE" <+> renderSQL ty <+> "AS" <+> parenthesized

896982 (renderCommaSeparated renderField fields) <> ";"

897983 where

898− renderField :: Aliased (TypeExpression schema) x -> ByteString

984+ renderField :: Aliased (TypeExpression schemas) x -> ByteString

899985 renderField (typ `As` alias) =

900− renderAlias alias <+> renderTypeExpression typ

986+ renderSQL alias <+> renderSQL typ

901987

902988-- | Composite types can also be generated from a Haskell type, for example

903989--

904990-- >>> data Complex = Complex {real :: Double, imaginary :: Double} deriving GHC.Generic

905991-- >>> instance SOP.Generic Complex

906992-- >>> instance SOP.HasDatatypeInfo Complex

907−-- >>> printSQL $ createTypeCompositeFrom @Complex #complex

993+-- >>> type Schema = '["complex" ::: 'Typedef (PG (Composite Complex))]

994+-- >>> :{

995+-- let

996+-- createComplex :: Definition (Public '[]) (Public Schema)

997+-- createComplex = createTypeCompositeFrom @Complex #complex

998+-- in

999+-- printSQL createComplex

1000+-- :}

9081001-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);

9091002createTypeCompositeFrom

910− :: forall hask ty schema.

911− ( SOP.All (FieldTyped schema) (RowPG hask)

912− , KnownSymbol ty )

913− => Alias ty

1003+ :: forall hask sch ty schemas schema.

1004+ ( SOP.All (FieldTyped schemas) (RowPG hask)

1005+ , KnownSymbol ty

1006+ , Has sch schemas schema )

1007+ => QualifiedAlias sch ty

9141008 -- ^ name of the user defined composite type

915− -> Definition schema (Create ty ( 'Typedef (PG (Composite hask))) schema)

1009+ -> Definition schemas (Alter sch (Create ty ( 'Typedef (PG (Composite hask))) schema) schemas)

9161010createTypeCompositeFrom ty = createTypeComposite ty

917− (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schema)) fieldtype

918− :: NP (Aliased (TypeExpression schema)) (RowPG hask))

1011+ (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype

1012+ :: NP (Aliased (TypeExpression schemas)) (RowPG hask))

1013+

1014+{-|

1015+`createDomain` creates a new domain. A domain is essentially a data type

1016+with constraints (restrictions on the allowed set of values).

1017+

1018+Domains are useful for abstracting common constraints on fields

1019+into a single location for maintenance. For example, several tables might

1020+contain email address columns, all requiring the same `check` constraint

1021+to verify the address syntax. Define a domain rather than setting up

1022+each table's constraint individually.

9191023

920−class FieldTyped schema ty where

921− fieldtype :: Aliased (TypeExpression schema) ty

922−instance (KnownSymbol alias, PGTyped schema ty)

923− => FieldTyped schema (alias ::: ty) where

1024+>>> :{

1025+let

1026+ createPositive :: Definition (Public '[]) (Public '["positive" ::: 'Typedef 'PGfloat4])

1027+ createPositive = createDomain #positive real (#value .> 0 .&& (#value & isNotNull))

1028+in printSQL createPositive

1029+:}

1030+CREATE DOMAIN "positive" AS real CHECK ((("value" > 0) AND "value" IS NOT NULL));

1031+-}

1032+createDomain

1033+ :: (Has sch schemas schema, KnownSymbol dom)

1034+ => QualifiedAlias sch dom

1035+ -> (forall nullity. TypeExpression schemas (nullity ty))

1036+ -> (forall tab. Condition '[] '[] 'Ungrouped schemas '[] '[tab ::: '["value" ::: 'Null ty]])

1037+ -> Definition schemas (Alter sch (Create alias ('Typedef ty) schema) schemas)

1038+createDomain dom ty condition =

1039+ UnsafeDefinition $ "CREATE DOMAIN" <+> renderSQL dom

1040+ <+> "AS" <+> renderTypeExpression ty

1041+ <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"

1042+

1043+-- | Lift `PGTyped` to a field

1044+class FieldTyped schemas ty where

1045+ fieldtype :: Aliased (TypeExpression schemas) ty

1046+instance (KnownSymbol alias, PGTyped schemas ty)

1047+ => FieldTyped schemas (alias ::: ty) where

9241048 fieldtype = pgtype `As` Alias

9251049

9261050-- | Drop a type.

@@ -928,57 +1052,59 @@ instance (KnownSymbol alias, PGTyped schema ty)

9281052-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

9291053-- >>> instance SOP.Generic Schwarma

9301054-- >>> instance SOP.HasDatatypeInfo Schwarma

931−-- >>> printSQL (dropType #schwarma :: Definition '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))] '[])

1055+-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))

9321056-- DROP TYPE "schwarma";

9331057dropType

934− :: Has tydef schema ('Typedef ty)

935− => Alias tydef

1058+ :: (Has sch schemas schema, Has td schema ('Typedef ty))

1059+ => QualifiedAlias sch td

9361060 -- ^ name of the user defined type

937− -> Definition schema (Drop tydef schema)

938−dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderAlias tydef <> ";"

1061+ -> Definition schemas (Alter sch (Drop td schema) schemas)

1062+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"

9391063

9401064-- | `ColumnTypeExpression`s are used in `createTable` commands.

941−newtype ColumnTypeExpression (schema :: SchemaType) (ty :: ColumnType)

1065+newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)

9421066 = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }

9431067 deriving (GHC.Generic,Show,Eq,Ord,NFData)

1068+instance RenderSQL (ColumnTypeExpression schemas ty) where

1069+ renderSQL = renderColumnTypeExpression

9441070

9451071-- | used in `createTable` commands as a column constraint to note that

9461072-- @NULL@ may be present in a column

9471073nullable

948− :: TypeExpression schema (nullity ty)

949− -> ColumnTypeExpression schema ('NoDef :=> 'Null ty)

950−nullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NULL"

1074+ :: TypeExpression schemas (nullity ty)

1075+ -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)

1076+nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"

9511077

9521078-- | used in `createTable` commands as a column constraint to ensure

9531079-- @NULL@ is not present in a column

9541080notNullable

955− :: TypeExpression schema (nullity ty)

956− -> ColumnTypeExpression schema ('NoDef :=> 'NotNull ty)

957−notNullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NOT NULL"

1081+ :: TypeExpression schemas (nullity ty)

1082+ -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)

1083+notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"

9581084

9591085-- | used in `createTable` commands as a column constraint to give a default

9601086default_

961− :: Expression schema '[] 'Ungrouped '[] ty

962− -> ColumnTypeExpression schema ('NoDef :=> ty)

963− -> ColumnTypeExpression schema ('Def :=> ty)

1087+ :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty

1088+ -> ColumnTypeExpression schemas ('NoDef :=> ty)

1089+ -> ColumnTypeExpression schemas ('Def :=> ty)

9641090default_ x ty = UnsafeColumnTypeExpression $

965− renderColumnTypeExpression ty <+> "DEFAULT" <+> renderExpression x

1091+ renderSQL ty <+> "DEFAULT" <+> renderExpression x

9661092

9671093-- | not a true type, but merely a notational convenience for creating

9681094-- unique identifier columns with type `PGint2`

9691095serial2, smallserial

970− :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint2)

1096+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)

9711097serial2 = UnsafeColumnTypeExpression "serial2"

9721098smallserial = UnsafeColumnTypeExpression "smallserial"

9731099-- | not a true type, but merely a notational convenience for creating

9741100-- unique identifier columns with type `PGint4`

9751101serial4, serial

976− :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint4)

1102+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)

9771103serial4 = UnsafeColumnTypeExpression "serial4"

9781104serial = UnsafeColumnTypeExpression "serial"

9791105-- | not a true type, but merely a notational convenience for creating

9801106-- unique identifier columns with type `PGint8`

9811107serial8, bigserial

982− :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint8)

1108+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)

9831109serial8 = UnsafeColumnTypeExpression "serial8"

9841110bigserial = UnsafeColumnTypeExpression "bigserial"

squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+261−1621

@@ -1,14 +1,13 @@

11{-|

2−Module: Squeal.PostgreSQL.Query

2+Module: Squeal.PostgreSQL.Expression

33Description: Squeal expressions

4−Copyright: (c) Eitan Chatav, 2017

4+Copyright: (c) Eitan Chatav, 2019

55Maintainer: eitan@morphism.tech

66Stability: experimental

88Squeal expressions are the atoms used to build statements.

99-}

1010

11−{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}

1211{-# LANGUAGE

1312 AllowAmbiguousTypes

1413 , ConstraintKinds

@@ -16,11 +15,13 @@ Squeal expressions are the atoms used to build statements.

1615 , FlexibleContexts

1716 , FlexibleInstances

1817 , FunctionalDependencies

18+ , GADTs

1919 , GeneralizedNewtypeDeriving

2020 , LambdaCase

2121 , MagicHash

2222 , OverloadedStrings

2323 , ScopedTypeVariables

24+ , StandaloneDeriving

2425 , TypeApplications

2526 , TypeFamilies

2627 , TypeInType

@@ -31,543 +32,284 @@ Squeal expressions are the atoms used to build statements.

3132

3233module Squeal.PostgreSQL.Expression

3334 ( -- * Expression

34− Expression (UnsafeExpression, renderExpression)

35− , HasParameter (parameter)

36− , param

37− -- ** Null

38− , null_

39− , notNull

40− , coalesce

41− , fromNull

42− , isNull

43− , isNotNull

44− , matchNull

45− , nullIf

46− -- ** Collections

47− , array

48− , index

49− , row

50− , field

51− -- ** Functions

52− , unsafeBinaryOp

53− , unsafeUnaryOp

35+ Expression (..)

36+ , Expr

37+ , (:-->)

5438 , unsafeFunction

55− , unsafeVariadicFunction

56− , atan2_

57− , cast

58− , quot_

59− , rem_

60− , trunc

61− , round_

62− , ceiling_

63− , greatest

64− , least

65− -- ** Conditions

66− , true

67− , false

68− , not_

69− , (.&&)

70− , (.||)

71− , Condition

72− , caseWhenThenElse

73− , ifThenElse

74− , (.==)

75− , (./=)

76− , (.>=)

77− , (.<)

78− , (.<=)

79− , (.>)

80− -- ** Time

81− , currentDate

82− , currentTime

83− , currentTimestamp

84− , localTime

85− , localTimestamp

86− -- ** Text

87− , lower

88− , upper

89− , charLength

90− , like

91− -- ** Json

92− -- *** Json and Jsonb operators

93− , (.->)

94− , (.->>)

95− , (.#>)

96− , (.#>>)

97− -- *** Jsonb operators

98− , (.@>)

99− , (.<@)

100− , (.?)

101− , (.?|)

102− , (.?&)

103− , (.-.)

104− , (#-.)

105− -- *** Functions

106− , jsonLit

107− , jsonbLit

108− , toJson

109− , toJsonb

110− , arrayToJson

111− , rowToJson

112− , jsonBuildArray

113− , jsonbBuildArray

114− , jsonBuildObject

115− , jsonbBuildObject

116− , jsonObject

117− , jsonbObject

118− , jsonZipObject

119− , jsonbZipObject

120− , jsonArrayLength

121− , jsonbArrayLength

122− , jsonExtractPath

123− , jsonbExtractPath

124− , jsonExtractPathAsText

125− , jsonbExtractPathAsText

126− , jsonTypeof

127− , jsonbTypeof

128− , jsonStripNulls

129− , jsonbStripNulls

130− , jsonbSet

131− , jsonbInsert

132− , jsonbPretty

133− -- ** Aggregation

134− , unsafeAggregate, unsafeAggregateDistinct

135− , sum_, sumDistinct

136− , PGAvg (avg, avgDistinct)

137− , bitAnd, bitOr, boolAnd, boolOr

138− , bitAndDistinct, bitOrDistinct, boolAndDistinct, boolOrDistinct

139− , countStar

140− , count, countDistinct

141− , every, everyDistinct

142− , max_, maxDistinct, min_, minDistinct

143− -- * Types

144− , TypeExpression (UnsafeTypeExpression, renderTypeExpression)

145− , PGTyped (pgtype)

146− , typedef

147− , typetable

148− , typeview

149− , bool

150− , int2

151− , smallint

152− , int4

153− , int

154− , integer

155− , int8

156− , bigint

157− , numeric

158− , float4

159− , real

160− , float8

161− , doublePrecision

162− , text

163− , char

164− , character

165− , varchar

166− , characterVarying

167− , bytea

168− , timestamp

169− , timestampWithTimeZone

170− , date

171− , time

172− , timeWithTimeZone

173− , interval

174− , uuid

175− , inet

176− , json

177− , jsonb

178− , vararray

179− , fixarray

39+ , unsafeUnaryOpL

40+ , unsafeUnaryOpR

41+ , Operator

42+ , unsafeBinaryOp

43+ , FunctionVar

44+ , unsafeFunctionVar

45+ , FunctionN

46+ , unsafeFunctionN

47+ , PGSubset (..)

18048 -- * Re-export

18149 , (&)

182− , NP ((:*), Nil)

50+ , K (..)

51+ , unK

18352 ) where

18453

18554import Control.Category

18655import Control.DeepSeq

18756import Data.ByteString (ByteString)

188−import Data.ByteString.Lazy (toStrict)

18957import Data.Function ((&))

19058import Data.Semigroup hiding (All)

191−import qualified Data.Aeson as JSON

192−import Data.Ratio

19359import Data.String

194−import Data.Word

195−import Generics.SOP hiding (from)

60+import Generics.SOP hiding (All, from)

19661import GHC.OverloadedLabels

19762import GHC.TypeLits

63+import Numeric

19864import Prelude hiding (id, (.))

19965

20066import qualified GHC.Generics as GHC

20167

68+import Squeal.PostgreSQL.Alias

69+import Squeal.PostgreSQL.List

20270import Squeal.PostgreSQL.Render

20371import Squeal.PostgreSQL.Schema

20472

73+-- $setup

74+-- >>> import Squeal.PostgreSQL

75+

20576{-----------------------------------------

20677column expressions

20778-----------------------------------------}

20879

20980{- | `Expression`s are used in a variety of contexts,

210−such as in the target list of the `Squeal.PostgreSQL.Query.select` command,

81+such as in the target `Squeal.PostgreSQL.Query.List` of the

82+`Squeal.PostgreSQL.Query.select` command,

21183as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or

21284`Squeal.PostgreSQL.Manipulation.update`,

213−or in search `Condition`s in a number of commands.

85+or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.

21486

21587The expression syntax allows the calculation of

21688values from primitive expression using arithmetic, logical,

21789and other operations.

90+

91+The type parameters of `Expression` are

92+

93+* @outer :: @ `FromType`, the @from@ clauses of any outer queries in which

94+ the `Expression` is a correlated subquery expression;

95+* @commons :: @ `FromType`, the `Squeal.PostgreSQL.Query.CommonTableExpression`s

96+ that are in scope for the `Expression`;

97+* @grp :: @ `Grouping`, the `Grouping` of the @from@ clause which may limit

98+ which columns may be referenced by alias;

99+* @schemas :: @ `SchemasType`, the schemas of your database that are in

100+ scope for the `Expression`;

101+* @from :: @ `FromType`, the @from@ clause which the `Expression` may use

102+ to reference columns by alias;

103+* @ty :: @ `NullityType`, the type of the `Expression`.

218104-}

219105newtype Expression

220− (schema :: SchemaType)

221− (from :: FromType)

222− (grouping :: Grouping)

106+ (outer :: FromType)

107+ (commons :: FromType)

108+ (grp :: Grouping)

109+ (schemas :: SchemasType)

223110 (params :: [NullityType])

111+ (from :: FromType)

224112 (ty :: NullityType)

225113 = UnsafeExpression { renderExpression :: ByteString }

226114 deriving (GHC.Generic,Show,Eq,Ord,NFData)

227−

228−instance RenderSQL (Expression schema from grouping params ty) where

115+instance RenderSQL (Expression outer commons grp schemas params from ty) where

229116 renderSQL = renderExpression

230117

231−{- | A `HasParameter` constraint is used to indicate a value that is

232−supplied externally to a SQL statement.

233−`Squeal.PostgreSQL.PQ.manipulateParams`,

234−`Squeal.PostgreSQL.PQ.queryParams` and

235−`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values

236−separately from the SQL command string, in which case `param`s are used to

237−refer to the out-of-line data values.

118+-- | An `Expr` is a closed `Expression`.

119+-- It is a F@RankNType@ but don't be scared.

120+-- Think of it as an expression which sees no

121+-- namespaces, so you can't use parameters

122+-- or alias references. It can be used as

123+-- a simple piece of more complex `Expression`s.

124+type Expr x

125+ = forall outer commons grp schemas params from

126+ . Expression outer commons grp schemas params from x

127+ -- ^ cannot reference aliases

128+

129+-- | A @RankNType@ for binary operators.

130+type Operator x1 x2 y

131+ = forall outer commons grp schemas params from

132+ . Expression outer commons grp schemas params from x1

133+ -- ^ left input

134+ -> Expression outer commons grp schemas params from x2

135+ -- ^ right input

136+ -> Expression outer commons grp schemas params from y

137+ -- ^ output

138+

139+-- | A @RankNType@ for functions with a single argument.

140+-- These could be either function calls or unary operators.

141+-- This is a subtype of the usual Haskell function type `Prelude.->`,

142+-- indeed a subcategory as it is closed under the usual

143+-- `Prelude..` and `Prelude.id`.

144+type (:-->) x y

145+ = forall outer commons grp schemas params from

146+ . Expression outer commons grp schemas params from x

147+ -- ^ input

148+ -> Expression outer commons grp schemas params from y

149+ -- ^ output

150+

151+{- | A @RankNType@ for functions with a fixed-length list of heterogeneous arguments.

152+Use the `*:` operator to end your argument lists, like so.

153+

154+>>> printSQL (unsafeFunctionN "fun" (true :* false :* localTime *: true))

155+fun(TRUE, FALSE, LOCALTIME, TRUE)

238156-}

239−class KnownNat n => HasParameter

240− (n :: Nat)

241− (schema :: SchemaType)

242− (params :: [NullityType])

243− (ty :: NullityType)

244− | n params -> ty where

245− -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.

246− --

247− -- >>> let expr = parameter @1 int4 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)

248− -- >>> printSQL expr

249− -- ($1 :: int4)

250− parameter

251− :: TypeExpression schema ty

252− -> Expression schema from grouping params ty

253− parameter ty = UnsafeExpression $ parenthesized $

254− "$" <> renderNat @n <+> "::"

255− <+> renderTypeExpression ty

256−instance {-# OVERLAPPING #-} HasParameter 1 schema (ty1:tys) ty1

257−instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) schema params ty)

258− => HasParameter n schema (ty' : params) ty

259−

260−-- | `param` takes a `Nat` using type application and for basic types,

261−-- infers a `TypeExpression`.

262−--

263−-- >>> let expr = param @1 :: Expression sch rels grp '[ 'Null 'PGint4] ('Null 'PGint4)

264−-- >>> printSQL expr

265−-- ($1 :: int4)

266−param

267− :: forall n schema params from grouping ty

268− . (PGTyped schema ty, HasParameter n schema params ty)

269− => Expression schema from grouping params ty -- ^ param

270−param = parameter @n pgtype

271−

272−instance (HasUnique table from columns, Has column columns ty)

273− => IsLabel column (Expression schema from 'Ungrouped params ty) where

274− fromLabel = UnsafeExpression $ renderAlias (Alias @column)

275−instance (HasUnique table from columns, Has column columns ty)

276− => IsLabel column

277− (Aliased (Expression schema from 'Ungrouped params) (column ::: ty)) where

278− fromLabel = fromLabel @column `As` Alias @column

279−instance (HasUnique table from columns, Has column columns ty)

280− => IsLabel column

281− (NP (Aliased (Expression schema from 'Ungrouped params)) '[column ::: ty]) where

282− fromLabel = fromLabel @column :* Nil

283−

284−instance (Has table from columns, Has column columns ty)

285− => IsQualified table column (Expression schema from 'Ungrouped params ty) where

286− table ! column = UnsafeExpression $

287− renderAlias table <> "." <> renderAlias column

288−instance (Has table from columns, Has column columns ty)

289− => IsQualified table column

290− (Aliased (Expression schema from 'Ungrouped params) (column ::: ty)) where

291− table ! column = table ! column `As` column

292−instance (Has table from columns, Has column columns ty)

293− => IsQualified table column

294− (NP (Aliased (Expression schema from 'Ungrouped params)) '[column ::: ty]) where

295− table ! column = table ! column :* Nil

157+type FunctionN xs y

158+ = forall outer commons grp schemas params from

159+ . NP (Expression outer commons grp schemas params from) xs

160+ -- ^ inputs

161+ -> Expression outer commons grp schemas params from y

162+ -- ^ output

163+

164+{- | A @RankNType@ for functions with a variable-length list of

165+homogeneous arguments and at least 1 more argument.

166+-}

167+type FunctionVar x0 x1 y

168+ = forall outer commons grp schemas params from

169+ . [Expression outer commons grp schemas params from x0]

170+ -- ^ inputs

171+ -> Expression outer commons grp schemas params from x1

172+ -- ^ must have at least 1 input

173+ -> Expression outer commons grp schemas params from y

174+ -- ^ output

175+

176+{- | >>> printSQL (unsafeFunctionVar "greatest" [true, null_] false)

177+greatest(TRUE, NULL, FALSE)

178+-}

179+unsafeFunctionVar :: ByteString -> FunctionVar x0 x1 y

180+unsafeFunctionVar fun xs x = UnsafeExpression $ fun <> parenthesized

181+ (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)

182+

183+instance (HasUnique tab (Join outer from) row, Has col row ty)

184+ => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where

185+ fromLabel = UnsafeExpression $ renderSQL (Alias @col)

186+instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])

187+ => IsLabel col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where

188+ fromLabel = fromLabel @col :* Nil

189+instance (HasUnique tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))

190+ => IsLabel col

191+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where

192+ fromLabel = fromLabel @col `As` Alias

193+instance (HasUnique tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])

194+ => IsLabel col

195+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where

196+ fromLabel = fromLabel @col :* Nil

197+

198+instance (Has tab (Join outer from) row, Has col row ty)

199+ => IsQualified tab col (Expression outer commons 'Ungrouped schemas params from ty) where

200+ tab ! col = UnsafeExpression $

201+ renderSQL tab <> "." <> renderSQL col

202+instance (Has tab (Join outer from) row, Has col row ty, tys ~ '[ty])

203+ => IsQualified tab col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where

204+ tab ! col = tab ! col :* Nil

205+instance (Has tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))

206+ => IsQualified tab col

207+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where

208+ tab ! col = tab ! col `As` col

209+instance (Has tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])

210+ => IsQualified tab col

211+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where

212+ tab ! col = tab ! col :* Nil

296213

297214instance

298− ( HasUnique table from columns

299− , Has column columns ty

300− , GroupedBy table column bys

301− ) => IsLabel column

302− (Expression schema from ('Grouped bys) params ty) where

303− fromLabel = UnsafeExpression $ renderAlias (Alias @column)

215+ ( HasUnique tab (Join outer from) row

216+ , Has col row ty

217+ , GroupedBy tab col bys

218+ ) => IsLabel col

219+ (Expression outer commons ('Grouped bys) schemas params from ty) where

220+ fromLabel = UnsafeExpression $ renderSQL (Alias @col)

304221instance

305− ( HasUnique table from columns

306− , Has column columns ty

307− , GroupedBy table column bys

308− ) => IsLabel column

309− ( Aliased (Expression schema from ('Grouped bys) params)

310− (column ::: ty) ) where

311− fromLabel = fromLabel @column `As` Alias @column

222+ ( HasUnique tab (Join outer from) row

223+ , Has col row ty

224+ , GroupedBy tab col bys

225+ , tys ~ '[ty]

226+ ) => IsLabel col

227+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

228+ fromLabel = fromLabel @col :* Nil

312229instance

313− ( HasUnique table from columns

314− , Has column columns ty

315− , GroupedBy table column bys

316− ) => IsLabel column

317− ( NP (Aliased (Expression schema from ('Grouped bys) params))

318− '[column ::: ty] ) where

319− fromLabel = fromLabel @column :* Nil

230+ ( HasUnique tab (Join outer from) row

231+ , Has col row ty

232+ , GroupedBy tab col bys

233+ , column ~ (col ::: ty)

234+ ) => IsLabel col

235+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where

236+ fromLabel = fromLabel @col `As` Alias

237+instance

238+ ( HasUnique tab (Join outer from) row

239+ , Has col row ty

240+ , GroupedBy tab col bys

241+ , columns ~ '[col ::: ty]

242+ ) => IsLabel col

243+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where

244+ fromLabel = fromLabel @col :* Nil

320245

321246instance

322− ( Has table from columns

323− , Has column columns ty

324− , GroupedBy table column bys

325− ) => IsQualified table column

326− (Expression schema from ('Grouped bys) params ty) where

327− table ! column = UnsafeExpression $

328− renderAlias table <> "." <> renderAlias column

247+ ( Has tab (Join outer from) row

248+ , Has col row ty

249+ , GroupedBy tab col bys

250+ ) => IsQualified tab col

251+ (Expression outer commons ('Grouped bys) schemas params from ty) where

252+ tab ! col = UnsafeExpression $

253+ renderSQL tab <> "." <> renderSQL col

329254instance

330− ( Has table from columns

331− , Has column columns ty

332− , GroupedBy table column bys

333− ) => IsQualified table column

334− (Aliased (Expression schema from ('Grouped bys) params)

335− (column ::: ty)) where

336− table ! column = table ! column `As` column

255+ ( Has tab (Join outer from) row

256+ , Has col row ty

257+ , GroupedBy tab col bys

258+ , tys ~ '[ty]

259+ ) => IsQualified tab col

260+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

261+ tab ! col = tab ! col :* Nil

337262instance

338− ( Has table from columns

339− , Has column columns ty

340− , GroupedBy table column bys

341− ) => IsQualified table column

342− ( NP (Aliased (Expression schema from ('Grouped bys) params))

343− '[column ::: ty]) where

344− table ! column = table ! column :* Nil

345−

346−-- | analagous to `Nothing`

347−--

348−-- >>> printSQL null_

349−-- NULL

350−null_ :: Expression schema rels grouping params ('Null ty)

351−null_ = UnsafeExpression "NULL"

352−

353−-- | analagous to `Just`

354−--

355−-- >>> printSQL $ notNull true

356−-- TRUE

357−notNull

358− :: Expression schema rels grouping params ('NotNull ty)

359− -> Expression schema rels grouping params ('Null ty)

360−notNull = UnsafeExpression . renderExpression

361−

362−-- | return the leftmost value which is not NULL

363−--

364−-- >>> printSQL $ coalesce [null_, true] false

365−-- COALESCE(NULL, TRUE, FALSE)

366−coalesce

367− :: [Expression schema from grouping params ('Null ty)]

368− -- ^ @NULL@s may be present

369− -> Expression schema from grouping params ('NotNull ty)

370− -- ^ @NULL@ is absent

371− -> Expression schema from grouping params ('NotNull ty)

372−coalesce nullxs notNullx = UnsafeExpression $

373− "COALESCE" <> parenthesized (commaSeparated

374− ((renderExpression <$> nullxs) <> [renderExpression notNullx]))

375−

376−-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@

377−--

378−-- >>> printSQL $ fromNull true null_

379−-- COALESCE(NULL, TRUE)

380−fromNull

381− :: Expression schema from grouping params ('NotNull ty)

382− -- ^ what to convert @NULL@ to

383− -> Expression schema from grouping params ('Null ty)

384− -> Expression schema from grouping params ('NotNull ty)

385−fromNull notNullx nullx = coalesce [nullx] notNullx

386−

387−-- | >>> printSQL $ null_ & isNull

388−-- NULL IS NULL

389−isNull

390− :: Expression schema from grouping params ('Null ty)

391− -- ^ possibly @NULL@

392− -> Condition schema from grouping params

393−isNull x = UnsafeExpression $ renderExpression x <+> "IS NULL"

394−

395−-- | >>> printSQL $ null_ & isNotNull

396−-- NULL IS NOT NULL

397−isNotNull

398− :: Expression schema from grouping params ('Null ty)

399− -- ^ possibly @NULL@

400− -> Condition schema from grouping params

401−isNotNull x = UnsafeExpression $ renderExpression x <+> "IS NOT NULL"

402−

403−-- | analagous to `maybe` using @IS NULL@

404−--

405−-- >>> printSQL $ matchNull true not_ null_

406−-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END

407−matchNull

408− :: Expression schema from grouping params (nullty)

409− -- ^ what to convert @NULL@ to

410− -> ( Expression schema from grouping params ('NotNull ty)

411− -> Expression schema from grouping params (nullty) )

412− -- ^ function to perform when @NULL@ is absent

413− -> Expression schema from grouping params ('Null ty)

414− -> Expression schema from grouping params (nullty)

415−matchNull y f x = ifThenElse (isNull x) y

416− (f (UnsafeExpression (renderExpression x)))

417−

418−{-| right inverse to `fromNull`, if its arguments are equal then

419−`nullIf` gives @NULL@.

420−

421−>>> :set -XTypeApplications -XDataKinds

422−>>> let expr = nullIf false (param @1) :: Expression schema rels grp '[ 'NotNull 'PGbool] ('Null 'PGbool)

423−>>> printSQL expr

424−NULL IF (FALSE, ($1 :: bool))

425−-}

426−nullIf

427− :: Expression schema from grouping params ('NotNull ty)

428− -- ^ @NULL@ is absent

429− -> Expression schema from grouping params ('NotNull ty)

430− -- ^ @NULL@ is absent

431− -> Expression schema from grouping params ('Null ty)

432−nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized

433− (renderExpression x <> ", " <> renderExpression y)

434−

435−-- | >>> printSQL $ array [null_, false, true]

436−-- ARRAY[NULL, FALSE, TRUE]

437−array

438− :: [Expression schema from grouping params ty]

439− -- ^ array elements

440− -> Expression schema from grouping params (nullity ('PGvararray ty))

441−array xs = UnsafeExpression $

442− "ARRAY[" <> commaSeparated (renderExpression <$> xs) <> "]"

443−

444−-- | >>> printSQL $ array [null_, false, true] & index 2

445−-- (ARRAY[NULL, FALSE, TRUE])[2]

446−index

447− :: Word64 -- ^ index

448− -> Expression schema from grouping params (nullity ('PGvararray ty)) -- ^ array

449− -> Expression schema from grouping params (NullifyType ty)

450−index n expr = UnsafeExpression $

451− parenthesized (renderExpression expr) <> "[" <> fromString (show n) <> "]"

263+ ( Has tab (Join outer from) row

264+ , Has col row ty

265+ , GroupedBy tab col bys

266+ , column ~ (col ::: ty)

267+ ) => IsQualified tab col

268+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where

269+ tab ! col = tab ! col `As` col

270+instance

271+ ( Has tab (Join outer from) row

272+ , Has col row ty

273+ , GroupedBy tab col bys

274+ , columns ~ '[col ::: ty]

275+ ) => IsQualified tab col

276+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where

277+ tab ! col = tab ! col :* Nil

452278

453279instance (KnownSymbol label, label `In` labels) => IsPGlabel label

454− (Expression schema from grouping params (nullity ('PGenum labels))) where

455− label = UnsafeExpression $ renderLabel (PGlabel @label)

456−

457−-- | A row constructor is an expression that builds a row value

458−-- (also called a composite value) using values for its member fields.

459−--

460−-- >>> :{

461−-- type Complex = 'PGcomposite

462−-- '[ "real" ::: 'NotNull 'PGfloat8

463−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

464−-- :}

465−--

466−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression '[] '[] 'Ungrouped '[] ('NotNull Complex)

467−-- >>> printSQL i

468−-- ROW(0, 1)

469−row

470− :: SListI row

471− => NP (Aliased (Expression schema from grouping params)) row

472− -- ^ zero or more expressions for the row field values

473− -> Expression schema from grouping params (nullity ('PGcomposite row))

474−row exprs = UnsafeExpression $ "ROW" <> parenthesized

475− (renderCommaSeparated (\ (expr `As` _) -> renderExpression expr) exprs)

476−

477−-- | >>> :{

478−-- type Complex = 'PGcomposite

479−-- '[ "real" ::: 'NotNull 'PGfloat8

480−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

481−-- :}

482−--

483−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression '["complex" ::: 'Typedef Complex] '[] 'Ungrouped '[] ('NotNull Complex)

484−-- >>> printSQL $ i & field #complex #imaginary

485−-- (ROW(0, 1)::"complex")."imaginary"

486−field

487− :: (Has tydef schema ('Typedef ('PGcomposite row)), Has field row ty)

488− => Alias tydef -- ^ row type

489− -> Alias field -- ^ field name

490− -> Expression schema from grouping params ('NotNull ('PGcomposite row))

491− -> Expression schema from grouping params ty

492−field td fld expr = UnsafeExpression $

493− parenthesized (renderExpression expr <> "::" <> renderAlias td)

494− <> "." <> renderAlias fld

495−

496−instance Semigroup

497− (Expression schema from grouping params (nullity ('PGvararray ty))) where

498− (<>) = unsafeBinaryOp "||"

499−

500−instance Monoid

501− (Expression schema from grouping params (nullity ('PGvararray ty))) where

502− mempty = array []

503− mappend = (<>)

504−

505−-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression sch rels grp '[ 'NotNull 'PGtimestamptz] ('NotNull 'PGtimestamptz)

506−-- >>> printSQL expr

507−-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))

508−greatest

509− :: Expression schema from grouping params (nullty)

510− -- ^ needs at least 1 argument

511− -> [Expression schema from grouping params (nullty)]

512− -- ^ or more

513− -> Expression schema from grouping params (nullty)

514−greatest x xs = UnsafeExpression $ "GREATEST("

515− <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

516−

517−-- | >>> printSQL $ least currentTimestamp [null_]

518−-- LEAST(CURRENT_TIMESTAMP, NULL)

519−least

520− :: Expression schema from grouping params (nullty)

521− -- ^ needs at least 1 argument

522− -> [Expression schema from grouping params (nullty)]

523− -- ^ or more

524− -> Expression schema from grouping params (nullty)

525−least x xs = UnsafeExpression $ "LEAST("

526− <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

280+ (Expression outer commons grp schemas params from (null ('PGenum labels))) where

281+ label = UnsafeExpression $ renderSQL (PGlabel @label)

527282

528283-- | >>> printSQL $ unsafeBinaryOp "OR" true false

529284-- (TRUE OR FALSE)

530−unsafeBinaryOp

531− :: ByteString

532− -- ^ operator

533− -> Expression schema from grouping params (ty0)

534− -> Expression schema from grouping params (ty1)

535− -> Expression schema from grouping params (ty2)

285+unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2

536286unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $

537− renderExpression x <+> op <+> renderExpression y

287+ renderSQL x <+> op <+> renderSQL y

538288

539−-- | >>> printSQL $ unsafeUnaryOp "NOT" true

289+-- | >>> printSQL $ unsafeUnaryOpL "NOT" true

540290-- (NOT TRUE)

541−unsafeUnaryOp

542− :: ByteString

543− -- ^ operator

544− -> Expression schema from grouping params (ty0)

545− -> Expression schema from grouping params (ty1)

546−unsafeUnaryOp op x = UnsafeExpression $ parenthesized $

547− op <+> renderExpression x

291+unsafeUnaryOpL :: ByteString -> x :--> y

292+unsafeUnaryOpL op x = UnsafeExpression $ parenthesized $ op <+> renderSQL x

293+

294+-- | >>> printSQL $ true & unsafeUnaryOpR "IS NOT TRUE"

295+-- (TRUE IS NOT TRUE)

296+unsafeUnaryOpR :: ByteString -> x :--> y

297+unsafeUnaryOpR op x = UnsafeExpression $ parenthesized $ renderSQL x <+> op

548298

549299-- | >>> printSQL $ unsafeFunction "f" true

550300-- f(TRUE)

551−unsafeFunction

552− :: ByteString

553− -- ^ function

554− -> Expression schema from grouping params (xty)

555− -> Expression schema from grouping params (yty)

301+unsafeFunction :: ByteString -> x :--> y

556302unsafeFunction fun x = UnsafeExpression $

557− fun <> parenthesized (renderExpression x)

303+ fun <> parenthesized (renderSQL x)

558304

559−-- | Helper for defining variadic functions.

560−unsafeVariadicFunction

561− :: SListI elems

562− => ByteString

563− -- ^ function

564− -> NP (Expression schema from grouping params) elems

565− -> Expression schema from grouping params ret

566−unsafeVariadicFunction fun x = UnsafeExpression $

567− fun <> parenthesized (commaSeparated (hcollapse (hmap (K . renderExpression) x)))

305+-- | >>> printSQL $ unsafeFunctionN "f" (currentTime :* localTimestamp :* false *: literal 'a')

306+-- f(CURRENT_TIME, LOCALTIMESTAMP, FALSE, E'a')

307+unsafeFunctionN :: SListI xs => ByteString -> FunctionN xs y

308+unsafeFunctionN fun xs = UnsafeExpression $

309+ fun <> parenthesized (renderCommaSeparated renderSQL xs)

568310

569311instance ty `In` PGNum

570− => Num (Expression schema from grouping params (nullity ty)) where

312+ => Num (Expression outer commons grp schemas params from (null ty)) where

571313 (+) = unsafeBinaryOp "+"

572314 (-) = unsafeBinaryOp "-"

573315 (*) = unsafeBinaryOp "*"

@@ -579,18 +321,23 @@ instance ty `In` PGNum

579321 . show

580322

581323instance (ty `In` PGNum, ty `In` PGFloating) => Fractional

582− (Expression schema from grouping params (nullity ty)) where

324+ (Expression outer commons grp schemas params from (null ty)) where

583325 (/) = unsafeBinaryOp "/"

584− fromRational x = fromInteger (numerator x) / fromInteger (denominator x)

326+ fromRational

327+ = UnsafeExpression

328+ . fromString

329+ . ($ "")

330+ . showFFloat Nothing

331+ . fromRat @Double

585332

586333instance (ty `In` PGNum, ty `In` PGFloating) => Floating

587− (Expression schema from grouping params (nullity ty)) where

334+ (Expression outer commons grp schemas params from (null ty)) where

588335 pi = UnsafeExpression "pi()"

589336 exp = unsafeFunction "exp"

590337 log = unsafeFunction "ln"

591338 sqrt = unsafeFunction "sqrt"

592339 b ** x = UnsafeExpression $

593− "power(" <> renderExpression b <> ", " <> renderExpression x <> ")"

340+ "power(" <> renderSQL b <> ", " <> renderSQL x <> ")"

594341 logBase b y = log y / log b

595342 sin = unsafeFunction "sin"

596343 cos = unsafeFunction "cos"

@@ -605,1154 +352,47 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating

605352 acosh x = log (x + sqrt (x*x - 1))

606353 atanh x = log ((1 + x) / (1 - x)) / 2

607354

608−-- | >>> :{

609−-- let

610−-- expression :: Expression schema from grouping params (nullity 'PGfloat4)

611−-- expression = atan2_ pi 2

612−-- in printSQL expression

613−-- :}

614−-- atan2(pi(), 2)

615−atan2_

616− :: float `In` PGFloating

617− => Expression schema from grouping params (nullity float)

618− -- ^ numerator

619− -> Expression schema from grouping params (nullity float)

620− -- ^ denominator

621− -> Expression schema from grouping params (nullity float)

622−atan2_ y x = UnsafeExpression $

623− "atan2(" <> renderExpression y <> ", " <> renderExpression x <> ")"

624−

625−-- When a `cast` is applied to an `Expression` of a known type, it

626−-- represents a run-time type conversion. The cast will succeed only if a

627−-- suitable type conversion operation has been defined.

628−--

629−-- | >>> printSQL $ true & cast int4

630−-- (TRUE :: int4)

631−cast

632− :: TypeExpression schema ty1

633− -- ^ type to cast as

634− -> Expression schema from grouping params ty0

635− -- ^ value to convert

636− -> Expression schema from grouping params ty1

637−cast ty x = UnsafeExpression $ parenthesized $

638− renderExpression x <+> "::" <+> renderTypeExpression ty

639−

640−-- | integer division, truncates the result

641−--

642−-- >>> :{

643−-- let

644−-- expression :: Expression schema from grouping params (nullity 'PGint2)

645−-- expression = 5 `quot_` 2

646−-- in printSQL expression

647−-- :}

648−-- (5 / 2)

649−quot_

650− :: int `In` PGIntegral

651− => Expression schema from grouping params (nullity int)

652− -- ^ numerator

653− -> Expression schema from grouping params (nullity int)

654− -- ^ denominator

655− -> Expression schema from grouping params (nullity int)

656−quot_ = unsafeBinaryOp "/"

657−

658−-- | remainder upon integer division

659−--

660−-- >>> :{

661−-- let

662−-- expression :: Expression schema from grouping params (nullity 'PGint2)

663−-- expression = 5 `rem_` 2

664−-- in printSQL expression

665−-- :}

666−-- (5 % 2)

667−rem_

668− :: int `In` PGIntegral

669− => Expression schema from grouping params (nullity int)

670− -- ^ numerator

671− -> Expression schema from grouping params (nullity int)

672− -- ^ denominator

673− -> Expression schema from grouping params (nullity int)

674−rem_ = unsafeBinaryOp "%"

675−

676−-- | >>> :{

677−-- let

678−-- expression :: Expression schema from grouping params (nullity 'PGfloat4)

679−-- expression = trunc pi

680−-- in printSQL expression

681−-- :}

682−-- trunc(pi())

683−trunc

684− :: frac `In` PGFloating

685− => Expression schema from grouping params (nullity frac)

686− -- ^ fractional number

687− -> Expression schema from grouping params (nullity frac)

688−trunc = unsafeFunction "trunc"

689−

690−-- | >>> :{

691−-- let

692−-- expression :: Expression schema from grouping params (nullity 'PGfloat4)

693−-- expression = round_ pi

694−-- in printSQL expression

695−-- :}

696−-- round(pi())

697−round_

698− :: frac `In` PGFloating

699− => Expression schema from grouping params (nullity frac)

700− -- ^ fractional number

701− -> Expression schema from grouping params (nullity frac)

702−round_ = unsafeFunction "round"

703−

704−-- | >>> :{

705−-- let

706−-- expression :: Expression schema from grouping params (nullity 'PGfloat4)

707−-- expression = ceiling_ pi

708−-- in printSQL expression

709−-- :}

710−-- ceiling(pi())

711−ceiling_

712− :: frac `In` PGFloating

713− => Expression schema from grouping params (nullity frac)

714− -- ^ fractional number

715− -> Expression schema from grouping params (nullity frac)

716−ceiling_ = unsafeFunction "ceiling"

717−

718−-- | A `Condition` is an `Expression`, which can evaluate

719−-- to `true`, `false` or `null_`. This is because SQL uses

720−-- a three valued logic.

721−type Condition schema from grouping params =

722− Expression schema from grouping params ('Null 'PGbool)

723−

724−-- | >>> printSQL true

725−-- TRUE

726−true :: Expression schema from grouping params (nullity 'PGbool)

727−true = UnsafeExpression "TRUE"

728−

729−-- | >>> printSQL false

730−-- FALSE

731−false :: Expression schema from grouping params (nullity 'PGbool)

732−false = UnsafeExpression "FALSE"

733−

734−-- | >>> printSQL $ not_ true

735−-- (NOT TRUE)

736−not_

737− :: Expression schema from grouping params (nullity 'PGbool)

738− -> Expression schema from grouping params (nullity 'PGbool)

739−not_ = unsafeUnaryOp "NOT"

740−

741−-- | >>> printSQL $ true .&& false

742−-- (TRUE AND FALSE)

743−(.&&)

744− :: Expression schema from grouping params (nullity 'PGbool)

745− -> Expression schema from grouping params (nullity 'PGbool)

746− -> Expression schema from grouping params (nullity 'PGbool)

747−infixr 3 .&&

748−(.&&) = unsafeBinaryOp "AND"

749−

750−-- | >>> printSQL $ true .|| false

751−-- (TRUE OR FALSE)

752−(.||)

753− :: Expression schema from grouping params (nullity 'PGbool)

754− -> Expression schema from grouping params (nullity 'PGbool)

755− -> Expression schema from grouping params (nullity 'PGbool)

756−infixr 2 .||

757−(.||) = unsafeBinaryOp "OR"

758−

759−-- | >>> :{

760−-- let

761−-- expression :: Expression schema from grouping params (nullity 'PGint2)

762−-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3

763−-- in printSQL expression

764−-- :}

765−-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END

766−caseWhenThenElse

767− :: [ ( Condition schema from grouping params

768− , Expression schema from grouping params ty

769− ) ]

770− -- ^ whens and thens

771− -> Expression schema from grouping params ty

772− -- ^ else

773− -> Expression schema from grouping params ty

774−caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat

775− [ "CASE"

776− , mconcat

777− [ mconcat

778− [ " WHEN ", renderExpression when_

779− , " THEN ", renderExpression then_

780− ]

781− | (when_,then_) <- whenThens

782− ]

783− , " ELSE ", renderExpression else_

784− , " END"

785− ]

786−

787−-- | >>> :{

788−-- let

789−-- expression :: Expression schema from grouping params (nullity 'PGint2)

790−-- expression = ifThenElse true 1 0

791−-- in printSQL expression

792−-- :}

793−-- CASE WHEN TRUE THEN 1 ELSE 0 END

794−ifThenElse

795− :: Condition schema from grouping params

796− -> Expression schema from grouping params ty -- ^ then

797− -> Expression schema from grouping params ty -- ^ else

798− -> Expression schema from grouping params ty

799−ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_

800−

801−-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`

802−-- will produce @NULL@s if one of their arguments is @NULL@.

803−--

804−-- >>> printSQL $ true .== null_

805−-- (TRUE = NULL)

806−(.==)

807− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

808− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

809− -> Condition schema from grouping params

810−(.==) = unsafeBinaryOp "="

811−infix 4 .==

812−

813−-- | >>> printSQL $ true ./= null_

814−-- (TRUE <> NULL)

815−(./=)

816− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

817− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

818− -> Condition schema from grouping params

819−(./=) = unsafeBinaryOp "<>"

820−infix 4 ./=

821−

822−-- | >>> printSQL $ true .>= null_

823−-- (TRUE >= NULL)

824−(.>=)

825− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

826− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

827− -> Condition schema from grouping params

828−(.>=) = unsafeBinaryOp ">="

829−infix 4 .>=

830−

831−-- | >>> printSQL $ true .< null_

832−-- (TRUE < NULL)

833−(.<)

834− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

835− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

836− -> Condition schema from grouping params

837−(.<) = unsafeBinaryOp "<"

838−infix 4 .<

839−

840−-- | >>> printSQL $ true .<= null_

841−-- (TRUE <= NULL)

842−(.<=)

843− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

844− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

845− -> Condition schema from grouping params

846−(.<=) = unsafeBinaryOp "<="

847−infix 4 .<=

848−

849−-- | >>> printSQL $ true .> null_

850−-- (TRUE > NULL)

851−(.>)

852− :: Expression schema from grouping params (nullity0 ty) -- ^ lhs

853− -> Expression schema from grouping params (nullity1 ty) -- ^ rhs

854− -> Condition schema from grouping params

855−(.>) = unsafeBinaryOp ">"

856−infix 4 .>

857−

858−-- | >>> printSQL currentDate

859−-- CURRENT_DATE

860−currentDate

861− :: Expression schema from grouping params (nullity 'PGdate)

862−currentDate = UnsafeExpression "CURRENT_DATE"

863−

864−-- | >>> printSQL currentTime

865−-- CURRENT_TIME

866−currentTime

867− :: Expression schema from grouping params (nullity 'PGtimetz)

868−currentTime = UnsafeExpression "CURRENT_TIME"

869−

870−-- | >>> printSQL currentTimestamp

871−-- CURRENT_TIMESTAMP

872−currentTimestamp

873− :: Expression schema from grouping params (nullity 'PGtimestamptz)

874−currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

875−

876−-- | >>> printSQL localTime

877−-- LOCALTIME

878−localTime

879− :: Expression schema from grouping params (nullity 'PGtime)

880−localTime = UnsafeExpression "LOCALTIME"

881−

882−-- | >>> printSQL localTimestamp

883−-- LOCALTIMESTAMP

884−localTimestamp

885− :: Expression schema from grouping params (nullity 'PGtimestamp)

886−localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

887−

888−{-----------------------------------------

889−text

890−-----------------------------------------}

355+-- | Contained by operators

356+class PGSubset container where

357+ (@>) :: Operator (null0 container) (null1 container) ('Null 'PGbool)

358+ (@>) = unsafeBinaryOp "@>"

359+ (<@) :: Operator (null0 container) (null1 container) ('Null 'PGbool)

360+ (<@) = unsafeBinaryOp "<@"

361+instance PGSubset 'PGjsonb

362+instance PGSubset 'PGtsquery

363+instance PGSubset ('PGvararray ty)

891364

892365instance IsString

893− (Expression schema from grouping params (nullity 'PGtext)) where

366+ (Expression outer commons grp schemas params from (null 'PGtext)) where

894367 fromString str = UnsafeExpression $

895368 "E\'" <> fromString (escape =<< str) <> "\'"

896− where

897− escape = \case

898− '\NUL' -> "\\0"

899− '\'' -> "''"

900− '"' -> "\\\""

901− '\b' -> "\\b"

902− '\n' -> "\\n"

903− '\r' -> "\\r"

904− '\t' -> "\\t"

905− '\\' -> "\\\\"

906− c -> [c]

369+instance IsString

370+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

371+ fromString str = UnsafeExpression . parenthesized . (<> " :: tsvector") $

372+ "E\'" <> fromString (escape =<< str) <> "\'"

373+instance IsString

374+ (Expression outer commons grp schemas params from (null 'PGtsquery)) where

375+ fromString str = UnsafeExpression . parenthesized . (<> " :: tsquery") $

376+ "E\'" <> fromString (escape =<< str) <> "\'"

907377

908378instance Semigroup

909− (Expression schema from grouping params (nullity 'PGtext)) where

379+ (Expression outer commons grp schemas params from (null ('PGvararray ty))) where

380+ (<>) = unsafeBinaryOp "||"

381+instance Semigroup

382+ (Expression outer commons grp schemas params from (null 'PGjsonb)) where

383+ (<>) = unsafeBinaryOp "||"

384+instance Semigroup

385+ (Expression outer commons grp schemas params from (null 'PGtext)) where

386+ (<>) = unsafeBinaryOp "||"

387+instance Semigroup

388+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

910389 (<>) = unsafeBinaryOp "||"

911390

912391instance Monoid

913− (Expression schema from grouping params (nullity 'PGtext)) where

392+ (Expression outer commons grp schemas params from (null 'PGtext)) where

393+ mempty = fromString ""

394+ mappend = (<>)

395+instance Monoid

396+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

914397 mempty = fromString ""

915398 mappend = (<>)

916−

917−-- | >>> printSQL $ lower "ARRRGGG"

918−-- lower(E'ARRRGGG')

919−lower

920− :: Expression schema from grouping params (nullity 'PGtext)

921− -- ^ string to lower case

922− -> Expression schema from grouping params (nullity 'PGtext)

923−lower = unsafeFunction "lower"

924−

925−-- | >>> printSQL $ upper "eeee"

926−-- upper(E'eeee')

927−upper

928− :: Expression schema from grouping params (nullity 'PGtext)

929− -- ^ string to upper case

930− -> Expression schema from grouping params (nullity 'PGtext)

931−upper = unsafeFunction "upper"

932−

933−-- | >>> printSQL $ charLength "four"

934−-- char_length(E'four')

935−charLength

936− :: Expression schema from grouping params (nullity 'PGtext)

937− -- ^ string to measure

938− -> Expression schema from grouping params (nullity 'PGint4)

939−charLength = unsafeFunction "char_length"

940−

941−-- | The `like` expression returns true if the @string@ matches

942−-- the supplied @pattern@. If @pattern@ does not contain percent signs

943−-- or underscores, then the pattern only represents the string itself;

944−-- in that case `like` acts like the equals operator. An underscore (_)

945−-- in pattern stands for (matches) any single character; a percent sign (%)

946−-- matches any sequence of zero or more characters.

947−--

948−-- >>> printSQL $ "abc" `like` "a%"

949−-- (E'abc' LIKE E'a%')

950−like

951− :: Expression schema from grouping params (nullity 'PGtext)

952− -- ^ string

953− -> Expression schema from grouping params (nullity 'PGtext)

954− -- ^ pattern

955− -> Expression schema from grouping params (nullity 'PGbool)

956−like = unsafeBinaryOp "LIKE"

957−

958−{-----------------------------------------

959− -- json and jsonb support

960−

961−See https://www.postgresql.org/docs/10/static/functions-json.html -- most

962−comments lifted directly from this page.

963−

964−Table 9.44: json and jsonb operators

965−-----------------------------------------}

966−

967−-- | Get JSON value (object field or array element) at a key.

968−(.->)

969− :: (json `In` PGJsonType, key `In` PGJsonKey)

970− => Expression schema from grouping params (nullity json)

971− -> Expression schema from grouping params (nullity key)

972− -> Expression schema from grouping params ('Null json)

973−infixl 8 .->

974−(.->) = unsafeBinaryOp "->"

975−

976−-- | Get JSON value (object field or array element) at a key, as text.

977−(.->>)

978− :: (json `In` PGJsonType, key `In` PGJsonKey)

979− => Expression schema from grouping params (nullity json)

980− -> Expression schema from grouping params (nullity key)

981− -> Expression schema from grouping params ('Null 'PGtext)

982−infixl 8 .->>

983−(.->>) = unsafeBinaryOp "->>"

984−

985−-- | Get JSON value at a specified path.

986−(.#>)

987− :: (json `In` PGJsonType, PGTextArray "(.#>)" path)

988− => Expression schema from grouping params (nullity json)

989− -> Expression schema from grouping params (nullity path)

990− -> Expression schema from grouping params ('Null json)

991−infixl 8 .#>

992−(.#>) = unsafeBinaryOp "#>"

993−

994−-- | Get JSON value at a specified path as text.

995−(.#>>)

996− :: (json `In` PGJsonType, PGTextArray "(.#>>)" path)

997− => Expression schema from grouping params (nullity json)

998− -> Expression schema from grouping params (nullity path)

999− -> Expression schema from grouping params ('Null 'PGtext)

1000−infixl 8 .#>>

1001−(.#>>) = unsafeBinaryOp "#>>"

1002−

1003−-- Additional jsonb operators

1004−

1005−-- | Does the left JSON value contain the right JSON path/value entries at the

1006−-- top level?

1007−(.@>)

1008− :: Expression schema from grouping params (nullity 'PGjsonb)

1009− -> Expression schema from grouping params (nullity 'PGjsonb)

1010− -> Condition schema from grouping params

1011−infixl 9 .@>

1012−(.@>) = unsafeBinaryOp "@>"

1013−

1014−-- | Are the left JSON path/value entries contained at the top level within the

1015−-- right JSON value?

1016−(.<@)

1017− :: Expression schema from grouping params (nullity 'PGjsonb)

1018− -> Expression schema from grouping params (nullity 'PGjsonb)

1019− -> Condition schema from grouping params

1020−infixl 9 .<@

1021−(.<@) = unsafeBinaryOp "<@"

1022−

1023−-- | Does the string exist as a top-level key within the JSON value?

1024−(.?)

1025− :: Expression schema from grouping params (nullity 'PGjsonb)

1026− -> Expression schema from grouping params (nullity 'PGtext)

1027− -> Condition schema from grouping params

1028−infixl 9 .?

1029−(.?) = unsafeBinaryOp "?"

1030−

1031−-- | Do any of these array strings exist as top-level keys?

1032−(.?|)

1033− :: Expression schema from grouping params (nullity 'PGjsonb)

1034− -> Expression schema from grouping params (nullity ('PGvararray ('NotNull 'PGtext)))

1035− -> Condition schema from grouping params

1036−infixl 9 .?|

1037−(.?|) = unsafeBinaryOp "?|"

1038−

1039−-- | Do all of these array strings exist as top-level keys?

1040−(.?&)

1041− :: Expression schema from grouping params (nullity 'PGjsonb)

1042− -> Expression schema from grouping params (nullity ('PGvararray ('NotNull 'PGtext)))

1043− -> Condition schema from grouping params

1044−infixl 9 .?&

1045−(.?&) = unsafeBinaryOp "?&"

1046−

1047−-- | Concatenate two jsonb values into a new jsonb value.

1048−instance

1049− Semigroup (Expression schema from grouping param (nullity 'PGjsonb)) where

1050− (<>) = unsafeBinaryOp "||"

1051−

1052−-- | Delete a key or keys from a JSON object, or remove an array element.

1053−--

1054−-- If the right operand is..

1055−--

1056−-- @ text @: Delete key/value pair or string element from left operand. Key/value pairs

1057−-- are matched based on their key value.

1058−--

1059−-- @ text[] @: Delete multiple key/value pairs or string elements

1060−-- from left operand. Key/value pairs are matched based on their key value.

1061−--

1062−-- @ integer @: Delete the array element with specified index (Negative integers

1063−-- count from the end). Throws an error if top level container is not an array.

1064−(.-.)

1065− :: (key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]) -- hlint error without parens here

1066− => Expression schema from grouping params (nullity 'PGjsonb)

1067− -> Expression schema from grouping params (nullity key)

1068− -> Expression schema from grouping params (nullity 'PGjsonb)

1069−infixl 6 .-.

1070−(.-.) = unsafeBinaryOp "-"

1071−

1072−-- | Delete the field or element with specified path (for JSON arrays, negative

1073−-- integers count from the end)

1074−(#-.)

1075− :: PGTextArray "(#-.)" arrayty

1076− => Expression schema from grouping params (nullity 'PGjsonb)

1077− -> Expression schema from grouping params (nullity arrayty)

1078− -> Expression schema from grouping params (nullity 'PGjsonb)

1079−infixl 6 #-.

1080−(#-.) = unsafeBinaryOp "#-"

1081−

1082−{-----------------------------------------

1083−Table 9.45: JSON creation functions

1084−-----------------------------------------}

1085−

1086−-- | Literal binary JSON

1087−jsonbLit

1088− :: JSON.ToJSON x

1089− => x -> Expression schema from grouping params (nullity 'PGjsonb)

1090−jsonbLit = cast jsonb . UnsafeExpression

1091− . singleQuotedUtf8 . toStrict . JSON.encode

1092−

1093−-- | Literal JSON

1094−jsonLit

1095− :: JSON.ToJSON x

1096− => x -> Expression schema from grouping params (nullity 'PGjson)

1097−jsonLit = cast json . UnsafeExpression

1098− . singleQuotedUtf8 . toStrict . JSON.encode

1099−

1100−-- | Returns the value as json. Arrays and composites are converted

1101−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

1102−-- type to json, the cast function will be used to perform the conversion;

1103−-- otherwise, a scalar value is produced. For any scalar type other than a

1104−-- number, a Boolean, or a null value, the text representation will be used, in

1105−-- such a fashion that it is a valid json value.

1106−toJson

1107− :: Expression schema from grouping params (nullity ty)

1108− -> Expression schema from grouping params (nullity 'PGjson)

1109−toJson = unsafeFunction "to_json"

1110−

1111−-- | Returns the value as jsonb. Arrays and composites are converted

1112−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

1113−-- type to json, the cast function will be used to perform the conversion;

1114−-- otherwise, a scalar value is produced. For any scalar type other than a

1115−-- number, a Boolean, or a null value, the text representation will be used, in

1116−-- such a fashion that it is a valid jsonb value.

1117−toJsonb

1118− :: Expression schema from grouping params (nullity ty)

1119− -> Expression schema from grouping params (nullity 'PGjsonb)

1120−toJsonb = unsafeFunction "to_jsonb"

1121−

1122−-- | Returns the array as a JSON array. A PostgreSQL multidimensional array

1123−-- becomes a JSON array of arrays.

1124−arrayToJson

1125− :: PGArray "arrayToJson" arr

1126− => Expression schema from grouping params (nullity arr)

1127− -> Expression schema from grouping params (nullity 'PGjson)

1128−arrayToJson = unsafeFunction "array_to_json"

1129−

1130−-- | Returns the row as a JSON object.

1131−rowToJson

1132− :: Expression schema from grouping params (nullity ('PGcomposite ty))

1133− -> Expression schema from grouping params (nullity 'PGjson)

1134−rowToJson = unsafeFunction "row_to_json"

1135−

1136−-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic

1137−-- argument list.

1138−jsonBuildArray

1139− :: SListI elems

1140− => NP (Expression schema from grouping params) elems

1141− -> Expression schema from grouping params (nullity 'PGjson)

1142−jsonBuildArray = unsafeVariadicFunction "json_build_array"

1143−

1144−-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a

1145−-- variadic argument list.

1146−jsonbBuildArray

1147− :: SListI elems

1148− => NP (Expression schema from grouping params) elems

1149− -> Expression schema from grouping params (nullity 'PGjsonb)

1150−jsonbBuildArray = unsafeVariadicFunction "jsonb_build_array"

1151−

1152−unsafeRowFunction

1153− :: All Top elems

1154− => NP (Aliased (Expression schema from grouping params)) elems

1155− -> [ByteString]

1156−unsafeRowFunction =

1157− (`appEndo` []) . hcfoldMap (Proxy :: Proxy Top)

1158− (\(col `As` name) -> Endo $ \xs ->

1159− renderAliasString name : renderExpression col : xs)

1160−

1161−-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic

1162−-- argument list. The elements of the argument list must alternate between text

1163−-- and values.

1164−jsonBuildObject

1165− :: All Top elems

1166− => NP (Aliased (Expression schema from grouping params)) elems

1167− -> Expression schema from grouping params (nullity 'PGjson)

1168−jsonBuildObject

1169− = unsafeFunction "json_build_object"

1170− . UnsafeExpression

1171− . commaSeparated

1172− . unsafeRowFunction

1173−

1174−-- | Builds a possibly-heterogeneously-typed (binary) JSON object out of a

1175−-- variadic argument list. The elements of the argument list must alternate

1176−-- between text and values.

1177−jsonbBuildObject

1178− :: All Top elems

1179− => NP (Aliased (Expression schema from grouping params)) elems

1180− -> Expression schema from grouping params (nullity 'PGjsonb)

1181−jsonbBuildObject

1182− = unsafeFunction "jsonb_build_object"

1183− . UnsafeExpression

1184− . commaSeparated

1185− . unsafeRowFunction

1186−

1187−-- | Builds a JSON object out of a text array. The array must have either

1188−-- exactly one dimension with an even number of members, in which case they are

1189−-- taken as alternating key/value pairs, or two dimensions such that each inner

1190−-- array has exactly two elements, which are taken as a key/value pair.

1191−jsonObject

1192− :: PGArrayOf "jsonObject" arr ('NotNull 'PGtext)

1193− => Expression schema from grouping params (nullity arr)

1194− -> Expression schema from grouping params (nullity 'PGjson)

1195−jsonObject = unsafeFunction "json_object"

1196−

1197−-- | Builds a binary JSON object out of a text array. The array must have either

1198−-- exactly one dimension with an even number of members, in which case they are

1199−-- taken as alternating key/value pairs, or two dimensions such that each inner

1200−-- array has exactly two elements, which are taken as a key/value pair.

1201−jsonbObject

1202− :: PGArrayOf "jsonbObject" arr ('NotNull 'PGtext)

1203− => Expression schema from grouping params (nullity arr)

1204− -> Expression schema from grouping params (nullity 'PGjsonb)

1205−jsonbObject = unsafeFunction "jsonb_object"

1206−

1207−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

1208−-- keys and one for values, that are zipped pairwise to create a JSON object.

1209−jsonZipObject

1210− :: ( PGArrayOf "jsonZipObject" keysArray ('NotNull 'PGtext)

1211− , PGArrayOf "jsonZipObject" valuesArray ('NotNull 'PGtext))

1212− => Expression schema from grouping params (nullity keysArray)

1213− -> Expression schema from grouping params (nullity valuesArray)

1214− -> Expression schema from grouping params (nullity 'PGjson)

1215−jsonZipObject ks vs =

1216− unsafeVariadicFunction "json_object" (ks :* vs :* Nil)

1217−

1218−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

1219−-- keys and one for values, that are zipped pairwise to create a binary JSON

1220−-- object.

1221−jsonbZipObject

1222− :: ( PGArrayOf "jsonbZipObject" keysArray ('NotNull 'PGtext)

1223− , PGArrayOf "jsonbZipObject" valuesArray ('NotNull 'PGtext))

1224− => Expression schema from grouping params (nullity keysArray)

1225− -> Expression schema from grouping params (nullity valuesArray)

1226− -> Expression schema from grouping params (nullity 'PGjsonb)

1227−jsonbZipObject ks vs =

1228− unsafeVariadicFunction "jsonb_object" (ks :* vs :* Nil)

1229−

1230−{-----------------------------------------

1231−Table 9.46: JSON processing functions

1232−-----------------------------------------}

1233−

1234−-- | Returns the number of elements in the outermost JSON array.

1235−jsonArrayLength

1236− :: Expression schema from grouping params (nullity 'PGjson)

1237− -> Expression schema from grouping params (nullity 'PGint4)

1238−jsonArrayLength = unsafeFunction "json_array_length"

1239−

1240−-- | Returns the number of elements in the outermost binary JSON array.

1241−jsonbArrayLength

1242− :: Expression schema from grouping params (nullity 'PGjsonb)

1243− -> Expression schema from grouping params (nullity 'PGint4)

1244−jsonbArrayLength = unsafeFunction "jsonb_array_length"

1245−

1246−-- | Returns JSON value pointed to by the given path (equivalent to #>

1247−-- operator).

1248−jsonExtractPath

1249− :: SListI elems

1250− => Expression schema from grouping params (nullity 'PGjson)

1251− -> NP (Expression schema from grouping params) elems

1252− -> Expression schema from grouping params (nullity 'PGjsonb)

1253−jsonExtractPath x xs =

1254− unsafeVariadicFunction "json_extract_path" (x :* xs)

1255−

1256−-- | Returns JSON value pointed to by the given path (equivalent to #>

1257−-- operator).

1258−jsonbExtractPath

1259− :: SListI elems

1260− => Expression schema from grouping params (nullity 'PGjsonb)

1261− -> NP (Expression schema from grouping params) elems

1262− -> Expression schema from grouping params (nullity 'PGjsonb)

1263−jsonbExtractPath x xs =

1264− unsafeVariadicFunction "jsonb_extract_path" (x :* xs)

1265−

1266−-- | Returns JSON value pointed to by the given path (equivalent to #>

1267−-- operator), as text.

1268−jsonExtractPathAsText

1269− :: SListI elems

1270− => Expression schema from grouping params (nullity 'PGjson)

1271− -> NP (Expression schema from grouping params) elems

1272− -> Expression schema from grouping params (nullity 'PGjson)

1273−jsonExtractPathAsText x xs =

1274− unsafeVariadicFunction "json_extract_path_text" (x :* xs)

1275−

1276−-- | Returns JSON value pointed to by the given path (equivalent to #>

1277−-- operator), as text.

1278−jsonbExtractPathAsText

1279− :: SListI elems

1280− => Expression schema from grouping params (nullity 'PGjsonb)

1281− -> NP (Expression schema from grouping params) elems

1282− -> Expression schema from grouping params (nullity 'PGjsonb)

1283−jsonbExtractPathAsText x xs =

1284− unsafeVariadicFunction "jsonb_extract_path_text" (x :* xs)

1285−

1286−-- | Returns the type of the outermost JSON value as a text string. Possible

1287−-- types are object, array, string, number, boolean, and null.

1288−jsonTypeof

1289− :: Expression schema from grouping params (nullity 'PGjson)

1290− -> Expression schema from grouping params (nullity 'PGtext)

1291−jsonTypeof = unsafeFunction "json_typeof"

1292−

1293−-- | Returns the type of the outermost binary JSON value as a text string.

1294−-- Possible types are object, array, string, number, boolean, and null.

1295−jsonbTypeof

1296− :: Expression schema from grouping params (nullity 'PGjsonb)

1297− -> Expression schema from grouping params (nullity 'PGtext)

1298−jsonbTypeof = unsafeFunction "jsonb_typeof"

1299−

1300−-- | Returns its argument with all object fields that have null values omitted.

1301−-- Other null values are untouched.

1302−jsonStripNulls

1303− :: Expression schema from grouping params (nullity 'PGjson)

1304− -> Expression schema from grouping params (nullity 'PGjson)

1305−jsonStripNulls = unsafeFunction "json_strip_nulls"

1306−

1307−-- | Returns its argument with all object fields that have null values omitted.

1308−-- Other null values are untouched.

1309−jsonbStripNulls

1310− :: Expression schema from grouping params (nullity 'PGjsonb)

1311− -> Expression schema from grouping params (nullity 'PGjsonb)

1312−jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"

1313−

1314−-- | @ jsonbSet target path new_value create_missing @

1315−--

1316−-- Returns target with the section designated by path replaced by new_value,

1317−-- or with new_value added if create_missing is true ( default is true) and the

1318−-- item designated by path does not exist. As with the path orientated

1319−-- operators, negative integers that appear in path count from the end of JSON

1320−-- arrays.

1321−jsonbSet

1322− :: PGTextArray "jsonbSet" arr

1323− => Expression schema from grouping params (nullity 'PGjsonb)

1324− -> Expression schema from grouping params (nullity arr)

1325− -> Expression schema from grouping params (nullity 'PGjsonb)

1326− -> Maybe (Expression schema from grouping params (nullity 'PGbool))

1327− -> Expression schema from grouping params (nullity 'PGjsonb)

1328−jsonbSet tgt path val createMissing = case createMissing of

1329− Just m -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* m :* Nil)

1330− Nothing -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* Nil)

1331−

1332−-- | @ jsonbInsert target path new_value insert_after @

1333−--

1334−-- Returns target with new_value inserted. If target section designated by

1335−-- path is in a JSONB array, new_value will be inserted before target or after

1336−-- if insert_after is true (default is false). If target section designated by

1337−-- path is in JSONB object, new_value will be inserted only if target does not

1338−-- exist. As with the path orientated operators, negative integers that appear

1339−-- in path count from the end of JSON arrays.

1340−jsonbInsert

1341− :: PGTextArray "jsonbInsert" arr

1342− => Expression schema from grouping params (nullity 'PGjsonb)

1343− -> Expression schema from grouping params (nullity arr)

1344− -> Expression schema from grouping params (nullity 'PGjsonb)

1345− -> Maybe (Expression schema from grouping params (nullity 'PGbool))

1346− -> Expression schema from grouping params (nullity 'PGjsonb)

1347−jsonbInsert tgt path val insertAfter = case insertAfter of

1348− Just i -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* i :* Nil)

1349− Nothing -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* Nil)

1350−

1351−-- | Returns its argument as indented JSON text.

1352−jsonbPretty

1353− :: Expression schema from grouping params (nullity 'PGjsonb)

1354− -> Expression schema from grouping params (nullity 'PGtext)

1355−jsonbPretty = unsafeFunction "jsonb_pretty"

1356−

1357−{-----------------------------------------

1358−aggregation

1359−-----------------------------------------}

1360−

1361−-- | escape hatch to define aggregate functions

1362−unsafeAggregate

1363− :: ByteString -- ^ aggregate function

1364− -> Expression schema from 'Ungrouped params (xty)

1365− -> Expression schema from ('Grouped bys) params (yty)

1366−unsafeAggregate fun x = UnsafeExpression $ mconcat

1367− [fun, "(", renderExpression x, ")"]

1368−

1369−-- | escape hatch to define aggregate functions over distinct values

1370−unsafeAggregateDistinct

1371− :: ByteString -- ^ aggregate function

1372− -> Expression schema from 'Ungrouped params (xty)

1373− -> Expression schema from ('Grouped bys) params (yty)

1374−unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat

1375− [fun, "(DISTINCT ", renderExpression x, ")"]

1376−

1377−-- | >>> :{

1378−-- let

1379−-- expression :: Expression schema '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Grouped bys) params ('Null 'PGnumeric)

1380−-- expression = sum_ #col

1381−-- in printSQL expression

1382−-- :}

1383−-- sum("col")

1384−sum_

1385− :: ty `In` PGNum

1386− => Expression schema from 'Ungrouped params (nullity ty)

1387− -- ^ what to sum

1388− -> Expression schema from ('Grouped bys) params (nullity ty)

1389−sum_ = unsafeAggregate "sum"

1390−

1391−-- | >>> :{

1392−-- let

1393−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGnumeric]] ('Grouped bys) params (nullity 'PGnumeric)

1394−-- expression = sumDistinct #col

1395−-- in printSQL expression

1396−-- :}

1397−-- sum(DISTINCT "col")

1398−sumDistinct

1399− :: ty `In` PGNum

1400− => Expression schema from 'Ungrouped params (nullity ty)

1401− -- ^ what to sum

1402− -> Expression schema from ('Grouped bys) params (nullity ty)

1403−sumDistinct = unsafeAggregateDistinct "sum"

1404−

1405−-- | A constraint for `PGType`s that you can take averages of and the resulting

1406−-- `PGType`.

1407−class PGAvg ty avg | ty -> avg where

1408− avg, avgDistinct

1409− :: Expression schema from 'Ungrouped params (nullity ty)

1410− -- ^ what to average

1411− -> Expression schema from ('Grouped bys) params (nullity avg)

1412− avg = unsafeAggregate "avg"

1413− avgDistinct = unsafeAggregateDistinct "avg"

1414−instance PGAvg 'PGint2 'PGnumeric

1415−instance PGAvg 'PGint4 'PGnumeric

1416−instance PGAvg 'PGint8 'PGnumeric

1417−instance PGAvg 'PGnumeric 'PGnumeric

1418−instance PGAvg 'PGfloat4 'PGfloat8

1419−instance PGAvg 'PGfloat8 'PGfloat8

1420−instance PGAvg 'PGinterval 'PGinterval

1421−

1422−-- | >>> :{

1423−-- let

1424−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1425−-- expression = bitAnd #col

1426−-- in printSQL expression

1427−-- :}

1428−-- bit_and("col")

1429−bitAnd

1430− :: int `In` PGIntegral

1431− => Expression schema from 'Ungrouped params (nullity int)

1432− -- ^ what to aggregate

1433− -> Expression schema from ('Grouped bys) params (nullity int)

1434−bitAnd = unsafeAggregate "bit_and"

1435−

1436−-- | >>> :{

1437−-- let

1438−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1439−-- expression = bitOr #col

1440−-- in printSQL expression

1441−-- :}

1442−-- bit_or("col")

1443−bitOr

1444− :: int `In` PGIntegral

1445− => Expression schema from 'Ungrouped params (nullity int)

1446− -- ^ what to aggregate

1447− -> Expression schema from ('Grouped bys) params (nullity int)

1448−bitOr = unsafeAggregate "bit_or"

1449−

1450−-- | >>> :{

1451−-- let

1452−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1453−-- expression = bitAndDistinct #col

1454−-- in printSQL expression

1455−-- :}

1456−-- bit_and(DISTINCT "col")

1457−bitAndDistinct

1458− :: int `In` PGIntegral

1459− => Expression schema from 'Ungrouped params (nullity int)

1460− -- ^ what to aggregate

1461− -> Expression schema from ('Grouped bys) params (nullity int)

1462−bitAndDistinct = unsafeAggregateDistinct "bit_and"

1463−

1464−-- | >>> :{

1465−-- let

1466−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1467−-- expression = bitOrDistinct #col

1468−-- in printSQL expression

1469−-- :}

1470−-- bit_or(DISTINCT "col")

1471−bitOrDistinct

1472− :: int `In` PGIntegral

1473− => Expression schema from 'Ungrouped params (nullity int)

1474− -- ^ what to aggregate

1475− -> Expression schema from ('Grouped bys) params (nullity int)

1476−bitOrDistinct = unsafeAggregateDistinct "bit_or"

1477−

1478−-- | >>> :{

1479−-- let

1480−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1481−-- expression = boolAnd #col

1482−-- in printSQL expression

1483−-- :}

1484−-- bool_and("col")

1485−boolAnd

1486− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1487− -- ^ what to aggregate

1488− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1489−boolAnd = unsafeAggregate "bool_and"

1490−

1491−-- | >>> :{

1492−-- let

1493−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1494−-- expression = boolOr #col

1495−-- in printSQL expression

1496−-- :}

1497−-- bool_or("col")

1498−boolOr

1499− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1500− -- ^ what to aggregate

1501− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1502−boolOr = unsafeAggregate "bool_or"

1503−

1504−-- | >>> :{

1505−-- let

1506−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1507−-- expression = boolAndDistinct #col

1508−-- in printSQL expression

1509−-- :}

1510−-- bool_and(DISTINCT "col")

1511−boolAndDistinct

1512− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1513− -- ^ what to aggregate

1514− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1515−boolAndDistinct = unsafeAggregateDistinct "bool_and"

1516−

1517−-- | >>> :{

1518−-- let

1519−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1520−-- expression = boolOrDistinct #col

1521−-- in printSQL expression

1522−-- :}

1523−-- bool_or(DISTINCT "col")

1524−boolOrDistinct

1525− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1526− -- ^ what to aggregate

1527− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1528−boolOrDistinct = unsafeAggregateDistinct "bool_or"

1529−

1530−-- | A special aggregation that does not require an input

1531−--

1532−-- >>> printSQL countStar

1533−-- count(*)

1534−countStar

1535− :: Expression schema from ('Grouped bys) params ('NotNull 'PGint8)

1536−countStar = UnsafeExpression $ "count(*)"

1537−

1538−-- | >>> :{

1539−-- let

1540−-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

1541−-- expression = count #col

1542−-- in printSQL expression

1543−-- :}

1544−-- count("col")

1545−count

1546− :: Expression schema from 'Ungrouped params ty

1547− -- ^ what to count

1548− -> Expression schema from ('Grouped bys) params ('NotNull 'PGint8)

1549−count = unsafeAggregate "count"

1550−

1551−-- | >>> :{

1552−-- let

1553−-- expression :: Expression schema '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

1554−-- expression = countDistinct #col

1555−-- in printSQL expression

1556−-- :}

1557−-- count(DISTINCT "col")

1558−countDistinct

1559− :: Expression schema from 'Ungrouped params ty

1560− -- ^ what to count

1561− -> Expression schema from ('Grouped bys) params ('NotNull 'PGint8)

1562−countDistinct = unsafeAggregateDistinct "count"

1563−

1564−-- | synonym for `boolAnd`

1565−--

1566−-- >>> :{

1567−-- let

1568−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1569−-- expression = every #col

1570−-- in printSQL expression

1571−-- :}

1572−-- every("col")

1573−every

1574− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1575− -- ^ what to aggregate

1576− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1577−every = unsafeAggregate "every"

1578−

1579−-- | synonym for `boolAndDistinct`

1580−--

1581−-- >>> :{

1582−-- let

1583−-- expression :: Expression schema '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1584−-- expression = everyDistinct #col

1585−-- in printSQL expression

1586−-- :}

1587−-- every(DISTINCT "col")

1588−everyDistinct

1589− :: Expression schema from 'Ungrouped params (nullity 'PGbool)

1590− -- ^ what to aggregate

1591− -> Expression schema from ('Grouped bys) params (nullity 'PGbool)

1592−everyDistinct = unsafeAggregateDistinct "every"

1593−

1594−-- | minimum and maximum aggregation

1595−max_, min_, maxDistinct, minDistinct

1596− :: Expression schema from 'Ungrouped params (nullity ty)

1597− -- ^ what to aggregate

1598− -> Expression schema from ('Grouped bys) params (nullity ty)

1599−max_ = unsafeAggregate "max"

1600−min_ = unsafeAggregate "min"

1601−maxDistinct = unsafeAggregateDistinct "max"

1602−minDistinct = unsafeAggregateDistinct "min"

1603−

1604−{-----------------------------------------

1605−type expressions

1606−-----------------------------------------}

1607−

1608−-- | `TypeExpression`s are used in `cast`s and `createTable` commands.

1609−newtype TypeExpression (schema :: SchemaType) (ty :: NullityType)

1610− = UnsafeTypeExpression { renderTypeExpression :: ByteString }

1611− deriving (GHC.Generic,Show,Eq,Ord,NFData)

1612−

1613−-- | The enum or composite type in a `Typedef` can be expressed by its alias.

1614−typedef

1615− :: Has alias schema ('Typedef ty)

1616− => Alias alias

1617− -> TypeExpression schema (nullity ty)

1618−typedef = UnsafeTypeExpression . renderAlias

1619−

1620−-- | The composite type corresponding to a `Table` definition can be expressed

1621−-- by its alias.

1622−typetable

1623− :: Has alias schema ('Table tab)

1624− => Alias alias

1625− -> TypeExpression schema (nullity ('PGcomposite (TableToRow tab)))

1626−typetable = UnsafeTypeExpression . renderAlias

1627−

1628−-- | The composite type corresponding to a `View` definition can be expressed

1629−-- by its alias.

1630−typeview

1631− :: Has alias schema ('View view)

1632− => Alias alias

1633− -> TypeExpression schema (nullity ('PGcomposite view))

1634−typeview = UnsafeTypeExpression . renderAlias

1635−

1636−-- | logical Boolean (true/false)

1637−bool :: TypeExpression schema (nullity 'PGbool)

1638−bool = UnsafeTypeExpression "bool"

1639−-- | signed two-byte integer

1640−int2, smallint :: TypeExpression schema (nullity 'PGint2)

1641−int2 = UnsafeTypeExpression "int2"

1642−smallint = UnsafeTypeExpression "smallint"

1643−-- | signed four-byte integer

1644−int4, int, integer :: TypeExpression schema (nullity 'PGint4)

1645−int4 = UnsafeTypeExpression "int4"

1646−int = UnsafeTypeExpression "int"

1647−integer = UnsafeTypeExpression "integer"

1648−-- | signed eight-byte integer

1649−int8, bigint :: TypeExpression schema (nullity 'PGint8)

1650−int8 = UnsafeTypeExpression "int8"

1651−bigint = UnsafeTypeExpression "bigint"

1652−-- | arbitrary precision numeric type

1653−numeric :: TypeExpression schema (nullity 'PGnumeric)

1654−numeric = UnsafeTypeExpression "numeric"

1655−-- | single precision floating-point number (4 bytes)

1656−float4, real :: TypeExpression schema (nullity 'PGfloat4)

1657−float4 = UnsafeTypeExpression "float4"

1658−real = UnsafeTypeExpression "real"

1659−-- | double precision floating-point number (8 bytes)

1660−float8, doublePrecision :: TypeExpression schema (nullity 'PGfloat8)

1661−float8 = UnsafeTypeExpression "float8"

1662−doublePrecision = UnsafeTypeExpression "double precision"

1663−-- | variable-length character string

1664−text :: TypeExpression schema (nullity 'PGtext)

1665−text = UnsafeTypeExpression "text"

1666−-- | fixed-length character string

1667−char, character

1668− :: forall n schema nullity. (KnownNat n, 1 <= n)

1669− => TypeExpression schema (nullity ('PGchar n))

1670−char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"

1671−character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"

1672−-- | variable-length character string

1673−varchar, characterVarying

1674− :: forall n schema nullity. (KnownNat n, 1 <= n)

1675− => TypeExpression schema (nullity ('PGvarchar n))

1676−varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"

1677−characterVarying = UnsafeTypeExpression $

1678− "character varying(" <> renderNat @n <> ")"

1679−-- | binary data ("byte array")

1680−bytea :: TypeExpression schema (nullity 'PGbytea)

1681−bytea = UnsafeTypeExpression "bytea"

1682−-- | date and time (no time zone)

1683−timestamp :: TypeExpression schema (nullity 'PGtimestamp)

1684−timestamp = UnsafeTypeExpression "timestamp"

1685−-- | date and time, including time zone

1686−timestampWithTimeZone :: TypeExpression schema (nullity 'PGtimestamptz)

1687−timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

1688−-- | calendar date (year, month, day)

1689−date :: TypeExpression schema (nullity 'PGdate)

1690−date = UnsafeTypeExpression "date"

1691−-- | time of day (no time zone)

1692−time :: TypeExpression schema (nullity 'PGtime)

1693−time = UnsafeTypeExpression "time"

1694−-- | time of day, including time zone

1695−timeWithTimeZone :: TypeExpression schema (nullity 'PGtimetz)

1696−timeWithTimeZone = UnsafeTypeExpression "time with time zone"

1697−-- | time span

1698−interval :: TypeExpression schema (nullity 'PGinterval)

1699−interval = UnsafeTypeExpression "interval"

1700−-- | universally unique identifier

1701−uuid :: TypeExpression schema (nullity 'PGuuid)

1702−uuid = UnsafeTypeExpression "uuid"

1703−-- | IPv4 or IPv6 host address

1704−inet :: TypeExpression schema (nullity 'PGinet)

1705−inet = UnsafeTypeExpression "inet"

1706−-- | textual JSON data

1707−json :: TypeExpression schema (nullity 'PGjson)

1708−json = UnsafeTypeExpression "json"

1709−-- | binary JSON data, decomposed

1710−jsonb :: TypeExpression schema (nullity 'PGjsonb)

1711−jsonb = UnsafeTypeExpression "jsonb"

1712−-- | variable length array

1713−vararray

1714− :: TypeExpression schema pg

1715− -> TypeExpression schema (nullity ('PGvararray pg))

1716−vararray ty = UnsafeTypeExpression $ renderTypeExpression ty <> "[]"

1717−-- | fixed length array

1718−--

1719−-- >>> renderTypeExpression (fixarray @2 json)

1720−-- "json[2]"

1721−fixarray

1722− :: forall n schema nullity pg. KnownNat n

1723− => TypeExpression schema pg

1724− -> TypeExpression schema (nullity ('PGfixarray n pg))

1725−fixarray ty = UnsafeTypeExpression $

1726− renderTypeExpression ty <> "[" <> renderNat @n <> "]"

1727−

1728−-- | `pgtype` is a demoted version of a `PGType`

1729−class PGTyped schema (ty :: NullityType) where

1730− pgtype :: TypeExpression schema ty

1731−instance PGTyped schema (nullity 'PGbool) where pgtype = bool

1732−instance PGTyped schema (nullity 'PGint2) where pgtype = int2

1733−instance PGTyped schema (nullity 'PGint4) where pgtype = int4

1734−instance PGTyped schema (nullity 'PGint8) where pgtype = int8

1735−instance PGTyped schema (nullity 'PGnumeric) where pgtype = numeric

1736−instance PGTyped schema (nullity 'PGfloat4) where pgtype = float4

1737−instance PGTyped schema (nullity 'PGfloat8) where pgtype = float8

1738−instance PGTyped schema (nullity 'PGtext) where pgtype = text

1739−instance (KnownNat n, 1 <= n)

1740− => PGTyped schema (nullity ('PGchar n)) where pgtype = char @n

1741−instance (KnownNat n, 1 <= n)

1742− => PGTyped schema (nullity ('PGvarchar n)) where pgtype = varchar @n

1743−instance PGTyped schema (nullity 'PGbytea) where pgtype = bytea

1744−instance PGTyped schema (nullity 'PGtimestamp) where pgtype = timestamp

1745−instance PGTyped schema (nullity 'PGtimestamptz) where pgtype = timestampWithTimeZone

1746−instance PGTyped schema (nullity 'PGdate) where pgtype = date

1747−instance PGTyped schema (nullity 'PGtime) where pgtype = time

1748−instance PGTyped schema (nullity 'PGtimetz) where pgtype = timeWithTimeZone

1749−instance PGTyped schema (nullity 'PGinterval) where pgtype = interval

1750−instance PGTyped schema (nullity 'PGuuid) where pgtype = uuid

1751−instance PGTyped schema (nullity 'PGjson) where pgtype = json

1752−instance PGTyped schema (nullity 'PGjsonb) where pgtype = jsonb

1753−instance PGTyped schema ty

1754− => PGTyped schema (nullity ('PGvararray ty)) where

1755− pgtype = vararray (pgtype @schema @ty)

1756−instance (KnownNat n, PGTyped schema ty)

1757− => PGTyped schema (nullity ('PGfixarray n ty)) where

1758− pgtype = fixarray @n (pgtype @schema @ty)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hsnew file+447

@@ -0,0 +1,447 @@

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

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+ , PGAvg

30+ ) where

31+

32+import Control.DeepSeq

33+import Data.ByteString (ByteString)

34+import Data.Kind

35+import GHC.TypeLits

36+

37+import qualified GHC.Generics as GHC

38+import qualified Generics.SOP as SOP

39+

40+import Squeal.PostgreSQL.Alias

41+import Squeal.PostgreSQL.Expression

42+import Squeal.PostgreSQL.List

43+import Squeal.PostgreSQL.Render

44+import Squeal.PostgreSQL.Schema

45+

46+-- $setup

47+-- >>> import Squeal.PostgreSQL

48+

49+{- |

50+`Aggregate` functions compute a single result from a set of input values.

51+`Aggregate` functions can be used as `GroupedBy` `Expression`s as well

52+as `Squeal.PostgreSQL.Expression.Window.WindowFunction`s.

53+-}

54+class Aggregate expr1 exprN aggr

55+ | aggr -> expr1, aggr -> exprN where

56+

57+ -- | A special aggregation that does not require an input

58+ --

59+ -- >>> :{

60+ -- let

61+ -- expression :: Expression '[] commons ('Grouped bys) schemas params from ('NotNull 'PGint8)

62+ -- expression = countStar

63+ -- in printSQL expression

64+ -- :}

65+ -- count(*)

66+ countStar :: aggr ('NotNull 'PGint8)

67+

68+ -- | >>> :{

69+ -- let

70+ -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null ty]] ('NotNull 'PGint8)

71+ -- expression = count (All #col)

72+ -- in printSQL expression

73+ -- :}

74+ -- count(ALL "col")

75+ count

76+ :: expr1 ty

77+ -- ^ what to count

78+ -> aggr ('NotNull 'PGint8)

79+

80+ -- | >>> :{

81+ -- let

82+ -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Null 'PGnumeric)

83+ -- expression = sum_ (Distinct #col)

84+ -- in printSQL expression

85+ -- :}

86+ -- sum(DISTINCT "col")

87+ sum_

88+ :: ty `In` PGNum

89+ => expr1 (null ty)

90+ -> aggr ('Null 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 `PGAvg` type of a `PGType`.

438+type family PGAvg ty where

439+ PGAvg 'PGint2 = 'PGnumeric

440+ PGAvg 'PGint4 = 'PGnumeric

441+ PGAvg 'PGint8 = 'PGnumeric

442+ PGAvg 'PGnumeric = 'PGnumeric

443+ PGAvg 'PGfloat4 = 'PGfloat8

444+ PGAvg 'PGfloat8 = 'PGfloat8

445+ PGAvg 'PGinterval = 'PGinterval

446+ PGAvg pg = TypeError

447+ ('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

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.SetOf

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 :: SetOfFunction "unnest" (null ('PGvararray ty)) '["unnest" ::: ty]

127+unnest = unsafeSetOfFunction

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

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 = unsafeUnaryOpR "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 = unsafeUnaryOpR "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 = unsafeUnaryOpR "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 = unsafeUnaryOpR "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 = unsafeUnaryOpR "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 = unsafeUnaryOpR "IS NOT UNKNOWN"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Json.hsnew file+469

@@ -0,0 +1,469 @@

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

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.SetOf

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 => FunctionN 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 => FunctionN 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 :: FunctionN tys (null 'PGjson)

228+ jsonBuildObject = unsafeFunctionN "json_build_object"

229+

230+ jsonbBuildObject :: FunctionN 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 :: FunctionN

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 :: FunctionN

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+ :: FunctionN

314+ '[ null 'PGjsonb

315+ , null ('PGvararray ('NotNull 'PGtext))

316+ , null 'PGjsonb

317+ , null 'PGbool ] (null 'PGjsonb)

318+jsonbSet = unsafeFunctionN "jsonbSet"

319+

320+-- | @ jsonbInsert target path new_value insert_after @

321+--

322+-- Returns target with @new_value@ inserted. If target section designated by

323+-- path is in a JSONB array, @new_value@ will be inserted before target or after

324+-- if @insert_after@ is `Squeal.PostgreSQL.Expression.Logic.true`.

325+-- If target section designated by

326+-- path is in JSONB object, @new_value@ will be inserted only if target does not

327+-- exist. As with the path orientated operators, negative integers that appear

328+-- in path count from the end of JSON arrays.

329+jsonbInsert

330+ :: FunctionN

331+ '[ null 'PGjsonb

332+ , null ('PGvararray ('NotNull 'PGtext))

333+ , null 'PGjsonb

334+ , null 'PGbool ] (null 'PGjsonb)

335+jsonbInsert = unsafeFunctionN "jsonb_insert"

336+

337+-- | Returns its argument as indented JSON text.

338+jsonbPretty :: null 'PGjsonb :--> null 'PGtext

339+jsonbPretty = unsafeFunction "jsonb_pretty"

340+

341+

342+{- | Expands the outermost JSON object into a set of key/value pairs.

343+

344+>>> printSQL (select Star (from (jsonEach (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

345+SELECT * FROM json_each(('{"a":"foo","b":"bar"}' :: json))

346+-}

347+jsonEach :: SetOfFunction "json_each" (null 'PGjson)

348+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

349+jsonEach = unsafeSetOfFunction

350+

351+{- | Expands the outermost binary JSON object into a set of key/value pairs.

352+

353+>>> printSQL (select Star (from (jsonbEach (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

354+SELECT * FROM jsonb_each(('{"a":"foo","b":"bar"}' :: jsonb))

355+-}

356+jsonbEach

357+ :: SetOfFunction "jsonb_each" (nullity 'PGjsonb)

358+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

359+jsonbEach = unsafeSetOfFunction

360+

361+{- | Expands the outermost JSON object into a set of key/value pairs.

362+

363+>>> printSQL (select Star (from (jsonEachText (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

364+SELECT * FROM json_each_text(('{"a":"foo","b":"bar"}' :: json))

365+-}

366+jsonEachText

367+ :: SetOfFunction "json_each_text" (null 'PGjson)

368+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

369+jsonEachText = unsafeSetOfFunction

370+

371+{- | Expands the outermost binary JSON object into a set of key/value pairs.

372+

373+>>> printSQL (select Star (from (jsonbEachText (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

374+SELECT * FROM jsonb_each_text(('{"a":"foo","b":"bar"}' :: jsonb))

375+-}

376+jsonbEachText

377+ :: SetOfFunction "jsonb_each_text" (null 'PGjsonb)

378+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

379+jsonbEachText = unsafeSetOfFunction

380+

381+{- | Returns set of keys in the outermost JSON object.

382+

383+>>> printSQL (jsonObjectKeys (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))

384+json_object_keys(('{"a":"foo","b":"bar"}' :: json))

385+-}

386+jsonObjectKeys

387+ :: SetOfFunction "json_object_keys" (nullity 'PGjson)

388+ '["json_object_keys" ::: 'NotNull 'PGtext]

389+jsonObjectKeys = unsafeSetOfFunction

390+

391+{- | Returns set of keys in the outermost JSON object.

392+

393+>>> printSQL (jsonbObjectKeys (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))

394+jsonb_object_keys(('{"a":"foo","b":"bar"}' :: jsonb))

395+-}

396+jsonbObjectKeys

397+ :: SetOfFunction "jsonb_object_keys" (null 'PGjsonb)

398+ '["jsonb_object_keys" ::: 'NotNull 'PGtext]

399+jsonbObjectKeys = unsafeSetOfFunction

400+

401+-- | Build rows from Json types.

402+type JsonPopulateFunction fun json

403+ = forall schemas row outer commons params

404+ . json `In` PGJsonType

405+ => TypeExpression schemas ('NotNull ('PGcomposite row)) -- ^ row type

406+ -> Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

407+ -- ^ json type

408+ -> FromClause outer commons schemas params '[fun ::: row]

409+

410+unsafePopulateFunction

411+ :: forall fun ty

412+ . KnownSymbol fun => Alias fun -> JsonPopulateFunction fun ty

413+unsafePopulateFunction _fun ty expr = UnsafeFromClause $ renderSymbol @fun

414+ <> parenthesized ("null::" <> renderSQL ty <> ", " <> renderSQL expr)

415+

416+-- | Expands the JSON expression to a row whose columns match the record

417+-- type defined by the given table.

418+jsonPopulateRecord :: JsonPopulateFunction "json_populate_record" 'PGjson

419+jsonPopulateRecord = unsafePopulateFunction #json_populate_record

420+

421+-- | Expands the binary JSON expression to a row whose columns match the record

422+-- type defined by the given table.

423+jsonbPopulateRecord :: JsonPopulateFunction "jsonb_populate_record" 'PGjsonb

424+jsonbPopulateRecord = unsafePopulateFunction #jsonb_populate_record

425+

426+-- | Expands the outermost array of objects in the given JSON expression to a

427+-- set of rows whose columns match the record type defined by the given table.

428+jsonPopulateRecordSet :: JsonPopulateFunction "json_populate_record_set" 'PGjson

429+jsonPopulateRecordSet = unsafePopulateFunction #json_populate_record_set

430+

431+-- | Expands the outermost array of objects in the given binary JSON expression

432+-- to a set of rows whose columns match the record type defined by the given

433+-- table.

434+jsonbPopulateRecordSet :: JsonPopulateFunction "jsonb_populate_record_set" 'PGjsonb

435+jsonbPopulateRecordSet = unsafePopulateFunction #jsonb_populate_record_set

436+

437+-- | Build rows from Json types.

438+type JsonToRecordFunction json

439+ = forall outer commons schemas params tab row

440+ . (SOP.SListI row, json `In` PGJsonType)

441+ => Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

442+ -- ^ json type

443+ -> Aliased (NP (Aliased (TypeExpression schemas))) (tab ::: row)

444+ -- ^ row type

445+ -> FromClause outer commons schemas params '[tab ::: row]

446+

447+unsafeRecordFunction :: ByteString -> JsonToRecordFunction json

448+unsafeRecordFunction fun expr (types `As` tab) = UnsafeFromClause $

449+ fun <> parenthesized (renderSQL expr) <+> "AS" <+> renderSQL tab

450+ <> parenthesized (renderCommaSeparated renderTy types)

451+ where

452+ renderTy :: Aliased (TypeExpression schemas) ty -> ByteString

453+ renderTy (ty `As` alias) = renderSQL alias <+> renderSQL ty

454+

455+-- | Builds an arbitrary record from a JSON object.

456+jsonToRecord :: JsonToRecordFunction 'PGjson

457+jsonToRecord = unsafeRecordFunction "json_to_record"

458+

459+-- | Builds an arbitrary record from a binary JSON object.

460+jsonbToRecord :: JsonToRecordFunction 'PGjsonb

461+jsonbToRecord = unsafeRecordFunction "jsonb_to_record"

462+

463+-- | Builds an arbitrary set of records from a JSON array of objects.

464+jsonToRecordSet :: JsonToRecordFunction 'PGjson

465+jsonToRecordSet = unsafeRecordFunction "json_to_record_set"

466+

467+-- | Builds an arbitrary set of records from a binary JSON array of objects.

468+jsonbToRecordSet :: JsonToRecordFunction 'PGjsonb

469+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

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

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_ = unsafeUnaryOpL "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+102

@@ -0,0 +1,102 @@

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

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_

41+ :: float `In` PGFloating

42+ => FunctionN '[ null float, null float] (null float)

43+atan2_ = unsafeFunctionN "atan2"

44+

45+

46+-- | integer division, truncates the result

47+--

48+-- >>> :{

49+-- let

50+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

51+-- expression = 5 `quot_` 2

52+-- in printSQL expression

53+-- :}

54+-- (5 / 2)

55+quot_

56+ :: int `In` PGIntegral

57+ => Operator (null int) (null int) (null int)

58+quot_ = unsafeBinaryOp "/"

59+

60+-- | remainder upon integer division

61+--

62+-- >>> :{

63+-- let

64+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

65+-- expression = 5 `rem_` 2

66+-- in printSQL expression

67+-- :}

68+-- (5 % 2)

69+rem_

70+ :: int `In` PGIntegral

71+ => Operator (null int) (null int) (null int)

72+rem_ = unsafeBinaryOp "%"

73+

74+-- | >>> :{

75+-- let

76+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

77+-- expression = trunc pi

78+-- in printSQL expression

79+-- :}

80+-- trunc(pi())

81+trunc :: frac `In` PGFloating => null frac :--> null frac

82+trunc = unsafeFunction "trunc"

83+

84+-- | >>> :{

85+-- let

86+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

87+-- expression = round_ pi

88+-- in printSQL expression

89+-- :}

90+-- round(pi())

91+round_ :: frac `In` PGFloating => null frac :--> null frac

92+round_ = unsafeFunction "round"

93+

94+-- | >>> :{

95+-- let

96+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

97+-- expression = ceiling_ pi

98+-- in printSQL expression

99+-- :}

100+-- ceiling(pi())

101+ceiling_ :: frac `In` PGFloating => null frac :--> null frac

102+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

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 :: FunctionN '[ '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

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/SetOf.hsnew file+106

@@ -0,0 +1,106 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.SetOf

3+Description: Set returning functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

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.SetOf

24+ ( generateSeries

25+ , generateSeriesStep

26+ , generateSeriesTimestamp

27+ , SetOfFunction

28+ , unsafeSetOfFunction

29+ , SetOfFunctionN

30+ , unsafeSetOfFunctionN

31+ ) where

32+

33+import GHC.TypeLits

34+

35+import qualified Generics.SOP as SOP

36+

37+import Squeal.PostgreSQL.Alias

38+import Squeal.PostgreSQL.Expression

39+import Squeal.PostgreSQL.List

40+import Squeal.PostgreSQL.Render

41+import Squeal.PostgreSQL.Query

42+import Squeal.PostgreSQL.Schema

43+

44+{- |

45+A @RankNType@ for set returning functions with 1 argument.

46+-}

47+type SetOfFunction fun ty setof

48+ = forall outer commons schemas params

49+ . Expression outer commons 'Ungrouped schemas params '[] ty

50+ -- ^ input

51+ -> FromClause outer commons schemas params '[fun ::: setof]

52+ -- ^ output

53+

54+-- | Escape hatch for a set returning function with 1 argument.

55+unsafeSetOfFunction

56+ :: forall fun ty setof. KnownSymbol fun

57+ => SetOfFunction fun ty setof -- ^ set returning function

58+unsafeSetOfFunction x = UnsafeFromClause $

59+ renderSymbol @fun <> parenthesized (renderSQL x)

60+

61+{- |

62+A @RankNType@ for set returning functions with multiple argument.

63+-}

64+type SetOfFunctionN fun tys setof

65+ = forall outer commons schemas params

66+ . NP (Expression outer commons 'Ungrouped schemas params '[]) tys

67+ -- ^ inputs

68+ -> FromClause outer commons schemas params '[fun ::: setof]

69+ -- ^ output

70+

71+-- | Escape hatch for a set returning function with multiple argument.

72+unsafeSetOfFunctionN

73+ :: forall fun tys setof. (SOP.SListI tys, KnownSymbol fun)

74+ => SetOfFunctionN fun tys setof -- ^ set returning function

75+unsafeSetOfFunctionN xs = UnsafeFromClause $

76+ renderSymbol @fun <> parenthesized (renderCommaSeparated renderSQL xs)

77+

78+{- | @generateSeries (start *: stop)@

79+

80+Generate a series of values, from @start@ to @stop@ with a step size of one

81+-}

82+generateSeries

83+ :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

84+ => SetOfFunctionN "generate_series" '[ null ty, null ty]

85+ '["generate_series" ::: null ty] -- ^ set returning function

86+generateSeries = unsafeSetOfFunctionN

87+

88+{- | @generateSeries (start :* stop *: step)@

89+

90+Generate a series of values, from @start@ to @stop@ with a step size of @step@

91+-}

92+generateSeriesStep

93+ :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

94+ => SetOfFunctionN "generate_series" '[null ty, null ty, null ty]

95+ '["generate_series" ::: null ty] -- ^ set returning function

96+generateSeriesStep = unsafeSetOfFunctionN

97+

98+{- | @generateSeries (start :* stop *: step)@

99+

100+Generate a series of values, from @start@ to @stop@ with a step size of @step@

101+-}

102+generateSeriesTimestamp

103+ :: ty `In` '[ 'PGtimestamp, 'PGtimestamptz]

104+ => SetOfFunctionN "generate_series" '[null ty, null ty, null 'PGinterval]

105+ '["generate_series" ::: null ty] -- ^ set returning function

106+generateSeriesTimestamp = unsafeSetOfFunctionN

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

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

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

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+158

@@ -0,0 +1,158 @@

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

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+(.!) = unsafeUnaryOpL "!!"

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

109+ :: FunctionN '[null 'PGtsvector, null ('PGchar 1)] (null 'PGtsvector)

110+setWeight = unsafeFunctionN "set_weight"

111+

112+-- | remove positions and weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

113+strip :: null 'PGtsvector :--> null 'PGtsvector

114+strip = unsafeFunction "strip"

115+

116+-- | @jsonToTSvector (document *: filter)@

117+-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

118+-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

119+-- filter is a `Squeal.PostgreSQL.Expression.Type.json` array, that enumerates what kind of elements

120+-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

121+-- Possible values for filter are "string" (to include all string values),

122+-- "numeric" (to include all numeric values in the string format),

123+-- "boolean" (to include all Boolean values in the string format "true"/"false"),

124+-- "key" (to include all keys) or "all" (to include all above).

125+-- These values can be combined together to include, e.g. all string and numeric values.

126+jsonToTSvector :: FunctionN '[null 'PGjson, null 'PGjson] (null 'PGtsvector)

127+jsonToTSvector = unsafeFunctionN "json_to_tsvector"

128+

129+-- | @jsonbToTSvector (document *: filter)@

130+-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

131+-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

132+-- filter is a `Squeal.PostgreSQL.Expression.Type.jsonb` array, that enumerates what kind of elements

133+-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

134+-- Possible values for filter are "string" (to include all string values),

135+-- "numeric" (to include all numeric values in the string format),

136+-- "boolean" (to include all Boolean values in the string format "true"/"false"),

137+-- "key" (to include all keys) or "all" (to include all above).

138+-- These values can be combined together to include, e.g. all string and numeric values.

139+jsonbToTSvector :: FunctionN '[null 'PGjsonb, null 'PGjsonb] (null 'PGtsvector)

140+jsonbToTSvector = unsafeFunctionN "jsonb_to_tsvector"

141+

142+-- | remove given lexeme from `Squeal.PostgreSQL.Expression.Type.tsvector`

143+tsDelete :: FunctionN

144+ '[null 'PGtsvector, null ('PGvararray ('NotNull 'PGtext))]

145+ (null 'PGtsvector)

146+tsDelete = unsafeFunctionN "ts_delete"

147+

148+-- | select only elements with given weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

149+tsFilter :: FunctionN

150+ '[null 'PGtsvector, null ('PGvararray ('NotNull ('PGchar 1)))]

151+ (null 'PGtsvector)

152+tsFilter = unsafeFunctionN "ts_filter"

153+

154+-- | display a `Squeal.PostgreSQL.Expression.Type.tsquery` match

155+tsHeadline

156+ :: document `In` '[ 'PGtext, 'PGjson, 'PGjsonb]

157+ => FunctionN '[null document, null 'PGtsquery] (null 'PGtext)

158+tsHeadline = unsafeFunctionN "ts_headline"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Time.hsnew file+197

@@ -0,0 +1,197 @@

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

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+#-}

21+

22+module Squeal.PostgreSQL.Expression.Time

23+ ( TimeOp (..)

24+ , currentDate

25+ , currentTime

26+ , currentTimestamp

27+ , localTime

28+ , localTimestamp

29+ , now

30+ , makeDate

31+ , makeTime

32+ , makeTimestamp

33+ , makeTimestamptz

34+ , interval_

35+ , TimeUnit (..)

36+ ) where

37+

38+import Data.String

39+

40+import qualified GHC.Generics as GHC

41+import qualified Generics.SOP as SOP

42+

43+import Squeal.PostgreSQL.Expression

44+import Squeal.PostgreSQL.Render

45+import Squeal.PostgreSQL.Schema

46+

47+-- $setup

48+-- >>> import Squeal.PostgreSQL

49+

50+-- | >>> printSQL currentDate

51+-- CURRENT_DATE

52+currentDate :: Expr (null 'PGdate)

53+currentDate = UnsafeExpression "CURRENT_DATE"

54+

55+-- | >>> printSQL currentTime

56+-- CURRENT_TIME

57+currentTime :: Expr (null 'PGtimetz)

58+currentTime = UnsafeExpression "CURRENT_TIME"

59+

60+-- | >>> printSQL currentTimestamp

61+-- CURRENT_TIMESTAMP

62+currentTimestamp :: Expr (null 'PGtimestamptz)

63+currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

64+

65+-- | >>> printSQL localTime

66+-- LOCALTIME

67+localTime :: Expr (null 'PGtime)

68+localTime = UnsafeExpression "LOCALTIME"

69+

70+-- | >>> printSQL localTimestamp

71+-- LOCALTIMESTAMP

72+localTimestamp :: Expr (null 'PGtimestamp)

73+localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

74+

75+-- | Current date and time (equivalent to `currentTimestamp`)

76+--

77+-- >>> printSQL now

78+-- now()

79+now :: Expr (null 'PGtimestamptz)

80+now = UnsafeExpression "now()"

81+

82+{-|

83+Create date from year, month and day fields

84+

85+>>> printSQL (makeDate (1984 :* 7 *: 3))

86+make_date(1984, 7, 3)

87+-}

88+makeDate :: FunctionN

89+ '[ null 'PGint4, null 'PGint4, null 'PGint4 ]

90+ ( null 'PGdate )

91+makeDate = unsafeFunctionN "make_date"

92+

93+{-|

94+Create time from hour, minute and seconds fields

95+

96+>>> printSQL (makeTime (8 :* 15 *: 23.5))

97+make_time(8, 15, 23.5)

98+-}

99+makeTime :: FunctionN

100+ '[ null 'PGint4, null 'PGint4, null 'PGfloat8 ]

101+ ( null 'PGtime )

102+makeTime = unsafeFunctionN "make_time"

103+

104+{-|

105+Create timestamp from year, month, day, hour, minute and seconds fields

106+

107+>>> printSQL (makeTimestamp (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

108+make_timestamp(2013, 7, 15, 8, 15, 23.5)

109+-}

110+makeTimestamp :: FunctionN

111+ '[ null 'PGint4, null 'PGint4, null 'PGint4

112+ , null 'PGint4, null 'PGint4, null 'PGfloat8 ]

113+ ( null 'PGtimestamp )

114+makeTimestamp = unsafeFunctionN "make_timestamp"

115+

116+{-|

117+Create timestamp with time zone from

118+year, month, day, hour, minute and seconds fields;

119+the current time zone is used

120+

121+>>> printSQL (makeTimestamptz (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

122+make_timestamptz(2013, 7, 15, 8, 15, 23.5)

123+-}

124+makeTimestamptz :: FunctionN

125+ '[ null 'PGint4, null 'PGint4, null 'PGint4

126+ , null 'PGint4, null 'PGint4, null 'PGfloat8 ]

127+ ( null 'PGtimestamptz )

128+makeTimestamptz = unsafeFunctionN "make_timestamptz"

129+

130+{-|

131+Affine space operations on time types.

132+-}

133+class TimeOp time diff | time -> diff where

134+ {-|

135+ >>> printSQL (makeDate (1984 :* 7 *: 3) !+ 365)

136+ (make_date(1984, 7, 3) + 365)

137+ -}

138+ (!+) :: Operator (null time) (null diff) (null time)

139+ (!+) = unsafeBinaryOp "+"

140+ {-|

141+ >>> printSQL (365 +! makeDate (1984 :* 7 *: 3))

142+ (365 + make_date(1984, 7, 3))

143+ -}

144+ (+!) :: Operator (null diff) (null time) (null time)

145+ (+!) = unsafeBinaryOp "+"

146+ {-|

147+ >>> printSQL (makeDate (1984 :* 7 *: 3) !- 365)

148+ (make_date(1984, 7, 3) - 365)

149+ -}

150+ (!-) :: Operator (null time) (null diff) (null time)

151+ (!-) = unsafeBinaryOp "-"

152+ {-|

153+ >>> printSQL (makeDate (1984 :* 7 *: 3) !-! currentDate)

154+ (make_date(1984, 7, 3) - CURRENT_DATE)

155+ -}

156+ (!-!) :: Operator (null time) (null time) (null diff)

157+ (!-!) = unsafeBinaryOp "-"

158+instance TimeOp 'PGtimestamp 'PGinterval

159+instance TimeOp 'PGtimestamptz 'PGinterval

160+instance TimeOp 'PGtime 'PGinterval

161+instance TimeOp 'PGtimetz 'PGinterval

162+instance TimeOp 'PGinterval 'PGinterval

163+instance TimeOp 'PGdate 'PGint4

164+infixl 6 !+

165+infixl 6 +!

166+infixl 6 !-

167+infixl 6 !-!

168+

169+-- | A `TimeUnit` to use in `interval_` construction.

170+data TimeUnit

171+ = Years | Months | Weeks | Days

172+ | Hours | Minutes | Seconds

173+ | Microseconds | Milliseconds

174+ | Decades | Centuries | Millennia

175+ deriving (Eq, Ord, Show, Read, Enum, GHC.Generic)

176+instance SOP.Generic TimeUnit

177+instance SOP.HasDatatypeInfo TimeUnit

178+instance RenderSQL TimeUnit where

179+ renderSQL = \case

180+ Years -> "years"

181+ Months -> "months"

182+ Weeks -> "weeks"

183+ Days -> "days"

184+ Hours -> "hours"

185+ Minutes -> "minutes"

186+ Seconds -> "seconds"

187+ Microseconds -> "microseconds"

188+ Milliseconds -> "milliseconds"

189+ Decades -> "decades"

190+ Centuries -> "centuries"

191+ Millennia -> "millennia"

192+

193+-- | >>> printSQL $ interval_ 7 Days

194+-- (INTERVAL '7.0 days')

195+interval_ :: Double -> TimeUnit -> Expr (null 'PGinterval)

196+interval_ num unit = UnsafeExpression . parenthesized $ "INTERVAL" <+>

197+ "'" <> fromString (show num) <+> renderSQL unit <> "'"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Type.hsnew file+295

@@ -0,0 +1,295 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression

3+Description: Type expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

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+#-}

27+

28+module Squeal.PostgreSQL.Expression.Type

29+ ( TypeExpression (..)

30+ , cast

31+ , astype

32+ , PGTyped (..)

33+ , typedef

34+ , typetable

35+ , typeview

36+ , bool

37+ , int2

38+ , smallint

39+ , int4

40+ , int

41+ , integer

42+ , int8

43+ , bigint

44+ , numeric

45+ , float4

46+ , real

47+ , float8

48+ , doublePrecision

49+ , money

50+ , text

51+ , char

52+ , character

53+ , varchar

54+ , characterVarying

55+ , bytea

56+ , timestamp

57+ , timestampWithTimeZone

58+ , date

59+ , time

60+ , timeWithTimeZone

61+ , interval

62+ , uuid

63+ , inet

64+ , json

65+ , jsonb

66+ , vararray

67+ , fixarray

68+ , tsvector

69+ , tsquery

70+ ) where

71+

72+import Control.DeepSeq

73+import Data.ByteString

74+import Data.String

75+import GHC.TypeLits

76+

77+import qualified Data.ByteString as ByteString

78+import qualified GHC.Generics as GHC

79+import qualified Generics.SOP as SOP

80+

81+import Squeal.PostgreSQL.Alias

82+import Squeal.PostgreSQL.Expression

83+import Squeal.PostgreSQL.Render

84+import Squeal.PostgreSQL.Schema

85+

86+-- $setup

87+-- >>> import Squeal.PostgreSQL

88+

89+-- When a `cast` is applied to an `Expression` of a known type, it

90+-- represents a run-time type conversion. The cast will succeed only if a

91+-- suitable type conversion operation has been defined.

92+--

93+-- | >>> printSQL $ true & cast int4

94+-- (TRUE :: int4)

95+cast

96+ :: TypeExpression schemas ty1

97+ -- ^ type to cast as

98+ -> Expression outer commons grp schemas params from ty0

99+ -- ^ value to convert

100+ -> Expression outer commons grp schemas params from ty1

101+cast ty x = UnsafeExpression $ parenthesized $

102+ renderSQL x <+> "::" <+> renderSQL ty

103+

104+-- | A safe version of `cast` which just matches a value with its type.

105+--

106+-- >>> printSQL (1 & astype int)

107+-- (1 :: int)

108+astype

109+ :: TypeExpression schemas ty

110+ -- ^ type to specify as

111+ -> Expression outer commons grp schemas params from ty

112+ -- ^ value

113+ -> Expression outer commons grp schemas params from ty

114+astype = cast

115+

116+{-----------------------------------------

117+type expressions

118+-----------------------------------------}

119+

120+-- | `TypeExpression`s are used in `cast`s and

121+-- `Squeal.PostgreSQL.Definition.createTable` commands.

122+newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)

123+ = UnsafeTypeExpression { renderTypeExpression :: ByteString }

124+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

125+instance RenderSQL (TypeExpression schemas ty) where

126+ renderSQL = renderTypeExpression

127+

128+-- | The enum or composite type in a `Typedef` can be expressed by its alias.

129+typedef

130+ :: (Has sch schemas schema, Has td schema ('Typedef ty))

131+ => QualifiedAlias sch td

132+ -> TypeExpression schemas (null ty)

133+typedef = UnsafeTypeExpression . renderSQL

134+

135+-- | The composite type corresponding to a `Table` definition can be expressed

136+-- by its alias.

137+typetable

138+ :: (Has sch schemas schema, Has tab schema ('Table table))

139+ => QualifiedAlias sch tab

140+ -> TypeExpression schemas (null ('PGcomposite (TableToRow table)))

141+typetable = UnsafeTypeExpression . renderSQL

142+

143+-- | The composite type corresponding to a `View` definition can be expressed

144+-- by its alias.

145+typeview

146+ :: (Has sch schemas schema, Has vw schema ('View view))

147+ => QualifiedAlias sch vw

148+ -> TypeExpression schemas (null ('PGcomposite view))

149+typeview = UnsafeTypeExpression . renderSQL

150+

151+-- | logical Boolean (true/false)

152+bool :: TypeExpression schemas (null 'PGbool)

153+bool = UnsafeTypeExpression "bool"

154+-- | signed two-byte integer

155+int2, smallint :: TypeExpression schemas (null 'PGint2)

156+int2 = UnsafeTypeExpression "int2"

157+smallint = UnsafeTypeExpression "smallint"

158+-- | signed four-byte integer

159+int4, int, integer :: TypeExpression schemas (null 'PGint4)

160+int4 = UnsafeTypeExpression "int4"

161+int = UnsafeTypeExpression "int"

162+integer = UnsafeTypeExpression "integer"

163+-- | signed eight-byte integer

164+int8, bigint :: TypeExpression schemas (null 'PGint8)

165+int8 = UnsafeTypeExpression "int8"

166+bigint = UnsafeTypeExpression "bigint"

167+-- | arbitrary precision numeric type

168+numeric :: TypeExpression schemas (null 'PGnumeric)

169+numeric = UnsafeTypeExpression "numeric"

170+-- | single precision floating-point number (4 bytes)

171+float4, real :: TypeExpression schemas (null 'PGfloat4)

172+float4 = UnsafeTypeExpression "float4"

173+real = UnsafeTypeExpression "real"

174+-- | double precision floating-point number (8 bytes)

175+float8, doublePrecision :: TypeExpression schemas (null 'PGfloat8)

176+float8 = UnsafeTypeExpression "float8"

177+doublePrecision = UnsafeTypeExpression "double precision"

178+-- | currency amount

179+money :: TypeExpression schema (null 'PGmoney)

180+money = UnsafeTypeExpression "money"

181+-- | variable-length character string

182+text :: TypeExpression schemas (null 'PGtext)

183+text = UnsafeTypeExpression "text"

184+-- | fixed-length character string

185+char, character

186+ :: forall n schemas null. (KnownNat n, 1 <= n)

187+ => TypeExpression schemas (null ('PGchar n))

188+char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"

189+character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"

190+-- | variable-length character string

191+varchar, characterVarying

192+ :: forall n schemas null. (KnownNat n, 1 <= n)

193+ => TypeExpression schemas (null ('PGvarchar n))

194+varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"

195+characterVarying = UnsafeTypeExpression $

196+ "character varying(" <> renderNat @n <> ")"

197+-- | binary data ("byte array")

198+bytea :: TypeExpression schemas (null 'PGbytea)

199+bytea = UnsafeTypeExpression "bytea"

200+-- | date and time (no time zone)

201+timestamp :: TypeExpression schemas (null 'PGtimestamp)

202+timestamp = UnsafeTypeExpression "timestamp"

203+-- | date and time, including time zone

204+timestampWithTimeZone :: TypeExpression schemas (null 'PGtimestamptz)

205+timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

206+-- | calendar date (year, month, day)

207+date :: TypeExpression schemas (null 'PGdate)

208+date = UnsafeTypeExpression "date"

209+-- | time of day (no time zone)

210+time :: TypeExpression schemas (null 'PGtime)

211+time = UnsafeTypeExpression "time"

212+-- | time of day, including time zone

213+timeWithTimeZone :: TypeExpression schemas (null 'PGtimetz)

214+timeWithTimeZone = UnsafeTypeExpression "time with time zone"

215+-- | time span

216+interval :: TypeExpression schemas (null 'PGinterval)

217+interval = UnsafeTypeExpression "interval"

218+-- | universally unique identifier

219+uuid :: TypeExpression schemas (null 'PGuuid)

220+uuid = UnsafeTypeExpression "uuid"

221+-- | IPv4 or IPv6 host address

222+inet :: TypeExpression schemas (null 'PGinet)

223+inet = UnsafeTypeExpression "inet"

224+-- | textual JSON data

225+json :: TypeExpression schemas (null 'PGjson)

226+json = UnsafeTypeExpression "json"

227+-- | binary JSON data, decomposed

228+jsonb :: TypeExpression schemas (null 'PGjsonb)

229+jsonb = UnsafeTypeExpression "jsonb"

230+-- | variable length array

231+vararray

232+ :: TypeExpression schemas pg

233+ -> TypeExpression schemas (null ('PGvararray pg))

234+vararray ty = UnsafeTypeExpression $ renderSQL ty <> "[]"

235+-- | fixed length array

236+--

237+-- >>> renderSQL (fixarray @'[2] json)

238+-- "json[2]"

239+fixarray

240+ :: forall dims schemas null pg. SOP.All KnownNat dims

241+ => TypeExpression schemas pg

242+ -> TypeExpression schemas (null ('PGfixarray dims pg))

243+fixarray ty = UnsafeTypeExpression $

244+ renderSQL ty <> renderDims @dims

245+ where

246+ renderDims :: forall ns. SOP.All KnownNat ns => ByteString

247+ renderDims =

248+ ("[" <>)

249+ . (<> "]")

250+ . ByteString.intercalate "]["

251+ . SOP.hcollapse

252+ $ SOP.hcmap (SOP.Proxy @KnownNat)

253+ (K . fromString . show . natVal)

254+ (SOP.hpure SOP.Proxy :: SOP.NP SOP.Proxy ns)

255+-- | text search query

256+tsvector :: TypeExpression schemas (null 'PGtsvector)

257+tsvector = UnsafeTypeExpression "tsvector"

258+-- | text search document

259+tsquery :: TypeExpression schemas (null 'PGtsquery)

260+tsquery = UnsafeTypeExpression "tsquery"

261+

262+-- | `pgtype` is a demoted version of a `PGType`

263+class PGTyped schemas (ty :: NullityType) where

264+ pgtype :: TypeExpression schemas ty

265+instance PGTyped schemas (null 'PGbool) where pgtype = bool

266+instance PGTyped schemas (null 'PGint2) where pgtype = int2

267+instance PGTyped schemas (null 'PGint4) where pgtype = int4

268+instance PGTyped schemas (null 'PGint8) where pgtype = int8

269+instance PGTyped schemas (null 'PGnumeric) where pgtype = numeric

270+instance PGTyped schemas (null 'PGfloat4) where pgtype = float4

271+instance PGTyped schemas (null 'PGfloat8) where pgtype = float8

272+instance PGTyped schemas (null 'PGmoney) where pgtype = money

273+instance PGTyped schemas (null 'PGtext) where pgtype = text

274+instance (KnownNat n, 1 <= n)

275+ => PGTyped schemas (null ('PGchar n)) where pgtype = char @n

276+instance (KnownNat n, 1 <= n)

277+ => PGTyped schemas (null ('PGvarchar n)) where pgtype = varchar @n

278+instance PGTyped schemas (null 'PGbytea) where pgtype = bytea

279+instance PGTyped schemas (null 'PGtimestamp) where pgtype = timestamp

280+instance PGTyped schemas (null 'PGtimestamptz) where pgtype = timestampWithTimeZone

281+instance PGTyped schemas (null 'PGdate) where pgtype = date

282+instance PGTyped schemas (null 'PGtime) where pgtype = time

283+instance PGTyped schemas (null 'PGtimetz) where pgtype = timeWithTimeZone

284+instance PGTyped schemas (null 'PGinterval) where pgtype = interval

285+instance PGTyped schemas (null 'PGuuid) where pgtype = uuid

286+instance PGTyped schemas (null 'PGjson) where pgtype = json

287+instance PGTyped schemas (null 'PGjsonb) where pgtype = jsonb

288+instance PGTyped schemas ty

289+ => PGTyped schemas (null ('PGvararray ty)) where

290+ pgtype = vararray (pgtype @schemas @ty)

291+instance (SOP.All KnownNat dims, PGTyped schemas ty)

292+ => PGTyped schemas (null ('PGfixarray dims ty)) where

293+ pgtype = fixarray @dims (pgtype @schemas @ty)

294+instance PGTyped schemas (null 'PGtsvector) where pgtype = tsvector

295+instance PGTyped schemas (null 'PGtsquery) where pgtype = tsquery

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

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+141

@@ -0,0 +1,141 @@

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

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+ , AlignedList (..)

37+ , single

38+ , extractList

39+ , mapAligned

40+ , Elem

41+ , In

42+ , Length

43+ ) where

44+

45+import Control.Category

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+import Squeal.PostgreSQL.Render

54+

55+-- | `Join` is simply promoted `++` and is used in @JOIN@s in

56+-- `Squeal.PostgreSQL.Query.FromClause`s.

57+type family Join xs ys where

58+ Join '[] ys = ys

59+ Join (x ': xs) ys = x ': Join xs ys

60+

61+-- | `disjoin` is a utility function for splitting an `NP` list into pieces.

62+disjoin

63+ :: forall xs ys expr. SListI xs

64+ => NP expr (Join xs ys)

65+ -> (NP expr xs, NP expr ys)

66+disjoin = case sList @xs of

67+ SNil -> \ys -> (Nil, ys)

68+ SCons -> \(x :* xsys) ->

69+ case disjoin xsys of (xs,ys) -> (x :* xs, ys)

70+

71+-- | The `Additional` class is for appending

72+-- type-level list parameterized constructors such as `NP`,

73+-- `Squeal.PostgreSQL.Query.Selection`, and `Squeal.PostgreSQL.Query.FromClause`.

74+class Additional expr where

75+ also :: expr ys -> expr xs -> expr (Join xs ys)

76+instance Additional (NP expr) where

77+ also ys = \case

78+ Nil -> ys

79+ x :* xs -> x :* (xs & also ys)

80+

81+-- | An `AlignedList` is a type-aligned list or free category.

82+data AlignedList p x0 x1 where

83+ Done :: AlignedList p x x

84+ (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2

85+infixr 7 :>>

86+instance Category (AlignedList p) where

87+ id = Done

88+ (.) list = \case

89+ Done -> list

90+ step :>> steps -> step :>> (steps >>> list)

91+instance (forall t0 t1. RenderSQL (p t0 t1))

92+ => RenderSQL (AlignedList p x0 x1) where

93+ renderSQL = \case

94+ Done -> ""

95+ step :>> Done -> renderSQL step

96+ step :>> steps -> renderSQL step <> ", " <> renderSQL steps

97+

98+-- | `extractList` turns an `AlignedList` into a standard list.

99+extractList :: (forall a0 a1. p a0 a1 -> b) -> AlignedList p x0 x1 -> [b]

100+extractList f = \case

101+ Done -> []

102+ step :>> steps -> (f step):extractList f steps

103+

104+-- | `mapAligned` applies a function to each element of an `AlignedList`.

105+mapAligned

106+ :: (forall z0 z1. p z0 z1 -> q z0 z1)

107+ -> AlignedList p x0 x1

108+ -> AlignedList q x0 x1

109+mapAligned f = \case

110+ Done -> Done

111+ x :>> xs -> f x :>> mapAligned f xs

112+

113+-- | A `single` step.

114+single :: p x0 x1 -> AlignedList p x0 x1

115+single step = step :>> Done

116+

117+-- | A useful operator for ending an `NP` list of length at least 2 without `Nil`.

118+(*:) :: f x -> f y -> NP f '[x,y]

119+x *: y = x :* y :* Nil

120+infixl 9 *:

121+

122+-- | @Elem@ is a promoted `Data.List.elem`.

123+type family Elem x xs where

124+ Elem x '[] = 'False

125+ Elem x (x ': xs) = 'True

126+ Elem x (_ ': xs) = Elem x xs

127+

128+-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

129+type family In x xs :: Constraint where

130+ In x xs = If (Elem x xs) (() :: Constraint)

131+ (TypeError ('ShowType x ':<>: 'Text "is not in " ':<>: 'ShowType xs))

132+

133+{- | Calculate the `Length` of a type level list

134+

135+>>> :kind! Length '[Char,String,Bool,Double]

136+Length '[Char,String,Bool,Double] :: Nat

137+= 4

138+-}

139+type family Length (xs :: [k]) :: Nat where

140+ Length (x : xs) = 1 + Length xs

141+ Length '[] = 0

squeal-postgresql/src/Squeal/PostgreSQL/Manipulation.hs+390−319

@@ -11,81 +11,140 @@ Squeal data manipulation language.

1111{-# LANGUAGE

1212 DeriveGeneric

1313 , FlexibleContexts

14+ , FlexibleInstances

1415 , GADTs

1516 , GeneralizedNewtypeDeriving

1617 , LambdaCase

18+ , MultiParamTypeClasses

1719 , OverloadedStrings

20+ , PatternSynonyms

21+ , QuantifiedConstraints

1822 , RankNTypes

23+ , ScopedTypeVariables

24+ , TypeApplications

25+ , TypeFamilies

1926 , TypeInType

2027 , TypeOperators

28+ , UndecidableInstances

2129#-}

2230

2331module Squeal.PostgreSQL.Manipulation

2432 ( -- * Manipulation

25− Manipulation (UnsafeManipulation, renderManipulation)

33+ Manipulation_

34+ , Manipulation (..)

2635 , queryStatement

27− , ColumnValue (..)

28− , ReturningClause (ReturningStar, Returning)

29− , ConflictClause (OnConflictDoRaise, OnConflictDoNothing, OnConflictDoUpdate)

3036 -- * Insert

31− , insertRows

32− , insertRow

33− , insertRows_

34− , insertRow_

35− , insertQuery

36− , insertQuery_

37− , renderReturningClause

38− , renderConflictClause

37+ , insertInto

38+ , insertInto_

3939 -- * Update

4040 , update

4141 , update_

4242 -- * Delete

4343 , deleteFrom

4444 , deleteFrom_

45+ -- * Clauses

46+ , Optional (..)

47+ , QueryClause (..)

48+ , pattern Values_

49+ , ReturningClause (..)

50+ , pattern Returning_

51+ , ConflictClause (..)

52+ , ConflictTarget (..)

53+ , ConflictAction (..)

54+ , UsingClause (..)

4555 ) where

4656

4757import Control.DeepSeq

4858import Data.ByteString hiding (foldr)

59+import Data.Kind (Type)

4960

5061import qualified Generics.SOP as SOP

5162import qualified GHC.Generics as GHC

5263

64+import Squeal.PostgreSQL.Alias

5365import Squeal.PostgreSQL.Expression

66+import Squeal.PostgreSQL.Expression.Logic

67+import Squeal.PostgreSQL.List

68+import Squeal.PostgreSQL.PG

5469import Squeal.PostgreSQL.Render

5570import Squeal.PostgreSQL.Query

5671import Squeal.PostgreSQL.Schema

5772

73+-- $setup

74+-- >>> import Squeal.PostgreSQL

75+-- >>> import Data.Int

76+-- >>> import Data.Time

77+

5878{- |

5979A `Manipulation` is a statement which may modify data in the database,

60−but does not alter the schema. Examples are inserts, updates and deletes.

80+but does not alter its schemas. Examples are inserts, updates and deletes.

6181A `Query` is also considered a `Manipulation` even though it does not modify data.

6282

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" <+> 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 or a generalized record using tuples of `P` types and normal Haskell

117+records, whose entries will be targeted using overloaded labels.

118+

119+>>> :set -XDeriveAnyClass -XDerivingStrategies

120+>>> :{

121+data Row a b = Row { col1 :: a, col2 :: b }

122+ deriving stock (GHC.Generic)

123+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

124+:}

125+

63126simple insert:

64127

128+>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]

129+>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

65130>>> :{

66131let

67− manipulation :: Manipulation

68− '[ "tab" ::: 'Table ('[] :=>

69− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

70− , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[] '[]

132+ manipulation :: Manipulation_ (Public Schema) () ()

71133 manipulation =

72− insertRow_ #tab (Set 2 `as` #col1 :* Default `as` #col2)

134+ insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))

73135in printSQL manipulation

74136:}

75137INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)

76138

77139parameterized insert:

78140

141+>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]

142+>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

79143>>> :{

80144let

81− manipulation :: Manipulation

82− '[ "tab" ::: 'Table ('[] :=>

83− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

84− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

85− '[ 'NotNull 'PGint4, 'NotNull 'PGint4 ] '[]

145+ manipulation :: Manipulation_ (Public Schema) (Int32, Int32) ()

86146 manipulation =

87− insertRow_ #tab

88− (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2)

147+ insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))

89148in printSQL manipulation

90149:}

91150INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))

@@ -94,71 +153,48 @@ returning insert:

94153

95154>>> :{

96155let

97− manipulation :: Manipulation

98− '[ "tab" ::: 'Table ('[] :=>

99− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

100− , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[]

101− '["fromOnly" ::: 'NotNull 'PGint4]

156+ manipulation :: Manipulation_ (Public Schema) () (Only Int32)

102157 manipulation =

103− insertRow #tab (Set 2 `as` #col1 :* Default `as` #col2)

158+ insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))

104159 OnConflictDoRaise (Returning (#col1 `as` #fromOnly))

105160in printSQL manipulation

106161:}

107−INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT) RETURNING "col1" AS "fromOnly"

162+INSERT INTO "tab" ("col1", "col2") VALUES (2, 3) RETURNING "col1" AS "fromOnly"

108163

109164upsert:

110165

166+>>> type CustomersColumns = '["name" ::: 'NoDef :=> 'NotNull 'PGtext, "email" ::: 'NoDef :=> 'NotNull 'PGtext]

167+>>> type CustomersConstraints = '["uq" ::: 'Unique '["name"]]

168+>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]

111169>>> :{

112170let

113− manipulation :: Manipulation

114− '[ "tab" ::: 'Table ('[] :=>

115− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

116− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

117− '[] '[ "sum" ::: 'NotNull 'PGint4]

171+ manipulation :: Manipulation_ (Public CustomersSchema) () ()

118172 manipulation =

119− insertRows #tab

120− (Set 2 `as` #col1 :* Set 4 `as` #col2)

121− [Set 6 `as` #col1 :* Set 8 `as` #col2]

122− (OnConflictDoUpdate

123− (Set 2 `as` #col1 :* Same `as` #col2)

124− [#col1 .== #col2])

125− (Returning $ (#col1 + #col2) `as` #sum)

173+ insertInto #customers

174+ (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))

175+ (OnConflict (OnConstraint #uq)

176+ (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))

177+ (Returning_ Nil)

126178in printSQL manipulation

127179:}

128−INSERT INTO "tab" ("col1", "col2") VALUES (2, 4), (6, 8) ON CONFLICT DO UPDATE SET "col1" = 2 WHERE ("col1" = "col2") RETURNING ("col1" + "col2") AS "sum"

180+INSERT INTO "customers" ("name", "email") VALUES (E'John Smith', E'john@smith.com') ON CONFLICT ON CONSTRAINT "uq" DO UPDATE SET "email" = ("excluded"."email" || (E'; ' || "customers"."email"))

129181

130182query insert:

131183

132184>>> :{

133185let

134− manipulation :: Manipulation

135− '[ "tab" ::: 'Table ('[] :=>

136− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

137− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4

138− ])

139− , "other_tab" ::: 'Table ('[] :=>

140− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

141− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4

142− ])

143− ] '[] '[]

144− manipulation =

145− insertQuery_ #tab

146− (selectStar (from (table (#other_tab `as` #t))))

186+ manipulation :: Manipulation_ (Public Schema) () ()

187+ manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))

147188in printSQL manipulation

148189:}

149−INSERT INTO "tab" SELECT * FROM "other_tab" AS "t"

190+INSERT INTO "tab" SELECT * FROM "tab" AS "tab"

150191

151192update:

152193

153194>>> :{

154195let

155− manipulation :: Manipulation

156− '[ "tab" ::: 'Table ('[] :=>

157− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

158− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[] '[]

159− manipulation =

160− update_ #tab (Set 2 `as` #col1 :* Same `as` #col2)

161− (#col1 ./= #col2)

196+ manipulation :: Manipulation_ (Public Schema) () ()

197+ manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)

162198in printSQL manipulation

163199:}

164200UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")

@@ -167,179 +203,169 @@ delete:

167203

168204>>> :{

169205let

170− manipulation :: Manipulation

171− '[ "tab" ::: 'Table ('[] :=>

172− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

173− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[]

174− '[ "col1" ::: 'NotNull 'PGint4

175− , "col2" ::: 'NotNull 'PGint4 ]

176− manipulation = deleteFrom #tab (#col1 .== #col2) ReturningStar

206+ manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)

207+ manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)

177208in printSQL manipulation

178209:}

179210DELETE FROM "tab" WHERE ("col1" = "col2") RETURNING *

180211

181−with manipulation:

212+delete and using clause:

213+

214+>>> :{

215+type Schema3 =

216+ '[ "tab" ::: 'Table ('[] :=> Columns)

217+ , "other_tab" ::: 'Table ('[] :=> Columns)

218+ , "third_tab" ::: 'Table ('[] :=> Columns) ]

219+:}

220+

221+>>> :{

222+let

223+ manipulation :: Manipulation_ (Public Schema3) () ()

224+ manipulation =

225+ deleteFrom #tab (Using (table #other_tab & also (table #third_tab)))

226+ ( (#tab ! #col2 .== #other_tab ! #col2)

227+ .&& (#tab ! #col2 .== #third_tab ! #col2) )

228+ (Returning_ Nil)

229+in printSQL manipulation

230+:}

231+DELETE FROM "tab" USING "other_tab" AS "other_tab", "third_tab" AS "third_tab" WHERE (("tab"."col2" = "other_tab"."col2") AND ("tab"."col2" = "third_tab"."col2"))

182232

183−>>> type ProductsTable = '[] :=> '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

233+with manipulation:

184234

235+>>> type ProductsColumns = '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

236+>>> type ProductsSchema = '["products" ::: 'Table ('[] :=> ProductsColumns), "products_deleted" ::: 'Table ('[] :=> ProductsColumns)]

185237>>> :{

186238let

187− manipulation :: Manipulation

188− '[ "products" ::: 'Table ProductsTable

189− , "products_deleted" ::: 'Table ProductsTable

190− ] '[ 'NotNull 'PGdate] '[]

239+ manipulation :: Manipulation_ (Public ProductsSchema) (Only Day) ()

191240 manipulation = with

192− (deleteFrom #products (#date .< param @1) ReturningStar `as` #deleted_rows)

193− (insertQuery_ #products_deleted (selectStar (from (view (#deleted_rows `as` #t)))))

241+ (deleteFrom #products NoUsing (#date .< param @1) (Returning Star) `as` #del)

242+ (insertInto_ #products_deleted (Subquery (select Star (from (common #del)))))

194243in printSQL manipulation

195244:}

196−WITH "deleted_rows" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "deleted_rows" AS "t"

245+WITH "del" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "del" AS "del"

197246-}

198−

199−newtype Manipulation

200− (schema :: SchemaType)

201− (params :: [NullityType])

202− (columns :: RowType)

203− = UnsafeManipulation { renderManipulation :: ByteString }

204− deriving (GHC.Generic,Show,Eq,Ord,NFData)

205−instance RenderSQL (Manipulation schema params columns) where

206− renderSQL = renderManipulation

207−instance With Manipulation where

208− with Done manip = manip

209− with (cte :>> ctes) manip = UnsafeManipulation $

210− "WITH" <+> renderCommonTableExpressions renderManipulation cte ctes

211− <+> renderManipulation manip

247+type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where

248+ Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)

212249

213250-- | Convert a `Query` into a `Manipulation`.

214251queryStatement

215− :: Query schema params columns

216− -> Manipulation schema params columns

217−queryStatement q = UnsafeManipulation $ renderQuery q

252+ :: Query '[] commons schemas params columns

253+ -> Manipulation commons schemas params columns

254+queryStatement q = UnsafeManipulation $ renderSQL q

218255

219256{-----------------------------------------

220257INSERT statements

221258-----------------------------------------}

222259

223−-- | Insert multiple rows.

224−--

225−-- When a table is created, it contains no data. The first thing to do

226−-- before a database can be of much use is to insert data. Data is

227−-- conceptually inserted one row at a time. Of course you can also insert

228−-- more than one row, but there is no way to insert less than one row.

229−-- Even if you know only some column values, a complete row must be created.

230−insertRows

231− :: ( SOP.SListI columns

232− , SOP.SListI results

233− , Has tab schema ('Table table)

234− , row ~ TableToRow table

235− , columns ~ TableToColumns table )

236− => Alias tab -- ^ table to insert into

237− -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert

238− -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert

239− -> ConflictClause schema table params

240− -- ^ what to do in case of constraint conflict

241− -> ReturningClause schema params row results -- ^ results to return

242− -> Manipulation schema params results

243−insertRows tab rw rws conflict returning = UnsafeManipulation $

244− "INSERT" <+> "INTO" <+> renderAlias tab

245− <+> parenthesized (renderCommaSeparated renderAliasPart rw)

246− <+> "VALUES"

247− <+> commaSeparated

248− ( parenthesized

249− . renderCommaSeparated renderColumnValuePart <$> rw:rws )

250− <> renderConflictClause conflict

251− <> renderReturningClause returning

252− where

253− renderAliasPart, renderColumnValuePart

254− :: Aliased (ColumnValue schema '[] params) ty -> ByteString

255− renderAliasPart (_ `As` name) = renderAlias name

256− renderColumnValuePart (value `As` _) = case value of

257− Default -> "DEFAULT"

258− Set expression -> renderExpression expression

259−

260−-- | Insert a single row.

261−insertRow

262− :: ( SOP.SListI columns

263− , SOP.SListI results

264− , Has tab schema ('Table table)

265− , row ~ TableToRow table

266− , columns ~ TableToColumns table )

267− => Alias tab -- ^ table to insert into

268− -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert

269− -> ConflictClause schema table params

270− -- ^ what to do in case of constraint conflict

271− -> ReturningClause schema params row results -- ^ results to return

272− -> Manipulation schema params results

273−insertRow tab rw = insertRows tab rw []

274−

275−-- | Insert multiple rows returning `Nil` and raising an error on conflicts.

276−insertRows_

277− :: ( SOP.SListI columns

278− , Has tab schema ('Table table)

279− , columns ~ TableToColumns table )

280− => Alias tab -- ^ table to insert into

281− -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert

282− -> [NP (Aliased (ColumnValue schema '[] params)) columns] -- ^ more rows to insert

283− -> Manipulation schema params '[]

284−insertRows_ tab rw rws =

285− insertRows tab rw rws OnConflictDoRaise (Returning Nil)

286−

287−-- | Insert a single row returning `Nil` and raising an error on conflicts.

288−insertRow_

289− :: ( SOP.SListI columns

260+{- |

261+When a table is created, it contains no data. The first thing to do

262+before a database can be of much use is to insert data. Data is

263+conceptually inserted one row at a time. Of course you can also insert

264+more than one row, but there is no way to insert less than one row.

265+Even if you know only some column values, a complete row must be created.

266+-}

267+insertInto

268+ :: ( Has sch schemas schema

290269 , Has tab schema ('Table table)

291− , columns ~ TableToColumns table )

292− => Alias tab -- ^ table to insert into

293− -> NP (Aliased (ColumnValue schema '[] params)) columns -- ^ row to insert

294− -> Manipulation schema params '[]

295−insertRow_ tab rw = insertRow tab rw OnConflictDoRaise (Returning Nil)

296−

297−-- | Insert a `Query`.

298−insertQuery

299− :: ( SOP.SListI columns

300− , SOP.SListI results

270+ , columns ~ TableToColumns table

271+ , row0 ~ TableToRow table

272+ , SOP.SListI columns

273+ , SOP.SListI row1 )

274+ => QualifiedAlias sch tab

275+ -> QueryClause commons schemas params columns

276+ -> ConflictClause tab commons schemas params table

277+ -> ReturningClause commons schemas params '[tab ::: row0] row1

278+ -> Manipulation commons schemas params row1

279+insertInto tab qry conflict ret = UnsafeManipulation $

280+ "INSERT" <+> "INTO" <+> renderSQL tab

281+ <+> renderSQL qry

282+ <> renderSQL conflict

283+ <> renderSQL ret

284+

285+-- | Like `insertInto` but with `OnConflictDoRaise` and no `ReturningClause`.

286+insertInto_

287+ :: ( Has sch schemas schema

301288 , Has tab schema ('Table table)

289+ , columns ~ TableToColumns table

302290 , row ~ TableToRow table

303− , columns ~ TableToColumns table )

304− => Alias tab -- ^ table to insert into

305− -> Query schema params (TableToRow table)

306− -> ConflictClause schema table params

307− -- ^ what to do in case of constraint conflict

308− -> ReturningClause schema params row results -- ^ results to return

309− -> Manipulation schema params results

310−insertQuery tab query conflict returning = UnsafeManipulation $

311− "INSERT" <+> "INTO" <+> renderAlias tab

312− <+> renderQuery query

313− <> renderConflictClause conflict

314− <> renderReturningClause returning

315−

316−-- | Insert a `Query` returning `Nil` and raising an error on conflicts.

317−insertQuery_

318− :: ( SOP.SListI columns

319− , Has tab schema ('Table table)

320− , columns ~ TableToColumns table )

321− => Alias tab -- ^ table to insert into

322− -> Query schema params (TableToRow table)

323− -> Manipulation schema params '[]

324−insertQuery_ tab query =

325− insertQuery tab query OnConflictDoRaise (Returning Nil)

326−

327−-- | `ColumnValue`s are values to insert or update in a row.

328−-- `Same` updates with the same value.

329−-- `Default` inserts or updates with the @DEFAULT@ value.

330−-- `Set` sets a value to be an `Expression`, which can refer to

331−-- existing value in the row for an update.

332−data ColumnValue

333− (schema :: SchemaType)

334− (columns :: RowType)

335− (params :: [NullityType])

336− (ty :: ColumnType)

337− where

338− Same :: ColumnValue schema (column ': columns) params ty

339− Default :: ColumnValue schema columns params ('Def :=> ty)

340− Set

341− :: (forall table. Expression schema '[table ::: columns] 'Ungrouped params ty)

342− -> ColumnValue schema columns params (constraint :=> ty)

291+ , SOP.SListI columns )

292+ => QualifiedAlias sch tab

293+ -> QueryClause commons schemas params columns

294+ -> Manipulation commons schemas params '[]

295+insertInto_ tab qry =

296+ insertInto tab qry OnConflictDoRaise (Returning_ Nil)

297+

298+-- | A `QueryClause` describes what to `insertInto` a table.

299+data QueryClause commons schemas params columns where

300+ -- | `Values` describes `NP` lists of `Aliased` `Optional` `Expression`s

301+ -- whose `ColumnsType` must match the tables'.

302+ Values

303+ :: SOP.SListI columns

304+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns

305+ -> [NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns]

306+ -> QueryClause commons schemas params columns

307+ -- | `Select` describes a subquery that permits use of `Optional` `Expression`s.

308+ Select

309+ :: SOP.SListI columns

310+ => NP (Aliased (Optional (Expression '[] commons grp schemas params from))) columns

311+ -> TableExpression '[] commons grp schemas params from

312+ -> QueryClause commons schemas params columns

313+ -- | `Subquery` describes a subquery whose `RowType` must match the tables'.

314+ Subquery

315+ :: ColumnsToRow columns ~ row

316+ => Query '[] commons schemas params row

317+ -> QueryClause commons schemas params columns

318+

319+instance RenderSQL (QueryClause commons schemas params columns) where

320+ renderSQL = \case

321+ Values row0 rows ->

322+ parenthesized (renderCommaSeparated renderSQLPart row0)

323+ <+> "VALUES"

324+ <+> commaSeparated

325+ ( parenthesized

326+ . renderCommaSeparated renderValuePart <$> row0 : rows )

327+ Select row0 tab ->

328+ parenthesized (renderCommaSeparatedMaybe renderSQLPartMaybe row0)

329+ <+> "SELECT"

330+ <+> renderCommaSeparatedMaybe renderValuePartMaybe row0

331+ <+> renderSQL tab

332+ Subquery qry -> renderQuery qry

333+ where

334+ renderSQLPartMaybe, renderValuePartMaybe

335+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

336+ -> Maybe ByteString

337+ renderSQLPartMaybe = \case

338+ Default `As` _ -> Nothing

339+ Set _ `As` name -> Just $ renderSQL name

340+ renderValuePartMaybe = \case

341+ Default `As` _ -> Nothing

342+ Set value `As` _ -> Just $ renderExpression value

343+ renderSQLPart, renderValuePart

344+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

345+ -> ByteString

346+ renderSQLPart (_ `As` name) = renderSQL name

347+ renderValuePart (value `As` _) = renderSQL value

348+

349+-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s

350+-- whose `ColumnsType` must match the tables'.

351+pattern Values_

352+ :: SOP.SListI columns

353+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns

354+ -> QueryClause commons schemas params columns

355+pattern Values_ vals = Values vals []

356+

357+-- | `Optional` is either `Default` or a value, parameterized by an appropriate

358+-- `ColumnConstraint`.

359+data Optional expr ty where

360+ -- | Use the `Default` value for a column.

361+ Default :: Optional expr ('Def :=> ty)

362+ -- | `Set` a value for a column.

363+ Set :: expr ty -> Optional expr (def :=> ty)

364+

365+instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where

366+ renderSQL = \case

367+ Default -> "DEFAULT"

368+ Set expr -> renderSQL expr

343369

344370-- | A `ReturningClause` computes and return value(s) based

345371-- on each row actually inserted, updated or deleted. This is primarily

@@ -347,74 +373,97 @@ data ColumnValue

347373-- serial sequence number. However, any expression using the table's columns

348374-- is allowed. Only rows that were successfully inserted or updated or

349375-- deleted will be returned. For example, if a row was locked

350−-- but not updated because an `OnConflictDoUpdate` condition was not satisfied,

351−-- the row will not be returned. `ReturningStar` will return all columns

376+-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,

377+-- the row will not be returned. `Returning` `Star` will return all columns

352378-- in the row. Use @Returning Nil@ in the common case where no return

353379-- values are desired.

354−data ReturningClause

355− (schema :: SchemaType)

356− (params :: [NullityType])

357− (row0 :: RowType)

358− (row1 :: RowType)

359− where

360− ReturningStar

361− :: ReturningClause schema params row row

362− Returning

363− :: NP (Aliased (Expression schema '[table ::: row0] 'Ungrouped params)) row1

364− -> ReturningClause schema params row0 row1

365−

366−-- | Render a `ReturningClause`.

367−renderReturningClause

368− :: SOP.SListI results

369− => ReturningClause schema params columns results

370− -> ByteString

371−renderReturningClause = \case

372− ReturningStar -> " RETURNING *"

373− Returning Nil -> ""

374− Returning results -> " RETURNING"

375− <+> renderCommaSeparated (renderAliasedAs renderExpression) results

380+newtype ReturningClause commons schemas params from row =

381+ Returning (Selection '[] commons 'Ungrouped schemas params from row)

382+

383+instance RenderSQL (ReturningClause commons schemas params from row) where

384+ renderSQL = \case

385+ Returning (List Nil) -> ""

386+ Returning selection -> " RETURNING" <+> renderSQL selection

387+

388+-- | `Returning` a `List`

389+pattern Returning_

390+ :: SOP.SListI row

391+ => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row

392+ -> ReturningClause commons schemas params from row

393+pattern Returning_ list = Returning (List list)

376394

377395-- | A `ConflictClause` specifies an action to perform upon a constraint

378396-- violation. `OnConflictDoRaise` will raise an error.

379−-- `OnConflictDoNothing` simply avoids inserting a row.

380−-- `OnConflictDoUpdate` updates the existing row that conflicts with the row

397+-- `OnConflict` `DoNothing` simply avoids inserting a row.

398+-- `OnConflict` `DoUpdate` updates the existing row that conflicts with the row

381399-- proposed for insertion.

382−data ConflictClause

383− (schema :: SchemaType)

384− (table :: TableType)

385− (params :: [NullityType]) where

386− OnConflictDoRaise :: ConflictClause schema table params

387− OnConflictDoNothing :: ConflictClause schema table params

388− OnConflictDoUpdate

389− :: (row ~ TableToRow table, columns ~ TableToColumns table)

390− => NP (Aliased (ColumnValue schema row params)) columns

391− -> [Condition schema '[t ::: row] 'Ungrouped params]

392− -> ConflictClause schema table params

400+data ConflictClause tab commons schemas params table where

401+ OnConflictDoRaise :: ConflictClause tab commons schemas params table

402+ OnConflict

403+ :: ConflictTarget constraints

404+ -> ConflictAction tab commons schemas params columns

405+ -> ConflictClause tab commons schemas params (constraints :=> columns)

393406

394407-- | Render a `ConflictClause`.

395−renderConflictClause

396− :: SOP.SListI (TableToColumns table)

397− => ConflictClause schema table params

408+instance SOP.SListI (TableToColumns table)

409+ => RenderSQL (ConflictClause tab commons schemas params table) where

410+ renderSQL = \case

411+ OnConflictDoRaise -> ""

412+ OnConflict target action -> " ON CONFLICT"

413+ <+> renderSQL target <+> renderSQL action

414+

415+{- |

416+`ConflictAction` specifies an alternative `OnConflict` action.

417+It can be either `DoNothing`, or a `DoUpdate` clause specifying

418+the exact details of the `update` action to be performed in case of a conflict.

419+The `Set` and WHERE `Condition`s in `OnConflict` `DoUpdate` have access to the

420+existing row using the table's name (or an alias), and to rows proposed

421+for insertion using the special @#excluded@ table.

422+-}

423+data ConflictAction tab commons schemas params columns where

424+ -- | `OnConflict` `DoNothing` simply avoids inserting a row as its alternative action.

425+ DoNothing :: ConflictAction tab commons schemas params columns

426+ -- | `OnConflict` `DoUpdate` updates the existing row that conflicts

427+ -- with the row proposed for insertion as its alternative action.

428+ DoUpdate

429+ :: ( row ~ ColumnsToRow columns

430+ , SOP.SListI columns

431+ , columns ~ (col0 ': cols)

432+ , SOP.All (HasIn columns) subcolumns

433+ , AllUnique subcolumns )

434+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]))) subcolumns

435+ -> [Condition '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]]

436+ -- ^ WHERE `Condition`s

437+ -> ConflictAction tab commons schemas params columns

438+

439+instance RenderSQL (ConflictAction tab commons schemas params columns) where

440+ renderSQL = \case

441+ DoNothing -> "DO NOTHING"

442+ DoUpdate updates whs'

443+ -> "DO UPDATE SET"

444+ <+> renderCommaSeparated renderUpdate updates

445+ <> case whs' of

446+ [] -> ""

447+ wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

448+

449+renderUpdate

450+ :: (forall x. RenderSQL (expr x))

451+ => Aliased (Optional expr) ty

398452 -> ByteString

399−renderConflictClause = \case

400− OnConflictDoRaise -> ""

401− OnConflictDoNothing -> " ON CONFLICT DO NOTHING"

402− OnConflictDoUpdate updates whs'

403− -> " ON CONFLICT DO UPDATE SET"

404− <+> renderCommaSeparatedMaybe renderUpdate updates

405− <> case whs' of

406− [] -> ""

407− wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

408− where

409− renderUpdate

410− :: Aliased (ColumnValue schema columns params) column

411− -> Maybe ByteString

412− renderUpdate = \case

413− Same `As` _ -> Nothing

414− Default `As` column -> Just $

415− renderAlias column <+> "=" <+> "DEFAULT"

416− Set expression `As` column -> Just $

417− renderAlias column <+> "=" <+> renderExpression expression

453+renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr

454+

455+-- | A `ConflictTarget` specifies the constraint violation that triggers a

456+-- `ConflictAction`.

457+data ConflictTarget constraints where

458+ OnConstraint

459+ :: Has con constraints constraint

460+ => Alias con

461+ -> ConflictTarget constraints

462+

463+-- | Render a `ConflictTarget`

464+instance RenderSQL (ConflictTarget constraints) where

465+ renderSQL (OnConstraint con) =

466+ "ON" <+> "CONSTRAINT" <+> renderSQL con

418467

419468{-----------------------------------------

420469UPDATE statements

@@ -424,76 +473,98 @@ UPDATE statements

424473-- in all rows that satisfy the condition.

425474update

426475 :: ( SOP.SListI columns

427− , SOP.SListI results

476+ , SOP.SListI row1

477+ , db ~ (commons :=> schemas)

478+ , Has sch schemas schema

428479 , Has tab schema ('Table table)

429− , row ~ TableToRow table

430− , columns ~ TableToColumns table )

431− => Alias tab -- ^ table to update

432− -> NP (Aliased (ColumnValue schema row params)) columns

480+ , row0 ~ TableToRow table

481+ , columns ~ TableToColumns table

482+ , SOP.All (HasIn columns) subcolumns

483+ , AllUnique subcolumns )

484+ => QualifiedAlias sch tab -- ^ table to update

485+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns

433486 -- ^ modified values to replace old values

434− -> (forall t. Condition schema '[t ::: row] 'Ungrouped params)

487+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]

435488 -- ^ condition under which to perform update on a row

436− -> ReturningClause schema params row results -- ^ results to return

437− -> Manipulation schema params results

489+ -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

490+ -> Manipulation commons schemas params row1

438491update tab columns wh returning = UnsafeManipulation $

439492 "UPDATE"

440− <+> renderAlias tab

493+ <+> renderSQL tab

441494 <+> "SET"

442− <+> renderCommaSeparatedMaybe renderUpdate columns

443− <+> "WHERE" <+> renderExpression wh

444− <> renderReturningClause returning

445− where

446− renderUpdate

447− :: Aliased (ColumnValue schema columns params) column

448− -> Maybe ByteString

449− renderUpdate = \case

450− Same `As` _ -> Nothing

451− Default `As` column -> Just $

452− renderAlias column <+> "=" <+> "DEFAULT"

453− Set expression `As` column -> Just $

454− renderAlias column <+> "=" <+> renderExpression expression

495+ <+> renderCommaSeparated renderUpdate columns

496+ <+> "WHERE" <+> renderSQL wh

497+ <> renderSQL returning

455498

456499-- | Update a row returning `Nil`.

457500update_

458501 :: ( SOP.SListI columns

502+ , db ~ (commons :=> schemas)

503+ , Has sch schemas schema

459504 , Has tab schema ('Table table)

460505 , row ~ TableToRow table

461− , columns ~ TableToColumns table )

462− => Alias tab -- ^ table to update

463− -> NP (Aliased (ColumnValue schema row params)) columns

506+ , columns ~ TableToColumns table

507+ , SOP.All (HasIn columns) subcolumns

508+ , AllUnique subcolumns )

509+ => QualifiedAlias sch tab -- ^ table to update

510+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns

464511 -- ^ modified values to replace old values

465− -> (forall t. Condition schema '[t ::: row] 'Ungrouped params)

512+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

466513 -- ^ condition under which to perform update on a row

467− -> Manipulation schema params '[]

468−update_ tab columns wh = update tab columns wh (Returning Nil)

514+ -> Manipulation commons schemas params '[]

515+update_ tab columns wh = update tab columns wh (Returning_ Nil)

469516

470517{-----------------------------------------

471518DELETE statements

472519-----------------------------------------}

473520

474−-- | Delete rows of a table.

521+-- | Specify additional tables.

522+data UsingClause commons schemas params from where

523+ -- | No `UsingClause`

524+ NoUsing :: UsingClause commons schemas params '[]

525+ -- | An `also` list of table expressions, allowing columns

526+ -- from other tables to appear in the WHERE condition.

527+ -- This is similar to the list of tables that can be specified

528+ -- in the FROM Clause of a SELECT statement;

529+ -- for example, an alias for the table name can be specified.

530+ -- Do not repeat the target table in the `Using` list,

531+ -- unless you wish to set up a self-join.

532+ Using

533+ :: FromClause '[] commons schemas params from

534+ -> UsingClause commons schemas params from

535+

536+-- | Delete rows from a table.

475537deleteFrom

476− :: ( SOP.SListI results

538+ :: ( SOP.SListI row1

539+ , db ~ (commons :=> schemas)

540+ , Has sch schemas schema

477541 , Has tab schema ('Table table)

478− , row ~ TableToRow table

542+ , row0 ~ TableToRow table

479543 , columns ~ TableToColumns table )

480− => Alias tab -- ^ table to delete from

481− -> Condition schema '[tab ::: row] 'Ungrouped params

544+ => QualifiedAlias sch tab -- ^ table to delete from

545+ -> UsingClause commons schemas params from

546+ -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)

482547 -- ^ condition under which to delete a row

483− -> ReturningClause schema params row results -- ^ results to return

484− -> Manipulation schema params results

485−deleteFrom tab wh returning = UnsafeManipulation $

486− "DELETE FROM" <+> renderAlias tab

487− <+> "WHERE" <+> renderExpression wh

488− <> renderReturningClause returning

548+ -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

549+ -> Manipulation commons schemas params row1

550+deleteFrom tab using wh returning = UnsafeManipulation $

551+ "DELETE FROM"

552+ <+> renderSQL tab

553+ <> case using of

554+ NoUsing -> ""

555+ Using tables -> " USING" <+> renderSQL tables

556+ <+> "WHERE" <+> renderSQL wh

557+ <> renderSQL returning

489558

490559-- | Delete rows returning `Nil`.

491560deleteFrom_

492− :: ( Has tab schema ('Table table)

561+ :: ( db ~ (commons :=> schemas)

562+ , Has sch schemas schema

563+ , Has tab schema ('Table table)

493564 , row ~ TableToRow table

494565 , columns ~ TableToColumns table )

495− => Alias tab -- ^ table to delete from

496− -> (forall t. Condition schema '[t ::: row] 'Ungrouped params)

566+ => QualifiedAlias sch tab -- ^ table to delete from

567+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

497568 -- ^ condition under which to delete a row

498− -> Manipulation schema params '[]

499−deleteFrom_ tab wh = deleteFrom tab wh (Returning Nil)

569+ -> Manipulation commons schemas params '[]

570+deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)

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 +34,291 @@ type EmailsTable =

2934 ]

3035:}

3136

37+Now we can define some `Migration`s to make our tables.

38+

3239>>> :{

3340let

34− makeUsers :: Migration IO '[] '["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 '["users" ::: 'Table UsersTable]

49− '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]

54+ makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]

55+ '["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 an `AlignedList`.

6570

6671>>> let migrations = makeUsers :>> makeEmails :>> Done

6772

68−>>> :{

69−let

70− numMigrations

71− :: Has "schema_migrations" schema ('Table MigrationsTable)

72− => PQ schema schema IO ()

73− numMigrations = do

74− result <- runQuery (selectStar (from (table (#schema_migrations `as` #m))))

75− num <- ntuples result

76− liftBase $ print num

77−:}

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 (..))

162+

163+import qualified Data.Text.IO as Text (putStrLn)

164+import qualified Generics.SOP as SOP

165+import qualified GHC.Generics as GHC

122166

123−import Squeal.PostgreSQL

167+import Squeal.PostgreSQL.Alias

168+import Squeal.PostgreSQL.Binary

169+import Squeal.PostgreSQL.Definition

170+import Squeal.PostgreSQL.Expression.Comparison

171+import Squeal.PostgreSQL.Expression.Parameter

172+import Squeal.PostgreSQL.Expression.Time

173+import Squeal.PostgreSQL.Expression.Type

174+import Squeal.PostgreSQL.List

175+import Squeal.PostgreSQL.Manipulation

176+import Squeal.PostgreSQL.PQ

177+import Squeal.PostgreSQL.Query

178+import Squeal.PostgreSQL.Schema

179+import Squeal.PostgreSQL.Transaction

124180

125−-- | A `Migration` should contain an inverse pair of

126−-- `up` and `down` instructions and a unique `name`.

127−data Migration io schema0 schema1 = Migration

181+-- | A `Migration` is a named "isomorphism" over a given category.

182+-- It should contain an inverse pair of `up` and `down`

183+-- instructions and a unique `name`.

184+data Migration p schemas0 schemas1 = Migration

128185 { name :: Text -- ^ The `name` of a `Migration`.

129186 -- Each `name` in a `Migration` should be unique.

130− , up :: PQ schema0 schema1 io () -- ^ The `up` instruction of a `Migration`.

131− , down :: PQ schema1 schema0 io () -- ^ The `down` instruction of a `Migration`.

187+ , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.

188+ , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.

189+ } deriving (GHC.Generic)

190+

191+{- |

192+A `Migratory` @p@ is a `Category` for which one can execute or rewind

193+an `AlignedList` of `Migration`s over @p@. This includes the category of pure

194+SQL `Definition`s and the category of impure `Terminally` `PQ` `IO` actions.

195+-}

196+class Category p => Migratory p where

197+

198+ {- |

199+ Run an `AlignedList` of `Migration`s.

200+ Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

201+ In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

202+ if not, `up` the `Migration` and insert its `name` in the `MigrationsTable`.

203+ -}

204+ migrateUp

205+ :: AlignedList (Migration p) schemas0 schemas1

206+ -> PQ schemas0 schemas1 IO ()

207+

208+ {- |

209+ Rewind an `AlignedList` of `Migration`s.

210+ Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

211+ In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

212+ if so, `down` the `Migration` and delete its `name` in the `MigrationsTable`.

213+ -}

214+ migrateDown

215+ :: AlignedList (Migration p) schemas0 schemas1

216+ -> PQ schemas1 schemas0 IO ()

217+

218+instance Migratory Definition where

219+ migrateUp = migrateUp . mapAligned pureMigration

220+ migrateDown = migrateDown . mapAligned pureMigration

221+

222+{- | `Terminally` turns an indexed monad transformer and the monad it transforms

223+into a category by restricting the return type to @()@ and permuting the type variables.

224+This is similar to how applying a monad to @()@ yields a monoid.

225+Since a `Terminally` action has a trivial return value, the only reason

226+to run one is for the side effects, in particular database and other IO effects.

227+-}

228+newtype Terminally trans monad x0 x1 = Terminally

229+ { runTerminally :: trans x0 x1 monad () }

230+ deriving GHC.Generic

231+

232+instance

233+ ( IndexedMonadTransPQ trans

234+ , Monad monad

235+ , forall x0 x1. x0 ~ x1 => Monad (trans x0 x1 monad) )

236+ => Category (Terminally trans monad) where

237+ id = Terminally (return ())

238+ Terminally g . Terminally f = Terminally $ pqThen g f

239+

240+-- | `terminally` ignores the output of a computation, returning @()@ and

241+-- wrapping it up into a `Terminally`. You can lift an action in the base monad

242+-- by using @terminally . lift@.

243+terminally

244+ :: Functor (trans x0 x1 monad)

245+ => trans x0 x1 monad ignore

246+ -> Terminally trans monad x0 x1

247+terminally = Terminally . void

248+

249+-- | A `pureMigration` turns a `Migration` involving only pure SQL

250+-- `Definition`s into a `Migration` that may be combined with arbitrary `IO`.

251+pureMigration

252+ :: Migration Definition schemas0 schemas1

253+ -> Migration (Terminally PQ IO) schemas0 schemas1

254+pureMigration migration = Migration

255+ { name = name migration

256+ , up = terminally . define $ up migration

257+ , down = terminally . define $ down migration

132258 }

133259

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) schema0 schema1 -- ^ migrations to run

141− -> PQ

142− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

143− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

144− io ()

145−migrateUp migration =

146− define createMigrations

147− & pqBind okResult

148− & pqThen (transactionallySchema_ (upMigrations migration))

149− where

260+instance Migratory (Terminally PQ IO) where

150261

151− upMigrations

152− :: MonadBaseControl IO io

153− => AlignedList (Migration io) schema0 schema1

154− -> PQ

155− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

156− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

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 schema0 schema1 -> PQ

165− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

166− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

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 schema0 schema1 -> PQ

182− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

183− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

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) schema0 schema1 -- ^ migrations to rewind

197− -> PQ

198− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

199− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

200− io ()

201−migrateDown migrations =

202− define createMigrations

203− & pqBind okResult

204− & pqThen (transactionallySchema_ (downMigrations migrations))

205− where

262+ migrateUp migration = unsafePQ . transactionally_ $ do

263+ define createMigrations

264+ upMigrations migration

265+

266+ where

267+

268+ upMigrations

269+ :: AlignedList (Migration (Terminally PQ IO)) schemas0 schemas1

270+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

271+ upMigrations = \case

272+ Done -> return ()

273+ step :>> steps -> upMigration step >> upMigrations steps

274+

275+ upMigration

276+ :: Migration (Terminally PQ IO) schemas0 schemas1

277+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

278+ upMigration step = do

279+ executed <- queryExecuted step

280+ unless (executed == 1) $ do

281+ unsafePQ . runTerminally $ up step

282+ manipulateParams_ insertMigration (Only (name step))

283+

284+ queryExecuted

285+ :: Migration (Terminally PQ IO) schemas0 schemas1

286+ -> PQ MigrationsSchemas MigrationsSchemas IO Row

287+ queryExecuted step = do

288+ result <- runQueryParams selectMigration (Only (name step))

289+ ntuples result

290+

291+ migrateDown migrations = unsafePQ . transactionally_ $ do

292+ define createMigrations

293+ downMigrations migrations

294+

295+ where

206296

207− downMigrations

208− :: MonadBaseControl IO io

209− => AlignedList (Migration io) schema0 schema1 -> PQ

210− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

211− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

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 schema0 schema1 -> PQ

220− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

221− ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

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 schema0 schema1 -> PQ

237− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

238− ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

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)

297+ downMigrations

298+ :: AlignedList (Migration (Terminally PQ IO)) schemas0 schemas1

299+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

300+ downMigrations = \case

301+ Done -> return ()

302+ step :>> steps -> downMigrations steps >> downMigration step

303+

304+ downMigration

305+ :: Migration (Terminally PQ IO) schemas0 schemas1

306+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

307+ downMigration step = do

308+ executed <- queryExecuted step

309+ unless (executed == 0) $ do

310+ unsafePQ . runTerminally $ down step

311+ manipulateParams_ deleteMigration (Only (name step))

312+

313+ queryExecuted

314+ :: Migration (Terminally PQ IO) schemas0 schemas1

315+ -> PQ MigrationsSchemas MigrationsSchemas IO Row

316+ queryExecuted step = do

317+ result <- runQueryParams selectMigration (Only (name step))

318+ ntuples result

319+

320+unsafePQ :: (Functor m) => PQ db0 db1 m x -> PQ db0' db1' m x

321+unsafePQ (PQ pq) = PQ $ fmap (SOP.K . SOP.unK) . pq . SOP.K . SOP.unK

253322

254323-- | The `TableType` for a Squeal migration.

255324type MigrationsTable =

@@ -258,10 +327,19 @@ type MigrationsTable =

258327 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz

259328 ]

260329

330+data MigrationRow =

331+ MigrationRow { migrationName :: Text

332+ , migrationTime :: UTCTime }

333+ deriving (GHC.Generic, Show)

334+

335+instance SOP.Generic MigrationRow

336+instance SOP.HasDatatypeInfo MigrationRow

337+

338+type MigrationsSchema = '["schema_migrations" ::: 'Table MigrationsTable]

339+type MigrationsSchemas = Public MigrationsSchema

340+

261341-- | Creates a `MigrationsTable` if it does not already exist.

262−createMigrations

263− :: Has "schema_migrations" schema ('Table MigrationsTable)

264− => Definition schema schema

342+createMigrations :: Definition MigrationsSchemas MigrationsSchemas

265343createMigrations =

266344 createTableIfNotExists #schema_migrations

267345 ( (text & notNullable) `as` #name :*

@@ -269,27 +347,100 @@ createMigrations =

269347 `as` #executed_at )

270348 ( unique #name `as` #migrations_unique_name )

271349

272−-- | Inserts a `Migration` into the `MigrationsTable`

273−insertMigration

274− :: Has "schema_migrations" schema ('Table MigrationsTable)

275− => Manipulation schema '[ 'NotNull 'PGtext] '[]

276−insertMigration = insertRow_ #schema_migrations

277− ( Set (param @1) `as` #name :*

278− Default `as` #executed_at )

279−

280−-- | Deletes a `Migration` from the `MigrationsTable`

281−deleteMigration

282− :: Has "schema_migrations" schema ('Table MigrationsTable)

283− => Manipulation schema '[ 'NotNull 'PGtext ] '[]

350+-- | Inserts a `Migration` into the `MigrationsTable`, returning

351+-- the time at which it was inserted.

352+insertMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

353+insertMigration = insertInto_ #schema_migrations

354+ (Values_ (Set (param @1) `as` #name :* Default `as` #executed_at))

355+

356+-- | Deletes a `Migration` from the `MigrationsTable`, returning

357+-- the time at which it was inserted.

358+deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

284359deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)

285360

286361-- | Selects a `Migration` from the `MigrationsTable`, returning

287−-- the time at which it was executed.

362+-- the time at which it was inserted.

288363selectMigration

289− :: Has "schema_migrations" schema ('Table MigrationsTable)

290− => Query schema '[ 'NotNull 'PGtext ]

291− '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]

292−selectMigration = select

293− (#executed_at `as` #executed_at)

294− ( from (table (#schema_migrations `as` #m))

295− & where_ (#name .== param @1))

364+ :: Query_ MigrationsSchemas (Only Text) (Only UTCTime)

365+selectMigration = select_ (#executed_at `as` #fromOnly)

366+ $ from (table (#schema_migrations))

367+ & where_ (#name .== param @1)

368+

369+selectMigrations :: Query_ MigrationsSchemas () MigrationRow

370+selectMigrations = select_

371+ (#name `as` #migrationName :* #executed_at `as` #migrationTime)

372+ (from (table #schema_migrations))

373+

374+data MigrateCommand

375+ = MigrateStatus

376+ | MigrateUp

377+ | MigrateDown deriving (GHC.Generic, Show)

378+

379+{- | `defaultMain` creates a simple executable

380+from a connection string and a list of `Migration`s. -}

381+defaultMain

382+ :: Migratory p

383+ => ByteString

384+ -- ^ connection string

385+ -> AlignedList (Migration p) db0 db1

386+ -- ^ migrations

387+ -> IO ()

388+defaultMain connectTo migrations = do

389+ command <- readCommandFromArgs

390+ maybe (pure ()) performCommand command

391+

392+ where

393+

394+ performCommand :: MigrateCommand -> IO ()

395+ performCommand = \case

396+ MigrateStatus -> withConnection connectTo $

397+ suppressNotices >> migrateStatus

398+ MigrateUp -> withConnection connectTo $

399+ suppressNotices & pqThen (migrateUp migrations) & pqThen migrateStatus

400+ MigrateDown -> withConnection connectTo $

401+ suppressNotices & pqThen (migrateDown migrations) & pqThen migrateStatus

402+

403+ migrateStatus :: PQ schema schema IO ()

404+ migrateStatus = unsafePQ $ do

405+ runNames <- getRunMigrationNames

406+ let names = extractList name migrations

407+ unrunNames = names \\ runNames

408+ liftIO $ displayRunned runNames >> displayUnrunned unrunNames

409+

410+ suppressNotices :: PQ schema schema IO ()

411+ suppressNotices = manipulate_ $

412+ UnsafeManipulation "SET client_min_messages TO WARNING;"

413+

414+ readCommandFromArgs :: IO (Maybe MigrateCommand)

415+ readCommandFromArgs = getArgs >>= \case

416+ ["migrate"] -> pure . Just $ MigrateUp

417+ ["rollback"] -> pure . Just $ MigrateDown

418+ ["status"] -> pure . Just $ MigrateStatus

419+ args -> displayUsage args >> pure Nothing

420+

421+ displayUsage :: [String] -> IO ()

422+ displayUsage args = do

423+ putStrLn $ "Invalid command: \"" <> unwords args <> "\". Use:"

424+ putStrLn "migrate to run all available migrations"

425+ putStrLn "rollback to rollback all available migrations"

426+ putStrLn "status to display migrations run and migrations left to run"

427+

428+ getRunMigrationNames :: (MonadIO m) => PQ db0 db0 m [Text]

429+ getRunMigrationNames =

430+ fmap migrationName <$> (unsafePQ (define createMigrations & pqThen (runQuery selectMigrations)) >>= getRows)

431+

432+ displayListOfNames :: [Text] -> IO ()

433+ displayListOfNames [] = Text.putStrLn " None"

434+ displayListOfNames xs =

435+ let singleName n = Text.putStrLn $ " - " <> n

436+ in traverse_ singleName xs

437+

438+ displayUnrunned :: [Text] -> IO ()

439+ displayUnrunned unrunned =

440+ Text.putStrLn "Migrations left to run:"

441+ >> displayListOfNames unrunned

442+

443+ displayRunned :: [Text] -> IO ()

444+ displayRunned runned =

445+ Text.putStrLn "Migrations already run:"

446+ >> displayListOfNames runned

squeal-postgresql/src/Squeal/PostgreSQL/PG.hsnew file+366

@@ -0,0 +1,366 @@

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

8+`Squeal.PostgreSQL.PG` provides type families for turning Haskell

9+`Type`s into corresponding Postgres types.

10+-}

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DeriveFoldable

14+ , DeriveFunctor

15+ , DeriveGeneric

16+ , DeriveTraversable

17+ , DefaultSignatures

18+ , FlexibleContexts

19+ , FlexibleInstances

20+ , FunctionalDependencies

21+ , GADTs

22+ , LambdaCase

23+ , OverloadedStrings

24+ , MultiParamTypeClasses

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeFamilies

28+ , TypeInType

29+ , TypeOperators

30+ , UndecidableInstances

31+ , UndecidableSuperClasses

32+#-}

33+

34+module Squeal.PostgreSQL.PG

35+ ( -- * PG embeddings

36+ PG

37+ , NullPG

38+ , TuplePG

39+ , RowPG

40+ -- * Storage newtypes

41+ , Money (..)

42+ , Json (..)

43+ , Jsonb (..)

44+ , Composite (..)

45+ , Enumerated (..)

46+ , VarArray (..)

47+ , FixArray (..)

48+ , SOP.P (..)

49+ -- * Type families

50+ , LabelsPG

51+ , DimPG

52+ , FixPG

53+ , TupleOf

54+ , TupleCodeOf

55+ , RowOf

56+ , ConstructorsOf

57+ , ConstructorNameOf

58+ , ConstructorNamesOf

59+ ) where

60+

61+import Data.Aeson (Value)

62+import Data.Kind (Type)

63+import Data.Int (Int16, Int32, Int64)

64+import Data.Scientific (Scientific)

65+import Data.Time (Day, DiffTime, LocalTime, TimeOfDay, TimeZone, UTCTime)

66+import Data.Vector (Vector)

67+import Data.Word (Word16, Word32, Word64)

68+import Data.UUID.Types (UUID)

69+import GHC.TypeLits

70+import Network.IP.Addr (NetAddr, IP)

71+

72+import qualified Data.ByteString.Lazy as Lazy (ByteString)

73+import qualified Data.ByteString as Strict (ByteString)

74+import qualified Data.Text.Lazy as Lazy (Text)

75+import qualified Data.Text as Strict (Text)

76+import qualified GHC.Generics as GHC

77+import qualified Generics.SOP as SOP

78+import qualified Generics.SOP.Record as SOP

79+import qualified Generics.SOP.Type.Metadata as Type

80+

81+import Squeal.PostgreSQL.Alias

82+import Squeal.PostgreSQL.Schema

83+

84+-- $setup

85+-- >>> import Squeal.PostgreSQL

86+-- >>> import Data.Text (Text)

87+

88+{- | The `PG` type family embeds a subset of Haskell types

89+as Postgres types. As an open type family, `PG` is extensible.

90+

91+>>> :kind! PG LocalTime

92+PG LocalTime :: PGType

93+= 'PGtimestamp

94+

95+>>> newtype MyDouble = My Double

96+>>> :set -XTypeFamilies

97+>>> type instance PG MyDouble = 'PGfloat8

98+-}

99+type family PG (hask :: Type) :: PGType

100+-- | `PGbool`

101+type instance PG Bool = 'PGbool

102+-- | `PGint2`

103+type instance PG Int16 = 'PGint2

104+-- | `PGint4`

105+type instance PG Int32 = 'PGint4

106+-- | `PGint8`

107+type instance PG Int64 = 'PGint8

108+-- | `PGint2`

109+type instance PG Word16 = 'PGint2

110+-- | `PGint4`

111+type instance PG Word32 = 'PGint4

112+-- | `PGint8`

113+type instance PG Word64 = 'PGint8

114+-- | `PGnumeric`

115+type instance PG Scientific = 'PGnumeric

116+-- | `PGfloat4`

117+type instance PG Float = 'PGfloat4

118+-- | `PGfloat8`

119+type instance PG Double = 'PGfloat8

120+-- | `PGchar` @1@

121+type instance PG Char = 'PGchar 1

122+-- | `PGtext`

123+type instance PG Strict.Text = 'PGtext

124+-- | `PGtext`

125+type instance PG Lazy.Text = 'PGtext

126+-- | `PGtext`

127+type instance PG String = 'PGtext

128+-- | `PGbytea`

129+type instance PG Strict.ByteString = 'PGbytea

130+-- | `PGbytea`

131+type instance PG Lazy.ByteString = 'PGbytea

132+-- | `PGtimestamp`

133+type instance PG LocalTime = 'PGtimestamp

134+-- | `PGtimestamptz`

135+type instance PG UTCTime = 'PGtimestamptz

136+-- | `PGdate`

137+type instance PG Day = 'PGdate

138+-- | `PGtime`

139+type instance PG TimeOfDay = 'PGtime

140+-- | `PGtimetz`

141+type instance PG (TimeOfDay, TimeZone) = 'PGtimetz

142+-- | `PGinterval`

143+type instance PG DiffTime = 'PGinterval

144+-- | `PGuuid`

145+type instance PG UUID = 'PGuuid

146+-- | `PGinet`

147+type instance PG (NetAddr IP) = 'PGinet

148+-- | `PGjson`

149+type instance PG Value = 'PGjson

150+

151+{-| The `LabelsPG` type family calculates the constructors of a

152+Haskell enum type.

153+

154+>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

155+>>> instance SOP.Generic Schwarma

156+>>> instance SOP.HasDatatypeInfo Schwarma

157+>>> :kind! LabelsPG Schwarma

158+LabelsPG Schwarma :: [Type.ConstructorName]

159+= '["Beef", "Lamb", "Chicken"]

160+-}

161+type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where

162+ LabelsPG hask =

163+ ConstructorNamesOf (ConstructorsOf (SOP.DatatypeInfoOf hask))

164+

165+{- |

166+`RowPG` turns a Haskell `Type` into a `RowType`.

167+

168+`RowPG` may be applied to normal Haskell record types provided they

169+have `SOP.Generic` and `SOP.HasDatatypeInfo` instances;

170+

171+>>> data Person = Person { name :: Strict.Text, age :: Int32 } deriving GHC.Generic

172+>>> instance SOP.Generic Person

173+>>> instance SOP.HasDatatypeInfo Person

174+>>> :kind! RowPG Person

175+RowPG Person :: [(Symbol, NullityType)]

176+= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

177+-}

178+type family RowPG (hask :: Type) :: RowType where

179+ RowPG hask = RowOf (SOP.RecordCodeOf hask)

180+

181+-- | `RowOf` applies `NullPG` to the fields of a list.

182+type family RowOf (record :: [(Symbol, Type)]) :: RowType where

183+ RowOf '[] = '[]

184+ RowOf (col ::: ty ': record) = col ::: NullPG ty ': RowOf record

185+

186+{- | `NullPG` turns a Haskell type into a `NullityType`.

187+

188+>>> :kind! NullPG Double

189+NullPG Double :: NullityType

190+= 'NotNull 'PGfloat8

191+>>> :kind! NullPG (Maybe Double)

192+NullPG (Maybe Double) :: NullityType

193+= 'Null 'PGfloat8

194+-}

195+type family NullPG (hask :: Type) :: NullityType where

196+ NullPG (Maybe hask) = 'Null (PG hask)

197+ NullPG hask = 'NotNull (PG hask)

198+

199+{- | `TuplePG` turns a Haskell tuple type (including record types) into

200+the corresponding list of `NullityType`s.

201+

202+>>> :kind! TuplePG (Double, Maybe Char)

203+TuplePG (Double, Maybe Char) :: [NullityType]

204+= '[ 'NotNull 'PGfloat8, 'Null ('PGchar 1)]

205+-}

206+type family TuplePG (hask :: Type) :: [NullityType] where

207+ TuplePG hask = TupleOf (TupleCodeOf hask (SOP.Code hask))

208+

209+-- | `TupleOf` turns a list of Haskell `Type`s into a list of `NullityType`s.

210+type family TupleOf (tuple :: [Type]) :: [NullityType] where

211+ TupleOf '[] = '[]

212+ TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple

213+

214+-- | `TupleCodeOf` takes the `SOP.Code` of a haskell `Type`

215+-- and if it's a simple product returns it, otherwise giving a `TypeError`.

216+type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where

217+ TupleCodeOf hask '[tuple] = tuple

218+ TupleCodeOf hask '[] =

219+ TypeError

220+ ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

221+ ':$$: 'Text "It is a void type with no constructors."

222+ )

223+ TupleCodeOf hask (_ ': _ ': _) =

224+ TypeError

225+ ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

226+ ':$$: 'Text "It is a sum type with more than one constructor."

227+ )

228+

229+-- | Calculates constructors of a datatype.

230+type family ConstructorsOf (datatype :: Type.DatatypeInfo)

231+ :: [Type.ConstructorInfo] where

232+ ConstructorsOf ('Type.ADT _module _datatype constructors) =

233+ constructors

234+ ConstructorsOf ('Type.Newtype _module _datatype constructor) =

235+ '[constructor]

236+

237+-- | Calculates the name of a nullary constructor, otherwise

238+-- generates a type error.

239+type family ConstructorNameOf (constructor :: Type.ConstructorInfo)

240+ :: Type.ConstructorName where

241+ ConstructorNameOf ('Type.Constructor name) = name

242+ ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError

243+ ('Text "ConstructorNameOf error: non-nullary constructor "

244+ ':<>: 'Text name)

245+ ConstructorNameOf ('Type.Record name _fields) = TypeError

246+ ('Text "ConstructorNameOf error: non-nullary constructor "

247+ ':<>: 'Text name)

248+

249+-- | Calculate the names of nullary constructors.

250+type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])

251+ :: [Type.ConstructorName] where

252+ ConstructorNamesOf '[] = '[]

253+ ConstructorNamesOf (constructor ': constructors) =

254+ ConstructorNameOf constructor ': ConstructorNamesOf constructors

255+

256+-- | `DimPG` turns Haskell nested homogeneous tuples into a list of lengths.

257+type family DimPG (hask :: Type) :: [Nat] where

258+ DimPG (x,x) = 2 ': DimPG x

259+ DimPG (x,x,x) = 3 ': DimPG x

260+ DimPG (x,x,x,x) = 4 ': DimPG x

261+ DimPG (x,x,x,x,x) = 5 ': DimPG x

262+ DimPG (x,x,x,x,x,x) = 6 ': DimPG x

263+ DimPG (x,x,x,x,x,x,x) = 7 ': DimPG x

264+ DimPG (x,x,x,x,x,x,x,x) = 8 ': DimPG x

265+ DimPG (x,x,x,x,x,x,x,x,x) = 9 ': DimPG x

266+ DimPG (x,x,x,x,x,x,x,x,x,x) = 10 ': DimPG x

267+ DimPG x = '[]

268+

269+-- | `FixPG` extracts `NullPG` of the base type of nested homogeneous tuples.

270+type family FixPG (hask :: Type) :: NullityType where

271+ FixPG (x,x) = FixPG x

272+ FixPG (x,x,x) = FixPG x

273+ FixPG (x,x,x,x) = FixPG x

274+ FixPG (x,x,x,x,x) = FixPG x

275+ FixPG (x,x,x,x,x,x) = FixPG x

276+ FixPG (x,x,x,x,x,x,x) = FixPG x

277+ FixPG (x,x,x,x,x,x,x,x) = FixPG x

278+ FixPG (x,x,x,x,x,x,x,x,x) = FixPG x

279+ FixPG (x,x,x,x,x,x,x,x,x,x) = FixPG x

280+ FixPG (x,x,x,x,x,x,x,x,x,x,x) = FixPG x

281+ FixPG x = NullPG x

282+

283+{- | The `Money` newtype stores a monetary value in terms

284+of the number of cents, i.e. @$2,000.20@ would be expressed as

285+@Money { cents = 200020 }@.

286+

287+>>> import Control.Monad (void)

288+>>> import Control.Monad.IO.Class (liftIO)

289+>>> import Squeal.PostgreSQL

290+>>> :{

291+let

292+ roundTrip :: Query_ (Public '[]) (Only Money) (Only Money)

293+ roundTrip = values_ $ parameter @1 money `as` #fromOnly

294+:}

295+

296+>>> let input = Only (Money 20020)

297+

298+>>> :{

299+withConnection "host=localhost port=5432 dbname=exampledb" $ do

300+ result <- runQueryParams roundTrip input

301+ Just output <- firstRow result

302+ liftIO . print $ input == output

303+:}

304+True

305+-}

306+newtype Money = Money { cents :: Int64 }

307+ deriving (Eq, Ord, Show, Read, GHC.Generic)

308+-- | `PGmoney`

309+type instance PG Money = 'PGmoney

310+

311+{- | The `Json` newtype is an indication that the Haskell

312+type it's applied to should be stored as a `PGjson`.

313+-}

314+newtype Json hask = Json {getJson :: hask}

315+ deriving (Eq, Ord, Show, Read, GHC.Generic)

316+-- | `PGjson`

317+type instance PG (Json hask) = 'PGjson

318+

319+{- | The `Jsonb` newtype is an indication that the Haskell

320+type it's applied to should be stored as a `PGjsonb`.

321+-}

322+newtype Jsonb hask = Jsonb {getJsonb :: hask}

323+ deriving (Eq, Ord, Show, Read, GHC.Generic)

324+-- | `PGjsonb`

325+type instance PG (Jsonb hask) = 'PGjsonb

326+

327+{- | The `Composite` newtype is an indication that the Haskell

328+type it's applied to should be stored as a `PGcomposite`.

329+-}

330+newtype Composite record = Composite {getComposite :: record}

331+ deriving (Eq, Ord, Show, Read, GHC.Generic)

332+-- | `PGcomposite` @(@`RowPG` @hask)@

333+type instance PG (Composite hask) = 'PGcomposite (RowPG hask)

334+

335+{- | The `Enumerated` newtype is an indication that the Haskell

336+type it's applied to should be stored as a `PGenum`.

337+-}

338+newtype Enumerated enum = Enumerated {getEnumerated :: enum}

339+ deriving (Eq, Ord, Show, Read, GHC.Generic)

340+-- | `PGenum` @(@`LabelsPG` @hask)@

341+type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)

342+

343+{- | The `VarArray` newtype is an indication that the Haskell

344+type it's applied to should be stored as a `PGvararray`.

345+

346+>>> :kind! PG (VarArray (Vector Double))

347+PG (VarArray (Vector Double)) :: PGType

348+= 'PGvararray ('NotNull 'PGfloat8)

349+-}

350+newtype VarArray arr = VarArray {getVarArray :: arr}

351+ deriving (Eq, Ord, Show, Read, GHC.Generic)

352+-- | `PGvararray` @(@`NullPG` @hask)@

353+type instance PG (VarArray (Vector hask)) = 'PGvararray (NullPG hask)

354+type instance PG (VarArray [hask]) = 'PGvararray (NullPG hask)

355+

356+{- | The `FixArray` newtype is an indication that the Haskell

357+type it's applied to should be stored as a `PGfixarray`.

358+

359+>>> :kind! PG (FixArray ((Double, Double), (Double, Double)))

360+PG (FixArray ((Double, Double), (Double, Double))) :: PGType

361+= 'PGfixarray '[2, 2] ('NotNull 'PGfloat8)

362+-}

363+newtype FixArray arr = FixArray {getFixArray :: arr}

364+ deriving (Eq, Ord, Show, Read, GHC.Generic)

365+-- | `PGfixarray` @(@`DimPG` @hask) (@`FixPG` @hask)@

366+type instance PG (FixArray hask) = 'PGfixarray (DimPG hask) (FixPG hask)

squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+192−172

@@ -6,12 +6,12 @@ Maintainer: eitan@morphism.tech

66Stability: experimental

88This module is where Squeal commands actually get executed by

9−`LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing

9+`Database.PostgreSQL.LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing

1010a `Definition` and `MonadPQ` for executing a `Manipulation` or `Query`,

1111and a `PQ` type with instances for them.

1212

1313Using Squeal in your application will come down to defining

14−the @schema@ of your database and including @PQ schema schema@ in your

14+the @schemas@ of your database and including @PQ schemas schemas@ in your

1515application's monad transformer stack, giving it an instance of `MonadPQ`.

1616

1717This module also provides functions for retrieving rows from the `LibPQ.Result`

@@ -24,6 +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

@@ -65,15 +64,17 @@ 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 ((&))

@@ -83,6 +84,7 @@ import Data.Traversable

8384import Generics.SOP

8485import PostgreSQL.Binary.Encoding (encodingBytes)

8586

87+import qualified Control.Monad.Fail as Fail

8688import qualified Database.PostgreSQL.LibPQ as LibPQ

8789

8890import Squeal.PostgreSQL.Binary

@@ -104,6 +106,9 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict

104106import qualified Control.Monad.Trans.RWS.Lazy as Lazy

105107import qualified Control.Monad.Trans.RWS.Strict as Strict

106108

109+-- $setup

110+-- >>> import Squeal.PostgreSQL

111+

107112{- | Makes a new connection to the database server.

108113

109114This function opens a new database connection using the parameters taken

@@ -130,22 +135,22 @@ Note that, for now, squeal doesn't offer any protection from connecting

130135with the wrong schema!

131136-}

132137connectdb

133− :: forall schema io

134− . MonadBase IO io

138+ :: forall schemas io

139+ . MonadIO io

135140 => ByteString -- ^ conninfo

136− -> io (K LibPQ.Connection schema)

137−connectdb = fmap K . liftBase . LibPQ.connectdb

141+ -> io (K LibPQ.Connection schemas)

142+connectdb = fmap K . liftIO . LibPQ.connectdb

138143

139144-- | Closes the connection to the server.

140−finish :: MonadBase IO io => K LibPQ.Connection schema -> io ()

141−finish = liftBase . LibPQ.finish . unK

145+finish :: MonadIO io => K LibPQ.Connection schemas -> io ()

146+finish = liftIO . LibPQ.finish . unK

142147

143148-- | Do `connectdb` and `finish` before and after a computation.

144149withConnection

145− :: forall schema0 schema1 io x

146− . MonadBaseControl IO io

150+ :: forall schemas0 schemas1 io x

151+ . MonadUnliftIO io

147152 => ByteString

148− -> PQ schema0 schema1 io x

153+ -> PQ schemas0 schemas1 io x

149154 -> io x

150155withConnection connString action = do

151156 K x <- bracket (connectdb connString) finish (unPQ action)

@@ -153,47 +158,47 @@ withConnection connString action = do

153158

154159-- | Safely `lowerConnection` to a smaller schema.

155160lowerConnection

156− :: K LibPQ.Connection (table ': schema)

157− -> K LibPQ.Connection schema

161+ :: K LibPQ.Connection (schema ': schemas)

162+ -> K LibPQ.Connection schemas

158163lowerConnection (K conn) = K conn

159164

160165-- | We keep track of the schema via an Atkey indexed state monad transformer,

161166-- `PQ`.

162167newtype PQ

163− (schema0 :: SchemaType)

164− (schema1 :: SchemaType)

168+ (schemas0 :: SchemasType)

169+ (schemas1 :: SchemasType)

165170 (m :: Type -> Type)

166171 (x :: Type) =

167− PQ { unPQ :: K LibPQ.Connection schema0 -> m (K x schema1) }

172+ PQ { unPQ :: K LibPQ.Connection schemas0 -> m (K x schemas1) }

168173

169−instance Monad m => Functor (PQ schema0 schema1 m) where

174+instance Monad m => Functor (PQ schemas0 schemas1 m) where

170175 fmap f (PQ pq) = PQ $ \ conn -> do

171176 K x <- pq conn

172177 return $ K (f x)

173178

174−-- | Run a `PQ` and keep the result and the `Connection`.

179+-- | Run a `PQ` and keep the result and the `LibPQ.Connection`.

175180runPQ

176181 :: Functor m

177− => PQ schema0 schema1 m x

178− -> K LibPQ.Connection schema0

179− -> m (x, K LibPQ.Connection schema1)

182+ => PQ schemas0 schemas1 m x

183+ -> K LibPQ.Connection schemas0

184+ -> m (x, K LibPQ.Connection schemas1)

180185runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn

181186 -- K x <- pq conn

182187 -- return (x, K (unK conn))

183188

184−-- | Execute a `PQ` and discard the result but keep the `Connection`.

189+-- | Execute a `PQ` and discard the result but keep the `LibPQ.Connection`.

185190execPQ

186191 :: Functor m

187− => PQ schema0 schema1 m x

188− -> K LibPQ.Connection schema0

189− -> m (K LibPQ.Connection schema1)

192+ => PQ schemas0 schemas1 m x

193+ -> K LibPQ.Connection schemas0

194+ -> m (K LibPQ.Connection schemas1)

190195execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn

191196

192−-- | Evaluate a `PQ` and discard the `Connection` but keep the result.

197+-- | Evaluate a `PQ` and discard the `LibPQ.Connection` but keep the result.

193198evalPQ

194199 :: Functor m

195− => PQ schema0 schema1 m x

196− -> K LibPQ.Connection schema0

200+ => PQ schemas0 schemas1 m x

201+ -> K LibPQ.Connection schemas0

197202 -> m x

198203evalPQ (PQ pq) conn = unK <$> pq conn

199204

@@ -201,60 +206,56 @@ evalPQ (PQ pq) conn = unK <$> pq conn

201206-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).

202207-- An indexed monad transformer transforms a `Monad` into an indexed monad.

203208-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that

204−-- support running `Definition`s using `define` and embedding a computation

205−-- in a larger schema using `pqEmbed`.

209+-- support running `Definition`s using `define`.

206210class IndexedMonadTransPQ pq where

207211

208212 -- | indexed analog of `<*>`

209213 pqAp

210214 :: Monad m

211− => pq schema0 schema1 m (x -> y)

212− -> pq schema1 schema2 m x

213− -> pq schema0 schema2 m y

215+ => pq schemas0 schemas1 m (x -> y)

216+ -> pq schemas1 schemas2 m x

217+ -> pq schemas0 schemas2 m y

214218

215219 -- | indexed analog of `join`

216220 pqJoin

217221 :: Monad m

218− => pq schema0 schema1 m (pq schema1 schema2 m y)

219− -> pq schema0 schema2 m y

222+ => pq schemas0 schemas1 m (pq schemas1 schemas2 m y)

223+ -> pq schemas0 schemas2 m y

220224 pqJoin pq = pq & pqBind id

221225

222226 -- | indexed analog of `=<<`

223227 pqBind

224228 :: Monad m

225− => (x -> pq schema1 schema2 m y)

226− -> pq schema0 schema1 m x

227− -> pq schema0 schema2 m y

229+ => (x -> pq schemas1 schemas2 m y)

230+ -> pq schemas0 schemas1 m x

231+ -> pq schemas0 schemas2 m y

228232

229233 -- | indexed analog of flipped `>>`

230234 pqThen

231235 :: Monad m

232− => pq schema1 schema2 m y

233− -> pq schema0 schema1 m x

234− -> pq schema0 schema2 m y

236+ => pq schemas1 schemas2 m y

237+ -> pq schemas0 schemas1 m x

238+ -> pq schemas0 schemas2 m y

235239 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)

236240

237241 -- | indexed analog of `<=<`

238242 pqAndThen

239243 :: Monad m

240− => (y -> pq schema1 schema2 m z)

241− -> (x -> pq schema0 schema1 m y)

242− -> x -> pq schema0 schema2 m z

244+ => (y -> pq schemas1 schemas2 m z)

245+ -> (x -> pq schemas0 schemas1 m y)

246+ -> x -> pq schemas0 schemas2 m z

243247 pqAndThen g f x = pqBind g (f x)

244248

245− -- | Safely embed a computation in a larger schema.

246− pqEmbed

247− :: Monad m

248− => pq schema0 schema1 m x

249− -> pq (table ': schema0) (table : schema1) m x

250−

251− -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law

249+ -- | Run a `Definition` with `LibPQ.exec`.

252250 --

253− -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@

251+ -- It should be functorial in effect.

252+ --

253+ -- @define id = return ()@

254+ -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@

254255 define

255− :: MonadBase IO io

256− => Definition schema0 schema1

257− -> pq schema0 schema1 io (K LibPQ.Result '[])

256+ :: MonadIO io

257+ => Definition schemas0 schemas1

258+ -> pq schemas0 schemas1 io ()

258259

259260instance IndexedMonadTransPQ PQ where

260261

@@ -267,26 +268,26 @@ instance IndexedMonadTransPQ PQ where

267268 K x' <- x conn

268269 unPQ (f x') (K (unK conn))

269270

270− pqEmbed (PQ pq) = PQ $ \ (K conn) -> do

271− K x <- pq (K conn)

272− return $ K x

273−

274271 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do

275− resultMaybe <- liftBase $ LibPQ.exec conn q

272+ resultMaybe <- liftIO $ LibPQ.exec conn q

276273 case resultMaybe of

277274 Nothing -> throw $ ResultException

278275 "define: LibPQ.exec returned no results"

279− Just result -> return $ K (K result)

276+ Just result -> K <$> okResult_ result

280277

281−{- | `MonadPQ` is an `mtl` style constraint, similar to

282−`Control.Monad.State.Class.MonadState`, for using `LibPQ` to

278+{- | `MonadPQ` is an @mtl@ style constraint, similar to

279+`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to

283280

284281* `manipulateParams` runs a `Manipulation` with params from a type

285282 with a `ToParams` constraint. It calls `LibPQ.execParams` and

286283 doesn't afraid of anything.

287284

285+* `manipulateParams_` is like `manipulateParams` for a returning-free statement.

286+

288287* `manipulate` is like `manipulateParams` for a parameter-free statement.

289288

289+* `manipulate_` is like `manipulate` for a returning-free statement.

290+

290291* `runQueryParams` is like `manipulateParams` for query statements.

291292

292293* `runQuery` is like `runQueryParams` for a parameter-free statement.

@@ -300,11 +301,11 @@ instance IndexedMonadTransPQ PQ where

300301* `forPrepared` is a flipped `traversePrepared`

301302

302303* `traversePrepared_` is like `traversePrepared` but works on `Foldable`

303− containers and returns unit.

304+ containers for a returning-free statement.

304305

305306* `forPrepared_` is a flipped `traversePrepared_`.

306307

307−* `liftPQ` lets you lift actions from `LibPQ` that require a connection

308+* `liftPQ` lets you lift actions from `Database.PostgreSQL.LibPQ` that require a connection

308309 into your monad.

309310

310311To define an instance, you can minimally define only `manipulateParams`,

@@ -312,67 +313,77 @@ To define an instance, you can minimally define only `manipulateParams`,

312313a default instance.

313314

314315-}

315−class Monad pq => MonadPQ schema pq | pq -> schema where

316+class Monad pq => MonadPQ schemas pq | pq -> schemas where

316317 manipulateParams

317318 :: ToParams x params

318− => Manipulation schema params ys

319− -- ^ `insertRows`, `update` or `deleteFrom`

319+ => Manipulation '[] schemas params ys

320+ -- ^ `insertInto`, `update` or `deleteFrom`

320321 -> x -> pq (K LibPQ.Result ys)

321322 default manipulateParams

322− :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

323+ :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

323324 => ToParams x params

324− => Manipulation schema params ys

325− -- ^ `insertRows`, `update` or `deleteFrom`

325+ => Manipulation '[] schemas params ys

326+ -- ^ `insertInto`, `update` or `deleteFrom`

326327 -> x -> pq (K LibPQ.Result ys)

327328 manipulateParams manipulation params = lift $

328329 manipulateParams manipulation params

329330

330− manipulate :: Manipulation schema '[] ys -> pq (K LibPQ.Result ys)

331+ manipulateParams_

332+ :: ToParams x params

333+ => Manipulation '[] schemas params '[]

334+ -- ^ `insertInto`, `update` or `deleteFrom`

335+ -> x -> pq ()

336+ manipulateParams_ q x = void $ manipulateParams q x

337+

338+ manipulate :: Manipulation '[] schemas '[] ys -> pq (K LibPQ.Result ys)

331339 manipulate statement = manipulateParams statement ()

332340

341+ manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()

342+ manipulate_ = void . manipulate

343+

333344 runQueryParams

334345 :: ToParams x params

335− => Query schema params ys

346+ => Query '[] '[] schemas params ys

336347 -- ^ `select` and friends

337348 -> x -> pq (K LibPQ.Result ys)

338349 runQueryParams = manipulateParams . queryStatement

339350

340351 runQuery

341− :: Query schema '[] ys

352+ :: Query '[] '[] schemas '[] ys

342353 -- ^ `select` and friends

343354 -> pq (K LibPQ.Result ys)

344355 runQuery q = runQueryParams q ()

345356

346357 traversePrepared

347358 :: (ToParams x params, Traversable list)

348− => Manipulation schema params ys

349− -- ^ `insertRows`, `update`, or `deleteFrom`, and friends

359+ => Manipulation '[] schemas params ys

360+ -- ^ `insertInto`, `update`, or `deleteFrom`, and friends

350361 -> list x -> pq (list (K LibPQ.Result ys))

351362 default traversePrepared

352− :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

363+ :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

353364 => (ToParams x params, Traversable list)

354− => Manipulation schema params ys -> list x -> pq (list (K LibPQ.Result ys))

365+ => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))

355366 traversePrepared manipulation params = lift $

356367 traversePrepared manipulation params

357368

358369 forPrepared

359370 :: (ToParams x params, Traversable list)

360371 => list x

361− -> Manipulation schema params ys

362− -- ^ `insertRows`, `update` or `deleteFrom`

372+ -> Manipulation '[] schemas params ys

373+ -- ^ `insertInto`, `update` or `deleteFrom`

363374 -> pq (list (K LibPQ.Result ys))

364375 forPrepared = flip traversePrepared

365376

366377 traversePrepared_

367378 :: (ToParams x params, Foldable list)

368− => Manipulation schema params '[]

369− -- ^ `insertRows`, `update` or `deleteFrom`

379+ => Manipulation '[] schemas params '[]

380+ -- ^ `insertInto`, `update` or `deleteFrom`

370381 -> list x -> pq ()

371382 default traversePrepared_

372− :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

383+ :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

373384 => (ToParams x params, Foldable list)

374− => Manipulation schema params '[]

375− -- ^ `insertRows`, `update` or `deleteFrom`

385+ => Manipulation '[] schemas params '[]

386+ -- ^ `insertInto`, `update` or `deleteFrom`

376387 -> list x -> pq ()

377388 traversePrepared_ manipulation params = lift $

378389 traversePrepared_ manipulation params

@@ -380,45 +391,45 @@ class Monad pq => MonadPQ schema pq | pq -> schema where

380391 forPrepared_

381392 :: (ToParams x params, Foldable list)

382393 => list x

383− -> Manipulation schema params '[]

384− -- ^ `insertRows`, `update` or `deleteFrom`

394+ -> Manipulation '[] schemas params '[]

395+ -- ^ `insertInto`, `update` or `deleteFrom`

385396 -> pq ()

386397 forPrepared_ = flip traversePrepared_

387398

388399 liftPQ :: (LibPQ.Connection -> IO a) -> pq a

389400 default liftPQ

390− :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

401+ :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

391402 => (LibPQ.Connection -> IO a) -> pq a

392403 liftPQ = lift . liftPQ

393404

394−instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)

395− => MonadPQ schema (PQ schema0 schema1 io) where

405+instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)

406+ => MonadPQ schemas (PQ schemas0 schemas1 io) where

396407

397408 manipulateParams

398− (UnsafeManipulation q :: Manipulation schema ps ys) (params :: x) =

409+ (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =

399410 PQ $ \ (K conn) -> do

400411 let

401412 toParam' encoding =

402413 (LibPQ.invalidOid, encodingBytes encoding, LibPQ.Binary)

403414 params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))

404415 q' = q <> ";"

405− resultMaybe <- liftBase $ LibPQ.execParams conn q' params' LibPQ.Binary

416+ resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary

406417 case resultMaybe of

407418 Nothing -> throw $ ResultException

408419 "manipulateParams: LibPQ.execParams returned no results"

409420 Just result -> do

410− tryResult result

421+ okResult_ result

411422 return $ K (K result)

412423

413424 traversePrepared

414− (UnsafeManipulation q :: Manipulation schema xs ys) (list :: list x) =

415− PQ $ \ (K conn) -> liftBase $ do

425+ (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =

426+ PQ $ \ (K conn) -> liftIO $ do

416427 let temp = "temporary_statement"

417428 prepResultMaybe <- LibPQ.prepare conn temp q Nothing

418429 case prepResultMaybe of

419430 Nothing -> throw $ ResultException

420431 "traversePrepared: LibPQ.prepare returned no results"

421− Just prepResult -> tryResult prepResult

432+ Just prepResult -> okResult_ prepResult

422433 results <- for list $ \ params -> do

423434 let

424435 toParam' encoding = (encodingBytes encoding,LibPQ.Binary)

@@ -428,24 +439,24 @@ instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)

428439 Nothing -> throw $ ResultException

429440 "traversePrepared: LibPQ.execParams returned no results"

430441 Just result -> do

431− tryResult result

442+ okResult_ result

432443 return $ K result

433444 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

434445 case deallocResultMaybe of

435446 Nothing -> throw $ ResultException

436447 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

437− Just deallocResult -> tryResult deallocResult

448+ Just deallocResult -> okResult_ deallocResult

438449 return (K results)

439450

440451 traversePrepared_

441− (UnsafeManipulation q :: Manipulation schema xs '[]) (list :: list x) =

442− PQ $ \ (K conn) -> liftBase $ do

452+ (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =

453+ PQ $ \ (K conn) -> liftIO $ do

443454 let temp = "temporary_statement"

444455 prepResultMaybe <- LibPQ.prepare conn temp q Nothing

445456 case prepResultMaybe of

446457 Nothing -> throw $ ResultException

447458 "traversePrepared_: LibPQ.prepare returned no results"

448− Just prepResult -> tryResult prepResult

459+ Just prepResult -> okResult_ prepResult

449460 for_ list $ \ params -> do

450461 let

451462 toParam' encoding = (encodingBytes encoding, LibPQ.Binary)

@@ -454,82 +465,79 @@ instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)

454465 case resultMaybe of

455466 Nothing -> throw $ ResultException

456467 "traversePrepared_: LibPQ.execParams returned no results"

457− Just result -> tryResult result

468+ Just result -> okResult_ result

458469 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

459470 case deallocResultMaybe of

460471 Nothing -> throw $ ResultException

461472 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

462− Just deallocResult -> tryResult deallocResult

473+ Just deallocResult -> okResult_ deallocResult

463474 return (K ())

464475

465476 liftPQ pq = PQ $ \ (K conn) -> do

466− y <- liftBase $ pq conn

477+ y <- liftIO $ pq conn

467478 return (K y)

468479

469−instance MonadPQ schema m => MonadPQ schema (IdentityT m)

470−instance MonadPQ schema m => MonadPQ schema (ReaderT r m)

471−instance MonadPQ schema m => MonadPQ schema (Strict.StateT s m)

472−instance MonadPQ schema m => MonadPQ schema (Lazy.StateT s m)

473−instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.WriterT w m)

474−instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.WriterT w m)

475−instance MonadPQ schema m => MonadPQ schema (MaybeT m)

476−instance MonadPQ schema m => MonadPQ schema (ExceptT e m)

477−instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.RWST r w s m)

478−instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.RWST r w s m)

479−instance MonadPQ schema m => MonadPQ schema (ContT r m)

480−

481−instance (Monad m, schema0 ~ schema1)

482− => Applicative (PQ schema0 schema1 m) where

480+instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)

481+instance MonadPQ schemas m => MonadPQ schemas (ReaderT r m)

482+instance MonadPQ schemas m => MonadPQ schemas (Strict.StateT s m)

483+instance MonadPQ schemas m => MonadPQ schemas (Lazy.StateT s m)

484+instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.WriterT w m)

485+instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.WriterT w m)

486+instance MonadPQ schemas m => MonadPQ schemas (MaybeT m)

487+instance MonadPQ schemas m => MonadPQ schemas (ExceptT e m)

488+instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.RWST r w s m)

489+instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.RWST r w s m)

490+instance MonadPQ schemas m => MonadPQ schemas (ContT r m)

491+

492+instance (Monad m, schemas0 ~ schemas1)

493+ => Applicative (PQ schemas0 schemas1 m) where

483494 pure x = PQ $ \ _conn -> pure (K x)

484495 (<*>) = pqAp

485496

486−instance (Monad m, schema0 ~ schema1)

487− => Monad (PQ schema0 schema1 m) where

497+instance (Monad m, schemas0 ~ schemas1)

498+ => Monad (PQ schemas0 schemas1 m) where

488499 return = pure

489500 (>>=) = flip pqBind

490501

491−instance schema0 ~ schema1 => MFunctor (PQ schema0 schema1) where

502+instance (Monad m, schemas0 ~ schemas1)

503+ => Fail.MonadFail (PQ schemas0 schemas1 m) where

504+ fail = Fail.fail

505+

506+instance schemas0 ~ schemas1 => MFunctor (PQ schemas0 schemas1) where

492507 hoist f (PQ pq) = PQ (f . pq)

493508

494−instance schema0 ~ schema1 => MonadTrans (PQ schema0 schema1) where

509+instance schemas0 ~ schemas1 => MonadTrans (PQ schemas0 schemas1) where

495510 lift m = PQ $ \ _conn -> do

496511 x <- m

497512 return (K x)

498513

499−instance schema0 ~ schema1 => MMonad (PQ schema0 schema1) where

514+instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where

500515 embed f (PQ pq) = PQ $ \ conn -> do

501516 evalPQ (f (pq conn)) conn

502517

503−instance (MonadBase b m, schema0 ~ schema1)

504− => MonadBase b (PQ schema0 schema1 m) where

505− liftBase = lift . liftBase

518+instance (MonadIO m, schema0 ~ schema1)

519+ => MonadIO (PQ schema0 schema1 m) where

520+ liftIO = lift . liftIO

506521

507−-- | A snapshot of the state of a `PQ` computation.

508−type PQRun schema =

509− forall m x. Monad m => PQ schema schema m x -> m (K x schema)

510−

511−-- | Helper function in defining `MonadBaseControl` instance for `PQ`.

512−pqliftWith :: Functor m => (PQRun schema -> m a) -> PQ schema schema m a

513−pqliftWith f = PQ $ \ conn ->

514− fmap K (f $ \ pq -> unPQ pq conn)

515−

516−instance (MonadBaseControl b m, schema0 ~ schema1)

517− => MonadBaseControl b (PQ schema0 schema1 m) where

518− type StM (PQ schema0 schema1 m) x = StM m (K x schema0)

519− liftBaseWith f =

520− pqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

521− restoreM = PQ . const . restoreM

522+instance (MonadUnliftIO m, schemas0 ~ schemas1)

523+ => MonadUnliftIO (PQ schemas0 schemas1 m) where

524+ withRunInIO

525+ :: ((forall a . PQ schemas0 schema1 m a -> IO a) -> IO b)

526+ -> PQ schemas0 schema1 m b

527+ withRunInIO inner = PQ $ \conn ->

528+ withRunInIO $ \(run :: (forall x . m x -> IO x)) ->

529+ K <$> inner (\pq -> run $ unK <$> unPQ pq conn)

522530

523531-- | Get a row corresponding to a given row number from a `LibPQ.Result`,

524532-- throwing an exception if the row number is out of bounds.

525533getRow

526− :: (FromRow columns y, MonadBase IO io)

534+ :: (FromRow columns y, MonadIO io)

527535 => LibPQ.Row

528536 -- ^ row number

529537 -> K LibPQ.Result columns

530538 -- ^ result

531539 -> io y

532−getRow r (K result :: K LibPQ.Result columns) = liftBase $ do

540+getRow r (K result :: K LibPQ.Result columns) = liftIO $ do

533541 numRows <- LibPQ.ntuples result

534542 when (numRows < r) $ throw $ ResultException $

535543 "getRow: expected at least " <> pack (show r) <> "rows but only saw "

@@ -547,13 +555,13 @@ getRow r (K result :: K LibPQ.Result columns) = liftBase $ do

547555-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,

548556-- otherwise returning the row along with the next row number.

549557nextRow

550− :: (FromRow columns y, MonadBase IO io)

558+ :: (FromRow columns y, MonadIO io)

551559 => LibPQ.Row -- ^ total number of rows

552560 -> K LibPQ.Result columns -- ^ result

553561 -> LibPQ.Row -- ^ row number

554562 -> io (Maybe (LibPQ.Row,y))

555563nextRow total (K result :: K LibPQ.Result columns) r

556− = liftBase $ if r >= total then return Nothing else do

564+ = liftIO $ if r >= total then return Nothing else do

557565 let len = fromIntegral (lengthSList (Proxy @columns))

558566 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

559567 case fromList row' of

@@ -564,10 +572,10 @@ nextRow total (K result :: K LibPQ.Result columns) r

564572

565573-- | Get all rows from a `LibPQ.Result`.

566574getRows

567− :: (FromRow columns y, MonadBase IO io)

575+ :: (FromRow columns y, MonadIO io)

568576 => K LibPQ.Result columns -- ^ result

569577 -> io [y]

570−getRows (K result :: K LibPQ.Result columns) = liftBase $ do

578+getRows (K result :: K LibPQ.Result columns) = liftIO $ do

571579 let len = fromIntegral (lengthSList (Proxy @columns))

572580 numRows <- LibPQ.ntuples result

573581 for [0 .. numRows - 1] $ \ r -> do

@@ -580,10 +588,10 @@ getRows (K result :: K LibPQ.Result columns) = liftBase $ do

580588

581589-- | Get the first row if possible from a `LibPQ.Result`.

582590firstRow

583− :: (FromRow columns y, MonadBase IO io)

591+ :: (FromRow columns y, MonadIO io)

584592 => K LibPQ.Result columns -- ^ result

585593 -> io (Maybe y)

586−firstRow (K result :: K LibPQ.Result columns) = liftBase $ do

594+firstRow (K result :: K LibPQ.Result columns) = liftIO $ do

587595 numRows <- LibPQ.ntuples result

588596 if numRows <= 0 then return Nothing else do

589597 let len = fromIntegral (lengthSList (Proxy @columns))

@@ -596,23 +604,23 @@ firstRow (K result :: K LibPQ.Result columns) = liftBase $ do

596604

597605-- | Lifts actions on results from @LibPQ@.

598606liftResult

599− :: MonadBase IO io

607+ :: MonadIO io

600608 => (LibPQ.Result -> IO x)

601609 -> K LibPQ.Result results -> io x

602−liftResult f (K result) = liftBase $ f result

610+liftResult f (K result) = liftIO $ f result

603611

604612-- | Returns the number of rows (tuples) in the query result.

605−ntuples :: MonadBase IO io => K LibPQ.Result columns -> io LibPQ.Row

613+ntuples :: MonadIO io => K LibPQ.Result columns -> io LibPQ.Row

606614ntuples = liftResult LibPQ.ntuples

607615

608616-- | Returns the result status of the command.

609−resultStatus :: MonadBase IO io => K LibPQ.Result results -> io LibPQ.ExecStatus

617+resultStatus :: MonadIO io => K LibPQ.Result results -> io LibPQ.ExecStatus

610618resultStatus = liftResult LibPQ.resultStatus

611619

612620-- | Returns the error message most recently generated by an operation

613621-- on the connection.

614622resultErrorMessage

615− :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)

623+ :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)

616624resultErrorMessage = liftResult LibPQ.resultErrorMessage

617625

618626-- | Returns the error code most recently generated by an operation

@@ -620,29 +628,29 @@ resultErrorMessage = liftResult LibPQ.resultErrorMessage

620628--

621629-- https://www.postgresql.org/docs/current/static/errcodes-appendix.html

622630resultErrorCode

623− :: MonadBase IO io

631+ :: MonadIO io

624632 => K LibPQ.Result results

625633 -> io (Maybe ByteString)

626634resultErrorCode = liftResult (flip LibPQ.resultErrorField LibPQ.DiagSqlstate)

627635

628−-- | `Exception`s that can be thrown by Squeal.

629−data SquealException

630− = PQException

636+-- | the state of LibPQ

637+data PQState = PQState

631638 { sqlExecStatus :: LibPQ.ExecStatus

632639 , sqlStateCode :: Maybe ByteString

633640 -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html

634641 , sqlErrorMessage :: Maybe ByteString

635− }

642+ } deriving (Eq, Show)

643+

644+-- | `Exception`s that can be thrown by Squeal.

645+data SquealException

646+ = PQException PQState

636647 | ResultException Text

637648 | ParseException Text

638649 deriving (Eq, Show)

639650instance Exception SquealException

640651

641−tryResult

642− :: MonadBase IO io

643− => LibPQ.Result

644− -> io ()

645−tryResult result = liftBase $ do

652+okResult_ :: MonadIO io => LibPQ.Result -> io ()

653+okResult_ result = liftIO $ do

646654 status <- LibPQ.resultStatus result

647655 case status of

648656 LibPQ.CommandOk -> return ()

@@ -650,11 +658,16 @@ tryResult result = liftBase $ do

650658 _ -> do

651659 stateCode <- LibPQ.resultErrorField result LibPQ.DiagSqlstate

652660 msg <- LibPQ.resultErrorMessage result

653− throw $ PQException status stateCode msg

661+ throw . PQException $ PQState status stateCode msg

662+

663+-- | Check if a `LibPQ.Result`'s status is either `LibPQ.CommandOk`

664+-- or `LibPQ.TuplesOk` otherwise `throw` a `PQException`.

665+okResult :: MonadIO io => K LibPQ.Result row -> io ()

666+okResult = okResult_ . unK

654667

655668-- | Catch `SquealException`s.

656669catchSqueal

657− :: MonadBaseControl IO io

670+ :: MonadUnliftIO io

658671 => io a

659672 -> (SquealException -> io a) -- ^ handler

660673 -> io a

@@ -662,7 +675,14 @@ catchSqueal = catch

662675

663676-- | Handle `SquealException`s.

664677handleSqueal

665− :: MonadBaseControl IO io

678+ :: MonadUnliftIO io

666679 => (SquealException -> io a) -- ^ handler

667680 -> io a -> io a

668681handleSqueal = handle

682+

683+-- | `Either` return a `SquealException` or a result.

684+trySqueal

685+ :: MonadUnliftIO io

686+ => io a

687+ -> io (Either SquealException a)

688+trySqueal = try

squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+54−53

@@ -12,6 +12,7 @@ A `MonadPQ` for pooled connections.

1212 DeriveFunctor

1313 , FlexibleContexts

1414 , FlexibleInstances

15+ , InstanceSigs

1516 , MultiParamTypeClasses

1617 , RankNTypes

1718 , ScopedTypeVariables

@@ -26,51 +27,52 @@ module Squeal.PostgreSQL.Pool

2627 , createConnectionPool

2728 , Pool

2829 , destroyAllResources

29− , PoolPQRun

30− , poolpqliftWith

3130 ) where

3231

33−import Control.Monad.Base

3432import Control.Monad.Trans

35−import Control.Monad.Trans.Control

3633import Data.ByteString

37−import Data.Pool

3834import Data.Time

3935import Generics.SOP (K(..))

36+import UnliftIO (MonadUnliftIO (..))

37+import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)

38+

39+import qualified Control.Monad.Fail as Fail

4040

4141import Squeal.PostgreSQL.PQ

4242import Squeal.PostgreSQL.Schema

4343

44−{- | `PoolPQ` @schema@ should be a drop-in replacement for `PQ` @schema schema@.

44+{- | `PoolPQ` @schemas@ should be a drop-in replacement for `PQ` @schemas schemas@.

4545

4646Typical use case would be to create your pool using `createConnectionPool` and run anything that requires the pool connection with it.

4747

4848Here's a simplified example:

4949

50−> type Schema = '[ "tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint2])]

51−>

52−> someQuery :: Manipulation Schema '[ 'NotNull 'PGint2] '[]

53−> someQuery = insertRow #tab

54−> (Set (param @1) `As` #col :* Nil)

55−> OnConflictDoNothing (Returning Nil)

56−>

57−> insertOne :: (MonadBaseControl IO m, MonadPQ Schema m) => m ()

58−> insertOne = void $ manipulateParams someQuery . Only $ (1 :: Int16)

59−>

60−> insertOneInPool :: ByteString -> IO ()

61−> insertOneInPool connectionString = do

62−> pool <- createConnectionPool connectionString 1 0.5 10

63−> liftIO $ runPoolPQ (insertOne) pool

64−

50+>>> import Squeal.PostgreSQL

51+>>> :{

52+do

53+ let

54+ query :: Query_ (Public '[]) () (Only Char)

55+ query = values_ $ literal 'a' `as` #fromOnly

56+ session :: PoolPQ (Public '[]) IO Char

57+ session = do

58+ result <- runQuery query

59+ Just (Only chr) <- firstRow result

60+ return chr

61+ pool <- createConnectionPool "host=localhost port=5432 dbname=exampledb" 1 0.5 10

62+ chr <- runPoolPQ session pool

63+ destroyAllResources pool

64+ putChar chr

65+:}

66+a

6567-}

66−newtype PoolPQ (schema :: SchemaType) m x =

67− PoolPQ { runPoolPQ :: Pool (K Connection schema) -> m x }

68+newtype PoolPQ (schemas :: SchemasType) m x =

69+ PoolPQ { runPoolPQ :: Pool (K Connection schemas) -> m x }

6870 deriving Functor

6971

7072-- | Create a striped pool of connections.

7173-- 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.

7274createConnectionPool

73− :: MonadBase IO io

75+ :: MonadUnliftIO io

7476 => ByteString

7577 -- ^ The passed string can be empty to use all default parameters, or it can

7678 -- contain one or more parameter settings separated by whitespace.

@@ -86,12 +88,12 @@ createConnectionPool

8688 -> Int

8789 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.

8890 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.

89− -> io (Pool (K Connection schema))

90−createConnectionPool conninfo stripes idle maxResrc = liftBase $

91+ -> io (Pool (K Connection schemas))

92+createConnectionPool conninfo stripes idle maxResrc =

9193 createPool (connectdb conninfo) finish stripes idle maxResrc

9294

9395-- | `Applicative` instance for `PoolPQ`.

94−instance Monad m => Applicative (PoolPQ schema m) where

96+instance Monad m => Applicative (PoolPQ schemas m) where

9597 pure x = PoolPQ $ \ _ -> pure x

9698 PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do

9799 f' <- f pool

@@ -99,55 +101,54 @@ instance Monad m => Applicative (PoolPQ schema m) where

99101 return $ f' x'

100102

101103-- | `Monad` instance for `PoolPQ`.

102−instance Monad m => Monad (PoolPQ schema m) where

104+instance Monad m => Monad (PoolPQ schemas m) where

103105 return = pure

104106 PoolPQ x >>= f = PoolPQ $ \ pool -> do

105107 x' <- x pool

106108 runPoolPQ (f x') pool

107109

110+-- | `Fail.MonadFail` instance for `PoolPQ`.

111+instance Monad m => Fail.MonadFail (PoolPQ schemas m) where

112+ fail = Fail.fail

113+

108114-- | `MonadTrans` instance for `PoolPQ`.

109−instance MonadTrans (PoolPQ schema) where

115+instance MonadTrans (PoolPQ schemas) where

110116 lift m = PoolPQ $ \ _pool -> m

111117

112−-- | `MonadBase` instance for `PoolPQ`.

113−instance MonadBase b m => MonadBase b (PoolPQ schema m) where

114− liftBase = lift . liftBase

115−

116118-- | `MonadPQ` instance for `PoolPQ`.

117−instance MonadBaseControl IO io => MonadPQ schema (PoolPQ schema io) where

119+instance MonadUnliftIO io => MonadPQ schemas (PoolPQ schemas io) where

118120 manipulateParams manipulation params = PoolPQ $ \ pool -> do

119121 withResource pool $ \ conn -> do

120− (K result :: K (K Result ys) schema) <- flip unPQ conn $

122+ (K result :: K (K Result ys) schemas) <- flip unPQ conn $

121123 manipulateParams manipulation params

122124 return result

123125 traversePrepared manipulation params = PoolPQ $ \ pool ->

124126 withResource pool $ \ conn -> do

125− (K result :: K (list (K Result ys)) schema) <- flip unPQ conn $

127+ (K result :: K (list (K Result ys)) schemas) <- flip unPQ conn $

126128 traversePrepared manipulation params

127129 return result

128130 traversePrepared_ manipulation params = PoolPQ $ \ pool -> do

129131 withResource pool $ \ conn -> do

130− (_ :: K () schema) <- flip unPQ conn $

132+ (_ :: K () schemas) <- flip unPQ conn $

131133 traversePrepared_ manipulation params

132134 return ()

133135 liftPQ m = PoolPQ $ \ pool ->

134136 withResource pool $ \ conn -> do

135− (K result :: K result schema) <- flip unPQ conn $

137+ (K result :: K result schemas) <- flip unPQ conn $

136138 liftPQ m

137139 return result

138140

139−-- | A snapshot of the state of a `PoolPQ` computation.

140−type PoolPQRun schema =

141− forall m x. Monad m => PoolPQ schema m x -> m x

142−

143−-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.

144−poolpqliftWith :: Functor m => (PoolPQRun schema -> m a) -> PoolPQ schema m a

145−poolpqliftWith f = PoolPQ $ \ pool ->

146− (f $ \ pq -> runPoolPQ pq pool)

147−

148−-- | `MonadBaseControl` instance for `PoolPQ`.

149−instance MonadBaseControl b m => MonadBaseControl b (PoolPQ schema m) where

150− type StM (PoolPQ schema m) x = StM m x

151− liftBaseWith f =

152− poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

153− restoreM = PoolPQ . const . restoreM

141+-- | 'MonadIO' instance for 'PoolPQ'.

142+instance (MonadIO m)

143+ => MonadIO (PoolPQ schemas m) where

144+ liftIO = lift . liftIO

145+

146+-- | 'MonadUnliftIO' instance for 'PoolPQ'.

147+instance (MonadUnliftIO m)

148+ => MonadUnliftIO (PoolPQ schemas m) where

149+ withRunInIO

150+ :: ((forall a . PoolPQ schemas m a -> IO a) -> IO b)

151+ -> PoolPQ schemas m b

152+ withRunInIO inner = PoolPQ $ \pool ->

153+ withRunInIO $ \(run :: (forall x . m x -> IO x)) ->

154+ inner (\poolpq -> run $ runPoolPQ poolpq pool)

squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+543−911

@@ -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

@@ -17,8 +17,12 @@ Squeal queries.

1717 , GeneralizedNewtypeDeriving

1818 , LambdaCase

1919 , MultiParamTypeClasses

20+ , OverloadedLabels

2021 , OverloadedStrings

22+ , QuantifiedConstraints

23+ , ScopedTypeVariables

2124 , StandaloneDeriving

25+ , TypeApplications

2226 , TypeFamilies

2327 , TypeInType

2428 , TypeOperators

@@ -28,14 +32,14 @@ Squeal queries.

2832

2933module Squeal.PostgreSQL.Query

3034 ( -- * Queries

31− Query (UnsafeQuery, renderQuery)

35+ Query_

36+ , Query (..)

3237 -- ** Select

3338 , select

39+ , select_

3440 , selectDistinct

35− , selectStar

36− , selectDistinctStar

37− , selectDotStar

38− , selectDistinctDotStar

41+ , selectDistinct_

42+ , Selection (..)

3943 -- ** Values

4044 , values

4145 , values_

@@ -47,33 +51,15 @@ module Squeal.PostgreSQL.Query

4751 , except

4852 , exceptAll

4953 -- ** With

50− , With (with)

54+ , With (..)

5155 , CommonTableExpression (..)

52− , renderCommonTableExpression

53− , renderCommonTableExpressions

54− -- ** Json

55− , jsonEach

56− , jsonbEach

57− , jsonEachAsText

58− , jsonbEachAsText

59− , jsonObjectKeys

60− , jsonbObjectKeys

61− , jsonPopulateRecord

62− , jsonbPopulateRecord

63− , jsonPopulateRecordSet

64− , jsonbPopulateRecordSet

65− , jsonToRecord

66− , jsonbToRecord

67− , jsonToRecordSet

68− , jsonbToRecordSet

56+ , withRecursive

6957 -- * Table Expressions

7058 , TableExpression (..)

71− , renderTableExpression

7259 , from

7360 , where_

7461 , groupBy

7562 , having

76− , orderBy

7763 , limit

7864 , offset

7965 -- * From Clauses

@@ -81,52 +67,21 @@ module Squeal.PostgreSQL.Query

8167 , table

8268 , subquery

8369 , view

70+ , common

8471 , crossJoin

8572 , innerJoin

8673 , leftOuterJoin

8774 , rightOuterJoin

8875 , fullOuterJoin

8976 -- * Grouping

90− , By (By1, By2)

91− , renderBy

92− , GroupByClause (NoGroups, Group)

93− , renderGroupByClause

94− , HavingClause (NoHaving, Having)

95− , renderHavingClause

96− -- * Sorting

97− , SortExpression (..)

98− , renderSortExpression

99− -- * Subquery Expressions

100− , in_

101− , rowIn

102− , eqAll

103− , rowEqAll

104− , eqAny

105− , rowEqAny

106− , neqAll

107− , rowNeqAll

108− , neqAny

109− , rowNeqAny

110− , allLt

111− , rowLtAll

112− , ltAny

113− , rowLtAny

114− , lteAll

115− , rowLteAll

116− , lteAny

117− , rowLteAny

118− , gtAll

119− , rowGtAll

120− , gtAny

121− , rowGtAny

122− , gteAll

123− , rowGteAll

124− , gteAny

125− , rowGteAny

77+ , By (..)

78+ , GroupByClause (..)

79+ , HavingClause (..)

12680 ) where

12781

12882import Control.DeepSeq

12983import Data.ByteString (ByteString)

84+import Data.Kind (Type)

13085import Data.String

13186import Data.Word

13287import Generics.SOP hiding (from)

@@ -134,23 +89,77 @@ import GHC.TypeLits

13489

13590import qualified GHC.Generics as GHC

13691

92+import Squeal.PostgreSQL.Alias

13793import Squeal.PostgreSQL.Expression

94+import Squeal.PostgreSQL.Expression.Logic

95+import Squeal.PostgreSQL.Expression.Sort

96+import Squeal.PostgreSQL.Expression.Window

97+import Squeal.PostgreSQL.List

98+import Squeal.PostgreSQL.PG

13899import Squeal.PostgreSQL.Render

139100import Squeal.PostgreSQL.Schema

140101

102+-- $setup

103+-- >>> import Squeal.PostgreSQL

104+-- >>> import Data.Int (Int32, Int64)

105+-- >>> import Data.Monoid (Sum (..))

106+-- >>> import Data.Text (Text)

107+-- >>> import qualified Generics.SOP as SOP

108+

109+{- |

110+The process of retrieving or the command to retrieve data from

111+a database is called a `Query`.

112+

113+The general `Query` type is parameterized by

114+

115+* @outer :: FromType@ - outer scope for a correlated subquery,

116+* @commons :: FromType@ - scope for all `common` table expressions,

117+* @schemas :: SchemasType@ - scope for all `table`s and `view`s,

118+* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,

119+* @row :: RowType@ - return type of the `Query`.

120+-}

121+newtype Query

122+ (outer :: FromType)

123+ (commons :: FromType)

124+ (schemas :: SchemasType)

125+ (params :: [NullityType])

126+ (row :: RowType)

127+ = UnsafeQuery { renderQuery :: ByteString }

128+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

129+instance RenderSQL (Query outer commons schemas params row) where renderSQL = renderQuery

130+

141131{- |

142−The process of retrieving or the command to retrieve data from a database

143−is called a `Query`. Let's see some examples of queries.

132+The top level `Query_` type is parameterized by a @schemas@ `SchemasType`,

133+against which the query is type-checked, an input @parameters@ Haskell `Type`,

134+and an ouput row Haskell `Type`.

135+

136+A top-level query can be run

137+using `Squeal.PostgreSQL.PQ.runQueryParams`, or if @parameters = ()@

138+using `Squeal.PostgreSQL.PQ.runQuery`.

139+

140+Generally, @parameters@ will be a Haskell tuple or record whose entries

141+may be referenced using positional

142+`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a

143+Haskell record or a generalized record using tuples of `P` types and normal Haskell

144+records, whose entries will be targeted using overloaded labels.

145+

146+Let's see some examples of queries.

147+

148+>>> :set -XDeriveAnyClass -XDerivingStrategies

149+>>> :{

150+data Row a b = Row { col1 :: a, col2 :: b }

151+ deriving stock (GHC.Generic)

152+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

153+:}

144154

145155simple query:

146156

157+>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]

158+>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

147159>>> :{

148160let

149− query :: Query

150− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

151− '[]

152− '["col" ::: 'Null 'PGint4]

153− query = selectStar (from (table #tab))

161+ query :: Query_ (Public Schema) () (Row Int32 Int32)

162+ query = select Star (from (table #tab))

154163in printSQL query

155164:}

156165SELECT * FROM "tab" AS "tab"

@@ -159,34 +168,22 @@ restricted query:

159168

160169>>> :{

161170let

162− query :: Query

163− '[ "tab" ::: 'Table ('[] :=>

164− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

165− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

166− '[]

167− '[ "sum" ::: 'NotNull 'PGint4

168− , "col1" ::: 'NotNull 'PGint4 ]

171+ query :: Query_ (Public Schema) () (Row Int32 Int32)

169172 query =

170− select

171− ((#col1 + #col2) `as` #sum :* #col1)

173+ select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)

172174 ( from (table #tab)

173175 & where_ (#col1 .> #col2)

174176 & where_ (#col2 .> 0) )

175177in printSQL query

176178:}

177−SELECT ("col1" + "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))

179+SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))

178180

179181subquery:

180182

181183>>> :{

182184let

183− query :: Query

184− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

185− '[]

186− '["col" ::: 'Null 'PGint4]

187− query =

188− selectStar

189− (from (subquery (selectStar (from (table #tab)) `as` #sub)))

185+ query :: Query_ (Public Schema) () (Row Int32 Int32)

186+ query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))

190187in printSQL query

191188:}

192189SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"

@@ -195,12 +192,8 @@ limits and offsets:

195192

196193>>> :{

197194let

198− query :: Query

199− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

200− '[]

201− '["col" ::: 'Null 'PGint4]

202− query = selectStar

203− (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)

195+ query :: Query_ (Public Schema) () (Row Int32 Int32)

196+ query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)

204197in printSQL query

205198:}

206199SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4

@@ -209,85 +202,80 @@ parameterized query:

209202

210203>>> :{

211204let

212− query :: Query

213− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGfloat8])]

214− '[ 'NotNull 'PGfloat8]

215− '["col" ::: 'NotNull 'PGfloat8]

216− query = selectStar

217− (from (table #tab) & where_ (#col .> param @1))

205+ query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)

206+ query = select Star (from (table #tab) & where_ (#col1 .> param @1))

218207in printSQL query

219208:}

220−SELECT * FROM "tab" AS "tab" WHERE ("col" > ($1 :: float8))

209+SELECT * FROM "tab" AS "tab" WHERE ("col1" > ($1 :: int4))

221210

222211aggregation query:

223212

224213>>> :{

225214let

226− query :: Query

227− '[ "tab" ::: 'Table ('[] :=>

228− '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

229− , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

230− '[]

231− '[ "sum" ::: 'NotNull 'PGint4

232− , "col1" ::: 'NotNull 'PGint4 ]

215+ query :: Query_ (Public Schema) () (Row Int32 Int32)

233216 query =

234− select (sum_ #col2 `as` #sum :* #col1)

217+ select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)

235218 ( from (table (#tab `as` #table1))

236219 & groupBy #col1

237− & having (#col1 + sum_ #col2 .> 1) )

220+ & having (#col1 + (fromNull 0 (sum_ (Distinct #col2))) .> 1) )

238221in printSQL query

239222:}

240−SELECT sum("col2") AS "sum", "col1" AS "col1" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + sum("col2")) > 1)

223+SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + COALESCE(sum(DISTINCT "col2"), 0)) > 1)

241224

242225sorted query:

243226

244227>>> :{

245228let

246− query :: Query

247− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

248− '[]

249− '["col" ::: 'Null 'PGint4]

250− query = selectStar

251− (from (table #tab) & orderBy [#col & AscNullsFirst])

229+ query :: Query_ (Public Schema) () (Row Int32 Int32)

230+ query = select Star (from (table #tab) & orderBy [#col1 & Asc])

252231in printSQL query

253232:}

254−SELECT * FROM "tab" AS "tab" ORDER BY "col" ASC NULLS FIRST

233+SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC

255234

256235joins:

257236

258−>>> :set -XFlexibleContexts

237+>>> :{

238+type OrdersColumns =

239+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

240+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

241+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

242+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4 ]

243+:}

244+

245+>>> :{

246+type OrdersConstraints =

247+ '["pk_orders" ::: PrimaryKey '["id"]

248+ ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]

249+ ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"] ]

250+:}

251+

252+>>> type NamesColumns = '["id" ::: 'NoDef :=> 'NotNull 'PGint4, "name" ::: 'NoDef :=> 'NotNull 'PGtext]

253+>>> type CustomersConstraints = '["pk_customers" ::: PrimaryKey '["id"]]

254+>>> type ShippersConstraints = '["pk_shippers" ::: PrimaryKey '["id"]]

255+>>> :{

256+type OrdersSchema =

257+ '[ "orders" ::: 'Table (OrdersConstraints :=> OrdersColumns)

258+ , "customers" ::: 'Table (CustomersConstraints :=> NamesColumns)

259+ , "shippers" ::: 'Table (ShippersConstraints :=> NamesColumns) ]

260+:}

261+

262+>>> :{

263+data Order = Order

264+ { price :: Float

265+ , customerName :: Text

266+ , shipperName :: Text

267+ } deriving GHC.Generic

268+instance SOP.Generic Order

269+instance SOP.HasDatatypeInfo Order

270+:}

271+

259272>>> :{

260273let

261− query :: Query

262− '[ "orders" ::: 'Table (

263− '["pk_orders" ::: PrimaryKey '["id"]

264− ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]

265− ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"]] :=>

266− '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

267− , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

268− , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

269− , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4

270− ])

271− , "customers" ::: 'Table (

272− '["pk_customers" ::: PrimaryKey '["id"]] :=>

273− '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

274− , "name" ::: 'NoDef :=> 'NotNull 'PGtext

275− ])

276− , "shippers" ::: 'Table (

277− '["pk_shippers" ::: PrimaryKey '["id"]] :=>

278− '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

279− , "name" ::: 'NoDef :=> 'NotNull 'PGtext

280− ])

281− ]

282− '[]

283− '[ "order_price" ::: 'NotNull 'PGfloat4

284− , "customer_name" ::: 'NotNull 'PGtext

285− , "shipper_name" ::: 'NotNull 'PGtext

286− ]

287− query = select

288− ( #o ! #price `as` #order_price :*

289− #c ! #name `as` #customer_name :*

290− #s ! #name `as` #shipper_name )

274+ query :: Query_ (Public OrdersSchema) () Order

275+ query = select_

276+ ( #o ! #price `as` #price :*

277+ #c ! #name `as` #customerName :*

278+ #s ! #name `as` #shipperName )

291279 ( from (table (#orders `as` #o)

292280 & innerJoin (table (#customers `as` #c))

293281 (#o ! #customer_id .== #c ! #id)

@@ -295,17 +283,15 @@ let

295283 (#o ! #shipper_id .== #s ! #id)) )

296284in printSQL query

297285:}

298−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")

286+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")

299287

300288self-join:

301289

302290>>> :{

303291let

304− query :: Query

305− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

306− '[]

307− '["col" ::: 'Null 'PGint4]

308− query = selectDotStar #t1

292+ query :: Query_ (Public Schema) () (Row Int32 Int32)

293+ query = select

294+ (#t1 & DotStar)

309295 (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))

310296in printSQL query

311297:}

@@ -315,24 +301,20 @@ value queries:

315301

316302>>> :{

317303let

318− query :: Query '[] '[] '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

319− query = values (1 `as` #foo :* true `as` #bar) [2 `as` #foo :* false `as` #bar]

304+ query :: Query_ schemas () (Row String Bool)

305+ query = values

306+ ("true" `as` #col1 :* true `as` #col2)

307+ ["false" `as` #col1 :* false `as` #col2]

320308in printSQL query

321309:}

322−SELECT * FROM (VALUES (1, TRUE), (2, FALSE)) AS t ("foo", "bar")

310+SELECT * FROM (VALUES (E'true', TRUE), (E'false', FALSE)) AS t ("col1", "col2")

323311

324312set operations:

325313

326314>>> :{

327315let

328− query :: Query

329− '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

330− '[]

331− '["col" ::: 'Null 'PGint4]

332− query =

333− selectStar (from (table #tab))

334− `unionAll`

335− selectStar (from (table #tab))

316+ query :: Query_ (Public Schema) () (Row Int32 Int32)

317+ query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))

336318in printSQL query

337319:}

338320(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")

@@ -341,173 +323,256 @@ with queries:

341323

342324>>> :{

343325let

344− query :: Query

345− '[ "t1" ::: 'View

346− '[ "c1" ::: 'NotNull 'PGtext

347− , "c2" ::: 'NotNull 'PGtext] ]

348− '[]

349− '[ "c1" ::: 'NotNull 'PGtext

350− , "c2" ::: 'NotNull 'PGtext ]

326+ query :: Query_ (Public Schema) () (Row Int32 Int32)

351327 query = with (

352− selectStar (from (view #t1)) `as` #t2 :>>

353− selectStar (from (view #t2)) `as` #t3

354− ) (selectStar (from (view #t3)))

328+ select Star (from (table #tab)) `as` #cte1 :>>

329+ select Star (from (common #cte1)) `as` #cte2

330+ ) (select Star (from (common #cte2)))

331+in printSQL query

332+:}

333+WITH "cte1" AS (SELECT * FROM "tab" AS "tab"), "cte2" AS (SELECT * FROM "cte1" AS "cte1") SELECT * FROM "cte2" AS "cte2"

334+

335+window function queries

336+

337+>>> :{

338+let

339+ query :: Query_ (Public Schema) () (Row Int32 Int64)

340+ query = select

341+ (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))

342+ (from (table #tab))

343+in printSQL query

344+:}

345+SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "col2" FROM "tab" AS "tab"

346+

347+correlated subqueries

348+

349+>>> :{

350+let

351+ query :: Query_ (Public Schema) () (Only Int32)

352+ query =

353+ select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))

354+ & where_ (exists (

355+ select Star (from (table (#tab `as` #t2))

356+ & where_ (#t2 ! #col2 .== #t1 ! #col1)))))

355357in printSQL query

356358:}

357−WITH "t2" AS (SELECT * FROM "t1" AS "t1"), "t3" AS (SELECT * FROM "t2" AS "t2") SELECT * FROM "t3" AS "t3"

359+SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))

360+

358361-}

359−newtype Query

360− (schema :: SchemaType)

361− (params :: [NullityType])

362− (columns :: RowType)

363− = UnsafeQuery { renderQuery :: ByteString }

364− deriving (GHC.Generic,Show,Eq,Ord,NFData)

365−instance RenderSQL (Query schema params columns) where renderSQL = renderQuery

362+type family Query_

363+ (schemas :: SchemasType)

364+ (parameters :: Type)

365+ (row :: Type) where

366+ Query_ schemas params row =

367+ Query '[] '[] schemas (TuplePG params) (RowPG row)

366368

367369-- | The results of two queries can be combined using the set operation

368370-- `union`. Duplicate rows are eliminated.

369371union

370− :: Query schema params columns

371− -> Query schema params columns

372− -> Query schema params columns

372+ :: Query outer commons schemas params columns

373+ -> Query outer commons schemas params columns

374+ -> Query outer commons schemas params columns

373375q1 `union` q2 = UnsafeQuery $

374− parenthesized (renderQuery q1)

376+ parenthesized (renderSQL q1)

375377 <+> "UNION"

376− <+> parenthesized (renderQuery q2)

378+ <+> parenthesized (renderSQL q2)

377379

378380-- | The results of two queries can be combined using the set operation

379381-- `unionAll`, the disjoint union. Duplicate rows are retained.

380382unionAll

381− :: Query schema params columns

382− -> Query schema params columns

383− -> Query schema params columns

383+ :: Query outer commons schemas params columns

384+ -> Query outer commons schemas params columns

385+ -> Query outer commons schemas params columns

384386q1 `unionAll` q2 = UnsafeQuery $

385− parenthesized (renderQuery q1)

387+ parenthesized (renderSQL q1)

386388 <+> "UNION" <+> "ALL"

387− <+> parenthesized (renderQuery q2)

389+ <+> parenthesized (renderSQL q2)

388390

389391-- | The results of two queries can be combined using the set operation

390392-- `intersect`, the intersection. Duplicate rows are eliminated.

391393intersect

392− :: Query schema params columns

393− -> Query schema params columns

394− -> Query schema params columns

394+ :: Query outer commons schemas params columns

395+ -> Query outer commons schemas params columns

396+ -> Query outer commons schemas params columns

395397q1 `intersect` q2 = UnsafeQuery $

396− parenthesized (renderQuery q1)

398+ parenthesized (renderSQL q1)

397399 <+> "INTERSECT"

398− <+> parenthesized (renderQuery q2)

400+ <+> parenthesized (renderSQL q2)

399401

400402-- | The results of two queries can be combined using the set operation

401403-- `intersectAll`, the intersection. Duplicate rows are retained.

402404intersectAll

403− :: Query schema params columns

404− -> Query schema params columns

405− -> Query schema params columns

405+ :: Query outer commons schemas params columns

406+ -> Query outer commons schemas params columns

407+ -> Query outer commons schemas params columns

406408q1 `intersectAll` q2 = UnsafeQuery $

407− parenthesized (renderQuery q1)

409+ parenthesized (renderSQL q1)

408410 <+> "INTERSECT" <+> "ALL"

409− <+> parenthesized (renderQuery q2)

411+ <+> parenthesized (renderSQL q2)

410412

411413-- | The results of two queries can be combined using the set operation

412414-- `except`, the set difference. Duplicate rows are eliminated.

413415except

414− :: Query schema params columns

415− -> Query schema params columns

416− -> Query schema params columns

416+ :: Query outer commons schemas params columns

417+ -> Query outer commons schemas params columns

418+ -> Query outer commons schemas params columns

417419q1 `except` q2 = UnsafeQuery $

418− parenthesized (renderQuery q1)

420+ parenthesized (renderSQL q1)

419421 <+> "EXCEPT"

420− <+> parenthesized (renderQuery q2)

422+ <+> parenthesized (renderSQL q2)

421423

422424-- | The results of two queries can be combined using the set operation

423425-- `exceptAll`, the set difference. Duplicate rows are retained.

424426exceptAll

425− :: Query schema params columns

426− -> Query schema params columns

427− -> Query schema params columns

427+ :: Query outer commons schemas params columns

428+ -> Query outer commons schemas params columns

429+ -> Query outer commons schemas params columns

428430q1 `exceptAll` q2 = UnsafeQuery $

429− parenthesized (renderQuery q1)

431+ parenthesized (renderSQL q1)

430432 <+> "EXCEPT" <+> "ALL"

431− <+> parenthesized (renderQuery q2)

433+ <+> parenthesized (renderSQL q2)

432434

433435{-----------------------------------------

434436SELECT queries

435437-----------------------------------------}

436438

439+{- | The simplest kinds of `Selection` are `Star` and `DotStar` which

440+emits all columns that a `TableExpression` produces. A select `List`

441+is a list of `Expression`s. A `Selection` could be a list of

442+`WindowFunction`s `Over` `WindowDefinition`. `Additional` `Selection`s can

443+be selected with `Also`.

444+-}

445+data Selection outer commons grp schemas params from row where

446+ Star

447+ :: HasUnique tab from row

448+ => Selection outer commons 'Ungrouped schemas params from row

449+ -- ^ `HasUnique` table in the `FromClause`

450+ DotStar

451+ :: Has tab from row

452+ => Alias tab

453+ -- ^ `Has` table with `Alias`

454+ -> Selection outer commons 'Ungrouped schemas params from row

455+ List

456+ :: SListI row

457+ => NP (Aliased (Expression outer commons grp schemas params from)) row

458+ -- ^ `NP` list of `Aliased` `Expression`s

459+ -> Selection outer commons grp schemas params from row

460+ Over

461+ :: SListI row

462+ => NP (Aliased (WindowFunction outer commons grp schemas params from)) row

463+ -- ^ `NP` list of `Aliased` `WindowFunction`s

464+ -> WindowDefinition outer commons grp schemas params from

465+ -> Selection outer commons grp schemas params from row

466+ Also

467+ :: Selection outer commons grp schemas params from right

468+ -- ^ `Additional` `Selection`

469+ -> Selection outer commons grp schemas params from left

470+ -> Selection outer commons grp schemas params from (Join left right)

471+instance Additional (Selection outer commons grp schemas params from) where

472+ also = Also

473+instance (KnownSymbol col, row ~ '[col ::: ty])

474+ => Aliasable col

475+ (Expression outer commons grp schemas params from ty)

476+ (Selection outer commons grp schemas params from row) where

477+ expr `as` col = List (expr `as` col)

478+instance (Has tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

479+ => IsQualified tab col

480+ (Selection outer commons 'Ungrouped schemas params from row1) where

481+ tab ! col = tab ! col `as` col

482+instance

483+ ( Has tab (Join outer from) row0

484+ , Has col row0 ty

485+ , row1 ~ '[col ::: ty]

486+ , GroupedBy tab col bys )

487+ => IsQualified tab col

488+ (Selection outer commons ('Grouped bys) schemas params from row1) where

489+ tab ! col = tab ! col `as` col

490+instance (HasUnique tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

491+ => IsLabel col

492+ (Selection outer commons 'Ungrouped schemas params from row1) where

493+ fromLabel = fromLabel @col `as` Alias

494+instance

495+ ( HasUnique tab (Join outer from) row0

496+ , Has col row0 ty

497+ , row1 ~ '[col ::: ty]

498+ , GroupedBy tab col bys )

499+ => IsLabel col

500+ (Selection outer commons ('Grouped bys) schemas params from row1) where

501+ fromLabel = fromLabel @col `as` Alias

502+

503+instance RenderSQL (Selection outer commons grp schemas params from row) where

504+ renderSQL = \case

505+ List list -> renderCommaSeparated (renderAliased renderSQL) list

506+ Star -> "*"

507+ DotStar tab -> renderSQL tab <> ".*"

508+ Also right left -> renderSQL left <> ", " <> renderSQL right

509+ Over winFns winDef ->

510+ let

511+ renderOver

512+ :: Aliased (WindowFunction outer commons grp schemas params from) field

513+ -> ByteString

514+ renderOver (winFn `As` col) = renderSQL winFn

515+ <+> "OVER" <+> parenthesized (renderSQL winDef)

516+ <+> "AS" <+> renderSQL col

517+ in

518+ renderCommaSeparated renderOver winFns

519+

520+instance IsString

521+ (Selection outer commons grp schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where

522+ fromString str = fromString str `as` Alias

523+

437524-- | the `TableExpression` in the `select` command constructs an intermediate

438525-- virtual table by possibly combining tables, views, eliminating rows,

439526-- grouping, etc. This table is finally passed on to processing by

440−-- the select list. The select list determines which columns of

527+-- the select list. The `Selection` determines which columns of

441528-- the intermediate table are actually output.

442529select

443− :: SListI columns

444− => NP (Aliased (Expression schema from grouping params)) (column ': columns)

445− -- ^ select list

446− -> TableExpression schema params from grouping

530+ :: (SListI row, row ~ (x ': xs))

531+ => Selection outer commons grp schemas params from row

532+ -- ^ selection

533+ -> TableExpression outer commons grp schemas params from

447534 -- ^ intermediate virtual table

448− -> Query schema params (column ': columns)

449−select list rels = UnsafeQuery $

535+ -> Query outer commons schemas params row

536+select selection tabexpr = UnsafeQuery $

450537 "SELECT"

451− <+> renderCommaSeparated (renderAliasedAs renderExpression) list

452− <+> renderTableExpression rels

538+ <+> renderSQL selection

539+ <+> renderSQL tabexpr

540+

541+-- | Like `select` but takes an `NP` list of `Expression`s instead

542+-- of a general `Selection`.

543+select_

544+ :: (SListI row, row ~ (x ': xs))

545+ => NP (Aliased (Expression outer commons grp schemas params from)) row

546+ -- ^ select list

547+ -> TableExpression outer commons grp schemas params from

548+ -- ^ intermediate virtual table

549+ -> Query outer commons schemas params row

550+select_ = select . List

453551

454552-- | After the select list has been processed, the result table can

455553-- be subject to the elimination of duplicate rows using `selectDistinct`.

456554selectDistinct

457− :: SListI columns

458− => NP (Aliased (Expression schema from 'Ungrouped params)) (column ': columns)

459− -- ^ select list

460− -> TableExpression schema params from 'Ungrouped

555+ :: (SListI columns, columns ~ (col ': cols))

556+ => Selection outer commons 'Ungrouped schemas params from columns

557+ -- ^ selection

558+ -> TableExpression outer commons 'Ungrouped schemas params from

461559 -- ^ intermediate virtual table

462− -> Query schema params (column ': columns)

463−selectDistinct list rels = UnsafeQuery $

560+ -> Query outer commons schemas params columns

561+selectDistinct selection tabexpr = UnsafeQuery $

464562 "SELECT DISTINCT"

465− <+> renderCommaSeparated (renderAliasedAs renderExpression) list

466− <+> renderTableExpression rels

467−

468−-- | The simplest kind of query is `selectStar` which emits all columns

469−-- that the table expression produces.

470−selectStar

471− :: HasUnique table from columns

472− => TableExpression schema params from 'Ungrouped

473− -- ^ intermediate virtual table

474− -> Query schema params columns

475−selectStar rels = UnsafeQuery $ "SELECT" <+> "*" <+> renderTableExpression rels

476−

477−-- | A `selectDistinctStar` emits all columns that the table expression

478−-- produces and eliminates duplicate rows.

479−selectDistinctStar

480− :: HasUnique table from columns

481− => TableExpression schema params from 'Ungrouped

482− -- ^ intermediate virtual table

483− -> Query schema params columns

484−selectDistinctStar rels = UnsafeQuery $

485− "SELECT DISTINCT" <+> "*" <+> renderTableExpression rels

486−

487−-- | When working with multiple tables, it can also be useful to ask

488−-- for all the columns of a particular table, using `selectDotStar`.

489−selectDotStar

490− :: Has table from columns

491− => Alias table

492− -- ^ particular virtual subtable

493− -> TableExpression schema params from 'Ungrouped

494− -- ^ intermediate virtual table

495− -> Query schema params columns

496−selectDotStar rel tab = UnsafeQuery $

497− "SELECT" <+> renderAlias rel <> ".*" <+> renderTableExpression tab

498−

499−-- | A `selectDistinctDotStar` asks for all the columns of a particular table,

500−-- and eliminates duplicate rows.

501−selectDistinctDotStar

502− :: Has table from columns

503− => Alias table

504− -- ^ particular virtual table

505− -> TableExpression schema params from 'Ungrouped

563+ <+> renderSQL selection

564+ <+> renderSQL tabexpr

565+

566+-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead

567+-- of a general `Selection`.

568+selectDistinct_

569+ :: (SListI columns, columns ~ (col ': cols))

570+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns

571+ -- ^ select list

572+ -> TableExpression outer commons 'Ungrouped schemas params from

506573 -- ^ intermediate virtual table

507− -> Query schema params columns

508−selectDistinctDotStar rel tab = UnsafeQuery $

509− "SELECT DISTINCT" <+> renderAlias rel <> ".*"

510− <+> renderTableExpression tab

574+ -> Query outer commons schemas params columns

575+selectDistinct_ = selectDistinct . List

511576

512577-- | `values` computes a row value or set of row values

513578-- specified by value expressions. It is most commonly used

@@ -515,16 +580,16 @@ selectDistinctDotStar rel tab = UnsafeQuery $

515580-- but it can be used on its own.

516581--

517582-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]

518−-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query '[] '[] Row

583+-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query outer commons schemas '[] Row

519584-- >>> printSQL query

520585-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")

521586values

522587 :: SListI cols

523− => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols

524− -> [NP (Aliased (Expression schema '[] 'Ungrouped params)) cols]

588+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

589+ -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]

525590 -- ^ When more than one row is specified, all the rows must

526591 -- must have the same number of elements

527− -> Query schema params cols

592+ -> Query outer commons schemas params cols

528593values rw rws = UnsafeQuery $ "SELECT * FROM"

529594 <+> parenthesized (

530595 "VALUES"

@@ -535,17 +600,17 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"

535600 <+> parenthesized (renderCommaSeparated renderAliasPart rw)

536601 where

537602 renderAliasPart, renderValuePart

538− :: Aliased (Expression schema '[] 'Ungrouped params) ty -> ByteString

539− renderAliasPart (_ `As` name) = renderAlias name

540− renderValuePart (value `As` _) = renderExpression value

603+ :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString

604+ renderAliasPart (_ `As` name) = renderSQL name

605+ renderValuePart (value `As` _) = renderSQL value

541606

542607-- | `values_` computes a row value or set of row values

543608-- specified by value expressions.

544609values_

545610 :: SListI cols

546− => NP (Aliased (Expression schema '[] 'Ungrouped params)) cols

611+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

547612 -- ^ one row of values

548− -> Query schema params cols

613+ -> Query outer commons schemas params cols

549614values_ rw = values rw []

550615

551616{-----------------------------------------

@@ -559,15 +624,17 @@ Table Expressions

559624-- to a table on disk, a so-called base table, but more complex expressions

560625-- can be used to modify or combine base tables in various ways.

561626data TableExpression

562− (schema :: SchemaType)

627+ (outer :: FromType)

628+ (commons :: FromType)

629+ (grp :: Grouping)

630+ (schemas :: SchemasType)

563631 (params :: [NullityType])

564632 (from :: FromType)

565− (grouping :: Grouping)

566633 = TableExpression

567− { fromClause :: FromClause schema params from

634+ { fromClause :: FromClause outer commons schemas params from

568635 -- ^ A table reference that can be a table name, or a derived table such

569636 -- as a subquery, a @JOIN@ construct, or complex combinations of these.

570− , whereClause :: [Condition schema from 'Ungrouped params]

637+ , whereClause :: [Condition outer commons 'Ungrouped schemas params from]

571638 -- ^ optional search coditions, combined with `.&&`. After the processing

572639 -- of the `fromClause` is done, each row of the derived virtual table

573640 -- is checked against the search condition. If the result of the

@@ -576,20 +643,20 @@ data TableExpression

576643 -- at least one column of the table generated in the `fromClause`;

577644 -- this is not required, but otherwise the WHERE clause will

578645 -- be fairly useless.

579− , groupByClause :: GroupByClause from grouping

646+ , groupByClause :: GroupByClause grp from

580647 -- ^ The `groupByClause` is used to group together those rows in a table

581648 -- that have the same values in all the columns listed. The order in which

582649 -- the columns are listed does not matter. The effect is to combine each

583650 -- set of rows having common values into one group row that represents all

584651 -- rows in the group. This is done to eliminate redundancy in the output

585652 -- and/or compute aggregates that apply to these groups.

586− , havingClause :: HavingClause schema from grouping params

653+ , havingClause :: HavingClause outer commons grp schemas params from

587654 -- ^ If a table has been grouped using `groupBy`, but only certain groups

588655 -- are of interest, the `havingClause` can be used, much like a

589656 -- `whereClause`, to eliminate groups from the result. Expressions in the

590657 -- `havingClause` can refer both to grouped expressions and to ungrouped

591658 -- expressions (which necessarily involve an aggregate function).

592− , orderByClause :: [SortExpression schema from grouping params]

659+ , orderByClause :: [SortExpression outer commons grp schemas params from]

593660 -- ^ The `orderByClause` is for optional sorting. When more than one

594661 -- `SortExpression` is specified, the later (right) values are used to sort

595662 -- rows that are equal according to the earlier (left) values.

@@ -599,68 +666,65 @@ data TableExpression

599666 -- will be returned (but possibly fewer, if the query itself yields

600667 -- fewer rows).

601668 , offsetClause :: [Word64]

602− -- ^ The `offsetClause` is combined with `+` to give an offset count

669+ -- ^ The `offsetClause` is combined with `Prelude.+` to give an offset count

603670 -- if nonempty. The offset count says to skip that many rows before

604671 -- beginning to return rows. The rows are skipped before the limit count

605672 -- is applied.

606− }

673+ } deriving (GHC.Generic)

607674

608675-- | Render a `TableExpression`

609−renderTableExpression

610− :: TableExpression schema params from grouping

611− -> ByteString

612−renderTableExpression

613− (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

614− [ "FROM ", renderFromClause frm'

615− , renderWheres whs'

616− , renderGroupByClause grps'

617− , renderHavingClause hvs'

618− , renderOrderByClause srts'

619− , renderLimits lims'

620− , renderOffsets offs'

621− ]

622− where

623− renderWheres = \case

624− [] -> ""

625− wh:[] -> " WHERE" <+> renderExpression wh

626− wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

627− renderOrderByClause = \case

628− [] -> ""

629− srts -> " ORDER BY"

630− <+> commaSeparated (renderSortExpression <$> srts)

631− renderLimits = \case

632− [] -> ""

633− lims -> " LIMIT" <+> fromString (show (minimum lims))

634− renderOffsets = \case

635− [] -> ""

636− offs -> " OFFSET" <+> fromString (show (sum offs))

676+instance RenderSQL (TableExpression outer commons grp schemas params from) where

677+ renderSQL

678+ (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

679+ [ "FROM ", renderSQL frm'

680+ , renderWheres whs'

681+ , renderSQL grps'

682+ , renderSQL hvs'

683+ , renderOrderByClause srts'

684+ , renderLimits lims'

685+ , renderOffsets offs' ]

686+ where

687+ renderWheres = \case

688+ [] -> ""

689+ wh:[] -> " WHERE" <+> renderSQL wh

690+ wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

691+ renderOrderByClause = \case

692+ [] -> ""

693+ srts -> " ORDER BY"

694+ <+> commaSeparated (renderSQL <$> srts)

695+ renderLimits = \case

696+ [] -> ""

697+ lims -> " LIMIT" <+> fromString (show (minimum lims))

698+ renderOffsets = \case

699+ [] -> ""

700+ offs -> " OFFSET" <+> fromString (show (sum offs))

637701

638702-- | A `from` generates a `TableExpression` from a table reference that can be

639703-- a table name, or a derived table such as a subquery, a JOIN construct,

640704-- or complex combinations of these. A `from` may be transformed by `where_`,

641−-- `group`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

705+-- `groupBy`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

642706-- to match the left-to-right sequencing of their placement in SQL.

643707from

644− :: FromClause schema params from -- ^ table reference

645− -> TableExpression schema params from 'Ungrouped

646−from rels = TableExpression rels [] NoGroups NoHaving [] [] []

708+ :: FromClause outer commons schemas params from -- ^ table reference

709+ -> TableExpression outer commons 'Ungrouped schemas params from

710+from tab = TableExpression tab [] NoGroups NoHaving [] [] []

647711

648712-- | A `where_` is an endomorphism of `TableExpression`s which adds a

649713-- search condition to the `whereClause`.

650714where_

651− :: Condition schema from 'Ungrouped params -- ^ filtering condition

652− -> TableExpression schema params from grouping

653− -> TableExpression schema params from grouping

715+ :: Condition outer commons 'Ungrouped schemas params from -- ^ filtering condition

716+ -> TableExpression outer commons grp schemas params from

717+ -> TableExpression outer commons grp schemas params from

654718where_ wh rels = rels {whereClause = wh : whereClause rels}

655719

656720-- | A `groupBy` is a transformation of `TableExpression`s which switches

657−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform

721+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform

658722-- a "grand total" aggregation query.

659723groupBy

660724 :: SListI bys

661725 => NP (By from) bys -- ^ grouped columns

662− -> TableExpression schema params from 'Ungrouped

663− -> TableExpression schema params from ('Grouped bys)

726+ -> TableExpression outer commons 'Ungrouped schemas params from

727+ -> TableExpression outer commons ('Grouped bys) schemas params from

664728groupBy bys rels = TableExpression

665729 { fromClause = fromClause rels

666730 , whereClause = whereClause rels

@@ -674,177 +738,31 @@ groupBy bys rels = TableExpression

674738-- | A `having` is an endomorphism of `TableExpression`s which adds a

675739-- search condition to the `havingClause`.

676740having

677− :: Condition schema from ('Grouped bys) params -- ^ having condition

678− -> TableExpression schema params from ('Grouped bys)

679− -> TableExpression schema params from ('Grouped bys)

741+ :: Condition outer commons ('Grouped bys) schemas params from -- ^ having condition

742+ -> TableExpression outer commons ('Grouped bys) schemas params from

743+ -> TableExpression outer commons ('Grouped bys) schemas params from

680744having hv rels = rels

681745 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }

682746

683−-- | An `orderBy` is an endomorphism of `TableExpression`s which appends an

684−-- ordering to the right of the `orderByClause`.

685−orderBy

686− :: [SortExpression schema from grouping params] -- ^ sort expressions

687− -> TableExpression schema params from grouping

688− -> TableExpression schema params from grouping

689−orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

747+instance OrderBy TableExpression where

748+ orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

690749

691750-- | A `limit` is an endomorphism of `TableExpression`s which adds to the

692751-- `limitClause`.

693752limit

694753 :: Word64 -- ^ limit parameter

695− -> TableExpression schema params from grouping

696− -> TableExpression schema params from grouping

754+ -> TableExpression outer commons grp schemas params from

755+ -> TableExpression outer commons grp schemas params from

697756limit lim rels = rels {limitClause = lim : limitClause rels}

698757

699758-- | An `offset` is an endomorphism of `TableExpression`s which adds to the

700759-- `offsetClause`.

701760offset

702761 :: Word64 -- ^ offset parameter

703− -> TableExpression schema params from grouping

704− -> TableExpression schema params from grouping

762+ -> TableExpression outer commons grp schemas params from

763+ -> TableExpression outer commons grp schemas params from

705764offset off rels = rels {offsetClause = off : offsetClause rels}

706765

707−{-----------------------------------------

708−JSON stuff

709−-----------------------------------------}

710−

711−unsafeSetOfFunction

712− :: ByteString

713− -> Expression schema '[] 'Ungrouped params ty

714− -> Query schema params row

715−unsafeSetOfFunction fun expr = UnsafeQuery $

716− "SELECT * FROM " <> fun <> "(" <> renderExpression expr <> ")"

717−

718−-- | Expands the outermost JSON object into a set of key/value pairs.

719−jsonEach

720− :: Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

721− -> Query schema params

722− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

723−jsonEach = unsafeSetOfFunction "json_each"

724−

725−-- | Expands the outermost binary JSON object into a set of key/value pairs.

726−jsonbEach

727− :: Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

728− -> Query schema params

729− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjsonb]

730−jsonbEach = unsafeSetOfFunction "jsonb_each"

731−

732−-- | Expands the outermost JSON object into a set of key/value pairs.

733−jsonEachAsText

734− :: Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

735− -> Query schema params

736− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

737−jsonEachAsText = unsafeSetOfFunction "json_each_text"

738−

739−-- | Expands the outermost binary JSON object into a set of key/value pairs.

740−jsonbEachAsText

741− :: Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

742− -> Query schema params

743− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

744−jsonbEachAsText = unsafeSetOfFunction "jsonb_each_text"

745−

746−-- | Returns set of keys in the outermost JSON object.

747−jsonObjectKeys

748− :: Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

749− -> Query schema params '["json_object_keys" ::: 'NotNull 'PGtext]

750−jsonObjectKeys = unsafeSetOfFunction "json_object_keys"

751−

752−-- | Returns set of keys in the outermost JSON object.

753−jsonbObjectKeys

754− :: Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

755− -> Query schema params '["jsonb_object_keys" ::: 'NotNull 'PGtext]

756−jsonbObjectKeys = unsafeSetOfFunction "jsonb_object_keys"

757−

758−unsafePopulateFunction

759− :: ByteString

760− -> TypeExpression schema (nullity ('PGcomposite row))

761− -> Expression schema '[] 'Ungrouped params ty

762− -> Query schema params row

763−unsafePopulateFunction fun ty expr = UnsafeQuery $

764− "SELECT * FROM " <> fun <> "("

765− <> "null::" <> renderTypeExpression ty <> ", "

766− <> renderExpression expr <> ")"

767−

768−-- | Expands the JSON expression to a row whose columns match the record

769−-- type defined by the given table.

770−jsonPopulateRecord

771− :: TypeExpression schema (nullity ('PGcomposite row)) -- ^ row type

772− -> Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

773− -> Query schema params row

774−jsonPopulateRecord = unsafePopulateFunction "json_populate_record"

775−

776−-- | Expands the binary JSON expression to a row whose columns match the record

777−-- type defined by the given table.

778−jsonbPopulateRecord

779− :: TypeExpression schema (nullity ('PGcomposite row)) -- ^ row type

780− -> Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

781− -> Query schema params row

782−jsonbPopulateRecord = unsafePopulateFunction "jsonb_populate_record"

783−

784−-- | Expands the outermost array of objects in the given JSON expression to a

785−-- set of rows whose columns match the record type defined by the given table.

786−jsonPopulateRecordSet

787− :: TypeExpression schema (nullity ('PGcomposite row)) -- ^ row type

788− -> Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json array

789− -> Query schema params row

790−jsonPopulateRecordSet = unsafePopulateFunction "json_populate_record_set"

791−

792−-- | Expands the outermost array of objects in the given binary JSON expression

793−-- to a set of rows whose columns match the record type defined by the given

794−-- table.

795−jsonbPopulateRecordSet

796− :: TypeExpression schema (nullity ('PGcomposite row)) -- ^ row type

797− -> Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb array

798− -> Query schema params row

799−jsonbPopulateRecordSet = unsafePopulateFunction "jsonb_populate_record_set"

800−

801−unsafeRecordFunction

802− :: (SListI record, json `In` PGJsonType)

803− => ByteString

804− -> Expression schema '[] 'Ungrouped params (nullity json)

805− -> NP (Aliased (TypeExpression schema)) record

806− -> Query schema params record

807−unsafeRecordFunction fun expr types = UnsafeQuery $

808− "SELECT * FROM " <> fun <> "("

809− <> renderExpression expr <> ")"

810− <+> "AS" <+> "x" <> parenthesized (renderCommaSeparated renderTy types)

811− where

812− renderTy :: Aliased (TypeExpression schema) ty -> ByteString

813− renderTy (ty `As` alias) =

814− renderAlias alias <+> renderTypeExpression ty

815−

816−-- | Builds an arbitrary record from a JSON object.

817−jsonToRecord

818− :: SListI record

819− => Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

820− -> NP (Aliased (TypeExpression schema)) record -- ^ record types

821− -> Query schema params record

822−jsonToRecord = unsafeRecordFunction "json_to_record"

823−

824−-- | Builds an arbitrary record from a binary JSON object.

825−jsonbToRecord

826− :: SListI record

827− => Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

828− -> NP (Aliased (TypeExpression schema)) record -- ^ record types

829− -> Query schema params record

830−jsonbToRecord = unsafeRecordFunction "jsonb_to_record"

831−

832−-- | Builds an arbitrary set of records from a JSON array of objects.

833−jsonToRecordSet

834− :: SListI record

835− => Expression schema '[] 'Ungrouped params (nullity 'PGjson) -- ^ json array

836− -> NP (Aliased (TypeExpression schema)) record -- ^ record types

837− -> Query schema params record

838−jsonToRecordSet = unsafeRecordFunction "json_to_record_set"

839−

840−-- | Builds an arbitrary set of records from a binary JSON array of objects.

841−jsonbToRecordSet

842− :: SListI record

843− => Expression schema '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb array

844− -> NP (Aliased (TypeExpression schema)) record -- ^ record types

845− -> Query schema params record

846−jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"

847−

848766{-----------------------------------------

849767FROM clauses

850768-----------------------------------------}

@@ -853,61 +771,76 @@ FROM clauses

853771A `FromClause` can be a table name, or a derived table such

854772as a subquery, a @JOIN@ construct, or complex combinations of these.

855773-}

856−newtype FromClause schema params from

774+newtype FromClause outer commons schemas params from

857775 = UnsafeFromClause { renderFromClause :: ByteString }

858776 deriving (GHC.Generic,Show,Eq,Ord,NFData)

777+instance RenderSQL (FromClause outer commons schemas params from) where

778+ renderSQL = renderFromClause

859779

860−-- | A real `table` is a table from the schema.

780+-- | A real `table` is a table from the database.

861781table

862− :: Has tab schema ('Table table)

863− => Aliased Alias (alias ::: tab)

864− -> FromClause schema params '[alias ::: TableToRow table]

782+ :: (Has sch schemas schema, Has tab schema ('Table table))

783+ => Aliased (QualifiedAlias sch) (alias ::: tab)

784+ -> FromClause outer commons schemas params '[alias ::: TableToRow table]

865785table (tab `As` alias) = UnsafeFromClause $

866− renderAlias tab <+> "AS" <+> renderAlias alias

786+ renderSQL tab <+> "AS" <+> renderSQL alias

867787

868788-- | `subquery` derives a table from a `Query`.

869789subquery

870− :: Aliased (Query schema params) rel

871− -> FromClause schema params '[rel]

872−subquery = UnsafeFromClause . renderAliasedAs (parenthesized . renderQuery)

790+ :: Aliased (Query outer commons schemas params) query

791+ -> FromClause outer commons schemas params '[query]

792+subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)

873793

874794-- | `view` derives a table from a `View`.

875795view

876− :: Has view schema ('View row)

877− => Aliased Alias (alias ::: view)

878− -> FromClause schema params '[alias ::: row]

796+ :: (Has sch schemas schema, Has vw schema ('View view))

797+ => Aliased (QualifiedAlias sch) (alias ::: vw)

798+ -> FromClause outer commons schemas params '[alias ::: view]

879799view (vw `As` alias) = UnsafeFromClause $

880− renderAlias vw <+> "AS" <+> renderAlias alias

800+ renderSQL vw <+> "AS" <+> renderSQL alias

881801

882−{- | @left & crossJoin right@. For every possible combination of rows from

883− @left@ and @right@ (i.e., a Cartesian product), the joined table will contain

884− a row consisting of all columns in @left@ followed by all columns in @right@.

885− If the tables have @n@ and @m@ rows respectively, the joined table will

886− have @n * m@ rows.

802+-- | `common` derives a table from a common table expression.

803+common

804+ :: Has cte commons common

805+ => Aliased Alias (alias ::: cte)

806+ -> FromClause outer commons schemas params '[alias ::: common]

807+common (cte `As` alias) = UnsafeFromClause $

808+ renderSQL cte <+> "AS" <+> renderSQL alias

809+

810+instance Additional (FromClause outer commons schemas params) where

811+ also right left = UnsafeFromClause $

812+ renderSQL left <> ", " <> renderSQL right

813+

814+{- |

815+@left & crossJoin right@. For every possible combination of rows from

816+@left@ and @right@ (i.e., a Cartesian product), the joined table will contain

817+a row consisting of all columns in @left@ followed by all columns in @right@.

818+If the tables have @n@ and @m@ rows respectively, the joined table will

819+have @n * m@ rows.

887820-}

888821crossJoin

889− :: FromClause schema params right

822+ :: FromClause outer commons schemas params right

890823 -- ^ right

891− -> FromClause schema params left

824+ -> FromClause outer commons schemas params left

892825 -- ^ left

893− -> FromClause schema params (Join left right)

826+ -> FromClause outer commons schemas params (Join left right)

894827crossJoin right left = UnsafeFromClause $

895− renderFromClause left <+> "CROSS JOIN" <+> renderFromClause right

828+ renderSQL left <+> "CROSS JOIN" <+> renderSQL right

896829

897830{- | @left & innerJoin right on@. The joined table is filtered by

898831the @on@ condition.

899832-}

900833innerJoin

901− :: FromClause schema params right

834+ :: FromClause outer commons schemas params right

902835 -- ^ right

903− -> Condition schema (Join left right) 'Ungrouped params

836+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

904837 -- ^ @on@ condition

905− -> FromClause schema params left

838+ -> FromClause outer commons schemas params left

906839 -- ^ left

907− -> FromClause schema params (Join left right)

840+ -> FromClause outer commons schemas params (Join left right)

908841innerJoin right on left = UnsafeFromClause $

909− renderFromClause left <+> "INNER JOIN" <+> renderFromClause right

910− <+> "ON" <+> renderExpression on

842+ renderSQL left <+> "INNER JOIN" <+> renderSQL right

843+ <+> "ON" <+> renderSQL on

911844

912845{- | @left & leftOuterJoin right on@. First, an inner join is performed.

913846 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -915,16 +848,16 @@ innerJoin right on left = UnsafeFromClause $

915848 Thus, the joined table always has at least one row for each row in @left@.

916849-}

917850leftOuterJoin

918− :: FromClause schema params right

851+ :: FromClause outer commons schemas params right

919852 -- ^ right

920− -> Condition schema (Join left right) 'Ungrouped params

853+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

921854 -- ^ @on@ condition

922− -> FromClause schema params left

855+ -> FromClause outer commons schemas params left

923856 -- ^ left

924− -> FromClause schema params (Join left (NullifyFrom right))

857+ -> FromClause outer commons schemas params (Join left (NullifyFrom right))

925858leftOuterJoin right on left = UnsafeFromClause $

926− renderFromClause left <+> "LEFT OUTER JOIN" <+> renderFromClause right

927− <+> "ON" <+> renderExpression on

859+ renderSQL left <+> "LEFT OUTER JOIN" <+> renderSQL right

860+ <+> "ON" <+> renderSQL on

928861

929862{- | @left & rightOuterJoin right on@. First, an inner join is performed.

930863 Then, for each row in @right@ that does not satisfy the @on@ condition with

@@ -933,16 +866,16 @@ leftOuterJoin right on left = UnsafeFromClause $

933866 have a row for each row in @right@.

934867-}

935868rightOuterJoin

936− :: FromClause schema params right

869+ :: FromClause outer commons schemas params right

937870 -- ^ right

938− -> Condition schema (Join left right) 'Ungrouped params

871+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

939872 -- ^ @on@ condition

940− -> FromClause schema params left

873+ -> FromClause outer commons schemas params left

941874 -- ^ left

942− -> FromClause schema params (Join (NullifyFrom left) right)

875+ -> FromClause outer commons schemas params (Join (NullifyFrom left) right)

943876rightOuterJoin right on left = UnsafeFromClause $

944− renderFromClause left <+> "RIGHT OUTER JOIN" <+> renderFromClause right

945− <+> "ON" <+> renderExpression on

877+ renderSQL left <+> "RIGHT OUTER JOIN" <+> renderSQL right

878+ <+> "ON" <+> renderSQL on

946879

947880{- | @left & fullOuterJoin right on@. First, an inner join is performed.

948881 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -952,23 +885,23 @@ rightOuterJoin right on left = UnsafeFromClause $

952885 is added.

953886-}

954887fullOuterJoin

955− :: FromClause schema params right

888+ :: FromClause outer commons schemas params right

956889 -- ^ right

957− -> Condition schema (Join left right) 'Ungrouped params

890+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

958891 -- ^ @on@ condition

959− -> FromClause schema params left

892+ -> FromClause outer commons schemas params left

960893 -- ^ left

961− -> FromClause schema params

894+ -> FromClause outer commons schemas params

962895 (Join (NullifyFrom left) (NullifyFrom right))

963896fullOuterJoin right on left = UnsafeFromClause $

964− renderFromClause left <+> "FULL OUTER JOIN" <+> renderFromClause right

965− <+> "ON" <+> renderExpression on

897+ renderSQL left <+> "FULL OUTER JOIN" <+> renderSQL right

898+ <+> "ON" <+> renderSQL on

966899

967900{-----------------------------------------

968901Grouping

969902-----------------------------------------}

970903

971−-- | `By`s are used in `group` to reference a list of columns which are then

904+-- | `By`s are used in `groupBy` to reference a list of columns which are then

972905-- used to group together those rows in a table that have the same values

973906-- in all the columns listed. @By \#col@ will reference an unambiguous

974907-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table

@@ -988,6 +921,10 @@ data By

988921deriving instance Show (By from by)

989922deriving instance Eq (By from by)

990923deriving instance Ord (By from by)

924+instance RenderSQL (By from by) where

925+ renderSQL = \case

926+ By1 column -> renderSQL column

927+ By2 rel column -> renderSQL rel <> "." <> renderSQL column

991928

992929instance (HasUnique rel rels cols, Has col cols ty, by ~ '(rel, col))

993930 => IsLabel col (By rels by) where fromLabel = By1 fromLabel

@@ -999,417 +936,112 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])

999936 => IsQualified rel col (NP (By rels) bys) where

1000937 rel ! col = By2 rel col :* Nil

1001938

1002−-- | Renders a `By`.

1003−renderBy :: By from by -> ByteString

1004−renderBy = \case

1005− By1 column -> renderAlias column

1006− By2 rel column -> renderAlias rel <> "." <> renderAlias column

1007−

1008939-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.

1009940-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.

1010941-- @NoGroups@ is distinguised from @Group Nil@ since no aggregation can be

1011942-- done on @NoGroups@ while all output `Expression`s must be aggregated

1012943-- in @Group Nil@. In general, all output `Expression`s in the

1013944-- complement of @bys@ must be aggregated in @Group bys@.

1014−data GroupByClause from grouping where

1015− NoGroups :: GroupByClause from 'Ungrouped

945+data GroupByClause grp from where

946+ NoGroups :: GroupByClause 'Ungrouped from

1016947 Group

1017948 :: SListI bys

1018949 => NP (By from) bys

1019− -> GroupByClause from ('Grouped bys)

950+ -> GroupByClause ('Grouped bys) from

1020951

1021952-- | Renders a `GroupByClause`.

1022−renderGroupByClause :: GroupByClause from grouping -> ByteString

1023−renderGroupByClause = \case

1024− NoGroups -> ""

1025− Group Nil -> ""

1026− Group bys -> " GROUP BY" <+> renderCommaSeparated renderBy bys

953+instance RenderSQL (GroupByClause grp from) where

954+ renderSQL = \case

955+ NoGroups -> ""

956+ Group Nil -> ""

957+ Group bys -> " GROUP BY" <+> renderCommaSeparated renderSQL bys

1027958

1028959-- | A `HavingClause` is used to eliminate groups that are not of interest.

1029960-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`

1030961-- `TableExpression` must use `Having` whose conditions are combined with

1031962-- `.&&`.

1032−data HavingClause schema from grouping params where

1033− NoHaving :: HavingClause schema from 'Ungrouped params

963+data HavingClause outer commons grp schemas params from where

964+ NoHaving :: HavingClause outer commons 'Ungrouped schemas params from

1034965 Having

1035− :: [Condition schema from ('Grouped bys) params]

1036− -> HavingClause schema from ('Grouped bys) params

1037−deriving instance Show (HavingClause schema from grouping params)

1038−deriving instance Eq (HavingClause schema from grouping params)

1039−deriving instance Ord (HavingClause schema from grouping params)

966+ :: [Condition outer commons ('Grouped bys) schemas params from]

967+ -> HavingClause outer commons ('Grouped bys) schemas params from

968+deriving instance Show (HavingClause outer commons grp schemas params from)

969+deriving instance Eq (HavingClause outer commons grp schemas params from)

970+deriving instance Ord (HavingClause outer commons grp schemas params from)

1040971

1041972-- | Render a `HavingClause`.

1042−renderHavingClause :: HavingClause schema from grouping params -> ByteString

1043−renderHavingClause = \case

1044− NoHaving -> ""

1045− Having [] -> ""

1046− Having conditions ->

1047− " HAVING" <+> commaSeparated (renderExpression <$> conditions)

1048−

1049−{-----------------------------------------

1050−Sorting

1051−-----------------------------------------}

1052−

1053−-- | `SortExpression`s are used by `sortBy` to optionally sort the results

1054−-- of a `Query`. `Asc` or `Desc` set the sort direction of a `NotNull` result

1055−-- column to ascending or descending. Ascending order puts smaller values

1056−-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,

1057−-- descending order is determined with the `.>` operator. `AscNullsFirst`,

1058−-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to

1059−-- determine whether nulls appear before or after non-null values in the sort

1060−-- ordering of a `Null` result column.

1061−data SortExpression schema from grouping params where

1062− Asc

1063− :: Expression schema from grouping params ('NotNull ty)

1064− -> SortExpression schema from grouping params

1065− Desc

1066− :: Expression schema from grouping params ('NotNull ty)

1067− -> SortExpression schema from grouping params

1068− AscNullsFirst

1069− :: Expression schema from grouping params ('Null ty)

1070− -> SortExpression schema from grouping params

1071− AscNullsLast

1072− :: Expression schema from grouping params ('Null ty)

1073− -> SortExpression schema from grouping params

1074− DescNullsFirst

1075− :: Expression schema from grouping params ('Null ty)

1076− -> SortExpression schema from grouping params

1077− DescNullsLast

1078− :: Expression schema from grouping params ('Null ty)

1079− -> SortExpression schema from grouping params

1080−deriving instance Show (SortExpression schema from grouping params)

1081−

1082−-- | Render a `SortExpression`.

1083−renderSortExpression :: SortExpression schema from grouping params -> ByteString

1084−renderSortExpression = \case

1085− Asc expression -> renderExpression expression <+> "ASC"

1086− Desc expression -> renderExpression expression <+> "DESC"

1087− AscNullsFirst expression -> renderExpression expression

1088− <+> "ASC NULLS FIRST"

1089− DescNullsFirst expression -> renderExpression expression

1090− <+> "DESC NULLS FIRST"

1091− AscNullsLast expression -> renderExpression expression <+> "ASC NULLS LAST"

1092− DescNullsLast expression -> renderExpression expression <+> "DESC NULLS LAST"

1093−

1094−unsafeSubqueryExpression

1095− :: ByteString

1096− -> Expression schema from grp params ty

1097− -> Query schema params '[alias ::: ty]

1098− -> Expression schema from grp params (nullity 'PGbool)

1099−unsafeSubqueryExpression op x q = UnsafeExpression $

1100− renderExpression x <+> op <+> parenthesized (renderQuery q)

1101−

1102−unsafeRowSubqueryExpression

1103− :: SListI row

1104− => ByteString

1105− -> NP (Aliased (Expression schema from grp params)) row

1106− -> Query schema params row

1107− -> Expression schema from grp params (nullity 'PGbool)

1108−unsafeRowSubqueryExpression op xs q = UnsafeExpression $

1109− renderExpression (row xs) <+> op <+> parenthesized (renderQuery q)

1110−

1111−-- | The right-hand side is a sub`Query`, which must return exactly one column.

1112−-- The left-hand expression is evaluated and compared to each row of the

1113−-- sub`Query` result. The result of `in_` is `true` if any equal subquery row is found.

1114−-- The result is `false` if no equal row is found

1115−-- (including the case where the subquery returns no rows).

1116−--

1117−-- >>> printSQL $ true `in_` values_ (true `as` #foo)

1118−-- TRUE IN (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1119−in_

1120− :: Expression schema from grp params ty -- ^ expression

1121− -> Query schema params '[alias ::: ty] -- ^ subquery

1122− -> Expression schema from grp params (nullity 'PGbool)

1123−in_ = unsafeSubqueryExpression "IN"

1124−

1125−{- | The left-hand side of this form of `rowIn` is a row constructor.

1126−The right-hand side is a sub`Query`,

1127−which must return exactly as many columns as

1128−there are expressions in the left-hand row.

1129−The left-hand expressions are evaluated and compared row-wise to each row

1130−of the subquery result. The result of `rowIn`

1131−is `true` if any equal subquery row is found.

1132−The result is `false` if no equal row is found

1133−(including the case where the subquery returns no rows).

1134−

1135−>>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1136−>>> printSQL $ myRow `rowIn` values_ myRow

1137−ROW(1, FALSE) IN (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1138−-}

1139−rowIn

1140− :: SListI row

1141− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1142− -> Query schema params row -- ^ subquery

1143− -> Expression schema from grp params (nullity 'PGbool)

1144−rowIn = unsafeRowSubqueryExpression "IN"

1145−

1146−-- | >>> printSQL $ true `eqAll` values_ (true `as` #foo)

1147−-- TRUE = ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1148−eqAll

1149− :: Expression schema from grp params ty -- ^ expression

1150− -> Query schema params '[alias ::: ty] -- ^ subquery

1151− -> Expression schema from grp params (nullity 'PGbool)

1152−eqAll = unsafeSubqueryExpression "= ALL"

1153−

1154−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1155−-- >>> printSQL $ myRow `rowEqAll` values_ myRow

1156−-- ROW(1, FALSE) = ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1157−rowEqAll

1158− :: SListI row

1159− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1160− -> Query schema params row -- ^ subquery

1161− -> Expression schema from grp params (nullity 'PGbool)

1162−rowEqAll = unsafeRowSubqueryExpression "= ALL"

1163−

1164−-- | >>> printSQL $ true `eqAny` values_ (true `as` #foo)

1165−-- TRUE = ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1166−eqAny

1167− :: Expression schema from grp params ty -- ^ expression

1168− -> Query schema params '[alias ::: ty] -- ^ subquery

1169− -> Expression schema from grp params (nullity 'PGbool)

1170−eqAny = unsafeSubqueryExpression "= ANY"

1171−

1172−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1173−-- >>> printSQL $ myRow `rowEqAny` values_ myRow

1174−-- ROW(1, FALSE) = ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1175−rowEqAny

1176− :: SListI row

1177− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1178− -> Query schema params row -- ^ subquery

1179− -> Expression schema from grp params (nullity 'PGbool)

1180−rowEqAny = unsafeRowSubqueryExpression "= ANY"

1181−

1182−-- | >>> printSQL $ true `neqAll` values_ (true `as` #foo)

1183−-- TRUE <> ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1184−neqAll

1185− :: Expression schema from grp params ty -- ^ expression

1186− -> Query schema params '[alias ::: ty] -- ^ subquery

1187− -> Expression schema from grp params (nullity 'PGbool)

1188−neqAll = unsafeSubqueryExpression "<> ALL"

1189−

1190−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1191−-- >>> printSQL $ myRow `rowNeqAll` values_ myRow

1192−-- ROW(1, FALSE) <> ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1193−rowNeqAll

1194− :: SListI row

1195− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1196− -> Query schema params row -- ^ subquery

1197− -> Expression schema from grp params (nullity 'PGbool)

1198−rowNeqAll = unsafeRowSubqueryExpression "<> ALL"

1199−

1200−-- | >>> printSQL $ true `neqAny` values_ (true `as` #foo)

1201−-- TRUE <> ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1202−neqAny

1203− :: Expression schema from grp params ty -- ^ expression

1204− -> Query schema params '[alias ::: ty] -- ^ subquery

1205− -> Expression schema from grp params (nullity 'PGbool)

1206−neqAny = unsafeSubqueryExpression "<> ANY"

1207−

1208−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1209−-- >>> printSQL $ myRow `rowNeqAny` values_ myRow

1210−-- ROW(1, FALSE) <> ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1211−rowNeqAny

1212− :: SListI row

1213− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1214− -> Query schema params row -- ^ subquery

1215− -> Expression schema from grp params (nullity 'PGbool)

1216−rowNeqAny = unsafeRowSubqueryExpression "<> ANY"

1217−

1218−-- | >>> printSQL $ true `allLt` values_ (true `as` #foo)

1219−-- TRUE ALL < (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1220−allLt

1221− :: Expression schema from grp params ty -- ^ expression

1222− -> Query schema params '[alias ::: ty] -- ^ subquery

1223− -> Expression schema from grp params (nullity 'PGbool)

1224−allLt = unsafeSubqueryExpression "ALL <"

1225−

1226−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1227−-- >>> printSQL $ myRow `rowLtAll` values_ myRow

1228−-- ROW(1, FALSE) ALL < (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1229−rowLtAll

1230− :: SListI row

1231− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1232− -> Query schema params row -- ^ subquery

1233− -> Expression schema from grp params (nullity 'PGbool)

1234−rowLtAll = unsafeRowSubqueryExpression "ALL <"

1235−

1236−-- | >>> printSQL $ true `ltAny` values_ (true `as` #foo)

1237−-- TRUE ANY < (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1238−ltAny

1239− :: Expression schema from grp params ty -- ^ expression

1240− -> Query schema params '[alias ::: ty] -- ^ subquery

1241− -> Expression schema from grp params (nullity 'PGbool)

1242−ltAny = unsafeSubqueryExpression "ANY <"

1243−

1244−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1245−-- >>> printSQL $ myRow `rowLtAll` values_ myRow

1246−-- ROW(1, FALSE) ALL < (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1247−rowLtAny

1248− :: SListI row

1249− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1250− -> Query schema params row -- ^ subquery

1251− -> Expression schema from grp params (nullity 'PGbool)

1252−rowLtAny = unsafeRowSubqueryExpression "ANY <"

1253−

1254−-- | >>> printSQL $ true `lteAll` values_ (true `as` #foo)

1255−-- TRUE <= ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1256−lteAll

1257− :: Expression schema from grp params ty -- ^ expression

1258− -> Query schema params '[alias ::: ty] -- ^ subquery

1259− -> Expression schema from grp params (nullity 'PGbool)

1260−lteAll = unsafeSubqueryExpression "<= ALL"

1261−

1262−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1263−-- >>> printSQL $ myRow `rowLteAll` values_ myRow

1264−-- ROW(1, FALSE) <= ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1265−rowLteAll

1266− :: SListI row

1267− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1268− -> Query schema params row -- ^ subquery

1269− -> Expression schema from grp params (nullity 'PGbool)

1270−rowLteAll = unsafeRowSubqueryExpression "<= ALL"

1271−

1272−-- | >>> printSQL $ true `lteAny` values_ (true `as` #foo)

1273−-- TRUE <= ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1274−lteAny

1275− :: Expression schema from grp params ty -- ^ expression

1276− -> Query schema params '[alias ::: ty] -- ^ subquery

1277− -> Expression schema from grp params (nullity 'PGbool)

1278−lteAny = unsafeSubqueryExpression "<= ANY"

1279−

1280−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1281−-- >>> printSQL $ myRow `rowLteAny` values_ myRow

1282−-- ROW(1, FALSE) <= ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1283−rowLteAny

1284− :: SListI row

1285− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1286− -> Query schema params row -- ^ subquery

1287− -> Expression schema from grp params (nullity 'PGbool)

1288−rowLteAny = unsafeRowSubqueryExpression "<= ANY"

1289−

1290−-- | >>> printSQL $ true `gtAll` values_ (true `as` #foo)

1291−-- TRUE > ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1292−gtAll

1293− :: Expression schema from grp params ty -- ^ expression

1294− -> Query schema params '[alias ::: ty] -- ^ subquery

1295− -> Expression schema from grp params (nullity 'PGbool)

1296−gtAll = unsafeSubqueryExpression "> ALL"

1297−

1298−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1299−-- >>> printSQL $ myRow `rowGtAll` values_ myRow

1300−-- ROW(1, FALSE) > ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1301−rowGtAll

1302− :: SListI row

1303− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1304− -> Query schema params row -- ^ subquery

1305− -> Expression schema from grp params (nullity 'PGbool)

1306−rowGtAll = unsafeRowSubqueryExpression "> ALL"

1307−

1308−-- | >>> printSQL $ true `gtAny` values_ (true `as` #foo)

1309−-- TRUE > ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1310−gtAny

1311− :: Expression schema from grp params ty -- ^ expression

1312− -> Query schema params '[alias ::: ty] -- ^ subquery

1313− -> Expression schema from grp params (nullity 'PGbool)

1314−gtAny = unsafeSubqueryExpression "> ANY"

1315−

1316−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1317−-- >>> printSQL $ myRow `rowGtAny` values_ myRow

1318−-- ROW(1, FALSE) > ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1319−rowGtAny

1320− :: SListI row

1321− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1322− -> Query schema params row -- ^ subquery

1323− -> Expression schema from grp params (nullity 'PGbool)

1324−rowGtAny = unsafeRowSubqueryExpression "> ANY"

1325−

1326−-- | >>> printSQL $ true `gteAll` values_ (true `as` #foo)

1327−-- TRUE >= ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1328−gteAll

1329− :: Expression schema from grp params ty -- ^ expression

1330− -> Query schema params '[alias ::: ty] -- ^ subquery

1331− -> Expression schema from grp params (nullity 'PGbool)

1332−gteAll = unsafeSubqueryExpression ">= ALL"

1333−

1334−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1335−-- >>> printSQL $ myRow `rowGteAll` values_ myRow

1336−-- ROW(1, FALSE) >= ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1337−rowGteAll

1338− :: SListI row

1339− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1340− -> Query schema params row -- ^ subquery

1341− -> Expression schema from grp params (nullity 'PGbool)

1342−rowGteAll = unsafeRowSubqueryExpression ">= ALL"

1343−

1344−-- | >>> printSQL $ true `gteAny` values_ (true `as` #foo)

1345−-- TRUE >= ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1346−gteAny

1347− :: Expression schema from grp params ty -- ^ expression

1348− -> Query schema params '[alias ::: ty] -- ^ subquery

1349− -> Expression schema from grp params (nullity 'PGbool)

1350−gteAny = unsafeSubqueryExpression ">= ANY"

1351−

1352−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression '[] '[] 'Ungrouped '[])) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1353−-- >>> printSQL $ myRow `rowGteAny` values_ myRow

1354−-- ROW(1, FALSE) >= ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1355−rowGteAny

1356− :: SListI row

1357− => NP (Aliased (Expression schema from grp params)) row -- ^ row constructor

1358− -> Query schema params row -- ^ subquery

1359− -> Expression schema from grp params (nullity 'PGbool)

1360−rowGteAny = unsafeRowSubqueryExpression ">= ANY"

973+instance RenderSQL (HavingClause outer commons grp schemas params from) where

974+ renderSQL = \case

975+ NoHaving -> ""

976+ Having [] -> ""

977+ Having conditions ->

978+ " HAVING" <+> commaSeparated (renderSQL <$> conditions)

1361979

1362980-- | A `CommonTableExpression` is an auxiliary statement in a `with` clause.

1363981data CommonTableExpression statement

982+ (schemas :: SchemasType)

1364983 (params :: [NullityType])

1365− (schema0 :: SchemaType)

1366− (schema1 :: SchemaType) where

984+ (commons0 :: FromType)

985+ (commons1 :: FromType) where

1367986 CommonTableExpression

1368− :: Aliased (statement schema params) (alias ::: cte)

1369− -> CommonTableExpression

1370− statement params schema (alias ::: 'View cte ': schema)

1371−instance (KnownSymbol alias, schema1 ~ (alias ::: 'View cte ': schema))

1372− => Aliasable alias

1373− (statement schema params cte)

1374− (CommonTableExpression statement params schema schema1) where

1375− statement `as` alias = CommonTableExpression (statement `as` alias)

1376−instance (KnownSymbol alias, schema1 ~ (alias ::: 'View cte ': schema))

1377− => Aliasable alias (statement schema params cte)

1378− (AlignedList (CommonTableExpression statement params) schema schema1) where

1379− statement `as` alias = single (statement `as` alias)

1380−

1381−-- | render a `CommonTableExpression`.

1382−renderCommonTableExpression

1383− :: (forall sch ps row. statement ps sch row -> ByteString) -- ^ render statement

1384− -> CommonTableExpression statement params schema0 schema1 -> ByteString

1385−renderCommonTableExpression renderStatement

1386− (CommonTableExpression (statement `As` alias)) =

1387− renderAlias alias <+> "AS" <+> parenthesized (renderStatement statement)

1388−

1389−-- | render a non-empty `AlignedList` of `CommonTableExpression`s.

1390−renderCommonTableExpressions

1391− :: (forall sch ps row. statement ps sch row -> ByteString) -- ^ render statement

1392− -> CommonTableExpression statement params schema0 schema1

1393− -> AlignedList (CommonTableExpression statement params) schema1 schema2

1394− -> ByteString

1395−renderCommonTableExpressions renderStatement cte ctes =

1396− renderCommonTableExpression renderStatement cte <> case ctes of

1397− Done -> ""

1398− cte' :>> ctes' -> "," <+>

1399− renderCommonTableExpressions renderStatement cte' ctes'

987+ :: Aliased (statement commons schemas params) (cte ::: common)

988+ -> CommonTableExpression statement schemas params commons (cte ::: common ': commons)

989+instance

990+ ( KnownSymbol cte

991+ , commons1 ~ (cte ::: common ': commons)

992+ ) => Aliasable cte

993+ (statement commons schemas params common)

994+ (CommonTableExpression statement schemas params commons commons1) where

995+ statement `as` cte = CommonTableExpression (statement `as` cte)

996+instance

997+ ( KnownSymbol cte

998+ , commons1 ~ (cte ::: common ': commons)

999+ ) => Aliasable cte

1000+ (statement commons schemas params common)

1001+ (AlignedList (CommonTableExpression statement schemas params) commons commons1) where

1002+ statement `as` cte = single (statement `as` cte)

1003+

1004+instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL

1005+ (CommonTableExpression statement schemas params commons0 commons1) where

1006+ renderSQL (CommonTableExpression (statement `As` cte)) =

1007+ renderSQL cte <+> "AS" <+> parenthesized (renderSQL statement)

14001008

14011009-- | `with` provides a way to write auxiliary statements for use in a larger query.

14021010-- These statements, referred to as `CommonTableExpression`s, can be thought of as

14031011-- defining temporary tables that exist just for one query.

14041012class With statement where

14051013 with

1406− :: AlignedList (CommonTableExpression statement params) schema0 schema1

1014+ :: AlignedList (CommonTableExpression statement schemas params) commons0 commons1

14071015 -- ^ common table expressions

1408− -> statement schema1 params row

1016+ -> statement commons1 schemas params row

14091017 -- ^ larger query

1410− -> statement schema0 params row

1411−instance With Query where

1018+ -> statement commons0 schemas params row

1019+instance With (Query outer) where

14121020 with Done query = query

1413− with (cte :>> ctes) query = UnsafeQuery $

1414− "WITH" <+> renderCommonTableExpressions renderQuery cte ctes

1415− <+> renderQuery query

1021+ with ctes query = UnsafeQuery $

1022+ "WITH" <+> renderSQL ctes <+> renderSQL query

1023+

1024+{- |

1025+>>> import Data.Monoid (Sum (..))

1026+>>> import Data.Int (Int32)

1027+>>> :{

1028+ let

1029+ query :: Query_ schema () (Sum Int32)

1030+ query = withRecursive

1031+ ( values_ (1 `as` #n)

1032+ `unionAll`

1033+ select_ ((#n + 1) `as` #n)

1034+ (from (common #t) & where_ (#n .< 100)) `as` #t )

1035+ ( select_ (fromNull 0 (sum_ (All #n)) `as` #getSum) (from (common #t) & groupBy Nil))

1036+ in printSQL query

1037+:}

1038+WITH RECURSIVE "t" AS ((SELECT * FROM (VALUES (1)) 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"

1039+-}

1040+withRecursive

1041+ :: Aliased (Query outer (recursive ': commons) schemas params) recursive

1042+ -> Query outer (recursive ': commons) schemas params row

1043+ -> Query outer commons schemas params row

1044+withRecursive (recursive `As` cte) query = UnsafeQuery $

1045+ "WITH RECURSIVE" <+> renderSQL cte

1046+ <+> "AS" <+> parenthesized (renderSQL recursive)

1047+ <+> renderSQL query

squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+47−14

@@ -10,7 +10,9 @@ Rendering helper functions.

1010

1111{-# LANGUAGE

1212 AllowAmbiguousTypes

13+ , ConstraintKinds

1314 , FlexibleContexts

15+ , LambdaCase

1416 , MagicHash

1517 , OverloadedStrings

1618 , PolyKinds

@@ -21,30 +23,34 @@ Rendering helper functions.

2123

2224module Squeal.PostgreSQL.Render

2325 ( -- * Render

24− parenthesized

26+ RenderSQL (..)

27+ , printSQL

28+ , escape

29+ , parenthesized

30+ , bracketed

2531 , (<+>)

2632 , commaSeparated

2733 , doubleQuoted

2834 , singleQuotedText

2935 , singleQuotedUtf8

3036 , renderCommaSeparated

37+ , renderCommaSeparatedConstraint

3138 , renderCommaSeparatedMaybe

3239 , renderNat

3340 , renderSymbol

34− , RenderSQL (..)

35− , printSQL

3641 ) where

3742

38−import Control.Monad.Base

43+import Control.Monad.IO.Class (MonadIO (..))

3944import Data.ByteString (ByteString)

40−import Data.Maybe

45+import Data.Maybe (catMaybes)

4146import Data.Monoid ((<>))

4247import Data.Text (Text)

4348import Generics.SOP

4449import GHC.Exts

45−import GHC.TypeLits

46−import qualified Data.Text as T

47−import qualified Data.Text.Encoding as T

50+import GHC.TypeLits hiding (Text)

51+

52+import qualified Data.Text as Text

53+import qualified Data.Text.Encoding as Text

4854import qualified Data.ByteString as ByteString

4955import qualified Data.ByteString.Char8 as Char8

5056

@@ -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 <+>

@@ -67,11 +77,12 @@ doubleQuoted str = "\"" <> str <> "\""

6777

6878-- | Add single quotes around a `Text` and escape single quotes within it.

6979singleQuotedText :: Text -> ByteString

70−singleQuotedText str = "'" <> T.encodeUtf8 (T.replace "'" "''" str) <> "'"

80+singleQuotedText str =

81+ "'" <> Text.encodeUtf8 (Text.replace "'" "''" str) <> "'"

7182

7283-- | Add single quotes around a `ByteString` and escape single quotes within it.

7384singleQuotedUtf8 :: ByteString -> ByteString

74−singleQuotedUtf8 = singleQuotedText . T.decodeUtf8

85+singleQuotedUtf8 = singleQuotedText . Text.decodeUtf8

7586

7687-- | Comma separate the renderings of a heterogeneous list.

7788renderCommaSeparated

@@ -83,6 +94,16 @@ renderCommaSeparated render

8394 . hcollapse

8495 . hmap (K . render)

8596

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+

86107-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping

87108-- `Nothing`s.

88109renderCommaSeparatedMaybe

@@ -104,9 +125,21 @@ renderSymbol :: forall s. KnownSymbol s => ByteString

104125renderSymbol = fromString (symbolVal' (proxy# :: Proxy# s))

105126

106127-- | A class for rendering SQL

107−class RenderSQL sql where

108− renderSQL :: sql -> ByteString

128+class 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+67−498

@@ -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

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

@@ -22,6 +21,7 @@ it defines an embedding of Haskell types into Postgres types.

2221 , GADTs

2322 , LambdaCase

2423 , OverloadedStrings

24+ , QuantifiedConstraints

2525 , RankNTypes

2626 , ScopedTypeVariables

2727 , StandaloneDeriving

@@ -39,73 +39,37 @@ module Squeal.PostgreSQL.Schema

3939 , NullityType (..)

4040 , RowType

4141 , FromType

42− -- * Haskell to Postgres Types

43− , PG

44− , NullPG

45− , TuplePG

46− , RowPG

47− , Json (..)

48− , Jsonb (..)

49− , Composite (..)

50− , Enumerated (..)

5142 -- * Schema Types

5243 , ColumnType

5344 , ColumnsType

5445 , TableType

5546 , SchemumType (..)

5647 , SchemaType

48+ , SchemasType

49+ , Public

5750 -- * Constraints

5851 , (:=>)

5952 , ColumnConstraint (..)

6053 , TableConstraint (..)

6154 , TableConstraints

6255 , Uniquely

63− -- * Aliases

64− , (:::)

65− , Alias (Alias)

66− , renderAlias

67− , renderAliases

68− , Aliased (As)

69− , Aliasable (as)

70− , renderAliasedAs

71− , Has

72− , HasUnique

73− , HasAll

74− , IsLabel (..)

75− , IsQualified (..)

76− , renderAliasString

7756 -- * Enumerated Labels

7857 , IsPGlabel (..)

7958 , PGlabel (..)

80− , renderLabel

81− , renderLabels

82− , LabelsPG

83− -- * Grouping

84− , Grouping (..)

85− , GroupedBy

86− -- * Aligned lists

87− , AlignedList (..)

88− , single

8959 -- * Data Definitions

9060 , Create

9161 , Drop

9262 , Alter

9363 , Rename

64+ , ConstraintInvolves

9465 , DropIfConstraintsInvolve

95− -- * Lists

96− , Join

97− , Elem

98− , In

99− , Length

66+ , IsNotElem

67+ , AllUnique

10068 -- * Type Classifications

101− , HasOid (..)

10269 , PGNum

10370 , PGIntegral

10471 , PGFloating

10572 , PGTypeOf

106− , PGArrayOf

107− , PGArray

108− , PGTextArray

10973 , PGJsonType

11074 , PGJsonKey

11175 , SamePGType

@@ -117,41 +81,27 @@ module Squeal.PostgreSQL.Schema

11781 , NullifyFrom

11882 -- * Table Conversions

11983 , TableToColumns

84+ , ColumnsToRow

12085 , TableToRow

12186 ) where

12287

12388import Control.Category

124−import Control.DeepSeq

125−import Data.Aeson (Value)

126−import Data.ByteString (ByteString)

127−import Data.Int (Int16, Int32, Int64)

12889import Data.Kind

12990import Data.Monoid hiding (All)

130−import Data.Scientific (Scientific)

131−import Data.String

132−import Data.Text (Text)

133−import Data.Time

134−import Data.Word (Word16, Word32, Word64)

13591import Data.Type.Bool

136−import Data.UUID.Types (UUID)

137−import Data.Vector (Vector)

13892import Generics.SOP

139−import Generics.SOP.Record

140−import GHC.OverloadedLabels

14193import GHC.TypeLits

142−import Network.IP.Addr

14394import Prelude hiding (id, (.))

14495

145−import qualified Data.ByteString.Lazy as Lazy

146−import qualified Data.Text.Lazy as Lazy

147−import qualified GHC.Generics as GHC

148−import qualified Generics.SOP.Type.Metadata as Type

149−

96+import Squeal.PostgreSQL.Alias

97+import Squeal.PostgreSQL.List

15098import Squeal.PostgreSQL.Render

15199

100+-- $setup

101+-- >>> import Squeal.PostgreSQL

102+

152103-- | `PGType` is the promoted datakind of PostgreSQL types.

153104--

154−-- >>> import Squeal.PostgreSQL.Schema

155105-- >>> :kind 'PGbool

156106-- 'PGbool :: PGType

157107data PGType

@@ -162,6 +112,7 @@ data PGType

162112 | PGnumeric -- ^ arbitrary precision numeric type

163113 | PGfloat4 -- ^ single precision floating-point number (4 bytes)

164114 | PGfloat8 -- ^ double precision floating-point number (8 bytes)

115+ | PGmoney -- ^ currency amount

165116 | PGchar Nat -- ^ fixed-length character string

166117 | PGvarchar Nat -- ^ variable-length character string

167118 | PGtext -- ^ variable-length character string

@@ -177,39 +128,13 @@ data PGType

177128 | PGjson -- ^ textual JSON data

178129 | PGjsonb -- ^ binary JSON data, decomposed

179130 | PGvararray NullityType -- ^ variable length array

180− | PGfixarray Nat NullityType -- ^ fixed length array

131+ | PGfixarray [Nat] NullityType -- ^ fixed length array

181132 | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.

182133 | 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.

134+ | 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.

135+ | PGtsquery -- ^ A tsquery value stores lexemes that are to be searched for

183136 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types

184137

185−-- | The object identifier of a `PGType`.

186−--

187−-- >>> :set -XTypeApplications

188−-- >>> oid @'PGbool

189−-- 16

190−class HasOid (ty :: PGType) where oid :: Word32

191−instance HasOid 'PGbool where oid = 16

192−instance HasOid 'PGint2 where oid = 21

193−instance HasOid 'PGint4 where oid = 23

194−instance HasOid 'PGint8 where oid = 20

195−instance HasOid 'PGnumeric where oid = 1700

196−instance HasOid 'PGfloat4 where oid = 700

197−instance HasOid 'PGfloat8 where oid = 701

198−instance HasOid ('PGchar n) where oid = 18

199−instance HasOid ('PGvarchar n) where oid = 1043

200−instance HasOid 'PGtext where oid = 25

201−instance HasOid 'PGbytea where oid = 17

202−instance HasOid 'PGtimestamp where oid = 1114

203−instance HasOid 'PGtimestamptz where oid = 1184

204−instance HasOid 'PGdate where oid = 1082

205−instance HasOid 'PGtime where oid = 1083

206−instance HasOid 'PGtimetz where oid = 1266

207−instance HasOid 'PGinterval where oid = 1186

208−instance HasOid 'PGuuid where oid = 2950

209−instance HasOid 'PGinet where oid = 869

210−instance HasOid 'PGjson where oid = 114

211−instance HasOid 'PGjsonb where oid = 3802

212−

213138-- | `NullityType` encodes the potential presence or definite absence of a

214139-- @NULL@ allowing operations which are sensitive to such to be well typed.

215140--

@@ -228,11 +153,6 @@ data NullityType

228153type (:=>) constraint ty = '(constraint,ty)

229154infixr 7 :=>

230155

231−-- | The alias operator `:::` is like a promoted version of `As`,

232−-- a type level pair between an alias and some type.

233−type (:::) (alias :: Symbol) ty = '(alias,ty)

234−infixr 6 :::

235−

236156-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.

237157-- A column can be assigned a default value.

238158-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also

@@ -274,7 +194,13 @@ data TableConstraint

274194 | PrimaryKey [Symbol]

275195 | ForeignKey [Symbol] Symbol [Symbol]

276196

277−-- | A `TableConstraints` is a row of `TableConstraint`s.

197+{- | A `TableConstraints` is a row of `TableConstraint`s.

198+

199+>>> :{

200+type family UsersConstraints :: TableConstraints where

201+ UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]

202+:}

203+-}

278204type TableConstraints = [(Symbol,TableConstraint)]

279205

280206-- | A `ForeignKey` must reference columns that either are

@@ -300,7 +226,7 @@ type family Uniquely

300226type TableType = (TableConstraints,ColumnsType)

301227

302228{- | A `RowType` is a row of `NullityType`. They correspond to Haskell

303−record types by means of `RowPG` and are used in many places.

229+record types by means of `Squeal.PostgreSQL.Binary.RowPG` and are used in many places.

304230

305231>>> :{

306232type family PersonRow :: RowType where

@@ -333,153 +259,6 @@ type family TableToColumns (table :: TableType) :: ColumnsType where

333259type family TableToRow (table :: TableType) :: RowType where

334260 TableToRow tab = ColumnsToRow (TableToColumns tab)

335261

336−-- | `Grouping` is an auxiliary namespace, created by

337−-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used

338−-- for typesafe aggregation

339−data Grouping

340− = Ungrouped -- ^ no aggregation permitted

341− | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped

342−

343−{- | A `GroupedBy` constraint indicates that a table qualified column is

344−a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,

345−may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.

346−-}

347−class (KnownSymbol table, KnownSymbol column)

348− => GroupedBy table column bys where

349−instance {-# OVERLAPPING #-} (KnownSymbol table, KnownSymbol column)

350− => GroupedBy table column ('(table,column) ': bys)

351−instance {-# OVERLAPPABLE #-}

352− ( KnownSymbol table

353− , KnownSymbol column

354− , GroupedBy table column bys

355− ) => GroupedBy table column (tabcol ': bys)

356−

357−-- | `Alias`es are proxies for a type level string or `Symbol`

358−-- and have an `IsLabel` instance so that with @-XOverloadedLabels@

359−--

360−-- >>> :set -XOverloadedLabels

361−-- >>> #foobar :: Alias "foobar"

362−-- Alias

363−data Alias (alias :: Symbol) = Alias

364− deriving (Eq,GHC.Generic,Ord,Show,NFData)

365−instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where

366− fromLabel = Alias

367−instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where

368− fromLabel = fromLabel :* Nil

369−instance KnownSymbol alias => RenderSQL (Alias alias) where renderSQL = renderAlias

370−

371−-- | >>> renderAlias #jimbob

372−-- "\"jimbob\""

373−renderAlias :: KnownSymbol alias => Alias alias -> ByteString

374−renderAlias = doubleQuoted . fromString . symbolVal

375−

376−-- | >>> renderAliasString #ohmahgerd

377−-- "'ohmahgerd'"

378−renderAliasString :: KnownSymbol alias => Alias alias -> ByteString

379−renderAliasString = singleQuotedText . fromString . symbolVal

380−

381−-- | >>> import Generics.SOP (NP(..))

382−-- >>> renderAliases (#jimbob :* #kandi)

383−-- ["\"jimbob\"","\"kandi\""]

384−renderAliases

385− :: All KnownSymbol aliases => NP Alias aliases -> [ByteString]

386−renderAliases = hcollapse

387− . hcmap (Proxy @KnownSymbol) (K . renderAlias)

388−

389−-- | The `As` operator is used to name an expression. `As` is like a demoted

390−-- version of `:::`.

391−--

392−-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)

393−-- As (Just "hello") Alias

394−data Aliased expression aliased where

395− As

396− :: KnownSymbol alias

397− => expression ty

398− -> Alias alias

399− -> Aliased expression (alias ::: ty)

400−deriving instance Show (expression ty)

401− => Show (Aliased expression (alias ::: ty))

402−deriving instance Eq (expression ty)

403− => Eq (Aliased expression (alias ::: ty))

404−deriving instance Ord (expression ty)

405− => Ord (Aliased expression (alias ::: ty))

406−instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)

407− => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where

408− fromLabel = fromLabel @alias2 `As` fromLabel @alias1

409−

410−-- | The `Aliasable` class provides a way to scrap your `Nil`s

411−-- in an `NP` list of `Aliased` expressions.

412−class KnownSymbol alias => Aliasable alias expression aliased

413− | aliased -> expression

414− , aliased -> alias

415− where as :: expression -> Alias alias -> aliased

416−instance (KnownSymbol alias, alias ~ alias1) => Aliasable alias

417− (expression ty)

418− (Aliased expression (alias1 ::: ty))

419− where

420− as = As

421−instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias

422− (expression ty)

423− (NP (Aliased expression) tys)

424− where

425− expression `as` alias = expression `As` alias :* Nil

426−

427−-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")

428−-- >>> renderAliasedAs renderMaybe (Just (3::Int) `As` #an_int)

429−-- "Just AS \"an_int\""

430−renderAliasedAs

431− :: (forall ty. expression ty -> ByteString)

432− -> Aliased expression aliased

433− -> ByteString

434−renderAliasedAs render (expression `As` alias) =

435− render expression <> " AS " <> renderAlias alias

436−

437−-- | @HasUnique alias fields field@ is a constraint that proves that

438−-- @fields@ is a singleton of @alias ::: field@.

439−type HasUnique alias fields field = fields ~ '[alias ::: field]

440−

441−-- | @Has alias fields field@ is a constraint that proves that

442−-- @fields@ has a field of @alias ::: field@, inferring @field@

443−-- from @alias@ and @fields@.

444−class KnownSymbol alias =>

445− Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)

446− | alias fields -> field where

447−instance {-# OVERLAPPING #-} KnownSymbol alias

448− => Has alias (alias ::: field ': fields) field

449−instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)

450− => Has alias (field' ': fields) field

451−

452−-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer

453−-- a list of @subfields@.

454−class

455− ( All KnownSymbol aliases

456− ) => HasAll

457− (aliases :: [Symbol])

458− (fields :: [(Symbol,kind)])

459− (subfields :: [(Symbol,kind)])

460− | aliases fields -> subfields where

461−instance {-# OVERLAPPING #-} HasAll '[] fields '[]

462−instance {-# OVERLAPPABLE #-}

463− (Has alias fields field, HasAll aliases fields subfields)

464− => HasAll (alias ': aliases) fields (alias ::: field ': subfields)

465−

466−-- | Analagous to `IsLabel`, the constraint

467−-- `IsQualified` defines `!` for a column alias qualified

468−-- by a table alias.

469−class IsQualified table column expression where

470− (!) :: Alias table -> Alias column -> expression

471− infixl 9 !

472−instance IsQualified table column (Alias table, Alias column) where (!) = (,)

473−

474−-- | @Elem@ is a promoted `Data.List.elem`.

475−type family Elem x xs where

476− Elem x '[] = 'False

477− Elem x (x ': xs) = 'True

478− Elem x (_ ': xs) = Elem x xs

479−

480−-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

481−type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True

482−

483262-- | Numeric Postgres types.

484263type PGNum =

485264 '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]

@@ -490,37 +269,6 @@ type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]

490269-- | Integral Postgres types.

491270type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]

492271

493−-- | Error message helper for displaying unavailable\/unknown\/placeholder type

494−-- variables whose kind is known.

495−type Placeholder k = 'Text "(_::" :<>: 'ShowType k :<>: 'Text ")"

496−

497−type ErrArrayOf arr ty = arr :<>: 'Text " " :<>: ty

498−type ErrPGfixarrayOf t = ErrArrayOf ('ShowType 'PGfixarray :<>: 'Text " " :<>: Placeholder Nat) t

499−type ErrPGvararrayOf t = ErrArrayOf ('ShowType 'PGvararray) t

500−

501−-- | Ensure a type is a valid array type.

502−type family PGArray name arr :: Constraint where

503− PGArray name ('PGvararray x) = ()

504− PGArray name ('PGfixarray n x) = ()

505− PGArray name val = TypeError

506− ('Text name :<>: 'Text ": Unsatisfied PGArray constraint. Expected either: "

507− :$$: 'Text " • " :<>: ErrPGvararrayOf (Placeholder PGType)

508− :$$: 'Text " • " :<>: ErrPGfixarrayOf (Placeholder PGType)

509− :$$: 'Text "But got: " :<>: 'ShowType val)

510−

511−-- | Ensure a type is a valid array type with a specific element type.

512−type family PGArrayOf name arr ty :: Constraint where

513− PGArrayOf name ('PGvararray x) ty = x ~ ty

514− PGArrayOf name ('PGfixarray n x) ty = x ~ ty

515− PGArrayOf name val ty = TypeError

516− ( 'Text name :<>: 'Text "Unsatisfied PGArrayOf constraint. Expected either: "

517− :$$: 'Text " • " :<>: ErrPGvararrayOf ( 'ShowType ty )

518− :$$: 'Text " • " :<>: ErrPGfixarrayOf ( 'ShowType ty )

519− :$$: 'Text "But got: " :<>: 'ShowType val)

520−

521−-- | Ensure a type is a valid array type whose elements are text.

522−type PGTextArray name arr = PGArrayOf name arr ('NotNull 'PGtext)

523−

524272-- | `PGTypeOf` forgets about @NULL@ and any column constraints.

525273type family PGTypeOf (ty :: NullityType) :: PGType where

526274 PGTypeOf (nullity pg) = pg

@@ -562,12 +310,6 @@ type family NullifyFrom (tables :: FromType) :: FromType where

562310 NullifyFrom (table ::: columns ': tables) =

563311 table ::: NullifyRow columns ': NullifyFrom tables

564312

565−-- | `Join` is simply promoted `++` and is used in @JOIN@s in

566−-- `Squeal.PostgreSQL.Query.FromClause`s.

567−type family Join xs ys where

568− Join '[] ys = ys

569− Join (x ': xs) ys = x ': Join xs ys

570−

571313-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in

572314-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@

573315-- `Squeal.PostgreSQL.Definition.addColumn`.

@@ -587,7 +329,7 @@ type family Drop alias xs where

587329 Drop alias (x ': xs) = x ': Drop alias xs

588330

589331-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@

590−-- with the type `x` and is used in `Squeal.PostgreSQL.Definition.alterTable`

332+-- with the type @x@ and is used in `Squeal.PostgreSQL.Definition.alterTable`

591333-- and `Squeal.PostgreSQL.Definition.alterColumn`.

592334type family Alter alias x xs where

593335 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

@@ -616,16 +358,6 @@ type family DropIfConstraintsInvolve column constraints where

616358 (DropIfConstraintsInvolve column constraints)

617359 (alias ::: constraint ': DropIfConstraintsInvolve column constraints)

618360

619−{- | Calculate the `Length` of a type level list

620−

621−>>> :kind! Length '[Char,String,Bool,Double]

622−Length '[Char,String,Bool,Double] :: Nat

623−= 4

624−-}

625−type family Length (xs :: [k]) :: Nat where

626− Length (x : xs) = 1 + Length xs

627− Length '[] = 0

628−

629361-- | A `SchemumType` is a user-defined type, either a `Table`,

630362-- `View` or `Typedef`.

631363data SchemumType

@@ -657,6 +389,27 @@ type family Schema :: SchemaType where

657389-}

658390type SchemaType = [(Symbol,SchemumType)]

659391

392+{- |

393+A database contains one or more named schemas, which in turn contain tables.

394+The same object name can be used in different schemas without conflict;

395+for example, both schema1 and myschema can contain tables named mytable.

396+Unlike databases, schemas are not rigidly separated:

397+a user can access objects in any of the schemas in the database they are connected to,

398+if they have privileges to do so.

399+

400+There are several reasons why one might want to use schemas:

401+

402+ * To allow many users to use one database without interfering with each other.

403+ * To organize database objects into logical groups to make them more manageable.

404+ * Third-party applications can be put into separate schemas

405+ so they do not collide with the names of other objects.

406+-}

407+type SchemasType = [(Symbol,SchemaType)]

408+

409+-- | A type family to use for a single schema database.

410+type family Public (schema :: SchemaType) :: SchemasType

411+ where Public schema = '["public" ::: schema]

412+

660413-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas

661414-- the overloaded label, `fromLabel` is used for column references,

662415-- `label`s are used for enum terms. A `label` is called with

@@ -668,195 +421,13 @@ instance labels ~ '[label]

668421 => IsPGlabel label (NP PGlabel labels) where label = PGlabel :* Nil

669422-- | A `PGlabel` unit type with an `IsPGlabel` instance

670423data PGlabel (label :: Symbol) = PGlabel

671−-- | Renders a label

672−renderLabel :: KnownSymbol label => proxy label -> ByteString

673−renderLabel (_ :: proxy label) =

674− "\'" <> renderSymbol @label <> "\'"

675−-- | Renders a list of labels

676−renderLabels

677− :: All KnownSymbol labels => NP PGlabel labels -> [ByteString]

678−renderLabels = hcollapse

679− . hcmap (Proxy @KnownSymbol) (K . renderLabel)

680−

681−{- | The `PG` type family embeds a subset of Haskell types

682−as Postgres types. As an open type family, `PG` is extensible.

683−

684−>>> :kind! PG LocalTime

685−PG LocalTime :: PGType

686−= 'PGtimestamp

687−

688−>>> newtype MyDouble = My Double

689−>>> type instance PG MyDouble = 'PGfloat8

690−-}

691−type family PG (hask :: Type) :: PGType

692−type instance PG Bool = 'PGbool

693−type instance PG Int16 = 'PGint2

694−type instance PG Int32 = 'PGint4

695−type instance PG Int64 = 'PGint8

696−type instance PG Word16 = 'PGint2

697−type instance PG Word32 = 'PGint4

698−type instance PG Word64 = 'PGint8

699−type instance PG Scientific = 'PGnumeric

700−type instance PG Float = 'PGfloat4

701−type instance PG Double = 'PGfloat8

702−type instance PG Char = 'PGchar 1

703−type instance PG Text = 'PGtext

704−type instance PG Lazy.Text = 'PGtext

705−type instance PG String = 'PGtext

706−type instance PG ByteString = 'PGbytea

707−type instance PG Lazy.ByteString = 'PGbytea

708−type instance PG LocalTime = 'PGtimestamp

709−type instance PG UTCTime = 'PGtimestamptz

710−type instance PG Day = 'PGdate

711−type instance PG TimeOfDay = 'PGtime

712−type instance PG (TimeOfDay, TimeZone) = 'PGtimetz

713−type instance PG DiffTime = 'PGinterval

714−type instance PG UUID = 'PGuuid

715−type instance PG (NetAddr IP) = 'PGinet

716−type instance PG Value = 'PGjson

717−type instance PG (Json hask) = 'PGjson

718−type instance PG (Jsonb hask) = 'PGjsonb

719−type instance PG (Vector hask) = 'PGvararray (NullPG hask)

720−type instance PG (hask, hask) = 'PGfixarray 2 (NullPG hask)

721−type instance PG (hask, hask, hask) = 'PGfixarray 3 (NullPG hask)

722−type instance PG (hask, hask, hask, hask) = 'PGfixarray 4 (NullPG hask)

723−type instance PG (hask, hask, hask, hask, hask) = 'PGfixarray 5 (NullPG hask)

724−type instance PG (hask, hask, hask, hask, hask, hask)

725− = 'PGfixarray 6 (NullPG hask)

726−type instance PG (hask, hask, hask, hask, hask, hask, hask)

727− = 'PGfixarray 7 (NullPG hask)

728−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask)

729− = 'PGfixarray 8 (NullPG hask)

730−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask, hask)

731− = 'PGfixarray 9 (NullPG hask)

732−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask, hask, hask)

733− = 'PGfixarray 10 (NullPG hask)

734−type instance PG (Composite hask) = 'PGcomposite (RowPG hask)

735−type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)

736−

737−{- | The `Json` newtype is an indication that the Haskell

738−type it's applied to should be stored as `PGjson`.

739−-}

740−newtype Json hask = Json {getJson :: hask}

741− deriving (Eq, Ord, Show, Read, GHC.Generic)

742−

743−{- | The `Jsonb` newtype is an indication that the Haskell

744−type it's applied to should be stored as `PGjsonb`.

745−-}

746−newtype Jsonb hask = Jsonb {getJsonb :: hask}

747− deriving (Eq, Ord, Show, Read, GHC.Generic)

748−

749−{- | The `Composite` newtype is an indication that the Haskell

750−type it's applied to should be stored as a `PGcomposite`.

751−-}

752−newtype Composite record = Composite {getComposite :: record}

753− deriving (Eq, Ord, Show, Read, GHC.Generic)

754−

755−{- | The `Enumerated` newtype is an indication that the Haskell

756−type it's applied to should be stored as `PGenum`.

757−-}

758−newtype Enumerated enum = Enumerated {getEnumerated :: enum}

759− deriving (Eq, Ord, Show, Read, GHC.Generic)

760−

761−{-| The `LabelsPG` type family calculates the constructors of a

762−Haskell enum type.

763−

764−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

765−>>> instance Generic Schwarma

766−>>> instance HasDatatypeInfo Schwarma

767−>>> :kind! LabelsPG Schwarma

768−LabelsPG Schwarma :: [Type.ConstructorName]

769−= '["Beef", "Lamb", "Chicken"]

770−-}

771−type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where

772− LabelsPG hask =

773− ConstructorNamesOf (ConstructorsOf (DatatypeInfoOf hask))

774−

775−{- | `RowPG` turns a Haskell record type into a `RowType`.

776−

777−>>> data Person = Person { name :: Text, age :: Int32 } deriving GHC.Generic

778−>>> instance Generic Person

779−>>> instance HasDatatypeInfo Person

780−>>> :kind! RowPG Person

781−RowPG Person :: [(Symbol, NullityType)]

782−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

783−-}

784−type family RowPG (hask :: Type) :: RowType where

785− RowPG hask = RowOf (RecordCodeOf hask)

786−

787−type family RowOf (fields :: [(Symbol, Type)]) :: RowType where

788− RowOf '[] = '[]

789− RowOf (field ': fields) = FieldPG field ': RowOf fields

790−

791−type family FieldPG (field :: (Symbol, Type)) :: (Symbol, NullityType) where

792− FieldPG (field ::: hask) = field ::: NullPG hask

793−

794−{- | `NullPG` turns a Haskell type into a `NullityType`.

795−

796−>>> :kind! NullPG Double

797−NullPG Double :: NullityType

798−= 'NotNull 'PGfloat8

799−>>> :kind! NullPG (Maybe Double)

800−NullPG (Maybe Double) :: NullityType

801−= 'Null 'PGfloat8

802−-}

803−type family NullPG (hask :: Type) :: NullityType where

804− NullPG (Maybe hask) = 'Null (PG hask)

805− NullPG hask = 'NotNull (PG hask)

806−

807−{- | `TuplePG` turns a Haskell tuple type (including record types) into

808−the corresponding list of `NullityType`s.

809−

810−>>> :kind! TuplePG (Double, Maybe Char)

811−TuplePG (Double, Maybe Char) :: [NullityType]

812−= '['NotNull 'PGfloat8, 'Null ('PGchar 1)]

813−-}

814−type family TuplePG (hask :: Type) :: [NullityType] where

815− TuplePG hask = TupleOf (TupleCodeOf hask (Code hask))

816−

817−type family TupleOf (tuple :: [Type]) :: [NullityType] where

818− TupleOf '[] = '[]

819− TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple

820−

821−type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where

822− TupleCodeOf hask '[tuple] = tuple

823− TupleCodeOf hask '[] =

824− TypeError

825− ( 'Text "The type `" :<>: 'ShowType hask :<>: 'Text "' is not a tuple type."

826− :$$: 'Text "It is a void type with no constructors."

827− )

828− TupleCodeOf hask (_ ': _ ': _) =

829− TypeError

830− ( 'Text "The type `" :<>: 'ShowType hask :<>: 'Text "' is not a tuple type."

831− :$$: 'Text "It is a sum type with more than one constructor."

832− )

833−

834−-- | Calculates constructors of a datatype.

835−type family ConstructorsOf (datatype :: Type.DatatypeInfo)

836− :: [Type.ConstructorInfo] where

837− ConstructorsOf ('Type.ADT _module _datatype constructors) =

838− constructors

839− ConstructorsOf ('Type.Newtype _module _datatype constructor) =

840− '[constructor]

841−

842−-- | Calculates the name of a nullary constructor, otherwise

843−-- generates a type error.

844−type family ConstructorNameOf (constructors :: Type.ConstructorInfo)

845− :: Type.ConstructorName where

846− ConstructorNameOf ('Type.Constructor name) = name

847− ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError

848− ('Text "ConstructorNameOf error: non-nullary constructor "

849− ':<>: 'Text name)

850− ConstructorNameOf ('Type.Record name _fields) = TypeError

851− ('Text "ConstructorNameOf error: non-nullary constructor "

852− ':<>: 'Text name)

853−

854−-- | Calculate the names of nullary constructors.

855−type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])

856− :: [Type.ConstructorName] where

857− ConstructorNamesOf '[] = '[]

858− ConstructorNamesOf (constructor ': constructors) =

859− ConstructorNameOf constructor ': ConstructorNamesOf constructors

424+instance KnownSymbol label => RenderSQL (PGlabel label) where

425+ renderSQL _ = "\'" <> renderSymbol @label <> "\'"

426+instance All KnownSymbol labels => RenderSQL (NP PGlabel labels) where

427+ renderSQL

428+ = commaSeparated

429+ . hcollapse

430+ . hcmap (Proxy @KnownSymbol) (K . renderSQL)

860431

861432-- | Is a type a valid JSON key?

862433type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]

@@ -864,17 +435,15 @@ type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]

864435-- | Is a type a valid JSON type?

865436type PGJsonType = '[ 'PGjson, 'PGjsonb ]

866437

867−-- | An `AlignedList` is a type-aligned list or free category.

868−data AlignedList p x0 x1 where

869− Done :: AlignedList p x x

870− (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2

871−infixr 7 :>>

872−instance Category (AlignedList p) where

873− id = Done

874− (.) list = \case

875− Done -> list

876− step :>> steps -> step :>> (steps >>> list)

877−

878−-- | A `single` step.

879−single :: p x0 x1 -> AlignedList p x0 x1

880−single step = step :>> Done

438+-- | Utility class for `AllUnique` to provide nicer error messages.

439+class IsNotElem x isElem where

440+instance IsNotElem x 'False where

441+instance (TypeError ( 'Text "Cannot assign to "

442+ ':<>: 'ShowType alias

443+ ':<>: 'Text " more than once"))

444+ => IsNotElem '(alias, a) 'True where

445+

446+-- | No elem of @xs@ appears more than once, in the context of assignment.

447+class AllUnique (xs :: [(Symbol, a)]) where

448+instance AllUnique '[] where

449+instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where

squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+98−72

@@ -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

@@ -20,88 +20,114 @@ 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

3132 , longRunningMode

3233 , IsolationLevel (..)

33− , renderIsolationLevel

3434 , AccessMode (..)

35− , renderAccessMode

3635 , DeferrableMode (..)

37− , renderDeferrableMode

3836 ) where

3937

40−import Control.Exception.Lifted

41−import Control.Monad.Base

42−import Control.Monad.Trans.Control

43−import Data.ByteString

44−import Generics.SOP

45−

46−import qualified Database.PostgreSQL.LibPQ as LibPQ

38+import UnliftIO

4739

4840import Squeal.PostgreSQL.Manipulation

4941import Squeal.PostgreSQL.Render

5042import Squeal.PostgreSQL.PQ

51−import Squeal.PostgreSQL.Schema

5243

53−-- | 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+-}

5450transactionally

55− :: (MonadBaseControl IO tx, MonadPQ schema tx)

51+ :: (MonadUnliftIO tx, MonadPQ schemas tx)

5652 => TransactionMode

5753 -> tx x -- ^ run inside a transaction

5854 -> tx x

5955transactionally mode tx = mask $ \restore -> do

60− _ <- begin mode

61− result <- restore tx `onException` rollback

62− _ <- commit

56+ manipulate_ $ begin mode

57+ result <- restore tx `onException` (manipulate_ rollback)

58+ manipulate_ commit

6359 return result

6460

65−-- | Run a schema invariant computation `transactionally_` in `defaultMode`.

61+-- | Run a computation `transactionally_`, in `defaultMode`.

6662transactionally_

67− :: (MonadBaseControl IO tx, MonadPQ schema tx)

63+ :: (MonadUnliftIO tx, MonadPQ schemas tx)

6864 => tx x -- ^ run inside a transaction

6965 -> tx x

7066transactionally_ = transactionally defaultMode

7167

72−-- | @BEGIN@ a transaction.

73−begin :: MonadPQ schema tx => TransactionMode -> tx (K Result ('[] :: RowType))

74−begin mode = manipulate . UnsafeManipulation $

75− "BEGIN" <+> renderTransactionMode 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

76112

77−-- | @COMMIT@ a schema invariant transaction.

78−commit :: MonadPQ schema tx => tx (K Result ('[] :: RowType))

79−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

80123

81−-- | @ROLLBACK@ a schema invariant transaction.

82−rollback :: MonadPQ schema tx => tx (K Result ('[] :: RowType))

83−rollback = manipulate $ UnsafeManipulation "ROLLBACK;"

124+-- | @COMMIT@ a transaction.

125+commit :: Manipulation_ schemas () ()

126+commit = UnsafeManipulation "COMMIT"

84127

85−-- | Run a schema changing computation `transactionallySchema`.

86−transactionallySchema

87− :: MonadBaseControl IO io

88− => TransactionMode

89− -> PQ schema0 schema1 io x

90− -> PQ schema0 schema1 io x

91−transactionallySchema mode u = PQ $ \ conn -> mask $ \ restore -> do

92− _ <- liftBase . LibPQ.exec (unK conn) $

93− "BEGIN" <+> renderTransactionMode mode <> ";"

94− x <- restore (unPQ u conn)

95− `onException` (liftBase (LibPQ.exec (unK conn) "ROLLBACK"))

96− _ <- liftBase $ LibPQ.exec (unK conn) "COMMIT"

97− return x

98−

99−-- | Run a schema changing computation `transactionallySchema_` in `DefaultMode`.

100−transactionallySchema_

101− :: MonadBaseControl IO io

102− => PQ schema0 schema1 io x

103− -> PQ schema0 schema1 io x

104−transactionallySchema_ = transactionallySchema defaultMode

128+-- | @ROLLBACK@ a transaction.

129+rollback :: Manipulation_ schemas () ()

130+rollback = UnsafeManipulation "ROLLBACK"

105131

106132-- | The available transaction characteristics are the transaction `IsolationLevel`,

107133-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.

@@ -114,7 +140,7 @@ data TransactionMode = TransactionMode

114140-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

115141-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.

116142defaultMode :: TransactionMode

117−defaultMode = TransactionMode Serializable ReadWrite NotDeferrable

143+defaultMode = TransactionMode ReadCommitted ReadWrite NotDeferrable

118144

119145-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

120146-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.

@@ -123,12 +149,12 @@ longRunningMode :: TransactionMode

123149longRunningMode = TransactionMode Serializable ReadOnly Deferrable

124150

125151-- | Render a `TransactionMode`.

126−renderTransactionMode :: TransactionMode -> ByteString

127−renderTransactionMode mode =

128− "ISOLATION LEVEL"

129− <+> renderIsolationLevel (isolationLevel mode)

130− <+> renderAccessMode (accessMode mode)

131− <+> renderDeferrableMode (deferrableMode mode)

152+instance RenderSQL TransactionMode where

153+ renderSQL mode =

154+ "ISOLATION LEVEL"

155+ <+> renderSQL (isolationLevel mode)

156+ <+> renderSQL (accessMode mode)

157+ <+> renderSQL (deferrableMode mode)

132158

133159-- | The SQL standard defines four levels of transaction isolation.

134160-- The most strict is `Serializable`, which is defined by the standard in a paragraph

@@ -179,12 +205,12 @@ data IsolationLevel

179205 deriving (Show, Eq)

180206

181207-- | Render an `IsolationLevel`.

182−renderIsolationLevel :: IsolationLevel -> ByteString

183−renderIsolationLevel = \case

184− Serializable -> "SERIALIZABLE"

185− ReadCommitted -> "READ COMMITTED"

186− ReadUncommitted -> "READ UNCOMMITTED"

187− RepeatableRead -> "REPEATABLE READ"

208+instance RenderSQL IsolationLevel where

209+ renderSQL = \case

210+ Serializable -> "SERIALIZABLE"

211+ ReadCommitted -> "READ COMMITTED"

212+ ReadUncommitted -> "READ UNCOMMITTED"

213+ RepeatableRead -> "REPEATABLE READ"

188214

189215-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.

190216-- `ReadWrite` is the default. When a transaction is `ReadOnly`,

@@ -201,10 +227,10 @@ data AccessMode

201227 deriving (Show, Eq)

202228

203229-- | Render an `AccessMode`.

204−renderAccessMode :: AccessMode -> ByteString

205−renderAccessMode = \case

206− ReadWrite -> "READ WRITE"

207− ReadOnly -> "READ ONLY"

230+instance RenderSQL AccessMode where

231+ renderSQL = \case

232+ ReadWrite -> "READ WRITE"

233+ ReadOnly -> "READ ONLY"

208234

209235-- | The `Deferrable` transaction property has no effect

210236-- unless the transaction is also `Serializable` and `ReadOnly`.

@@ -220,7 +246,7 @@ data DeferrableMode

220246 deriving (Show, Eq)

221247

222248-- | Render a `DeferrableMode`.

223−renderDeferrableMode :: DeferrableMode -> ByteString

224−renderDeferrableMode = \case

225− Deferrable -> "DEFERRABLE"

226− NotDeferrable -> "NOT DEFERRABLE"

249+instance RenderSQL DeferrableMode where

250+ renderSQL = \case

251+ Deferrable -> "DEFERRABLE"

252+ NotDeferrable -> "NOT DEFERRABLE"

squeal-postgresql/test/Specs/ExceptionHandling.hs+23−19

@@ -7,6 +7,7 @@

77{-# LANGUAGE OverloadedStrings #-}

88{-# LANGUAGE TypeApplications #-}

99{-# LANGUAGE TypeFamilies #-}

10+{-# LANGUAGE TypeInType #-}

1011{-# LANGUAGE TypeOperators #-}

1112module ExceptionHandling

1213 ( specs

@@ -15,7 +16,7 @@ module ExceptionHandling

1516where

1617

1718import Control.Monad (void)

18−import Control.Monad.Base (MonadBase)

19+import Control.Monad.IO.Class (MonadIO (..))

1920import qualified Data.ByteString.Char8 as Char8

2021import Data.Int (Int16)

2122import Data.Text (Text)

@@ -23,7 +24,6 @@ import Data.Vector (Vector)

2324import qualified Generics.SOP as SOP

2425import qualified GHC.Generics as GHC

2526import Squeal.PostgreSQL

26−import Squeal.PostgreSQL.Migration

2727import Test.Hspec

2828

2929type Schema =

@@ -45,21 +45,23 @@ type Schema =

4545 ])

4646 ]

4747

48+type Schemas = Public Schema

49+

4850data User =

4951 User { userName :: Text

5052 , userEmail :: Maybe Text

51− , userVec :: Vector (Maybe Int16) }

53+ , userVec :: VarArray (Vector (Maybe Int16)) }

5254 deriving (Show, GHC.Generic)

5355instance SOP.Generic User

5456instance SOP.HasDatatypeInfo User

5557

56−insertUser :: Manipulation Schema '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]

58+insertUser :: Manipulation '[] Schemas '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]

5759 '[ "fromOnly" ::: 'NotNull 'PGint4 ]

58−insertUser = insertRows #users

59− (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec) []

60+insertUser = insertInto #users

61+ (Values_ (Default `as` #id :* Set (param @1) `as` #name :* Set (param @2) `as` #vec))

6062 OnConflictDoRaise (Returning (#id `as` #fromOnly))

6163

62−setup :: Definition '[] Schema

64+setup :: Definition (Public '[]) Schemas

6365setup =

6466 createTable #users

6567 ( serial `as` #id :*

@@ -76,32 +78,34 @@ setup =

7678 foreignKey #user_id #users #id

7779 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

7880

79−teardown :: Definition Schema '[]

81+teardown :: Definition Schemas (Public '[])

8082teardown = dropTable #emails >>> dropTable #users

8183

82−migration :: Migration IO '[] Schema

84+migration :: Migration Definition (Public '[]) Schemas

8385migration = Migration { name = "test"

84− , up = void $ define setup

85− , down = void $ define teardown }

86+ , up = setup

87+ , down = teardown }

8688

8789setupDB :: IO ()

88−setupDB = void . withConnection connectionString $

89− migrateUp $ single migration

90+setupDB = withConnection connectionString $

91+ manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")

92+ & pqThen (migrateUp (single migration))

9093

9194dropDB :: IO ()

92−dropDB = void . withConnection connectionString $

93− migrateDown $ single migration

95+dropDB = withConnection connectionString $

96+ manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")

97+ & pqThen (migrateDown (single migration))

9498

9599connectionString :: Char8.ByteString

96100connectionString = "host=localhost port=5432 dbname=exampledb"

97101

98102testUser :: User

99−testUser = User "TestUser" Nothing []

103+testUser = User "TestUser" Nothing (VarArray [])

100104

101−newUser :: (MonadBase IO m, MonadPQ Schema m) => User -> m ()

105+newUser :: (MonadIO m, MonadPQ Schemas m) => User -> m ()

102106newUser u = void $ manipulateParams insertUser (userName u, userVec u)

103107

104−insertUserTwice :: (MonadBase IO m, MonadPQ Schema m) => m ()

108+insertUserTwice :: (MonadIO m, MonadPQ Schemas m) => m ()

105109insertUserTwice = newUser testUser >> newUser testUser

106110

107111specs :: SpecWith ()

@@ -109,7 +113,7 @@ specs = before_ setupDB $ after_ dropDB $

109113 describe "Exceptions" $ do

110114

111115 let

112− dupKeyErr = PQException FatalError (Just "23505")

116+ dupKeyErr = PQException $ PQState FatalError (Just "23505")

113117 (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")

114118

115119 it "should be thrown for unique constraint violation in a manipulation" $

squeal-presentation-2018-09-12.html → squeal-presentation-raveline.mdrenamed+30−112

@@ -1,46 +1,8 @@

1−<!DOCTYPE html>

2−<html>

3−<head>

4− <title>Title</title>

5− <meta charset="utf-8">

6− <style>

7− @import url(https://fonts.googleapis.com/css?family=PT+Sans+Narrow);

8− @import url(https://fonts.googleapis.com/css?family=Montserrat:400,700,400italic);

9− @import url(https://fonts.googleapis.com/css?family=Ubuntu+Mono:400,700,400italic);

10−

11− body { font-family: 'Montserrat'; }

12− h1, h2, h3 {

13− font-family: 'PT Sans Narrow';

14− font-weight: normal;

15− }

16−

17− .note {

18− background-color: #ccc;

19− padding: 1rem;

20− border-radius: 4px;

21− }

22− .remark-code, .remark-inline-code { font-family: 'Ubuntu Mono'; }

23−

24− .signature {

25− position: absolute;

26− top: 1%;

27− right: 1%;

28− font-size:.6em;

29− opacity: .5;

30− }

31− </style>

32− </head>

33− <body>

34− <textarea id="source">

35−

36−class: center, middle

37−count: false

38−

391# Squeal

402

413_A bridge between SQL and Haskell_

424

43−.signature[2018/09/12 - by @Raveline]

5+by [@Raveline](https://github.com/raveline)

446

457---

468

@@ -62,9 +24,6 @@ Using `postgresql-simple` you have a typical "Trial, error, despair" workflow:

6224

6325---

6426

65−class: center, middle

66−count: false

67−

6827![Can't take this anymore](http://gif.eraveline.eu/static/img/0x16e.gif)

6928

7029---

@@ -85,9 +44,6 @@ However, it's not an ORM. There's no caching, lazy loading - you retain control

8544

8645---

8746

88−class: center, middle

89−count: false

90−

9147# Part I. Schema & migration

9248

9349---

@@ -107,16 +63,13 @@ type Schema = '[ "mp" ::: 'Table MemberOfParliament

10763 , "groupp" ::: 'Table ParliamentGroup ]

10864```

10965

110−--

66+---

11167

112−.note[*

113−We need the `DataKinds` extension to be able to express heterogenous lists containing

114−specific types like this one.

68+> _note_ We need the `DataKinds` extension to be able to express heterogenous lists containing

69+> specific types like this one.

11570

116−*

117−You can perfectly call your table "group" and not "groupp" even though it is a

118−keyword in SQL - Squeal queries will be properly escaped.

119−]

71+> You can perfectly call your table "group" and not "groupp" even though it is a

72+> keyword in SQL - Squeal queries will be properly escaped.

12073

12174---

12275

@@ -139,17 +92,13 @@ type ParliamentaryGroup =

13992

14093- Let's split constraints and column to study the syntax a bit more.

14194

142−--

95+---

14396

144−.note[*

145−We are using `:::` and `:=>` to quickly express associations when writing

146−our schema. We need the `TypeOperators` extension.]

97+> _note_ We are using `:::` and `:=>` to quickly express associations when writing

98+> our schema. We need the `TypeOperators` extension.]

14799

148100---

149101

150−class: center, middle

151−count: false

152−

153102![What does this means ?!](http://gif.eraveline.eu/static/img/0x27e.gif)

154103

155104---

@@ -195,10 +144,10 @@ type MpCols =

195144

196145 * the type (obviously).

197146

198−--

147+---

199148

200−.note[*

201−GHC is already helping. If I named the "mp_id" column differently, GHC would yell because I promised a primary key constraint on a column named `mp_id`, so there must be one.]

149+> _note_ GHC is already helping. If I named the "mp_id" column differently,

150+> GHC would yell because I promised a primary key constraint on a column named `mp_id`, so there must be one.]

202151

203152---

204153

@@ -208,7 +157,7 @@ GHC is already helping. If I named the "mp_id" column differently, GHC would yel

208157

209158- But before we play with this schema, we need to implement it.

210159

211−--

160+---

212161

213162```haskell

214163setup :: Definition '[] Schema

@@ -240,15 +189,14 @@ setup =

240189

241190- You use `>>>` to compose table creation.

242191

243−- Note that the compiler will catch any mistype between Schema and

244−definition; wrong nullability, wrong type, wrong name, etc.

192+> _note_ The compiler will catch any mistype between Schema and

193+> definition; wrong nullability, wrong type, wrong name, etc.

245194

246−--

195+---

247196

248−.note[*

249−You'll also need `OverloadedLabels`, for naming stuff.

250−This is mostly to avoid having to write manual proxies all

251−the time and for convenience.]

197+> _note_ You'll also need `OverloadedLabels`, for naming stuff.

198+> This is mostly to avoid having to write manual proxies all

199+> the time and for convenience.

252200

253201---

254202

@@ -283,8 +231,8 @@ tearDown :: Definition Schema '[]

283231tearDown = dropTable #mp >>> dropTable #groupp

284232```

285233

286−- Note that GHC will also detect the _proper_ order of what you typed in

287− downgrade and upgrade should there be any conflict (with foreign keys).

234+> _note_ GHC will also detect the _proper_ order of what you typed in

235+> downgrade and upgrade should there be any conflict (with foreign keys).

288236

289237```haskell

290238initDB :: Migration IO '[] Schema

@@ -314,16 +262,10 @@ main = do

314262

315263---

316264

317−class: center, middle

318−count: false

319−

320265![That was easy](http://gif.eraveline.eu/static/img/0x47f.gif)

321266

322267---

323268

324−class: center, middle

325−count: false

326−

327269# Part II. Insertions

328270

329271---

@@ -369,9 +311,8 @@ data MemberOfParliament =

369311 , lastName :: Text }

370312```

371313

372−- You'll note that we didn't use anything from Squeal.

373−

374−- The model can be entirely separated from the persistence layer.

314+> _note_ We didn't use anything from Squeal.

315+> The model can be entirely separated from the persistence layer.

375316

376317---

377318

@@ -386,7 +327,7 @@ type GroupInsertionParams = '[ 'NotNull 'PGuuid

386327

387328- Params are not named, but they are indexed. You just need nullability and type.

388329

389−--

330+---

390331

391332```haskell

392333groupInsertion :: Manipulation Schema GroupInsertionParams '[]

@@ -395,7 +336,7 @@ groupInsertion =

395336 :* Set (param @2) `as` #name )

396337```

397338

398−--

339+---

399340

400341- `TypeApplication` lets us use the index of parameters (counting from 1).

401342

@@ -410,19 +351,19 @@ _Inserting a Member of Parliament_

410351

411352- We could create a naive query that takes MP uuid, first name, last name and group uuid...

412353

413−--

354+---

414355

415356- But that's boring. So let's use the `INSERT INTO ... SELECT`.

416357

417−--

358+---

418359

419360- We will build a query that will return as constants our MP's uuid, first name and last name...

420361

421−--

362+---

422363

423364- ... and fetch the uuid of a group given the name of the group.

424365

425−--

366+---

426367

427368- There's a `insertQuery` utility function for that. All we have to do is write the `select` !

428369

@@ -572,16 +513,11 @@ insertParliament = traverse_ insertGroup

572513

573514---

574515

575−class: center, middle

576−count: false

577−

578516![Very simple](https://media1.tenor.com/images/0188c63209aced59f1583e1ca94e509e/tenor.gif?itemid=3550689)

579517

580518

581519---

582520

583−class: center, middle

584−

585521# Part III. Selects

586522

587523---

@@ -653,7 +589,7 @@ type BaseParliamentSelection =

653589 , "m" ::: TableToRow MpCols ]

654590```

655591

656−- Note that we've also put everything with table aliases: "g" and "m".

592+> _note_ We've also put everything with table aliases: "g" and "m".

657593

658594---

659595

@@ -831,16 +767,10 @@ getGroupMembers =

831767

832768---

833769

834−class: center, middle

835−count: false

836−

837770![Eazy](https://media.tenor.com/images/8fc7c4077efe11b4a3a3b9ae4e643e87/tenor.gif)

838771

839772---

840773

841−class: center, middle

842−count: false

843−

844774# Conclusion

845775

846776---

@@ -860,17 +790,5 @@ count: false

860790- Typesafe. 'nuff said.

861791

862792---

863−class: center, middle

864−count: false

865793

866794# Thank you !

867−

868−

869− </textarea>

870− <script src="https://remarkjs.com/downloads/remark-latest.min.js">

871− </script>

872− <script>

873− var slideshow = remark.create({countIncrementalSlides: false});

874− </script>

875− </body>

876−</html>

stack.yaml+4−1

@@ -1,3 +1,6 @@

1−resolver: nightly-2018-09-03

1+resolver: lts-13.8

22packages:

33- squeal-postgresql

5+extra-deps:

6+- unliftio-pool-0.2.1.0