ca38686...dev · squeal

git.iko.soy/squeal

53 files changed+10196−5269

since splitsnapshots

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:8.6.5

66 - image: circleci/postgres:latest

77 environment:

88 POSTGRES_USER: root

README.md+64−75

@@ -46,7 +46,11 @@ composable and cover a large portion of SQL.

4646* transactions

4747* views

4848* array, composite and enumerated types

49−* json operations

49+* json functions and operations

50+* multischema support

51+* correlated subqueries

52+* window functions

53+* text search

5054

5155## installation

5256

@@ -72,19 +76,17 @@ First, we need some language extensions because Squeal uses modern GHC

7276features.

7377

7478```Haskell

75−>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels

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

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

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

7781```

7882

7983We'll need some imports.

8084

8185```Haskell

82−>>> import Control.Monad (void)

83−>>> import Control.Monad.Base (liftBase)

86+>>> import Control.Monad.IO.Class (liftIO)

8487>>> import Data.Int (Int32)

8588>>> import Data.Text (Text)

8689>>> import Squeal.PostgreSQL

87−>>> import Squeal.PostgreSQL.Render

8890```

8991

9092We'll use generics to easily convert between Haskell and PostgreSQL values.

@@ -99,27 +101,27 @@ we use `DataKinds` and `TypeOperators`.

99101

100102```Haskell

101103>>> :{

104+type UsersColumns =

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

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

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

108+type EmailsColumns =

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

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

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

112+type EmailsConstraints =

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

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

102115type Schema =

103− '[ "users" ::: 'Table (

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

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

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

107− ])

108− , "emails" ::: 'Table (

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

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

111− ] :=>

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

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

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

115− ])

116− ]

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

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

118+type Schemas = Public Schema

117119:}

118120```

119121

120122Notice the use of type operators.

121123

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

124+`:::` is used to pair an alias `Symbol` with a `SchemumType`,

123125a `TableConstraint` or a `ColumnType`. It is intended to connote Haskell's `::`

124126operator.

125127

@@ -128,7 +130,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

128130yielding a `ColumnType`. It is intended to connote Haskell's `=>` operator

129131

130132Next, we'll write `Definition`s to set up and tear down the schema. In

131−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`

133+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`

132134has two type parameters, corresponding to the schema

133135before being run and the schema after. We can compose definitions using `>>>`.

134136Here and in the rest of our commands we make use of overloaded

@@ -137,8 +139,8 @@ labels to refer to named tables and columns in our schema.

137139```Haskell

138140>>> :{

139141let

140− setup :: Definition '[] Schema

141− setup =

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

143+ setup =

142144 createTable #users

143145 ( serial `as` #id :*

144146 (text & notNullable) `as` #name )

@@ -169,7 +171,7 @@ primary and foreign keys, making them somewhat complex. Our `teardown`

169171```Haskell

170172>>> :{

171173let

172− teardown :: Definition Schema '[]

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

173175 teardown = dropTable #emails >>> dropTable #users

174176:}

175177

@@ -178,54 +180,54 @@ DROP TABLE "emails";

178180DROP TABLE "users";

179181```

180182

181−Next, we'll write `Manipulation`s to insert data into our two tables.

182−A `Manipulation` like `insertRow`, `update` or `deleteFrom`

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

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

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

184+`SOP.HasDatatypeInfo` instances so that we can encode and decode `User`s.

185+

186+```Haskell

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

188+>>> instance SOP.Generic User

189+>>> instance SOP.HasDatatypeInfo User

190+```

191+

192+Next, we'll write `Manipulation_`s to insert `User`s into our two tables.

193+A `Manipulation_` like `insertInto`, `update` or `deleteFrom`

194+has three type parameters, the schemas it refers to, input parameters

195+and an output row. When

185196we insert into the users table, we will need a parameter for the `name`

186197field but not for the `id` field. Since it's serial, we can use a default

187198value. However, since the emails table refers to the users table, we will

188199need to retrieve the user id that the insert generates and insert it into

189−the emails table. Take a careful look at the type and definition of both

190−of our inserts.

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

201+`with` statement.

191202

192203```Haskell

193204>>> :{

194205let

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

196− insertUser = insertRow #users

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

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

199−:}

200−

201−>>> :{

202−let

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

204− insertEmail = insertRow #emails

205− ( Default `as` #id :*

206− Set (param @1) `as` #user_id :*

207− Set (param @2) `as` #email )

208− OnConflictDoNothing (Returning Nil)

206+ insertUser :: Manipulation_ Schemas User ()

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

208+ where

209+ u = insertInto #users

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

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

212+ e = insertInto_ #emails $ Select

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

214+ (from (common #u))

209215:}

210216

211217>>> printSQL insertUser

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

213−>>> printSQL insertEmail

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

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

215219```

216220

217−Next we write a `Query` to retrieve users from the database. We're not

221+Next we write a `Query_` to retrieve users from the database. We're not

218222interested in the ids here, just the usernames and email addresses. We

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

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

223+need to use an `innerJoin` to get the right result. A `Query_` is like a

224+`Manipulation_` with the same kind of type parameters.

221225

222226```Haskell

223227>>> :{

224228let

225− getUsers :: Query Schema '[]

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

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

228− getUsers = select

229+ getUsers :: Query_ Schemas () User

230+ getUsers = select_

229231 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)

230232 ( from (table (#users `as` #u)

231233 & innerJoin (table (#emails `as` #e))

@@ -236,25 +238,13 @@ let

236238SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")

237239```

238240

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

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

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

242−we receive when we run `getUsers`. Notice that the record fields of the

243−`User` type match the column names of `getUsers`.

244−

245−```Haskell

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

247−>>> instance SOP.Generic User

248−>>> instance SOP.HasDatatypeInfo User

249−```

250−

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

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

252242

253243```Haskell

254244>>> :{

255245let

256246 users :: [User]

257− users =

247+ users =

258248 [ User "Alice" (Just "alice@gmail.com")

259249 , User "Bob" Nothing

260250 , User "Carole" (Just "carole@hotmail.com")

@@ -273,19 +263,18 @@ transformer and when the schema doesn't change we can use `Monad` and

273263```Haskell

274264>>> :{

275265let

276− session :: PQ Schema Schema IO ()

266+ session :: PQ Schemas Schemas IO ()

277267 session = do

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

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

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

268+ _ <- traversePrepared_ insertUser users

281269 usersResult <- runQuery getUsers

282270 usersRows <- getRows usersResult

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

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

284272in

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

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

286274 define setup

287275 & pqThen session

288276 & pqThen (define teardown)

289277:}

290278[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]

279+-}

291280```

RELEASE NOTES.md+400

@@ -1,5 +1,405 @@

11## RELEASE NOTES

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+30−37

@@ -11,8 +11,7 @@

1111

1212module Main (main, main2) where

1313

14−import Control.Monad (void)

15−import Control.Monad.Base (liftBase, MonadBase)

14+import Control.Monad.IO.Class (MonadIO (..))

1615import Data.Int (Int16, Int32)

1716import Data.Monoid ((<>))

1817import Data.Text (Text)

@@ -39,14 +38,13 @@ type Schema =

3938 , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

4039 , "email" ::: 'NoDef :=> 'Null 'PGtext

4140 ])

41+ , "positive" ::: 'Typedef 'PGfloat4

4242 ]

4343

4444type Schemas = Public Schema

4545

46−type DB = DBof Schemas

47−

4846setup :: Definition (Public '[]) Schemas

49−setup =

47+setup =

5048 createTable #users

5149 ( serial `as` #id :*

5250 (text & notNullable) `as` #name :*

@@ -55,60 +53,55 @@ setup =

5553 >>>

5654 createTable #emails

5755 ( serial `as` #id :*

58− (int & notNullable) `as` #user_id :*

59− (text & nullable) `as` #email )

56+ hask @Int32 `as` #user_id :*

57+ hask @(Maybe Text) `as` #email )

6058 ( primaryKey #id `as` #pk_emails :*

6159 foreignKey #user_id #users #id

6260 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

61+ >>>

62+ createDomain #positive real (#value .> 0 .&& (#value & isNotNull))

6363

6464teardown :: Definition Schemas (Public '[])

65−teardown = dropTable #emails >>> dropTable #users

66−

67−insertUser :: Manipulation DB '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]

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

69−insertUser = insertRows #users

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

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

72−

73−insertEmail :: Manipulation DB '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

74−insertEmail = insertRows #emails

75− ( Default `as` #id :*

76− Set (param @1) `as` #user_id :*

77− Set (param @2) `as` #email ) []

78− OnConflictDoNothing (Returning Nil)

79−

80−getUsers :: Query DB '[]

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

82− , "userEmail" ::: 'Null 'PGtext

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

84−getUsers = select

65+teardown = dropType #positive >>> dropTable #emails >>> dropTable #users

66+

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

68+insertUser = insertInto #users

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

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

71+

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

73+insertEmail = insertInto_ #emails

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

75+

76+getUsers :: Query_ Schemas () User

77+getUsers = select_

8578 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail :* #u ! #vec `as` #userVec)

8679 ( from (table (#users `as` #u)

8780 & innerJoin (table (#emails `as` #e))

8881 (#u ! #id .== #e ! #user_id)) )

8982

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

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

9184 deriving (Show, GHC.Generic)

9285instance SOP.Generic User

9386instance SOP.HasDatatypeInfo User

9487

9588users :: [User]

96−users =

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

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

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

89+users =

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

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

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

10093 ]

10194

102−session :: (MonadBase IO pq, MonadPQ Schemas pq) => pq ()

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

10396session = do

104− liftBase $ Char8.putStrLn "manipulating"

97+ liftIO $ Char8.putStrLn "manipulating"

10598 idResults <- traversePrepared insertUser ([(userName user, userVec user) | user <- users])

10699 ids <- traverse (fmap fromOnly . getRow 0) idResults

107100 traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))

108− liftBase $ Char8.putStrLn "querying"

101+ liftIO $ Char8.putStrLn "querying"

109102 usersResult <- runQuery getUsers

110103 usersRows <- getRows usersResult

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

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

112105

113106main :: IO ()

114107main = do

@@ -126,7 +119,7 @@ main = do

126119

127120main2 :: IO ()

128121main2 =

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

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

130123 define setup

131124 & pqThen session

132125 & pqThen (define teardown)

squeal-postgresql/squeal-postgresql.cabal+58−16

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

11name: squeal-postgresql

2−version: 0.4.0.0

2+version: 0.5.1.0

33synopsis: Squeal PostgreSQL Library

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

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

@@ -22,12 +22,40 @@ library

2222 hs-source-dirs: src

2323 exposed-modules:

2424 Squeal.PostgreSQL

25+ Squeal.PostgreSQL.Alias

2526 Squeal.PostgreSQL.Binary

2627 Squeal.PostgreSQL.Definition

28+ Squeal.PostgreSQL.Definition.Function

29+ Squeal.PostgreSQL.Definition.Index

30+ Squeal.PostgreSQL.Definition.Table

31+ Squeal.PostgreSQL.Definition.Table.Constraint

32+ Squeal.PostgreSQL.Definition.Type

33+ Squeal.PostgreSQL.Definition.Schema

34+ Squeal.PostgreSQL.Definition.View

2735 Squeal.PostgreSQL.Expression

36+ Squeal.PostgreSQL.Expression.Aggregate

37+ Squeal.PostgreSQL.Expression.Collection

38+ Squeal.PostgreSQL.Expression.Comparison

39+ Squeal.PostgreSQL.Expression.Json

40+ Squeal.PostgreSQL.Expression.Literal

41+ Squeal.PostgreSQL.Expression.Logic

42+ Squeal.PostgreSQL.Expression.Math

43+ Squeal.PostgreSQL.Expression.Null

44+ Squeal.PostgreSQL.Expression.Parameter

45+ Squeal.PostgreSQL.Expression.Range

46+ Squeal.PostgreSQL.Expression.Set

47+ Squeal.PostgreSQL.Expression.Sort

48+ Squeal.PostgreSQL.Expression.Subquery

49+ Squeal.PostgreSQL.Expression.Text

50+ Squeal.PostgreSQL.Expression.TextSearch

51+ Squeal.PostgreSQL.Expression.Time

52+ Squeal.PostgreSQL.Expression.Type

53+ Squeal.PostgreSQL.Expression.Window

54+ Squeal.PostgreSQL.List

2855 Squeal.PostgreSQL.Manipulation

2956 Squeal.PostgreSQL.Migration

3057 Squeal.PostgreSQL.Pool

58+ Squeal.PostgreSQL.PG

3159 Squeal.PostgreSQL.PQ

3260 Squeal.PostgreSQL.Render

3361 Squeal.PostgreSQL.Query

@@ -42,10 +70,9 @@ library

4270 , bytestring >= 0.10.8.2

4371 , bytestring-strict-builder >= 0.4.5

4472 , deepseq >= 1.4.3.0

45− , generics-sop >= 0.3.2.0

46− , lifted-base >= 0.2.3.12

73+ , free-categories >= 0.1.0.0

74+ , generics-sop >= 0.3.2.0 && < 0.5.0.0

4775 , mmorph >= 1.1.1

48− , monad-control >= 1.0.2.3

4976 , mtl >= 2.2.2

5077 , network-ip >= 0.3.0.2

5178 , postgresql-binary >= 0.12.1

@@ -56,39 +83,55 @@ library

5683 , text >= 1.2.3.0

5784 , time >= 1.8.0.2

5885 , transformers >= 0.5.2.0

59− , transformers-base >= 0.4.4

86+ , unliftio >= 0.2.10

87+ , unliftio-pool >= 0.2.1.0

6088 , uuid-types >= 1.0.3

6189 , vector >= 0.12.0.1

6290

63−test-suite squeal-postgresql-doctest

91+test-suite doctest

6492 default-language: Haskell2010

6593 type: exitcode-stdio-1.0

6694 hs-source-dirs: test

6795 ghc-options: -Wall

68− main-is: DocTest.hs

96+ main-is: Doc.hs

6997 build-depends:

7098 base >= 4.10.0.0

7199 , doctest >= 0.11.4

100+ , squeal-postgresql

72101

73−test-suite squeal-postgresql-specs

102+test-suite properties

74103 default-language: Haskell2010

75104 type: exitcode-stdio-1.0

76− hs-source-dirs: test/Specs

77− ghc-options: -Wall -main-is Specs

78− main-is: Specs.hs

79− other-modules: ExceptionHandling

105+ hs-source-dirs: test

106+ ghc-options: -Wall

107+ main-is: Property.hs

80108 build-depends:

81109 base >= 4.10.0.0

82110 , bytestring >= 0.10.8.2

111+ , hedgehog >= 1.0

112+ , mtl >= 2.2.2

113+ , scientific >= 0.3.5.3

114+ , squeal-postgresql

115+ , time >= 1.8.0.2

116+

117+test-suite spec

118+ default-language: Haskell2010

119+ type: exitcode-stdio-1.0

120+ hs-source-dirs: test

121+ ghc-options: -Wall

122+ main-is: Spec.hs

123+ build-depends:

124+ base >= 4.10.0.0

125+ , async >= 2.2.2

126+ , bytestring >= 0.10.8.2

83127 , generics-sop >= 0.3.1.0

84128 , hspec >= 2.4.8

129+ , mtl >= 2.2.2

85130 , squeal-postgresql

86131 , text >= 1.2.2.2

87− , transformers >= 0.5.2.0

88− , transformers-base >= 0.4.4

89132 , vector >= 0.12.0.1

90133

91−executable squeal-postgresql-example

134+executable example

92135 default-language: Haskell2010

93136 hs-source-dirs: exe

94137 ghc-options: -Wall

@@ -101,5 +144,4 @@ executable squeal-postgresql-example

101144 , squeal-postgresql

102145 , text >= 1.2.2.2

103146 , transformers >= 0.5.2.0

104− , transformers-base >= 0.4.4

105147 , vector >= 0.12.0.1

squeal-postgresql/src/Squeal/PostgreSQL.hs+82−77

@@ -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

@@ -47,7 +45,6 @@ type Schema =

4745 '[ "users" ::: 'Table (UsersConstraints :=> UsersColumns)

4846 , "emails" ::: 'Table (EmailsConstraints :=> EmailsColumns) ]

4947type Schemas = Public Schema

50−type DB = DBof Schemas

5148:}

5249

5350Notice the use of type operators.

@@ -61,7 +58,7 @@ yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

6158yielding a `ColumnType`. It is intended to connote Haskell's @=>@ operator

6259

6360Next, we'll write `Definition`s to set up and tear down the schema. In

64−Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`

61+Squeal, a `Definition` like `createTable`, `alterTable` or `dropTable`

6562has two type parameters, corresponding to the schema

6663before being run and the schema after. We can compose definitions using `>>>`.

6764Here and in the rest of our commands we make use of overloaded

@@ -70,7 +67,7 @@ labels to refer to named tables and columns in our schema.

7067>>> :{

7168let

7269 setup :: Definition (Public '[]) Schemas

73− setup =

70+ setup =

7471 createTable #users

7572 ( serial `as` #id :*

7673 (text & notNullable) `as` #name )

@@ -105,51 +102,49 @@ let

105102DROP TABLE "emails";

106103DROP TABLE "users";

107104

108−Next, we'll write `Manipulation`s to insert data into our two tables.

109−A `Manipulation` like `insertRow`, `update` or `deleteFrom`

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

111−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

112116we insert into the users table, we will need a parameter for the @name@

113117field but not for the @id@ field. Since it's serial, we can use a default

114118value. However, since the emails table refers to the users table, we will

115119need to retrieve the user id that the insert generates and insert it into

116−the emails table. Take a careful look at the type and definition of both

117−of our inserts.

118−

119−>>> :{

120−let

121− insertUser :: Manipulation DB '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]

122− insertUser = insertRow #users

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

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

125−:}

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

121+`with` statement.

126122

127123>>> :{

128124let

129− insertEmail :: Manipulation DB '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

130− insertEmail = insertRow #emails

131− ( Default `as` #id :*

132− Set (param @1) `as` #user_id :*

133− Set (param @2) `as` #email )

134− 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))

135134:}

136135

137136>>> printSQL insertUser

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

139−>>> printSQL insertEmail

140−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"

141138

142−Next we write a `Query` to retrieve users from the database. We're not

139+Next we write a `Query_` to retrieve users from the database. We're not

143140interested in the ids here, just the usernames and email addresses. We

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

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

141+need to use an `innerJoin` to get the right result. A `Query_` is like a

142+`Manipulation_` with the same kind of type parameters.

146143

147144>>> :{

148145let

149− getUsers :: Query DB '[]

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

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

152− getUsers = select

146+ getUsers :: Query_ Schemas () User

147+ getUsers = select_

153148 (#u ! #name `as` #userName :* #e ! #email `as` #userEmail)

154149 ( from (table (#users `as` #u)

155150 & innerJoin (table (#emails `as` #e))

@@ -159,22 +154,12 @@ let

159154>>> printSQL getUsers

160155SELECT "u"."name" AS "userName", "e"."email" AS "userEmail" FROM "users" AS "u" INNER JOIN "emails" AS "e" ON ("u"."id" = "e"."user_id")

161156

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

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

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

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

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

167−

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

169−>>> instance SOP.Generic User

170−>>> instance SOP.HasDatatypeInfo User

171−

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

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

173158

174159>>> :{

175160let

176161 users :: [User]

177− users =

162+ users =

178163 [ User "Alice" (Just "alice@gmail.com")

179164 , User "Bob" Nothing

180165 , User "Carole" (Just "carole@hotmail.com")

@@ -193,36 +178,56 @@ transformer and when the schema doesn't change we can use `Monad` and

193178let

194179 session :: PQ Schemas Schemas IO ()

195180 session = do

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

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

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

181+ _ <- traversePrepared_ insertUser users

199182 usersResult <- runQuery getUsers

200183 usersRows <- getRows usersResult

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

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

202185in

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

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

204187 define setup

205188 & pqThen session

206189 & pqThen (define teardown)

207190:}

208191[User {userName = "Alice", userEmail = Just "alice@gmail.com"},User {userName = "Bob", userEmail = Nothing},User {userName = "Carole", userEmail = Just "carole@hotmail.com"}]

209192-}

210−module Squeal.PostgreSQL

211− ( module Squeal.PostgreSQL.Binary

212− , module Squeal.PostgreSQL.Definition

213− , module Squeal.PostgreSQL.Expression

214− , module Squeal.PostgreSQL.Manipulation

215− , module Squeal.PostgreSQL.PQ

216− , module Squeal.PostgreSQL.Query

217− , module Squeal.PostgreSQL.Schema

218− , module Squeal.PostgreSQL.Transaction

219− ) where

220−

221−import Squeal.PostgreSQL.Binary

222−import Squeal.PostgreSQL.Definition

223−import Squeal.PostgreSQL.Expression

224−import Squeal.PostgreSQL.Manipulation

225−import Squeal.PostgreSQL.PQ

226−import Squeal.PostgreSQL.Query

227−import Squeal.PostgreSQL.Schema

228−import Squeal.PostgreSQL.Transaction

193+module Squeal.PostgreSQL (module X, RenderSQL(..), printSQL) where

194+

195+import Squeal.PostgreSQL.Alias as X

196+import Squeal.PostgreSQL.Binary as X

197+import Squeal.PostgreSQL.Definition as X

198+import Squeal.PostgreSQL.Definition.Function as X

199+import Squeal.PostgreSQL.Definition.Index as X

200+import Squeal.PostgreSQL.Definition.Schema as X

201+import Squeal.PostgreSQL.Definition.Table as X

202+import Squeal.PostgreSQL.Definition.Table.Constraint as X

203+import Squeal.PostgreSQL.Definition.Type as X

204+import Squeal.PostgreSQL.Definition.View as X

205+import Squeal.PostgreSQL.Expression as X

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

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

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

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

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

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

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

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

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

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

216+import Squeal.PostgreSQL.Expression.Set as X

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

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

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

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

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

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

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

224+import Squeal.PostgreSQL.List as X

225+import Squeal.PostgreSQL.Manipulation as X

226+import Squeal.PostgreSQL.Migration as X

227+import Squeal.PostgreSQL.PG as X

228+import Squeal.PostgreSQL.Pool as X

229+import Squeal.PostgreSQL.PQ as X

230+import Squeal.PostgreSQL.Query as X

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

232+import Squeal.PostgreSQL.Schema as X

233+import Squeal.PostgreSQL.Transaction as X

squeal-postgresql/src/Squeal/PostgreSQL/Alias.hsnew file+249

@@ -0,0 +1,249 @@

1+{-|

2+Module: Squeal.PostgreSQL.Alias

3+Description: Aliases

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

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+312−126

@@ -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 (DBof (Public '[])) (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 (DBof (Public '[])) (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

@@ -120,9 +120,9 @@ let

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 (DBof (Public 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 :*

@@ -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 +194,31 @@ 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+ , OidOf (..)

220+ , OidOfParam (..)

221+ , OidOfField (..)

211222 ) where

212223

213224import BinaryParser

@@ -221,6 +232,7 @@ import Data.Time

221232import Data.UUID.Types

222233import Data.Vector (Vector)

223234import Data.Word

235+import Foreign.C.Types (CUInt(CUInt))

224236import Generics.SOP

225237import Generics.SOP.Record

226238import GHC.TypeLits

@@ -234,10 +246,14 @@ import qualified Data.Text.Lazy as Lazy (Text)

234246import qualified Data.Text as Strict (Text)

235247import qualified Data.Text as Strict.Text

236248import qualified Data.Vector as Vector

249+import qualified Database.PostgreSQL.LibPQ as LibPQ

237250import qualified GHC.Generics as GHC

238251import qualified PostgreSQL.Binary.Decoding as Decoding

239252import qualified PostgreSQL.Binary.Encoding as Encoding

240253

254+import Squeal.PostgreSQL.Alias

255+import Squeal.PostgreSQL.List

256+import Squeal.PostgreSQL.PG

241257import Squeal.PostgreSQL.Schema

242258

243259-- | A `ToParam` constraint gives an encoding of a Haskell `Type` into

@@ -261,14 +277,13 @@ class ToParam (x :: Type) (pg :: PGType) where

261277 toParam :: x -> K Encoding.Encoding pg

262278instance ToParam Bool 'PGbool where toParam = K . Encoding.bool

263279instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16

264−instance ToParam Word16 'PGint2 where toParam = K . Encoding.int2_word16

265280instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32

266−instance ToParam Word32 'PGint4 where toParam = K . Encoding.int4_word32

267281instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64

268−instance ToParam Word64 'PGint8 where toParam = K . Encoding.int8_word64

282+instance ToParam Oid 'PGoid where toParam = K . Encoding.int4_word32 . getOid

269283instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4

270284instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8

271285instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric

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

272287instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid

273288instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet

274289instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8

@@ -297,16 +312,27 @@ instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where

297312instance Aeson.ToJSON x => ToParam (Jsonb x) 'PGjsonb where

298313 toParam = K . Encoding.jsonb_bytes

299314 . 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))

315+instance (ToNullityParam x ty, ty ~ nullity pg, OidOf pg)

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

317+ toParam = K

318+ . Encoding.array_foldable

319+ (getOid (oidOf @pg)) (unK . toNullityParam @x @ty)

320+ . getVarArray

321+instance (ToParam x pg, OidOf pg)

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

323+ toParam = K

324+ . Encoding.array_vector (getOid (oidOf @pg)) (unK . toParam @x @pg)

325+ . getVarArray

326+instance (ToParam x pg, OidOf pg)

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

328+ toParam = K

329+ . Encoding.nullableArray_vector

330+ (getOid (oidOf @pg)) (unK . toParam @x @pg)

331+ . getVarArray

332+instance (ToFixArray x dims ty, ty ~ nullity pg, OidOf pg)

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

334+ toParam = K . Encoding.array (getOid (oidOf @pg))

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

310336instance

311337 ( IsEnumType x

312338 , HasDatatypeInfo x

@@ -330,7 +356,7 @@ instance

330356 ( SListI fields

331357 , IsRecord x xs

332358 , AllZip ToField xs fields

333− , All HasAliasedOid fields

359+ , All OidOfField fields

334360 ) => ToParam (Composite x) ('PGcomposite fields) where

335361 toParam =

336362 let

@@ -338,7 +364,7 @@ instance

338364 encoders = htrans (Proxy @ToField) toField

339365

340366 composite

341− :: All HasAliasedOid row

367+ :: All OidOfField row

342368 => NP (K (Maybe Encoding.Encoding)) row

343369 -> K Encoding.Encoding ('PGcomposite row)

344370 composite fields = K $

@@ -355,27 +381,142 @@ instance

355381 int32BE (fromIntegral (lengthSList (Proxy @xs))) <>

356382 let

357383 each

358− :: HasAliasedOid field

384+ :: OidOfField field

359385 => K (Maybe Encoding.Encoding) field

360386 -> Encoding.Encoding

361387 each (K field :: K (Maybe Encoding.Encoding) field) =

362− word32BE (aliasedOid @field)

388+ word32BE (getOid (oidOfField @field))

363389 <> case field of

364390 Nothing -> int64BE (-1)

365391 Just value ->

366392 int32BE (fromIntegral (builderLength value))

367393 <> value

368394 in

369− hcfoldMap (Proxy @HasAliasedOid) each fields

395+ hcfoldMap (Proxy @OidOfField) each fields

370396

371397 in

372398 composite . encoders . toRecord . getComposite

373399

374−class HasAliasedOid (field :: (Symbol, NullityType)) where

375− aliasedOid :: Word32

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

377− aliasedOid = oid @ty

378−

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

401+--

402+-- >>> :set -XTypeApplications

403+-- >>> oidOf @'PGbool

404+-- Oid 16

405+class OidOf (ty :: PGType) where oidOf :: LibPQ.Oid

406+instance OidOf 'PGbool where oidOf = LibPQ.Oid 16

407+instance OidOf ('PGfixarray ns (null 'PGbool)) where oidOf = LibPQ.Oid 1000

408+instance OidOf ('PGvararray (null 'PGbool)) where oidOf = LibPQ.Oid 1000

409+instance OidOf 'PGint2 where oidOf = LibPQ.Oid 21

410+instance OidOf ('PGfixarray ns (null 'PGint2)) where oidOf = LibPQ.Oid 1005

411+instance OidOf ('PGvararray (null 'PGint2)) where oidOf = LibPQ.Oid 1005

412+instance OidOf 'PGint4 where oidOf = LibPQ.Oid 23

413+instance OidOf ('PGfixarray ns (null 'PGint4)) where oidOf = LibPQ.Oid 1007

414+instance OidOf ('PGvararray (null 'PGint4)) where oidOf = LibPQ.Oid 1007

415+instance OidOf 'PGint8 where oidOf = LibPQ.Oid 20

416+instance OidOf ('PGfixarray ns (null 'PGint8)) where oidOf = LibPQ.Oid 1016

417+instance OidOf ('PGvararray (null 'PGint8)) where oidOf = LibPQ.Oid 1016

418+instance OidOf 'PGnumeric where oidOf = LibPQ.Oid 1700

419+instance OidOf ('PGfixarray ns (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231

420+instance OidOf ('PGvararray (null 'PGnumeric)) where oidOf = LibPQ.Oid 1231

421+instance OidOf 'PGfloat4 where oidOf = LibPQ.Oid 700

422+instance OidOf ('PGfixarray ns (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021

423+instance OidOf ('PGvararray (null 'PGfloat4)) where oidOf = LibPQ.Oid 1021

424+instance OidOf 'PGfloat8 where oidOf = LibPQ.Oid 701

425+instance OidOf ('PGfixarray ns (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022

426+instance OidOf ('PGvararray (null 'PGfloat8)) where oidOf = LibPQ.Oid 1022

427+instance OidOf 'PGmoney where oidOf = LibPQ.Oid 790

428+instance OidOf ('PGfixarray ns (null 'PGmoney)) where oidOf = LibPQ.Oid 791

429+instance OidOf ('PGvararray (null 'PGmoney)) where oidOf = LibPQ.Oid 791

430+instance OidOf ('PGchar n) where oidOf = LibPQ.Oid 18

431+instance OidOf ('PGfixarray ns (null ('PGchar n))) where oidOf = LibPQ.Oid 1002

432+instance OidOf ('PGvararray (null ('PGchar n))) where oidOf = LibPQ.Oid 1002

433+instance OidOf ('PGvarchar n) where oidOf = LibPQ.Oid 1043

434+instance OidOf ('PGfixarray ns (null ('PGvarchar n))) where oidOf = LibPQ.Oid 1015

435+instance OidOf ('PGvararray (null ('PGvarchar n))) where oidOf = LibPQ.Oid 1015

436+instance OidOf 'PGtext where oidOf = LibPQ.Oid 25

437+instance OidOf ('PGfixarray ns (null 'PGtext)) where oidOf = LibPQ.Oid 1009

438+instance OidOf ('PGvararray (null 'PGtext)) where oidOf = LibPQ.Oid 1009

439+instance OidOf 'PGbytea where oidOf = LibPQ.Oid 17

440+instance OidOf ('PGfixarray ns (null 'PGbytea)) where oidOf = LibPQ.Oid 1001

441+instance OidOf ('PGvararray (null 'PGbytea)) where oidOf = LibPQ.Oid 1001

442+instance OidOf 'PGtimestamp where oidOf = LibPQ.Oid 1114

443+instance OidOf ('PGfixarray ns (null 'PGtimestamp)) where oidOf = LibPQ.Oid 1115

444+instance OidOf ('PGvararray (null 'PGtimestamp)) where oidOf = LibPQ.Oid 1115

445+instance OidOf 'PGtimestamptz where oidOf = LibPQ.Oid 1184

446+instance OidOf ('PGfixarray ns (null 'PGtimestamptz)) where oidOf = LibPQ.Oid 1185

447+instance OidOf ('PGvararray (null 'PGtimestamptz)) where oidOf = LibPQ.Oid 1185

448+instance OidOf 'PGdate where oidOf = LibPQ.Oid 1082

449+instance OidOf ('PGfixarray ns (null 'PGdate)) where oidOf = LibPQ.Oid 1182

450+instance OidOf ('PGvararray (null 'PGdate)) where oidOf = LibPQ.Oid 1182

451+instance OidOf 'PGtime where oidOf = LibPQ.Oid 1083

452+instance OidOf ('PGfixarray ns (null 'PGtime)) where oidOf = LibPQ.Oid 1183

453+instance OidOf ('PGvararray (null 'PGtime)) where oidOf = LibPQ.Oid 1183

454+instance OidOf 'PGtimetz where oidOf = LibPQ.Oid 1266

455+instance OidOf ('PGfixarray ns (null 'PGtimetz)) where oidOf = LibPQ.Oid 1270

456+instance OidOf ('PGvararray (null 'PGtimetz)) where oidOf = LibPQ.Oid 1270

457+instance OidOf 'PGinterval where oidOf = LibPQ.Oid 1186

458+instance OidOf ('PGfixarray ns (null 'PGinterval)) where oidOf = LibPQ.Oid 1187

459+instance OidOf ('PGvararray (null 'PGinterval)) where oidOf = LibPQ.Oid 1187

460+instance OidOf 'PGuuid where oidOf = LibPQ.Oid 2950

461+instance OidOf ('PGfixarray ns (null 'PGuuid)) where oidOf = LibPQ.Oid 2951

462+instance OidOf ('PGvararray (null 'PGuuid)) where oidOf = LibPQ.Oid 2951

463+instance OidOf 'PGinet where oidOf = LibPQ.Oid 869

464+instance OidOf ('PGfixarray ns (null 'PGinet)) where oidOf = LibPQ.Oid 1041

465+instance OidOf ('PGvararray (null 'PGinet)) where oidOf = LibPQ.Oid 1041

466+instance OidOf 'PGjson where oidOf = LibPQ.Oid 114

467+instance OidOf ('PGfixarray ns (null 'PGjson)) where oidOf = LibPQ.Oid 199

468+instance OidOf ('PGvararray (null 'PGjson)) where oidOf = LibPQ.Oid 199

469+instance OidOf 'PGjsonb where oidOf = LibPQ.Oid 3802

470+instance OidOf ('PGfixarray ns (null 'PGjsonb)) where oidOf = LibPQ.Oid 3807

471+instance OidOf ('PGvararray (null 'PGjsonb)) where oidOf = LibPQ.Oid 3807

472+instance OidOf 'PGtsvector where oidOf = LibPQ.Oid 3614

473+instance OidOf ('PGfixarray ns (null 'PGtsvector)) where oidOf = LibPQ.Oid 3643

474+instance OidOf ('PGvararray (null 'PGtsvector)) where oidOf = LibPQ.Oid 3643

475+instance OidOf 'PGtsquery where oidOf = LibPQ.Oid 3615

476+instance OidOf ('PGfixarray ns (null 'PGtsquery)) where oidOf = LibPQ.Oid 3645

477+instance OidOf ('PGvararray (null 'PGtsquery)) where oidOf = LibPQ.Oid 3645

478+instance OidOf 'PGoid where oidOf = LibPQ.Oid 26

479+instance OidOf ('PGfixarray ns (null 'PGoid)) where oidOf = LibPQ.Oid 1028

480+instance OidOf ('PGvararray (null 'PGoid)) where oidOf = LibPQ.Oid 1028

481+instance OidOf ('PGrange 'PGint4) where oidOf = LibPQ.Oid 3904

482+instance OidOf ('PGfixarray ns (null ('PGrange 'PGint4))) where oidOf = LibPQ.Oid 3905

483+instance OidOf ('PGvararray (null ('PGrange 'PGint4))) where oidOf = LibPQ.Oid 3905

484+instance OidOf ('PGrange 'PGint8) where oidOf = LibPQ.Oid 3926

485+instance OidOf ('PGfixarray ns (null ('PGrange 'PGint8))) where oidOf = LibPQ.Oid 3927

486+instance OidOf ('PGvararray (null ('PGrange 'PGint8))) where oidOf = LibPQ.Oid 3927

487+instance OidOf ('PGrange 'PGnumeric) where oidOf = LibPQ.Oid 3906

488+instance OidOf ('PGfixarray ns (null ('PGrange 'PGnumeric))) where oidOf = LibPQ.Oid 3907

489+instance OidOf ('PGvararray (null ('PGrange 'PGnumeric))) where oidOf = LibPQ.Oid 3907

490+instance OidOf ('PGrange 'PGtimestamp) where oidOf = LibPQ.Oid 3908

491+instance OidOf ('PGfixarray ns (null ('PGrange 'PGtimestamp))) where oidOf = LibPQ.Oid 3909

492+instance OidOf ('PGvararray (null ('PGrange 'PGtimestamp))) where oidOf = LibPQ.Oid 3909

493+instance OidOf ('PGrange 'PGtimestamptz) where oidOf = LibPQ.Oid 3910

494+instance OidOf ('PGfixarray ns (null ('PGrange 'PGtimestamptz))) where oidOf = LibPQ.Oid 3911

495+instance OidOf ('PGvararray (null ('PGrange 'PGtimestamptz))) where oidOf = LibPQ.Oid 3911

496+instance OidOf ('PGrange 'PGdate) where oidOf = LibPQ.Oid 3912

497+instance OidOf ('PGfixarray ns (null ('PGrange 'PGdate))) where oidOf = LibPQ.Oid 3913

498+instance OidOf ('PGvararray (null ('PGrange 'PGdate))) where oidOf = LibPQ.Oid 3913

499+instance {-# OVERLAPPABLE #-} OidOf ('PGrange ty) where oidOf = LibPQ.invalidOid

500+instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGrange ty))) where oidOf = LibPQ.invalidOid

501+instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGrange ty))) where oidOf = LibPQ.invalidOid

502+instance {-# OVERLAPPABLE #-} OidOf ('PGcomposite row) where oidOf = LibPQ.invalidOid

503+instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGcomposite row))) where oidOf = LibPQ.invalidOid

504+instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGcomposite row))) where oidOf = LibPQ.invalidOid

505+instance {-# OVERLAPPABLE #-} OidOf ('PGenum labels) where oidOf = LibPQ.invalidOid

506+instance {-# OVERLAPPABLE #-} OidOf ('PGfixarray ns (null ('PGenum labels))) where oidOf = LibPQ.invalidOid

507+instance {-# OVERLAPPABLE #-} OidOf ('PGvararray (null ('PGenum labels))) where oidOf = LibPQ.invalidOid

508+

509+class OidOfParam (ty :: NullityType) where oidOfParam :: Oid

510+instance OidOf ty => OidOfParam (null ty) where oidOfParam = oidOf @ty

511+

512+-- | Lifts a `OidOf` constraint to a field.

513+class OidOfField (field :: (Symbol, NullityType)) where

514+ oidOfField :: Oid

515+instance OidOf ty => OidOfField (alias ::: nullity ty) where

516+ oidOfField = oidOf @ty

517+

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

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

379520class ToNullityParam (x :: Type) (ty :: NullityType) where

380521 toNullityParam :: x -> K (Maybe Encoding.Encoding) ty

381522instance ToParam x pg => ToNullityParam x ('NotNull pg) where

@@ -383,55 +524,36 @@ instance ToParam x pg => ToNullityParam x ('NotNull pg) where

383524instance ToParam x pg => ToNullityParam (Maybe x) ('Null pg) where

384525 toNullityParam = K . fmap (unK . toParam @x @pg)

385526

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

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

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

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

386531class ToField (x :: (Symbol, Type)) (field :: (Symbol, NullityType)) where

387532 toField :: P x -> K (Maybe Encoding.Encoding) field

388533instance ToNullityParam x ty => ToField (alias ::: x) (alias ::: ty) where

389534 toField (P x) = K . unK $ toNullityParam @x @ty x

390535

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 #-}

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

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

538+-- You should not define instances for

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

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

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

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

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

544+ . toNullityParam @x @ty

545+instance

423546 ( IsProductType product xs

424− , Length xs ~ n

547+ , Length xs ~ dim

425548 , 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

549+ , ToFixArray x dims ty )

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

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

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

431553

432554-- | A `ToParams` constraint generically sequences the encodings of `Type`s

433555-- 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

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

435557-- which in turn provide `ToParams` instances.

436558class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where

437559 -- | >>> type Params = '[ 'NotNull 'PGbool, 'Null 'PGint2]

@@ -460,9 +582,11 @@ instance FromValue 'PGbool Bool where fromValue = Decoding.bool

460582instance FromValue 'PGint2 Int16 where fromValue = Decoding.int

461583instance FromValue 'PGint4 Int32 where fromValue = Decoding.int

462584instance FromValue 'PGint8 Int64 where fromValue = Decoding.int

585+instance FromValue 'PGoid Word32 where fromValue = Decoding.int

463586instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4

464587instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8

465588instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric

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

466590instance FromValue 'PGuuid UUID where fromValue = Decoding.uuid

467591instance FromValue 'PGinet (NetAddr IP) where fromValue = Decoding.inet

468592instance FromValue ('PGchar 1) Char where fromValue = Decoding.char

@@ -492,12 +616,41 @@ instance Aeson.FromJSON x => FromValue 'PGjson (Json x) where

492616instance Aeson.FromJSON x => FromValue 'PGjsonb (Jsonb x) where

493617 fromValue = Jsonb <$>

494618 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)

619+instance FromValue pg y

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

621+ fromValue =

622+ let

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

624+ in

625+ Decoding.array $ Decoding.dimensionArray rep

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

627+instance FromValue pg y

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

629+ fromValue =

630+ let

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

632+ in

633+ Decoding.array $ Decoding.dimensionArray rep

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

635+instance FromValue pg y

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

637+ fromValue =

638+ let

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

640+ in

641+ Decoding.array $ Decoding.dimensionArray rep

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

643+instance FromValue pg y

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

645+ fromValue =

646+ let

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

648+ in

649+ Decoding.array $ Decoding.dimensionArray rep

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

651+instance FromFixArray dims ty y

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

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

501654instance

502655 ( IsEnumType y

503656 , HasDatatypeInfo y

@@ -568,49 +721,32 @@ instance FromValue pg y

568721 K (Just bytestring) -> P . Just <$>

569722 Decoding.valueParser (fromValue @pg) bytestring

570723

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

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

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

726+-- You should not define instances for

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

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

729+ fromFixArray :: Decoding.Array y

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

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

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

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

734+instance

735+ ( IsProductType product ys

736+ , Length ys ~ dim

600737 , All ((~) y) ys

601− , SListI ys

602− , IsProductType product ys )

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

604− fromArray =

738+ , FromFixArray dims ty y )

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

740+ fromFixArray =

605741 let

606742 rep _ = fmap (to . SOP . Z) . replicateMN

607743 in

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

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

609745

610746-- | A `FromRow` constraint generically sequences the parsings of the columns

611747-- of a `RowType` into the fields of a record `Type` provided they have

612748-- the same field names. You should not define instances of `FromRow`.

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

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

614750-- provide `FromRow` instances.

615751class SListI result => FromRow (result :: RowType) y where

616752 -- | >>> :set -XOverloadedStrings

@@ -633,6 +769,53 @@ instance

633769 = fmap fromRecord

634770 . hsequence'

635771 . htrans (Proxy @FromField) fromField

772+------------------------------------------------------

773+-- P records

774+------------------------------------------------------

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

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

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

778+-- instance

779+-- ( row ~ Join row1 row2

780+-- , FromRow row1 hask1

781+-- , FromRow row2 hask2

782+-- , SListI row

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

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

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

786+-- instance

787+-- ( row ~ Join row1 row23

788+-- , FromRow row1 hask1

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

790+-- , SListI row

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

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

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

794+-- hask1 <- fromRow row1

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

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

797+-- instance

798+-- ( row ~ Join row1 row234

799+-- , FromRow row1 hask1

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

801+-- , SListI row

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

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

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

805+-- hask1 <- fromRow row1

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

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

808+-- instance

809+-- ( row ~ Join row1 row2345

810+-- , FromRow row1 hask1

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

812+-- , SListI row

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

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

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

816+-- hask1 <- fromRow row1

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

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

636819

637820-- | `Only` is a 1-tuple type, useful for encoding a single parameter with

638821-- `toParams` or decoding a single value with `fromRow`.

@@ -659,4 +842,7 @@ replicateMN

659842 :: forall x xs m. (All ((~) x) xs, Monad m, SListI xs)

660843 => m x -> m (NP I xs)

661844replicateMN mx = hsequence' $

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

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

846+

847+getOid :: LibPQ.Oid -> Word32

848+getOid (LibPQ.Oid (CUInt oid)) = oid

squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+17−968

@@ -11,13 +11,15 @@ Squeal data definition language.

1111{-# LANGUAGE

1212 AllowAmbiguousTypes

1313 , ConstraintKinds

14+ , DeriveAnyClass

1415 , DeriveGeneric

16+ , DerivingStrategies

1517 , FlexibleContexts

1618 , FlexibleInstances

1719 , GADTs

18− , GeneralizedNewtypeDeriving

1920 , LambdaCase

2021 , MultiParamTypeClasses

22+ , OverloadedLabels

2123 , OverloadedStrings

2224 , RankNTypes

2325 , ScopedTypeVariables

@@ -25,83 +27,31 @@ Squeal data definition language.

2527 , TypeInType

2628 , TypeOperators

2729 , UndecidableSuperClasses

30+ , UndecidableInstances

2831#-}

2932

3033module Squeal.PostgreSQL.Definition

3134 ( -- * Definition

32− Definition (UnsafeDefinition, renderDefinition)

35+ Definition (..)

3336 , (>>>)

34− -- * Tables

35− -- ** Create

36− , createSchema

37− , createSchemaIfNotExists

38− , createTable

39− , createTableIfNotExists

40− , TableConstraintExpression (..)

41− , check

42− , unique

43− , primaryKey

44− , foreignKey

45− , ForeignKeyed

46− , OnDeleteClause (OnDeleteNoAction, OnDeleteRestrict, OnDeleteCascade)

47− , renderOnDeleteClause

48− , OnUpdateClause (OnUpdateNoAction, OnUpdateRestrict, OnUpdateCascade)

49− , renderOnUpdateClause

50− -- ** Drop

51− , dropTable

52− -- ** Alter

53− , alterTable

54− , alterTableRename

55− , AlterTable (UnsafeAlterTable, renderAlterTable)

56− , addConstraint

57− , dropConstraint

58− , AddColumn (addColumn)

59− , dropColumn

60− , renameColumn

61− , alterColumn

62− , AlterColumn (UnsafeAlterColumn, renderAlterColumn)

63− , setDefault

64− , dropDefault

65− , setNotNull

66− , dropNotNull

67− , alterType

68− -- * Views

69− , createView

70− , dropView

71− -- * Types

72− , createTypeEnum

73− , createTypeEnumFrom

74− , createTypeComposite

75− , createTypeCompositeFrom

76− , dropType

77− -- * Columns

78− , ColumnTypeExpression (..)

79− , nullable

80− , notNullable

81− , default_

82− , serial2

83− , smallserial

84− , serial4

85− , serial

86− , serial8

87− , bigserial

37+ , manipDefinition

8838 ) where

8939

9040import Control.Category

9141import Control.DeepSeq

9242import Data.ByteString

9343import Data.Monoid

94−import GHC.TypeLits

9544import Prelude hiding ((.), id)

9645

97−import qualified Generics.SOP as SOP

9846import qualified GHC.Generics as GHC

9947

100−import Squeal.PostgreSQL.Expression

101−import Squeal.PostgreSQL.Query

48+import Squeal.PostgreSQL.Manipulation

10249import Squeal.PostgreSQL.Render

10350import Squeal.PostgreSQL.Schema

10451

52+-- $setup

53+-- >>> import Squeal.PostgreSQL

54+

10555{-----------------------------------------

10656statements

10757-----------------------------------------}

@@ -121,913 +71,12 @@ instance RenderSQL (Definition schemas0 schemas1) where

12171instance Category Definition where

12272 id = UnsafeDefinition ";"

12373 ddl1 . ddl0 = UnsafeDefinition $

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

125−

126−{-----------------------------------------

127−CREATE statements

128−-----------------------------------------}

129−

130−createSchema

131− :: KnownSymbol sch

132− => Alias sch

133− -> Definition schemas (Create sch '[] schemas)

134−createSchema sch = UnsafeDefinition $

135− "CREATE" <+> "SCHEMA" <+> renderAlias sch <> ";"

136−

137−createSchemaIfNotExists

138− :: (KnownSymbol sch, Has sch schemas schema)

139− => Alias sch

140− -> Definition schemas schemas

141−createSchemaIfNotExists sch = UnsafeDefinition $

142− "CREATE" <+> "SCHEMA" <+> "IF" <+> "NOT" <+> "EXISTS"

143− <+> renderAlias sch <> ";"

144−

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

146−

147−>>> :set -XOverloadedLabels

148−>>> :{

149−type Table = '[] :=>

150− '[ "a" ::: 'NoDef :=> 'Null 'PGint4

151− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

152−:}

153−

154−>>> :{

155−let

156− setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table])

157− setup = createTable #tab

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

159−in printSQL setup

160−:}

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

162−-}

163−createTable

164− :: ( KnownSymbol sch

165− , KnownSymbol tab

166− , columns ~ (col ': cols)

167− , SOP.SListI columns

168− , SOP.SListI constraints

169− , Has sch schemas0 schema0

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

171− => QualifiedAlias sch tab -- ^ the name of the table to add

172− -> NP (Aliased (ColumnTypeExpression schemas0)) columns

173− -- ^ the names and datatype of each column

174− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints

175− -- ^ constraints that must hold for the table

176− -> Definition schemas0 schemas1

177−createTable tab columns constraints = UnsafeDefinition $

178− "CREATE TABLE" <+> renderCreation tab columns constraints

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

17975

180−{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.

181−Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.

182−`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in

183−the `Category` of `Definition`s.

184−

185−>>> :set -XOverloadedLabels -XTypeApplications

186−>>> :{

187−type Table = '[] :=>

188− '[ "a" ::: 'NoDef :=> 'Null 'PGint4

189− , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

190−:}

191−

192−>>> type Schemas = Public '["tab" ::: 'Table Table]

193−

194−>>> :{

195−let

196− setup :: Definition Schemas Schemas

197− setup = createTableIfNotExists #tab

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

199−in printSQL setup

200−:}

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

202−-}

203−createTableIfNotExists

204− :: ( Has sch schemas schema

205− , Has tab schema ('Table (constraints :=> columns))

206− , SOP.SListI columns

207− , SOP.SListI constraints )

208− => QualifiedAlias sch tab -- ^ the name of the table to add

209− -> NP (Aliased (ColumnTypeExpression schemas)) columns

210− -- ^ the names and datatype of each column

211− -> NP (Aliased (TableConstraintExpression sch tab schemas)) constraints

212− -- ^ constraints that must hold for the table

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

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

78+manipDefinition

79+ :: Manipulation '[] schemas '[] '[]

80+ -- ^ no input or output

21381 -> Definition schemas schemas

214−createTableIfNotExists tab columns constraints = UnsafeDefinition $

215− "CREATE TABLE IF NOT EXISTS"

216− <+> renderCreation tab columns constraints

217−

218−-- helper function for `createTable` and `createTableIfNotExists`

219−renderCreation

220− :: ( KnownSymbol sch

221− , KnownSymbol tab

222− , SOP.SListI columns

223− , SOP.SListI constraints )

224− => QualifiedAlias sch tab -- ^ the name of the table to add

225− -> NP (Aliased (ColumnTypeExpression schemas0)) columns

226− -- ^ the names and datatype of each column

227− -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints

228− -- ^ constraints that must hold for the table

229− -> ByteString

230−renderCreation tab columns constraints = renderQualifiedAlias tab

231− <+> parenthesized

232− ( renderCommaSeparated renderColumnDef columns

233− <> ( case constraints of

234− Nil -> ""

235− _ -> ", " <>

236− renderCommaSeparated renderConstraint constraints ) )

237− <> ";"

238− where

239− renderColumnDef :: Aliased (ColumnTypeExpression schemas) x -> ByteString

240− renderColumnDef (ty `As` column) =

241− renderAlias column <+> renderColumnTypeExpression ty

242− renderConstraint

243− :: Aliased (TableConstraintExpression sch tab schemas) constraint

244− -> ByteString

245− renderConstraint (constraint `As` alias) =

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

247−

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

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

250−-- too coarse. For example, a column containing a product price should

251−-- probably only accept positive values. But there is no standard data type

252−-- that accepts only positive numbers. Another issue is that you might want

253−-- to constrain column data with respect to other columns or rows.

254−-- For example, in a table containing product information,

255−-- there should be only one row for each product number.

256−-- `TableConstraint`s give you as much control over the data in your tables

257−-- as you wish. If a user attempts to store data in a column that would

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

259−-- even if the value came from the default value definition.

260−newtype TableConstraintExpression

261− (sch :: Symbol)

262− (tab :: Symbol)

263− (schemas :: SchemasType)

264− (constraint :: TableConstraint)

265− = UnsafeTableConstraintExpression

266− { renderTableConstraintExpression :: ByteString }

267− deriving (GHC.Generic,Show,Eq,Ord,NFData)

268−

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

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

271−a Boolean (truth-value) expression.

272−

273−>>> :{

274−type Schema = '[

275− "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[

276− "a" ::: 'NoDef :=> 'NotNull 'PGint4,

277− "b" ::: 'NoDef :=> 'NotNull 'PGint4

278− ])]

279−:}

280−

281−>>> :{

282−let

283− definition :: Definition (Public '[]) (Public Schema)

284− definition = createTable #tab

285− ( (int & notNullable) `as` #a :*

286− (int & notNullable) `as` #b )

287− ( check (#a :* #b) (#a .> #b) `as` #inequality )

288−:}

289−

290−>>> printSQL definition

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

292−-}

293−check

294− :: ( Has sch schemas schema

295− , Has tab schema ('Table table)

296− , HasAll aliases (TableToRow table) subcolumns )

297− => NP Alias aliases

298− -- ^ specify the subcolumns which are getting checked

299− -> (forall t. Condition ('[] :=> schemas) '[t ::: subcolumns] 'Ungrouped '[])

300− -- ^ a closed `Condition` on those subcolumns

301− -> TableConstraintExpression sch tab schemas ('Check aliases)

302−check _cols condition = UnsafeTableConstraintExpression $

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

304−

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

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

307−

308−>>> :{

309−type Schema = '[

310− "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[

311− "a" ::: 'NoDef :=> 'Null 'PGint4,

312− "b" ::: 'NoDef :=> 'Null 'PGint4

313− ])]

314−:}

315−

316−>>> :{

317−let

318− definition :: Definition (Public '[]) (Public Schema)

319− definition = createTable #tab

320− ( (int & nullable) `as` #a :*

321− (int & nullable) `as` #b )

322− ( unique (#a :* #b) `as` #uq_a_b )

323−:}

324−

325−>>> printSQL definition

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

327−-}

328−unique

329− :: ( Has sch schemas schema

330− , Has tab schema('Table table)

331− , HasAll aliases (TableToRow table) subcolumns )

332− => NP Alias aliases

333− -- ^ specify subcolumns which together are unique for each row

334− -> TableConstraintExpression sch tab schemas ('Unique aliases)

335−unique columns = UnsafeTableConstraintExpression $

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

337−

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

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

340−This requires that the values be both unique and not null.

341−

342−>>> :{

343−type Schema = '[

344− "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[

345− "id" ::: 'Def :=> 'NotNull 'PGint4,

346− "name" ::: 'NoDef :=> 'NotNull 'PGtext

347− ])]

348−:}

349−

350−>>> :{

351−let

352− definition :: Definition (Public '[]) (Public Schema)

353− definition = createTable #tab

354− ( serial `as` #id :*

355− (text & notNullable) `as` #name )

356− ( primaryKey #id `as` #pk_id )

357−:}

358−

359−>>> printSQL definition

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

361−-}

362−primaryKey

363− :: ( Has sch schemas schema

364− , Has tab schema ('Table table)

365− , HasAll aliases (TableToColumns table) subcolumns

366− , AllNotNull subcolumns )

367− => NP Alias aliases

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

369− -> TableConstraintExpression sch tab schemas ('PrimaryKey aliases)

370−primaryKey columns = UnsafeTableConstraintExpression $

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

372−

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

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

375−another table. We say this maintains the referential integrity

376−between two related tables.

377−

378−>>> :{

379−type Schema =

380− '[ "users" ::: 'Table (

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

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

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

384− ])

385− , "emails" ::: 'Table (

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

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

388− ] :=>

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

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

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

392− ])

393− ]

394−:}

395−

396−>>> :{

397−let

398− setup :: Definition (Public '[]) (Public Schema)

399− setup =

400− createTable #users

401− ( serial `as` #id :*

402− (text & notNullable) `as` #name )

403− ( primaryKey #id `as` #pk_users ) >>>

404− createTable #emails

405− ( serial `as` #id :*

406− (int & notNullable) `as` #user_id :*

407− (text & nullable) `as` #email )

408− ( primaryKey #id `as` #pk_emails :*

409− foreignKey #user_id #users #id

410− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

411−in printSQL setup

412−:}

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

414−CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);

415−

416−A `foreignKey` can even be a table self-reference.

417−

418−>>> :{

419−type Schema =

420− '[ "employees" ::: 'Table (

421− '[ "employees_pk" ::: 'PrimaryKey '["id"]

422− , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]

423− ] :=>

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

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

426− , "employer_id" ::: 'NoDef :=> 'Null 'PGint4

427− ])

428− ]

429−:}

430−

431−>>> :{

432−let

433− setup :: Definition (Public '[]) (Public Schema)

434− setup =

435− createTable #employees

436− ( serial `as` #id :*

437− (text & notNullable) `as` #name :*

438− (integer & nullable) `as` #employer_id )

439− ( primaryKey #id `as` #employees_pk :*

440− foreignKey #employer_id #employees #id

441− OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )

442−in printSQL setup

443−:}

444−CREATE TABLE "employees" ("id" serial, "name" text NOT NULL, "employer_id" integer NULL, CONSTRAINT "employees_pk" PRIMARY KEY ("id"), CONSTRAINT "employees_employer_fk" FOREIGN KEY ("employer_id") REFERENCES "employees" ("id") ON DELETE CASCADE ON UPDATE CASCADE);

445−-}

446−foreignKey

447− :: (ForeignKeyed schemas sch schema child parent

448− table reftable

449− columns refcolumns

450− constraints cols

451− reftys tys )

452− => NP Alias columns

453− -- ^ column or columns in the table

454− -> Alias parent

455− -- ^ reference table

456− -> NP Alias refcolumns

457− -- ^ reference column or columns in the reference table

458− -> OnDeleteClause

459− -- ^ what to do when reference is deleted

460− -> OnUpdateClause

461− -- ^ what to do when reference is updated

462− -> TableConstraintExpression sch child schemas

463− ('ForeignKey columns parent refcolumns)

464−foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $

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

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

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

468− <+> renderOnDeleteClause ondel

469− <+> renderOnUpdateClause onupd

470−

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

472−type ForeignKeyed schemas

473− sch

474− schema

475− child parent

476− table reftable

477− columns refcolumns

478− constraints cols

479− reftys tys =

480− ( Has sch schemas schema

481− , Has child schema ('Table table)

482− , Has parent schema ('Table reftable)

483− , HasAll columns (TableToColumns table) tys

484− , reftable ~ (constraints :=> cols)

485− , HasAll refcolumns cols reftys

486− , SOP.AllZip SamePGType tys reftys

487− , Uniquely refcolumns constraints )

488−

489−-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.

490−data OnDeleteClause

491− = OnDeleteNoAction

492− -- ^ if any referencing rows still exist when the constraint is checked,

493− -- an error is raised

494− | OnDeleteRestrict -- ^ prevents deletion of a referenced row

495− | OnDeleteCascade

496− -- ^ specifies that when a referenced row is deleted,

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

498− deriving (GHC.Generic,Show,Eq,Ord)

499−instance NFData OnDeleteClause

500−

501−-- | Render `OnDeleteClause`.

502−renderOnDeleteClause :: OnDeleteClause -> ByteString

503−renderOnDeleteClause = \case

504− OnDeleteNoAction -> "ON DELETE NO ACTION"

505− OnDeleteRestrict -> "ON DELETE RESTRICT"

506− OnDeleteCascade -> "ON DELETE CASCADE"

507−

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

509−-- when a referenced column is changed (updated).

510−data OnUpdateClause

511− = OnUpdateNoAction

512− -- ^ if any referencing rows has not changed when the constraint is checked,

513− -- an error is raised

514− | OnUpdateRestrict -- ^ prevents update of a referenced row

515− | OnUpdateCascade

516− -- ^ the updated values of the referenced column(s) should be copied

517− -- into the referencing row(s)

518− deriving (GHC.Generic,Show,Eq,Ord)

519−instance NFData OnUpdateClause

520−

521−-- | Render `OnUpdateClause`.

522−renderOnUpdateClause :: OnUpdateClause -> ByteString

523−renderOnUpdateClause = \case

524− OnUpdateNoAction -> "ON UPDATE NO ACTION"

525− OnUpdateRestrict -> "ON UPDATE RESTRICT"

526− OnUpdateCascade -> "ON UPDATE CASCADE"

527−

528−{-----------------------------------------

529−DROP statements

530−-----------------------------------------}

531−

532−-- | `dropTable` removes a table from the schema.

533−--

534−-- >>> :{

535−-- let

536−-- definition :: Definition '["public" ::: '["muh_table" ::: 'Table t]] (Public '[])

537−-- definition = dropTable #muh_table

538−-- :}

539−--

540−-- >>> printSQL definition

541−-- DROP TABLE "muh_table";

542−dropTable

543− :: ( Has sch schemas schema

544− , Has tab schema ('Table table))

545− => QualifiedAlias sch tab -- ^ table to remove

546− -> Definition schemas (Alter sch (Drop tab schema) schemas)

547−dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderQualifiedAlias tab <> ";"

548−

549−{-----------------------------------------

550−ALTER statements

551−-----------------------------------------}

552−

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

554−alterTable

555− :: (Has sch schemas schema, Has tab schema ('Table table0))

556− => QualifiedAlias sch tab -- ^ table to alter

557− -> AlterTable sch tab schemas table1 -- ^ alteration to perform

558− -> Definition schemas (Alter sch (Alter tab ('Table table1) schema) schemas)

559−alterTable tab alteration = UnsafeDefinition $

560− "ALTER TABLE"

561− <+> renderQualifiedAlias tab

562− <+> renderAlterTable alteration

563− <> ";"

564−

565−-- | `alterTableRename` changes the name of a table from the schema.

566−--

567−-- >>> printSQL $ alterTableRename #foo #bar

568−-- ALTER TABLE "foo" RENAME TO "bar";

569−alterTableRename

570− :: (KnownSymbol table0, KnownSymbol table1)

571− => Alias table0 -- ^ table to rename

572− -> Alias table1 -- ^ what to rename it

573− -> Definition schema (Rename table0 table1 schema)

574−alterTableRename table0 table1 = UnsafeDefinition $

575− "ALTER TABLE" <+> renderAlias table0

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

577−

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

579−-- of a table.

580−newtype AlterTable

581− (sch :: Symbol)

582− (tab :: Symbol)

583− (schemas :: SchemasType)

584− (table :: TableType) =

585− UnsafeAlterTable {renderAlterTable :: ByteString}

586− deriving (GHC.Generic,Show,Eq,Ord,NFData)

587−

588−-- | An `addConstraint` adds a table constraint.

589−--

590−-- >>> :{

591−-- let

592−-- definition :: Definition

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

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

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

596−-- in printSQL definition

597−-- :}

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

599−addConstraint

600− :: ( KnownSymbol alias

601− , Has sch schemas schema

602− , Has tab schema ('Table table0)

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

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

605− => Alias alias

606− -> TableConstraintExpression sch tab schemas constraint

607− -- ^ constraint to add

608− -> AlterTable sch tab schemas table1

609−addConstraint alias constraint = UnsafeAlterTable $

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

611− <+> renderTableConstraintExpression constraint

612−

613−-- | A `dropConstraint` drops a table constraint.

614−--

615−-- >>> :{

616−-- let

617−-- definition :: Definition

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

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

620−-- definition = alterTable #tab (dropConstraint #positive)

621−-- in printSQL definition

622−-- :}

623−-- ALTER TABLE "tab" DROP CONSTRAINT "positive";

624−dropConstraint

625− :: ( KnownSymbol constraint

626− , Has sch schemas schema

627− , Has tab schema ('Table table0)

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

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

630− => Alias constraint

631− -- ^ constraint to drop

632− -> AlterTable sch tab schemas table1

633−dropConstraint constraint = UnsafeAlterTable $

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

635−

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

637−class AddColumn ty where

638− -- | `addColumn` adds a new column, initially filled with whatever

639− -- default value is given or with @NULL@.

640− --

641− -- >>> :{

642− -- let

643− -- definition :: Definition

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

645− -- '["public" ::: '["tab" ::: 'Table ('[] :=>

646− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

649− -- in printSQL definition

650− -- :}

651− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';

652− --

653− -- >>> :{

654− -- let

655− -- definition :: Definition

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

657− -- '["public" ::: '["tab" ::: 'Table ('[] :=>

658− -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

661− -- in printSQL definition

662− -- :}

663− -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;

664− addColumn

665− :: ( KnownSymbol column

666− , Has sch schemas schema

667− , Has tab schema ('Table table0)

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

669− => Alias column -- ^ column to add

670− -> ColumnTypeExpression schemas ty -- ^ type of the new column

671− -> AlterTable sch tab schemas (constraints :=> Create column ty columns)

672− addColumn column ty = UnsafeAlterTable $

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

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

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

676−

677−-- | A `dropColumn` removes a column. Whatever data was in the column

678−-- disappears. Table constraints involving the column are dropped, too.

679−-- However, if the column is referenced by a foreign key constraint of

680−-- another table, PostgreSQL will not silently drop that constraint.

681−--

682−-- >>> :{

683−-- let

684−-- definition :: Definition

685−-- '["public" ::: '["tab" ::: 'Table ('[] :=>

686−-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

689−-- definition = alterTable #tab (dropColumn #col2)

690−-- in printSQL definition

691−-- :}

692−-- ALTER TABLE "tab" DROP COLUMN "col2";

693−dropColumn

694− :: ( KnownSymbol column

695− , Has sch schemas schema

696− , Has tab schema ('Table table0)

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

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

699− => Alias column -- ^ column to remove

700− -> AlterTable sch tab schemas table1

701−dropColumn column = UnsafeAlterTable $

702− "DROP COLUMN" <+> renderAlias column

703−

704−-- | A `renameColumn` renames a column.

705−--

706−-- >>> :{

707−-- let

708−-- definition :: Definition

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

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

711−-- definition = alterTable #tab (renameColumn #foo #bar)

712−-- in printSQL definition

713−-- :}

714−-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";

715−renameColumn

716− :: ( KnownSymbol column0

717− , KnownSymbol column1

718− , Has sch schemas schema

719− , Has tab schema ('Table table0)

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

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

722− => Alias column0 -- ^ column to rename

723− -> Alias column1 -- ^ what to rename the column

724− -> AlterTable sch tab schemas table1

725−renameColumn column0 column1 = UnsafeAlterTable $

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

727−

728−-- | An `alterColumn` alters a single column.

729−alterColumn

730− :: ( KnownSymbol column

731− , Has sch schemas schema

732− , Has tab schema ('Table table0)

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

734− , Has column columns ty0

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

736− => Alias column -- ^ column to alter

737− -> AlterColumn schemas ty0 ty1 -- ^ alteration to perform

738− -> AlterTable sch tab schemas table1

739−alterColumn column alteration = UnsafeAlterTable $

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

741−

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

743−newtype AlterColumn (schemas :: SchemasType) (ty0 :: ColumnType) (ty1 :: ColumnType) =

744− UnsafeAlterColumn {renderAlterColumn :: ByteString}

745− deriving (GHC.Generic,Show,Eq,Ord,NFData)

746−

747−-- | A `setDefault` sets a new default for a column. Note that this doesn't

748−-- affect any existing rows in the table, it just changes the default for

749−-- future insert and update commands.

750−--

751−-- >>> :{

752−-- let

753−-- definition :: Definition

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

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

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

757−-- in printSQL definition

758−-- :}

759−-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;

760−setDefault

761− :: Expression ('[] :=> schemas) '[] 'Ungrouped '[] ty -- ^ default value to set

762− -> AlterColumn schemas (constraint :=> ty) ('Def :=> ty)

763−setDefault expression = UnsafeAlterColumn $

764− "SET DEFAULT" <+> renderExpression expression

765−

766−-- | A `dropDefault` removes any default value for a column.

767−--

768−-- >>> :{

769−-- let

770−-- definition :: Definition

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

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

773−-- definition = alterTable #tab (alterColumn #col dropDefault)

774−-- in printSQL definition

775−-- :}

776−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;

777−dropDefault :: AlterColumn schemas ('Def :=> ty) ('NoDef :=> ty)

778−dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

779−

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

781−-- The constraint will be checked immediately, so the table data must satisfy

782−-- the constraint before it can be added.

783−--

784−-- >>> :{

785−-- let

786−-- definition :: Definition

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

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

789−-- definition = alterTable #tab (alterColumn #col setNotNull)

790−-- in printSQL definition

791−-- :}

792−-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;

793−setNotNull

794− :: AlterColumn schemas (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)

795−setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

796−

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

798−--

799−-- >>> :{

800−-- let

801−-- definition :: Definition

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

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

804−-- definition = alterTable #tab (alterColumn #col dropNotNull)

805−-- in printSQL definition

806−-- :}

807−-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;

808−dropNotNull

809− :: AlterColumn schemas (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)

810−dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

811−

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

813−-- This will succeed only if each existing entry in the column can be

814−-- converted to the new type by an implicit cast.

815−--

816−-- >>> :{

817−-- let

818−-- definition :: Definition

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

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

821−-- definition =

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

823−-- in printSQL definition

824−-- :}

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

826−alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty

827−alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty

828−

829−{- | Create a view.

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

831−>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]

832−>>> :{

833−let

834− definition :: Definition

835− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]

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

837− definition =

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

839−in printSQL definition

840−:}

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

842−-}

843−createView

844− :: (KnownSymbol sch, KnownSymbol vw, Has sch schemas schema)

845− => QualifiedAlias sch vw -- ^ the name of the view to add

846− -> Query ('[] :=> schemas) '[] view -- ^ query

847− -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)

848−createView alias query = UnsafeDefinition $

849− "CREATE" <+> "VIEW" <+> renderQualifiedAlias alias <+> "AS"

850− <+> renderQuery query <> ";"

851−

852−-- | Drop a view.

853−--

854−-- >>> :{

855−-- let

856−-- definition :: Definition

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

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

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

860−-- definition = dropView #bc

861−-- in printSQL definition

862−-- :}

863−-- DROP VIEW "bc";

864−dropView

865− :: (Has sch schemas schema, Has vw schema ('View view))

866− => QualifiedAlias sch vw -- ^ view to remove

867− -> Definition schemas (Alter sch (Drop vw schema) schemas)

868−dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderQualifiedAlias vw <> ";"

869−

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

871−--

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

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

874−createTypeEnum

875− :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)

876− => QualifiedAlias sch enum

877− -- ^ name of the user defined enumerated type

878− -> NP PGlabel labels

879− -- ^ labels of the enumerated type

880− -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)

881−createTypeEnum enum labels = UnsafeDefinition $

882− "CREATE" <+> "TYPE" <+> renderQualifiedAlias enum <+> "AS" <+> "ENUM" <+>

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

884−

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

886−--

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

888−-- >>> instance SOP.Generic Schwarma

889−-- >>> instance SOP.HasDatatypeInfo Schwarma

890−-- >>> :{

891−-- let

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

893−-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma

894−-- in

895−-- printSQL createSchwarma

896−-- :}

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

898−createTypeEnumFrom

899− :: forall hask sch enum schemas schema.

900− ( SOP.Generic hask

901− , SOP.All KnownSymbol (LabelsPG hask)

902− , KnownSymbol enum

903− , Has sch schemas schema )

904− => QualifiedAlias sch enum

905− -- ^ name of the user defined enumerated type

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

907−createTypeEnumFrom enum = createTypeEnum enum

908− (SOP.hpure label :: NP PGlabel (LabelsPG hask))

909−

910−{- | `createTypeComposite` creates a composite type. The composite type is

911−specified by a list of attribute names and data types.

912−

913−>>> :{

914−type PGcomplex = 'PGcomposite

915− '[ "real" ::: 'NotNull 'PGfloat8

916− , "imaginary" ::: 'NotNull 'PGfloat8 ]

917−:}

918−

919−>>> :{

920−let

921− setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]

922− setup = createTypeComposite #complex

923− (float8 `as` #real :* float8 `as` #imaginary)

924−in printSQL setup

925−:}

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

927−-}

928−createTypeComposite

929− :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)

930− => QualifiedAlias sch ty

931− -- ^ name of the user defined composite type

932− -> NP (Aliased (TypeExpression schemas)) fields

933− -- ^ list of attribute names and data types

934− -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)

935−createTypeComposite ty fields = UnsafeDefinition $

936− "CREATE" <+> "TYPE" <+> renderQualifiedAlias ty <+> "AS" <+> parenthesized

937− (renderCommaSeparated renderField fields) <> ";"

938− where

939− renderField :: Aliased (TypeExpression schemas) x -> ByteString

940− renderField (typ `As` alias) =

941− renderAlias alias <+> renderTypeExpression typ

942−

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

944−--

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

946−-- >>> instance SOP.Generic Complex

947−-- >>> instance SOP.HasDatatypeInfo Complex

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

949−-- >>> :{

950−-- let

951−-- createComplex :: Definition (Public '[]) (Public Schema)

952−-- createComplex = createTypeCompositeFrom @Complex #complex

953−-- in

954−-- printSQL createComplex

955−-- :}

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

957−createTypeCompositeFrom

958− :: forall hask sch ty schemas schema.

959− ( SOP.All (FieldTyped schemas) (RowPG hask)

960− , KnownSymbol ty

961− , Has sch schemas schema )

962− => QualifiedAlias sch ty

963− -- ^ name of the user defined composite type

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

965−createTypeCompositeFrom ty = createTypeComposite ty

966− (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype

967− :: NP (Aliased (TypeExpression schemas)) (RowPG hask))

968−

969−class FieldTyped schemas ty where

970− fieldtype :: Aliased (TypeExpression schemas) ty

971−instance (KnownSymbol alias, PGTyped schemas ty)

972− => FieldTyped schemas (alias ::: ty) where

973− fieldtype = pgtype `As` Alias

974−

975−-- | Drop a type.

976−--

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

978−-- >>> instance SOP.Generic Schwarma

979−-- >>> instance SOP.HasDatatypeInfo Schwarma

980−-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))

981−-- DROP TYPE "schwarma";

982−dropType

983− :: (Has sch schemas schema, Has td schema ('Typedef ty))

984− => QualifiedAlias sch td

985− -- ^ name of the user defined type

986− -> Definition schemas (Alter sch (Drop td schema) schemas)

987−dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderQualifiedAlias tydef <> ";"

988−

989−-- | `ColumnTypeExpression`s are used in `createTable` commands.

990−newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)

991− = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }

992− deriving (GHC.Generic,Show,Eq,Ord,NFData)

993−

994−-- | used in `createTable` commands as a column constraint to note that

995−-- @NULL@ may be present in a column

996−nullable

997− :: TypeExpression schemas (nullity ty)

998− -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)

999−nullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NULL"

1000−

1001−-- | used in `createTable` commands as a column constraint to ensure

1002−-- @NULL@ is not present in a column

1003−notNullable

1004− :: TypeExpression schemas (nullity ty)

1005− -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)

1006−notNullable ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NOT NULL"

1007−

1008−-- | used in `createTable` commands as a column constraint to give a default

1009−default_

1010− :: Expression ('[] :=> schemas) '[] 'Ungrouped '[] ty

1011− -> ColumnTypeExpression schemas ('NoDef :=> ty)

1012− -> ColumnTypeExpression schemas ('Def :=> ty)

1013−default_ x ty = UnsafeColumnTypeExpression $

1014− renderColumnTypeExpression ty <+> "DEFAULT" <+> renderExpression x

1015−

1016−-- | not a true type, but merely a notational convenience for creating

1017−-- unique identifier columns with type `PGint2`

1018−serial2, smallserial

1019− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)

1020−serial2 = UnsafeColumnTypeExpression "serial2"

1021−smallserial = UnsafeColumnTypeExpression "smallserial"

1022−-- | not a true type, but merely a notational convenience for creating

1023−-- unique identifier columns with type `PGint4`

1024−serial4, serial

1025− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)

1026−serial4 = UnsafeColumnTypeExpression "serial4"

1027−serial = UnsafeColumnTypeExpression "serial"

1028−-- | not a true type, but merely a notational convenience for creating

1029−-- unique identifier columns with type `PGint8`

1030−serial8, bigserial

1031− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)

1032−serial8 = UnsafeColumnTypeExpression "serial8"

1033−bigserial = UnsafeColumnTypeExpression "bigserial"

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

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Function.hsnew file+238

@@ -0,0 +1,238 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Function

3+Description: Create and drop function and operator definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create and drop function and operator definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Function

33+ ( createFunction

34+ , createOrReplaceFunction

35+ , createSetFunction

36+ , createOrReplaceSetFunction

37+ , createBinaryOp

38+ , createLeftOp

39+ , createRightOp

40+ , dropFunction

41+ , dropFunctionIfExists

42+ , dropOperator

43+ , dropOperatorIfExists

44+ , FunctionDefinition(..)

45+ , languageSqlExpr

46+ , languageSqlQuery

47+ ) where

48+

49+import Control.DeepSeq

50+import Data.ByteString

51+import GHC.TypeLits

52+

53+import qualified Generics.SOP as SOP

54+import qualified GHC.Generics as GHC

55+

56+import Squeal.PostgreSQL.Alias

57+import Squeal.PostgreSQL.Definition

58+import Squeal.PostgreSQL.Expression

59+import Squeal.PostgreSQL.Expression.Type

60+import Squeal.PostgreSQL.List

61+import Squeal.PostgreSQL.Query

62+import Squeal.PostgreSQL.Render

63+import Squeal.PostgreSQL.Schema

64+

65+-- $setup

66+-- >>> import Squeal.PostgreSQL

67+

68+createFunction

69+ :: ( Has sch schemas schema

70+ , KnownSymbol fun

71+ , SOP.SListI args )

72+ => QualifiedAlias sch fun

73+ -> NP (TypeExpression schemas) args

74+ -> TypeExpression schemas ret

75+ -> FunctionDefinition schemas args ('Returns ret)

76+ -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'Returns ret)) schema) schemas)

77+createFunction fun args ret fundef = UnsafeDefinition $

78+ "CREATE" <+> "FUNCTION" <+> renderSQL fun

79+ <+> parenthesized (renderCommaSeparated renderSQL args)

80+ <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"

81+

82+createOrReplaceFunction

83+ :: ( Has sch schemas schema

84+ , KnownSymbol fun

85+ , SOP.SListI args )

86+ => QualifiedAlias sch fun

87+ -> NP (TypeExpression schemas) args

88+ -> TypeExpression schemas ret

89+ -> FunctionDefinition schemas args ('Returns ret)

90+ -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'Returns ret)) schema) schemas)

91+createOrReplaceFunction fun args ret fundef = UnsafeDefinition $

92+ "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun

93+ <+> parenthesized (renderCommaSeparated renderSQL args)

94+ <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"

95+

96+languageSqlExpr

97+ :: Expression '[] '[] 'Ungrouped schemas args '[] ret

98+ -> FunctionDefinition schemas args ('Returns ret)

99+languageSqlExpr expr = UnsafeFunctionDefinition $

100+ "language sql as"

101+ <+> "$$" <+> renderSQL (values_ (expr `as` #ret)) <+> "$$"

102+

103+languageSqlQuery

104+ :: Query '[] '[] schemas args rets

105+ -> FunctionDefinition schemas args ('ReturnsTable rets)

106+languageSqlQuery qry = UnsafeFunctionDefinition $

107+ "language sql as" <+> "$$" <+> renderSQL qry <+> "$$"

108+

109+createSetFunction

110+ :: ( Has sch schemas schema

111+ , KnownSymbol fun

112+ , SOP.SListI args

113+ , SOP.SListI rets )

114+ => QualifiedAlias sch fun

115+ -> NP (TypeExpression schemas) args

116+ -> NP (Aliased (TypeExpression schemas)) rets

117+ -> FunctionDefinition schemas args ('ReturnsTable rets)

118+ -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)

119+createSetFunction fun args rets fundef = UnsafeDefinition $

120+ "CREATE" <+> "FUNCTION" <+> renderSQL fun

121+ <+> parenthesized (renderCommaSeparated renderSQL args)

122+ <+> "RETURNS" <+> "TABLE"

123+ <+> parenthesized (renderCommaSeparated renderRet rets)

124+ <+> renderSQL fundef <> ";"

125+ where

126+ renderRet :: Aliased (TypeExpression s) r -> ByteString

127+ renderRet (ty `As` col) = renderSQL col <+> renderSQL ty

128+

129+createOrReplaceSetFunction

130+ :: ( Has sch schemas schema

131+ , KnownSymbol fun

132+ , SOP.SListI args

133+ , SOP.SListI rets )

134+ => QualifiedAlias sch fun

135+ -> NP (TypeExpression schemas) args

136+ -> NP (Aliased (TypeExpression schemas)) rets

137+ -> FunctionDefinition schemas args ('ReturnsTable rets)

138+ -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)

139+createOrReplaceSetFunction fun args rets fundef = UnsafeDefinition $

140+ "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun

141+ <+> parenthesized (renderCommaSeparated renderSQL args)

142+ <+> "RETURNS" <+> "TABLE"

143+ <+> parenthesized (renderCommaSeparated renderRet rets)

144+ <+> renderSQL fundef <> ";"

145+ where

146+ renderRet :: Aliased (TypeExpression s) r -> ByteString

147+ renderRet (ty `As` col) = renderSQL col <+> renderSQL ty

148+

149+createBinaryOp

150+ :: forall op fun sch schemas schema x y z.

151+ ( Has sch schemas schema

152+ , Has fun schema ('Function ('[x,y] :=> 'Returns z))

153+ , KnownSymbol op )

154+ => QualifiedAlias sch fun

155+ -> TypeExpression schemas x

156+ -> TypeExpression schemas y

157+ -> Definition schemas

158+ (Alter sch (Create op ('Operator ('BinaryOp x y z)) schema) schemas)

159+createBinaryOp fun x y = UnsafeDefinition $

160+ "CREATE" <+> "OPERATOR" <+> renderSymbol @op

161+ <+> parenthesized (commaSeparated opdef)

162+ where

163+ opdef =

164+ [ "FUNCTION" <+> "=" <+> renderSQL fun

165+ , "LEFTARG" <+> "=" <+> renderSQL x

166+ , "RIGHTARG" <+> "=" <+> renderSQL y ]

167+

168+createLeftOp

169+ :: forall op fun sch schemas schema x y.

170+ ( Has sch schemas schema

171+ , Has fun schema ('Function ('[x] :=> 'Returns y))

172+ , KnownSymbol op )

173+ => QualifiedAlias sch fun

174+ -> TypeExpression schemas x

175+ -> Definition schemas

176+ (Alter sch (Create op ('Operator ('LeftOp x y)) schema) schemas)

177+createLeftOp fun x = UnsafeDefinition $

178+ "CREATE" <+> "OPERATOR" <+> renderSymbol @op

179+ <+> parenthesized (commaSeparated opdef)

180+ where

181+ opdef =

182+ [ "FUNCTION" <+> "=" <+> renderSQL fun

183+ , "RIGHTARG" <+> "=" <+> renderSQL x ]

184+

185+createRightOp

186+ :: forall op fun sch schemas schema x y.

187+ ( Has sch schemas schema

188+ , Has fun schema ('Function ('[x] :=> 'Returns y))

189+ , KnownSymbol op )

190+ => QualifiedAlias sch fun

191+ -> TypeExpression schemas x

192+ -> Definition schemas

193+ (Alter sch (Create op ('Operator ('RightOp x y)) schema) schemas)

194+createRightOp fun x = UnsafeDefinition $

195+ "CREATE" <+> "OPERATOR" <+> renderSymbol @op

196+ <+> parenthesized (commaSeparated opdef)

197+ where

198+ opdef =

199+ [ "FUNCTION" <+> "=" <+> renderSQL fun

200+ , "LEFTARG" <+> "=" <+> renderSQL x ]

201+

202+dropFunction

203+ :: (Has sch schemas schema, KnownSymbol fun)

204+ => QualifiedAlias sch fun

205+ -- ^ name of the user defined function

206+ -> Definition schemas (Alter sch (DropSchemum fun 'Function schema) schemas)

207+dropFunction fun = UnsafeDefinition $

208+ "DROP" <+> "FUNCTION" <+> renderSQL fun <> ";"

209+

210+dropFunctionIfExists

211+ :: (Has sch schemas schema, KnownSymbol fun)

212+ => QualifiedAlias sch fun

213+ -- ^ name of the user defined function

214+ -> Definition schemas (Alter sch (DropSchemumIfExists fun 'Function schema) schemas)

215+dropFunctionIfExists fun = UnsafeDefinition $

216+ "DROP FUNCTION IF EXISTS" <+> renderSQL fun <> ";"

217+

218+dropOperator

219+ :: (Has sch schemas schema, KnownSymbol op)

220+ => QualifiedAlias sch op

221+ -- ^ name of the user defined operator

222+ -> Definition schemas (Alter sch (DropSchemum op 'Operator schema) schemas)

223+dropOperator op = UnsafeDefinition $

224+ "DROP" <+> "OPERATOR" <+> renderSQL op <> ";"

225+

226+dropOperatorIfExists

227+ :: (Has sch schemas schema, KnownSymbol op)

228+ => QualifiedAlias sch op

229+ -- ^ name of the user defined operator

230+ -> Definition schemas (Alter sch (DropSchemumIfExists op 'Operator schema) schemas)

231+dropOperatorIfExists op = UnsafeDefinition $

232+ "DROP OPERATOR IF EXISTS" <+> renderSQL op <> ";"

233+

234+newtype FunctionDefinition schemas args ret = UnsafeFunctionDefinition

235+ { renderFunctionDefinition :: ByteString }

236+ deriving (Eq,Show,GHC.Generic,NFData)

237+instance RenderSQL (FunctionDefinition schemas args ret) where

238+ renderSQL = renderFunctionDefinition

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Index.hsnew file+159

@@ -0,0 +1,159 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Index

3+Description: Create and drop index definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create and drop index definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Index

33+ ( createIndex

34+ , createIndexIfNotExists

35+ , dropIndex

36+ , dropIndexIfExists

37+ , IndexMethod (..)

38+ , btree

39+ , hash

40+ , gist

41+ , spgist

42+ , gin

43+ , brin

44+ ) where

45+

46+import Data.ByteString

47+import GHC.TypeLits

48+

49+import qualified GHC.Generics as GHC

50+

51+import Squeal.PostgreSQL.Alias

52+import Squeal.PostgreSQL.Definition

53+import Squeal.PostgreSQL.Expression.Sort

54+import Squeal.PostgreSQL.Render

55+import Squeal.PostgreSQL.Schema

56+

57+-- $setup

58+-- >>> import Squeal.PostgreSQL

59+

60+{- |

61+>>> :{

62+type Table = '[] :=>

63+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4

64+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

65+:}

66+

67+>>> :{

68+let

69+ setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table, "ix" ::: 'Index 'Btree])

70+ setup =

71+ createTable #tab (nullable int `as` #a :* nullable real `as` #b) Nil >>>

72+ createIndex #ix #tab btree [#a & AscNullsFirst, #b & AscNullsLast]

73+in printSQL setup

74+:}

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

76+CREATE INDEX "ix" ON "tab" USING btree (("a") ASC NULLS FIRST, ("b") ASC NULLS LAST);

77+-}

78+createIndex

79+ :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)

80+ => Alias ix

81+ -> QualifiedAlias sch tab

82+ -> IndexMethod method

83+ -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]

84+ -> Definition schemas (Alter sch (Create ix ('Index method) schema) schemas)

85+createIndex ix tab method cols = UnsafeDefinition $

86+ "CREATE" <+> "INDEX" <+> renderSQL ix <+> "ON" <+> renderSQL tab

87+ <+> "USING" <+> renderSQL method

88+ <+> parenthesized (commaSeparated (renderIndex <$> cols))

89+ <> ";"

90+ where

91+ renderIndex = \case

92+ Asc expression -> parenthesized (renderSQL expression) <+> "ASC"

93+ Desc expression -> parenthesized (renderSQL expression) <+> "DESC"

94+ AscNullsFirst expression -> parenthesized (renderSQL expression)

95+ <+> "ASC NULLS FIRST"

96+ DescNullsFirst expression -> parenthesized (renderSQL expression)

97+ <+> "DESC NULLS FIRST"

98+ AscNullsLast expression -> parenthesized (renderSQL expression)

99+ <+> "ASC NULLS LAST"

100+ DescNullsLast expression -> parenthesized (renderSQL expression)

101+ <+> "DESC NULLS LAST"

102+

103+createIndexIfNotExists

104+ :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)

105+ => Alias ix

106+ -> QualifiedAlias sch tab

107+ -> IndexMethod method

108+ -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]

109+ -> Definition schemas (Alter sch (CreateIfNotExists ix ('Index method) schema) schemas)

110+createIndexIfNotExists ix tab method cols = UnsafeDefinition $

111+ "CREATE INDEX IF NOT EXISTS" <+> renderSQL ix <+> "ON" <+> renderSQL tab

112+ <+> "USING" <+> renderSQL method

113+ <+> parenthesized (commaSeparated (renderIndex <$> cols))

114+ <> ";"

115+ where

116+ renderIndex = \case

117+ Asc expression -> parenthesized (renderSQL expression) <+> "ASC"

118+ Desc expression -> parenthesized (renderSQL expression) <+> "DESC"

119+ AscNullsFirst expression -> parenthesized (renderSQL expression)

120+ <+> "ASC NULLS FIRST"

121+ DescNullsFirst expression -> parenthesized (renderSQL expression)

122+ <+> "DESC NULLS FIRST"

123+ AscNullsLast expression -> parenthesized (renderSQL expression)

124+ <+> "ASC NULLS LAST"

125+ DescNullsLast expression -> parenthesized (renderSQL expression)

126+ <+> "DESC NULLS LAST"

127+

128+newtype IndexMethod ty = UnsafeIndexMethod {renderIndexMethod :: ByteString}

129+ deriving stock (Eq, Ord, Show, GHC.Generic)

130+instance RenderSQL (IndexMethod ty) where renderSQL = renderIndexMethod

131+btree :: IndexMethod 'Btree

132+btree = UnsafeIndexMethod "btree"

133+hash :: IndexMethod 'Hash

134+hash = UnsafeIndexMethod "hash"

135+gist :: IndexMethod 'Gist

136+gist = UnsafeIndexMethod "gist"

137+spgist :: IndexMethod 'Spgist

138+spgist = UnsafeIndexMethod "spgist"

139+gin :: IndexMethod 'Gin

140+gin = UnsafeIndexMethod "gin"

141+brin :: IndexMethod 'Brin

142+brin = UnsafeIndexMethod "brin"

143+

144+-- |

145+-- >>> printSQL (dropIndex #ix :: Definition (Public '["ix" ::: 'Index 'Btree]) (Public '[]))

146+-- DROP INDEX "ix";

147+dropIndex

148+ :: (Has sch schemas schema, KnownSymbol ix)

149+ => QualifiedAlias sch ix

150+ -- ^ name of the user defined index

151+ -> Definition schemas (Alter sch (DropSchemum ix 'Index schema) schemas)

152+dropIndex ix = UnsafeDefinition $ "DROP" <+> "INDEX" <+> renderSQL ix <> ";"

153+

154+dropIndexIfExists

155+ :: (Has sch schemas schema, KnownSymbol ix)

156+ => QualifiedAlias sch ix

157+ -- ^ name of the user defined index

158+ -> Definition schemas (Alter sch (DropSchemumIfExists ix 'Index schema) schemas)

159+dropIndexIfExists ix = UnsafeDefinition $ "DROP INDEX IF EXISTS" <+> renderSQL ix <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Schema.hsnew file+96

@@ -0,0 +1,96 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Schema

3+Description: Create and drop schema definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create and drop schema definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Schema

33+ ( createSchema

34+ , createSchemaIfNotExists

35+ , dropSchema

36+ , dropSchemaIfExists

37+ ) where

38+

39+import GHC.TypeLits

40+

41+import Squeal.PostgreSQL.Alias

42+import Squeal.PostgreSQL.Definition

43+import Squeal.PostgreSQL.Render

44+import Squeal.PostgreSQL.Schema

45+

46+-- $setup

47+-- >>> import Squeal.PostgreSQL

48+

49+{- |

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

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

52+in the current database.

53+

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

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

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

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

58+name as a prefix.

59+-}

60+createSchema

61+ :: KnownSymbol sch

62+ => Alias sch

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

64+createSchema sch = UnsafeDefinition $

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

66+

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

68+createSchemaIfNotExists

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

70+ => Alias sch

71+ -> Definition schemas (CreateIfNotExists sch '[] schemas)

72+createSchemaIfNotExists sch = UnsafeDefinition $

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

74+ <+> renderSQL sch <> ";"

75+

76+-- | >>> :{

77+-- let

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

79+-- definition = dropSchema #muh_schema

80+-- :}

81+--

82+-- >>> printSQL definition

83+-- DROP SCHEMA "muh_schema";

84+dropSchema

85+ :: KnownSymbol sch

86+ => Alias sch

87+ -- ^ user defined schema

88+ -> Definition schemas (Drop sch schemas)

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

90+

91+dropSchemaIfExists

92+ :: KnownSymbol sch

93+ => Alias sch

94+ -- ^ user defined schema

95+ -> Definition schemas (DropIfExists sch schemas)

96+dropSchemaIfExists sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table.hsnew file+500

@@ -0,0 +1,500 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Table

3+Description: Create, drop and alter table definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create, drop and alter table definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Table

33+ ( createTable

34+ , createTableIfNotExists

35+ , dropTable

36+ , dropTableIfExists

37+ , alterTable

38+ , alterTableIfExists

39+ , alterTableRename

40+ , alterTableIfExistsRename

41+ , AlterTable (..)

42+ , addConstraint

43+ , dropConstraint

44+ , AddColumn (..)

45+ , dropColumn

46+ , renameColumn

47+ , alterColumn

48+ , AlterColumn (..)

49+ , setDefault

50+ , dropDefault

51+ , setNotNull

52+ , dropNotNull

53+ , alterType

54+ ) where

55+

56+import Control.DeepSeq

57+import Data.ByteString

58+import GHC.TypeLits

59+

60+import qualified Generics.SOP as SOP

61+import qualified GHC.Generics as GHC

62+

63+import Squeal.PostgreSQL.Alias

64+import Squeal.PostgreSQL.Definition

65+import Squeal.PostgreSQL.Definition.Table.Constraint

66+import Squeal.PostgreSQL.Expression

67+import Squeal.PostgreSQL.Expression.Type

68+import Squeal.PostgreSQL.List

69+import Squeal.PostgreSQL.Render

70+import Squeal.PostgreSQL.Schema

71+

72+-- $setup

73+-- >>> import Squeal.PostgreSQL

74+

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

76+

77+>>> :set -XOverloadedLabels

78+>>> :{

79+type Table = '[] :=>

80+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4

81+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

82+:}

83+

84+>>> :{

85+let

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

87+ setup = createTable #tab

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

89+in printSQL setup

90+:}

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

92+-}

93+createTable

94+ :: ( KnownSymbol sch

95+ , KnownSymbol tab

96+ , columns ~ (col ': cols)

97+ , SOP.SListI columns

98+ , SOP.SListI constraints

99+ , Has sch schemas0 schema0

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

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

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

103+ -- ^ the names and datatype of each column

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

105+ -- ^ constraints that must hold for the table

106+ -> Definition schemas0 schemas1

107+createTable tab columns constraints = UnsafeDefinition $

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

109+

110+{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.

111+Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.

112+`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in

113+the `Category` of `Definition`s.

114+

115+>>> :set -XOverloadedLabels -XTypeApplications

116+>>> :{

117+type Table = '[] :=>

118+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4

119+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]

120+:}

121+

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

123+

124+>>> :{

125+let

126+ setup :: Definition Schemas Schemas

127+ setup = createTableIfNotExists #tab

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

129+in printSQL setup

130+:}

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

132+-}

133+createTableIfNotExists

134+ :: ( KnownSymbol sch

135+ , KnownSymbol tab

136+ , columns ~ (col ': cols)

137+ , SOP.SListI columns

138+ , SOP.SListI constraints

139+ , Has sch schemas0 schema0

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

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

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

143+ -- ^ the names and datatype of each column

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

145+ -- ^ constraints that must hold for the table

146+ -> Definition schemas0 schemas1

147+createTableIfNotExists tab columns constraints = UnsafeDefinition $

148+ "CREATE TABLE IF NOT EXISTS"

149+ <+> renderCreation tab columns constraints

150+

151+-- helper function for `createTable` and `createTableIfNotExists`

152+renderCreation

153+ :: ( KnownSymbol sch

154+ , KnownSymbol tab

155+ , SOP.SListI columns

156+ , SOP.SListI constraints )

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

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

159+ -- ^ the names and datatype of each column

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

161+ -- ^ constraints that must hold for the table

162+ -> ByteString

163+renderCreation tab columns constraints = renderSQL tab

164+ <+> parenthesized

165+ ( renderCommaSeparated renderColumnDef columns

166+ <> ( case constraints of

167+ Nil -> ""

168+ _ -> ", " <>

169+ renderCommaSeparated renderConstraint constraints ) )

170+ <> ";"

171+ where

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

173+ renderColumnDef (ty `As` column) =

174+ renderSQL column <+> renderColumnTypeExpression ty

175+ renderConstraint

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

177+ -> ByteString

178+ renderConstraint (constraint `As` alias) =

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

180+

181+-- | `dropTable` removes a table from the schema.

182+--

183+-- >>> :{

184+-- let

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

186+-- definition = dropTable #muh_table

187+-- :}

188+--

189+-- >>> printSQL definition

190+-- DROP TABLE "muh_table";

191+dropTable

192+ :: ( Has sch schemas schema

193+ , KnownSymbol tab )

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

195+ -> Definition schemas (Alter sch (DropSchemum tab 'Table schema) schemas)

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

197+

198+dropTableIfExists

199+ :: ( Has sch schemas schema

200+ , KnownSymbol tab)

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

202+ -> Definition schemas (Alter sch (DropSchemumIfExists tab 'Table schema) schemas)

203+dropTableIfExists tab = UnsafeDefinition $ "DROP TABLE IF EXISTS" <+> renderSQL tab <> ";"

204+

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

206+alterTable

207+ :: (Has sch schemas schema, KnownSymbol tab)

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

209+ -> AlterTable sch tab schemas table -- ^ alteration to perform

210+ -> Definition schemas (Alter sch (Alter tab ('Table table) schema) schemas)

211+alterTable tab alteration = UnsafeDefinition $

212+ "ALTER TABLE"

213+ <+> renderSQL tab

214+ <+> renderAlterTable alteration

215+ <> ";"

216+

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

218+alterTableIfExists

219+ :: (Has sch schemas schema, KnownSymbol tab)

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

221+ -> AlterTable sch tab schemas table -- ^ alteration to perform

222+ -> Definition schemas (Alter sch (AlterIfExists tab ('Table table) schema) schemas)

223+alterTableIfExists tab alteration = UnsafeDefinition $

224+ "ALTER TABLE IF EXISTS"

225+ <+> renderSQL tab

226+ <+> renderAlterTable alteration

227+ <> ";"

228+

229+-- | `alterTableRename` changes the name of a table from the schema.

230+--

231+-- >>> printSQL $ alterTableRename #foo #bar

232+-- ALTER TABLE "foo" RENAME TO "bar";

233+alterTableRename

234+ :: (KnownSymbol tab0, KnownSymbol tab1)

235+ => Alias tab0 -- ^ table to rename

236+ -> Alias tab1 -- ^ what to rename it

237+ -> Definition schema (Rename tab0 tab1 schema)

238+alterTableRename tab0 tab1 = UnsafeDefinition $

239+ "ALTER TABLE" <+> renderSQL tab0

240+ <+> "RENAME TO" <+> renderSQL tab1 <> ";"

241+

242+alterTableIfExistsRename

243+ :: (KnownSymbol tab0, KnownSymbol tab1)

244+ => Alias tab0 -- ^ table to rename

245+ -> Alias tab1 -- ^ what to rename it

246+ -> Definition schema (RenameIfExists tab0 tab1 schema)

247+alterTableIfExistsRename tab0 tab1 = UnsafeDefinition $

248+ "ALTER TABLE IF EXISTS" <+> renderSQL tab0

249+ <+> "RENAME TO" <+> renderSQL tab1 <> ";"

250+

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

252+-- of a table.

253+newtype AlterTable

254+ (sch :: Symbol)

255+ (tab :: Symbol)

256+ (schemas :: SchemasType)

257+ (table :: TableType) =

258+ UnsafeAlterTable {renderAlterTable :: ByteString}

259+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

260+

261+-- | An `addConstraint` adds a table constraint.

262+--

263+-- >>> :{

264+-- let

265+-- definition :: Definition

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

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

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

269+-- in printSQL definition

270+-- :}

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

272+addConstraint

273+ :: ( KnownSymbol alias

274+ , Has sch schemas schema

275+ , Has tab schema ('Table table0)

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

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

278+ => Alias alias

279+ -> TableConstraintExpression sch tab schemas constraint

280+ -- ^ constraint to add

281+ -> AlterTable sch tab schemas table1

282+addConstraint alias constraint = UnsafeAlterTable $

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

284+ <+> renderSQL constraint

285+

286+-- | A `dropConstraint` drops a table constraint.

287+--

288+-- >>> :{

289+-- let

290+-- definition :: Definition

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

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

293+-- definition = alterTable #tab (dropConstraint #positive)

294+-- in printSQL definition

295+-- :}

296+-- ALTER TABLE "tab" DROP CONSTRAINT "positive";

297+dropConstraint

298+ :: ( KnownSymbol constraint

299+ , Has sch schemas schema

300+ , Has tab schema ('Table table0)

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

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

303+ => Alias constraint

304+ -- ^ constraint to drop

305+ -> AlterTable sch tab schemas table1

306+dropConstraint constraint = UnsafeAlterTable $

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

308+

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

310+class AddColumn ty where

311+ -- | `addColumn` adds a new column, initially filled with whatever

312+ -- default value is given or with @NULL@.

313+ --

314+ -- >>> :{

315+ -- let

316+ -- definition :: Definition

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

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

319+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

322+ -- in printSQL definition

323+ -- :}

324+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';

325+ --

326+ -- >>> :{

327+ -- let

328+ -- definition :: Definition

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

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

331+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

334+ -- in printSQL definition

335+ -- :}

336+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;

337+ addColumn

338+ :: ( KnownSymbol column

339+ , Has sch schemas schema

340+ , Has tab schema ('Table table0)

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

342+ => Alias column -- ^ column to add

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

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

345+ addColumn column ty = UnsafeAlterTable $

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

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

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

349+

350+-- | A `dropColumn` removes a column. Whatever data was in the column

351+-- disappears. Table constraints involving the column are dropped, too.

352+-- However, if the column is referenced by a foreign key constraint of

353+-- another table, PostgreSQL will not silently drop that constraint.

354+--

355+-- >>> :{

356+-- let

357+-- definition :: Definition

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

359+-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

362+-- definition = alterTable #tab (dropColumn #col2)

363+-- in printSQL definition

364+-- :}

365+-- ALTER TABLE "tab" DROP COLUMN "col2";

366+dropColumn

367+ :: ( KnownSymbol column

368+ , Has sch schemas schema

369+ , Has tab schema ('Table table0)

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

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

372+ => Alias column -- ^ column to remove

373+ -> AlterTable sch tab schemas table1

374+dropColumn column = UnsafeAlterTable $

375+ "DROP COLUMN" <+> renderSQL column

376+

377+-- | A `renameColumn` renames a column.

378+--

379+-- >>> :{

380+-- let

381+-- definition :: Definition

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

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

384+-- definition = alterTable #tab (renameColumn #foo #bar)

385+-- in printSQL definition

386+-- :}

387+-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";

388+renameColumn

389+ :: ( KnownSymbol column0

390+ , KnownSymbol column1

391+ , Has sch schemas schema

392+ , Has tab schema ('Table table0)

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

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

395+ => Alias column0 -- ^ column to rename

396+ -> Alias column1 -- ^ what to rename the column

397+ -> AlterTable sch tab schemas table1

398+renameColumn column0 column1 = UnsafeAlterTable $

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

400+

401+-- | An `alterColumn` alters a single column.

402+alterColumn

403+ :: ( KnownSymbol column

404+ , Has sch schemas schema

405+ , Has tab schema ('Table table0)

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

407+ , Has column columns ty0

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

409+ => Alias column -- ^ column to alter

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

411+ -> AlterTable sch tab schemas table1

412+alterColumn column alteration = UnsafeAlterTable $

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

414+

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

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

417+ UnsafeAlterColumn {renderAlterColumn :: ByteString}

418+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

419+

420+-- | A `setDefault` sets a new default for a column. Note that this doesn't

421+-- affect any existing rows in the table, it just changes the default for

422+-- future insert and update commands.

423+--

424+-- >>> :{

425+-- let

426+-- definition :: Definition

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

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

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

430+-- in printSQL definition

431+-- :}

432+-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;

433+setDefault

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

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

436+setDefault expression = UnsafeAlterColumn $

437+ "SET DEFAULT" <+> renderExpression expression

438+

439+-- | A `dropDefault` removes any default value for a column.

440+--

441+-- >>> :{

442+-- let

443+-- definition :: Definition

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

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

446+-- definition = alterTable #tab (alterColumn #col dropDefault)

447+-- in printSQL definition

448+-- :}

449+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;

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

451+dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

452+

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

454+-- The constraint will be checked immediately, so the table data must satisfy

455+-- the constraint before it can be added.

456+--

457+-- >>> :{

458+-- let

459+-- definition :: Definition

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

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

462+-- definition = alterTable #tab (alterColumn #col setNotNull)

463+-- in printSQL definition

464+-- :}

465+-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;

466+setNotNull

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

468+setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

469+

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

471+--

472+-- >>> :{

473+-- let

474+-- definition :: Definition

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

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

477+-- definition = alterTable #tab (alterColumn #col dropNotNull)

478+-- in printSQL definition

479+-- :}

480+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;

481+dropNotNull

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

483+dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

484+

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

486+-- This will succeed only if each existing entry in the column can be

487+-- converted to the new type by an implicit cast.

488+--

489+-- >>> :{

490+-- let

491+-- definition :: Definition

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

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

494+-- definition =

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

496+-- in printSQL definition

497+-- :}

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

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

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

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table/Constraint.hsnew file+339

@@ -0,0 +1,339 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Table.Constraint

3+Description: Table constraint expressions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Table constraint expressions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Table.Constraint

33+ ( TableConstraintExpression (..)

34+ , check

35+ , unique

36+ , primaryKey

37+ , foreignKey

38+ , ForeignKeyed

39+ , OnDeleteClause (..)

40+ , OnUpdateClause (..)

41+ ) where

42+

43+import Control.DeepSeq

44+import Data.ByteString

45+import GHC.TypeLits

46+

47+import qualified Generics.SOP as SOP

48+import qualified GHC.Generics as GHC

49+

50+import Squeal.PostgreSQL.Alias

51+import Squeal.PostgreSQL.Expression.Logic

52+import Squeal.PostgreSQL.List

53+import Squeal.PostgreSQL.Render

54+import Squeal.PostgreSQL.Schema

55+

56+-- $setup

57+-- >>> import Squeal.PostgreSQL

58+

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

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

61+-- too coarse. For example, a column containing a product price should

62+-- probably only accept positive values. But there is no standard data type

63+-- that accepts only positive numbers. Another issue is that you might want

64+-- to constrain column data with respect to other columns or rows.

65+-- For example, in a table containing product information,

66+-- there should be only one row for each product number.

67+-- `TableConstraint`s give you as much control over the data in your tables

68+-- as you wish. If a user attempts to store data in a column that would

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

70+-- even if the value came from the default value definition.

71+newtype TableConstraintExpression

72+ (sch :: Symbol)

73+ (tab :: Symbol)

74+ (schemas :: SchemasType)

75+ (constraint :: TableConstraint)

76+ = UnsafeTableConstraintExpression

77+ { renderTableConstraintExpression :: ByteString }

78+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

79+instance RenderSQL

80+ (TableConstraintExpression sch tab schemas constraint) where

81+ renderSQL = renderTableConstraintExpression

82+

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

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

85+a Boolean (truth-value) expression.

86+

87+>>> :{

88+type Schema = '[

89+ "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[

90+ "a" ::: 'NoDef :=> 'NotNull 'PGint4,

91+ "b" ::: 'NoDef :=> 'NotNull 'PGint4

92+ ])]

93+:}

94+

95+>>> :{

96+let

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

98+ definition = createTable #tab

99+ ( (int & notNullable) `as` #a :*

100+ (int & notNullable) `as` #b )

101+ ( check (#a :* #b) (#a .> #b) `as` #inequality )

102+:}

103+

104+>>> printSQL definition

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

106+-}

107+check

108+ :: ( Has sch schemas schema

109+ , Has tab schema ('Table table)

110+ , HasAll aliases (TableToRow table) subcolumns )

111+ => NP Alias aliases

112+ -- ^ specify the subcolumns which are getting checked

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

114+ -- ^ a closed `Condition` on those subcolumns

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

116+check _cols condition = UnsafeTableConstraintExpression $

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

118+

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

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

121+

122+>>> :{

123+type Schema = '[

124+ "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[

125+ "a" ::: 'NoDef :=> 'Null 'PGint4,

126+ "b" ::: 'NoDef :=> 'Null 'PGint4

127+ ])]

128+:}

129+

130+>>> :{

131+let

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

133+ definition = createTable #tab

134+ ( (int & nullable) `as` #a :*

135+ (int & nullable) `as` #b )

136+ ( unique (#a :* #b) `as` #uq_a_b )

137+:}

138+

139+>>> printSQL definition

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

141+-}

142+unique

143+ :: ( Has sch schemas schema

144+ , Has tab schema('Table table)

145+ , HasAll aliases (TableToRow table) subcolumns )

146+ => NP Alias aliases

147+ -- ^ specify subcolumns which together are unique for each row

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

149+unique columns = UnsafeTableConstraintExpression $

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

151+

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

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

154+This requires that the values be both unique and not null.

155+

156+>>> :{

157+type Schema = '[

158+ "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[

159+ "id" ::: 'Def :=> 'NotNull 'PGint4,

160+ "name" ::: 'NoDef :=> 'NotNull 'PGtext

161+ ])]

162+:}

163+

164+>>> :{

165+let

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

167+ definition = createTable #tab

168+ ( serial `as` #id :*

169+ (text & notNullable) `as` #name )

170+ ( primaryKey #id `as` #pk_id )

171+:}

172+

173+>>> printSQL definition

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

175+-}

176+primaryKey

177+ :: ( Has sch schemas schema

178+ , Has tab schema ('Table table)

179+ , HasAll aliases (TableToColumns table) subcolumns

180+ , AllNotNull subcolumns )

181+ => NP Alias aliases

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

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

184+primaryKey columns = UnsafeTableConstraintExpression $

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

186+

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

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

189+another table. We say this maintains the referential integrity

190+between two related tables.

191+

192+>>> :{

193+type Schema =

194+ '[ "users" ::: 'Table (

195+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

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

197+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

198+ ])

199+ , "emails" ::: 'Table (

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

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

202+ ] :=>

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

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

205+ , "email" ::: 'NoDef :=> 'Null 'PGtext

206+ ])

207+ ]

208+:}

209+

210+>>> :{

211+let

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

213+ setup =

214+ createTable #users

215+ ( serial `as` #id :*

216+ (text & notNullable) `as` #name )

217+ ( primaryKey #id `as` #pk_users ) >>>

218+ createTable #emails

219+ ( serial `as` #id :*

220+ (int & notNullable) `as` #user_id :*

221+ (text & nullable) `as` #email )

222+ ( primaryKey #id `as` #pk_emails :*

223+ foreignKey #user_id #users #id

224+ OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

225+in printSQL setup

226+:}

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

228+CREATE TABLE "emails" ("id" serial, "user_id" int NOT NULL, "email" text NULL, CONSTRAINT "pk_emails" PRIMARY KEY ("id"), CONSTRAINT "fk_user_id" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE ON UPDATE CASCADE);

229+

230+A `foreignKey` can even be a table self-reference.

231+

232+>>> :{

233+type Schema =

234+ '[ "employees" ::: 'Table (

235+ '[ "employees_pk" ::: 'PrimaryKey '["id"]

236+ , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]

237+ ] :=>

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

239+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

240+ , "employer_id" ::: 'NoDef :=> 'Null 'PGint4

241+ ])

242+ ]

243+:}

244+

245+>>> :{

246+let

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

248+ setup =

249+ createTable #employees

250+ ( serial `as` #id :*

251+ (text & notNullable) `as` #name :*

252+ (integer & nullable) `as` #employer_id )

253+ ( primaryKey #id `as` #employees_pk :*

254+ foreignKey #employer_id #employees #id

255+ OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )

256+in printSQL setup

257+:}

258+CREATE TABLE "employees" ("id" serial, "name" text NOT NULL, "employer_id" integer NULL, CONSTRAINT "employees_pk" PRIMARY KEY ("id"), CONSTRAINT "employees_employer_fk" FOREIGN KEY ("employer_id") REFERENCES "employees" ("id") ON DELETE CASCADE ON UPDATE CASCADE);

259+-}

260+foreignKey

261+ :: (ForeignKeyed schemas sch schema child parent

262+ table reftable

263+ columns refcolumns

264+ constraints cols

265+ reftys tys )

266+ => NP Alias columns

267+ -- ^ column or columns in the table

268+ -> Alias parent

269+ -- ^ reference table

270+ -> NP Alias refcolumns

271+ -- ^ reference column or columns in the reference table

272+ -> OnDeleteClause

273+ -- ^ what to do when reference is deleted

274+ -> OnUpdateClause

275+ -- ^ what to do when reference is updated

276+ -> TableConstraintExpression sch child schemas

277+ ('ForeignKey columns parent refcolumns)

278+foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $

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

280+ <+> "REFERENCES" <+> renderSQL parent

281+ <+> parenthesized (renderSQL refs)

282+ <+> renderSQL ondel

283+ <+> renderSQL onupd

284+

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

286+type ForeignKeyed schemas

287+ sch

288+ schema

289+ child parent

290+ table reftable

291+ columns refcolumns

292+ constraints cols

293+ reftys tys =

294+ ( Has sch schemas schema

295+ , Has child schema ('Table table)

296+ , Has parent schema ('Table reftable)

297+ , HasAll columns (TableToColumns table) tys

298+ , reftable ~ (constraints :=> cols)

299+ , HasAll refcolumns cols reftys

300+ , SOP.AllZip SamePGType tys reftys

301+ , Uniquely refcolumns constraints )

302+

303+-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.

304+data OnDeleteClause

305+ = OnDeleteNoAction

306+ -- ^ if any referencing rows still exist when the constraint is checked,

307+ -- an error is raised

308+ | OnDeleteRestrict -- ^ prevents deletion of a referenced row

309+ | OnDeleteCascade

310+ -- ^ specifies that when a referenced row is deleted,

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

312+ deriving (GHC.Generic,Show,Eq,Ord)

313+instance NFData OnDeleteClause

314+-- | Render `OnDeleteClause`.

315+instance RenderSQL OnDeleteClause where

316+ renderSQL = \case

317+ OnDeleteNoAction -> "ON DELETE NO ACTION"

318+ OnDeleteRestrict -> "ON DELETE RESTRICT"

319+ OnDeleteCascade -> "ON DELETE CASCADE"

320+

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

322+-- when a referenced column is changed (updated).

323+data OnUpdateClause

324+ = OnUpdateNoAction

325+ -- ^ if any referencing rows has not changed when the constraint is checked,

326+ -- an error is raised

327+ | OnUpdateRestrict -- ^ prevents update of a referenced row

328+ | OnUpdateCascade

329+ -- ^ the updated values of the referenced column(s) should be copied

330+ -- into the referencing row(s)

331+ deriving (GHC.Generic,Show,Eq,Ord)

332+instance NFData OnUpdateClause

333+

334+-- | Render `OnUpdateClause`.

335+instance RenderSQL OnUpdateClause where

336+ renderSQL = \case

337+ OnUpdateNoAction -> "ON UPDATE NO ACTION"

338+ OnUpdateRestrict -> "ON UPDATE RESTRICT"

339+ OnUpdateCascade -> "ON UPDATE CASCADE"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Type.hsnew file+229

@@ -0,0 +1,229 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.Type

3+Description: Create and drop type definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create and drop type definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.Type

33+ ( createTypeEnum

34+ , createTypeEnumFrom

35+ , createTypeComposite

36+ , createTypeCompositeFrom

37+ , createTypeRange

38+ , createDomain

39+ , dropType

40+ , dropTypeIfExists

41+ ) where

42+

43+import Data.ByteString

44+import Data.Monoid

45+import GHC.TypeLits

46+import Prelude hiding ((.), id)

47+

48+import qualified Generics.SOP as SOP

49+

50+import Squeal.PostgreSQL.Alias

51+import Squeal.PostgreSQL.Expression.Logic

52+import Squeal.PostgreSQL.Expression.Type

53+import Squeal.PostgreSQL.Definition

54+import Squeal.PostgreSQL.List

55+import Squeal.PostgreSQL.PG

56+import Squeal.PostgreSQL.Render

57+import Squeal.PostgreSQL.Schema

58+

59+-- $setup

60+-- >>> import Squeal.PostgreSQL

61+-- >>> import qualified GHC.Generics as GHC

62+-- >>> import qualified Generics.SOP as SOP

63+

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

65+--

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

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

68+createTypeEnum

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

70+ => QualifiedAlias sch enum

71+ -- ^ name of the user defined enumerated type

72+ -> NP PGlabel labels

73+ -- ^ labels of the enumerated type

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

75+createTypeEnum enum labels = UnsafeDefinition $

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

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

78+

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

80+--

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

82+-- >>> instance SOP.Generic Schwarma

83+-- >>> instance SOP.HasDatatypeInfo Schwarma

84+-- >>> :{

85+-- let

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

87+-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma

88+-- in

89+-- printSQL createSchwarma

90+-- :}

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

92+createTypeEnumFrom

93+ :: forall hask sch enum schemas schema.

94+ ( SOP.Generic hask

95+ , SOP.All KnownSymbol (LabelsPG hask)

96+ , KnownSymbol enum

97+ , Has sch schemas schema )

98+ => QualifiedAlias sch enum

99+ -- ^ name of the user defined enumerated type

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

101+createTypeEnumFrom enum = createTypeEnum enum

102+ (SOP.hpure label :: NP PGlabel (LabelsPG hask))

103+

104+{- | `createTypeComposite` creates a composite type. The composite type is

105+specified by a list of attribute names and data types.

106+

107+>>> :{

108+type PGcomplex = 'PGcomposite

109+ '[ "real" ::: 'NotNull 'PGfloat8

110+ , "imaginary" ::: 'NotNull 'PGfloat8 ]

111+:}

112+

113+>>> :{

114+let

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

116+ setup = createTypeComposite #complex

117+ (float8 `as` #real :* float8 `as` #imaginary)

118+in printSQL setup

119+:}

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

121+-}

122+createTypeComposite

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

124+ => QualifiedAlias sch ty

125+ -- ^ name of the user defined composite type

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

127+ -- ^ list of attribute names and data types

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

129+createTypeComposite ty fields = UnsafeDefinition $

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

131+ (renderCommaSeparated renderField fields) <> ";"

132+ where

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

134+ renderField (typ `As` alias) =

135+ renderSQL alias <+> renderSQL typ

136+

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

138+--

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

140+-- >>> instance SOP.Generic Complex

141+-- >>> instance SOP.HasDatatypeInfo Complex

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

143+-- >>> :{

144+-- let

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

146+-- createComplex = createTypeCompositeFrom @Complex #complex

147+-- in

148+-- printSQL createComplex

149+-- :}

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

151+createTypeCompositeFrom

152+ :: forall hask sch ty schemas schema.

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

154+ , KnownSymbol ty

155+ , Has sch schemas schema )

156+ => QualifiedAlias sch ty

157+ -- ^ name of the user defined composite type

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

159+createTypeCompositeFrom ty = createTypeComposite ty

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

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

162+

163+{-|

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

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

166+

167+Domains are useful for abstracting common constraints on fields

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

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

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

171+each table's constraint individually.

172+

173+>>> :{

174+let

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

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

177+in printSQL createPositive

178+:}

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

180+-}

181+createDomain

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

183+ => QualifiedAlias sch dom

184+ -> (forall null. TypeExpression schemas (null ty))

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

186+ -> Definition schemas (Alter sch (Create dom ('Typedef ty) schema) schemas)

187+createDomain dom ty condition =

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

189+ <+> "AS" <+> renderTypeExpression ty

190+ <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"

191+

192+{- |

193+>>> :{

194+let

195+ createSmallIntRange :: Definition (Public '[]) (Public '["int2range" ::: 'Typedef ('PGrange 'PGint2)])

196+ createSmallIntRange = createTypeRange #int2range int2

197+in printSQL createSmallIntRange

198+:}

199+CREATE TYPE "int2range" AS RANGE (subtype = int2);

200+-}

201+createTypeRange

202+ :: (Has sch schemas schema, KnownSymbol range)

203+ => QualifiedAlias sch range

204+ -> (forall null. TypeExpression schemas (null ty))

205+ -> Definition schemas (Alter sch (Create range ('Typedef ('PGrange ty)) schema) schemas)

206+createTypeRange range ty = UnsafeDefinition $

207+ "CREATE" <+> "TYPE" <+> renderSQL range <+> "AS" <+> "RANGE" <+>

208+ parenthesized ("subtype" <+> "=" <+> renderTypeExpression ty) <> ";"

209+

210+-- | Drop a type.

211+--

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

213+-- >>> instance SOP.Generic Schwarma

214+-- >>> instance SOP.HasDatatypeInfo Schwarma

215+-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))

216+-- DROP TYPE "schwarma";

217+dropType

218+ :: (Has sch schemas schema, KnownSymbol td)

219+ => QualifiedAlias sch td

220+ -- ^ name of the user defined type

221+ -> Definition schemas (Alter sch (DropSchemum td 'Typedef schema) schemas)

222+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"

223+

224+dropTypeIfExists

225+ :: (Has sch schemas schema, KnownSymbol td)

226+ => QualifiedAlias sch td

227+ -- ^ name of the user defined type

228+ -> Definition schemas (Alter sch (DropSchemumIfExists td 'Typedef schema) schemas)

229+dropTypeIfExists tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/View.hsnew file+104

@@ -0,0 +1,104 @@

1+{-|

2+Module: Squeal.PostgreSQL.Definition.View

3+Description: Create and drop view definitions

4+Copyright: (c) Eitan Chatav, 2017

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Create and drop view definitions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , ConstraintKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DerivingStrategies

17+ , FlexibleContexts

18+ , FlexibleInstances

19+ , GADTs

20+ , LambdaCase

21+ , MultiParamTypeClasses

22+ , OverloadedLabels

23+ , OverloadedStrings

24+ , RankNTypes

25+ , ScopedTypeVariables

26+ , TypeApplications

27+ , TypeInType

28+ , TypeOperators

29+ , UndecidableSuperClasses

30+#-}

31+

32+module Squeal.PostgreSQL.Definition.View

33+ ( createView

34+ , createOrReplaceView

35+ , dropView

36+ , dropViewIfExists

37+ ) where

38+

39+import GHC.TypeLits

40+

41+import Squeal.PostgreSQL.Alias

42+import Squeal.PostgreSQL.Definition

43+import Squeal.PostgreSQL.Query

44+import Squeal.PostgreSQL.Render

45+import Squeal.PostgreSQL.Schema

46+

47+-- $setup

48+-- >>> import Squeal.PostgreSQL

49+

50+{- | Create a view.

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

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

53+>>> :{

54+let

55+ definition :: Definition

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

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

58+ definition =

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

60+in printSQL definition

61+:}

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

63+-}

64+createView

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

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

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

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

69+createView alias query = UnsafeDefinition $

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

71+ <+> renderQuery query <> ";"

72+

73+createOrReplaceView

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

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

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

77+ -> Definition schemas (Alter sch (CreateOrReplace vw ('View view) schema) schemas)

78+createOrReplaceView alias query = UnsafeDefinition $

79+ "CREATE OR REPLACE VIEW" <+> renderSQL alias <+> "AS"

80+ <+> renderQuery query <> ";"

81+

82+-- | Drop a view.

83+--

84+-- >>> :{

85+-- let

86+-- definition :: Definition

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

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

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

90+-- definition = dropView #bc

91+-- in printSQL definition

92+-- :}

93+-- DROP VIEW "bc";

94+dropView

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

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

97+ -> Definition schemas (Alter sch (DropSchemum vw 'View schema) schemas)

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

99+

100+dropViewIfExists

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

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

103+ -> Definition schemas (Alter sch (DropIfExists vw schema) schemas)

104+dropViewIfExists vw = UnsafeDefinition $ "DROP VIEW IF EXISTS" <+> renderSQL vw <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+335−1624

@@ -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

@@ -31,546 +32,351 @@ 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+ , type (-->)

38+ , FunctionDB

5439 , 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

40+ , function

41+ , unsafeLeftOp

42+ , leftOp

43+ , unsafeRightOp

44+ , rightOp

45+ , Operator

46+ , OperatorDB

47+ , unsafeBinaryOp

48+ , binaryOp

49+ , FunctionVar

50+ , unsafeFunctionVar

51+ , type (--->)

52+ , FunctionNDB

53+ , unsafeFunctionN

54+ , functionN

55+ , PGSubset (..)

56+ , PGIntersect (..)

18057 -- * Re-export

18158 , (&)

182− , NP ((:*), Nil)

59+ , K (..)

60+ , unK

18361 ) where

18462

18563import Control.Category

18664import Control.DeepSeq

18765import Data.ByteString (ByteString)

188−import Data.ByteString.Lazy (toStrict)

18966import Data.Function ((&))

19067import Data.Semigroup hiding (All)

191−import qualified Data.Aeson as JSON

192−import Data.Ratio

19368import Data.String

194−import Data.Word

195−import Generics.SOP hiding (from)

69+import Generics.SOP hiding (All, from)

19670import GHC.OverloadedLabels

19771import GHC.TypeLits

72+import Numeric

19873import Prelude hiding (id, (.))

19974

20075import qualified GHC.Generics as GHC

20176

77+import Squeal.PostgreSQL.Alias

78+import Squeal.PostgreSQL.List

20279import Squeal.PostgreSQL.Render

20380import Squeal.PostgreSQL.Schema

20481

82+-- $setup

83+-- >>> import Squeal.PostgreSQL

84+

20585{-----------------------------------------

20686column expressions

20787-----------------------------------------}

20888

20989{- | `Expression`s are used in a variety of contexts,

210−such as in the target list of the `Squeal.PostgreSQL.Query.select` command,

90+such as in the target `Squeal.PostgreSQL.Query.List` of the

91+`Squeal.PostgreSQL.Query.select` command,

21192as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or

21293`Squeal.PostgreSQL.Manipulation.update`,

213−or in search `Condition`s in a number of commands.

94+or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.

21495

21596The expression syntax allows the calculation of

21697values from primitive expression using arithmetic, logical,

21798and other operations.

99+

100+The type parameters of `Expression` are

101+

102+* @outer :: @ `FromType`, the @from@ clauses of any outer queries in which

103+ the `Expression` is a correlated subquery expression;

104+* @commons :: @ `FromType`, the `Squeal.PostgreSQL.Query.CommonTableExpression`s

105+ that are in scope for the `Expression`;

106+* @grp :: @ `Grouping`, the `Grouping` of the @from@ clause which may limit

107+ which columns may be referenced by alias;

108+* @schemas :: @ `SchemasType`, the schemas of your database that are in

109+ scope for the `Expression`;

110+* @from :: @ `FromType`, the @from@ clause which the `Expression` may use

111+ to reference columns by alias;

112+* @ty :: @ `NullityType`, the type of the `Expression`.

218113-}

219114newtype Expression

220− (db :: DBType)

221− (from :: FromType)

222− (grouping :: Grouping)

115+ (outer :: FromType)

116+ (commons :: FromType)

117+ (grp :: Grouping)

118+ (schemas :: SchemasType)

223119 (params :: [NullityType])

120+ (from :: FromType)

224121 (ty :: NullityType)

225122 = UnsafeExpression { renderExpression :: ByteString }

226123 deriving (GHC.Generic,Show,Eq,Ord,NFData)

227−

228−instance RenderSQL (Expression db from grouping params ty) where

124+instance RenderSQL (Expression outer commons grp schemas params from ty) where

229125 renderSQL = renderExpression

230126

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.

127+-- | An `Expr` is a closed `Expression`.

128+-- It is a F@RankNType@ but don't be scared.

129+-- Think of it as an expression which sees no

130+-- namespaces, so you can't use parameters

131+-- or alias references. It can be used as

132+-- a simple piece of more complex `Expression`s.

133+type Expr x

134+ = forall outer commons grp schemas params from

135+ . Expression outer commons grp schemas params from x

136+ -- ^ cannot reference aliases

137+

138+-- | A @RankNType@ for binary operators.

139+type Operator x1 x2 y

140+ = forall outer commons grp schemas params from

141+ . Expression outer commons grp schemas params from x1

142+ -- ^ left input

143+ -> Expression outer commons grp schemas params from x2

144+ -- ^ right input

145+ -> Expression outer commons grp schemas params from y

146+ -- ^ output

147+

148+type OperatorDB schemas x1 x2 y

149+ = forall outer commons grp params from

150+ . Expression outer commons grp schemas params from x1

151+ -- ^ left input

152+ -> Expression outer commons grp schemas params from x2

153+ -- ^ right input

154+ -> Expression outer commons grp schemas params from y

155+ -- ^ output

156+

157+-- | A @RankNType@ for functions with a single argument.

158+-- These could be either function calls or unary operators.

159+-- This is a subtype of the usual Haskell function type `Prelude.->`,

160+-- indeed a subcategory as it is closed under the usual

161+-- `Prelude..` and `Prelude.id`.

162+type (-->) x y

163+ = forall outer commons grp schemas params from

164+ . Expression outer commons grp schemas params from x

165+ -- ^ input

166+ -> Expression outer commons grp schemas params from y

167+ -- ^ output

168+

169+type FunctionDB schemas x y

170+ = forall outer commons grp params from

171+ . Expression outer commons grp schemas params from x

172+ -- ^ input

173+ -> Expression outer commons grp schemas params from y

174+ -- ^ output

175+

176+{- | A @RankNType@ for functions with a fixed-length list of heterogeneous arguments.

177+Use the `*:` operator to end your argument lists, like so.

178+

179+>>> printSQL (unsafeFunctionN "fun" (true :* false :* localTime *: true))

180+fun(TRUE, FALSE, LOCALTIME, TRUE)

238181-}

239−class KnownNat n => HasParameter

240− (n :: Nat)

241− (params :: [NullityType])

242− (ty :: NullityType)

243− | n params -> ty where

244− -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.

245− --

246− -- >>> let expr = parameter @1 int4 :: Expression (DBof schemas) from grp '[ 'Null 'PGint4] ('Null 'PGint4)

247− -- >>> printSQL expr

248− -- ($1 :: int4)

249− parameter

250− :: TypeExpression schemas ty

251− -> Expression (commons :=> schemas) from grouping params ty

252− parameter ty = UnsafeExpression $ parenthesized $

253− "$" <> renderNat @n <+> "::"

254− <+> renderTypeExpression ty

255−instance {-# OVERLAPPING #-} HasParameter 1 (ty1:tys) ty1

256−instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)

257− => HasParameter n (ty' : params) ty

258−

259−-- | `param` takes a `Nat` using type application and for basic types,

260−-- infers a `TypeExpression`.

261−--

262−-- >>> let expr = param @1 :: Expression (commons :=> schemas) from grp '[ 'Null 'PGint4] ('Null 'PGint4)

263−-- >>> printSQL expr

264−-- ($1 :: int4)

265−param

266− :: forall n db commons schemas params from grouping ty

267− . (db ~ (commons :=> schemas), PGTyped schemas ty, HasParameter n params ty)

268− => Expression db from grouping params ty -- ^ param

269−param = parameter @n (pgtype @schemas)

270−

271−instance (HasUnique table from columns, Has column columns ty)

272− => IsLabel column (Expression db from 'Ungrouped params ty) where

273− fromLabel = UnsafeExpression $ renderAlias (Alias @column)

274−instance (HasUnique table from columns, Has column columns ty)

275− => IsLabel column

276− (Aliased (Expression db from 'Ungrouped params) (column ::: ty)) where

277− fromLabel = fromLabel @column `As` Alias @column

278−instance (HasUnique table from columns, Has column columns ty)

279− => IsLabel column

280− (NP (Aliased (Expression db from 'Ungrouped params)) '[column ::: ty]) where

281− fromLabel = fromLabel @column :* Nil

282−

283−instance (Has table from columns, Has column columns ty)

284− => IsQualified table column (Expression db from 'Ungrouped params ty) where

285− table ! column = UnsafeExpression $

286− renderAlias table <> "." <> renderAlias column

287−instance (Has table from columns, Has column columns ty)

288− => IsQualified table column

289− (Aliased (Expression db from 'Ungrouped params) (column ::: ty)) where

290− table ! column = table ! column `As` column

291−instance (Has table from columns, Has column columns ty)

292− => IsQualified table column

293− (NP (Aliased (Expression db from 'Ungrouped params)) '[column ::: ty]) where

294− table ! column = table ! column :* Nil

182+type (--->) xs y

183+ = forall outer commons grp schemas params from

184+ . NP (Expression outer commons grp schemas params from) xs

185+ -- ^ inputs

186+ -> Expression outer commons grp schemas params from y

187+ -- ^ output

188+

189+type FunctionNDB schemas xs y

190+ = forall outer commons grp params from

191+ . NP (Expression outer commons grp schemas params from) xs

192+ -- ^ inputs

193+ -> Expression outer commons grp schemas params from y

194+ -- ^ output

195+

196+{- | A @RankNType@ for functions with a variable-length list of

197+homogeneous arguments and at least 1 more argument.

198+-}

199+type FunctionVar x0 x1 y

200+ = forall outer commons grp schemas params from

201+ . [Expression outer commons grp schemas params from x0]

202+ -- ^ inputs

203+ -> Expression outer commons grp schemas params from x1

204+ -- ^ must have at least 1 input

205+ -> Expression outer commons grp schemas params from y

206+ -- ^ output

207+

208+{- | >>> printSQL (unsafeFunctionVar "greatest" [true, null_] false)

209+greatest(TRUE, NULL, FALSE)

210+-}

211+unsafeFunctionVar :: ByteString -> FunctionVar x0 x1 y

212+unsafeFunctionVar fun xs x = UnsafeExpression $ fun <> parenthesized

213+ (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)

214+

215+instance (HasUnique tab (Join outer from) row, Has col row ty)

216+ => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where

217+ fromLabel = UnsafeExpression $ renderSQL (Alias @col)

218+instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])

219+ => IsLabel col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where

220+ fromLabel = fromLabel @col :* Nil

221+instance (HasUnique tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))

222+ => IsLabel col

223+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where

224+ fromLabel = fromLabel @col `As` Alias

225+instance (HasUnique tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])

226+ => IsLabel col

227+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where

228+ fromLabel = fromLabel @col :* Nil

229+

230+instance (Has tab (Join outer from) row, Has col row ty)

231+ => IsQualified tab col (Expression outer commons 'Ungrouped schemas params from ty) where

232+ tab ! col = UnsafeExpression $

233+ renderSQL tab <> "." <> renderSQL col

234+instance (Has tab (Join outer from) row, Has col row ty, tys ~ '[ty])

235+ => IsQualified tab col (NP (Expression outer commons 'Ungrouped schemas params from) tys) where

236+ tab ! col = tab ! col :* Nil

237+instance (Has tab (Join outer from) row, Has col row ty, column ~ (col ::: ty))

238+ => IsQualified tab col

239+ (Aliased (Expression outer commons 'Ungrouped schemas params from) column) where

240+ tab ! col = tab ! col `As` col

241+instance (Has tab (Join outer from) row, Has col row ty, columns ~ '[col ::: ty])

242+ => IsQualified tab col

243+ (NP (Aliased (Expression outer commons 'Ungrouped schemas params from)) columns) where

244+ tab ! col = tab ! col :* Nil

295245

296246instance

297− ( HasUnique table from columns

298− , Has column columns ty

299− , GroupedBy table column bys

300− ) => IsLabel column

301− (Expression db from ('Grouped bys) params ty) where

302− fromLabel = UnsafeExpression $ renderAlias (Alias @column)

247+ ( HasUnique tab (Join outer from) row

248+ , Has col row ty

249+ , GroupedBy tab col bys

250+ ) => IsLabel col

251+ (Expression outer commons ('Grouped bys) schemas params from ty) where

252+ fromLabel = UnsafeExpression $ renderSQL (Alias @col)

303253instance

304− ( HasUnique table from columns

305− , Has column columns ty

306− , GroupedBy table column bys

307− ) => IsLabel column

308− ( Aliased (Expression db from ('Grouped bys) params)

309− (column ::: ty) ) where

310− fromLabel = fromLabel @column `As` Alias @column

254+ ( HasUnique tab (Join outer from) row

255+ , Has col row ty

256+ , GroupedBy tab col bys

257+ , tys ~ '[ty]

258+ ) => IsLabel col

259+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

260+ fromLabel = fromLabel @col :* Nil

311261instance

312− ( HasUnique table from columns

313− , Has column columns ty

314− , GroupedBy table column bys

315− ) => IsLabel column

316− ( NP (Aliased (Expression db from ('Grouped bys) params))

317− '[column ::: ty] ) where

318− fromLabel = fromLabel @column :* Nil

262+ ( HasUnique tab (Join outer from) row

263+ , Has col row ty

264+ , GroupedBy tab col bys

265+ , column ~ (col ::: ty)

266+ ) => IsLabel col

267+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where

268+ fromLabel = fromLabel @col `As` Alias

269+instance

270+ ( HasUnique tab (Join outer from) row

271+ , Has col row ty

272+ , GroupedBy tab col bys

273+ , columns ~ '[col ::: ty]

274+ ) => IsLabel col

275+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where

276+ fromLabel = fromLabel @col :* Nil

319277

320278instance

321− ( Has table from columns

322− , Has column columns ty

323− , GroupedBy table column bys

324− ) => IsQualified table column

325− (Expression db from ('Grouped bys) params ty) where

326− table ! column = UnsafeExpression $

327− renderAlias table <> "." <> renderAlias column

279+ ( Has tab (Join outer from) row

280+ , Has col row ty

281+ , GroupedBy tab col bys

282+ ) => IsQualified tab col

283+ (Expression outer commons ('Grouped bys) schemas params from ty) where

284+ tab ! col = UnsafeExpression $

285+ renderSQL tab <> "." <> renderSQL col

328286instance

329− ( Has table from columns

330− , Has column columns ty

331− , GroupedBy table column bys

332− ) => IsQualified table column

333− (Aliased (Expression db from ('Grouped bys) params)

334− (column ::: ty)) where

335− table ! column = table ! column `As` column

287+ ( Has tab (Join outer from) row

288+ , Has col row ty

289+ , GroupedBy tab col bys

290+ , tys ~ '[ty]

291+ ) => IsQualified tab col

292+ (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

293+ tab ! col = tab ! col :* Nil

336294instance

337− ( Has table from columns

338− , Has column columns ty

339− , GroupedBy table column bys

340− ) => IsQualified table column

341− ( NP (Aliased (Expression db from ('Grouped bys) params))

342− '[column ::: ty]) where

343− table ! column = table ! column :* Nil

344−

345−-- | analagous to `Nothing`

346−--

347−-- >>> printSQL null_

348−-- NULL

349−null_ :: Expression db rels grouping params ('Null ty)

350−null_ = UnsafeExpression "NULL"

351−

352−-- | analagous to `Just`

353−--

354−-- >>> printSQL $ notNull true

355−-- TRUE

356−notNull

357− :: Expression db rels grouping params ('NotNull ty)

358− -> Expression db rels grouping params ('Null ty)

359−notNull = UnsafeExpression . renderExpression

360−

361−-- | return the leftmost value which is not NULL

362−--

363−-- >>> printSQL $ coalesce [null_, true] false

364−-- COALESCE(NULL, TRUE, FALSE)

365−coalesce

366− :: [Expression db from grouping params ('Null ty)]

367− -- ^ @NULL@s may be present

368− -> Expression db from grouping params ('NotNull ty)

369− -- ^ @NULL@ is absent

370− -> Expression db from grouping params ('NotNull ty)

371−coalesce nullxs notNullx = UnsafeExpression $

372− "COALESCE" <> parenthesized (commaSeparated

373− ((renderExpression <$> nullxs) <> [renderExpression notNullx]))

374−

375−-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@

376−--

377−-- >>> printSQL $ fromNull true null_

378−-- COALESCE(NULL, TRUE)

379−fromNull

380− :: Expression db from grouping params ('NotNull ty)

381− -- ^ what to convert @NULL@ to

382− -> Expression db from grouping params ('Null ty)

383− -> Expression db from grouping params ('NotNull ty)

384−fromNull notNullx nullx = coalesce [nullx] notNullx

385−

386−-- | >>> printSQL $ null_ & isNull

387−-- NULL IS NULL

388−isNull

389− :: Expression db from grouping params ('Null ty)

390− -- ^ possibly @NULL@

391− -> Condition db from grouping params

392−isNull x = UnsafeExpression $ renderExpression x <+> "IS NULL"

393−

394−-- | >>> printSQL $ null_ & isNotNull

395−-- NULL IS NOT NULL

396−isNotNull

397− :: Expression db from grouping params ('Null ty)

398− -- ^ possibly @NULL@

399− -> Condition db from grouping params

400−isNotNull x = UnsafeExpression $ renderExpression x <+> "IS NOT NULL"

401−

402−-- | analagous to `maybe` using @IS NULL@

403−--

404−-- >>> printSQL $ matchNull true not_ null_

405−-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END

406−matchNull

407− :: Expression db from grouping params (nullty)

408− -- ^ what to convert @NULL@ to

409− -> ( Expression db from grouping params ('NotNull ty)

410− -> Expression db from grouping params (nullty) )

411− -- ^ function to perform when @NULL@ is absent

412− -> Expression db from grouping params ('Null ty)

413− -> Expression db from grouping params (nullty)

414−matchNull y f x = ifThenElse (isNull x) y

415− (f (UnsafeExpression (renderExpression x)))

416−

417−{-| right inverse to `fromNull`, if its arguments are equal then

418−`nullIf` gives @NULL@.

419−

420−>>> :set -XTypeApplications -XDataKinds

421−>>> let expr = nullIf false (param @1) :: Expression (commons :=> schema) from grp '[ 'NotNull 'PGbool] ('Null 'PGbool)

422−>>> printSQL expr

423−NULL IF (FALSE, ($1 :: bool))

424−-}

425−nullIf

426− :: Expression db from grouping params ('NotNull ty)

427− -- ^ @NULL@ is absent

428− -> Expression db from grouping params ('NotNull ty)

429− -- ^ @NULL@ is absent

430− -> Expression db from grouping params ('Null ty)

431−nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized

432− (renderExpression x <> ", " <> renderExpression y)

433−

434−-- | >>> printSQL $ array [null_, false, true]

435−-- ARRAY[NULL, FALSE, TRUE]

436−array

437− :: [Expression db from grouping params ty]

438− -- ^ array elements

439− -> Expression db from grouping params (nullity ('PGvararray ty))

440−array xs = UnsafeExpression $

441− "ARRAY[" <> commaSeparated (renderExpression <$> xs) <> "]"

442−

443−-- | >>> printSQL $ array [null_, false, true] & index 2

444−-- (ARRAY[NULL, FALSE, TRUE])[2]

445−index

446− :: Word64 -- ^ index

447− -> Expression db from grouping params (nullity ('PGvararray ty)) -- ^ array

448− -> Expression db from grouping params (NullifyType ty)

449−index n expr = UnsafeExpression $

450− parenthesized (renderExpression expr) <> "[" <> fromString (show n) <> "]"

295+ ( Has tab (Join outer from) row

296+ , Has col row ty

297+ , GroupedBy tab col bys

298+ , column ~ (col ::: ty)

299+ ) => IsQualified tab col

300+ (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where

301+ tab ! col = tab ! col `As` col

302+instance

303+ ( Has tab (Join outer from) row

304+ , Has col row ty

305+ , GroupedBy tab col bys

306+ , columns ~ '[col ::: ty]

307+ ) => IsQualified tab col

308+ (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where

309+ tab ! col = tab ! col :* Nil

451310

452311instance (KnownSymbol label, label `In` labels) => IsPGlabel label

453− (Expression db from grouping params (nullity ('PGenum labels))) where

454− label = UnsafeExpression $ renderLabel (PGlabel @label)

455−

456−-- | A row constructor is an expression that builds a row value

457−-- (also called a composite value) using values for its member fields.

458−--

459−-- >>> :{

460−-- type Complex = 'PGcomposite

461−-- '[ "real" ::: 'NotNull 'PGfloat8

462−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

463−-- :}

464−--

465−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression db from grp params ('NotNull Complex)

466−-- >>> printSQL i

467−-- ROW(0, 1)

468−row

469− :: SListI row

470− => NP (Aliased (Expression db from grouping params)) row

471− -- ^ zero or more expressions for the row field values

472− -> Expression db from grouping params (nullity ('PGcomposite row))

473−row exprs = UnsafeExpression $ "ROW" <> parenthesized

474− (renderCommaSeparated (\ (expr `As` _) -> renderExpression expr) exprs)

475−

476−-- | >>> :{

477−-- type Complex = 'PGcomposite

478−-- '[ "real" ::: 'NotNull 'PGfloat8

479−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

480−-- type Schema = '["complex" ::: 'Typedef Complex]

481−-- type DB = DBof (Public Schema)

482−-- :}

483−--

484−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression DB from grp params ('NotNull Complex)

485−-- >>> printSQL $ i & field #complex #imaginary

486−-- (ROW(0, 1)::"complex")."imaginary"

487−field

488− :: ( Has sch schemas schema

489− , Has tydef schema ('Typedef ('PGcomposite row))

490− , Has field row ty)

491− => QualifiedAlias sch tydef -- ^ row type

492− -> Alias field -- ^ field name

493− -> Expression (commons :=> schemas) from grouping params ('NotNull ('PGcomposite row))

494− -> Expression (commons :=> schemas) from grouping params ty

495−field td fld expr = UnsafeExpression $

496− parenthesized (renderExpression expr <> "::" <> renderQualifiedAlias td)

497− <> "." <> renderAlias fld

498−

499−instance Semigroup

500− (Expression db from grouping params (nullity ('PGvararray ty))) where

501− (<>) = unsafeBinaryOp "||"

502−

503−instance Monoid

504− (Expression db from grouping params (nullity ('PGvararray ty))) where

505− mempty = array []

506− mappend = (<>)

507−

508−-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression (commons :=> schemas) rels grp '[ 'NotNull 'PGtimestamptz] ('NotNull 'PGtimestamptz)

509−-- >>> printSQL expr

510−-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))

511−greatest

512− :: Expression db from grouping params (nullty)

513− -- ^ needs at least 1 argument

514− -> [Expression db from grouping params (nullty)]

515− -- ^ or more

516− -> Expression db from grouping params (nullty)

517−greatest x xs = UnsafeExpression $ "GREATEST("

518− <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

519−

520−-- | >>> printSQL $ least currentTimestamp [null_]

521−-- LEAST(CURRENT_TIMESTAMP, NULL)

522−least

523− :: Expression db from grouping params (nullty)

524− -- ^ needs at least 1 argument

525− -> [Expression db from grouping params (nullty)]

526− -- ^ or more

527− -> Expression db from grouping params (nullty)

528−least x xs = UnsafeExpression $ "LEAST("

529− <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

312+ (Expression outer commons grp schemas params from (null ('PGenum labels))) where

313+ label = UnsafeExpression $ renderSQL (PGlabel @label)

530314

531315-- | >>> printSQL $ unsafeBinaryOp "OR" true false

532316-- (TRUE OR FALSE)

533−unsafeBinaryOp

534− :: ByteString

535− -- ^ operator

536− -> Expression db from grouping params (ty0)

537− -> Expression db from grouping params (ty1)

538− -> Expression db from grouping params (ty2)

317+unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2

539318unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $

540− renderExpression x <+> op <+> renderExpression y

319+ renderSQL x <+> op <+> renderSQL y

541320

542−-- | >>> printSQL $ unsafeUnaryOp "NOT" true

321+binaryOp

322+ :: forall op sch schemas schema x y z.

323+ ( Has sch schemas schema

324+ , Has op schema ('Operator ('BinaryOp x y z)) )

325+ => OperatorDB schemas x y z

326+binaryOp = unsafeBinaryOp $ renderSymbol @op

327+

328+-- | >>> printSQL $ unsafeLeftOp "NOT" true

543329-- (NOT TRUE)

544−unsafeUnaryOp

545− :: ByteString

546− -- ^ operator

547− -> Expression db from grouping params (ty0)

548− -> Expression db from grouping params (ty1)

549−unsafeUnaryOp op x = UnsafeExpression $ parenthesized $

550− op <+> renderExpression x

330+unsafeLeftOp :: ByteString -> x --> y

331+unsafeLeftOp op x = UnsafeExpression $ parenthesized $ op <+> renderSQL x

332+

333+leftOp

334+ :: forall op sch schemas schema x y.

335+ ( Has sch schemas schema

336+ , Has op schema ('Operator ('LeftOp x y)) )

337+ => FunctionDB schemas x y

338+leftOp = unsafeLeftOp $ renderSymbol @op

339+

340+-- | >>> printSQL $ true & unsafeRightOp "IS NOT TRUE"

341+-- (TRUE IS NOT TRUE)

342+unsafeRightOp :: ByteString -> x --> y

343+unsafeRightOp op x = UnsafeExpression $ parenthesized $ renderSQL x <+> op

344+

345+rightOp

346+ :: forall op sch schemas schema x y.

347+ ( Has sch schemas schema

348+ , Has op schema ('Operator ('RightOp x y)) )

349+ => FunctionDB schemas x y

350+rightOp = unsafeRightOp $ renderSymbol @op

551351

552352-- | >>> printSQL $ unsafeFunction "f" true

553353-- f(TRUE)

554−unsafeFunction

555− :: ByteString

556− -- ^ function

557− -> Expression db from grouping params (xty)

558− -> Expression db from grouping params (yty)

354+unsafeFunction :: ByteString -> x --> y

559355unsafeFunction fun x = UnsafeExpression $

560− fun <> parenthesized (renderExpression x)

356+ fun <> parenthesized (renderSQL x)

357+

358+function

359+ :: (Has sch schemas schema, Has fun schema ('Function ('[x] :=> 'Returns y)))

360+ => QualifiedAlias sch fun

361+ -> FunctionDB schemas x y

362+function = unsafeFunction . renderSQL

561363

562−-- | Helper for defining variadic functions.

563−unsafeVariadicFunction

564− :: SListI elems

565− => ByteString

566− -- ^ function

567− -> NP (Expression db from grouping params) elems

568− -> Expression db from grouping params ret

569−unsafeVariadicFunction fun x = UnsafeExpression $

570− fun <> parenthesized (commaSeparated (hcollapse (hmap (K . renderExpression) x)))

364+-- | >>> printSQL $ unsafeFunctionN "f" (currentTime :* localTimestamp :* false *: literal 'a')

365+-- f(CURRENT_TIME, LOCALTIMESTAMP, FALSE, E'a')

366+unsafeFunctionN :: SListI xs => ByteString -> xs ---> y

367+unsafeFunctionN fun xs = UnsafeExpression $

368+ fun <> parenthesized (renderCommaSeparated renderSQL xs)

369+

370+functionN

371+ :: ( Has sch schemas schema

372+ , Has fun schema ('Function (xs :=> 'Returns y))

373+ , SListI xs )

374+ => QualifiedAlias sch fun

375+ -> FunctionNDB schemas xs y

376+functionN = unsafeFunctionN . renderSQL

571377

572378instance ty `In` PGNum

573− => Num (Expression db from grouping params (nullity ty)) where

379+ => Num (Expression outer commons grp schemas params from (null ty)) where

574380 (+) = unsafeBinaryOp "+"

575381 (-) = unsafeBinaryOp "-"

576382 (*) = unsafeBinaryOp "*"

@@ -582,18 +388,23 @@ instance ty `In` PGNum

582388 . show

583389

584390instance (ty `In` PGNum, ty `In` PGFloating) => Fractional

585− (Expression db from grouping params (nullity ty)) where

391+ (Expression outer commons grp schemas params from (null ty)) where

586392 (/) = unsafeBinaryOp "/"

587− fromRational x = fromInteger (numerator x) / fromInteger (denominator x)

393+ fromRational

394+ = UnsafeExpression

395+ . fromString

396+ . ($ "")

397+ . showFFloat Nothing

398+ . fromRat @Double

588399

589400instance (ty `In` PGNum, ty `In` PGFloating) => Floating

590− (Expression db from grouping params (nullity ty)) where

401+ (Expression outer commons grp schemas params from (null ty)) where

591402 pi = UnsafeExpression "pi()"

592403 exp = unsafeFunction "exp"

593404 log = unsafeFunction "ln"

594405 sqrt = unsafeFunction "sqrt"

595406 b ** x = UnsafeExpression $

596− "power(" <> renderExpression b <> ", " <> renderExpression x <> ")"

407+ "power(" <> renderSQL b <> ", " <> renderSQL x <> ")"

597408 logBase b y = log y / log b

598409 sin = unsafeFunction "sin"

599410 cos = unsafeFunction "cos"

@@ -608,1154 +419,54 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating

608419 acosh x = log (x + sqrt (x*x - 1))

609420 atanh x = log ((1 + x) / (1 - x)) / 2

610421

611−-- | >>> :{

612−-- let

613−-- expression :: Expression db from grouping params (nullity 'PGfloat4)

614−-- expression = atan2_ pi 2

615−-- in printSQL expression

616−-- :}

617−-- atan2(pi(), 2)

618−atan2_

619− :: float `In` PGFloating

620− => Expression db from grouping params (nullity float)

621− -- ^ numerator

622− -> Expression db from grouping params (nullity float)

623− -- ^ denominator

624− -> Expression db from grouping params (nullity float)

625−atan2_ y x = UnsafeExpression $

626− "atan2(" <> renderExpression y <> ", " <> renderExpression x <> ")"

627−

628−-- When a `cast` is applied to an `Expression` of a known type, it

629−-- represents a run-time type conversion. The cast will succeed only if a

630−-- suitable type conversion operation has been defined.

631−--

632−-- | >>> printSQL $ true & cast int4

633−-- (TRUE :: int4)

634−cast

635− :: TypeExpression schemas ty1

636− -- ^ type to cast as

637− -> Expression (commons :=> schemas) from grouping params ty0

638− -- ^ value to convert

639− -> Expression (commons :=> schemas) from grouping params ty1

640−cast ty x = UnsafeExpression $ parenthesized $

641− renderExpression x <+> "::" <+> renderTypeExpression ty

642−

643−-- | integer division, truncates the result

644−--

645−-- >>> :{

646−-- let

647−-- expression :: Expression db from grouping params (nullity 'PGint2)

648−-- expression = 5 `quot_` 2

649−-- in printSQL expression

650−-- :}

651−-- (5 / 2)

652−quot_

653− :: int `In` PGIntegral

654− => Expression db from grouping params (nullity int)

655− -- ^ numerator

656− -> Expression db from grouping params (nullity int)

657− -- ^ denominator

658− -> Expression db from grouping params (nullity int)

659−quot_ = unsafeBinaryOp "/"

660−

661−-- | remainder upon integer division

662−--

663−-- >>> :{

664−-- let

665−-- expression :: Expression db from grouping params (nullity 'PGint2)

666−-- expression = 5 `rem_` 2

667−-- in printSQL expression

668−-- :}

669−-- (5 % 2)

670−rem_

671− :: int `In` PGIntegral

672− => Expression db from grouping params (nullity int)

673− -- ^ numerator

674− -> Expression db from grouping params (nullity int)

675− -- ^ denominator

676− -> Expression db from grouping params (nullity int)

677−rem_ = unsafeBinaryOp "%"

678−

679−-- | >>> :{

680−-- let

681−-- expression :: Expression db from grouping params (nullity 'PGfloat4)

682−-- expression = trunc pi

683−-- in printSQL expression

684−-- :}

685−-- trunc(pi())

686−trunc

687− :: frac `In` PGFloating

688− => Expression db from grouping params (nullity frac)

689− -- ^ fractional number

690− -> Expression db from grouping params (nullity frac)

691−trunc = unsafeFunction "trunc"

692−

693−-- | >>> :{

694−-- let

695−-- expression :: Expression db from grouping params (nullity 'PGfloat4)

696−-- expression = round_ pi

697−-- in printSQL expression

698−-- :}

699−-- round(pi())

700−round_

701− :: frac `In` PGFloating

702− => Expression db from grouping params (nullity frac)

703− -- ^ fractional number

704− -> Expression db from grouping params (nullity frac)

705−round_ = unsafeFunction "round"

706−

707−-- | >>> :{

708−-- let

709−-- expression :: Expression db from grouping params (nullity 'PGfloat4)

710−-- expression = ceiling_ pi

711−-- in printSQL expression

712−-- :}

713−-- ceiling(pi())

714−ceiling_

715− :: frac `In` PGFloating

716− => Expression db from grouping params (nullity frac)

717− -- ^ fractional number

718− -> Expression db from grouping params (nullity frac)

719−ceiling_ = unsafeFunction "ceiling"

720−

721−-- | A `Condition` is an `Expression`, which can evaluate

722−-- to `true`, `false` or `null_`. This is because SQL uses

723−-- a three valued logic.

724−type Condition db from grouping params =

725− Expression db from grouping params ('Null 'PGbool)

726−

727−-- | >>> printSQL true

728−-- TRUE

729−true :: Expression db from grouping params (nullity 'PGbool)

730−true = UnsafeExpression "TRUE"

731−

732−-- | >>> printSQL false

733−-- FALSE

734−false :: Expression db from grouping params (nullity 'PGbool)

735−false = UnsafeExpression "FALSE"

736−

737−-- | >>> printSQL $ not_ true

738−-- (NOT TRUE)

739−not_

740− :: Expression db from grouping params (nullity 'PGbool)

741− -> Expression db from grouping params (nullity 'PGbool)

742−not_ = unsafeUnaryOp "NOT"

743−

744−-- | >>> printSQL $ true .&& false

745−-- (TRUE AND FALSE)

746−(.&&)

747− :: Expression db from grouping params (nullity 'PGbool)

748− -> Expression db from grouping params (nullity 'PGbool)

749− -> Expression db from grouping params (nullity 'PGbool)

750−infixr 3 .&&

751−(.&&) = unsafeBinaryOp "AND"

752−

753−-- | >>> printSQL $ true .|| false

754−-- (TRUE OR FALSE)

755−(.||)

756− :: Expression db from grouping params (nullity 'PGbool)

757− -> Expression db from grouping params (nullity 'PGbool)

758− -> Expression db from grouping params (nullity 'PGbool)

759−infixr 2 .||

760−(.||) = unsafeBinaryOp "OR"

761−

762−-- | >>> :{

763−-- let

764−-- expression :: Expression db from grouping params (nullity 'PGint2)

765−-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3

766−-- in printSQL expression

767−-- :}

768−-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END

769−caseWhenThenElse

770− :: [ ( Condition db from grouping params

771− , Expression db from grouping params ty

772− ) ]

773− -- ^ whens and thens

774− -> Expression db from grouping params ty

775− -- ^ else

776− -> Expression db from grouping params ty

777−caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat

778− [ "CASE"

779− , mconcat

780− [ mconcat

781− [ " WHEN ", renderExpression when_

782− , " THEN ", renderExpression then_

783− ]

784− | (when_,then_) <- whenThens

785− ]

786− , " ELSE ", renderExpression else_

787− , " END"

788− ]

789−

790−-- | >>> :{

791−-- let

792−-- expression :: Expression db from grouping params (nullity 'PGint2)

793−-- expression = ifThenElse true 1 0

794−-- in printSQL expression

795−-- :}

796−-- CASE WHEN TRUE THEN 1 ELSE 0 END

797−ifThenElse

798− :: Condition db from grouping params

799− -> Expression db from grouping params ty -- ^ then

800− -> Expression db from grouping params ty -- ^ else

801− -> Expression db from grouping params ty

802−ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_

803−

804−-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`

805−-- will produce @NULL@s if one of their arguments is @NULL@.

806−--

807−-- >>> printSQL $ true .== null_

808−-- (TRUE = NULL)

809−(.==)

810− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

811− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

812− -> Condition db from grouping params

813−(.==) = unsafeBinaryOp "="

814−infix 4 .==

815−

816−-- | >>> printSQL $ true ./= null_

817−-- (TRUE <> NULL)

818−(./=)

819− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

820− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

821− -> Condition db from grouping params

822−(./=) = unsafeBinaryOp "<>"

823−infix 4 ./=

824−

825−-- | >>> printSQL $ true .>= null_

826−-- (TRUE >= NULL)

827−(.>=)

828− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

829− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

830− -> Condition db from grouping params

831−(.>=) = unsafeBinaryOp ">="

832−infix 4 .>=

833−

834−-- | >>> printSQL $ true .< null_

835−-- (TRUE < NULL)

836−(.<)

837− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

838− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

839− -> Condition db from grouping params

840−(.<) = unsafeBinaryOp "<"

841−infix 4 .<

842−

843−-- | >>> printSQL $ true .<= null_

844−-- (TRUE <= NULL)

845−(.<=)

846− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

847− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

848− -> Condition db from grouping params

849−(.<=) = unsafeBinaryOp "<="

850−infix 4 .<=

851−

852−-- | >>> printSQL $ true .> null_

853−-- (TRUE > NULL)

854−(.>)

855− :: Expression db from grouping params (nullity0 ty) -- ^ lhs

856− -> Expression db from grouping params (nullity1 ty) -- ^ rhs

857− -> Condition db from grouping params

858−(.>) = unsafeBinaryOp ">"

859−infix 4 .>

860−

861−-- | >>> printSQL currentDate

862−-- CURRENT_DATE

863−currentDate

864− :: Expression db from grouping params (nullity 'PGdate)

865−currentDate = UnsafeExpression "CURRENT_DATE"

866−

867−-- | >>> printSQL currentTime

868−-- CURRENT_TIME

869−currentTime

870− :: Expression db from grouping params (nullity 'PGtimetz)

871−currentTime = UnsafeExpression "CURRENT_TIME"

872−

873−-- | >>> printSQL currentTimestamp

874−-- CURRENT_TIMESTAMP

875−currentTimestamp

876− :: Expression db from grouping params (nullity 'PGtimestamptz)

877−currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

878−

879−-- | >>> printSQL localTime

880−-- LOCALTIME

881−localTime

882− :: Expression db from grouping params (nullity 'PGtime)

883−localTime = UnsafeExpression "LOCALTIME"

884−

885−-- | >>> printSQL localTimestamp

886−-- LOCALTIMESTAMP

887−localTimestamp

888− :: Expression db from grouping params (nullity 'PGtimestamp)

889−localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

890−

891−{-----------------------------------------

892−text

893−-----------------------------------------}

422+-- | Contained by operators

423+class PGSubset ty where

424+ (@>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

425+ (@>) = unsafeBinaryOp "@>"

426+ (<@) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

427+ (<@) = unsafeBinaryOp "<@"

428+instance PGSubset 'PGjsonb

429+instance PGSubset 'PGtsquery

430+instance PGSubset ('PGvararray ty)

431+instance PGSubset ('PGrange ty)

432+

433+class PGIntersect ty where

434+ (@&&) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

435+ (@&&) = unsafeBinaryOp "&&"

436+instance PGIntersect ('PGvararray ty)

437+instance PGIntersect ('PGrange ty)

894438

895439instance IsString

896− (Expression db from grouping params (nullity 'PGtext)) where

440+ (Expression outer commons grp schemas params from (null 'PGtext)) where

897441 fromString str = UnsafeExpression $

898442 "E\'" <> fromString (escape =<< str) <> "\'"

899− where

900− escape = \case

901− '\NUL' -> "\\0"

902− '\'' -> "''"

903− '"' -> "\\\""

904− '\b' -> "\\b"

905− '\n' -> "\\n"

906− '\r' -> "\\r"

907− '\t' -> "\\t"

908− '\\' -> "\\\\"

909− c -> [c]

443+instance IsString

444+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

445+ fromString str = UnsafeExpression . parenthesized . (<> " :: tsvector") $

446+ "E\'" <> fromString (escape =<< str) <> "\'"

447+instance IsString

448+ (Expression outer commons grp schemas params from (null 'PGtsquery)) where

449+ fromString str = UnsafeExpression . parenthesized . (<> " :: tsquery") $

450+ "E\'" <> fromString (escape =<< str) <> "\'"

910451

911452instance Semigroup

912− (Expression db from grouping params (nullity 'PGtext)) where

453+ (Expression outer commons grp schemas params from (null ('PGvararray ty))) where

454+ (<>) = unsafeBinaryOp "||"

455+instance Semigroup

456+ (Expression outer commons grp schemas params from (null 'PGjsonb)) where

457+ (<>) = unsafeBinaryOp "||"

458+instance Semigroup

459+ (Expression outer commons grp schemas params from (null 'PGtext)) where

460+ (<>) = unsafeBinaryOp "||"

461+instance Semigroup

462+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

913463 (<>) = unsafeBinaryOp "||"

914464

915465instance Monoid

916− (Expression db from grouping params (nullity 'PGtext)) where

466+ (Expression outer commons grp schemas params from (null 'PGtext)) where

467+ mempty = fromString ""

468+ mappend = (<>)

469+instance Monoid

470+ (Expression outer commons grp schemas params from (null 'PGtsvector)) where

917471 mempty = fromString ""

918472 mappend = (<>)

919−

920−-- | >>> printSQL $ lower "ARRRGGG"

921−-- lower(E'ARRRGGG')

922−lower

923− :: Expression db from grouping params (nullity 'PGtext)

924− -- ^ string to lower case

925− -> Expression db from grouping params (nullity 'PGtext)

926−lower = unsafeFunction "lower"

927−

928−-- | >>> printSQL $ upper "eeee"

929−-- upper(E'eeee')

930−upper

931− :: Expression db from grouping params (nullity 'PGtext)

932− -- ^ string to upper case

933− -> Expression db from grouping params (nullity 'PGtext)

934−upper = unsafeFunction "upper"

935−

936−-- | >>> printSQL $ charLength "four"

937−-- char_length(E'four')

938−charLength

939− :: Expression db from grouping params (nullity 'PGtext)

940− -- ^ string to measure

941− -> Expression db from grouping params (nullity 'PGint4)

942−charLength = unsafeFunction "char_length"

943−

944−-- | The `like` expression returns true if the @string@ matches

945−-- the supplied @pattern@. If @pattern@ does not contain percent signs

946−-- or underscores, then the pattern only represents the string itself;

947−-- in that case `like` acts like the equals operator. An underscore (_)

948−-- in pattern stands for (matches) any single character; a percent sign (%)

949−-- matches any sequence of zero or more characters.

950−--

951−-- >>> printSQL $ "abc" `like` "a%"

952−-- (E'abc' LIKE E'a%')

953−like

954− :: Expression db from grouping params (nullity 'PGtext)

955− -- ^ string

956− -> Expression db from grouping params (nullity 'PGtext)

957− -- ^ pattern

958− -> Expression db from grouping params (nullity 'PGbool)

959−like = unsafeBinaryOp "LIKE"

960−

961−{-----------------------------------------

962− -- json and jsonb support

963−

964−See https://www.postgresql.org/docs/10/static/functions-json.html -- most

965−comments lifted directly from this page.

966−

967−Table 9.44: json and jsonb operators

968−-----------------------------------------}

969−

970−-- | Get JSON value (object field or array element) at a key.

971−(.->)

972− :: (json `In` PGJsonType, key `In` PGJsonKey)

973− => Expression db from grouping params (nullity json)

974− -> Expression db from grouping params (nullity key)

975− -> Expression db from grouping params ('Null json)

976−infixl 8 .->

977−(.->) = unsafeBinaryOp "->"

978−

979−-- | Get JSON value (object field or array element) at a key, as text.

980−(.->>)

981− :: (json `In` PGJsonType, key `In` PGJsonKey)

982− => Expression db from grouping params (nullity json)

983− -> Expression db from grouping params (nullity key)

984− -> Expression db from grouping params ('Null 'PGtext)

985−infixl 8 .->>

986−(.->>) = unsafeBinaryOp "->>"

987−

988−-- | Get JSON value at a specified path.

989−(.#>)

990− :: (json `In` PGJsonType, PGTextArray "(.#>)" path)

991− => Expression db from grouping params (nullity json)

992− -> Expression db from grouping params (nullity path)

993− -> Expression db from grouping params ('Null json)

994−infixl 8 .#>

995−(.#>) = unsafeBinaryOp "#>"

996−

997−-- | Get JSON value at a specified path as text.

998−(.#>>)

999− :: (json `In` PGJsonType, PGTextArray "(.#>>)" path)

1000− => Expression db from grouping params (nullity json)

1001− -> Expression db from grouping params (nullity path)

1002− -> Expression db from grouping params ('Null 'PGtext)

1003−infixl 8 .#>>

1004−(.#>>) = unsafeBinaryOp "#>>"

1005−

1006−-- Additional jsonb operators

1007−

1008−-- | Does the left JSON value contain the right JSON path/value entries at the

1009−-- top level?

1010−(.@>)

1011− :: Expression db from grouping params (nullity 'PGjsonb)

1012− -> Expression db from grouping params (nullity 'PGjsonb)

1013− -> Condition db from grouping params

1014−infixl 9 .@>

1015−(.@>) = unsafeBinaryOp "@>"

1016−

1017−-- | Are the left JSON path/value entries contained at the top level within the

1018−-- right JSON value?

1019−(.<@)

1020− :: Expression db from grouping params (nullity 'PGjsonb)

1021− -> Expression db from grouping params (nullity 'PGjsonb)

1022− -> Condition db from grouping params

1023−infixl 9 .<@

1024−(.<@) = unsafeBinaryOp "<@"

1025−

1026−-- | Does the string exist as a top-level key within the JSON value?

1027−(.?)

1028− :: Expression db from grouping params (nullity 'PGjsonb)

1029− -> Expression db from grouping params (nullity 'PGtext)

1030− -> Condition db from grouping params

1031−infixl 9 .?

1032−(.?) = unsafeBinaryOp "?"

1033−

1034−-- | Do any of these array strings exist as top-level keys?

1035−(.?|)

1036− :: Expression db from grouping params (nullity 'PGjsonb)

1037− -> Expression db from grouping params (nullity ('PGvararray ('NotNull 'PGtext)))

1038− -> Condition db from grouping params

1039−infixl 9 .?|

1040−(.?|) = unsafeBinaryOp "?|"

1041−

1042−-- | Do all of these array strings exist as top-level keys?

1043−(.?&)

1044− :: Expression db from grouping params (nullity 'PGjsonb)

1045− -> Expression db from grouping params (nullity ('PGvararray ('NotNull 'PGtext)))

1046− -> Condition db from grouping params

1047−infixl 9 .?&

1048−(.?&) = unsafeBinaryOp "?&"

1049−

1050−-- | Concatenate two jsonb values into a new jsonb value.

1051−instance

1052− Semigroup (Expression db from grouping param (nullity 'PGjsonb)) where

1053− (<>) = unsafeBinaryOp "||"

1054−

1055−-- | Delete a key or keys from a JSON object, or remove an array element.

1056−--

1057−-- If the right operand is..

1058−--

1059−-- @ text @: Delete key/value pair or string element from left operand. Key/value pairs

1060−-- are matched based on their key value.

1061−--

1062−-- @ text[] @: Delete multiple key/value pairs or string elements

1063−-- from left operand. Key/value pairs are matched based on their key value.

1064−--

1065−-- @ integer @: Delete the array element with specified index (Negative integers

1066−-- count from the end). Throws an error if top level container is not an array.

1067−(.-.)

1068− :: (key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]) -- hlint error without parens here

1069− => Expression db from grouping params (nullity 'PGjsonb)

1070− -> Expression db from grouping params (nullity key)

1071− -> Expression db from grouping params (nullity 'PGjsonb)

1072−infixl 6 .-.

1073−(.-.) = unsafeBinaryOp "-"

1074−

1075−-- | Delete the field or element with specified path (for JSON arrays, negative

1076−-- integers count from the end)

1077−(#-.)

1078− :: PGTextArray "(#-.)" arrayty

1079− => Expression db from grouping params (nullity 'PGjsonb)

1080− -> Expression db from grouping params (nullity arrayty)

1081− -> Expression db from grouping params (nullity 'PGjsonb)

1082−infixl 6 #-.

1083−(#-.) = unsafeBinaryOp "#-"

1084−

1085−{-----------------------------------------

1086−Table 9.45: JSON creation functions

1087−-----------------------------------------}

1088−

1089−-- | Literal binary JSON

1090−jsonbLit

1091− :: JSON.ToJSON x

1092− => x -> Expression (commons :=> schemas) from grouping params (nullity 'PGjsonb)

1093−jsonbLit = cast jsonb . UnsafeExpression

1094− . singleQuotedUtf8 . toStrict . JSON.encode

1095−

1096−-- | Literal JSON

1097−jsonLit

1098− :: JSON.ToJSON x

1099− => x -> Expression (commons :=> schemas) from grouping params (nullity 'PGjson)

1100−jsonLit = cast json . UnsafeExpression

1101− . singleQuotedUtf8 . toStrict . JSON.encode

1102−

1103−-- | Returns the value as json. Arrays and composites are converted

1104−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

1105−-- type to json, the cast function will be used to perform the conversion;

1106−-- otherwise, a scalar value is produced. For any scalar type other than a

1107−-- number, a Boolean, or a null value, the text representation will be used, in

1108−-- such a fashion that it is a valid json value.

1109−toJson

1110− :: Expression db from grouping params (nullity ty)

1111− -> Expression db from grouping params (nullity 'PGjson)

1112−toJson = unsafeFunction "to_json"

1113−

1114−-- | Returns the value as jsonb. Arrays and composites are converted

1115−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

1116−-- type to json, the cast function will be used to perform the conversion;

1117−-- otherwise, a scalar value is produced. For any scalar type other than a

1118−-- number, a Boolean, or a null value, the text representation will be used, in

1119−-- such a fashion that it is a valid jsonb value.

1120−toJsonb

1121− :: Expression db from grouping params (nullity ty)

1122− -> Expression db from grouping params (nullity 'PGjsonb)

1123−toJsonb = unsafeFunction "to_jsonb"

1124−

1125−-- | Returns the array as a JSON array. A PostgreSQL multidimensional array

1126−-- becomes a JSON array of arrays.

1127−arrayToJson

1128− :: PGArray "arrayToJson" arr

1129− => Expression db from grouping params (nullity arr)

1130− -> Expression db from grouping params (nullity 'PGjson)

1131−arrayToJson = unsafeFunction "array_to_json"

1132−

1133−-- | Returns the row as a JSON object.

1134−rowToJson

1135− :: Expression db from grouping params (nullity ('PGcomposite ty))

1136− -> Expression db from grouping params (nullity 'PGjson)

1137−rowToJson = unsafeFunction "row_to_json"

1138−

1139−-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic

1140−-- argument list.

1141−jsonBuildArray

1142− :: SListI elems

1143− => NP (Expression db from grouping params) elems

1144− -> Expression db from grouping params (nullity 'PGjson)

1145−jsonBuildArray = unsafeVariadicFunction "json_build_array"

1146−

1147−-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a

1148−-- variadic argument list.

1149−jsonbBuildArray

1150− :: SListI elems

1151− => NP (Expression db from grouping params) elems

1152− -> Expression db from grouping params (nullity 'PGjsonb)

1153−jsonbBuildArray = unsafeVariadicFunction "jsonb_build_array"

1154−

1155−unsafeRowFunction

1156− :: All Top elems

1157− => NP (Aliased (Expression db from grouping params)) elems

1158− -> [ByteString]

1159−unsafeRowFunction =

1160− (`appEndo` []) . hcfoldMap (Proxy :: Proxy Top)

1161− (\(col `As` name) -> Endo $ \xs ->

1162− renderAliasString name : renderExpression col : xs)

1163−

1164−-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic

1165−-- argument list. The elements of the argument list must alternate between text

1166−-- and values.

1167−jsonBuildObject

1168− :: All Top elems

1169− => NP (Aliased (Expression db from grouping params)) elems

1170− -> Expression db from grouping params (nullity 'PGjson)

1171−jsonBuildObject

1172− = unsafeFunction "json_build_object"

1173− . UnsafeExpression

1174− . commaSeparated

1175− . unsafeRowFunction

1176−

1177−-- | Builds a possibly-heterogeneously-typed (binary) JSON object out of a

1178−-- variadic argument list. The elements of the argument list must alternate

1179−-- between text and values.

1180−jsonbBuildObject

1181− :: All Top elems

1182− => NP (Aliased (Expression db from grouping params)) elems

1183− -> Expression db from grouping params (nullity 'PGjsonb)

1184−jsonbBuildObject

1185− = unsafeFunction "jsonb_build_object"

1186− . UnsafeExpression

1187− . commaSeparated

1188− . unsafeRowFunction

1189−

1190−-- | Builds a JSON object out of a text array. The array must have either

1191−-- exactly one dimension with an even number of members, in which case they are

1192−-- taken as alternating key/value pairs, or two dimensions such that each inner

1193−-- array has exactly two elements, which are taken as a key/value pair.

1194−jsonObject

1195− :: PGArrayOf "jsonObject" arr ('NotNull 'PGtext)

1196− => Expression db from grouping params (nullity arr)

1197− -> Expression db from grouping params (nullity 'PGjson)

1198−jsonObject = unsafeFunction "json_object"

1199−

1200−-- | Builds a binary JSON object out of a text array. The array must have either

1201−-- exactly one dimension with an even number of members, in which case they are

1202−-- taken as alternating key/value pairs, or two dimensions such that each inner

1203−-- array has exactly two elements, which are taken as a key/value pair.

1204−jsonbObject

1205− :: PGArrayOf "jsonbObject" arr ('NotNull 'PGtext)

1206− => Expression db from grouping params (nullity arr)

1207− -> Expression db from grouping params (nullity 'PGjsonb)

1208−jsonbObject = unsafeFunction "jsonb_object"

1209−

1210−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

1211−-- keys and one for values, that are zipped pairwise to create a JSON object.

1212−jsonZipObject

1213− :: ( PGArrayOf "jsonZipObject" keysArray ('NotNull 'PGtext)

1214− , PGArrayOf "jsonZipObject" valuesArray ('NotNull 'PGtext))

1215− => Expression db from grouping params (nullity keysArray)

1216− -> Expression db from grouping params (nullity valuesArray)

1217− -> Expression db from grouping params (nullity 'PGjson)

1218−jsonZipObject ks vs =

1219− unsafeVariadicFunction "json_object" (ks :* vs :* Nil)

1220−

1221−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

1222−-- keys and one for values, that are zipped pairwise to create a binary JSON

1223−-- object.

1224−jsonbZipObject

1225− :: ( PGArrayOf "jsonbZipObject" keysArray ('NotNull 'PGtext)

1226− , PGArrayOf "jsonbZipObject" valuesArray ('NotNull 'PGtext))

1227− => Expression db from grouping params (nullity keysArray)

1228− -> Expression db from grouping params (nullity valuesArray)

1229− -> Expression db from grouping params (nullity 'PGjsonb)

1230−jsonbZipObject ks vs =

1231− unsafeVariadicFunction "jsonb_object" (ks :* vs :* Nil)

1232−

1233−{-----------------------------------------

1234−Table 9.46: JSON processing functions

1235−-----------------------------------------}

1236−

1237−-- | Returns the number of elements in the outermost JSON array.

1238−jsonArrayLength

1239− :: Expression db from grouping params (nullity 'PGjson)

1240− -> Expression db from grouping params (nullity 'PGint4)

1241−jsonArrayLength = unsafeFunction "json_array_length"

1242−

1243−-- | Returns the number of elements in the outermost binary JSON array.

1244−jsonbArrayLength

1245− :: Expression db from grouping params (nullity 'PGjsonb)

1246− -> Expression db from grouping params (nullity 'PGint4)

1247−jsonbArrayLength = unsafeFunction "jsonb_array_length"

1248−

1249−-- | Returns JSON value pointed to by the given path (equivalent to #>

1250−-- operator).

1251−jsonExtractPath

1252− :: SListI elems

1253− => Expression db from grouping params (nullity 'PGjson)

1254− -> NP (Expression db from grouping params) elems

1255− -> Expression db from grouping params (nullity 'PGjsonb)

1256−jsonExtractPath x xs =

1257− unsafeVariadicFunction "json_extract_path" (x :* xs)

1258−

1259−-- | Returns JSON value pointed to by the given path (equivalent to #>

1260−-- operator).

1261−jsonbExtractPath

1262− :: SListI elems

1263− => Expression db from grouping params (nullity 'PGjsonb)

1264− -> NP (Expression db from grouping params) elems

1265− -> Expression db from grouping params (nullity 'PGjsonb)

1266−jsonbExtractPath x xs =

1267− unsafeVariadicFunction "jsonb_extract_path" (x :* xs)

1268−

1269−-- | Returns JSON value pointed to by the given path (equivalent to #>

1270−-- operator), as text.

1271−jsonExtractPathAsText

1272− :: SListI elems

1273− => Expression db from grouping params (nullity 'PGjson)

1274− -> NP (Expression db from grouping params) elems

1275− -> Expression db from grouping params (nullity 'PGjson)

1276−jsonExtractPathAsText x xs =

1277− unsafeVariadicFunction "json_extract_path_text" (x :* xs)

1278−

1279−-- | Returns JSON value pointed to by the given path (equivalent to #>

1280−-- operator), as text.

1281−jsonbExtractPathAsText

1282− :: SListI elems

1283− => Expression db from grouping params (nullity 'PGjsonb)

1284− -> NP (Expression db from grouping params) elems

1285− -> Expression db from grouping params (nullity 'PGjsonb)

1286−jsonbExtractPathAsText x xs =

1287− unsafeVariadicFunction "jsonb_extract_path_text" (x :* xs)

1288−

1289−-- | Returns the type of the outermost JSON value as a text string. Possible

1290−-- types are object, array, string, number, boolean, and null.

1291−jsonTypeof

1292− :: Expression db from grouping params (nullity 'PGjson)

1293− -> Expression db from grouping params (nullity 'PGtext)

1294−jsonTypeof = unsafeFunction "json_typeof"

1295−

1296−-- | Returns the type of the outermost binary JSON value as a text string.

1297−-- Possible types are object, array, string, number, boolean, and null.

1298−jsonbTypeof

1299− :: Expression db from grouping params (nullity 'PGjsonb)

1300− -> Expression db from grouping params (nullity 'PGtext)

1301−jsonbTypeof = unsafeFunction "jsonb_typeof"

1302−

1303−-- | Returns its argument with all object fields that have null values omitted.

1304−-- Other null values are untouched.

1305−jsonStripNulls

1306− :: Expression db from grouping params (nullity 'PGjson)

1307− -> Expression db from grouping params (nullity 'PGjson)

1308−jsonStripNulls = unsafeFunction "json_strip_nulls"

1309−

1310−-- | Returns its argument with all object fields that have null values omitted.

1311−-- Other null values are untouched.

1312−jsonbStripNulls

1313− :: Expression db from grouping params (nullity 'PGjsonb)

1314− -> Expression db from grouping params (nullity 'PGjsonb)

1315−jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"

1316−

1317−-- | @ jsonbSet target path new_value create_missing @

1318−--

1319−-- Returns target with the section designated by path replaced by new_value,

1320−-- or with new_value added if create_missing is true ( default is true) and the

1321−-- item designated by path does not exist. As with the path orientated

1322−-- operators, negative integers that appear in path count from the end of JSON

1323−-- arrays.

1324−jsonbSet

1325− :: PGTextArray "jsonbSet" arr

1326− => Expression db from grouping params (nullity 'PGjsonb)

1327− -> Expression db from grouping params (nullity arr)

1328− -> Expression db from grouping params (nullity 'PGjsonb)

1329− -> Maybe (Expression db from grouping params (nullity 'PGbool))

1330− -> Expression db from grouping params (nullity 'PGjsonb)

1331−jsonbSet tgt path val createMissing = case createMissing of

1332− Just m -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* m :* Nil)

1333− Nothing -> unsafeVariadicFunction "jsonb_set" (tgt :* path :* val :* Nil)

1334−

1335−-- | @ jsonbInsert target path new_value insert_after @

1336−--

1337−-- Returns target with new_value inserted. If target section designated by

1338−-- path is in a JSONB array, new_value will be inserted before target or after

1339−-- if insert_after is true (default is false). If target section designated by

1340−-- path is in JSONB object, new_value will be inserted only if target does not

1341−-- exist. As with the path orientated operators, negative integers that appear

1342−-- in path count from the end of JSON arrays.

1343−jsonbInsert

1344− :: PGTextArray "jsonbInsert" arr

1345− => Expression db from grouping params (nullity 'PGjsonb)

1346− -> Expression db from grouping params (nullity arr)

1347− -> Expression db from grouping params (nullity 'PGjsonb)

1348− -> Maybe (Expression db from grouping params (nullity 'PGbool))

1349− -> Expression db from grouping params (nullity 'PGjsonb)

1350−jsonbInsert tgt path val insertAfter = case insertAfter of

1351− Just i -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* i :* Nil)

1352− Nothing -> unsafeVariadicFunction "jsonb_insert" (tgt :* path :* val :* Nil)

1353−

1354−-- | Returns its argument as indented JSON text.

1355−jsonbPretty

1356− :: Expression db from grouping params (nullity 'PGjsonb)

1357− -> Expression db from grouping params (nullity 'PGtext)

1358−jsonbPretty = unsafeFunction "jsonb_pretty"

1359−

1360−{-----------------------------------------

1361−aggregation

1362−-----------------------------------------}

1363−

1364−-- | escape hatch to define aggregate functions

1365−unsafeAggregate

1366− :: ByteString -- ^ aggregate function

1367− -> Expression db from 'Ungrouped params (xty)

1368− -> Expression db from ('Grouped bys) params (yty)

1369−unsafeAggregate fun x = UnsafeExpression $ mconcat

1370− [fun, "(", renderExpression x, ")"]

1371−

1372−-- | escape hatch to define aggregate functions over distinct values

1373−unsafeAggregateDistinct

1374− :: ByteString -- ^ aggregate function

1375− -> Expression db from 'Ungrouped params (xty)

1376− -> Expression db from ('Grouped bys) params (yty)

1377−unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat

1378− [fun, "(DISTINCT ", renderExpression x, ")"]

1379−

1380−-- | >>> :{

1381−-- let

1382−-- expression :: Expression db '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Grouped bys) params ('Null 'PGnumeric)

1383−-- expression = sum_ #col

1384−-- in printSQL expression

1385−-- :}

1386−-- sum("col")

1387−sum_

1388− :: ty `In` PGNum

1389− => Expression db from 'Ungrouped params (nullity ty)

1390− -- ^ what to sum

1391− -> Expression db from ('Grouped bys) params (nullity ty)

1392−sum_ = unsafeAggregate "sum"

1393−

1394−-- | >>> :{

1395−-- let

1396−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGnumeric]] ('Grouped bys) params (nullity 'PGnumeric)

1397−-- expression = sumDistinct #col

1398−-- in printSQL expression

1399−-- :}

1400−-- sum(DISTINCT "col")

1401−sumDistinct

1402− :: ty `In` PGNum

1403− => Expression db from 'Ungrouped params (nullity ty)

1404− -- ^ what to sum

1405− -> Expression db from ('Grouped bys) params (nullity ty)

1406−sumDistinct = unsafeAggregateDistinct "sum"

1407−

1408−-- | A constraint for `PGType`s that you can take averages of and the resulting

1409−-- `PGType`.

1410−class PGAvg ty avg | ty -> avg where

1411− avg, avgDistinct

1412− :: Expression db from 'Ungrouped params (nullity ty)

1413− -- ^ what to average

1414− -> Expression db from ('Grouped bys) params (nullity avg)

1415− avg = unsafeAggregate "avg"

1416− avgDistinct = unsafeAggregateDistinct "avg"

1417−instance PGAvg 'PGint2 'PGnumeric

1418−instance PGAvg 'PGint4 'PGnumeric

1419−instance PGAvg 'PGint8 'PGnumeric

1420−instance PGAvg 'PGnumeric 'PGnumeric

1421−instance PGAvg 'PGfloat4 'PGfloat8

1422−instance PGAvg 'PGfloat8 'PGfloat8

1423−instance PGAvg 'PGinterval 'PGinterval

1424−

1425−-- | >>> :{

1426−-- let

1427−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1428−-- expression = bitAnd #col

1429−-- in printSQL expression

1430−-- :}

1431−-- bit_and("col")

1432−bitAnd

1433− :: int `In` PGIntegral

1434− => Expression db from 'Ungrouped params (nullity int)

1435− -- ^ what to aggregate

1436− -> Expression db from ('Grouped bys) params (nullity int)

1437−bitAnd = unsafeAggregate "bit_and"

1438−

1439−-- | >>> :{

1440−-- let

1441−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1442−-- expression = bitOr #col

1443−-- in printSQL expression

1444−-- :}

1445−-- bit_or("col")

1446−bitOr

1447− :: int `In` PGIntegral

1448− => Expression db from 'Ungrouped params (nullity int)

1449− -- ^ what to aggregate

1450− -> Expression db from ('Grouped bys) params (nullity int)

1451−bitOr = unsafeAggregate "bit_or"

1452−

1453−-- | >>> :{

1454−-- let

1455−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1456−-- expression = bitAndDistinct #col

1457−-- in printSQL expression

1458−-- :}

1459−-- bit_and(DISTINCT "col")

1460−bitAndDistinct

1461− :: int `In` PGIntegral

1462− => Expression db from 'Ungrouped params (nullity int)

1463− -- ^ what to aggregate

1464− -> Expression db from ('Grouped bys) params (nullity int)

1465−bitAndDistinct = unsafeAggregateDistinct "bit_and"

1466−

1467−-- | >>> :{

1468−-- let

1469−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

1470−-- expression = bitOrDistinct #col

1471−-- in printSQL expression

1472−-- :}

1473−-- bit_or(DISTINCT "col")

1474−bitOrDistinct

1475− :: int `In` PGIntegral

1476− => Expression db from 'Ungrouped params (nullity int)

1477− -- ^ what to aggregate

1478− -> Expression db from ('Grouped bys) params (nullity int)

1479−bitOrDistinct = unsafeAggregateDistinct "bit_or"

1480−

1481−-- | >>> :{

1482−-- let

1483−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1484−-- expression = boolAnd #col

1485−-- in printSQL expression

1486−-- :}

1487−-- bool_and("col")

1488−boolAnd

1489− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1490− -- ^ what to aggregate

1491− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1492−boolAnd = unsafeAggregate "bool_and"

1493−

1494−-- | >>> :{

1495−-- let

1496−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1497−-- expression = boolOr #col

1498−-- in printSQL expression

1499−-- :}

1500−-- bool_or("col")

1501−boolOr

1502− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1503− -- ^ what to aggregate

1504− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1505−boolOr = unsafeAggregate "bool_or"

1506−

1507−-- | >>> :{

1508−-- let

1509−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1510−-- expression = boolAndDistinct #col

1511−-- in printSQL expression

1512−-- :}

1513−-- bool_and(DISTINCT "col")

1514−boolAndDistinct

1515− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1516− -- ^ what to aggregate

1517− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1518−boolAndDistinct = unsafeAggregateDistinct "bool_and"

1519−

1520−-- | >>> :{

1521−-- let

1522−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1523−-- expression = boolOrDistinct #col

1524−-- in printSQL expression

1525−-- :}

1526−-- bool_or(DISTINCT "col")

1527−boolOrDistinct

1528− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1529− -- ^ what to aggregate

1530− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1531−boolOrDistinct = unsafeAggregateDistinct "bool_or"

1532−

1533−-- | A special aggregation that does not require an input

1534−--

1535−-- >>> printSQL countStar

1536−-- count(*)

1537−countStar

1538− :: Expression db from ('Grouped bys) params ('NotNull 'PGint8)

1539−countStar = UnsafeExpression $ "count(*)"

1540−

1541−-- | >>> :{

1542−-- let

1543−-- expression :: Expression db '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

1544−-- expression = count #col

1545−-- in printSQL expression

1546−-- :}

1547−-- count("col")

1548−count

1549− :: Expression db from 'Ungrouped params ty

1550− -- ^ what to count

1551− -> Expression db from ('Grouped bys) params ('NotNull 'PGint8)

1552−count = unsafeAggregate "count"

1553−

1554−-- | >>> :{

1555−-- let

1556−-- expression :: Expression db '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

1557−-- expression = countDistinct #col

1558−-- in printSQL expression

1559−-- :}

1560−-- count(DISTINCT "col")

1561−countDistinct

1562− :: Expression db from 'Ungrouped params ty

1563− -- ^ what to count

1564− -> Expression db from ('Grouped bys) params ('NotNull 'PGint8)

1565−countDistinct = unsafeAggregateDistinct "count"

1566−

1567−-- | synonym for `boolAnd`

1568−--

1569−-- >>> :{

1570−-- let

1571−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1572−-- expression = every #col

1573−-- in printSQL expression

1574−-- :}

1575−-- every("col")

1576−every

1577− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1578− -- ^ what to aggregate

1579− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1580−every = unsafeAggregate "every"

1581−

1582−-- | synonym for `boolAndDistinct`

1583−--

1584−-- >>> :{

1585−-- let

1586−-- expression :: Expression db '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1587−-- expression = everyDistinct #col

1588−-- in printSQL expression

1589−-- :}

1590−-- every(DISTINCT "col")

1591−everyDistinct

1592− :: Expression db from 'Ungrouped params (nullity 'PGbool)

1593− -- ^ what to aggregate

1594− -> Expression db from ('Grouped bys) params (nullity 'PGbool)

1595−everyDistinct = unsafeAggregateDistinct "every"

1596−

1597−-- | minimum and maximum aggregation

1598−max_, min_, maxDistinct, minDistinct

1599− :: Expression db from 'Ungrouped params (nullity ty)

1600− -- ^ what to aggregate

1601− -> Expression db from ('Grouped bys) params (nullity ty)

1602−max_ = unsafeAggregate "max"

1603−min_ = unsafeAggregate "min"

1604−maxDistinct = unsafeAggregateDistinct "max"

1605−minDistinct = unsafeAggregateDistinct "min"

1606−

1607−{-----------------------------------------

1608−type expressions

1609−-----------------------------------------}

1610−

1611−-- | `TypeExpression`s are used in `cast`s and `createTable` commands.

1612−newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)

1613− = UnsafeTypeExpression { renderTypeExpression :: ByteString }

1614− deriving (GHC.Generic,Show,Eq,Ord,NFData)

1615−

1616−-- | The enum or composite type in a `Typedef` can be expressed by its alias.

1617−typedef

1618− :: (Has sch schemas schema, Has td schema ('Typedef ty))

1619− => QualifiedAlias sch td

1620− -> TypeExpression schemas (nullity ty)

1621−typedef = UnsafeTypeExpression . renderQualifiedAlias

1622−

1623−-- | The composite type corresponding to a `Table` definition can be expressed

1624−-- by its alias.

1625−typetable

1626− :: (Has sch schemas schema, Has tab schema ('Table table))

1627− => QualifiedAlias sch tab

1628− -> TypeExpression schemas (nullity ('PGcomposite (TableToRow table)))

1629−typetable = UnsafeTypeExpression . renderQualifiedAlias

1630−

1631−-- | The composite type corresponding to a `View` definition can be expressed

1632−-- by its alias.

1633−typeview

1634− :: (Has sch schemas schema, Has vw schema ('View view))

1635− => QualifiedAlias sch vw

1636− -> TypeExpression schemas (nullity ('PGcomposite view))

1637−typeview = UnsafeTypeExpression . renderQualifiedAlias

1638−

1639−-- | logical Boolean (true/false)

1640−bool :: TypeExpression db (nullity 'PGbool)

1641−bool = UnsafeTypeExpression "bool"

1642−-- | signed two-byte integer

1643−int2, smallint :: TypeExpression db (nullity 'PGint2)

1644−int2 = UnsafeTypeExpression "int2"

1645−smallint = UnsafeTypeExpression "smallint"

1646−-- | signed four-byte integer

1647−int4, int, integer :: TypeExpression db (nullity 'PGint4)

1648−int4 = UnsafeTypeExpression "int4"

1649−int = UnsafeTypeExpression "int"

1650−integer = UnsafeTypeExpression "integer"

1651−-- | signed eight-byte integer

1652−int8, bigint :: TypeExpression db (nullity 'PGint8)

1653−int8 = UnsafeTypeExpression "int8"

1654−bigint = UnsafeTypeExpression "bigint"

1655−-- | arbitrary precision numeric type

1656−numeric :: TypeExpression db (nullity 'PGnumeric)

1657−numeric = UnsafeTypeExpression "numeric"

1658−-- | single precision floating-point number (4 bytes)

1659−float4, real :: TypeExpression db (nullity 'PGfloat4)

1660−float4 = UnsafeTypeExpression "float4"

1661−real = UnsafeTypeExpression "real"

1662−-- | double precision floating-point number (8 bytes)

1663−float8, doublePrecision :: TypeExpression db (nullity 'PGfloat8)

1664−float8 = UnsafeTypeExpression "float8"

1665−doublePrecision = UnsafeTypeExpression "double precision"

1666−-- | variable-length character string

1667−text :: TypeExpression db (nullity 'PGtext)

1668−text = UnsafeTypeExpression "text"

1669−-- | fixed-length character string

1670−char, character

1671− :: forall n db nullity. (KnownNat n, 1 <= n)

1672− => TypeExpression db (nullity ('PGchar n))

1673−char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"

1674−character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"

1675−-- | variable-length character string

1676−varchar, characterVarying

1677− :: forall n db nullity. (KnownNat n, 1 <= n)

1678− => TypeExpression db (nullity ('PGvarchar n))

1679−varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"

1680−characterVarying = UnsafeTypeExpression $

1681− "character varying(" <> renderNat @n <> ")"

1682−-- | binary data ("byte array")

1683−bytea :: TypeExpression db (nullity 'PGbytea)

1684−bytea = UnsafeTypeExpression "bytea"

1685−-- | date and time (no time zone)

1686−timestamp :: TypeExpression db (nullity 'PGtimestamp)

1687−timestamp = UnsafeTypeExpression "timestamp"

1688−-- | date and time, including time zone

1689−timestampWithTimeZone :: TypeExpression db (nullity 'PGtimestamptz)

1690−timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

1691−-- | calendar date (year, month, day)

1692−date :: TypeExpression db (nullity 'PGdate)

1693−date = UnsafeTypeExpression "date"

1694−-- | time of day (no time zone)

1695−time :: TypeExpression db (nullity 'PGtime)

1696−time = UnsafeTypeExpression "time"

1697−-- | time of day, including time zone

1698−timeWithTimeZone :: TypeExpression db (nullity 'PGtimetz)

1699−timeWithTimeZone = UnsafeTypeExpression "time with time zone"

1700−-- | time span

1701−interval :: TypeExpression db (nullity 'PGinterval)

1702−interval = UnsafeTypeExpression "interval"

1703−-- | universally unique identifier

1704−uuid :: TypeExpression db (nullity 'PGuuid)

1705−uuid = UnsafeTypeExpression "uuid"

1706−-- | IPv4 or IPv6 host address

1707−inet :: TypeExpression db (nullity 'PGinet)

1708−inet = UnsafeTypeExpression "inet"

1709−-- | textual JSON data

1710−json :: TypeExpression db (nullity 'PGjson)

1711−json = UnsafeTypeExpression "json"

1712−-- | binary JSON data, decomposed

1713−jsonb :: TypeExpression db (nullity 'PGjsonb)

1714−jsonb = UnsafeTypeExpression "jsonb"

1715−-- | variable length array

1716−vararray

1717− :: TypeExpression db pg

1718− -> TypeExpression db (nullity ('PGvararray pg))

1719−vararray ty = UnsafeTypeExpression $ renderTypeExpression ty <> "[]"

1720−-- | fixed length array

1721−--

1722−-- >>> renderTypeExpression (fixarray @2 json)

1723−-- "json[2]"

1724−fixarray

1725− :: forall n db nullity pg. KnownNat n

1726− => TypeExpression db pg

1727− -> TypeExpression db (nullity ('PGfixarray n pg))

1728−fixarray ty = UnsafeTypeExpression $

1729− renderTypeExpression ty <> "[" <> renderNat @n <> "]"

1730−

1731−-- | `pgtype` is a demoted version of a `PGType`

1732−class PGTyped db (ty :: NullityType) where

1733− pgtype :: TypeExpression db ty

1734−instance PGTyped db (nullity 'PGbool) where pgtype = bool

1735−instance PGTyped db (nullity 'PGint2) where pgtype = int2

1736−instance PGTyped db (nullity 'PGint4) where pgtype = int4

1737−instance PGTyped db (nullity 'PGint8) where pgtype = int8

1738−instance PGTyped db (nullity 'PGnumeric) where pgtype = numeric

1739−instance PGTyped db (nullity 'PGfloat4) where pgtype = float4

1740−instance PGTyped db (nullity 'PGfloat8) where pgtype = float8

1741−instance PGTyped db (nullity 'PGtext) where pgtype = text

1742−instance (KnownNat n, 1 <= n)

1743− => PGTyped db (nullity ('PGchar n)) where pgtype = char @n

1744−instance (KnownNat n, 1 <= n)

1745− => PGTyped db (nullity ('PGvarchar n)) where pgtype = varchar @n

1746−instance PGTyped db (nullity 'PGbytea) where pgtype = bytea

1747−instance PGTyped db (nullity 'PGtimestamp) where pgtype = timestamp

1748−instance PGTyped db (nullity 'PGtimestamptz) where pgtype = timestampWithTimeZone

1749−instance PGTyped db (nullity 'PGdate) where pgtype = date

1750−instance PGTyped db (nullity 'PGtime) where pgtype = time

1751−instance PGTyped db (nullity 'PGtimetz) where pgtype = timeWithTimeZone

1752−instance PGTyped db (nullity 'PGinterval) where pgtype = interval

1753−instance PGTyped db (nullity 'PGuuid) where pgtype = uuid

1754−instance PGTyped db (nullity 'PGjson) where pgtype = json

1755−instance PGTyped db (nullity 'PGjsonb) where pgtype = jsonb

1756−instance PGTyped db ty

1757− => PGTyped db (nullity ('PGvararray ty)) where

1758− pgtype = vararray (pgtype @db @ty)

1759−instance (KnownNat n, PGTyped db ty)

1760− => PGTyped db (nullity ('PGfixarray n ty)) where

1761− pgtype = fixarray @n (pgtype @db @ty)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hsnew file+462

@@ -0,0 +1,462 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Aggregate

3+Description: Aggregate functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Aggregate functions

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , DeriveGeneric

14+ , FlexibleContexts

15+ , FlexibleInstances

16+ , FunctionalDependencies

17+ , LambdaCase

18+ , MultiParamTypeClasses

19+ , OverloadedStrings

20+ , PolyKinds

21+ , TypeFamilies

22+ , TypeOperators

23+ , UndecidableInstances

24+#-}

25+

26+module Squeal.PostgreSQL.Expression.Aggregate

27+ ( Aggregate (..)

28+ , Distinction (..)

29+ , PGSum

30+ , PGAvg

31+ ) where

32+

33+import Control.DeepSeq

34+import Data.ByteString (ByteString)

35+import Data.Kind

36+import GHC.TypeLits

37+

38+import qualified GHC.Generics as GHC

39+import qualified Generics.SOP as SOP

40+

41+import Squeal.PostgreSQL.Alias

42+import Squeal.PostgreSQL.Expression

43+import Squeal.PostgreSQL.List

44+import Squeal.PostgreSQL.Render

45+import Squeal.PostgreSQL.Schema

46+

47+-- $setup

48+-- >>> import Squeal.PostgreSQL

49+

50+{- |

51+`Aggregate` functions compute a single result from a set of input values.

52+`Aggregate` functions can be used as `GroupedBy` `Expression`s as well

53+as `Squeal.PostgreSQL.Expression.Window.WindowFunction`s.

54+-}

55+class Aggregate expr1 exprN aggr

56+ | aggr -> expr1, aggr -> exprN where

57+

58+ -- | A special aggregation that does not require an input

59+ --

60+ -- >>> :{

61+ -- let

62+ -- expression :: Expression '[] commons ('Grouped bys) schemas params from ('NotNull 'PGint8)

63+ -- expression = countStar

64+ -- in printSQL expression

65+ -- :}

66+ -- count(*)

67+ countStar :: aggr ('NotNull 'PGint8)

68+

69+ -- | >>> :{

70+ -- let

71+ -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null ty]] ('NotNull 'PGint8)

72+ -- expression = count (All #col)

73+ -- in printSQL expression

74+ -- :}

75+ -- count(ALL "col")

76+ count

77+ :: expr1 ty

78+ -- ^ what to count

79+ -> aggr ('NotNull 'PGint8)

80+

81+ -- | >>> :{

82+ -- let

83+ -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Null 'PGnumeric)

84+ -- expression = sum_ (Distinct #col)

85+ -- in printSQL expression

86+ -- :}

87+ -- sum(DISTINCT "col")

88+ sum_

89+ :: expr1 (null ty)

90+ -> aggr ('Null (PGSum ty))

91+

92+ -- | input values, including nulls, concatenated into an array

93+ arrayAgg

94+ :: expr1 ty

95+ -> aggr ('Null ('PGvararray ty))

96+

97+ -- | aggregates values as a JSON array

98+ jsonAgg

99+ :: expr1 ty

100+ -> aggr ('Null 'PGjson)

101+

102+ -- | aggregates values as a JSON array

103+ jsonbAgg

104+ :: expr1 ty

105+ -> aggr ('Null 'PGjsonb)

106+

107+ {- |

108+ the bitwise AND of all non-null input values, or null if none

109+

110+ >>> :{

111+ let

112+ expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)

113+ expression = bitAnd (Distinct #col)

114+ in printSQL expression

115+ :}

116+ bit_and(DISTINCT "col")

117+ -}

118+ bitAnd

119+ :: int `In` PGIntegral

120+ => expr1 (null int)

121+ -- ^ what to aggregate

122+ -> aggr ('Null int)

123+

124+ {- |

125+ the bitwise OR of all non-null input values, or null if none

126+

127+ >>> :{

128+ let

129+ expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)

130+ expression = bitOr (All #col)

131+ in printSQL expression

132+ :}

133+ bit_or(ALL "col")

134+ -}

135+ bitOr

136+ :: int `In` PGIntegral

137+ => expr1 (null int)

138+ -- ^ what to aggregate

139+ -> aggr ('Null int)

140+

141+ {- |

142+ true if all input values are true, otherwise false

143+

144+ >>> :{

145+ let

146+ winFun :: WindowFunction '[] commons 'Ungrouped schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

147+ winFun = boolAnd #col

148+ in printSQL winFun

149+ :}

150+ bool_and("col")

151+ -}

152+ boolAnd

153+ :: expr1 (null 'PGbool)

154+ -- ^ what to aggregate

155+ -> aggr ('Null 'PGbool)

156+

157+ {- |

158+ true if at least one input value is true, otherwise false

159+

160+ >>> :{

161+ let

162+ expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

163+ expression = boolOr (All #col)

164+ in printSQL expression

165+ :}

166+ bool_or(ALL "col")

167+ -}

168+ boolOr

169+ :: expr1 (null 'PGbool)

170+ -- ^ what to aggregate

171+ -> aggr ('Null 'PGbool)

172+

173+ {- |

174+ equivalent to `boolAnd`

175+

176+ >>> :{

177+ let

178+ expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

179+ expression = every (Distinct #col)

180+ in printSQL expression

181+ :}

182+ every(DISTINCT "col")

183+ -}

184+ every

185+ :: expr1 (null 'PGbool)

186+ -- ^ what to aggregate

187+ -> aggr ('Null 'PGbool)

188+

189+ {- |maximum value of expression across all input values-}

190+ max_

191+ :: expr1 (null ty)

192+ -- ^ what to maximize

193+ -> aggr ('Null ty)

194+

195+ -- | minimum value of expression across all input values

196+ min_

197+ :: expr1 (null ty)

198+ -- ^ what to minimize

199+ -> aggr ('Null ty)

200+

201+ -- | the average (arithmetic mean) of all input values

202+ avg

203+ :: expr1 (null ty)

204+ -- ^ what to average

205+ -> aggr ('Null (PGAvg ty))

206+

207+ {- | correlation coefficient

208+

209+ >>> :{

210+ let

211+ expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

212+ expression = corr (All (#y *: #x))

213+ in printSQL expression

214+ :}

215+ corr(ALL "y", "x")

216+ -}

217+ corr

218+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

219+ -> aggr ('Null 'PGfloat8)

220+

221+ {- | population covariance

222+

223+ >>> :{

224+ let

225+ expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

226+ expression = covarPop (All (#y *: #x))

227+ in printSQL expression

228+ :}

229+ covar_pop(ALL "y", "x")

230+ -}

231+ covarPop

232+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

233+ -> aggr ('Null 'PGfloat8)

234+

235+ {- | sample covariance

236+

237+ >>> :{

238+ let

239+ winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

240+ winFun = covarSamp (#y *: #x)

241+ in printSQL winFun

242+ :}

243+ covar_samp("y", "x")

244+ -}

245+ covarSamp

246+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

247+ -> aggr ('Null 'PGfloat8)

248+

249+ {- | average of the independent variable (sum(X)/N)

250+

251+ >>> :{

252+ let

253+ expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

254+ expression = regrAvgX (All (#y *: #x))

255+ in printSQL expression

256+ :}

257+ regr_avgx(ALL "y", "x")

258+ -}

259+ regrAvgX

260+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

261+ -> aggr ('Null 'PGfloat8)

262+

263+ {- | average of the dependent variable (sum(Y)/N)

264+

265+ >>> :{

266+ let

267+ winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

268+ winFun = regrAvgY (#y *: #x)

269+ in printSQL winFun

270+ :}

271+ regr_avgy("y", "x")

272+ -}

273+ regrAvgY

274+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

275+ -> aggr ('Null 'PGfloat8)

276+

277+ {- | number of input rows in which both expressions are nonnull

278+

279+ >>> :{

280+ let

281+ winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGint8)

282+ winFun = regrCount (#y *: #x)

283+ in printSQL winFun

284+ :}

285+ regr_count("y", "x")

286+ -}

287+ regrCount

288+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

289+ -> aggr ('Null 'PGint8)

290+

291+ {- | y-intercept of the least-squares-fit linear equation determined by the (X, Y) pairs

292+ >>> :{

293+ let

294+ expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

295+ expression = regrIntercept (All (#y *: #x))

296+ in printSQL expression

297+ :}

298+ regr_intercept(ALL "y", "x")

299+ -}

300+ regrIntercept

301+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

302+ -> aggr ('Null 'PGfloat8)

303+

304+ -- | @regr_r2(Y, X)@, square of the correlation coefficient

305+ regrR2

306+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

307+ -> aggr ('Null 'PGfloat8)

308+

309+ -- | @regr_slope(Y, X)@, slope of the least-squares-fit linear equation

310+ -- determined by the (X, Y) pairs

311+ regrSlope

312+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

313+ -> aggr ('Null 'PGfloat8)

314+

315+ -- | @regr_sxx(Y, X)@, sum(X^2) - sum(X)^2/N

316+ -- (“sum of squares” of the independent variable)

317+ regrSxx

318+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

319+ -> aggr ('Null 'PGfloat8)

320+

321+ -- | @regr_sxy(Y, X)@, sum(X*Y) - sum(X) * sum(Y)/N

322+ -- (“sum of products” of independent times dependent variable)

323+ regrSxy

324+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

325+ -> aggr ('Null 'PGfloat8)

326+

327+ -- | @regr_syy(Y, X)@, sum(Y^2) - sum(Y)^2/N

328+ -- (“sum of squares” of the dependent variable)

329+ regrSyy

330+ :: exprN '[null 'PGfloat8, null 'PGfloat8]

331+ -> aggr ('Null 'PGfloat8)

332+

333+ -- | historical alias for `stddevSamp`

334+ stddev

335+ :: expr1 (null ty)

336+ -> aggr ('Null (PGAvg ty))

337+

338+ -- | population standard deviation of the input values

339+ stddevPop

340+ :: expr1 (null ty)

341+ -> aggr ('Null (PGAvg ty))

342+

343+ -- | sample standard deviation of the input values

344+ stddevSamp

345+ :: expr1 (null ty)

346+ -> aggr ('Null (PGAvg ty))

347+

348+ -- | historical alias for `varSamp`

349+ variance

350+ :: expr1 (null ty)

351+ -> aggr ('Null (PGAvg ty))

352+

353+ -- | population variance of the input values

354+ -- (square of the population standard deviation)

355+ varPop

356+ :: expr1 (null ty)

357+ -> aggr ('Null (PGAvg ty))

358+

359+ -- | sample variance of the input values

360+ -- (square of the sample standard deviation)

361+ varSamp

362+ :: expr1 (null ty)

363+ -> aggr ('Null (PGAvg ty))

364+

365+{- |

366+`Distinction`s are used for the input of `Aggregate` `Expression`s.

367+`All` invokes the aggregate once for each input row.

368+`Distinct` invokes the aggregate once for each distinct value of the expression

369+(or distinct set of values, for multiple expressions) found in the input

370+-}

371+data Distinction (expr :: kind -> Type) (ty :: kind)

372+ = All (expr ty)

373+ | Distinct (expr ty)

374+ deriving (GHC.Generic,Show,Eq,Ord)

375+instance NFData (Distinction (Expression outer commons grp schemas params from) ty)

376+instance RenderSQL (Distinction (Expression outer commons grp schemas params from) ty) where

377+ renderSQL = \case

378+ All x -> "ALL" <+> renderSQL x

379+ Distinct x -> "DISTINCT" <+> renderSQL x

380+instance SOP.SListI tys => RenderSQL

381+ (Distinction (NP (Expression outer commons grp schemas params from)) tys) where

382+ renderSQL = \case

383+ All xs -> "ALL" <+> renderCommaSeparated renderSQL xs

384+ Distinct xs -> "DISTINCT" <+> renderCommaSeparated renderSQL xs

385+

386+instance Aggregate

387+ (Distinction (Expression outer commons 'Ungrouped schemas params from))

388+ (Distinction (NP (Expression outer commons 'Ungrouped schemas params from)))

389+ (Expression outer commons ('Grouped bys) schemas params from) where

390+ countStar = UnsafeExpression "count(*)"

391+ count = unsafeAggregate1 "count"

392+ sum_ = unsafeAggregate1 "sum"

393+ arrayAgg = unsafeAggregate1 "array_agg"

394+ jsonAgg = unsafeAggregate1 "json_agg"

395+ jsonbAgg = unsafeAggregate1 "jsonb_agg"

396+ bitAnd = unsafeAggregate1 "bit_and"

397+ bitOr = unsafeAggregate1 "bit_or"

398+ boolAnd = unsafeAggregate1 "bool_and"

399+ boolOr = unsafeAggregate1 "bool_or"

400+ every = unsafeAggregate1 "every"

401+ max_ = unsafeAggregate1 "max"

402+ min_ = unsafeAggregate1 "min"

403+ avg = unsafeAggregate1 "avg"

404+ corr = unsafeAggregateN "corr"

405+ covarPop = unsafeAggregateN "covar_pop"

406+ covarSamp = unsafeAggregateN "covar_samp"

407+ regrAvgX = unsafeAggregateN "regr_avgx"

408+ regrAvgY = unsafeAggregateN "regr_avgy"

409+ regrCount = unsafeAggregateN "regr_count"

410+ regrIntercept = unsafeAggregateN "regr_intercept"

411+ regrR2 = unsafeAggregateN "regr_r2"

412+ regrSlope = unsafeAggregateN "regr_slope"

413+ regrSxx = unsafeAggregateN "regr_sxx"

414+ regrSxy = unsafeAggregateN "regr_sxy"

415+ regrSyy = unsafeAggregateN "regr_syy"

416+ stddev = unsafeAggregate1 "stddev"

417+ stddevPop = unsafeAggregate1 "stddev_pop"

418+ stddevSamp = unsafeAggregate1 "stddev_samp"

419+ variance = unsafeAggregate1 "variance"

420+ varPop = unsafeAggregate1 "var_pop"

421+ varSamp = unsafeAggregate1 "var_samp"

422+

423+-- | escape hatch to define aggregate functions

424+unsafeAggregate1

425+ :: ByteString -- ^ aggregate function

426+ -> Distinction (Expression outer commons 'Ungrouped schemas params from) x

427+ -> Expression outer commons ('Grouped bys) schemas params from y

428+unsafeAggregate1 fun x = UnsafeExpression $ fun <> parenthesized (renderSQL x)

429+

430+unsafeAggregateN

431+ :: SOP.SListI xs

432+ => ByteString -- ^ function

433+ -> Distinction (NP (Expression outer commons 'Ungrouped schemas params from)) xs

434+ -> Expression outer commons ('Grouped bys) schemas params from y

435+unsafeAggregateN fun xs = UnsafeExpression $ fun <> parenthesized (renderSQL xs)

436+

437+-- | A type family that calculates `PGSum``PGType` of

438+-- a given argument `PGType`.

439+type family PGSum ty where

440+ PGSum 'PGint2 = 'PGint8

441+ PGSum 'PGint4 = 'PGint8

442+ PGSum 'PGint8 = 'PGnumeric

443+ PGSum 'PGfloat4 = 'PGfloat4

444+ PGSum 'PGfloat8 = 'PGfloat8

445+ PGSum 'PGnumeric = 'PGnumeric

446+ PGSum 'PGinterval = 'PGinterval

447+ PGSum 'PGmoney = 'PGmoney

448+ PGSum pg = TypeError

449+ ( 'Text "Squeal type error: Cannot sum with argument type "

450+ ':<>: 'ShowType pg )

451+

452+-- | A type family that calculates `PGAvg` type of a `PGType`.

453+type family PGAvg ty where

454+ PGAvg 'PGint2 = 'PGnumeric

455+ PGAvg 'PGint4 = 'PGnumeric

456+ PGAvg 'PGint8 = 'PGnumeric

457+ PGAvg 'PGnumeric = 'PGnumeric

458+ PGAvg 'PGfloat4 = 'PGfloat8

459+ PGAvg 'PGfloat8 = 'PGfloat8

460+ PGAvg 'PGinterval = 'PGinterval

461+ PGAvg pg = TypeError

462+ ('Text "Squeal type error: No average for " ':<>: 'ShowType pg)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Collection.hsnew file+169

@@ -0,0 +1,169 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Collection

3+Description: Array and composite functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Array and composite functions

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DataKinds

14+ , FlexibleContexts

15+ , FlexibleInstances

16+ , MultiParamTypeClasses

17+ , OverloadedLabels

18+ , OverloadedStrings

19+ , RankNTypes

20+ , ScopedTypeVariables

21+ , TypeApplications

22+ , TypeFamilies

23+ , TypeOperators

24+ , UndecidableInstances

25+#-}

26+

27+module Squeal.PostgreSQL.Expression.Collection

28+ ( array

29+ , array1

30+ , array2

31+ , cardinality

32+ , index

33+ , unnest

34+ , row

35+ , field

36+ ) where

37+

38+import Data.String

39+import Data.Word (Word64)

40+

41+import qualified Generics.SOP as SOP

42+

43+import Squeal.PostgreSQL.Alias

44+import Squeal.PostgreSQL.Expression

45+import Squeal.PostgreSQL.Expression.Set

46+import Squeal.PostgreSQL.List

47+import Squeal.PostgreSQL.Render

48+import Squeal.PostgreSQL.Schema

49+

50+-- $setup

51+-- >>> import Squeal.PostgreSQL

52+

53+-- | >>> printSQL $ array [null_, false, true]

54+-- ARRAY[NULL, FALSE, TRUE]

55+array

56+ :: [Expression outer commons grp schemas params from ty]

57+ -- ^ array elements

58+ -> Expression outer commons grp schemas params from (null ('PGvararray ty))

59+array xs = UnsafeExpression $ "ARRAY" <>

60+ bracketed (commaSeparated (renderSQL <$> xs))

61+

62+{- | construct a 1-dimensional fixed length array

63+

64+>>> printSQL $ array1 (null_ :* false *: true)

65+ARRAY[NULL, FALSE, TRUE]

66+

67+>>> :type array1 (null_ :* false *: true)

68+array1 (null_ :* false *: true)

69+ :: Expression

70+ outer

71+ commons

72+ grp

73+ schemas

74+ params

75+ from

76+ (null ('PGfixarray '[3] ('Null 'PGbool)))

77+-}

78+array1

79+ :: (n ~ Length tys, SOP.All ((~) ty) tys)

80+ => NP (Expression outer commons grp schemas params from) tys

81+ -> Expression outer commons grp schemas params from (null ('PGfixarray '[n] ty))

82+array1 xs = UnsafeExpression $ "ARRAY" <>

83+ bracketed (renderCommaSeparated renderSQL xs)

84+

85+{- | construct a 2-dimensional fixed length array

86+

87+>>> printSQL $ array2 ((null_ :* false *: true) *: (false :* null_ *: true))

88+ARRAY[[NULL, FALSE, TRUE], [FALSE, NULL, TRUE]]

89+

90+>>> :type array2 ((null_ :* false *: true) *: (false :* null_ *: true))

91+array2 ((null_ :* false *: true) *: (false :* null_ *: true))

92+ :: Expression

93+ outer

94+ commons

95+ grp

96+ schemas

97+ params

98+ from

99+ (null ('PGfixarray '[2, 3] ('Null 'PGbool)))

100+-}

101+array2

102+ :: ( SOP.All ((~) tys) tyss

103+ , SOP.All SOP.SListI tyss

104+ , Length tyss ~ n1

105+ , SOP.All ((~) ty) tys

106+ , Length tys ~ n2 )

107+ => NP (NP (Expression outer commons grp schemas params from)) tyss

108+ -> Expression outer commons grp schemas params from (null ('PGfixarray '[n1,n2] ty))

109+array2 xss = UnsafeExpression $ "ARRAY" <>

110+ bracketed (renderCommaSeparatedConstraint @SOP.SListI (bracketed . renderCommaSeparated renderSQL) xss)

111+

112+-- | >>> printSQL $ cardinality (array [null_, false, true])

113+-- cardinality(ARRAY[NULL, FALSE, TRUE])

114+cardinality :: null ('PGvararray ty) --> null 'PGint8

115+cardinality = unsafeFunction "cardinality"

116+

117+-- | >>> printSQL $ array [null_, false, true] & index 2

118+-- (ARRAY[NULL, FALSE, TRUE])[2]

119+index

120+ :: Word64 -- ^ index

121+ -> null ('PGvararray ty) --> NullifyType ty

122+index n expr = UnsafeExpression $

123+ parenthesized (renderSQL expr) <> "[" <> fromString (show n) <> "]"

124+

125+-- | Expand an array to a set of rows

126+unnest :: SetFunction "unnest" (null ('PGvararray ty)) '["unnest" ::: ty]

127+unnest = unsafeSetFunction

128+

129+-- | A row constructor is an expression that builds a row value

130+-- (also called a composite value) using values for its member fields.

131+--

132+-- >>> :{

133+-- type Complex = 'PGcomposite

134+-- '[ "real" ::: 'NotNull 'PGfloat8

135+-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

136+-- :}

137+--

138+-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer commons grp schemas params from ('NotNull Complex)

139+-- >>> printSQL i

140+-- ROW(0, 1)

141+row

142+ :: SOP.SListI row

143+ => NP (Aliased (Expression outer commons grp schemas params from)) row

144+ -- ^ zero or more expressions for the row field values

145+ -> Expression outer commons grp schemas params from (null ('PGcomposite row))

146+row exprs = UnsafeExpression $ "ROW" <> parenthesized

147+ (renderCommaSeparated (\ (expr `As` _) -> renderSQL expr) exprs)

148+

149+-- | >>> :{

150+-- type Complex = 'PGcomposite

151+-- '[ "real" ::: 'NotNull 'PGfloat8

152+-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

153+-- type Schema = '["complex" ::: 'Typedef Complex]

154+-- :}

155+--

156+-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer '[] grp (Public Schema) from params ('NotNull Complex)

157+-- >>> printSQL $ i & field #complex #imaginary

158+-- (ROW(0, 1)::"complex")."imaginary"

159+field

160+ :: ( Has sch schemas schema

161+ , Has tydef schema ('Typedef ('PGcomposite row))

162+ , Has field row ty)

163+ => QualifiedAlias sch tydef -- ^ row type

164+ -> Alias field -- ^ field name

165+ -> Expression outer commons grp schemas params from ('NotNull ('PGcomposite row))

166+ -> Expression outer commons grp schemas params from ty

167+field td fld expr = UnsafeExpression $

168+ parenthesized (renderSQL expr <> "::" <> renderSQL td)

169+ <> "." <> renderSQL fld

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Comparison.hsnew file+206

@@ -0,0 +1,206 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Comparison

3+Description: Comparison expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Comparison functions and operators

9+-}

10+

11+{-# LANGUAGE

12+ OverloadedStrings

13+ , RankNTypes

14+ , TypeInType

15+ , TypeOperators

16+#-}

17+

18+module Squeal.PostgreSQL.Expression.Comparison

19+ ( (.==)

20+ , (./=)

21+ , (.>=)

22+ , (.<)

23+ , (.<=)

24+ , (.>)

25+ , greatest

26+ , least

27+ , BetweenExpr

28+ , between

29+ , notBetween

30+ , betweenSymmetric

31+ , notBetweenSymmetric

32+ , isDistinctFrom

33+ , isNotDistinctFrom

34+ , isTrue

35+ , isNotTrue

36+ , isFalse

37+ , isNotFalse

38+ , isUnknown

39+ , isNotUnknown

40+ ) where

41+

42+import Data.ByteString

43+

44+import Squeal.PostgreSQL.Expression

45+import Squeal.PostgreSQL.Expression.Logic

46+import Squeal.PostgreSQL.Render

47+import Squeal.PostgreSQL.Schema

48+

49+-- $setup

50+-- >>> import Squeal.PostgreSQL

51+

52+-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`

53+-- will produce @NULL@s if one of their arguments is @NULL@.

54+--

55+-- >>> printSQL $ true .== null_

56+-- (TRUE = NULL)

57+(.==) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

58+(.==) = unsafeBinaryOp "="

59+infix 4 .==

60+

61+-- | >>> printSQL $ true ./= null_

62+-- (TRUE <> NULL)

63+(./=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

64+(./=) = unsafeBinaryOp "<>"

65+infix 4 ./=

66+

67+-- | >>> printSQL $ true .>= null_

68+-- (TRUE >= NULL)

69+(.>=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

70+(.>=) = unsafeBinaryOp ">="

71+infix 4 .>=

72+

73+-- | >>> printSQL $ true .< null_

74+-- (TRUE < NULL)

75+(.<) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

76+(.<) = unsafeBinaryOp "<"

77+infix 4 .<

78+

79+-- | >>> printSQL $ true .<= null_

80+-- (TRUE <= NULL)

81+(.<=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

82+(.<=) = unsafeBinaryOp "<="

83+infix 4 .<=

84+

85+-- | >>> printSQL $ true .> null_

86+-- (TRUE > NULL)

87+(.>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

88+(.>) = unsafeBinaryOp ">"

89+infix 4 .>

90+

91+-- | >>> let expr = greatest [param @1] currentTimestamp :: Expression outer commons grp schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)

92+-- >>> printSQL expr

93+-- GREATEST(($1 :: timestamp with time zone), CURRENT_TIMESTAMP)

94+greatest :: FunctionVar ty ty ty

95+greatest = unsafeFunctionVar "GREATEST"

96+

97+-- | >>> printSQL $ least [null_] currentTimestamp

98+-- LEAST(NULL, CURRENT_TIMESTAMP)

99+least :: FunctionVar ty ty ty

100+least = unsafeFunctionVar "LEAST"

101+

102+{- |

103+A @RankNType@ for comparison expressions like `between`.

104+-}

105+type BetweenExpr

106+ = forall outer commons grp schemas params from ty

107+ . Expression outer commons grp schemas params from ty

108+ -> ( Expression outer commons grp schemas params from ty

109+ , Expression outer commons grp schemas params from ty ) -- ^ bounds

110+ -> Condition outer commons grp schemas params from

111+

112+unsafeBetweenExpr :: ByteString -> BetweenExpr

113+unsafeBetweenExpr fun a (x,y) = UnsafeExpression $

114+ renderSQL a <+> fun <+> renderSQL x <+> "AND" <+> renderSQL y

115+

116+{- | >>> printSQL $ true `between` (null_, false)

117+TRUE BETWEEN NULL AND FALSE

118+-}

119+between :: BetweenExpr

120+between = unsafeBetweenExpr "BETWEEN"

121+

122+{- | >>> printSQL $ true `notBetween` (null_, false)

123+TRUE NOT BETWEEN NULL AND FALSE

124+-}

125+notBetween :: BetweenExpr

126+notBetween = unsafeBetweenExpr "NOT BETWEEN"

127+

128+{- | between, after sorting the comparison values

129+

130+>>> printSQL $ true `betweenSymmetric` (null_, false)

131+TRUE BETWEEN SYMMETRIC NULL AND FALSE

132+-}

133+betweenSymmetric :: BetweenExpr

134+betweenSymmetric = unsafeBetweenExpr "BETWEEN SYMMETRIC"

135+

136+{- | not between, after sorting the comparison values

137+

138+>>> printSQL $ true `notBetweenSymmetric` (null_, false)

139+TRUE NOT BETWEEN SYMMETRIC NULL AND FALSE

140+-}

141+notBetweenSymmetric :: BetweenExpr

142+notBetweenSymmetric = unsafeBetweenExpr "NOT BETWEEN SYMMETRIC"

143+

144+{- | not equal, treating null like an ordinary value

145+

146+>>> printSQL $ true `isDistinctFrom` null_

147+(TRUE IS DISTINCT FROM NULL)

148+-}

149+isDistinctFrom :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

150+isDistinctFrom = unsafeBinaryOp "IS DISTINCT FROM"

151+

152+{- | equal, treating null like an ordinary value

153+

154+>>> printSQL $ true `isNotDistinctFrom` null_

155+(TRUE IS NOT DISTINCT FROM NULL)

156+-}

157+isNotDistinctFrom :: Operator (null0 ty) (null1 ty) ('NotNull 'PGbool)

158+isNotDistinctFrom = unsafeBinaryOp "IS NOT DISTINCT FROM"

159+

160+{- | is true

161+

162+>>> printSQL $ true & isTrue

163+(TRUE IS TRUE)

164+-}

165+isTrue :: null0 'PGbool --> null1 'PGbool

166+isTrue = unsafeRightOp "IS TRUE"

167+

168+{- | is false or unknown

169+

170+>>> printSQL $ true & isNotTrue

171+(TRUE IS NOT TRUE)

172+-}

173+isNotTrue :: null0 'PGbool --> null1 'PGbool

174+isNotTrue = unsafeRightOp "IS NOT TRUE"

175+

176+{- | is false

177+

178+>>> printSQL $ true & isFalse

179+(TRUE IS FALSE)

180+-}

181+isFalse :: null0 'PGbool --> null1 'PGbool

182+isFalse = unsafeRightOp "IS FALSE"

183+

184+{- | is true or unknown

185+

186+>>> printSQL $ true & isNotFalse

187+(TRUE IS NOT FALSE)

188+-}

189+isNotFalse :: null0 'PGbool --> null1 'PGbool

190+isNotFalse = unsafeRightOp "IS NOT FALSE"

191+

192+{- | is unknown

193+

194+>>> printSQL $ true & isUnknown

195+(TRUE IS UNKNOWN)

196+-}

197+isUnknown :: null0 'PGbool --> null1 'PGbool

198+isUnknown = unsafeRightOp "IS UNKNOWN"

199+

200+{- | is true or false

201+

202+>>> printSQL $ true & isNotUnknown

203+(TRUE IS NOT UNKNOWN)

204+-}

205+isNotUnknown :: null0 'PGbool --> null1 'PGbool

206+isNotUnknown = unsafeRightOp "IS NOT UNKNOWN"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Json.hsnew file+462

@@ -0,0 +1,462 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Json

3+Description: Json and Jsonb functions and operators

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Json and Jsonb functions and operators

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , FlexibleContexts

14+ , FlexibleInstances

15+ , GADTs

16+ , OverloadedLabels

17+ , OverloadedStrings

18+ , PolyKinds

19+ , RankNTypes

20+ , ScopedTypeVariables

21+ , TypeApplications

22+ , TypeOperators

23+ , UndecidableInstances

24+ , UndecidableSuperClasses

25+#-}

26+

27+module Squeal.PostgreSQL.Expression.Json

28+ ( -- * Json and Jsonb operators

29+ (.->)

30+ , (.->>)

31+ , (.#>)

32+ , (.#>>)

33+ -- * Jsonb operators

34+ , (.?)

35+ , (.?|)

36+ , (.?&)

37+ , (.-.)

38+ , (#-.)

39+ -- * Json and Jsonb functions

40+ , toJson

41+ , toJsonb

42+ , arrayToJson

43+ , rowToJson

44+ , jsonBuildArray

45+ , jsonbBuildArray

46+ , JsonBuildObject (..)

47+ , jsonObject

48+ , jsonbObject

49+ , jsonZipObject

50+ , jsonbZipObject

51+ , jsonArrayLength

52+ , jsonbArrayLength

53+ , jsonTypeof

54+ , jsonbTypeof

55+ , jsonStripNulls

56+ , jsonbStripNulls

57+ , jsonbSet

58+ , jsonbInsert

59+ , jsonbPretty

60+ -- * Json and Jsonb set returning functions

61+ , jsonEach

62+ , jsonbEach

63+ , jsonEachText

64+ , jsonbEachText

65+ , jsonObjectKeys

66+ , jsonbObjectKeys

67+ , JsonPopulateFunction

68+ , jsonPopulateRecord

69+ , jsonbPopulateRecord

70+ , jsonPopulateRecordSet

71+ , jsonbPopulateRecordSet

72+ , JsonToRecordFunction

73+ , jsonToRecord

74+ , jsonbToRecord

75+ , jsonToRecordSet

76+ , jsonbToRecordSet

77+ ) where

78+

79+import Data.ByteString (ByteString)

80+import GHC.TypeLits

81+

82+import Squeal.PostgreSQL.Alias

83+import Squeal.PostgreSQL.Expression

84+import Squeal.PostgreSQL.Expression.Set

85+import Squeal.PostgreSQL.Expression.Type

86+import Squeal.PostgreSQL.List

87+import Squeal.PostgreSQL.Query

88+import Squeal.PostgreSQL.Render

89+import Squeal.PostgreSQL.Schema

90+

91+import qualified Generics.SOP as SOP

92+

93+-- $setup

94+-- >>> import Squeal.PostgreSQL

95+-- >>> import Data.Aeson

96+

97+{-----------------------------------------

98+ -- json and jsonb support

99+

100+See https://www.postgresql.org/docs/10/static/functions-json.html -- most

101+comments lifted directly from this page.

102+

103+Table 9.44: json and jsonb operators

104+-----------------------------------------}

105+

106+-- | Get JSON value (object field or array element) at a key.

107+(.->)

108+ :: (json `In` PGJsonType, key `In` PGJsonKey)

109+ => Operator (null json) (null key) ('Null json)

110+infixl 8 .->

111+(.->) = unsafeBinaryOp "->"

112+

113+-- | Get JSON value (object field or array element) at a key, as text.

114+(.->>)

115+ :: (json `In` PGJsonType, key `In` PGJsonKey)

116+ => Operator (null json) (null key) ('Null 'PGtext)

117+infixl 8 .->>

118+(.->>) = unsafeBinaryOp "->>"

119+

120+-- | Get JSON value at a specified path.

121+(.#>)

122+ :: json `In` PGJsonType

123+ => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null json)

124+infixl 8 .#>

125+(.#>) = unsafeBinaryOp "#>"

126+

127+-- | Get JSON value at a specified path as text.

128+(.#>>)

129+ :: json `In` PGJsonType

130+ => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null 'PGtext)

131+infixl 8 .#>>

132+(.#>>) = unsafeBinaryOp "#>>"

133+

134+-- Additional jsonb operators

135+

136+-- | Does the string exist as a top-level key within the JSON value?

137+(.?) :: Operator (null 'PGjsonb) (null 'PGtext) ('Null 'PGbool)

138+infixl 9 .?

139+(.?) = unsafeBinaryOp "?"

140+

141+-- | Do any of these array strings exist as top-level keys?

142+(.?|) :: Operator

143+ (null 'PGjsonb)

144+ (null ('PGvararray ('NotNull 'PGtext)))

145+ ('Null 'PGbool)

146+infixl 9 .?|

147+(.?|) = unsafeBinaryOp "?|"

148+

149+-- | Do all of these array strings exist as top-level keys?

150+(.?&) :: Operator

151+ (null 'PGjsonb)

152+ (null ('PGvararray ('NotNull 'PGtext)))

153+ ('Null 'PGbool)

154+infixl 9 .?&

155+(.?&) = unsafeBinaryOp "?&"

156+

157+-- | Delete a key or keys from a JSON object, or remove an array element.

158+--

159+-- If the right operand is

160+--

161+-- @ text @: Delete key / value pair or string element from left operand.

162+-- Key / value pairs are matched based on their key value,

163+--

164+-- @ text[] @: Delete multiple key / value pairs or string elements

165+-- from left operand. Key / value pairs are matched based on their key value,

166+--

167+-- @ integer @: Delete the array element with specified index (Negative integers

168+-- count from the end). Throws an error if top level container is not an array.

169+(.-.)

170+ :: key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]

171+ => Operator (null 'PGjsonb) (null key) (null 'PGjsonb)

172+infixl 6 .-.

173+(.-.) = unsafeBinaryOp "-"

174+

175+-- | Delete the field or element with specified path (for JSON arrays, negative

176+-- integers count from the end)

177+(#-.) :: Operator (null 'PGjsonb) (null ('PGvararray ('NotNull 'PGtext))) (null 'PGjsonb)

178+infixl 6 #-.

179+(#-.) = unsafeBinaryOp "#-"

180+

181+{-----------------------------------------

182+Table 9.45: JSON creation functions

183+-----------------------------------------}

184+

185+-- | Returns the value as json. Arrays and composites are converted

186+-- (recursively) to arrays and objects; otherwise, if there is a cast from the

187+-- type to json, the cast function will be used to perform the conversion;

188+-- otherwise, a scalar value is produced. For any scalar type other than a

189+-- number, a Boolean, or a null value, the text representation will be used, in

190+-- such a fashion that it is a valid json value.

191+toJson :: null ty --> null 'PGjson

192+toJson = unsafeFunction "to_json"

193+

194+-- | Returns the value as jsonb. Arrays and composites are converted

195+-- (recursively) to arrays and objects; otherwise, if there is a cast from the

196+-- type to json, the cast function will be used to perform the conversion;

197+-- otherwise, a scalar value is produced. For any scalar type other than a

198+-- number, a Boolean, or a null value, the text representation will be used, in

199+-- such a fashion that it is a valid jsonb value.

200+toJsonb :: null ty --> null 'PGjsonb

201+toJsonb = unsafeFunction "to_jsonb"

202+

203+-- | Returns the array as a JSON array. A PostgreSQL multidimensional array

204+-- becomes a JSON array of arrays.

205+arrayToJson :: null ('PGvararray ty) --> null 'PGjson

206+arrayToJson = unsafeFunction "array_to_json"

207+

208+-- | Returns the row as a JSON object.

209+rowToJson :: null ('PGcomposite ty) --> null 'PGjson

210+rowToJson = unsafeFunction "row_to_json"

211+

212+-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic

213+-- argument list.

214+jsonBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjson

215+jsonBuildArray = unsafeFunctionN "json_build_array"

216+

217+-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a

218+-- variadic argument list.

219+jsonbBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjsonb

220+jsonbBuildArray = unsafeFunctionN "jsonb_build_array"

221+

222+-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic

223+-- argument list. The elements of the argument list must alternate between text

224+-- and values.

225+class SOP.SListI tys => JsonBuildObject tys where

226+

227+ jsonBuildObject :: tys ---> null 'PGjson

228+ jsonBuildObject = unsafeFunctionN "json_build_object"

229+

230+ jsonbBuildObject :: tys ---> null 'PGjsonb

231+ jsonbBuildObject = unsafeFunctionN "jsonb_build_object"

232+

233+instance JsonBuildObject '[]

234+instance (JsonBuildObject tys, key `In` PGJsonKey)

235+ => JsonBuildObject ('NotNull key ': value ': tys)

236+

237+-- | Builds a JSON object out of a text array.

238+-- The array must have two dimensions

239+-- such that each inner array has exactly two elements,

240+-- which are taken as a key/value pair.

241+jsonObject

242+ :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))

243+ --> null 'PGjson

244+jsonObject = unsafeFunction "json_object"

245+

246+-- | Builds a binary JSON object out of a text array.

247+-- The array must have two dimensions

248+-- such that each inner array has exactly two elements,

249+-- which are taken as a key/value pair.

250+jsonbObject

251+ :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))

252+ --> null 'PGjsonb

253+jsonbObject = unsafeFunction "jsonb_object"

254+

255+-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

256+-- keys and one for values, that are zipped pairwise to create a JSON object.

257+jsonZipObject ::

258+ '[ null ('PGvararray ('NotNull 'PGtext))

259+ , null ('PGvararray ('NotNull 'PGtext)) ]

260+ ---> null 'PGjson

261+jsonZipObject = unsafeFunctionN "json_object"

262+

263+-- | This is an alternate form of 'jsonbObject' that takes two arrays; one for

264+-- keys and one for values, that are zipped pairwise to create a binary JSON

265+-- object.

266+jsonbZipObject ::

267+ '[ null ('PGvararray ('NotNull 'PGtext))

268+ , null ('PGvararray ('NotNull 'PGtext)) ]

269+ ---> null 'PGjsonb

270+jsonbZipObject = unsafeFunctionN "jsonb_object"

271+

272+{-----------------------------------------

273+Table 9.46: JSON processing functions

274+-----------------------------------------}

275+

276+-- | Returns the number of elements in the outermost JSON array.

277+jsonArrayLength :: null 'PGjson --> null 'PGint4

278+jsonArrayLength = unsafeFunction "json_array_length"

279+

280+-- | Returns the number of elements in the outermost binary JSON array.

281+jsonbArrayLength :: null 'PGjsonb --> null 'PGint4

282+jsonbArrayLength = unsafeFunction "jsonb_array_length"

283+

284+-- | Returns the type of the outermost JSON value as a text string. Possible

285+-- types are object, array, string, number, boolean, and null.

286+jsonTypeof :: null 'PGjson --> null 'PGtext

287+jsonTypeof = unsafeFunction "json_typeof"

288+

289+-- | Returns the type of the outermost binary JSON value as a text string.

290+-- Possible types are object, array, string, number, boolean, and null.

291+jsonbTypeof :: null 'PGjsonb --> null 'PGtext

292+jsonbTypeof = unsafeFunction "jsonb_typeof"

293+

294+-- | Returns its argument with all object fields that have null values omitted.

295+-- Other null values are untouched.

296+jsonStripNulls :: null 'PGjson --> null 'PGjson

297+jsonStripNulls = unsafeFunction "json_strip_nulls"

298+

299+-- | Returns its argument with all object fields that have null values omitted.

300+-- Other null values are untouched.

301+jsonbStripNulls :: null 'PGjsonb --> null 'PGjsonb

302+jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"

303+

304+-- | @ jsonbSet target path new_value create_missing @

305+--

306+-- Returns target with the section designated by path replaced by @new_value@,

307+-- or with @new_value@ added if create_missing is

308+-- `Squeal.PostgreSQL.Expression.Logic.true` and the

309+-- item designated by path does not exist. As with the path orientated

310+-- operators, negative integers that appear in path count from the end of JSON

311+-- arrays.

312+jsonbSet ::

313+ '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))

314+ , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb

315+jsonbSet = unsafeFunctionN "jsonbSet"

316+

317+-- | @ jsonbInsert target path new_value insert_after @

318+--

319+-- Returns target with @new_value@ inserted. If target section designated by

320+-- path is in a JSONB array, @new_value@ will be inserted before target or after

321+-- if @insert_after@ is `Squeal.PostgreSQL.Expression.Logic.true`.

322+-- If target section designated by

323+-- path is in JSONB object, @new_value@ will be inserted only if target does not

324+-- exist. As with the path orientated operators, negative integers that appear

325+-- in path count from the end of JSON arrays.

326+jsonbInsert ::

327+ '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))

328+ , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb

329+jsonbInsert = unsafeFunctionN "jsonb_insert"

330+

331+-- | Returns its argument as indented JSON text.

332+jsonbPretty :: null 'PGjsonb --> null 'PGtext

333+jsonbPretty = unsafeFunction "jsonb_pretty"

334+

335+{- | Expands the outermost JSON object into a set of key/value pairs.

336+

337+>>> printSQL (select Star (from (jsonEach (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

338+SELECT * FROM json_each(('{"a":"foo","b":"bar"}' :: json))

339+-}

340+jsonEach :: SetFunction "json_each" (null 'PGjson)

341+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

342+jsonEach = unsafeSetFunction

343+

344+{- | Expands the outermost binary JSON object into a set of key/value pairs.

345+

346+>>> printSQL (select Star (from (jsonbEach (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

347+SELECT * FROM jsonb_each(('{"a":"foo","b":"bar"}' :: jsonb))

348+-}

349+jsonbEach

350+ :: SetFunction "jsonb_each" (nullity 'PGjsonb)

351+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

352+jsonbEach = unsafeSetFunction

353+

354+{- | Expands the outermost JSON object into a set of key/value pairs.

355+

356+>>> printSQL (select Star (from (jsonEachText (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

357+SELECT * FROM json_each_text(('{"a":"foo","b":"bar"}' :: json))

358+-}

359+jsonEachText

360+ :: SetFunction "json_each_text" (null 'PGjson)

361+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

362+jsonEachText = unsafeSetFunction

363+

364+{- | Expands the outermost binary JSON object into a set of key/value pairs.

365+

366+>>> printSQL (select Star (from (jsonbEachText (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

367+SELECT * FROM jsonb_each_text(('{"a":"foo","b":"bar"}' :: jsonb))

368+-}

369+jsonbEachText

370+ :: SetFunction "jsonb_each_text" (null 'PGjsonb)

371+ '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

372+jsonbEachText = unsafeSetFunction

373+

374+{- | Returns set of keys in the outermost JSON object.

375+

376+>>> printSQL (jsonObjectKeys (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))

377+json_object_keys(('{"a":"foo","b":"bar"}' :: json))

378+-}

379+jsonObjectKeys

380+ :: SetFunction "json_object_keys" (nullity 'PGjson)

381+ '["json_object_keys" ::: 'NotNull 'PGtext]

382+jsonObjectKeys = unsafeSetFunction

383+

384+{- | Returns set of keys in the outermost JSON object.

385+

386+>>> printSQL (jsonbObjectKeys (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))

387+jsonb_object_keys(('{"a":"foo","b":"bar"}' :: jsonb))

388+-}

389+jsonbObjectKeys

390+ :: SetFunction "jsonb_object_keys" (null 'PGjsonb)

391+ '["jsonb_object_keys" ::: 'NotNull 'PGtext]

392+jsonbObjectKeys = unsafeSetFunction

393+

394+-- | Build rows from Json types.

395+type JsonPopulateFunction fun json

396+ = forall schemas row outer commons params

397+ . json `In` PGJsonType

398+ => TypeExpression schemas ('NotNull ('PGcomposite row)) -- ^ row type

399+ -> Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

400+ -- ^ json type

401+ -> FromClause outer commons schemas params '[fun ::: row]

402+

403+unsafePopulateFunction

404+ :: forall fun ty

405+ . KnownSymbol fun => Alias fun -> JsonPopulateFunction fun ty

406+unsafePopulateFunction _fun ty expr = UnsafeFromClause $ renderSymbol @fun

407+ <> parenthesized ("null::" <> renderSQL ty <> ", " <> renderSQL expr)

408+

409+-- | Expands the JSON expression to a row whose columns match the record

410+-- type defined by the given table.

411+jsonPopulateRecord :: JsonPopulateFunction "json_populate_record" 'PGjson

412+jsonPopulateRecord = unsafePopulateFunction #json_populate_record

413+

414+-- | Expands the binary JSON expression to a row whose columns match the record

415+-- type defined by the given table.

416+jsonbPopulateRecord :: JsonPopulateFunction "jsonb_populate_record" 'PGjsonb

417+jsonbPopulateRecord = unsafePopulateFunction #jsonb_populate_record

418+

419+-- | Expands the outermost array of objects in the given JSON expression to a

420+-- set of rows whose columns match the record type defined by the given table.

421+jsonPopulateRecordSet :: JsonPopulateFunction "json_populate_record_set" 'PGjson

422+jsonPopulateRecordSet = unsafePopulateFunction #json_populate_record_set

423+

424+-- | Expands the outermost array of objects in the given binary JSON expression

425+-- to a set of rows whose columns match the record type defined by the given

426+-- table.

427+jsonbPopulateRecordSet :: JsonPopulateFunction "jsonb_populate_record_set" 'PGjsonb

428+jsonbPopulateRecordSet = unsafePopulateFunction #jsonb_populate_record_set

429+

430+-- | Build rows from Json types.

431+type JsonToRecordFunction json

432+ = forall outer commons schemas params tab row

433+ . (SOP.SListI row, json `In` PGJsonType)

434+ => Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

435+ -- ^ json type

436+ -> Aliased (NP (Aliased (TypeExpression schemas))) (tab ::: row)

437+ -- ^ row type

438+ -> FromClause outer commons schemas params '[tab ::: row]

439+

440+unsafeRecordFunction :: ByteString -> JsonToRecordFunction json

441+unsafeRecordFunction fun expr (types `As` tab) = UnsafeFromClause $

442+ fun <> parenthesized (renderSQL expr) <+> "AS" <+> renderSQL tab

443+ <> parenthesized (renderCommaSeparated renderTy types)

444+ where

445+ renderTy :: Aliased (TypeExpression schemas) ty -> ByteString

446+ renderTy (ty `As` alias) = renderSQL alias <+> renderSQL ty

447+

448+-- | Builds an arbitrary record from a JSON object.

449+jsonToRecord :: JsonToRecordFunction 'PGjson

450+jsonToRecord = unsafeRecordFunction "json_to_record"

451+

452+-- | Builds an arbitrary record from a binary JSON object.

453+jsonbToRecord :: JsonToRecordFunction 'PGjsonb

454+jsonbToRecord = unsafeRecordFunction "jsonb_to_record"

455+

456+-- | Builds an arbitrary set of records from a JSON array of objects.

457+jsonToRecordSet :: JsonToRecordFunction 'PGjson

458+jsonToRecordSet = unsafeRecordFunction "json_to_record_set"

459+

460+-- | Builds an arbitrary set of records from a binary JSON array of objects.

461+jsonbToRecordSet :: JsonToRecordFunction 'PGjsonb

462+jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Literal.hsnew file+87

@@ -0,0 +1,87 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Literal

3+Description: Literal expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

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_ = unsafeLeftOp "NOT"

52+

53+-- | >>> printSQL $ true .&& false

54+-- (TRUE AND FALSE)

55+(.&&) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)

56+infixr 3 .&&

57+(.&&) = unsafeBinaryOp "AND"

58+

59+-- | >>> printSQL $ true .|| false

60+-- (TRUE OR FALSE)

61+(.||) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)

62+infixr 2 .||

63+(.||) = unsafeBinaryOp "OR"

64+

65+-- | >>> :{

66+-- let

67+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

68+-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3

69+-- in printSQL expression

70+-- :}

71+-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END

72+caseWhenThenElse

73+ :: [ ( Condition outer commons grp schemas params from

74+ , Expression outer commons grp schemas params from ty

75+ ) ]

76+ -- ^ whens and thens

77+ -> Expression outer commons grp schemas params from ty

78+ -- ^ else

79+ -> Expression outer commons grp schemas params from ty

80+caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat

81+ [ "CASE"

82+ , mconcat

83+ [ mconcat

84+ [ " WHEN ", renderSQL when_

85+ , " THEN ", renderSQL then_

86+ ]

87+ | (when_,then_) <- whenThens

88+ ]

89+ , " ELSE ", renderSQL else_

90+ , " END"

91+ ]

92+

93+-- | >>> :{

94+-- let

95+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

96+-- expression = ifThenElse true 1 0

97+-- in printSQL expression

98+-- :}

99+-- CASE WHEN TRUE THEN 1 ELSE 0 END

100+ifThenElse

101+ :: Condition outer commons grp schemas params from

102+ -> Expression outer commons grp schemas params from ty -- ^ then

103+ -> Expression outer commons grp schemas params from ty -- ^ else

104+ -> Expression outer commons grp schemas params from ty

105+ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Math.hsnew file+100

@@ -0,0 +1,100 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Math

3+Description: Math expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Mathematical functions and operators

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , OverloadedStrings

14+ , TypeOperators

15+#-}

16+

17+module Squeal.PostgreSQL.Expression.Math

18+ ( atan2_

19+ , quot_

20+ , rem_

21+ , trunc

22+ , round_

23+ , ceiling_

24+ ) where

25+

26+import Squeal.PostgreSQL.Expression

27+import Squeal.PostgreSQL.List

28+import Squeal.PostgreSQL.Schema

29+

30+-- $setup

31+-- >>> import Squeal.PostgreSQL

32+

33+-- | >>> :{

34+-- let

35+-- expression :: Expr (null 'PGfloat4)

36+-- expression = atan2_ (pi *: 2)

37+-- in printSQL expression

38+-- :}

39+-- atan2(pi(), 2)

40+atan2_ :: float `In` PGFloating => '[ null float, null float] ---> null float

41+atan2_ = unsafeFunctionN "atan2"

42+

43+

44+-- | integer division, truncates the result

45+--

46+-- >>> :{

47+-- let

48+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

49+-- expression = 5 `quot_` 2

50+-- in printSQL expression

51+-- :}

52+-- (5 / 2)

53+quot_

54+ :: int `In` PGIntegral

55+ => Operator (null int) (null int) (null int)

56+quot_ = unsafeBinaryOp "/"

57+

58+-- | remainder upon integer division

59+--

60+-- >>> :{

61+-- let

62+-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

63+-- expression = 5 `rem_` 2

64+-- in printSQL expression

65+-- :}

66+-- (5 % 2)

67+rem_

68+ :: int `In` PGIntegral

69+ => Operator (null int) (null int) (null int)

70+rem_ = unsafeBinaryOp "%"

71+

72+-- | >>> :{

73+-- let

74+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

75+-- expression = trunc pi

76+-- in printSQL expression

77+-- :}

78+-- trunc(pi())

79+trunc :: frac `In` PGFloating => null frac --> null frac

80+trunc = unsafeFunction "trunc"

81+

82+-- | >>> :{

83+-- let

84+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

85+-- expression = round_ pi

86+-- in printSQL expression

87+-- :}

88+-- round(pi())

89+round_ :: frac `In` PGFloating => null frac --> null frac

90+round_ = unsafeFunction "round"

91+

92+-- | >>> :{

93+-- let

94+-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

95+-- expression = ceiling_ pi

96+-- in printSQL expression

97+-- :}

98+-- ceiling(pi())

99+ceiling_ :: frac `In` PGFloating => null frac --> null frac

100+ceiling_ = unsafeFunction "ceiling"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Null.hsnew file+104

@@ -0,0 +1,104 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Null

3+Description: Null

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Null values and null handling functions

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , OverloadedStrings

14+ , TypeOperators

15+#-}

16+

17+module Squeal.PostgreSQL.Expression.Null

18+ ( null_

19+ , notNull

20+ , coalesce

21+ , fromNull

22+ , isNull

23+ , isNotNull

24+ , matchNull

25+ , nullIf

26+ ) where

27+

28+import Squeal.PostgreSQL.Expression

29+import Squeal.PostgreSQL.Expression.Logic

30+import Squeal.PostgreSQL.Render

31+import Squeal.PostgreSQL.Schema

32+

33+-- $setup

34+-- >>> import Squeal.PostgreSQL

35+

36+-- | analagous to `Nothing`

37+--

38+-- >>> printSQL null_

39+-- NULL

40+null_ :: Expr ('Null ty)

41+null_ = UnsafeExpression "NULL"

42+

43+-- | analagous to `Just`

44+--

45+-- >>> printSQL $ notNull true

46+-- TRUE

47+notNull :: 'NotNull ty --> 'Null ty

48+notNull = UnsafeExpression . renderSQL

49+

50+-- | return the leftmost value which is not NULL

51+--

52+-- >>> printSQL $ coalesce [null_, true] false

53+-- COALESCE(NULL, TRUE, FALSE)

54+coalesce :: FunctionVar ('Null ty) ('NotNull ty) ('NotNull ty)

55+coalesce nullxs notNullx = UnsafeExpression $

56+ "COALESCE" <> parenthesized (commaSeparated

57+ ((renderSQL <$> nullxs) <> [renderSQL notNullx]))

58+

59+-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@

60+--

61+-- >>> printSQL $ fromNull true null_

62+-- COALESCE(NULL, TRUE)

63+fromNull

64+ :: Expression outer commons grp schemas params from ('NotNull ty)

65+ -- ^ what to convert @NULL@ to

66+ -> Expression outer commons grp schemas params from ('Null ty)

67+ -> Expression outer commons grp schemas params from ('NotNull ty)

68+fromNull notNullx nullx = coalesce [nullx] notNullx

69+

70+-- | >>> printSQL $ null_ & isNull

71+-- NULL IS NULL

72+isNull :: 'Null ty --> null 'PGbool

73+isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"

74+

75+-- | >>> printSQL $ null_ & isNotNull

76+-- NULL IS NOT NULL

77+isNotNull :: 'Null ty --> null 'PGbool

78+isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"

79+

80+-- | analagous to `maybe` using @IS NULL@

81+--

82+-- >>> printSQL $ matchNull true not_ null_

83+-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END

84+matchNull

85+ :: Expression outer commons grp schemas params from (nullty)

86+ -- ^ what to convert @NULL@ to

87+ -> ( Expression outer commons grp schemas params from ('NotNull ty)

88+ -> Expression outer commons grp schemas params from (nullty) )

89+ -- ^ function to perform when @NULL@ is absent

90+ -> Expression outer commons grp schemas params from ('Null ty)

91+ -> Expression outer commons grp schemas params from (nullty)

92+matchNull y f x = ifThenElse (isNull x) y

93+ (f (UnsafeExpression (renderSQL x)))

94+

95+{-| right inverse to `fromNull`, if its arguments are equal then

96+`nullIf` gives @NULL@.

97+

98+>>> :set -XTypeApplications -XDataKinds

99+>>> let expr = nullIf (false *: param @1) :: Expression outer commons grp schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)

100+>>> printSQL expr

101+NULLIF(FALSE, ($1 :: bool))

102+-}

103+nullIf :: '[ 'NotNull ty, 'NotNull ty] ---> 'Null ty

104+nullIf = unsafeFunctionN "NULLIF"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Parameter.hsnew file+80

@@ -0,0 +1,80 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Parameter

3+Description: Parameters

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Parameters, out-of-line data values

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DataKinds

14+ , FlexibleContexts

15+ , FlexibleInstances

16+ , FunctionalDependencies

17+ , KindSignatures

18+ , MultiParamTypeClasses

19+ , OverloadedStrings

20+ , RankNTypes

21+ , ScopedTypeVariables

22+ , TypeApplications

23+ , TypeOperators

24+ , UndecidableInstances

25+#-}

26+

27+module Squeal.PostgreSQL.Expression.Parameter

28+ ( HasParameter (parameter)

29+ , param

30+ ) where

31+

32+import GHC.TypeLits

33+

34+import Squeal.PostgreSQL.Expression

35+import Squeal.PostgreSQL.Expression.Type

36+import Squeal.PostgreSQL.Render

37+import Squeal.PostgreSQL.Schema

38+

39+-- $setup

40+-- >>> import Squeal.PostgreSQL

41+

42+{- | A `HasParameter` constraint is used to indicate a value that is

43+supplied externally to a SQL statement.

44+`Squeal.PostgreSQL.PQ.manipulateParams`,

45+`Squeal.PostgreSQL.PQ.queryParams` and

46+`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values

47+separately from the SQL command string, in which case `param`s are used to

48+refer to the out-of-line data values.

49+-}

50+class KnownNat n => HasParameter

51+ (n :: Nat)

52+ (params :: [NullityType])

53+ (ty :: NullityType)

54+ | n params -> ty where

55+ -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.

56+ --

57+ -- >>> let expr = parameter @1 int4 :: Expression outer '[] grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

58+ -- >>> printSQL expr

59+ -- ($1 :: int4)

60+ parameter

61+ :: TypeExpression schemas ty

62+ -> Expression outer commons grp schemas params from ty

63+ parameter ty = UnsafeExpression $ parenthesized $

64+ "$" <> renderNat @n <+> "::"

65+ <+> renderSQL ty

66+instance {-# OVERLAPPING #-} HasParameter 1 (ty1:tys) ty1

67+instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)

68+ => HasParameter n (ty' : params) ty

69+

70+-- | `param` takes a `Nat` using type application and for basic types,

71+-- infers a `TypeExpression`.

72+--

73+-- >>> let expr = param @1 :: Expression outer commons grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

74+-- >>> printSQL expr

75+-- ($1 :: int4)

76+param

77+ :: forall n outer commons schemas params from grp ty

78+ . (PGTyped schemas ty, HasParameter n params ty)

79+ => Expression outer commons grp schemas params from ty -- ^ param

80+param = parameter @n (pgtype @schemas)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Range.hsnew file+230

@@ -0,0 +1,230 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Range

3+Description: range types and functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Range types and functions

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DataKinds

14+ , DeriveAnyClass

15+ , DeriveGeneric

16+ , DeriveFoldable

17+ , DerivingStrategies

18+ , DeriveTraversable

19+ , FlexibleContexts

20+ , FlexibleInstances

21+ , LambdaCase

22+ , MultiParamTypeClasses

23+ , OverloadedLabels

24+ , OverloadedStrings

25+ , PatternSynonyms

26+ , RankNTypes

27+ , ScopedTypeVariables

28+ , TypeApplications

29+ , TypeFamilies

30+ , TypeOperators

31+ , UndecidableInstances

32+#-}

33+

34+module Squeal.PostgreSQL.Expression.Range

35+ ( range

36+ , Range (..)

37+ , (<=..<=), (<..<), (<=..<), (<..<=)

38+ , moreThan, atLeast, lessThan, atMost

39+ , singleton, whole

40+ , Bound (..)

41+ , (.<@)

42+ , (@>.)

43+ , (<<@)

44+ , (@>>)

45+ , (&<)

46+ , (&>)

47+ , (-|-)

48+ , (@+)

49+ , (@*)

50+ , (@-)

51+ , lowerBound

52+ , upperBound

53+ , isEmpty

54+ , lowerInc

55+ , lowerInf

56+ , upperInc

57+ , upperInf

58+ , rangeMerge

59+ ) where

60+

61+import BinaryParser

62+import ByteString.StrictBuilder

63+import Data.Bits

64+import qualified GHC.Generics as GHC

65+import qualified Generics.SOP as SOP

66+import qualified PostgreSQL.Binary.Decoding as Decoding

67+

68+import Squeal.PostgreSQL.Binary

69+import Squeal.PostgreSQL.Expression

70+import Squeal.PostgreSQL.Expression.Type hiding (bool)

71+import Squeal.PostgreSQL.PG

72+import Squeal.PostgreSQL.Render

73+import Squeal.PostgreSQL.Schema

74+

75+-- $setup

76+-- >>> import Squeal.PostgreSQL

77+

78+-- | Construct a `range`

79+--

80+-- >>> printSQL $ range tstzrange (atLeast now)

81+-- tstzrange(now(), NULL, '[)')

82+-- >>> printSQL $ range numrange (0 <=..< 2*pi)

83+-- numrange(0, (2 * pi()), '[)')

84+-- >>> printSQL $ range int4range Empty

85+-- ('empty' :: int4range)

86+range

87+ :: TypeExpression schemas (null ('PGrange ty))

88+ -> Range (Expression outer commons grp schemas params from ('NotNull ty))

89+ -> Expression outer commons grp schemas params from (null ('PGrange ty))

90+range ty = \case

91+ Empty -> UnsafeExpression $ parenthesized

92+ (emp <+> "::" <+> renderSQL ty)

93+ NonEmpty l u -> UnsafeExpression $ renderSQL ty <> parenthesized

94+ (commaSeparated (args l u))

95+ where

96+ emp = singleQuote <> "empty" <> singleQuote

97+ args l u = [arg l, arg u, singleQuote <> bra l <> ket u <> singleQuote]

98+ singleQuote = "\'"

99+ arg = \case

100+ Infinite -> "NULL"; Closed x -> renderSQL x; Open x -> renderSQL x

101+ bra = \case Infinite -> "("; Closed _ -> "["; Open _ -> "("

102+ ket = \case Infinite -> ")"; Closed _ -> "]"; Open _ -> ")"

103+

104+data Bound x = Infinite | Closed x | Open x

105+ deriving

106+ ( Eq, Ord, Show, Read, GHC.Generic

107+ , Functor, Foldable, Traversable )

108+

109+data Range x = Empty | NonEmpty (Bound x) (Bound x)

110+ deriving

111+ ( Eq, Ord, Show, Read, GHC.Generic

112+ , Functor, Foldable, Traversable )

113+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

114+type instance PG (Range x) = 'PGrange (PG x)

115+instance ToParam x pg => ToParam (Range x) ('PGrange pg) where

116+ toParam rng = K $

117+ word8 (setFlags rng 0) <>

118+ case rng of

119+ Empty -> mempty

120+ NonEmpty lower upper -> putBound lower <> putBound upper

121+ where

122+ putBound = \case

123+ Infinite -> mempty

124+ Closed value -> putValue (unK (toParam @x @pg value))

125+ Open value -> putValue (unK (toParam @x @pg value))

126+ putValue value = int32BE (fromIntegral (builderLength value)) <> value

127+ setFlags = \case

128+ Empty -> (`setBit` 0)

129+ NonEmpty lower upper ->

130+ setLowerFlags lower . setUpperFlags upper

131+ setLowerFlags = \case

132+ Infinite -> (`setBit` 3)

133+ Closed _ -> (`setBit` 1)

134+ Open _ -> id

135+ setUpperFlags = \case

136+ Infinite -> (`setBit` 4)

137+ Closed _ -> (`setBit` 2)

138+ Open _ -> id

139+instance FromValue pg y => FromValue ('PGrange pg) (Range y) where

140+ fromValue = do

141+ flag <- byte

142+ if testBit flag 0 then return Empty else do

143+ lower <-

144+ if testBit flag 3

145+ then return Infinite

146+ else do

147+ len <- sized 4 Decoding.int

148+ l <- sized len (fromValue @pg)

149+ return $ if testBit flag 1 then Closed l else Open l

150+ upper <-

151+ if testBit flag 4

152+ then return Infinite

153+ else do

154+ len <- sized 4 Decoding.int

155+ l <- sized len (fromValue @pg)

156+ return $ if testBit flag 2 then Closed l else Open l

157+ return $ NonEmpty lower upper

158+

159+(<=..<=), (<..<), (<=..<), (<..<=) :: x -> x -> Range x

160+infix 4 <=..<=, <..<, <=..<, <..<=

161+x <=..<= y = NonEmpty (Closed x) (Closed y)

162+x <..< y = NonEmpty (Open x) (Open y)

163+x <=..< y = NonEmpty (Closed x) (Open y)

164+x <..<= y = NonEmpty (Open x) (Closed y)

165+

166+moreThan, atLeast, lessThan, atMost :: x -> Range x

167+moreThan x = NonEmpty (Open x) Infinite

168+atLeast x = NonEmpty (Closed x) Infinite

169+lessThan x = NonEmpty Infinite (Open x)

170+atMost x = NonEmpty Infinite (Closed x)

171+

172+singleton :: x -> Range x

173+singleton x = x <=..<= x

174+

175+whole :: Range x

176+whole = NonEmpty Infinite Infinite

177+

178+(.<@) :: Operator ('NotNull ty) (null ('PGrange ty)) ('Null 'PGbool)

179+(.<@) = unsafeBinaryOp "<@"

180+

181+(@>.) :: Operator (null ('PGrange ty)) ('NotNull ty) ('Null 'PGbool)

182+(@>.) = unsafeBinaryOp "<@"

183+

184+(<<@) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

185+(<<@) = unsafeBinaryOp "<<"

186+

187+(@>>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

188+(@>>) = unsafeBinaryOp ">>"

189+

190+(&<) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

191+(&<) = unsafeBinaryOp "&<"

192+

193+(&>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

194+(&>) = unsafeBinaryOp "&>"

195+

196+(-|-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

197+(-|-) = unsafeBinaryOp "-|-"

198+

199+(@+) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

200+(@+) = unsafeBinaryOp "+"

201+

202+(@*) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

203+(@*) = unsafeBinaryOp "*"

204+

205+(@-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

206+(@-) = unsafeBinaryOp "-"

207+

208+lowerBound :: null ('PGrange ty) --> 'Null ty

209+lowerBound = unsafeFunction "lower"

210+

211+upperBound :: null ('PGrange ty) --> 'Null ty

212+upperBound = unsafeFunction "upper"

213+

214+isEmpty :: null ('PGrange ty) --> 'Null 'PGbool

215+isEmpty = unsafeFunction "isempty"

216+

217+lowerInc :: null ('PGrange ty) --> 'Null 'PGbool

218+lowerInc = unsafeFunction "lower_inc"

219+

220+lowerInf :: null ('PGrange ty) --> 'Null 'PGbool

221+lowerInf = unsafeFunction "lower_inf"

222+

223+upperInc :: null ('PGrange ty) --> 'Null 'PGbool

224+upperInc = unsafeFunction "upper_inc"

225+

226+upperInf :: null ('PGrange ty) --> 'Null 'PGbool

227+upperInf = unsafeFunction "upper_inf"

228+

229+rangeMerge :: '[null ('PGrange ty), null ('PGrange ty)] ---> null ('PGrange ty)

230+rangeMerge = unsafeFunctionN "range_merge"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Set.hsnew file+139

@@ -0,0 +1,139 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Set

3+Description: Set returning functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Set returning functions

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DataKinds

14+ , FlexibleContexts

15+ , OverloadedStrings

16+ , PolyKinds

17+ , RankNTypes

18+ , ScopedTypeVariables

19+ , TypeApplications

20+ , TypeOperators

21+#-}

22+

23+module Squeal.PostgreSQL.Expression.Set

24+ ( generateSeries

25+ , generateSeriesStep

26+ , generateSeriesTimestamp

27+ , SetFunction

28+ , unsafeSetFunction

29+ , SetFunctionDB

30+ , setFunction

31+ , SetFunctionN

32+ , unsafeSetFunctionN

33+ , SetFunctionNDB

34+ , setFunctionN

35+ ) where

36+

37+import GHC.TypeLits

38+

39+import qualified Generics.SOP as SOP

40+

41+import Squeal.PostgreSQL.Alias

42+import Squeal.PostgreSQL.Expression

43+import Squeal.PostgreSQL.List

44+import Squeal.PostgreSQL.Render

45+import Squeal.PostgreSQL.Query

46+import Squeal.PostgreSQL.Schema

47+

48+{- |

49+A @RankNType@ for set returning functions with 1 argument.

50+-}

51+type SetFunction fun ty row

52+ = forall outer commons schemas params

53+ . Expression outer commons 'Ungrouped schemas params '[] ty

54+ -- ^ input

55+ -> FromClause outer commons schemas params '[fun ::: row]

56+ -- ^ output

57+

58+type SetFunctionDB fun schemas ty row

59+ = forall outer commons params

60+ . Expression outer commons 'Ungrouped schemas params '[] ty

61+ -- ^ input

62+ -> FromClause outer commons schemas params '[fun ::: row]

63+ -- ^ output

64+

65+-- | Escape hatch for a set returning function with 1 argument.

66+unsafeSetFunction

67+ :: forall fun ty row. KnownSymbol fun

68+ => SetFunction fun ty row -- ^ set returning function

69+unsafeSetFunction x = UnsafeFromClause $

70+ renderSymbol @fun <> parenthesized (renderSQL x)

71+

72+setFunction

73+ :: ( Has sch schemas schema

74+ , Has fun schema ('Function ('[ty] :=> 'ReturnsTable row)) )

75+ => QualifiedAlias sch fun

76+ -> SetFunctionDB fun schemas ty row

77+setFunction _ = unsafeSetFunction

78+

79+{- |

80+A @RankNType@ for set returning functions with multiple argument.

81+-}

82+type SetFunctionN fun tys row

83+ = forall outer commons schemas params

84+ . NP (Expression outer commons 'Ungrouped schemas params '[]) tys

85+ -- ^ inputs

86+ -> FromClause outer commons schemas params '[fun ::: row]

87+ -- ^ output

88+

89+-- | Escape hatch for a set returning function with multiple argument.

90+unsafeSetFunctionN

91+ :: forall fun tys row. (SOP.SListI tys, KnownSymbol fun)

92+ => SetFunctionN fun tys row -- ^ set returning function

93+unsafeSetFunctionN xs = UnsafeFromClause $

94+ renderSymbol @fun <> parenthesized (renderCommaSeparated renderSQL xs)

95+

96+type SetFunctionNDB fun schemas tys row

97+ = forall outer commons params

98+ . NP (Expression outer commons 'Ungrouped schemas params '[]) tys

99+ -- ^ inputs

100+ -> FromClause outer commons schemas params '[fun ::: row]

101+ -- ^ output

102+

103+setFunctionN

104+ :: ( Has sch schemas schema

105+ , Has fun schema ('Function (tys :=> 'ReturnsTable row))

106+ , SOP.SListI tys )

107+ => QualifiedAlias sch fun

108+ -> SetFunctionNDB fun schemas tys row

109+setFunctionN _ = unsafeSetFunctionN

110+

111+{- | @generateSeries (start *: stop)@

112+

113+Generate a series of values, from @start@ to @stop@ with a step size of one

114+-}

115+generateSeries

116+ :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

117+ => SetFunctionN "generate_series" '[ null ty, null ty]

118+ '["generate_series" ::: null ty] -- ^ set returning function

119+generateSeries = unsafeSetFunctionN

120+

121+{- | @generateSeries (start :* stop *: step)@

122+

123+Generate a series of values, from @start@ to @stop@ with a step size of @step@

124+-}

125+generateSeriesStep

126+ :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

127+ => SetFunctionN "generate_series" '[null ty, null ty, null ty]

128+ '["generate_series" ::: null ty] -- ^ set returning function

129+generateSeriesStep = unsafeSetFunctionN

130+

131+{- | @generateSeries (start :* stop *: step)@

132+

133+Generate a series of values, from @start@ to @stop@ with a step size of @step@

134+-}

135+generateSeriesTimestamp

136+ :: ty `In` '[ 'PGtimestamp, 'PGtimestamptz]

137+ => SetFunctionN "generate_series" '[null ty, null ty, null 'PGinterval]

138+ '["generate_series" ::: null ty] -- ^ set returning function

139+generateSeriesTimestamp = unsafeSetFunctionN

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Sort.hsnew file+85

@@ -0,0 +1,85 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Sort

3+Description: Sort expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

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+157

@@ -0,0 +1,157 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.TextSearch

3+Description: Text search expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Text search functions and operators

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , OverloadedStrings

14+ , TypeOperators

15+#-}

16+

17+module Squeal.PostgreSQL.Expression.TextSearch

18+ ( (@@)

19+ , (.&)

20+ , (.|)

21+ , (.!)

22+ , (<->)

23+ , arrayToTSvector

24+ , tsvectorLength

25+ , numnode

26+ , plainToTSquery

27+ , phraseToTSquery

28+ , websearchToTSquery

29+ , queryTree

30+ , toTSquery

31+ , toTSvector

32+ , setWeight

33+ , strip

34+ , jsonToTSvector

35+ , jsonbToTSvector

36+ , tsDelete

37+ , tsFilter

38+ , tsHeadline

39+ ) where

40+

41+import Squeal.PostgreSQL.Expression

42+import Squeal.PostgreSQL.List

43+import Squeal.PostgreSQL.Schema

44+

45+-- | `Squeal.PostgreSQL.Expression.Type.tsvector` matches tsquery ?

46+(@@) :: Operator (null 'PGtsvector) (null 'PGtsquery) ('Null 'PGbool)

47+(@@) = unsafeBinaryOp "@@"

48+

49+-- | AND `Squeal.PostgreSQL.Expression.Type.tsquery`s together

50+(.&) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

51+(.&) = unsafeBinaryOp "&&"

52+

53+-- | OR `Squeal.PostgreSQL.Expression.Type.tsquery`s together

54+(.|) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

55+(.|) = unsafeBinaryOp "||"

56+

57+-- | negate a `Squeal.PostgreSQL.Expression.Type.tsquery`

58+(.!) :: null 'PGtsquery --> null 'PGtsquery

59+(.!) = unsafeLeftOp "!!"

60+

61+-- | `Squeal.PostgreSQL.Expression.Type.tsquery` followed by

62+-- `Squeal.PostgreSQL.Expression.Type.tsquery`

63+(<->) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

64+(<->) = unsafeBinaryOp "<->"

65+

66+-- | convert array of lexemes to `Squeal.PostgreSQL.Expression.Type.tsvector`

67+arrayToTSvector

68+ :: null ('PGvararray ('NotNull 'PGtext))

69+ --> null 'PGtsvector

70+arrayToTSvector = unsafeFunction "array_to_tsvector"

71+

72+-- | number of lexemes in `Squeal.PostgreSQL.Expression.Type.tsvector`

73+tsvectorLength :: null 'PGtsvector --> null 'PGint4

74+tsvectorLength = unsafeFunction "length"

75+

76+-- | number of lexemes plus operators in `Squeal.PostgreSQL.Expression.Type.tsquery`

77+numnode :: null 'PGtsquery --> null 'PGint4

78+numnode = unsafeFunction "numnode"

79+

80+-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` ignoring punctuation

81+plainToTSquery :: null 'PGtext --> null 'PGtsquery

82+plainToTSquery = unsafeFunction "plainto_tsquery"

83+

84+-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` that searches for a phrase,

85+-- ignoring punctuation

86+phraseToTSquery :: null 'PGtext --> null 'PGtsquery

87+phraseToTSquery = unsafeFunction "phraseto_tsquery"

88+

89+-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` from a web search style query

90+websearchToTSquery :: null 'PGtext --> null 'PGtsquery

91+websearchToTSquery = unsafeFunction "websearch_to_tsquery"

92+

93+-- | get indexable part of a `Squeal.PostgreSQL.Expression.Type.tsquery`

94+queryTree :: null 'PGtsquery --> null 'PGtext

95+queryTree = unsafeFunction "query_tree"

96+

97+-- | normalize words and convert to `Squeal.PostgreSQL.Expression.Type.tsquery`

98+toTSquery :: null 'PGtext --> null 'PGtsquery

99+toTSquery = unsafeFunction "to_tsquery"

100+

101+-- | reduce document text to `Squeal.PostgreSQL.Expression.Type.tsvector`

102+toTSvector

103+ :: ty `In` '[ 'PGtext, 'PGjson, 'PGjsonb]

104+ => null ty --> null 'PGtsvector

105+toTSvector = unsafeFunction "to_tsvector"

106+

107+-- | assign weight to each element of `Squeal.PostgreSQL.Expression.Type.tsvector`

108+setWeight :: '[null 'PGtsvector, null ('PGchar 1)] ---> null 'PGtsvector

109+setWeight = unsafeFunctionN "set_weight"

110+

111+-- | remove positions and weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

112+strip :: null 'PGtsvector --> null 'PGtsvector

113+strip = unsafeFunction "strip"

114+

115+-- | @jsonToTSvector (document *: filter)@

116+-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

117+-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

118+-- filter is a `Squeal.PostgreSQL.Expression.Type.json` array, that enumerates what kind of elements

119+-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

120+-- Possible values for filter are "string" (to include all string values),

121+-- "numeric" (to include all numeric values in the string format),

122+-- "boolean" (to include all Boolean values in the string format "true"/"false"),

123+-- "key" (to include all keys) or "all" (to include all above).

124+-- These values can be combined together to include, e.g. all string and numeric values.

125+jsonToTSvector :: '[null 'PGjson, null 'PGjson] ---> null 'PGtsvector

126+jsonToTSvector = unsafeFunctionN "json_to_tsvector"

127+

128+-- | @jsonbToTSvector (document *: filter)@

129+-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

130+-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

131+-- filter is a `Squeal.PostgreSQL.Expression.Type.jsonb` array, that enumerates what kind of elements

132+-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

133+-- Possible values for filter are "string" (to include all string values),

134+-- "numeric" (to include all numeric values in the string format),

135+-- "boolean" (to include all Boolean values in the string format "true"/"false"),

136+-- "key" (to include all keys) or "all" (to include all above).

137+-- These values can be combined together to include, e.g. all string and numeric values.

138+jsonbToTSvector :: '[null 'PGjsonb, null 'PGjsonb] ---> null 'PGtsvector

139+jsonbToTSvector = unsafeFunctionN "jsonb_to_tsvector"

140+

141+-- | remove given lexeme from `Squeal.PostgreSQL.Expression.Type.tsvector`

142+tsDelete ::

143+ '[null 'PGtsvector, null ('PGvararray ('NotNull 'PGtext))]

144+ ---> null 'PGtsvector

145+tsDelete = unsafeFunctionN "ts_delete"

146+

147+-- | select only elements with given weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

148+tsFilter ::

149+ '[null 'PGtsvector, null ('PGvararray ('NotNull ('PGchar 1)))]

150+ ---> null 'PGtsvector

151+tsFilter = unsafeFunctionN "ts_filter"

152+

153+-- | display a `Squeal.PostgreSQL.Expression.Type.tsquery` match

154+tsHeadline

155+ :: document `In` '[ 'PGtext, 'PGjson, 'PGjsonb]

156+ => '[null document, null 'PGtsquery] ---> null 'PGtext

157+tsHeadline = unsafeFunctionN "ts_headline"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Time.hsnew file+192

@@ -0,0 +1,192 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Time

3+Description: Date/Time expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Date/Time functions and operators

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , DeriveGeneric

14+ , FunctionalDependencies

15+ , LambdaCase

16+ , MultiParamTypeClasses

17+ , OverloadedStrings

18+ , PolyKinds

19+ , RankNTypes

20+ , TypeOperators

21+#-}

22+

23+module Squeal.PostgreSQL.Expression.Time

24+ ( TimeOp (..)

25+ , currentDate

26+ , currentTime

27+ , currentTimestamp

28+ , localTime

29+ , localTimestamp

30+ , now

31+ , makeDate

32+ , makeTime

33+ , makeTimestamp

34+ , makeTimestamptz

35+ , interval_

36+ , TimeUnit (..)

37+ ) where

38+

39+import Data.String

40+

41+import qualified GHC.Generics as GHC

42+import qualified Generics.SOP as SOP

43+

44+import Squeal.PostgreSQL.Expression

45+import Squeal.PostgreSQL.Render

46+import Squeal.PostgreSQL.Schema

47+

48+-- $setup

49+-- >>> import Squeal.PostgreSQL

50+

51+-- | >>> printSQL currentDate

52+-- CURRENT_DATE

53+currentDate :: Expr (null 'PGdate)

54+currentDate = UnsafeExpression "CURRENT_DATE"

55+

56+-- | >>> printSQL currentTime

57+-- CURRENT_TIME

58+currentTime :: Expr (null 'PGtimetz)

59+currentTime = UnsafeExpression "CURRENT_TIME"

60+

61+-- | >>> printSQL currentTimestamp

62+-- CURRENT_TIMESTAMP

63+currentTimestamp :: Expr (null 'PGtimestamptz)

64+currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

65+

66+-- | >>> printSQL localTime

67+-- LOCALTIME

68+localTime :: Expr (null 'PGtime)

69+localTime = UnsafeExpression "LOCALTIME"

70+

71+-- | >>> printSQL localTimestamp

72+-- LOCALTIMESTAMP

73+localTimestamp :: Expr (null 'PGtimestamp)

74+localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

75+

76+-- | Current date and time (equivalent to `currentTimestamp`)

77+--

78+-- >>> printSQL now

79+-- now()

80+now :: Expr (null 'PGtimestamptz)

81+now = UnsafeExpression "now()"

82+

83+{-|

84+Create date from year, month and day fields

85+

86+>>> printSQL (makeDate (1984 :* 7 *: 3))

87+make_date(1984, 7, 3)

88+-}

89+makeDate :: '[ null 'PGint4, null 'PGint4, null 'PGint4 ] ---> null 'PGdate

90+makeDate = unsafeFunctionN "make_date"

91+

92+{-|

93+Create time from hour, minute and seconds fields

94+

95+>>> printSQL (makeTime (8 :* 15 *: 23.5))

96+make_time(8, 15, 23.5)

97+-}

98+makeTime :: '[ null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtime

99+makeTime = unsafeFunctionN "make_time"

100+

101+{-|

102+Create timestamp from year, month, day, hour, minute and seconds fields

103+

104+>>> printSQL (makeTimestamp (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

105+make_timestamp(2013, 7, 15, 8, 15, 23.5)

106+-}

107+makeTimestamp ::

108+ '[ null 'PGint4, null 'PGint4, null 'PGint4

109+ , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamp

110+makeTimestamp = unsafeFunctionN "make_timestamp"

111+

112+{-|

113+Create timestamp with time zone from

114+year, month, day, hour, minute and seconds fields;

115+the current time zone is used

116+

117+>>> printSQL (makeTimestamptz (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

118+make_timestamptz(2013, 7, 15, 8, 15, 23.5)

119+-}

120+makeTimestamptz ::

121+ '[ null 'PGint4, null 'PGint4, null 'PGint4

122+ , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamptz

123+makeTimestamptz = unsafeFunctionN "make_timestamptz"

124+

125+{-|

126+Affine space operations on time types.

127+-}

128+class TimeOp time diff | time -> diff where

129+ {-|

130+ >>> printSQL (makeDate (1984 :* 7 *: 3) !+ 365)

131+ (make_date(1984, 7, 3) + 365)

132+ -}

133+ (!+) :: Operator (null time) (null diff) (null time)

134+ (!+) = unsafeBinaryOp "+"

135+ {-|

136+ >>> printSQL (365 +! makeDate (1984 :* 7 *: 3))

137+ (365 + make_date(1984, 7, 3))

138+ -}

139+ (+!) :: Operator (null diff) (null time) (null time)

140+ (+!) = unsafeBinaryOp "+"

141+ {-|

142+ >>> printSQL (makeDate (1984 :* 7 *: 3) !- 365)

143+ (make_date(1984, 7, 3) - 365)

144+ -}

145+ (!-) :: Operator (null time) (null diff) (null time)

146+ (!-) = unsafeBinaryOp "-"

147+ {-|

148+ >>> printSQL (makeDate (1984 :* 7 *: 3) !-! currentDate)

149+ (make_date(1984, 7, 3) - CURRENT_DATE)

150+ -}

151+ (!-!) :: Operator (null time) (null time) (null diff)

152+ (!-!) = unsafeBinaryOp "-"

153+instance TimeOp 'PGtimestamp 'PGinterval

154+instance TimeOp 'PGtimestamptz 'PGinterval

155+instance TimeOp 'PGtime 'PGinterval

156+instance TimeOp 'PGtimetz 'PGinterval

157+instance TimeOp 'PGinterval 'PGinterval

158+instance TimeOp 'PGdate 'PGint4

159+infixl 6 !+

160+infixl 6 +!

161+infixl 6 !-

162+infixl 6 !-!

163+

164+-- | A `TimeUnit` to use in `interval_` construction.

165+data TimeUnit

166+ = Years | Months | Weeks | Days

167+ | Hours | Minutes | Seconds

168+ | Microseconds | Milliseconds

169+ | Decades | Centuries | Millennia

170+ deriving (Eq, Ord, Show, Read, Enum, GHC.Generic)

171+instance SOP.Generic TimeUnit

172+instance SOP.HasDatatypeInfo TimeUnit

173+instance RenderSQL TimeUnit where

174+ renderSQL = \case

175+ Years -> "years"

176+ Months -> "months"

177+ Weeks -> "weeks"

178+ Days -> "days"

179+ Hours -> "hours"

180+ Minutes -> "minutes"

181+ Seconds -> "seconds"

182+ Microseconds -> "microseconds"

183+ Milliseconds -> "milliseconds"

184+ Decades -> "decades"

185+ Centuries -> "centuries"

186+ Millennia -> "millennia"

187+

188+-- | >>> printSQL $ interval_ 7 Days

189+-- (INTERVAL '7.0 days')

190+interval_ :: Double -> TimeUnit -> Expr (null 'PGinterval)

191+interval_ num unit = UnsafeExpression . parenthesized $ "INTERVAL" <+>

192+ "'" <> fromString (show num) <+> renderSQL unit <> "'"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Type.hsnew file+446

@@ -0,0 +1,446 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression

3+Description: Type expressions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Type expressions.

9+-}

10+

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DataKinds

14+ , DeriveGeneric

15+ , FlexibleContexts

16+ , FlexibleInstances

17+ , GADTs

18+ , GeneralizedNewtypeDeriving

19+ , KindSignatures

20+ , MultiParamTypeClasses

21+ , OverloadedStrings

22+ , RankNTypes

23+ , ScopedTypeVariables

24+ , TypeApplications

25+ , TypeOperators

26+ , UndecidableInstances

27+#-}

28+

29+module Squeal.PostgreSQL.Expression.Type

30+ ( -- * type casting

31+ cast

32+ , astype

33+ , inferredtype

34+ -- * type expressions

35+ , TypeExpression (..)

36+ , typedef

37+ , typetable

38+ , typeview

39+ , bool

40+ , int2

41+ , smallint

42+ , int4

43+ , int

44+ , integer

45+ , int8

46+ , bigint

47+ , numeric

48+ , float4

49+ , real

50+ , float8

51+ , doublePrecision

52+ , money

53+ , text

54+ , char

55+ , character

56+ , varchar

57+ , characterVarying

58+ , bytea

59+ , timestamp

60+ , timestampWithTimeZone

61+ , timestamptz

62+ , date

63+ , time

64+ , timeWithTimeZone

65+ , timetz

66+ , interval

67+ , uuid

68+ , inet

69+ , json

70+ , jsonb

71+ , vararray

72+ , fixarray

73+ , tsvector

74+ , tsquery

75+ , oid

76+ , int4range

77+ , int8range

78+ , numrange

79+ , tsrange

80+ , tstzrange

81+ , daterange

82+ -- * column type definitions

83+ , ColumnTypeExpression (..)

84+ , nullable

85+ , notNullable

86+ , default_

87+ , serial2

88+ , smallserial

89+ , serial4

90+ , serial

91+ , serial8

92+ , bigserial

93+ , hask

94+ -- * type inference

95+ , PGTyped (..)

96+ , PGNullityTyped (..)

97+ , FieldTyped (..)

98+ ) where

99+

100+import Control.DeepSeq

101+import Data.ByteString

102+import Data.String

103+import GHC.TypeLits

104+

105+import qualified Data.ByteString as ByteString

106+import qualified GHC.Generics as GHC

107+import qualified Generics.SOP as SOP

108+

109+import Squeal.PostgreSQL.Alias

110+import Squeal.PostgreSQL.Expression

111+import Squeal.PostgreSQL.PG

112+import Squeal.PostgreSQL.Render

113+import Squeal.PostgreSQL.Schema

114+

115+-- $setup

116+-- >>> import Squeal.PostgreSQL

117+

118+-- When a `cast` is applied to an `Expression` of a known type, it

119+-- represents a run-time type conversion. The cast will succeed only if a

120+-- suitable type conversion operation has been defined.

121+--

122+-- | >>> printSQL $ true & cast int4

123+-- (TRUE :: int4)

124+cast

125+ :: TypeExpression schemas ty1

126+ -- ^ type to cast as

127+ -> Expression outer commons grp schemas params from ty0

128+ -- ^ value to convert

129+ -> Expression outer commons grp schemas params from ty1

130+cast ty x = UnsafeExpression $ parenthesized $

131+ renderSQL x <+> "::" <+> renderSQL ty

132+

133+-- | A safe version of `cast` which just matches a value with its type.

134+--

135+-- >>> printSQL (1 & astype int)

136+-- (1 :: int)

137+astype

138+ :: TypeExpression schemas ty

139+ -- ^ type to specify as

140+ -> Expression outer commons grp schemas params from ty

141+ -- ^ value

142+ -> Expression outer commons grp schemas params from ty

143+astype = cast

144+

145+-- | `inferredtype` will add a type annotation to an `Expression`

146+-- which can be useful for fixing the storage type of a value.

147+--

148+-- >>> printSQL (inferredtype true)

149+-- (TRUE :: bool)

150+inferredtype

151+ :: PGTyped schemas ty

152+ => Expression outer common grp schemas params from ty

153+ -- ^ value

154+ -> Expression outer common grp schemas params from ty

155+inferredtype = astype pgtype

156+

157+{-----------------------------------------

158+type expressions

159+-----------------------------------------}

160+

161+-- | `TypeExpression`s are used in `cast`s and

162+-- `Squeal.PostgreSQL.Definition.createTable` commands.

163+newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)

164+ = UnsafeTypeExpression { renderTypeExpression :: ByteString }

165+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

166+instance RenderSQL (TypeExpression schemas ty) where

167+ renderSQL = renderTypeExpression

168+

169+-- | The enum or composite type in a `Typedef` can be expressed by its alias.

170+typedef

171+ :: (Has sch schemas schema, Has td schema ('Typedef ty))

172+ => QualifiedAlias sch td

173+ -- ^ type alias

174+ -> TypeExpression schemas (null ty)

175+typedef = UnsafeTypeExpression . renderSQL

176+

177+-- | The composite type corresponding to a `Table` definition can be expressed

178+-- by its alias.

179+typetable

180+ :: (Has sch schemas schema, Has tab schema ('Table table))

181+ => QualifiedAlias sch tab

182+ -- ^ table alias

183+ -> TypeExpression schemas (null ('PGcomposite (TableToRow table)))

184+typetable = UnsafeTypeExpression . renderSQL

185+

186+-- | The composite type corresponding to a `View` definition can be expressed

187+-- by its alias.

188+typeview

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

190+ => QualifiedAlias sch vw

191+ -- ^ view alias

192+ -> TypeExpression schemas (null ('PGcomposite view))

193+typeview = UnsafeTypeExpression . renderSQL

194+

195+-- | logical Boolean (true/false)

196+bool :: TypeExpression schemas (null 'PGbool)

197+bool = UnsafeTypeExpression "bool"

198+-- | signed two-byte integer

199+int2, smallint :: TypeExpression schemas (null 'PGint2)

200+int2 = UnsafeTypeExpression "int2"

201+smallint = UnsafeTypeExpression "smallint"

202+-- | signed four-byte integer

203+int4, int, integer :: TypeExpression schemas (null 'PGint4)

204+int4 = UnsafeTypeExpression "int4"

205+int = UnsafeTypeExpression "int"

206+integer = UnsafeTypeExpression "integer"

207+-- | signed eight-byte integer

208+int8, bigint :: TypeExpression schemas (null 'PGint8)

209+int8 = UnsafeTypeExpression "int8"

210+bigint = UnsafeTypeExpression "bigint"

211+-- | arbitrary precision numeric type

212+numeric :: TypeExpression schemas (null 'PGnumeric)

213+numeric = UnsafeTypeExpression "numeric"

214+-- | single precision floating-point number (4 bytes)

215+float4, real :: TypeExpression schemas (null 'PGfloat4)

216+float4 = UnsafeTypeExpression "float4"

217+real = UnsafeTypeExpression "real"

218+-- | double precision floating-point number (8 bytes)

219+float8, doublePrecision :: TypeExpression schemas (null 'PGfloat8)

220+float8 = UnsafeTypeExpression "float8"

221+doublePrecision = UnsafeTypeExpression "double precision"

222+-- | currency amount

223+money :: TypeExpression schema (null 'PGmoney)

224+money = UnsafeTypeExpression "money"

225+-- | variable-length character string

226+text :: TypeExpression schemas (null 'PGtext)

227+text = UnsafeTypeExpression "text"

228+-- | fixed-length character string

229+char, character

230+ :: forall n schemas null. (KnownNat n, 1 <= n)

231+ => TypeExpression schemas (null ('PGchar n))

232+char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"

233+character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"

234+-- | variable-length character string

235+varchar, characterVarying

236+ :: forall n schemas null. (KnownNat n, 1 <= n)

237+ => TypeExpression schemas (null ('PGvarchar n))

238+varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"

239+characterVarying = UnsafeTypeExpression $

240+ "character varying(" <> renderNat @n <> ")"

241+-- | binary data ("byte array")

242+bytea :: TypeExpression schemas (null 'PGbytea)

243+bytea = UnsafeTypeExpression "bytea"

244+-- | date and time (no time zone)

245+timestamp :: TypeExpression schemas (null 'PGtimestamp)

246+timestamp = UnsafeTypeExpression "timestamp"

247+-- | date and time, including time zone

248+timestampWithTimeZone, timestamptz :: TypeExpression schemas (null 'PGtimestamptz)

249+timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

250+timestamptz = UnsafeTypeExpression "timestamptz"

251+-- | calendar date (year, month, day)

252+date :: TypeExpression schemas (null 'PGdate)

253+date = UnsafeTypeExpression "date"

254+-- | time of day (no time zone)

255+time :: TypeExpression schemas (null 'PGtime)

256+time = UnsafeTypeExpression "time"

257+-- | time of day, including time zone

258+timeWithTimeZone, timetz :: TypeExpression schemas (null 'PGtimetz)

259+timeWithTimeZone = UnsafeTypeExpression "time with time zone"

260+timetz = UnsafeTypeExpression "timetz"

261+-- | time span

262+interval :: TypeExpression schemas (null 'PGinterval)

263+interval = UnsafeTypeExpression "interval"

264+-- | universally unique identifier

265+uuid :: TypeExpression schemas (null 'PGuuid)

266+uuid = UnsafeTypeExpression "uuid"

267+-- | IPv4 or IPv6 host address

268+inet :: TypeExpression schemas (null 'PGinet)

269+inet = UnsafeTypeExpression "inet"

270+-- | textual JSON data

271+json :: TypeExpression schemas (null 'PGjson)

272+json = UnsafeTypeExpression "json"

273+-- | binary JSON data, decomposed

274+jsonb :: TypeExpression schemas (null 'PGjsonb)

275+jsonb = UnsafeTypeExpression "jsonb"

276+-- | variable length array

277+vararray

278+ :: TypeExpression schemas pg

279+ -> TypeExpression schemas (null ('PGvararray pg))

280+vararray ty = UnsafeTypeExpression $ renderSQL ty <> "[]"

281+-- | fixed length array

282+--

283+-- >>> renderSQL (fixarray @'[2] json)

284+-- "json[2]"

285+fixarray

286+ :: forall dims schemas null pg. SOP.All KnownNat dims

287+ => TypeExpression schemas pg

288+ -> TypeExpression schemas (null ('PGfixarray dims pg))

289+fixarray ty = UnsafeTypeExpression $

290+ renderSQL ty <> renderDims @dims

291+ where

292+ renderDims :: forall ns. SOP.All KnownNat ns => ByteString

293+ renderDims =

294+ ("[" <>)

295+ . (<> "]")

296+ . ByteString.intercalate "]["

297+ . SOP.hcollapse

298+ $ SOP.hcmap (SOP.Proxy @KnownNat)

299+ (K . fromString . show . natVal)

300+ (SOP.hpure SOP.Proxy :: SOP.NP SOP.Proxy ns)

301+-- | text search query

302+tsvector :: TypeExpression schemas (null 'PGtsvector)

303+tsvector = UnsafeTypeExpression "tsvector"

304+-- | text search document

305+tsquery :: TypeExpression schemas (null 'PGtsquery)

306+tsquery = UnsafeTypeExpression "tsquery"

307+-- | Object identifiers (OIDs) are used internally by PostgreSQL

308+-- as primary keys for various system tables.

309+oid :: TypeExpression schemas (null 'PGoid)

310+oid = UnsafeTypeExpression "oid"

311+-- | Range of integer

312+int4range :: TypeExpression schemas (null ('PGrange 'PGint4))

313+int4range = UnsafeTypeExpression "int4range"

314+-- | Range of bigint

315+int8range :: TypeExpression schemas (null ('PGrange 'PGint8))

316+int8range = UnsafeTypeExpression "int8range"

317+-- | Range of numeric

318+numrange :: TypeExpression schemas (null ('PGrange 'PGnumeric))

319+numrange = UnsafeTypeExpression "numrange"

320+-- | Range of timestamp without time zone

321+tsrange :: TypeExpression schemas (null ('PGrange 'PGtimestamp))

322+tsrange = UnsafeTypeExpression "tsrange"

323+-- | Range of timestamp with time zone

324+tstzrange :: TypeExpression schemas (null ('PGrange 'PGtimestamptz))

325+tstzrange = UnsafeTypeExpression "tstzrange"

326+-- | Range of date

327+daterange :: TypeExpression schemas (null ('PGrange 'PGdate))

328+daterange = UnsafeTypeExpression "daterange"

329+

330+-- | `pgtype` is a demoted version of a `PGType`

331+class PGTyped schemas (ty :: NullityType) where

332+ pgtype :: TypeExpression schemas ty

333+instance PGTyped schemas (null 'PGbool) where pgtype = bool

334+instance PGTyped schemas (null 'PGint2) where pgtype = int2

335+instance PGTyped schemas (null 'PGint4) where pgtype = int4

336+instance PGTyped schemas (null 'PGint8) where pgtype = int8

337+instance PGTyped schemas (null 'PGnumeric) where pgtype = numeric

338+instance PGTyped schemas (null 'PGfloat4) where pgtype = float4

339+instance PGTyped schemas (null 'PGfloat8) where pgtype = float8

340+instance PGTyped schemas (null 'PGmoney) where pgtype = money

341+instance PGTyped schemas (null 'PGtext) where pgtype = text

342+instance (KnownNat n, 1 <= n)

343+ => PGTyped schemas (null ('PGchar n)) where pgtype = char @n

344+instance (KnownNat n, 1 <= n)

345+ => PGTyped schemas (null ('PGvarchar n)) where pgtype = varchar @n

346+instance PGTyped schemas (null 'PGbytea) where pgtype = bytea

347+instance PGTyped schemas (null 'PGtimestamp) where pgtype = timestamp

348+instance PGTyped schemas (null 'PGtimestamptz) where pgtype = timestampWithTimeZone

349+instance PGTyped schemas (null 'PGdate) where pgtype = date

350+instance PGTyped schemas (null 'PGtime) where pgtype = time

351+instance PGTyped schemas (null 'PGtimetz) where pgtype = timeWithTimeZone

352+instance PGTyped schemas (null 'PGinterval) where pgtype = interval

353+instance PGTyped schemas (null 'PGuuid) where pgtype = uuid

354+instance PGTyped schemas (null 'PGjson) where pgtype = json

355+instance PGTyped schemas (null 'PGjsonb) where pgtype = jsonb

356+instance PGTyped schemas ty

357+ => PGTyped schemas (null ('PGvararray ty)) where

358+ pgtype = vararray (pgtype @schemas @ty)

359+instance (SOP.All KnownNat dims, PGTyped schemas ty)

360+ => PGTyped schemas (null ('PGfixarray dims ty)) where

361+ pgtype = fixarray @dims (pgtype @schemas @ty)

362+instance PGTyped schemas (null 'PGtsvector) where pgtype = tsvector

363+instance PGTyped schemas (null 'PGtsquery) where pgtype = tsquery

364+instance PGTyped schemas (null 'PGoid) where pgtype = oid

365+instance PGTyped schemas (null ('PGrange 'PGint4)) where pgtype = int4range

366+instance PGTyped schemas (null ('PGrange 'PGint8)) where pgtype = int8range

367+instance PGTyped schemas (null ('PGrange 'PGnumeric)) where pgtype = numrange

368+instance PGTyped schemas (null ('PGrange 'PGtimestamp)) where pgtype = tsrange

369+instance PGTyped schemas (null ('PGrange 'PGtimestamptz)) where pgtype = tstzrange

370+instance PGTyped schemas (null ('PGrange 'PGdate)) where pgtype = daterange

371+

372+-- | Lift `PGTyped` to a field

373+class FieldTyped schemas ty where

374+ fieldtype :: Aliased (TypeExpression schemas) ty

375+instance (KnownSymbol alias, PGTyped schemas ty)

376+ => FieldTyped schemas (alias ::: ty) where

377+ fieldtype = pgtype `As` Alias

378+

379+-- | `ColumnTypeExpression`s are used in `createTable` commands.

380+newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)

381+ = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }

382+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

383+instance RenderSQL (ColumnTypeExpression schemas ty) where

384+ renderSQL = renderColumnTypeExpression

385+

386+-- | used in `createTable` commands as a column constraint to note that

387+-- @NULL@ may be present in a column

388+nullable

389+ :: TypeExpression schemas (nullity ty)

390+ -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)

391+nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"

392+

393+-- | used in `createTable` commands as a column constraint to ensure

394+-- @NULL@ is not present in a column

395+notNullable

396+ :: TypeExpression schemas (nullity ty)

397+ -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)

398+notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"

399+

400+-- | used in `createTable` commands as a column constraint to give a default

401+default_

402+ :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty

403+ -> ColumnTypeExpression schemas ('NoDef :=> ty)

404+ -> ColumnTypeExpression schemas ('Def :=> ty)

405+default_ x ty = UnsafeColumnTypeExpression $

406+ renderSQL ty <+> "DEFAULT" <+> renderExpression x

407+

408+-- | not a true type, but merely a notational convenience for creating

409+-- unique identifier columns with type `PGint2`

410+serial2, smallserial

411+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)

412+serial2 = UnsafeColumnTypeExpression "serial2"

413+smallserial = UnsafeColumnTypeExpression "smallserial"

414+-- | not a true type, but merely a notational convenience for creating

415+-- unique identifier columns with type `PGint4`

416+serial4, serial

417+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)

418+serial4 = UnsafeColumnTypeExpression "serial4"

419+serial = UnsafeColumnTypeExpression "serial"

420+-- | not a true type, but merely a notational convenience for creating

421+-- unique identifier columns with type `PGint8`

422+serial8, bigserial

423+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)

424+serial8 = UnsafeColumnTypeExpression "serial8"

425+bigserial = UnsafeColumnTypeExpression "bigserial"

426+

427+-- | Like @PGTyped@ but also accounts for nullity.

428+class PGNullityTyped schemas (nullty :: NullityType) where

429+ pgNullityType :: ColumnTypeExpression schemas ('NoDef :=> nullty)

430+

431+instance PGTyped schemas ('Null ty) => PGNullityTyped schemas ('Null ty) where

432+ pgNullityType = nullable (pgtype @_ @('Null ty))

433+

434+instance PGTyped schemas ('NotNull ty) => PGNullityTyped schemas ('NotNull ty) where

435+ pgNullityType = notNullable (pgtype @_ @('NotNull ty))

436+

437+-- | Allow you to specify pg column types in relation to haskell types.

438+-- >>> printSQL $ hask @(Maybe String)

439+-- text NULL

440+--

441+-- >>> printSQL $ hask @Double

442+-- float8 NOT NULL

443+hask

444+ :: forall hask schemas. PGNullityTyped schemas (NullPG hask)

445+ => ColumnTypeExpression schemas ('NoDef :=> NullPG hask)

446+hask = pgNullityType

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Window.hsnew file+284

@@ -0,0 +1,284 @@

1+{-|

2+Module: Squeal.PostgreSQL.Expression.Window

3+Description: Window functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Window functions and definitions

9+-}

10+

11+{-# LANGUAGE

12+ DataKinds

13+ , DeriveGeneric

14+ , FlexibleContexts

15+ , FlexibleInstances

16+ , GADTs

17+ , GeneralizedNewtypeDeriving

18+ , LambdaCase

19+ , MultiParamTypeClasses

20+ , OverloadedStrings

21+ , RankNTypes

22+ , KindSignatures

23+#-}

24+

25+module Squeal.PostgreSQL.Expression.Window

26+ ( -- * functions

27+ partitionBy

28+ , rank

29+ , rowNumber

30+ , denseRank

31+ , percentRank

32+ , cumeDist

33+ , ntile

34+ , lag

35+ , lead

36+ , firstValue

37+ , lastValue

38+ , nthValue

39+ , unsafeWindowFunction1

40+ , unsafeWindowFunctionN

41+ -- * types

42+ , WindowFunction (..)

43+ , WindowDefinition (..)

44+ , WinFun0

45+ , WinFun1

46+ , WinFunN

47+ ) where

48+

49+import Control.DeepSeq

50+import Data.ByteString

51+

52+import qualified GHC.Generics as GHC

53+import qualified Generics.SOP as SOP

54+

55+import Squeal.PostgreSQL.Alias

56+import Squeal.PostgreSQL.Expression

57+import Squeal.PostgreSQL.Expression.Aggregate

58+import Squeal.PostgreSQL.Expression.Sort

59+import Squeal.PostgreSQL.List

60+import Squeal.PostgreSQL.Render

61+import Squeal.PostgreSQL.Schema

62+

63+instance Aggregate

64+ (Expression outer commons grp schemas params from)

65+ (NP (Expression outer commons grp schemas params from))

66+ (WindowFunction outer commons grp schemas params from) where

67+ countStar = UnsafeWindowFunction "count(*)"

68+ count = unsafeWindowFunction1 "count"

69+ sum_ = unsafeWindowFunction1 "sum"

70+ arrayAgg = unsafeWindowFunction1 "array_agg"

71+ jsonAgg = unsafeWindowFunction1 "json_agg"

72+ jsonbAgg = unsafeWindowFunction1 "jsonb_agg"

73+ bitAnd = unsafeWindowFunction1 "bit_and"

74+ bitOr = unsafeWindowFunction1 "bit_or"

75+ boolAnd = unsafeWindowFunction1 "bool_and"

76+ boolOr = unsafeWindowFunction1 "bool_or"

77+ every = unsafeWindowFunction1 "every"

78+ max_ = unsafeWindowFunction1 "max"

79+ min_ = unsafeWindowFunction1 "min"

80+ avg = unsafeWindowFunction1 "avg"

81+ corr = unsafeWindowFunctionN "corr"

82+ covarPop = unsafeWindowFunctionN "covar_pop"

83+ covarSamp = unsafeWindowFunctionN "covar_samp"

84+ regrAvgX = unsafeWindowFunctionN "regr_avgx"

85+ regrAvgY = unsafeWindowFunctionN "regr_avgy"

86+ regrCount = unsafeWindowFunctionN "regr_count"

87+ regrIntercept = unsafeWindowFunctionN "regr_intercept"

88+ regrR2 = unsafeWindowFunctionN "regr_r2"

89+ regrSlope = unsafeWindowFunctionN "regr_slope"

90+ regrSxx = unsafeWindowFunctionN "regr_sxx"

91+ regrSxy = unsafeWindowFunctionN "regr_sxy"

92+ regrSyy = unsafeWindowFunctionN "regr_syy"

93+ stddev = unsafeWindowFunction1 "stddev"

94+ stddevPop = unsafeWindowFunction1 "stddev_pop"

95+ stddevSamp = unsafeWindowFunction1 "stddev_samp"

96+ variance = unsafeWindowFunction1 "variance"

97+ varPop = unsafeWindowFunction1 "var_pop"

98+ varSamp = unsafeWindowFunction1 "var_samp"

99+

100+-- | A `WindowDefinition` is a set of table rows that are somehow related

101+-- to the current row

102+data WindowDefinition outer commons grp schemas params from where

103+ WindowDefinition

104+ :: SOP.SListI bys

105+ => NP (Expression outer commons grp schemas params from) bys

106+ -- ^ `partitionBy` clause

107+ -> [SortExpression outer commons grp schemas params from]

108+ -- ^ `Squeal.PostgreSQL.Expression.Sort.orderBy` clause

109+ -> WindowDefinition outer commons grp schemas params from

110+

111+instance OrderBy WindowDefinition where

112+ orderBy sortsR (WindowDefinition parts sortsL)

113+ = WindowDefinition parts (sortsL ++ sortsR)

114+

115+instance RenderSQL (WindowDefinition outer commons schemas from grp params) where

116+ renderSQL (WindowDefinition part ord) =

117+ renderPartitionByClause part <> renderOrderByClause ord

118+ where

119+ renderPartitionByClause = \case

120+ Nil -> ""

121+ parts -> "PARTITION" <+> "BY" <+> renderCommaSeparated renderExpression parts

122+ renderOrderByClause = \case

123+ [] -> ""

124+ srts -> " ORDER" <+> "BY"

125+ <+> commaSeparated (renderSQL <$> srts)

126+

127+{- |

128+The `partitionBy` clause within `Squeal.PostgreSQL.Query.Over` divides the rows into groups,

129+or partitions, that share the same values of the `partitionBy` `Expression`(s).

130+For each row, the window function is computed across the rows that fall into

131+the same partition as the current row.

132+-}

133+partitionBy

134+ :: SOP.SListI bys

135+ => NP (Expression outer commons grp schemas params from) bys -- ^ partitions

136+ -> WindowDefinition outer commons grp schemas params from

137+partitionBy bys = WindowDefinition bys []

138+

139+{- |

140+A window function performs a calculation across a set of table rows

141+that are somehow related to the current row. This is comparable to the type

142+of calculation that can be done with an aggregate function.

143+However, window functions do not cause rows to become grouped into a single

144+output row like non-window aggregate calls would.

145+Instead, the rows retain their separate identities.

146+Behind the scenes, the window function is able to access more than

147+just the current row of the query result.

148+-}

149+newtype WindowFunction

150+ (outer :: FromType)

151+ (commons :: FromType)

152+ (grp :: Grouping)

153+ (schemas :: SchemasType)

154+ (params :: [NullityType])

155+ (from :: FromType)

156+ (ty :: NullityType)

157+ = UnsafeWindowFunction { renderWindowFunction :: ByteString }

158+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

159+

160+instance RenderSQL (WindowFunction outer commons grp schemas params from ty) where

161+ renderSQL = renderWindowFunction

162+

163+{- |

164+A @RankNType@ for window functions with no arguments.

165+-}

166+type WinFun0 x

167+ = forall outer commons grp schemas params from

168+ . WindowFunction outer commons grp schemas params from x

169+ -- ^ cannot reference aliases

170+

171+{- |

172+A @RankNType@ for window functions with 1 argument.

173+-}

174+type WinFun1 x y

175+ = forall outer commons grp schemas params from

176+ . Expression outer commons grp schemas params from x

177+ -- ^ input

178+ -> WindowFunction outer commons grp schemas params from y

179+ -- ^ output

180+

181+{- | A @RankNType@ for window functions with a fixed-length

182+list of heterogeneous arguments.

183+Use the `*:` operator to end your argument lists.

184+-}

185+type WinFunN xs y

186+ = forall outer commons grp schemas params from

187+ . NP (Expression outer commons grp schemas params from) xs

188+ -- ^ inputs

189+ -> WindowFunction outer commons grp schemas params from y

190+ -- ^ output

191+

192+-- | escape hatch for defining window functions

193+unsafeWindowFunction1 :: ByteString -> WinFun1 x y

194+unsafeWindowFunction1 fun x

195+ = UnsafeWindowFunction $ fun <> parenthesized (renderSQL x)

196+

197+-- | escape hatch for defining multi-argument window functions

198+unsafeWindowFunctionN :: SOP.SListI xs => ByteString -> WinFunN xs y

199+unsafeWindowFunctionN fun xs = UnsafeWindowFunction $ fun <>

200+ parenthesized (renderCommaSeparated renderSQL xs)

201+

202+{- | rank of the current row with gaps; same as `rowNumber` of its first peer

203+

204+>>> printSQL rank

205+rank()

206+-}

207+rank :: WinFun0 ('NotNull 'PGint8)

208+rank = UnsafeWindowFunction "rank()"

209+

210+{- | number of the current row within its partition, counting from 1

211+

212+>>> printSQL rowNumber

213+row_number()

214+-}

215+rowNumber :: WinFun0 ('NotNull 'PGint8)

216+rowNumber = UnsafeWindowFunction "row_number()"

217+

218+{- | rank of the current row without gaps; this function counts peer groups

219+

220+>>> printSQL denseRank

221+dense_rank()

222+-}

223+denseRank :: WinFun0 ('NotNull 'PGint8)

224+denseRank = UnsafeWindowFunction "dense_rank()"

225+

226+{- | relative rank of the current row: (rank - 1) / (total partition rows - 1)

227+

228+>>> printSQL percentRank

229+percent_rank()

230+-}

231+percentRank :: WinFun0 ('NotNull 'PGfloat8)

232+percentRank = UnsafeWindowFunction "percent_rank()"

233+

234+{- | cumulative distribution: (number of partition rows

235+preceding or peer with current row) / total partition rows

236+

237+>>> printSQL cumeDist

238+cume_dist()

239+-}

240+cumeDist :: WinFun0 ('NotNull 'PGfloat8)

241+cumeDist = UnsafeWindowFunction "cume_dist()"

242+

243+{- | integer ranging from 1 to the argument value,

244+dividing the partition as equally as possible

245+

246+>>> printSQL $ ntile 5

247+ntile(5)

248+-}

249+ntile :: WinFun1 ('NotNull 'PGint4) ('NotNull 'PGint4)

250+ntile = unsafeWindowFunction1 "ntile"

251+

252+{- | returns value evaluated at the row that is offset rows before the current

253+row within the partition; if there is no such row, instead return default

254+(which must be of the same type as value). Both offset and default are

255+evaluated with respect to the current row.

256+-}

257+lag :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty

258+lag = unsafeWindowFunctionN "lag"

259+

260+{- | returns value evaluated at the row that is offset rows after the current

261+row within the partition; if there is no such row, instead return default

262+(which must be of the same type as value). Both offset and default are

263+evaluated with respect to the current row.

264+-}

265+lead :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty

266+lead = unsafeWindowFunctionN "lead"

267+

268+{- | returns value evaluated at the row that is the

269+first row of the window frame

270+-}

271+firstValue :: WinFun1 ty ty

272+firstValue = unsafeWindowFunction1 "first_value"

273+

274+{- | returns value evaluated at the row that is the

275+last row of the window frame

276+-}

277+lastValue :: WinFun1 ty ty

278+lastValue = unsafeWindowFunction1 "last_value"

279+

280+{- | returns value evaluated at the row that is the nth

281+row of the window frame (counting from 1); null if no such row

282+-}

283+nthValue :: WinFunN '[null ty, 'NotNull 'PGint4] ('Null ty)

284+nthValue = unsafeWindowFunctionN "nth_value"

squeal-postgresql/src/Squeal/PostgreSQL/List.hsnew file+112

@@ -0,0 +1,112 @@

1+{-|

2+Module: Squeal.PostgreSQL.List

3+Description: List related types and functions

4+Copyright: (c) Eitan Chatav, 2019

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+Haskell singly-linked lists are very powerful. This module

9+provides functionality for type-level lists, heterogeneous

10+lists and type aligned lists.

11+-}

12+

13+{-# LANGUAGE

14+ DataKinds

15+ , FlexibleContexts

16+ , GADTs

17+ , LambdaCase

18+ , MultiParamTypeClasses

19+ , OverloadedStrings

20+ , PolyKinds

21+ , QuantifiedConstraints

22+ , RankNTypes

23+ , ScopedTypeVariables

24+ , TypeApplications

25+ , TypeFamilies

26+ , TypeOperators

27+ , UndecidableInstances

28+#-}

29+

30+module Squeal.PostgreSQL.List

31+ ( SOP.NP (..)

32+ , (*:)

33+ , Join

34+ , disjoin

35+ , Additional (..)

36+ , Path (..)

37+ , CFunctor (..)

38+ , CFoldable (..)

39+ , CFree (..)

40+ , Elem

41+ , In

42+ , Length

43+ ) where

44+

45+import Control.Category.Free

46+import Data.Function ((&))

47+import Data.Kind

48+import Data.Type.Bool

49+import GHC.TypeLits

50+

51+import Generics.SOP as SOP

52+

53+-- | `Join` is simply promoted `++` and is used in @JOIN@s in

54+-- `Squeal.PostgreSQL.Query.FromClause`s.

55+type family Join xs ys where

56+ Join '[] ys = ys

57+ Join (x ': xs) ys = x ': Join xs ys

58+

59+-- | `disjoin` is a utility function for splitting an `NP` list into pieces.

60+disjoin

61+ :: forall xs ys expr. SListI xs

62+ => NP expr (Join xs ys)

63+ -> (NP expr xs, NP expr ys)

64+disjoin = case sList @xs of

65+ SNil -> \ys -> (Nil, ys)

66+ SCons -> \(x :* xsys) ->

67+ case disjoin xsys of (xs,ys) -> (x :* xs, ys)

68+

69+-- | The `Additional` class is for appending

70+-- type-level list parameterized constructors such as `NP`,

71+-- `Squeal.PostgreSQL.Query.Selection`, and `Squeal.PostgreSQL.Query.FromClause`.

72+class Additional expr where

73+ also :: expr ys -> expr xs -> expr (Join xs ys)

74+instance Additional (NP expr) where

75+ also ys = \case

76+ Nil -> ys

77+ x :* xs -> x :* (xs & also ys)

78+

79+-- | A useful operator for ending an `NP` list of length at least 2 without `Nil`.

80+(*:) :: f x -> f y -> NP f '[x,y]

81+x *: y = x :* y :* Nil

82+infixl 9 *:

83+

84+-- | @Elem@ is a promoted `Data.List.elem`.

85+type family Elem x xs where

86+ Elem x '[] = 'False

87+ Elem x (x ': _) = 'True

88+ Elem x (_ ': x ': _) = 'True

89+ Elem x (_ ': _ ': x ': _) = 'True

90+ Elem x (_ ': _ ': _ ': x ': _) = 'True

91+ Elem x (_ ': _ ': _ ': _ ': x ': _) = 'True

92+ Elem x (_ ': _ ': _ ': _ ': _ ': x ': _) = 'True

93+ Elem x (_ ': xs) = Elem x xs

94+

95+-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

96+type family In x xs :: Constraint where

97+ In x xs = If (Elem x xs) (() :: Constraint)

98+ (TypeError ('ShowType x ':<>: 'Text " is not in " ':<>: 'ShowType xs))

99+

100+{- | Calculate the `Length` of a type level list

101+

102+>>> :kind! Length '[Char,String,Bool,Double]

103+Length '[Char,String,Bool,Double] :: Nat

104+= 4

105+-}

106+type family Length (xs :: [k]) :: Nat where

107+ Length (_ ': _ ': _ ': _ ': _ : xs) = 5 + Length xs

108+ Length (_ ': _ ': _ ': _ : xs) = 4 + Length xs

109+ Length (_ ': _ ': _ : xs) = 3 + Length xs

110+ Length (_ ': _ : xs) = 2 + Length xs

111+ Length (_ : xs) = 1 + Length xs

112+ Length '[] = 0

squeal-postgresql/src/Squeal/PostgreSQL/Manipulation.hs+381−294

@@ -11,65 +11,126 @@ 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,

6080but 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" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL manip

103+

104+{- |

105+The top level `Manipulation_` type is parameterized by a @schemas@ `SchemasType`,

106+against which the query is type-checked, an input @parameters@ Haskell `Type`,

107+and an ouput row Haskell `Type`.

108+

109+A top-level `Manipulation_` can be run

110+using `Squeal.PostgreSQL.PQ.manipulateParams`, or if @parameters = ()@

111+using `Squeal.PostgreSQL.PQ.manipulate`.

112+

113+Generally, @parameters@ will be a Haskell tuple or record whose entries

114+may be referenced using positional

115+`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a

116+Haskell record, whose entries will be targeted using overloaded labels.

117+

118+>>> :set -XDeriveAnyClass -XDerivingStrategies

119+>>> :{

120+data Row a b = Row { col1 :: a, col2 :: b }

121+ deriving stock (GHC.Generic)

122+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

123+:}

124+

63125simple insert:

64126

65127>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]

66128>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

67−>>> type Schemas = (Public Schema)

68129>>> :{

69130let

70− manipulation :: Manipulation (DBof Schemas) '[] '[]

131+ manipulation :: Manipulation_ (Public Schema) () ()

71132 manipulation =

72− insertRow_ #tab (Set 2 `as` #col1 :* Default `as` #col2)

133+ insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))

73134in printSQL manipulation

74135:}

75136INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)

@@ -80,10 +141,9 @@ parameterized insert:

80141>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

81142>>> :{

82143let

83− manipulation :: Manipulation (DBof (Public Schema)) '[ 'NotNull 'PGint4, 'NotNull 'PGint4 ] '[]

144+ manipulation :: Manipulation_ (Public Schema) (Int32, Int32) ()

84145 manipulation =

85− insertRow_ #tab

86− (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2)

146+ insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))

87147in printSQL manipulation

88148:}

89149INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))

@@ -92,9 +152,9 @@ returning insert:

92152

93153>>> :{

94154let

95− manipulation :: Manipulation (DBof (Public Schema)) '[] '["fromOnly" ::: 'NotNull 'PGint4]

155+ manipulation :: Manipulation_ (Public Schema) () (Only Int32)

96156 manipulation =

97− insertRow #tab (Set 2 `as` #col1 :* Set 3 `as` #col2)

157+ insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))

98158 OnConflictDoRaise (Returning (#col1 `as` #fromOnly))

99159in printSQL manipulation

100160:}

@@ -102,29 +162,28 @@ INSERT INTO "tab" ("col1", "col2") VALUES (2, 3) RETURNING "col1" AS "fromOnly"

102162

103163upsert:

104164

105−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]

106−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

165+>>> type CustomersColumns = '["name" ::: 'NoDef :=> 'NotNull 'PGtext, "email" ::: 'NoDef :=> 'NotNull 'PGtext]

166+>>> type CustomersConstraints = '["uq" ::: 'Unique '["name"]]

167+>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]

107168>>> :{

108169let

109− manipulation :: Manipulation (DBof (Public Schema)) '[] '[ "sum" ::: 'NotNull 'PGint4]

170+ manipulation :: Manipulation_ (Public CustomersSchema) () ()

110171 manipulation =

111− insertRows #tab

112− (Set 2 `as` #col1 :* Set 4 `as` #col2)

113− [Set 6 `as` #col1 :* Set 8 `as` #col2]

114− (OnConflictDoUpdate

115− (Set 2 `as` #col1 :* Same `as` #col2)

116− [#col1 .== #col2])

117− (Returning $ (#col1 + #col2) `as` #sum)

172+ insertInto #customers

173+ (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))

174+ (OnConflict (OnConstraint #uq)

175+ (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))

176+ (Returning_ Nil)

118177in printSQL manipulation

119178:}

120−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"

179+INSERT INTO "customers" ("name", "email") VALUES (E'John Smith', E'john@smith.com') ON CONFLICT ON CONSTRAINT "uq" DO UPDATE SET "email" = ("excluded"."email" || (E'; ' || "customers"."email"))

121180

122181query insert:

123182

124183>>> :{

125184let

126− manipulation :: Manipulation (DBof (Public Schema)) '[] '[]

127− manipulation = insertQuery_ #tab (selectStar (from (table #tab)))

185+ manipulation :: Manipulation_ (Public Schema) () ()

186+ manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))

128187in printSQL manipulation

129188:}

130189INSERT INTO "tab" SELECT * FROM "tab" AS "tab"

@@ -133,10 +192,8 @@ update:

133192

134193>>> :{

135194let

136− manipulation :: Manipulation (DBof (Public Schema)) '[] '[]

137− manipulation =

138− update_ #tab (Set 2 `as` #col1 :* Same `as` #col2)

139− (#col1 ./= #col2)

195+ manipulation :: Manipulation_ (Public Schema) () ()

196+ manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)

140197in printSQL manipulation

141198:}

142199UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")

@@ -145,185 +202,178 @@ delete:

145202

146203>>> :{

147204let

148− manipulation :: Manipulation (DBof (Public Schema)) '[]

149− '[ "col1" ::: 'NotNull 'PGint4

150− , "col2" ::: 'NotNull 'PGint4 ]

151− manipulation = deleteFrom #tab (#col1 .== #col2) ReturningStar

205+ manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)

206+ manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)

152207in printSQL manipulation

153208:}

154209DELETE FROM "tab" WHERE ("col1" = "col2") RETURNING *

155210

211+delete and using clause:

212+

213+>>> :{

214+type Schema3 =

215+ '[ "tab" ::: 'Table ('[] :=> Columns)

216+ , "other_tab" ::: 'Table ('[] :=> Columns)

217+ , "third_tab" ::: 'Table ('[] :=> Columns) ]

218+:}

219+

220+>>> :{

221+let

222+ manipulation :: Manipulation_ (Public Schema3) () ()

223+ manipulation =

224+ deleteFrom #tab (Using (table #other_tab & also (table #third_tab)))

225+ ( (#tab ! #col2 .== #other_tab ! #col2)

226+ .&& (#tab ! #col2 .== #third_tab ! #col2) )

227+ (Returning_ Nil)

228+in printSQL manipulation

229+:}

230+DELETE FROM "tab" USING "other_tab" AS "other_tab", "third_tab" AS "third_tab" WHERE (("tab"."col2" = "other_tab"."col2") AND ("tab"."col2" = "third_tab"."col2"))

231+

156232with manipulation:

157233

158234>>> type ProductsColumns = '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

159235>>> type ProductsSchema = '["products" ::: 'Table ('[] :=> ProductsColumns), "products_deleted" ::: 'Table ('[] :=> ProductsColumns)]

160236>>> :{

161237let

162− manipulation :: Manipulation (DBof (Public ProductsSchema)) '[ 'NotNull 'PGdate] '[]

238+ manipulation :: Manipulation_ (Public ProductsSchema) (Only Day) ()

163239 manipulation = with

164− (deleteFrom #products (#date .< param @1) ReturningStar `as` #del)

165− (insertQuery_ #products_deleted (selectStar (from (common (#del)))))

240+ (deleteFrom #products NoUsing (#date .< param @1) (Returning Star) `as` #del)

241+ (insertInto_ #products_deleted (Subquery (select Star (from (common #del)))))

166242in printSQL manipulation

167243:}

168244WITH "del" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "del" AS "del"

169245-}

170−

171−newtype Manipulation

172− (db :: DBType)

173− (params :: [NullityType])

174− (columns :: RowType)

175− = UnsafeManipulation { renderManipulation :: ByteString }

176− deriving (GHC.Generic,Show,Eq,Ord,NFData)

177−instance RenderSQL (Manipulation db params columns) where

178− renderSQL = renderManipulation

179−instance With Manipulation where

180− with Done manip = UnsafeManipulation $ renderManipulation manip

181− with (cte :>> ctes) manip = UnsafeManipulation $

182− "WITH" <+> renderCommonTableExpressions renderManipulation cte ctes

183− <+> renderManipulation manip

246+type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where

247+ Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)

184248

185249-- | Convert a `Query` into a `Manipulation`.

186250queryStatement

187− :: Query db params columns

188− -> Manipulation db params columns

189−queryStatement q = UnsafeManipulation $ renderQuery q

251+ :: Query '[] commons schemas params columns

252+ -- ^ `Query` to embed as a `Manipulation`

253+ -> Manipulation commons schemas params columns

254+queryStatement q = UnsafeManipulation $ renderSQL q

190255

191256{-----------------------------------------

192257INSERT statements

193258-----------------------------------------}

194259

195−-- | Insert multiple rows.

196−--

197−-- When a table is created, it contains no data. The first thing to do

198−-- before a database can be of much use is to insert data. Data is

199−-- conceptually inserted one row at a time. Of course you can also insert

200−-- more than one row, but there is no way to insert less than one row.

201−-- Even if you know only some column values, a complete row must be created.

202−insertRows

203− :: ( SOP.SListI columns

204− , SOP.SListI results

205− , db ~ (commons :=> schemas)

206− , Has sch schemas schema

207− , Has tab schema ('Table table)

208− , row ~ TableToRow table

209− , columns ~ TableToColumns table )

210− => QualifiedAlias sch tab -- ^ table to insert into

211− -> NP (Aliased (ColumnValue db '[] params)) columns -- ^ row to insert

212− -> [NP (Aliased (ColumnValue db '[] params)) columns] -- ^ more rows to insert

213− -> ConflictClause db table params

214− -- ^ what to do in case of constraint conflict

215− -> ReturningClause db params row results -- ^ results to return

216− -> Manipulation db params results

217−insertRows tab rw rws conflict returning = UnsafeManipulation $

218− "INSERT" <+> "INTO" <+> renderQualifiedAlias tab

219− <+> parenthesized (renderCommaSeparated renderAliasPart rw)

220− <+> "VALUES"

221− <+> commaSeparated

222− ( parenthesized

223− . renderCommaSeparated renderColumnValuePart <$> rw:rws )

224− <> renderConflictClause conflict

225− <> renderReturningClause returning

226− where

227− renderAliasPart, renderColumnValuePart

228− :: Aliased (ColumnValue db '[] params) ty -> ByteString

229− renderAliasPart (_ `As` name) = renderAlias name

230− renderColumnValuePart (value `As` _) = case value of

231− Default -> "DEFAULT"

232− Set expression -> renderExpression expression

233−

234−-- | Insert a single row.

235−insertRow

236− :: ( SOP.SListI columns

237− , SOP.SListI results

238− , db ~ (commons :=> schemas)

239− , Has sch schemas schema

240− , Has tab schema ('Table table)

241− , row ~ TableToRow table

242− , columns ~ TableToColumns table )

243− => QualifiedAlias sch tab -- ^ table to insert into

244− -> NP (Aliased (ColumnValue db '[] params)) columns -- ^ row to insert

245− -> ConflictClause db table params

246− -- ^ what to do in case of constraint conflict

247− -> ReturningClause db params row results -- ^ results to return

248− -> Manipulation db params results

249−insertRow tab rw = insertRows tab rw []

250−

251−-- | Insert multiple rows returning `Nil` and raising an error on conflicts.

252−insertRows_

253− :: ( SOP.SListI columns

254− , db ~ (commons :=> schemas)

255− , Has sch schemas schema

256− , Has tab schema ('Table table)

257− , columns ~ TableToColumns table )

258− => QualifiedAlias sch tab -- ^ table to insert into

259− -> NP (Aliased (ColumnValue db '[] params)) columns -- ^ row to insert

260− -> [NP (Aliased (ColumnValue db '[] params)) columns] -- ^ more rows to insert

261− -> Manipulation db params '[]

262−insertRows_ tab rw rws =

263− insertRows tab rw rws OnConflictDoRaise (Returning Nil)

264−

265−-- | Insert a single row returning `Nil` and raising an error on conflicts.

266−insertRow_

267− :: ( SOP.SListI columns

268− , db ~ (commons :=> schemas)

269− , Has sch schemas schema

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

270269 , Has tab schema ('Table table)

271− , columns ~ TableToColumns table )

272− => QualifiedAlias sch tab -- ^ table to insert into

273− -> NP (Aliased (ColumnValue db '[] params)) columns -- ^ row to insert

274− -> Manipulation db params '[]

275−insertRow_ tab rw = insertRow tab rw OnConflictDoRaise (Returning Nil)

276−

277−-- | Insert a `Query`.

278−insertQuery

279− :: ( SOP.SListI columns

280− , SOP.SListI results

281− , db ~ (commons :=> schemas)

282− , Has sch schemas schema

270+ , columns ~ TableToColumns table

271+ , row0 ~ TableToRow table

272+ , SOP.SListI columns

273+ , SOP.SListI row1 )

274+ => QualifiedAlias sch tab

275+ -- ^ table

276+ -> QueryClause commons schemas params columns

277+ -- ^ what to insert

278+ -> ConflictClause tab commons schemas params table

279+ -- ^ what to do in case of conflict

280+ -> ReturningClause commons schemas params '[tab ::: row0] row1

281+ -- ^ what to return

282+ -> Manipulation commons schemas params row1

283+insertInto tab qry conflict ret = UnsafeManipulation $

284+ "INSERT" <+> "INTO" <+> renderSQL tab

285+ <+> renderSQL qry

286+ <> renderSQL conflict

287+ <> renderSQL ret

288+

289+-- | Like `insertInto` but with `OnConflictDoRaise` and `no` `ReturningClause`.

290+insertInto_

291+ :: ( Has sch schemas schema

283292 , Has tab schema ('Table table)

293+ , columns ~ TableToColumns table

284294 , row ~ TableToRow table

285− , columns ~ TableToColumns table )

286− => QualifiedAlias sch tab -- ^ table to insert into

287− -> Query db params (TableToRow table)

288− -> ConflictClause db table params

289− -- ^ what to do in case of constraint conflict

290− -> ReturningClause db params row results -- ^ results to return

291− -> Manipulation db params results

292−insertQuery tab query conflict returning = UnsafeManipulation $

293− "INSERT" <+> "INTO" <+> renderQualifiedAlias tab

294− <+> renderQuery query

295− <> renderConflictClause conflict

296− <> renderReturningClause returning

297−

298−-- | Insert a `Query` returning `Nil` and raising an error on conflicts.

299−insertQuery_

300− :: ( SOP.SListI columns

301− , db ~ (commons :=> schemas)

302− , Has sch schemas schema

303− , Has tab schema ('Table table)

304− , columns ~ TableToColumns table )

305− => QualifiedAlias sch tab -- ^ table to insert into

306− -> Query db params (TableToRow table)

307− -> Manipulation db params '[]

308−insertQuery_ tab query =

309− insertQuery tab query OnConflictDoRaise (Returning Nil)

310−

311−-- | `ColumnValue`s are values to insert or update in a row.

312−-- `Same` updates with the same value.

313−-- `Default` inserts or updates with the @DEFAULT@ value.

314−-- `Set` sets a value to be an `Expression`, which can refer to

315−-- existing value in the row for an update.

316−data ColumnValue

317− (db :: DBType)

318− (columns :: RowType)

319− (params :: [NullityType])

320− (ty :: ColumnType)

321− where

322− Same :: ColumnValue db (column ': columns) params ty

323− Default :: ColumnValue db columns params ('Def :=> ty)

324− Set

325− :: (forall table. Expression db '[table ::: columns] 'Ungrouped params ty)

326− -> ColumnValue db columns params (constraint :=> ty)

295+ , SOP.SListI columns )

296+ => QualifiedAlias sch tab

297+ -- ^ table

298+ -> QueryClause commons schemas params columns

299+ -- ^ what to insert

300+ -> Manipulation commons schemas params '[]

301+insertInto_ tab qry =

302+ insertInto tab qry OnConflictDoRaise (Returning_ Nil)

303+

304+-- | A `QueryClause` describes what to `insertInto` a table.

305+data QueryClause commons schemas params columns where

306+ Values

307+ :: SOP.SListI columns

308+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns

309+ -- ^ row of values

310+ -> [NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns]

311+ -- ^ additional rows of values

312+ -> QueryClause commons schemas params columns

313+ Select

314+ :: SOP.SListI columns

315+ => NP (Aliased (Optional (Expression '[] commons grp schemas params from))) columns

316+ -- ^ row of values

317+ -> TableExpression '[] commons grp schemas params from

318+ -- ^ from a table expression

319+ -> QueryClause commons schemas params columns

320+ Subquery

321+ :: ColumnsToRow columns ~ row

322+ => Query '[] commons schemas params row

323+ -- ^ subquery to insert

324+ -> QueryClause commons schemas params columns

325+

326+instance RenderSQL (QueryClause commons schemas params columns) where

327+ renderSQL = \case

328+ Values row0 rows ->

329+ parenthesized (renderCommaSeparated renderSQLPart row0)

330+ <+> "VALUES"

331+ <+> commaSeparated

332+ ( parenthesized

333+ . renderCommaSeparated renderValuePart <$> row0 : rows )

334+ Select row0 tab ->

335+ parenthesized (renderCommaSeparatedMaybe renderSQLPartMaybe row0)

336+ <+> "SELECT"

337+ <+> renderCommaSeparatedMaybe renderValuePartMaybe row0

338+ <+> renderSQL tab

339+ Subquery qry -> renderQuery qry

340+ where

341+ renderSQLPartMaybe, renderValuePartMaybe

342+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

343+ -> Maybe ByteString

344+ renderSQLPartMaybe = \case

345+ Default `As` _ -> Nothing

346+ Set _ `As` name -> Just $ renderSQL name

347+ renderValuePartMaybe = \case

348+ Default `As` _ -> Nothing

349+ Set value `As` _ -> Just $ renderExpression value

350+ renderSQLPart, renderValuePart

351+ :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

352+ -> ByteString

353+ renderSQLPart (_ `As` name) = renderSQL name

354+ renderValuePart (value `As` _) = renderSQL value

355+

356+-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s

357+-- whose `ColumnsType` must match the tables'.

358+pattern Values_

359+ :: SOP.SListI columns

360+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns

361+ -- ^ row of values

362+ -> QueryClause commons schemas params columns

363+pattern Values_ vals = Values vals []

364+

365+-- | `Optional` is either `Default` or a value, parameterized by an appropriate

366+-- `ColumnConstraint`.

367+data Optional expr ty where

368+ -- | Use the `Default` value for a column.

369+ Default :: Optional expr ('Def :=> ty)

370+ -- | `Set` a value for a column.

371+ Set :: expr ty -> Optional expr (def :=> ty)

372+

373+instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where

374+ renderSQL = \case

375+ Default -> "DEFAULT"

376+ Set expr -> renderSQL expr

327377

328378-- | A `ReturningClause` computes and return value(s) based

329379-- on each row actually inserted, updated or deleted. This is primarily

@@ -331,74 +381,100 @@ data ColumnValue

331381-- serial sequence number. However, any expression using the table's columns

332382-- is allowed. Only rows that were successfully inserted or updated or

333383-- deleted will be returned. For example, if a row was locked

334−-- but not updated because an `OnConflictDoUpdate` condition was not satisfied,

335−-- the row will not be returned. `ReturningStar` will return all columns

336−-- in the row. Use @Returning Nil@ in the common case where no return

384+-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,

385+-- the row will not be returned. `Returning` `Star` will return all columns

386+-- in the row. Use `Returning` `Nil` in the common case where no return

337387-- values are desired.

338−data ReturningClause

339− (db :: DBType)

340− (params :: [NullityType])

341− (row0 :: RowType)

342− (row1 :: RowType)

343− where

344− ReturningStar

345− :: ReturningClause db params row row

346− Returning

347− :: NP (Aliased (Expression db '[table ::: row0] 'Ungrouped params)) row1

348− -> ReturningClause db params row0 row1

349−

350−-- | Render a `ReturningClause`.

351−renderReturningClause

352− :: SOP.SListI results

353− => ReturningClause db params columns results

354− -> ByteString

355−renderReturningClause = \case

356− ReturningStar -> " RETURNING *"

357− Returning Nil -> ""

358− Returning results -> " RETURNING"

359− <+> renderCommaSeparated (renderAliasedAs renderExpression) results

388+newtype ReturningClause commons schemas params from row =

389+ Returning (Selection '[] commons 'Ungrouped schemas params from row)

390+

391+instance RenderSQL (ReturningClause commons schemas params from row) where

392+ renderSQL = \case

393+ Returning (List Nil) -> ""

394+ Returning selection -> " RETURNING" <+> renderSQL selection

395+

396+-- | `Returning` a `List`

397+pattern Returning_

398+ :: SOP.SListI row

399+ => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row

400+ -- ^ row of values

401+ -> ReturningClause commons schemas params from row

402+pattern Returning_ list = Returning (List list)

360403

361404-- | A `ConflictClause` specifies an action to perform upon a constraint

362405-- violation. `OnConflictDoRaise` will raise an error.

363−-- `OnConflictDoNothing` simply avoids inserting a row.

364−-- `OnConflictDoUpdate` updates the existing row that conflicts with the row

406+-- `OnConflict` `DoNothing` simply avoids inserting a row.

407+-- `OnConflict` `DoUpdate` updates the existing row that conflicts with the row

365408-- proposed for insertion.

366−data ConflictClause

367− (db :: DBType)

368− (table :: TableType)

369− (params :: [NullityType]) where

370− OnConflictDoRaise :: ConflictClause db table params

371− OnConflictDoNothing :: ConflictClause db table params

372− OnConflictDoUpdate

373− :: (row ~ TableToRow table, columns ~ TableToColumns table)

374− => NP (Aliased (ColumnValue db row params)) columns

375− -> [Condition db '[t ::: row] 'Ungrouped params]

376− -> ConflictClause db table params

409+data ConflictClause tab commons schemas params table where

410+ OnConflictDoRaise :: ConflictClause tab commons schemas params table

411+ OnConflict

412+ :: ConflictTarget constraints

413+ -- ^ conflict target

414+ -> ConflictAction tab commons schemas params columns

415+ -- ^ conflict action

416+ -> ConflictClause tab commons schemas params (constraints :=> columns)

377417

378418-- | Render a `ConflictClause`.

379−renderConflictClause

380− :: SOP.SListI (TableToColumns table)

381− => ConflictClause db table params

419+instance SOP.SListI (TableToColumns table)

420+ => RenderSQL (ConflictClause tab commons schemas params table) where

421+ renderSQL = \case

422+ OnConflictDoRaise -> ""

423+ OnConflict target action -> " ON CONFLICT"

424+ <+> renderSQL target <+> renderSQL action

425+

426+{- |

427+`ConflictAction` specifies an alternative `OnConflict` action.

428+It can be either `DoNothing`, or a `DoUpdate` clause specifying

429+the exact details of the `update` action to be performed in case of a conflict.

430+The `Set` and WHERE `Condition`s in `OnConflict` `DoUpdate` have access to the

431+existing row using the table's name (or an alias), and to rows proposed

432+for insertion using the special @#excluded@ table.

433+`OnConflict` `DoNothing` simply avoids inserting a row as its alternative action.

434+`OnConflict` `DoUpdate` updates the existing row that conflicts

435+with the row proposed for insertion as its alternative action.

436+-}

437+data ConflictAction tab commons schemas params columns where

438+ DoNothing :: ConflictAction tab commons schemas params columns

439+ DoUpdate

440+ :: ( row ~ ColumnsToRow columns

441+ , SOP.SListI columns

442+ , columns ~ (col0 ': cols)

443+ , SOP.All (HasIn columns) subcolumns

444+ , AllUnique subcolumns )

445+ => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]))) subcolumns

446+ -> [Condition '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]]

447+ -- ^ WHERE `Condition`s

448+ -> ConflictAction tab commons schemas params columns

449+

450+instance RenderSQL (ConflictAction tab commons schemas params columns) where

451+ renderSQL = \case

452+ DoNothing -> "DO NOTHING"

453+ DoUpdate updates whs'

454+ -> "DO UPDATE SET"

455+ <+> renderCommaSeparated renderUpdate updates

456+ <> case whs' of

457+ [] -> ""

458+ wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

459+

460+renderUpdate

461+ :: (forall x. RenderSQL (expr x))

462+ => Aliased (Optional expr) ty

382463 -> ByteString

383−renderConflictClause = \case

384− OnConflictDoRaise -> ""

385− OnConflictDoNothing -> " ON CONFLICT DO NOTHING"

386− OnConflictDoUpdate updates whs'

387− -> " ON CONFLICT DO UPDATE SET"

388− <+> renderCommaSeparatedMaybe renderUpdate updates

389− <> case whs' of

390− [] -> ""

391− wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

392− where

393− renderUpdate

394− :: Aliased (ColumnValue db columns params) column

395− -> Maybe ByteString

396− renderUpdate = \case

397− Same `As` _ -> Nothing

398− Default `As` column -> Just $

399− renderAlias column <+> "=" <+> "DEFAULT"

400− Set expression `As` column -> Just $

401− renderAlias column <+> "=" <+> renderExpression expression

464+renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr

465+

466+-- | A `ConflictTarget` specifies the constraint violation that triggers a

467+-- `ConflictAction`.

468+data ConflictTarget constraints where

469+ OnConstraint

470+ :: Has con constraints constraint

471+ => Alias con

472+ -> ConflictTarget constraints

473+

474+-- | Render a `ConflictTarget`

475+instance RenderSQL (ConflictTarget constraints) where

476+ renderSQL (OnConstraint con) =

477+ "ON" <+> "CONSTRAINT" <+> renderSQL con

402478

403479{-----------------------------------------

404480UPDATE statements

@@ -408,84 +484,95 @@ UPDATE statements

408484-- in all rows that satisfy the condition.

409485update

410486 :: ( SOP.SListI columns

411− , SOP.SListI results

412− , db ~ (commons :=> schemas)

487+ , SOP.SListI row1

413488 , Has sch schemas schema

414489 , Has tab schema ('Table table)

415− , row ~ TableToRow table

416− , columns ~ TableToColumns table )

490+ , row0 ~ TableToRow table

491+ , columns ~ TableToColumns table

492+ , SOP.All (HasIn columns) subcolumns

493+ , AllUnique subcolumns )

417494 => QualifiedAlias sch tab -- ^ table to update

418− -> NP (Aliased (ColumnValue db row params)) columns

495+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns

419496 -- ^ modified values to replace old values

420− -> (forall t. Condition db '[t ::: row] 'Ungrouped params)

497+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]

421498 -- ^ condition under which to perform update on a row

422− -> ReturningClause db params row results -- ^ results to return

423− -> Manipulation db params results

499+ -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

500+ -> Manipulation commons schemas params row1

424501update tab columns wh returning = UnsafeManipulation $

425502 "UPDATE"

426− <+> renderQualifiedAlias tab

503+ <+> renderSQL tab

427504 <+> "SET"

428− <+> renderCommaSeparatedMaybe renderUpdate columns

429− <+> "WHERE" <+> renderExpression wh

430− <> renderReturningClause returning

431− where

432− renderUpdate

433− :: Aliased (ColumnValue db columns params) column

434− -> Maybe ByteString

435− renderUpdate = \case

436− Same `As` _ -> Nothing

437− Default `As` column -> Just $

438− renderAlias column <+> "=" <+> "DEFAULT"

439− Set expression `As` column -> Just $

440− renderAlias column <+> "=" <+> renderExpression expression

505+ <+> renderCommaSeparated renderUpdate columns

506+ <+> "WHERE" <+> renderSQL wh

507+ <> renderSQL returning

441508

442509-- | Update a row returning `Nil`.

443510update_

444511 :: ( SOP.SListI columns

445− , db ~ (commons :=> schemas)

446512 , Has sch schemas schema

447513 , Has tab schema ('Table table)

448514 , row ~ TableToRow table

449− , columns ~ TableToColumns table )

515+ , columns ~ TableToColumns table

516+ , SOP.All (HasIn columns) subcolumns

517+ , AllUnique subcolumns )

450518 => QualifiedAlias sch tab -- ^ table to update

451− -> NP (Aliased (ColumnValue db row params)) columns

519+ -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns

452520 -- ^ modified values to replace old values

453− -> (forall t. Condition db '[t ::: row] 'Ungrouped params)

521+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

454522 -- ^ condition under which to perform update on a row

455− -> Manipulation db params '[]

456−update_ tab columns wh = update tab columns wh (Returning Nil)

523+ -> Manipulation commons schemas params '[]

524+update_ tab columns wh = update tab columns wh (Returning_ Nil)

457525

458526{-----------------------------------------

459527DELETE statements

460528-----------------------------------------}

461529

462−-- | Delete rows of a table.

530+-- | Specify additional tables with `Using`

531+-- an `also` list of table expressions, allowing columns

532+-- from other tables to appear in the WHERE condition.

533+-- This is similar to the list of tables that can be specified

534+-- in the FROM Clause of a SELECT statement;

535+-- for example, an alias for the table name can be specified.

536+-- Do not repeat the target table in the `Using` list,

537+-- unless you wish to set up a self-join.

538+-- `NoUsing` if no additional tables are to be used.

539+data UsingClause commons schemas params from where

540+ NoUsing :: UsingClause commons schemas params '[]

541+ Using

542+ :: FromClause '[] commons schemas params from

543+ -- ^ what to use

544+ -> UsingClause commons schemas params from

545+

546+-- | Delete rows from a table.

463547deleteFrom

464− :: ( SOP.SListI results

465− , db ~ (commons :=> schemas)

548+ :: ( SOP.SListI row1

466549 , Has sch schemas schema

467550 , Has tab schema ('Table table)

468− , row ~ TableToRow table

551+ , row0 ~ TableToRow table

469552 , columns ~ TableToColumns table )

470553 => QualifiedAlias sch tab -- ^ table to delete from

471− -> Condition db '[tab ::: row] 'Ungrouped params

554+ -> UsingClause commons schemas params from

555+ -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)

472556 -- ^ condition under which to delete a row

473− -> ReturningClause db params row results -- ^ results to return

474− -> Manipulation db params results

475−deleteFrom tab wh returning = UnsafeManipulation $

476− "DELETE FROM" <+> renderQualifiedAlias tab

477− <+> "WHERE" <+> renderExpression wh

478− <> renderReturningClause returning

557+ -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

558+ -> Manipulation commons schemas params row1

559+deleteFrom tab using wh returning = UnsafeManipulation $

560+ "DELETE FROM"

561+ <+> renderSQL tab

562+ <> case using of

563+ NoUsing -> ""

564+ Using tables -> " USING" <+> renderSQL tables

565+ <+> "WHERE" <+> renderSQL wh

566+ <> renderSQL returning

479567

480568-- | Delete rows returning `Nil`.

481569deleteFrom_

482− :: ( db ~ (commons :=> schemas)

483− , Has sch schemas schema

570+ :: ( Has sch schemas schema

484571 , Has tab schema ('Table table)

485572 , row ~ TableToRow table

486573 , columns ~ TableToColumns table )

487574 => QualifiedAlias sch tab -- ^ table to delete from

488− -> (forall t. Condition db '[t ::: row] 'Ungrouped params)

575+ -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

489576 -- ^ condition under which to delete a row

490− -> Manipulation db params '[]

491−deleteFrom_ tab wh = deleteFrom tab wh (Returning Nil)

577+ -> Manipulation commons schemas params '[]

578+deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)

squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+337−187

@@ -8,8 +8,13 @@ Stability: experimental

88This module defines a `Migration` type to safely

99change the schema of your database over time. Let's see an example!

1010

11+First turn on some extensions.

12+

1113>>> :set -XDataKinds -XOverloadedLabels

1214>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators

15+

16+Next, let's define our `TableType`s.

17+

1318>>> :{

1419type UsersTable =

1520 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

@@ -20,7 +25,7 @@ type UsersTable =

2025

2126>>> :{

2227type EmailsTable =

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

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

2429 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]

2530 ] :=>

2631 '[ "id" ::: 'Def :=> 'NotNull 'PGint4

@@ -29,227 +34,293 @@ type EmailsTable =

2934 ]

3035:}

3136

37+Now we can define some `Migration`s to make our tables.

38+

3239>>> :{

3340let

34− makeUsers :: Migration IO (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]

41+ makeUsers :: Migration Definition (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]

3542 makeUsers = Migration

3643 { name = "make users table"

37− , up = void . define $

38− createTable #users

44+ , up = createTable #users

3945 ( serial `as` #id :*

40− (text & notNullable) `as` #name )

46+ notNullable text `as` #name )

4147 ( primaryKey #id `as` #pk_users )

42− , down = void . define $ dropTable #users

48+ , down = dropTable #users

4349 }

4450:}

4551

4652>>> :{

4753let

48− makeEmails :: Migration IO '["public" ::: '["users" ::: 'Table UsersTable]]

54+ makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]

4955 '["public" ::: '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]]

5056 makeEmails = Migration

5157 { name = "make emails table"

52− , up = void . define $

53− createTable #emails

58+ , up = createTable #emails

5459 ( serial `as` #id :*

55− (int & notNullable) `as` #user_id :*

56− (text & nullable) `as` #email )

60+ notNullable int `as` #user_id :*

61+ nullable text `as` #email )

5762 ( primaryKey #id `as` #pk_emails :*

5863 foreignKey #user_id #users #id

5964 OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

60− , down = void . define $ dropTable #emails

65+ , down = dropTable #emails

6166 }

6267:}

6368

64−Now that we have a couple migrations we can chain them together.

69+Now that we have a couple migrations we can chain them together into a `Path`.

6570

6671>>> let migrations = makeUsers :>> makeEmails :>> Done

6772

68−>>> :{

69−let

70− numMigrations

71− :: Has "migrations" schemas MigrationsSchema

72− => PQ schemas schemas IO ()

73− numMigrations = do

74− result <- runQuery (selectStar (from (table (#migrations ! #schema_migrations `as` #m))))

75− num <- ntuples result

76− liftBase $ print num

77−:}

73+Now run the migrations.

7874

75+>>> import Control.Monad.IO.Class

7976>>> :{

8077withConnection "host=localhost port=5432 dbname=exampledb" $

8178 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")

8279 -- suppress notices

80+ & pqThen (liftIO (putStrLn "Migrate"))

8381 & pqThen (migrateUp migrations)

84− & pqThen numMigrations

82+ & pqThen (liftIO (putStrLn "Rollback"))

8583 & pqThen (migrateDown migrations)

86− & pqThen numMigrations

8784:}

88−Row 2

89−Row 0

85+Migrate

86+Rollback

87+

88+We can also create a simple executable using `defaultMain`.

89+

90+>>> let main = defaultMain "host=localhost port=5432 dbname=exampledb" migrations

91+

92+>>> withArgs [] main

93+Invalid command: "". Use:

94+migrate to run all available migrations

95+rollback to rollback all available migrations

96+status to display migrations run and migrations left to run

97+

98+>>> withArgs ["status"] main

99+Migrations already run:

100+ None

101+Migrations left to run:

102+ - make users table

103+ - make emails table

104+

105+>>> withArgs ["migrate"] main

106+Migrations already run:

107+ - make users table

108+ - make emails table

109+Migrations left to run:

110+ None

111+

112+>>> withArgs ["rollback"] main

113+Migrations already run:

114+ None

115+Migrations left to run:

116+ - make users table

117+ - make emails table

118+

119+In addition to enabling `Migration`s using pure SQL `Definition`s for

120+the `up` and `down` instructions, you can also perform impure `IO` actions

121+by using a `Migration`s over the `Terminally` `PQ` `IO` category.

90122-}

91123

92124{-# LANGUAGE

93125 DataKinds

126+ , DeriveGeneric

127+ , FlexibleContexts

128+ , FlexibleInstances

94129 , GADTs

95130 , LambdaCase

96− , PolyKinds

97131 , OverloadedLabels

132+ , OverloadedStrings

133+ , PolyKinds

134+ , QuantifiedConstraints

135+ , RankNTypes

98136 , TypeApplications

99− , FlexibleContexts

100137 , TypeOperators

101138#-}

102139

103140module Squeal.PostgreSQL.Migration

104141 ( -- * Migration

105142 Migration (..)

106− , migrateUp

107− , migrateDown

108− -- * Migration table

143+ , Migratory (..)

144+ , Terminally (..)

145+ , terminally

146+ , pureMigration

109147 , MigrationsTable

110− , createMigrations

111− , insertMigration

112− , deleteMigration

113− , selectMigration

148+ , defaultMain

114149 ) where

115150

151+import Control.Category

116152import Control.Monad

117−import Control.Monad.Base

118−import Control.Monad.Trans.Control

119−import Generics.SOP (K(..))

153+import Data.ByteString (ByteString)

154+import Data.Foldable (traverse_)

120155import Data.Function ((&))

156+import Data.List ((\\))

121157import Data.Text (Text)

158+import Data.Time (UTCTime)

159+import Prelude hiding ((.), id)

160+import System.Environment

161+import UnliftIO (MonadIO (..))

122162

123−import Squeal.PostgreSQL

163+import qualified Data.Text.IO as Text (putStrLn)

164+import qualified Generics.SOP as SOP

165+import qualified GHC.Generics as GHC

124166

125−-- | A `Migration` should contain an inverse pair of

126−-- `up` and `down` instructions and a unique `name`.

127−data Migration io schemas0 schemas1 = Migration

167+import Squeal.PostgreSQL.Alias

168+import Squeal.PostgreSQL.Binary

169+import Squeal.PostgreSQL.Definition

170+import Squeal.PostgreSQL.Definition.Table

171+import Squeal.PostgreSQL.Definition.Table.Constraint

172+import Squeal.PostgreSQL.Expression.Comparison

173+import Squeal.PostgreSQL.Expression.Parameter

174+import Squeal.PostgreSQL.Expression.Time

175+import Squeal.PostgreSQL.Expression.Type

176+import Squeal.PostgreSQL.List

177+import Squeal.PostgreSQL.Manipulation

178+import Squeal.PostgreSQL.PQ

179+import Squeal.PostgreSQL.Query

180+import Squeal.PostgreSQL.Schema

181+import Squeal.PostgreSQL.Transaction

182+

183+-- | A `Migration` is a named "isomorphism" over a given category.

184+-- It should contain an inverse pair of `up` and `down`

185+-- instructions and a unique `name`.

186+data Migration p schemas0 schemas1 = Migration

128187 { name :: Text -- ^ The `name` of a `Migration`.

129188 -- Each `name` in a `Migration` should be unique.

130− , up :: PQ schemas0 schemas1 io () -- ^ The `up` instruction of a `Migration`.

131− , down :: PQ schemas1 schemas0 io () -- ^ The `down` instruction of a `Migration`.

189+ , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.

190+ , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.

191+ } deriving (GHC.Generic)

192+

193+{- |

194+A `Migratory` @p@ is a `Category` for which one can execute or rewind

195+a `Path` of `Migration`s over @p@. This includes the category of pure

196+SQL `Definition`s and the category of impure `Terminally` `PQ` `IO` actions.

197+-}

198+class Category p => Migratory p where

199+

200+ {- |

201+ Run a `Path` of `Migration`s.

202+ Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

203+ In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

204+ if not, `up` the `Migration` and insert its `name` in the `MigrationsTable`.

205+ -}

206+ migrateUp

207+ :: Path (Migration p) schemas0 schemas1

208+ -> PQ schemas0 schemas1 IO ()

209+

210+ {- |

211+ Rewind a `Path` of `Migration`s.

212+ Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

213+ In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

214+ if so, `down` the `Migration` and delete its `name` in the `MigrationsTable`.

215+ -}

216+ migrateDown

217+ :: Path (Migration p) schemas0 schemas1

218+ -> PQ schemas1 schemas0 IO ()

219+

220+instance Migratory Definition where

221+ migrateUp = migrateUp . cmap pureMigration

222+ migrateDown = migrateDown . cmap pureMigration

223+

224+{- | `Terminally` turns an indexed monad transformer and the monad it transforms

225+into a category by restricting the return type to @()@ and permuting the type variables.

226+This is similar to how applying a monad to @()@ yields a monoid.

227+Since a `Terminally` action has a trivial return value, the only reason

228+to run one is for the side effects, in particular database and other IO effects.

229+-}

230+newtype Terminally trans monad x0 x1 = Terminally

231+ { runTerminally :: trans x0 x1 monad () }

232+ deriving GHC.Generic

233+

234+instance

235+ ( IndexedMonadTransPQ trans

236+ , Monad monad

237+ , forall x0 x1. x0 ~ x1 => Monad (trans x0 x1 monad) )

238+ => Category (Terminally trans monad) where

239+ id = Terminally (return ())

240+ Terminally g . Terminally f = Terminally $ pqThen g f

241+

242+-- | `terminally` ignores the output of a computation, returning @()@ and

243+-- wrapping it up into a `Terminally`. You can lift an action in the base monad

244+-- by using @terminally . lift@.

245+terminally

246+ :: Functor (trans x0 x1 monad)

247+ => trans x0 x1 monad ignore

248+ -> Terminally trans monad x0 x1

249+terminally = Terminally . void

250+

251+-- | A `pureMigration` turns a `Migration` involving only pure SQL

252+-- `Definition`s into a `Migration` that may be combined with arbitrary `IO`.

253+pureMigration

254+ :: Migration Definition schemas0 schemas1

255+ -> Migration (Terminally PQ IO) schemas0 schemas1

256+pureMigration migration = Migration

257+ { name = name migration

258+ , up = terminally . define $ up migration

259+ , down = terminally . define $ down migration

132260 }

133261

134−-- | Run `Migration`s by creating the `MigrationsTable`

135−-- if it does not exist and then in a transaction, for each each `Migration`

136−-- query to see if the `Migration` is executed. If not, then

137−-- execute the `Migration` and insert its row in the `MigrationsTable`.

138−migrateUp

139− :: MonadBaseControl IO io

140− => AlignedList (Migration io) schemas0 schemas1 -- ^ migrations to run

141− -> PQ

142− ("migrations" ::: MigrationsSchema ': schemas0)

143− ("migrations" ::: MigrationsSchema ': schemas1)

144− io ()

145−migrateUp migration =

146− define createMigrations

147− & pqBind okResult

148− & pqThen (transactionallySchema_ (upMigrations migration))

149− where

262+instance Migratory (Terminally PQ IO) where

150263

151− upMigrations

152− :: MonadBaseControl IO io

153− => AlignedList (Migration io) schemas0 schemas1

154− -> PQ

155− ("migrations" ::: MigrationsSchema ': schemas0)

156− ("migrations" ::: MigrationsSchema ': schemas1)

157− io ()

158− upMigrations = \case

159− Done -> return ()

160− step :>> steps -> upMigration step & pqThen (upMigrations steps)

161−

162− upMigration

163− :: MonadBase IO io

164− => Migration io schemas0 schemas1 -> PQ

165− ("migrations" ::: MigrationsSchema ': schemas0)

166− ("migrations" ::: MigrationsSchema ': schemas1)

167− io ()

168− upMigration step =

169− queryExecuted step

170− & pqBind (\ executed ->

171− if executed == 1 -- up step has already been executed

172− then PQ (\ _ -> return (K ())) -- unsafely switch schemas

173− else

174− pqEmbed (up step) -- safely switch schemas

175− & pqThen (manipulateParams insertMigration (Only (name step)))

176− -- insert execution record

177− & pqBind okResult)

178−

179− queryExecuted

180− :: MonadBase IO io

181− => Migration io schemas0 schemas1 -> PQ

182− ("migrations" ::: MigrationsSchema ': schemas0)

183− ("migrations" ::: MigrationsSchema ': schemas0)

184− io Row

185− queryExecuted step = do

186− result <- runQueryParams selectMigration (Only (name step))

187− okResult result

188− ntuples result

189−

190−-- | Rewind `Migration`s by creating the `MigrationsTable`

191−-- if it does not exist and then in a transaction, for each each `Migration`

192−-- query to see if the `Migration` is executed. If it is, then

193−-- rewind the `Migration` and delete its row in the `MigrationsTable`.

194−migrateDown

195− :: MonadBaseControl IO io

196− => AlignedList (Migration io) schemas0 schemas1 -- ^ migrations to rewind

197− -> PQ

198− ("migrations" ::: MigrationsSchema ': schemas1)

199− ("migrations" ::: MigrationsSchema ': schemas0)

200− io ()

201−migrateDown migrations =

202− define createMigrations

203− & pqBind okResult

204− & pqThen (transactionallySchema_ (downMigrations migrations))

205− where

264+ migrateUp migration = unsafePQ . transactionally_ $ do

265+ define createMigrations

266+ upMigrations migration

267+

268+ where

269+

270+ upMigrations

271+ :: Path (Migration (Terminally PQ IO)) schemas0 schemas1

272+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

273+ upMigrations = \case

274+ Done -> return ()

275+ step :>> steps -> upMigration step >> upMigrations steps

276+

277+ upMigration

278+ :: Migration (Terminally PQ IO) schemas0 schemas1

279+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

280+ upMigration step = do

281+ executed <- queryExecuted step

282+ unless (executed == 1) $ do

283+ unsafePQ . runTerminally $ up step

284+ manipulateParams_ insertMigration (Only (name step))

285+

286+ queryExecuted

287+ :: Migration (Terminally PQ IO) schemas0 schemas1

288+ -> PQ MigrationsSchemas MigrationsSchemas IO Row

289+ queryExecuted step = do

290+ result <- runQueryParams selectMigration (Only (name step))

291+ ntuples result

206292

207− downMigrations

208− :: MonadBaseControl IO io

209− => AlignedList (Migration io) schemas0 schemas1 -> PQ

210− ("migrations" ::: MigrationsSchema ': schemas1)

211− ("migrations" ::: MigrationsSchema ': schemas0)

212− io ()

213− downMigrations = \case

214− Done -> return ()

215− step :>> steps -> downMigrations steps & pqThen (downMigration step)

216−

217− downMigration

218− :: MonadBase IO io

219− => Migration io schemas0 schemas1 -> PQ

220− ("migrations" ::: MigrationsSchema ': schemas1)

221− ("migrations" ::: MigrationsSchema ': schemas0)

222− io ()

223− downMigration step =

224− queryExecuted step

225− & pqBind (\ executed ->

226− if executed == 0 -- up step has not been executed

227− then PQ (\ _ -> return (K ())) -- unsafely switch schemas

228− else

229− pqEmbed (down step) -- safely switch schemas

230− & pqThen (manipulateParams deleteMigration (Only (name step)))

231− -- delete execution record

232− & pqBind okResult)

233−

234− queryExecuted

235− :: MonadBase IO io

236− => Migration io schemas0 schemas1 -> PQ

237− ("migrations" ::: MigrationsSchema ': schemas1)

238− ("migrations" ::: MigrationsSchema ': schemas1)

239− io Row

240− queryExecuted step = do

241− result <- runQueryParams selectMigration (Only (name step))

242− okResult result

243− ntuples result

244−

245−okResult :: MonadBase IO io => K Result results -> PQ schema schema io ()

246−okResult result = do

247− status <- resultStatus result

248− when (not (status `elem` [CommandOk, TuplesOk])) $ do

249− errorMessageMaybe <- resultErrorMessage result

250− case errorMessageMaybe of

251− Nothing -> error "migrateDown: unknown error"

252− Just msg -> error ("migrationDown: " <> show msg)

293+ migrateDown migrations = unsafePQ . transactionally_ $ do

294+ define createMigrations

295+ downMigrations migrations

296+

297+ where

298+

299+ downMigrations

300+ :: Path (Migration (Terminally PQ IO)) schemas0 schemas1

301+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

302+ downMigrations = \case

303+ Done -> return ()

304+ step :>> steps -> downMigrations steps >> downMigration step

305+

306+ downMigration

307+ :: Migration (Terminally PQ IO) schemas0 schemas1

308+ -> PQ MigrationsSchemas MigrationsSchemas IO ()

309+ downMigration step = do

310+ executed <- queryExecuted step

311+ unless (executed == 0) $ do

312+ unsafePQ . runTerminally $ down step

313+ manipulateParams_ deleteMigration (Only (name step))

314+

315+ queryExecuted

316+ :: Migration (Terminally PQ IO) schemas0 schemas1

317+ -> PQ MigrationsSchemas MigrationsSchemas IO Row

318+ queryExecuted step = do

319+ result <- runQueryParams selectMigration (Only (name step))

320+ ntuples result

321+

322+unsafePQ :: (Functor m) => PQ db0 db1 m x -> PQ db0' db1' m x

323+unsafePQ (PQ pq) = PQ $ fmap (SOP.K . SOP.unK) . pq . SOP.K . SOP.unK

253324

254325-- | The `TableType` for a Squeal migration.

255326type MigrationsTable =

@@ -258,41 +329,120 @@ type MigrationsTable =

258329 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz

259330 ]

260331

332+data MigrationRow =

333+ MigrationRow { migrationName :: Text

334+ , migrationTime :: UTCTime }

335+ deriving (GHC.Generic, Show)

336+

337+instance SOP.Generic MigrationRow

338+instance SOP.HasDatatypeInfo MigrationRow

339+

261340type MigrationsSchema = '["schema_migrations" ::: 'Table MigrationsTable]

341+type MigrationsSchemas = Public MigrationsSchema

262342

263343-- | Creates a `MigrationsTable` if it does not already exist.

264−createMigrations

265− :: Has "migrations" schemas MigrationsSchema

266− => Definition schemas schemas

344+createMigrations :: Definition MigrationsSchemas MigrationsSchemas

267345createMigrations =

268− createSchemaIfNotExists #migrations >>>

269− createTableIfNotExists (#migrations ! #schema_migrations)

346+ createTableIfNotExists #schema_migrations

270347 ( (text & notNullable) `as` #name :*

271348 (timestampWithTimeZone & notNullable & default_ currentTimestamp)

272349 `as` #executed_at )

273350 ( unique #name `as` #migrations_unique_name )

274351

275−-- | Inserts a `Migration` into the `MigrationsTable`

276−insertMigration

277− :: Has "migrations" schemas MigrationsSchema

278− => Manipulation ('[] :=> schemas) '[ 'NotNull 'PGtext] '[]

279−insertMigration = insertRow_ (#migrations ! #schema_migrations)

280− ( Set (param @1) `as` #name :*

281− Default `as` #executed_at )

352+-- | Inserts a `Migration` into the `MigrationsTable`, returning

353+-- the time at which it was inserted.

354+insertMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

355+insertMigration = insertInto_ #schema_migrations

356+ (Values_ (Set (param @1) `as` #name :* Default `as` #executed_at))

282357

283−-- | Deletes a `Migration` from the `MigrationsTable`

284−deleteMigration

285− :: Has "migrations" schemas MigrationsSchema

286− => Manipulation ('[] :=> schemas) '[ 'NotNull 'PGtext ] '[]

287−deleteMigration = deleteFrom_ (#migrations ! #schema_migrations) (#name .== param @1)

358+-- | Deletes a `Migration` from the `MigrationsTable`, returning

359+-- the time at which it was inserted.

360+deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

361+deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)

288362

289363-- | Selects a `Migration` from the `MigrationsTable`, returning

290−-- the time at which it was executed.

364+-- the time at which it was inserted.

291365selectMigration

292− :: Has "migrations" schemas MigrationsSchema

293− => Query ('[] :=> schemas) '[ 'NotNull 'PGtext ]

294− '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]

295−selectMigration = select

296− (#executed_at `as` #executed_at)

297− ( from (table ((#migrations ! #schema_migrations) `as` #m))

298− & where_ (#name .== param @1))

366+ :: Query_ MigrationsSchemas (Only Text) (Only UTCTime)

367+selectMigration = select_ (#executed_at `as` #fromOnly)

368+ $ from (table (#schema_migrations))

369+ & where_ (#name .== param @1)

370+

371+selectMigrations :: Query_ MigrationsSchemas () MigrationRow

372+selectMigrations = select_

373+ (#name `as` #migrationName :* #executed_at `as` #migrationTime)

374+ (from (table #schema_migrations))

375+

376+data MigrateCommand

377+ = MigrateStatus

378+ | MigrateUp

379+ | MigrateDown deriving (GHC.Generic, Show)

380+

381+{- | `defaultMain` creates a simple executable

382+from a connection string and a list of `Migration`s. -}

383+defaultMain

384+ :: Migratory p

385+ => ByteString

386+ -- ^ connection string

387+ -> Path (Migration p) db0 db1

388+ -- ^ migrations

389+ -> IO ()

390+defaultMain connectTo migrations = do

391+ command <- readCommandFromArgs

392+ maybe (pure ()) performCommand command

393+

394+ where

395+

396+ performCommand :: MigrateCommand -> IO ()

397+ performCommand = \case

398+ MigrateStatus -> withConnection connectTo $

399+ suppressNotices >> migrateStatus

400+ MigrateUp -> withConnection connectTo $

401+ suppressNotices & pqThen (migrateUp migrations) & pqThen migrateStatus

402+ MigrateDown -> withConnection connectTo $

403+ suppressNotices & pqThen (migrateDown migrations) & pqThen migrateStatus

404+

405+ migrateStatus :: PQ schema schema IO ()

406+ migrateStatus = unsafePQ $ do

407+ runNames <- getRunMigrationNames

408+ let names = ctoList name migrations

409+ unrunNames = names \\ runNames

410+ liftIO $ displayRunned runNames >> displayUnrunned unrunNames

411+

412+ suppressNotices :: PQ schema schema IO ()

413+ suppressNotices = manipulate_ $

414+ UnsafeManipulation "SET client_min_messages TO WARNING;"

415+

416+ readCommandFromArgs :: IO (Maybe MigrateCommand)

417+ readCommandFromArgs = getArgs >>= \case

418+ ["migrate"] -> pure . Just $ MigrateUp

419+ ["rollback"] -> pure . Just $ MigrateDown

420+ ["status"] -> pure . Just $ MigrateStatus

421+ args -> displayUsage args >> pure Nothing

422+

423+ displayUsage :: [String] -> IO ()

424+ displayUsage args = do

425+ putStrLn $ "Invalid command: \"" <> unwords args <> "\". Use:"

426+ putStrLn "migrate to run all available migrations"

427+ putStrLn "rollback to rollback all available migrations"

428+ putStrLn "status to display migrations run and migrations left to run"

429+

430+ getRunMigrationNames :: (MonadIO m) => PQ db0 db0 m [Text]

431+ getRunMigrationNames =

432+ fmap migrationName <$> (unsafePQ (define createMigrations & pqThen (runQuery selectMigrations)) >>= getRows)

433+

434+ displayListOfNames :: [Text] -> IO ()

435+ displayListOfNames [] = Text.putStrLn " None"

436+ displayListOfNames xs =

437+ let singleName n = Text.putStrLn $ " - " <> n

438+ in traverse_ singleName xs

439+

440+ displayUnrunned :: [Text] -> IO ()

441+ displayUnrunned unrunned =

442+ Text.putStrLn "Migrations left to run:"

443+ >> displayListOfNames unrunned

444+

445+ displayRunned :: [Text] -> IO ()

446+ displayRunned runned =

447+ Text.putStrLn "Migrations already run:"

448+ >> displayListOfNames runned

squeal-postgresql/src/Squeal/PostgreSQL/PG.hsnew file+388

@@ -0,0 +1,388 @@

1+{-|

2+Module: Squeal.PostgreSQL.PG

3+Description: Embedding of Haskell types into Postgres's type system

4+Copyright: (c) Eitan Chatav, 2010

5+Maintainer: eitan@morphism.tech

6+Stability: experimental

8+`Squeal.PostgreSQL.PG` provides type families for turning Haskell

9+`Type`s into corresponding Postgres types.

10+-}

11+{-# LANGUAGE

12+ AllowAmbiguousTypes

13+ , DeriveAnyClass

14+ , DeriveFoldable

15+ , DeriveFunctor

16+ , DeriveGeneric

17+ , DeriveTraversable

18+ , DerivingStrategies

19+ , DefaultSignatures

20+ , FlexibleContexts

21+ , FlexibleInstances

22+ , FunctionalDependencies

23+ , GADTs

24+ , LambdaCase

25+ , MultiParamTypeClasses

26+ , OverloadedStrings

27+ , ScopedTypeVariables

28+ , TypeApplications

29+ , TypeFamilies

30+ , TypeInType

31+ , TypeOperators

32+ , UndecidableInstances

33+ , UndecidableSuperClasses

34+#-}

35+

36+module Squeal.PostgreSQL.PG

37+ ( -- * PG embeddings

38+ PG

39+ , NullPG

40+ , TuplePG

41+ , RowPG

42+ -- * Storage newtypes

43+ , Money (..)

44+ , Json (..)

45+ , Jsonb (..)

46+ , Composite (..)

47+ , Enumerated (..)

48+ , VarArray (..)

49+ , FixArray (..)

50+ , LibPQ.Oid (..)

51+ -- * Type families

52+ , LabelsPG

53+ , DimPG

54+ , FixPG

55+ , TupleOf

56+ , TupleCodeOf

57+ , RowOf

58+ , ConstructorsOf

59+ , ConstructorNameOf

60+ , ConstructorNamesOf

61+ ) where

62+

63+import Data.Aeson (Value)

64+import Data.Kind (Type)

65+import Data.Int (Int16, Int32, Int64)

66+import Data.Scientific (Scientific)

67+import Data.Time (Day, DiffTime, LocalTime, TimeOfDay, TimeZone, UTCTime)

68+import Data.Vector (Vector)

69+import Data.UUID.Types (UUID)

70+import GHC.TypeLits

71+import Network.IP.Addr (NetAddr, IP)

72+

73+import qualified Data.ByteString.Lazy as Lazy (ByteString)

74+import qualified Data.ByteString as Strict (ByteString)

75+import qualified Data.Text.Lazy as Lazy (Text)

76+import qualified Data.Text as Strict (Text)

77+import qualified Database.PostgreSQL.LibPQ as LibPQ

78+import qualified GHC.Generics as GHC

79+import qualified Generics.SOP as SOP

80+import qualified Generics.SOP.Record as SOP

81+import qualified Generics.SOP.Type.Metadata as Type

82+

83+import Squeal.PostgreSQL.Alias

84+import Squeal.PostgreSQL.Schema

85+

86+-- $setup

87+-- >>> import Squeal.PostgreSQL

88+-- >>> import Data.Text (Text)

89+

90+{- | The `PG` type family embeds a subset of Haskell types

91+as Postgres types. As an open type family, `PG` is extensible.

92+

93+>>> :kind! PG LocalTime

94+PG LocalTime :: PGType

95+= 'PGtimestamp

96+

97+>>> newtype MyDouble = My Double

98+>>> :set -XTypeFamilies

99+>>> type instance PG MyDouble = 'PGfloat8

100+-}

101+type family PG (hask :: Type) :: PGType

102+-- | `PGbool`

103+type instance PG Bool = 'PGbool

104+-- | `PGint2`

105+type instance PG Int16 = 'PGint2

106+-- | `PGint4`

107+type instance PG Int32 = 'PGint4

108+-- | `PGint8`

109+type instance PG Int64 = 'PGint8

110+-- | `PGint2`

111+type instance PG LibPQ.Oid = 'PGoid

112+-- | `PGnumeric`

113+type instance PG Scientific = 'PGnumeric

114+-- | `PGfloat4`

115+type instance PG Float = 'PGfloat4

116+-- | `PGfloat8`

117+type instance PG Double = 'PGfloat8

118+-- | `PGchar` @1@

119+type instance PG Char = 'PGchar 1

120+-- | `PGtext`

121+type instance PG Strict.Text = 'PGtext

122+-- | `PGtext`

123+type instance PG Lazy.Text = 'PGtext

124+-- | `PGtext`

125+type instance PG String = 'PGtext

126+-- | `PGbytea`

127+type instance PG Strict.ByteString = 'PGbytea

128+-- | `PGbytea`

129+type instance PG Lazy.ByteString = 'PGbytea

130+-- | `PGtimestamp`

131+type instance PG LocalTime = 'PGtimestamp

132+-- | `PGtimestamptz`

133+type instance PG UTCTime = 'PGtimestamptz

134+-- | `PGdate`

135+type instance PG Day = 'PGdate

136+-- | `PGtime`

137+type instance PG TimeOfDay = 'PGtime

138+-- | `PGtimetz`

139+type instance PG (TimeOfDay, TimeZone) = 'PGtimetz

140+-- | `PGinterval`

141+type instance PG DiffTime = 'PGinterval

142+-- | `PGuuid`

143+type instance PG UUID = 'PGuuid

144+-- | `PGinet`

145+type instance PG (NetAddr IP) = 'PGinet

146+-- | `PGjson`

147+type instance PG Value = 'PGjson

148+

149+{-| The `LabelsPG` type family calculates the constructors of a

150+Haskell enum type.

151+

152+>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

153+>>> instance SOP.Generic Schwarma

154+>>> instance SOP.HasDatatypeInfo Schwarma

155+>>> :kind! LabelsPG Schwarma

156+LabelsPG Schwarma :: [Type.ConstructorName]

157+= '["Beef", "Lamb", "Chicken"]

158+-}

159+type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where

160+ LabelsPG hask =

161+ ConstructorNamesOf (ConstructorsOf (SOP.DatatypeInfoOf hask))

162+

163+{- |

164+`RowPG` turns a Haskell `Type` into a `RowType`.

165+

166+`RowPG` may be applied to normal Haskell record types provided they

167+have `SOP.Generic` and `SOP.HasDatatypeInfo` instances;

168+

169+>>> data Person = Person { name :: Strict.Text, age :: Int32 } deriving GHC.Generic

170+>>> instance SOP.Generic Person

171+>>> instance SOP.HasDatatypeInfo Person

172+>>> :kind! RowPG Person

173+RowPG Person :: [(Symbol, NullityType)]

174+= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

175+-}

176+type family RowPG (hask :: Type) :: RowType where

177+ RowPG hask = RowOf (SOP.RecordCodeOf hask)

178+

179+-- | `RowOf` applies `NullPG` to the fields of a list.

180+type family RowOf (record :: [(Symbol, Type)]) :: RowType where

181+ RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': col4 ::: ty4 ': record) =

182+ col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': col4 ::: NullPG ty4 ': RowOf record

183+ RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': record) =

184+ col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': RowOf record

185+ RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': record) =

186+ col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': RowOf record

187+ RowOf (col ::: ty ': col1 ::: ty1 ': record) =

188+ col ::: NullPG ty ': col1::: NullPG ty1 ': RowOf record

189+ RowOf (col ::: ty ': record) = col ::: NullPG ty ': RowOf record

190+ RowOf '[] = '[]

191+

192+{- | `NullPG` turns a Haskell type into a `NullityType`.

193+

194+>>> :kind! NullPG Double

195+NullPG Double :: NullityType

196+= 'NotNull 'PGfloat8

197+>>> :kind! NullPG (Maybe Double)

198+NullPG (Maybe Double) :: NullityType

199+= 'Null 'PGfloat8

200+-}

201+type family NullPG (hask :: Type) :: NullityType where

202+ NullPG (Maybe hask) = 'Null (PG hask)

203+ NullPG hask = 'NotNull (PG hask)

204+

205+{- | `TuplePG` turns a Haskell tuple type (including record types) into

206+the corresponding list of `NullityType`s.

207+

208+>>> :kind! TuplePG (Double, Maybe Char)

209+TuplePG (Double, Maybe Char) :: [NullityType]

210+= '[ 'NotNull 'PGfloat8, 'Null ('PGchar 1)]

211+-}

212+type family TuplePG (hask :: Type) :: [NullityType] where

213+ TuplePG hask = TupleOf (TupleCodeOf hask (SOP.Code hask))

214+

215+-- | `TupleOf` turns a list of Haskell `Type`s into a list of `NullityType`s.

216+type family TupleOf (tuple :: [Type]) :: [NullityType] where

217+ TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': hask5 ': tuple) =

218+ NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': NullPG hask5 ': TupleOf tuple

219+ TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': tuple) =

220+ NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': TupleOf tuple

221+ TupleOf (hask ': hask1 ': hask2 ': hask3 ': tuple) =

222+ NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': TupleOf tuple

223+ TupleOf (hask ': hask1 ': hask2 ': tuple) =

224+ NullPG hask ': NullPG hask1 ': NullPG hask2 ': TupleOf tuple

225+ TupleOf (hask ': hask1 ': tuple) = NullPG hask ': NullPG hask1 ': TupleOf tuple

226+ TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple

227+ TupleOf '[] = '[]

228+

229+-- | `TupleCodeOf` takes the `SOP.Code` of a haskell `Type`

230+-- and if it's a simple product returns it, otherwise giving a `TypeError`.

231+type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where

232+ TupleCodeOf hask '[tuple] = tuple

233+ TupleCodeOf hask '[] =

234+ TypeError

235+ ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

236+ ':$$: 'Text "It is a void type with no constructors."

237+ )

238+ TupleCodeOf hask (_ ': _ ': _) =

239+ TypeError

240+ ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

241+ ':$$: 'Text "It is a sum type with more than one constructor."

242+ )

243+

244+-- | Calculates constructors of a datatype.

245+type family ConstructorsOf (datatype :: Type.DatatypeInfo)

246+ :: [Type.ConstructorInfo] where

247+ ConstructorsOf ('Type.ADT _module _datatype constructors) =

248+ constructors

249+ ConstructorsOf ('Type.Newtype _module _datatype constructor) =

250+ '[constructor]

251+

252+-- | Calculates the name of a nullary constructor, otherwise

253+-- generates a type error.

254+type family ConstructorNameOf (constructor :: Type.ConstructorInfo)

255+ :: Type.ConstructorName where

256+ ConstructorNameOf ('Type.Constructor name) = name

257+ ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError

258+ ('Text "ConstructorNameOf error: non-nullary constructor "

259+ ':<>: 'Text name)

260+ ConstructorNameOf ('Type.Record name _fields) = TypeError

261+ ('Text "ConstructorNameOf error: non-nullary constructor "

262+ ':<>: 'Text name)

263+

264+-- | Calculate the names of nullary constructors.

265+type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])

266+ :: [Type.ConstructorName] where

267+ ConstructorNamesOf '[] = '[]

268+ ConstructorNamesOf (constructor ': constructors) =

269+ ConstructorNameOf constructor ': ConstructorNamesOf constructors

270+

271+-- | `DimPG` turns Haskell nested homogeneous tuples into a list of lengths.

272+type family DimPG (hask :: Type) :: [Nat] where

273+ DimPG (x,x) = 2 ': DimPG x

274+ DimPG (x,x,x) = 3 ': DimPG x

275+ DimPG (x,x,x,x) = 4 ': DimPG x

276+ DimPG (x,x,x,x,x) = 5 ': DimPG x

277+ DimPG (x,x,x,x,x,x) = 6 ': DimPG x

278+ DimPG (x,x,x,x,x,x,x) = 7 ': DimPG x

279+ DimPG (x,x,x,x,x,x,x,x) = 8 ': DimPG x

280+ DimPG (x,x,x,x,x,x,x,x,x) = 9 ': DimPG x

281+ DimPG (x,x,x,x,x,x,x,x,x,x) = 10 ': DimPG x

282+ DimPG x = '[]

283+

284+-- | `FixPG` extracts `NullPG` of the base type of nested homogeneous tuples.

285+type family FixPG (hask :: Type) :: NullityType where

286+ FixPG (x,x) = FixPG x

287+ FixPG (x,x,x) = FixPG x

288+ FixPG (x,x,x,x) = FixPG x

289+ FixPG (x,x,x,x,x) = FixPG x

290+ FixPG (x,x,x,x,x,x) = FixPG x

291+ FixPG (x,x,x,x,x,x,x) = FixPG x

292+ FixPG (x,x,x,x,x,x,x,x) = FixPG x

293+ FixPG (x,x,x,x,x,x,x,x,x) = FixPG x

294+ FixPG (x,x,x,x,x,x,x,x,x,x) = FixPG x

295+ FixPG (x,x,x,x,x,x,x,x,x,x,x) = FixPG x

296+ FixPG x = NullPG x

297+

298+{- | The `Money` newtype stores a monetary value in terms

299+of the number of cents, i.e. @$2,000.20@ would be expressed as

300+@Money { cents = 200020 }@.

301+

302+>>> import Control.Monad (void)

303+>>> import Control.Monad.IO.Class (liftIO)

304+>>> import Squeal.PostgreSQL

305+>>> :{

306+let

307+ roundTrip :: Query_ (Public '[]) (Only Money) (Only Money)

308+ roundTrip = values_ $ parameter @1 money `as` #fromOnly

309+:}

310+

311+>>> let input = Only (Money 20020)

312+

313+>>> :{

314+withConnection "host=localhost port=5432 dbname=exampledb" $ do

315+ result <- runQueryParams roundTrip input

316+ Just output <- firstRow result

317+ liftIO . print $ input == output

318+:}

319+True

320+-}

321+newtype Money = Money { cents :: Int64 }

322+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

323+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

324+-- | `PGmoney`

325+type instance PG Money = 'PGmoney

326+

327+{- | The `Json` newtype is an indication that the Haskell

328+type it's applied to should be stored as a `PGjson`.

329+-}

330+newtype Json hask = Json {getJson :: hask}

331+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

332+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

333+-- | `PGjson`

334+type instance PG (Json hask) = 'PGjson

335+

336+{- | The `Jsonb` newtype is an indication that the Haskell

337+type it's applied to should be stored as a `PGjsonb`.

338+-}

339+newtype Jsonb hask = Jsonb {getJsonb :: hask}

340+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

341+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

342+-- | `PGjsonb`

343+type instance PG (Jsonb hask) = 'PGjsonb

344+

345+{- | The `Composite` newtype is an indication that the Haskell

346+type it's applied to should be stored as a `PGcomposite`.

347+-}

348+newtype Composite record = Composite {getComposite :: record}

349+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

350+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

351+-- | `PGcomposite` @(@`RowPG` @hask)@

352+type instance PG (Composite hask) = 'PGcomposite (RowPG hask)

353+

354+{- | The `Enumerated` newtype is an indication that the Haskell

355+type it's applied to should be stored as a `PGenum`.

356+-}

357+newtype Enumerated enum = Enumerated {getEnumerated :: enum}

358+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

359+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

360+-- | `PGenum` @(@`LabelsPG` @hask)@

361+type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)

362+

363+{- | The `VarArray` newtype is an indication that the Haskell

364+type it's applied to should be stored as a `PGvararray`.

365+

366+>>> :kind! PG (VarArray (Vector Double))

367+PG (VarArray (Vector Double)) :: PGType

368+= 'PGvararray ('NotNull 'PGfloat8)

369+-}

370+newtype VarArray arr = VarArray {getVarArray :: arr}

371+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

372+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

373+-- | `PGvararray` @(@`NullPG` @hask)@

374+type instance PG (VarArray (Vector hask)) = 'PGvararray (NullPG hask)

375+type instance PG (VarArray [hask]) = 'PGvararray (NullPG hask)

376+

377+{- | The `FixArray` newtype is an indication that the Haskell

378+type it's applied to should be stored as a `PGfixarray`.

379+

380+>>> :kind! PG (FixArray ((Double, Double), (Double, Double)))

381+PG (FixArray ((Double, Double), (Double, Double))) :: PGType

382+= 'PGfixarray '[2, 2] ('NotNull 'PGfloat8)

383+-}

384+newtype FixArray arr = FixArray {getFixArray :: arr}

385+ deriving stock (Eq, Ord, Show, Read, GHC.Generic)

386+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

387+-- | `PGfixarray` @(@`DimPG` @hask) (@`FixPG` @hask)@

388+type instance PG (FixArray hask) = 'PGfixarray (DimPG hask) (FixPG hask)

squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+174−130

@@ -6,7 +6,7 @@ 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

@@ -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

@@ -65,25 +64,30 @@ module Squeal.PostgreSQL.PQ

6564 , resultErrorCode

6665 -- * Exceptions

6766 , SquealException (..)

67+ , PQState (..)

68+ , okResult

6869 , catchSqueal

6970 , handleSqueal

71+ , trySqueal

7072 ) where

7173

72−import Control.Exception.Lifted

73−import Control.Monad.Base

74+import Control.Exception (Exception, throw)

7475import Control.Monad.Except

7576import Control.Monad.Morph

76−import Control.Monad.Trans.Control

77+import UnliftIO (MonadUnliftIO (..), bracket, catch, handle, try)

7778import Data.ByteString (ByteString)

7879import Data.Foldable

7980import Data.Function ((&))

81+import Data.Functor ((<&>))

8082import Data.Kind

8183import Data.Text (pack, Text)

8284import Data.Traversable

8385import Generics.SOP

8486import PostgreSQL.Binary.Encoding (encodingBytes)

8587

88+import qualified Control.Monad.Fail as Fail

8689import qualified Database.PostgreSQL.LibPQ as LibPQ

90+import qualified PostgreSQL.Binary.Encoding as Encoding

8791

8892import Squeal.PostgreSQL.Binary

8993import Squeal.PostgreSQL.Definition

@@ -104,6 +108,9 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict

104108import qualified Control.Monad.Trans.RWS.Lazy as Lazy

105109import qualified Control.Monad.Trans.RWS.Strict as Strict

106110

111+-- $setup

112+-- >>> import Squeal.PostgreSQL

113+

107114{- | Makes a new connection to the database server.

108115

109116This function opens a new database connection using the parameters taken

@@ -131,19 +138,19 @@ with the wrong schema!

131138-}

132139connectdb

133140 :: forall schemas io

134− . MonadBase IO io

141+ . MonadIO io

135142 => ByteString -- ^ conninfo

136143 -> io (K LibPQ.Connection schemas)

137−connectdb = fmap K . liftBase . LibPQ.connectdb

144+connectdb = fmap K . liftIO . LibPQ.connectdb

138145

139146-- | Closes the connection to the server.

140−finish :: MonadBase IO io => K LibPQ.Connection schemas -> io ()

141−finish = liftBase . LibPQ.finish . unK

147+finish :: MonadIO io => K LibPQ.Connection schemas -> io ()

148+finish = liftIO . LibPQ.finish . unK

142149

143150-- | Do `connectdb` and `finish` before and after a computation.

144151withConnection

145152 :: forall schemas0 schemas1 io x

146− . MonadBaseControl IO io

153+ . MonadUnliftIO io

147154 => ByteString

148155 -> PQ schemas0 schemas1 io x

149156 -> io x

@@ -171,7 +178,7 @@ instance Monad m => Functor (PQ schemas0 schemas1 m) where

171178 K x <- pq conn

172179 return $ K (f x)

173180

174−-- | Run a `PQ` and keep the result and the `Connection`.

181+-- | Run a `PQ` and keep the result and the `LibPQ.Connection`.

175182runPQ

176183 :: Functor m

177184 => PQ schemas0 schemas1 m x

@@ -181,7 +188,7 @@ runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn

181188 -- K x <- pq conn

182189 -- return (x, K (unK conn))

183190

184−-- | Execute a `PQ` and discard the result but keep the `Connection`.

191+-- | Execute a `PQ` and discard the result but keep the `LibPQ.Connection`.

185192execPQ

186193 :: Functor m

187194 => PQ schemas0 schemas1 m x

@@ -189,7 +196,7 @@ execPQ

189196 -> m (K LibPQ.Connection schemas1)

190197execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn

191198

192−-- | Evaluate a `PQ` and discard the `Connection` but keep the result.

199+-- | Evaluate a `PQ` and discard the `LibPQ.Connection` but keep the result.

193200evalPQ

194201 :: Functor m

195202 => PQ schemas0 schemas1 m x

@@ -201,8 +208,7 @@ evalPQ (PQ pq) conn = unK <$> pq conn

201208-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).

202209-- An indexed monad transformer transforms a `Monad` into an indexed monad.

203210-- 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`.

211+-- support running `Definition`s using `define`.

206212class IndexedMonadTransPQ pq where

207213

208214 -- | indexed analog of `<*>`

@@ -242,19 +248,16 @@ class IndexedMonadTransPQ pq where

242248 -> x -> pq schemas0 schemas2 m z

243249 pqAndThen g f x = pqBind g (f x)

244250

245− -- | Safely embed a computation in a larger schema.

246− pqEmbed

247− :: Monad m

248− => pq schemas0 schemas1 m x

249− -> pq (schema ': schemas0) (schema : schemas1) m x

250−

251− -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law

251+ -- | Run a `Definition` with `LibPQ.exec`.

252252 --

253− -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@

253+ -- It should be functorial in effect.

254+ --

255+ -- @define id = return ()@

256+ -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@

254257 define

255− :: MonadBase IO io

258+ :: MonadIO io

256259 => Definition schemas0 schemas1

257− -> pq schemas0 schemas1 io (K LibPQ.Result '[])

260+ -> pq schemas0 schemas1 io ()

258261

259262instance IndexedMonadTransPQ PQ where

260263

@@ -267,26 +270,26 @@ instance IndexedMonadTransPQ PQ where

267270 K x' <- x conn

268271 unPQ (f x') (K (unK conn))

269272

270− pqEmbed (PQ pq) = PQ $ \ (K conn) -> do

271− K x <- pq (K conn)

272− return $ K x

273−

274273 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do

275− resultMaybe <- liftBase $ LibPQ.exec conn q

274+ resultMaybe <- liftIO $ LibPQ.exec conn q

276275 case resultMaybe of

277276 Nothing -> throw $ ResultException

278277 "define: LibPQ.exec returned no results"

279− Just result -> return $ K (K result)

278+ Just result -> K <$> okResult_ result

280279

281−{- | `MonadPQ` is an `mtl` style constraint, similar to

282−`Control.Monad.State.Class.MonadState`, for using `LibPQ` to

280+{- | `MonadPQ` is an @mtl@ style constraint, similar to

281+`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to

283282

284283* `manipulateParams` runs a `Manipulation` with params from a type

285284 with a `ToParams` constraint. It calls `LibPQ.execParams` and

286285 doesn't afraid of anything.

287286

287+* `manipulateParams_` is like `manipulateParams` for a returning-free statement.

288+

288289* `manipulate` is like `manipulateParams` for a parameter-free statement.

289290

291+* `manipulate_` is like `manipulate` for a returning-free statement.

292+

290293* `runQueryParams` is like `manipulateParams` for query statements.

291294

292295* `runQuery` is like `runQueryParams` for a parameter-free statement.

@@ -300,11 +303,11 @@ instance IndexedMonadTransPQ PQ where

300303* `forPrepared` is a flipped `traversePrepared`

301304

302305* `traversePrepared_` is like `traversePrepared` but works on `Foldable`

303− containers and returns unit.

306+ containers for a returning-free statement.

304307

305308* `forPrepared_` is a flipped `traversePrepared_`.

306309

307−* `liftPQ` lets you lift actions from `LibPQ` that require a connection

310+* `liftPQ` lets you lift actions from `Database.PostgreSQL.LibPQ` that require a connection

308311 into your monad.

309312

310313To define an instance, you can minimally define only `manipulateParams`,

@@ -314,74 +317,84 @@ a default instance.

314317-}

315318class Monad pq => MonadPQ schemas pq | pq -> schemas where

316319 manipulateParams

317− :: ToParams x params

318− => Manipulation ('[] :=> schemas) params ys

319− -- ^ `insertRows`, `update` or `deleteFrom`

320+ :: (ToParams x params, All OidOfParam params)

321+ => Manipulation '[] schemas params ys

322+ -- ^ `insertInto`, `update` or `deleteFrom`

320323 -> x -> pq (K LibPQ.Result ys)

321324 default manipulateParams

322325 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

323− => ToParams x params

324− => Manipulation ('[] :=> schemas) params ys

325− -- ^ `insertRows`, `update` or `deleteFrom`

326+ => (ToParams x params, All OidOfParam params)

327+ => Manipulation '[] schemas params ys

328+ -- ^ `insertInto`, `update` or `deleteFrom`

326329 -> x -> pq (K LibPQ.Result ys)

327330 manipulateParams manipulation params = lift $

328331 manipulateParams manipulation params

329332

330− manipulate :: Manipulation ('[] :=> schemas) '[] ys -> pq (K LibPQ.Result ys)

333+ manipulateParams_

334+ :: (ToParams x params, All OidOfParam params)

335+ => Manipulation '[] schemas params '[]

336+ -- ^ `insertInto`, `update` or `deleteFrom`

337+ -> x -> pq ()

338+ manipulateParams_ q x = void $ manipulateParams q x

339+

340+ manipulate :: Manipulation '[] schemas '[] ys -> pq (K LibPQ.Result ys)

331341 manipulate statement = manipulateParams statement ()

332342

343+ manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()

344+ manipulate_ = void . manipulate

345+

333346 runQueryParams

334− :: ToParams x params

335− => Query ('[] :=> schemas) params ys

347+ :: (ToParams x params, All OidOfParam params)

348+ => Query '[] '[] schemas params ys

336349 -- ^ `select` and friends

337350 -> x -> pq (K LibPQ.Result ys)

338351 runQueryParams = manipulateParams . queryStatement

339352

340353 runQuery

341− :: Query ('[] :=> schemas) '[] ys

354+ :: Query '[] '[] schemas '[] ys

342355 -- ^ `select` and friends

343356 -> pq (K LibPQ.Result ys)

344357 runQuery q = runQueryParams q ()

345358

346359 traversePrepared

347− :: (ToParams x params, Traversable list)

348− => Manipulation ('[] :=> schemas) params ys

349− -- ^ `insertRows`, `update`, or `deleteFrom`, and friends

360+ :: (ToParams x params, Traversable list, All OidOfParam params)

361+ => Manipulation '[] schemas params ys

362+ -- ^ `insertInto`, `update`, or `deleteFrom`, and friends

350363 -> list x -> pq (list (K LibPQ.Result ys))

351364 default traversePrepared

352365 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

353− => (ToParams x params, Traversable list)

354− => Manipulation ('[] :=> schemas) params ys -> list x -> pq (list (K LibPQ.Result ys))

366+ => (ToParams x params, Traversable list, All OidOfParam params)

367+ => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))

355368 traversePrepared manipulation params = lift $

356369 traversePrepared manipulation params

357370

358371 forPrepared

359− :: (ToParams x params, Traversable list)

372+ :: (ToParams x params, Traversable list, All OidOfParam params)

360373 => list x

361− -> Manipulation ('[] :=> schemas) params ys

362− -- ^ `insertRows`, `update` or `deleteFrom`

374+ -> Manipulation '[] schemas params ys

375+ -- ^ `insertInto`, `update` or `deleteFrom`

363376 -> pq (list (K LibPQ.Result ys))

364377 forPrepared = flip traversePrepared

365378

366379 traversePrepared_

367− :: (ToParams x params, Foldable list)

368− => Manipulation ('[] :=> schemas) params '[]

369− -- ^ `insertRows`, `update` or `deleteFrom`

380+ :: (ToParams x params, Foldable list, All OidOfParam params)

381+ => Manipulation '[] schemas params '[]

382+ -- ^ `insertInto`, `update` or `deleteFrom`

370383 -> list x -> pq ()

371384 default traversePrepared_

372385 :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

373− => (ToParams x params, Foldable list)

374− => Manipulation ('[] :=> schemas) params '[]

375− -- ^ `insertRows`, `update` or `deleteFrom`

386+ => (ToParams x params, Foldable list, All OidOfParam params)

387+ => Manipulation '[] schemas params '[]

388+ -- ^ `insertInto`, `update` or `deleteFrom`

376389 -> list x -> pq ()

377390 traversePrepared_ manipulation params = lift $

378391 traversePrepared_ manipulation params

379392

380393 forPrepared_

381− :: (ToParams x params, Foldable list)

394+ :: (ToParams x params, Foldable list, All OidOfParam params)

382395 => list x

383− -> Manipulation ('[] :=> schemas) params '[]

384− -- ^ `insertRows`, `update` or `deleteFrom`

396+ -> Manipulation '[] schemas params '[]

397+ -- ^ `insertInto`, `update` or `deleteFrom`

385398 -> pq ()

386399 forPrepared_ = flip traversePrepared_

387400

@@ -391,61 +404,83 @@ class Monad pq => MonadPQ schemas pq | pq -> schemas where

391404 => (LibPQ.Connection -> IO a) -> pq a

392405 liftPQ = lift . liftPQ

393406

394−instance (MonadBase IO io, schemas0 ~ schemas, schemas1 ~ schemas)

407+instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)

395408 => MonadPQ schemas (PQ schemas0 schemas1 io) where

396409

397410 manipulateParams

398− (UnsafeManipulation q :: Manipulation ('[] :=> schemas) ps ys) (params :: x) =

411+ (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =

399412 PQ $ \ (K conn) -> do

400413 let

401− toParam' encoding =

402− (LibPQ.invalidOid, encodingBytes encoding, LibPQ.Binary)

403− params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))

414+ paramSet

415+ :: forall param. OidOfParam param

416+ => K (Maybe Encoding.Encoding) param

417+ -> K (Maybe (LibPQ.Oid, ByteString, LibPQ.Format)) param

418+ paramSet (K maybeEncoding) = K $

419+ maybeEncoding <&> \encoding ->

420+ (oidOfParam @param, encodingBytes encoding, LibPQ.Binary)

421+ params'

422+ = hcollapse

423+ . hcmap (Proxy @OidOfParam) paramSet

424+ $ toParams @x @ps params

404425 q' = q <> ";"

405− resultMaybe <- liftBase $ LibPQ.execParams conn q' params' LibPQ.Binary

426+ resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary

406427 case resultMaybe of

407428 Nothing -> throw $ ResultException

408429 "manipulateParams: LibPQ.execParams returned no results"

409430 Just result -> do

410− tryResult result

431+ okResult_ result

411432 return $ K (K result)

412433

413434 traversePrepared

414− (UnsafeManipulation q :: Manipulation ('[] :=> schemas) xs ys) (list :: list x) =

415− PQ $ \ (K conn) -> liftBase $ do

416− let temp = "temporary_statement"

417− prepResultMaybe <- LibPQ.prepare conn temp q Nothing

435+ (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =

436+ PQ $ \ (K conn) -> liftIO $ do

437+ let

438+ temp = "temporary_statement"

439+ paramOid :: forall p. OidOfParam p => K LibPQ.Oid p

440+ paramOid = K (oidOfParam @p)

441+ paramOids :: NP (K LibPQ.Oid) xs

442+ paramOids = hcpure (Proxy @OidOfParam) paramOid

443+ paramOids' :: [LibPQ.Oid]

444+ paramOids' = hcollapse paramOids

445+ prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')

418446 case prepResultMaybe of

419447 Nothing -> throw $ ResultException

420448 "traversePrepared: LibPQ.prepare returned no results"

421− Just prepResult -> tryResult prepResult

449+ Just prepResult -> okResult_ prepResult

422450 results <- for list $ \ params -> do

423451 let

424− toParam' encoding = (encodingBytes encoding,LibPQ.Binary)

452+ toParam' encoding = (encodingBytes encoding, LibPQ.Binary)

425453 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))

426454 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary

427455 case resultMaybe of

428456 Nothing -> throw $ ResultException

429457 "traversePrepared: LibPQ.execParams returned no results"

430458 Just result -> do

431− tryResult result

459+ okResult_ result

432460 return $ K result

433461 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

434462 case deallocResultMaybe of

435463 Nothing -> throw $ ResultException

436464 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

437− Just deallocResult -> tryResult deallocResult

465+ Just deallocResult -> okResult_ deallocResult

438466 return (K results)

439467

440468 traversePrepared_

441− (UnsafeManipulation q :: Manipulation ('[] :=> schemas) xs '[]) (list :: list x) =

442− PQ $ \ (K conn) -> liftBase $ do

443− let temp = "temporary_statement"

444− prepResultMaybe <- LibPQ.prepare conn temp q Nothing

469+ (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =

470+ PQ $ \ (K conn) -> liftIO $ do

471+ let

472+ temp = "temporary_statement"

473+ paramOid :: forall p. OidOfParam p => K LibPQ.Oid p

474+ paramOid = K (oidOfParam @p)

475+ paramOids :: NP (K LibPQ.Oid) xs

476+ paramOids = hcpure (Proxy @OidOfParam) paramOid

477+ paramOids' :: [LibPQ.Oid]

478+ paramOids' = hcollapse paramOids

479+ prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')

445480 case prepResultMaybe of

446481 Nothing -> throw $ ResultException

447482 "traversePrepared_: LibPQ.prepare returned no results"

448− Just prepResult -> tryResult prepResult

483+ Just prepResult -> okResult_ prepResult

449484 for_ list $ \ params -> do

450485 let

451486 toParam' encoding = (encodingBytes encoding, LibPQ.Binary)

@@ -454,16 +489,16 @@ instance (MonadBase IO io, schemas0 ~ schemas, schemas1 ~ schemas)

454489 case resultMaybe of

455490 Nothing -> throw $ ResultException

456491 "traversePrepared_: LibPQ.execParams returned no results"

457− Just result -> tryResult result

492+ Just result -> okResult_ result

458493 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

459494 case deallocResultMaybe of

460495 Nothing -> throw $ ResultException

461496 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

462− Just deallocResult -> tryResult deallocResult

497+ Just deallocResult -> okResult_ deallocResult

463498 return (K ())

464499

465500 liftPQ pq = PQ $ \ (K conn) -> do

466− y <- liftBase $ pq conn

501+ y <- liftIO $ pq conn

467502 return (K y)

468503

469504instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)

@@ -488,6 +523,10 @@ instance (Monad m, schemas0 ~ schemas1)

488523 return = pure

489524 (>>=) = flip pqBind

490525

526+instance (Monad m, schemas0 ~ schemas1)

527+ => Fail.MonadFail (PQ schemas0 schemas1 m) where

528+ fail = Fail.fail

529+

491530instance schemas0 ~ schemas1 => MFunctor (PQ schemas0 schemas1) where

492531 hoist f (PQ pq) = PQ (f . pq)

493532

@@ -500,36 +539,29 @@ instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where

500539 embed f (PQ pq) = PQ $ \ conn -> do

501540 evalPQ (f (pq conn)) conn

502541

503−instance (MonadBase b m, schemas0 ~ schemas1)

504− => MonadBase b (PQ schemas0 schemas1 m) where

505− liftBase = lift . liftBase

506−

507−-- | A snapshot of the state of a `PQ` computation.

508−type PQRun schemas =

509− forall m x. Monad m => PQ schemas schemas m x -> m (K x schemas)

542+instance (MonadIO m, schema0 ~ schema1)

543+ => MonadIO (PQ schema0 schema1 m) where

544+ liftIO = lift . liftIO

510545

511−-- | Helper function in defining `MonadBaseControl` instance for `PQ`.

512−pqliftWith :: Functor m => (PQRun schemas -> m a) -> PQ schemas schemas m a

513−pqliftWith f = PQ $ \ conn ->

514− fmap K (f $ \ pq -> unPQ pq conn)

515−

516−instance (MonadBaseControl b m, schemas0 ~ schemas1)

517− => MonadBaseControl b (PQ schemas0 schemas1 m) where

518− type StM (PQ schemas0 schemas1 m) x = StM m (K x schemas0)

519− liftBaseWith f =

520− pqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

521− restoreM = PQ . const . restoreM

546+instance (MonadUnliftIO m, schemas0 ~ schemas1)

547+ => MonadUnliftIO (PQ schemas0 schemas1 m) where

548+ withRunInIO

549+ :: ((forall a . PQ schemas0 schema1 m a -> IO a) -> IO b)

550+ -> PQ schemas0 schema1 m b

551+ withRunInIO inner = PQ $ \conn ->

552+ withRunInIO $ \(run :: (forall x . m x -> IO x)) ->

553+ K <$> inner (\pq -> run $ unK <$> unPQ pq conn)

522554

523555-- | Get a row corresponding to a given row number from a `LibPQ.Result`,

524556-- throwing an exception if the row number is out of bounds.

525557getRow

526− :: (FromRow columns y, MonadBase IO io)

558+ :: (FromRow columns y, MonadIO io)

527559 => LibPQ.Row

528560 -- ^ row number

529561 -> K LibPQ.Result columns

530562 -- ^ result

531563 -> io y

532−getRow r (K result :: K LibPQ.Result columns) = liftBase $ do

564+getRow r (K result :: K LibPQ.Result columns) = liftIO $ do

533565 numRows <- LibPQ.ntuples result

534566 when (numRows < r) $ throw $ ResultException $

535567 "getRow: expected at least " <> pack (show r) <> "rows but only saw "

@@ -547,13 +579,13 @@ getRow r (K result :: K LibPQ.Result columns) = liftBase $ do

547579-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,

548580-- otherwise returning the row along with the next row number.

549581nextRow

550− :: (FromRow columns y, MonadBase IO io)

582+ :: (FromRow columns y, MonadIO io)

551583 => LibPQ.Row -- ^ total number of rows

552584 -> K LibPQ.Result columns -- ^ result

553585 -> LibPQ.Row -- ^ row number

554586 -> io (Maybe (LibPQ.Row,y))

555587nextRow total (K result :: K LibPQ.Result columns) r

556− = liftBase $ if r >= total then return Nothing else do

588+ = liftIO $ if r >= total then return Nothing else do

557589 let len = fromIntegral (lengthSList (Proxy @columns))

558590 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

559591 case fromList row' of

@@ -564,10 +596,10 @@ nextRow total (K result :: K LibPQ.Result columns) r

564596

565597-- | Get all rows from a `LibPQ.Result`.

566598getRows

567− :: (FromRow columns y, MonadBase IO io)

599+ :: (FromRow columns y, MonadIO io)

568600 => K LibPQ.Result columns -- ^ result

569601 -> io [y]

570−getRows (K result :: K LibPQ.Result columns) = liftBase $ do

602+getRows (K result :: K LibPQ.Result columns) = liftIO $ do

571603 let len = fromIntegral (lengthSList (Proxy @columns))

572604 numRows <- LibPQ.ntuples result

573605 for [0 .. numRows - 1] $ \ r -> do

@@ -580,10 +612,10 @@ getRows (K result :: K LibPQ.Result columns) = liftBase $ do

580612

581613-- | Get the first row if possible from a `LibPQ.Result`.

582614firstRow

583− :: (FromRow columns y, MonadBase IO io)

615+ :: (FromRow columns y, MonadIO io)

584616 => K LibPQ.Result columns -- ^ result

585617 -> io (Maybe y)

586−firstRow (K result :: K LibPQ.Result columns) = liftBase $ do

618+firstRow (K result :: K LibPQ.Result columns) = liftIO $ do

587619 numRows <- LibPQ.ntuples result

588620 if numRows <= 0 then return Nothing else do

589621 let len = fromIntegral (lengthSList (Proxy @columns))

@@ -596,23 +628,23 @@ firstRow (K result :: K LibPQ.Result columns) = liftBase $ do

596628

597629-- | Lifts actions on results from @LibPQ@.

598630liftResult

599− :: MonadBase IO io

631+ :: MonadIO io

600632 => (LibPQ.Result -> IO x)

601633 -> K LibPQ.Result results -> io x

602−liftResult f (K result) = liftBase $ f result

634+liftResult f (K result) = liftIO $ f result

603635

604636-- | Returns the number of rows (tuples) in the query result.

605−ntuples :: MonadBase IO io => K LibPQ.Result columns -> io LibPQ.Row

637+ntuples :: MonadIO io => K LibPQ.Result columns -> io LibPQ.Row

606638ntuples = liftResult LibPQ.ntuples

607639

608640-- | Returns the result status of the command.

609−resultStatus :: MonadBase IO io => K LibPQ.Result results -> io LibPQ.ExecStatus

641+resultStatus :: MonadIO io => K LibPQ.Result results -> io LibPQ.ExecStatus

610642resultStatus = liftResult LibPQ.resultStatus

611643

612644-- | Returns the error message most recently generated by an operation

613645-- on the connection.

614646resultErrorMessage

615− :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)

647+ :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)

616648resultErrorMessage = liftResult LibPQ.resultErrorMessage

617649

618650-- | Returns the error code most recently generated by an operation

@@ -620,29 +652,29 @@ resultErrorMessage = liftResult LibPQ.resultErrorMessage

620652--

621653-- https://www.postgresql.org/docs/current/static/errcodes-appendix.html

622654resultErrorCode

623− :: MonadBase IO io

655+ :: MonadIO io

624656 => K LibPQ.Result results

625657 -> io (Maybe ByteString)

626658resultErrorCode = liftResult (flip LibPQ.resultErrorField LibPQ.DiagSqlstate)

627659

628−-- | `Exception`s that can be thrown by Squeal.

629−data SquealException

630− = PQException

660+-- | the state of LibPQ

661+data PQState = PQState

631662 { sqlExecStatus :: LibPQ.ExecStatus

632663 , sqlStateCode :: Maybe ByteString

633664 -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html

634665 , sqlErrorMessage :: Maybe ByteString

635− }

666+ } deriving (Eq, Show)

667+

668+-- | `Exception`s that can be thrown by Squeal.

669+data SquealException

670+ = PQException PQState

636671 | ResultException Text

637672 | ParseException Text

638673 deriving (Eq, Show)

639674instance Exception SquealException

640675

641−tryResult

642− :: MonadBase IO io

643− => LibPQ.Result

644− -> io ()

645−tryResult result = liftBase $ do

676+okResult_ :: MonadIO io => LibPQ.Result -> io ()

677+okResult_ result = liftIO $ do

646678 status <- LibPQ.resultStatus result

647679 case status of

648680 LibPQ.CommandOk -> return ()

@@ -650,11 +682,16 @@ tryResult result = liftBase $ do

650682 _ -> do

651683 stateCode <- LibPQ.resultErrorField result LibPQ.DiagSqlstate

652684 msg <- LibPQ.resultErrorMessage result

653− throw $ PQException status stateCode msg

685+ throw . PQException $ PQState status stateCode msg

686+

687+-- | Check if a `LibPQ.Result`'s status is either `LibPQ.CommandOk`

688+-- or `LibPQ.TuplesOk` otherwise `throw` a `PQException`.

689+okResult :: MonadIO io => K LibPQ.Result row -> io ()

690+okResult = okResult_ . unK

654691

655692-- | Catch `SquealException`s.

656693catchSqueal

657− :: MonadBaseControl IO io

694+ :: MonadUnliftIO io

658695 => io a

659696 -> (SquealException -> io a) -- ^ handler

660697 -> io a

@@ -662,7 +699,14 @@ catchSqueal = catch

662699

663700-- | Handle `SquealException`s.

664701handleSqueal

665− :: MonadBaseControl IO io

702+ :: MonadUnliftIO io

666703 => (SquealException -> io a) -- ^ handler

667704 -> io a -> io a

668705handleSqueal = handle

706+

707+-- | `Either` return a `SquealException` or a result.

708+trySqueal

709+ :: MonadUnliftIO io

710+ => io a

711+ -> io (Either SquealException a)

712+trySqueal = try

squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+72−103

@@ -1,17 +1,40 @@

11{-|

2−Module: Squeal.PostgreSQL.Definition

3−Description: Pooled connections

2+Module: Squeal.PostgreSQL.Pool

3+Description: Connection pools

44Copyright: (c) Eitan Chatav, 2017

55Maintainer: eitan@morphism.tech

66Stability: experimental

8−A `MonadPQ` for pooled connections.

8+Connection pools.

10+Typical use case would be to create your pool using `createConnectionPool`

11+and run anything that requires the pool connection with `usingConnectionPool`.

12+

13+Here's a simplified example:

14+

15+>>> import Squeal.PostgreSQL

16+

17+>>> :{

18+do

19+ let

20+ query :: Query_ (Public '[]) () (Only Char)

21+ query = values_ (literal 'a' `as` #fromOnly)

22+ pool <- createConnectionPool "host=localhost port=5432 dbname=exampledb" 1 0.5 10

23+ chr <- usingConnectionPool pool $ do

24+ result <- runQuery query

25+ Just (Only a) <- firstRow result

26+ return a

27+ destroyConnectionPool pool

28+ putChar chr

29+:}

30+a

931-}

1032

1133{-# LANGUAGE

1234 DeriveFunctor

1335 , FlexibleContexts

1436 , FlexibleInstances

37+ , InstanceSigs

1538 , MultiParamTypeClasses

1639 , RankNTypes

1740 , ScopedTypeVariables

@@ -22,55 +45,24 @@ A `MonadPQ` for pooled connections.

2245

2346module Squeal.PostgreSQL.Pool

2447 ( -- * Pools

25− PoolPQ (..)

48+ Pool

2649 , createConnectionPool

27− , Pool

28− , destroyAllResources

29− , PoolPQRun

30− , poolpqliftWith

50+ , usingConnectionPool

51+ , destroyConnectionPool

3152 ) where

3253

33−import Control.Monad.Base

34−import Control.Monad.Trans

35−import Control.Monad.Trans.Control

3654import Data.ByteString

37−import Data.Pool

3855import Data.Time

39−import Generics.SOP (K(..))

56+import Generics.SOP (K(..), unK)

57+import UnliftIO (MonadUnliftIO (..))

58+import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)

4059

4160import Squeal.PostgreSQL.PQ

42−import Squeal.PostgreSQL.Schema

43−

44−{- | `PoolPQ` @schemas@ should be a drop-in replacement for `PQ` @schemas schemas@.

45−

46−Typical use case would be to create your pool using `createConnectionPool` and run anything that requires the pool connection with it.

47−

48−Here's a simplified example:

49−

50−> type Schema = '[ "tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint2])]

51−>

52−> someQuery :: Manipulation Schema '[ 'NotNull 'PGint2] '[]

53−> someQuery = insertRow #tab

54−> (Set (param @1) `As` #col :* Nil)

55−> OnConflictDoNothing (Returning Nil)

56−>

57−> insertOne :: (MonadBaseControl IO m, MonadPQ Schema m) => m ()

58−> insertOne = void $ manipulateParams someQuery . Only $ (1 :: Int16)

59−>

60−> insertOneInPool :: ByteString -> IO ()

61−> insertOneInPool connectionString = do

62−> pool <- createConnectionPool connectionString 1 0.5 10

63−> liftIO $ runPoolPQ (insertOne) pool

64−

65−-}

66−newtype PoolPQ (schemas :: SchemasType) m x =

67− PoolPQ { runPoolPQ :: Pool (K Connection schemas) -> m x }

68− deriving Functor

6961

7062-- | Create a striped pool of connections.

7163-- 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.

7264createConnectionPool

73− :: MonadBase IO io

65+ :: MonadUnliftIO io

7466 => ByteString

7567 -- ^ The passed string can be empty to use all default parameters, or it can

7668 -- contain one or more parameter settings separated by whitespace.

@@ -87,67 +79,44 @@ createConnectionPool

8779 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.

8880 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.

8981 -> io (Pool (K Connection schemas))

90−createConnectionPool conninfo stripes idle maxResrc = liftBase $

82+createConnectionPool conninfo stripes idle maxResrc =

9183 createPool (connectdb conninfo) finish stripes idle maxResrc

9284

93−-- | `Applicative` instance for `PoolPQ`.

94−instance Monad m => Applicative (PoolPQ schemas m) where

95− pure x = PoolPQ $ \ _ -> pure x

96− PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do

97− f' <- f pool

98− x' <- x pool

99− return $ f' x'

100−

101−-- | `Monad` instance for `PoolPQ`.

102−instance Monad m => Monad (PoolPQ schemas m) where

103− return = pure

104− PoolPQ x >>= f = PoolPQ $ \ pool -> do

105− x' <- x pool

106− runPoolPQ (f x') pool

107−

108−-- | `MonadTrans` instance for `PoolPQ`.

109−instance MonadTrans (PoolPQ schemas) where

110− lift m = PoolPQ $ \ _pool -> m

111−

112−-- | `MonadBase` instance for `PoolPQ`.

113−instance MonadBase b m => MonadBase b (PoolPQ schemas m) where

114− liftBase = lift . liftBase

115−

116−-- | `MonadPQ` instance for `PoolPQ`.

117−instance MonadBaseControl IO io => MonadPQ schemas (PoolPQ schemas io) where

118− manipulateParams manipulation params = PoolPQ $ \ pool -> do

119− withResource pool $ \ conn -> do

120− (K result :: K (K Result ys) schemas) <- flip unPQ conn $

121− manipulateParams manipulation params

122− return result

123− traversePrepared manipulation params = PoolPQ $ \ pool ->

124− withResource pool $ \ conn -> do

125− (K result :: K (list (K Result ys)) schemas) <- flip unPQ conn $

126− traversePrepared manipulation params

127− return result

128− traversePrepared_ manipulation params = PoolPQ $ \ pool -> do

129− withResource pool $ \ conn -> do

130− (_ :: K () schemas) <- flip unPQ conn $

131− traversePrepared_ manipulation params

132− return ()

133− liftPQ m = PoolPQ $ \ pool ->

134− withResource pool $ \ conn -> do

135− (K result :: K result schemas) <- flip unPQ conn $

136− liftPQ m

137− return result

138−

139−-- | A snapshot of the state of a `PoolPQ` computation.

140−type PoolPQRun schemas =

141− forall m x. Monad m => PoolPQ schemas m x -> m x

142−

143−-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.

144−poolpqliftWith :: Functor m => (PoolPQRun schemas -> m a) -> PoolPQ schemas 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 schemas m) where

150− type StM (PoolPQ schemas m) x = StM m x

151− liftBaseWith f =

152− poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

153− restoreM = PoolPQ . const . restoreM

85+{-|

86+Temporarily take a connection from a `Pool`, perform an action with it,

87+and return it to the pool afterwards.

88+

89+If the pool has an idle connection available, it is used immediately.

90+Otherwise, if the maximum number of connections has not yet been reached,

91+a new connection is created and used.

92+If the maximum number of connections has been reached, this function blocks

93+until a connection becomes available.

94+-}

95+usingConnectionPool

96+ :: MonadUnliftIO io

97+ => Pool (K Connection schemas) -- ^ pool

98+ -> PQ schemas schemas io x -- ^ session

99+ -> io x

100+usingConnectionPool pool (PQ session) = unK <$> withResource pool session

101+

102+{- |

103+Destroy all connections in all stripes in the pool.

104+Note that this will ignore any exceptions in the destroy function.

105+

106+This function is useful when you detect that all connections

107+in the pool are broken. For example after a database has been

108+restarted all connections opened before the restart will be broken.

109+In that case it's better to close those connections so that

110+`usingConnectionPool` won't take a broken connection from the pool

111+but will open a new connection instead.

112+

113+Another use-case for this function is that when you know you are done

114+with the pool you can destroy all idle connections immediately

115+instead of waiting on the garbage collector to destroy them,

116+thus freeing up those connections sooner.

117+-}

118+destroyConnectionPool

119+ :: MonadUnliftIO io

120+ => Pool (K Connection schemas) -- ^ pool

121+ -> io ()

122+destroyConnectionPool = destroyAllResources

squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+558−855

@@ -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 +32,16 @@ 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+ , selectDistinctOn

43+ , selectDistinctOn_

44+ , Selection (..)

3945 -- ** Values

4046 , values

4147 , values_

@@ -47,33 +53,15 @@ module Squeal.PostgreSQL.Query

4753 , except

4854 , exceptAll

4955 -- ** With

50− , With (with)

56+ , With (..)

5157 , 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

58+ , withRecursive

6959 -- * Table Expressions

7060 , TableExpression (..)

71− , renderTableExpression

7261 , from

7362 , where_

7463 , groupBy

7564 , having

76− , orderBy

7765 , limit

7866 , offset

7967 -- * From Clauses

@@ -88,46 +76,14 @@ module Squeal.PostgreSQL.Query

8876 , rightOuterJoin

8977 , fullOuterJoin

9078 -- * Grouping

91− , By (By1, By2)

92− , renderBy

93− , GroupByClause (NoGroups, Group)

94− , renderGroupByClause

95− , HavingClause (NoHaving, Having)

96− , renderHavingClause

97− -- * Sorting

98− , SortExpression (..)

99− , renderSortExpression

100− -- * Subquery Expressions

101− , in_

102− , rowIn

103− , eqAll

104− , rowEqAll

105− , eqAny

106− , rowEqAny

107− , neqAll

108− , rowNeqAll

109− , neqAny

110− , rowNeqAny

111− , allLt

112− , rowLtAll

113− , ltAny

114− , rowLtAny

115− , lteAll

116− , rowLteAll

117− , lteAny

118− , rowLteAny

119− , gtAll

120− , rowGtAll

121− , gtAny

122− , rowGtAny

123− , gteAll

124− , rowGteAll

125− , gteAny

126− , rowGteAny

79+ , By (..)

80+ , GroupByClause (..)

81+ , HavingClause (..)

12782 ) where

12883

12984import Control.DeepSeq

13085import Data.ByteString (ByteString)

86+import Data.Kind (Type)

13187import Data.String

13288import Data.Word

13389import Generics.SOP hiding (from)

@@ -135,13 +91,67 @@ import GHC.TypeLits

13591

13692import qualified GHC.Generics as GHC

13793

94+import Squeal.PostgreSQL.Alias

13895import Squeal.PostgreSQL.Expression

96+import Squeal.PostgreSQL.Expression.Logic

97+import Squeal.PostgreSQL.Expression.Sort

98+import Squeal.PostgreSQL.Expression.Window

99+import Squeal.PostgreSQL.List

100+import Squeal.PostgreSQL.PG

139101import Squeal.PostgreSQL.Render

140102import Squeal.PostgreSQL.Schema

141103

104+-- $setup

105+-- >>> import Squeal.PostgreSQL

106+-- >>> import Data.Int (Int32, Int64)

107+-- >>> import Data.Monoid (Sum (..))

108+-- >>> import Data.Text (Text)

109+-- >>> import qualified Generics.SOP as SOP

110+

142111{- |

143−The process of retrieving or the command to retrieve data from a database

144−is called a `Query`. Let's see some examples of queries.

112+The process of retrieving or the command to retrieve data from

113+a database is called a `Query`.

114+

115+The general `Query` type is parameterized by

116+

117+* @outer :: FromType@ - outer scope for a correlated subquery,

118+* @commons :: FromType@ - scope for all `common` table expressions,

119+* @schemas :: SchemasType@ - scope for all `table`s and `view`s,

120+* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,

121+* @row :: RowType@ - return type of the `Query`.

122+-}

123+newtype Query

124+ (outer :: FromType)

125+ (commons :: FromType)

126+ (schemas :: SchemasType)

127+ (params :: [NullityType])

128+ (row :: RowType)

129+ = UnsafeQuery { renderQuery :: ByteString }

130+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

131+instance RenderSQL (Query outer commons schemas params row) where renderSQL = renderQuery

132+

133+{- |

134+The top level `Query_` type is parameterized by a @schemas@ `SchemasType`,

135+against which the query is type-checked, an input @parameters@ Haskell `Type`,

136+and an ouput row Haskell `Type`.

137+

138+A top-level query can be run

139+using `Squeal.PostgreSQL.PQ.runQueryParams`, or if @parameters = ()@

140+using `Squeal.PostgreSQL.PQ.runQuery`.

141+

142+Generally, @parameters@ will be a Haskell tuple or record whose entries

143+may be referenced using positional

144+`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a

145+Haskell record, whose entries will be targeted using overloaded labels.

146+

147+Let's see some examples of queries.

148+

149+>>> :set -XDeriveAnyClass -XDerivingStrategies

150+>>> :{

151+data Row a b = Row { col1 :: a, col2 :: b }

152+ deriving stock (GHC.Generic)

153+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

154+:}

145155

146156simple query:

147157

@@ -149,8 +159,8 @@ simple query:

149159>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

150160>>> :{

151161let

152− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

153− query = selectStar (from (table #tab))

162+ query :: Query_ (Public Schema) () (Row Int32 Int32)

163+ query = select Star (from (table #tab))

154164in printSQL query

155165:}

156166SELECT * FROM "tab" AS "tab"

@@ -159,22 +169,22 @@ restricted query:

159169

160170>>> :{

161171let

162− query :: Query (DBof (Public Schema)) '[] '["sum" ::: 'NotNull 'PGint4, "col1" ::: 'NotNull 'PGint4]

172+ query :: Query_ (Public Schema) () (Row Int32 Int32)

163173 query =

164− select ((#col1 + #col2) `as` #sum :* #col1)

174+ select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)

165175 ( from (table #tab)

166176 & where_ (#col1 .> #col2)

167177 & where_ (#col2 .> 0) )

168178in printSQL query

169179:}

170−SELECT ("col1" + "col2") AS "sum", "col1" AS "col1" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))

180+SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))

171181

172182subquery:

173183

174184>>> :{

175185let

176− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

177− query = selectStar (from (subquery (selectStar (from (table #tab)) `as` #sub)))

186+ query :: Query_ (Public Schema) () (Row Int32 Int32)

187+ query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))

178188in printSQL query

179189:}

180190SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"

@@ -183,8 +193,8 @@ limits and offsets:

183193

184194>>> :{

185195let

186− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

187− query = selectStar (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)

196+ query :: Query_ (Public Schema) () (Row Int32 Int32)

197+ query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)

188198in printSQL query

189199:}

190200SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4

@@ -193,8 +203,8 @@ parameterized query:

193203

194204>>> :{

195205let

196− query :: Query (DBof (Public Schema)) '[ 'NotNull 'PGint4] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

197− query = selectStar (from (table #tab) & where_ (#col1 .> param @1))

206+ query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)

207+ query = select Star (from (table #tab) & where_ (#col1 .> param @1))

198208in printSQL query

199209:}

200210SELECT * FROM "tab" AS "tab" WHERE ("col1" > ($1 :: int4))

@@ -203,36 +213,34 @@ aggregation query:

203213

204214>>> :{

205215let

206− query :: Query (DBof (Public Schema)) '[] '["sum" ::: 'NotNull 'PGint4, "col1" ::: 'NotNull 'PGint4 ]

216+ query :: Query_ (Public Schema) () (Row Int64 Int32)

207217 query =

208− select (sum_ #col2 `as` #sum :* #col1)

218+ select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)

209219 ( from (table (#tab `as` #table1))

210220 & groupBy #col1

211− & having (#col1 + sum_ #col2 .> 1) )

221+ & having (sum_ (Distinct #col2) .> 1) )

212222in printSQL query

213223:}

214−SELECT sum("col2") AS "sum", "col1" AS "col1" FROM "tab" AS "table1" GROUP BY "col1" HAVING (("col1" + sum("col2")) > 1)

224+SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (sum(DISTINCT "col2") > 1)

215225

216226sorted query:

217227

218228>>> :{

219229let

220− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

221− query = selectStar (from (table #tab) & orderBy [#col1 & Asc])

230+ query :: Query_ (Public Schema) () (Row Int32 Int32)

231+ query = select Star (from (table #tab) & orderBy [#col1 & Asc])

222232in printSQL query

223233:}

224234SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC

225235

226236joins:

227237

228−>>> :set -XFlexibleContexts

229238>>> :{

230239type OrdersColumns =

231240 '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

232− , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

233− , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

234− , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4

235− ]

241+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

242+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

243+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4 ]

236244:}

237245

238246>>> :{

@@ -243,26 +251,32 @@ type OrdersConstraints =

243251:}

244252

245253>>> type NamesColumns = '["id" ::: 'NoDef :=> 'NotNull 'PGint4, "name" ::: 'NoDef :=> 'NotNull 'PGtext]

246−>>> type NamesConstraints = '["pk_customers" ::: PrimaryKey '["id"]]

254+>>> type CustomersConstraints = '["pk_customers" ::: PrimaryKey '["id"]]

255+>>> type ShippersConstraints = '["pk_shippers" ::: PrimaryKey '["id"]]

247256>>> :{

248257type OrdersSchema =

249258 '[ "orders" ::: 'Table (OrdersConstraints :=> OrdersColumns)

250− , "customers" ::: 'Table (NamesConstraints :=> NamesColumns)

251− , "shippers" ::: 'Table (NamesConstraints :=> NamesColumns) ]

259+ , "customers" ::: 'Table (CustomersConstraints :=> NamesColumns)

260+ , "shippers" ::: 'Table (ShippersConstraints :=> NamesColumns) ]

261+:}

262+

263+>>> :{

264+data Order = Order

265+ { price :: Float

266+ , customerName :: Text

267+ , shipperName :: Text

268+ } deriving GHC.Generic

269+instance SOP.Generic Order

270+instance SOP.HasDatatypeInfo Order

252271:}

253272

254273>>> :{

255274let

256− query :: Query (DBof (Public OrdersSchema))

257− '[]

258− '[ "order_price" ::: 'NotNull 'PGfloat4

259− , "customer_name" ::: 'NotNull 'PGtext

260− , "shipper_name" ::: 'NotNull 'PGtext

261− ]

262− query = select

263− ( #o ! #price `as` #order_price :*

264− #c ! #name `as` #customer_name :*

265− #s ! #name `as` #shipper_name )

275+ query :: Query_ (Public OrdersSchema) () Order

276+ query = select_

277+ ( #o ! #price `as` #price :*

278+ #c ! #name `as` #customerName :*

279+ #s ! #name `as` #shipperName )

266280 ( from (table (#orders `as` #o)

267281 & innerJoin (table (#customers `as` #c))

268282 (#o ! #customer_id .== #c ! #id)

@@ -270,14 +284,16 @@ let

270284 (#o ! #shipper_id .== #s ! #id)) )

271285in printSQL query

272286:}

273−SELECT "o"."price" AS "order_price", "c"."name" AS "customer_name", "s"."name" AS "shipper_name" FROM "orders" AS "o" INNER JOIN "customers" AS "c" ON ("o"."customer_id" = "c"."id") INNER JOIN "shippers" AS "s" ON ("o"."shipper_id" = "s"."id")

287+SELECT "o"."price" AS "price", "c"."name" AS "customerName", "s"."name" AS "shipperName" FROM "orders" AS "o" INNER JOIN "customers" AS "c" ON ("o"."customer_id" = "c"."id") INNER JOIN "shippers" AS "s" ON ("o"."shipper_id" = "s"."id")

274288

275289self-join:

276290

277291>>> :{

278292let

279− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

280− query = selectDotStar #t1 (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))

293+ query :: Query_ (Public Schema) () (Row Int32 Int32)

294+ query = select

295+ (#t1 & DotStar)

296+ (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))

281297in printSQL query

282298:}

283299SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"

@@ -286,18 +302,20 @@ value queries:

286302

287303>>> :{

288304let

289− query :: Query db '[] '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

290− query = values (1 `as` #foo :* true `as` #bar) [2 `as` #foo :* false `as` #bar]

305+ query :: Query_ schemas () (Row String Bool)

306+ query = values

307+ ("true" `as` #col1 :* true `as` #col2)

308+ ["false" `as` #col1 :* false `as` #col2]

291309in printSQL query

292310:}

293−SELECT * FROM (VALUES (1, TRUE), (2, FALSE)) AS t ("foo", "bar")

311+SELECT * FROM (VALUES (E'true', TRUE), (E'false', FALSE)) AS t ("col1", "col2")

294312

295313set operations:

296314

297315>>> :{

298316let

299− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

300− query = selectStar (from (table #tab)) `unionAll` selectStar (from (table #tab))

317+ query :: Query_ (Public Schema) () (Row Int32 Int32)

318+ query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))

301319in printSQL query

302320:}

303321(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")

@@ -306,167 +324,305 @@ with queries:

306324

307325>>> :{

308326let

309− query :: Query (DBof (Public Schema)) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]

327+ query :: Query_ (Public Schema) () (Row Int32 Int32)

310328 query = with (

311− selectStar (from (table #tab)) `as` #cte1 :>>

312− selectStar (from (common #cte1)) `as` #cte2

313− ) (selectStar (from (common #cte2)))

329+ select Star (from (table #tab)) `as` #cte1 :>>

330+ select Star (from (common #cte1)) `as` #cte2

331+ ) (select Star (from (common #cte2)))

314332in printSQL query

315333:}

316334WITH "cte1" AS (SELECT * FROM "tab" AS "tab"), "cte2" AS (SELECT * FROM "cte1" AS "cte1") SELECT * FROM "cte2" AS "cte2"

335+

336+window function queries

337+

338+>>> :{

339+let

340+ query :: Query_ (Public Schema) () (Row Int32 Int64)

341+ query = select

342+ (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))

343+ (from (table #tab))

344+in printSQL query

345+:}

346+SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "col2" FROM "tab" AS "tab"

347+

348+correlated subqueries

349+

350+>>> :{

351+let

352+ query :: Query_ (Public Schema) () (Only Int32)

353+ query =

354+ select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))

355+ & where_ (exists (

356+ select Star (from (table (#tab `as` #t2))

357+ & where_ (#t2 ! #col2 .== #t1 ! #col1)))))

358+in printSQL query

359+:}

360+SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))

361+

317362-}

318−newtype Query

319− (db :: DBType)

320− (params :: [NullityType])

321− (columns :: RowType)

322− = UnsafeQuery { renderQuery :: ByteString }

323− deriving (GHC.Generic,Show,Eq,Ord,NFData)

324−instance RenderSQL (Query db params columns) where renderSQL = renderQuery

363+type family Query_

364+ (schemas :: SchemasType)

365+ (parameters :: Type)

366+ (row :: Type) where

367+ Query_ schemas params row =

368+ Query '[] '[] schemas (TuplePG params) (RowPG row)

325369

326370-- | The results of two queries can be combined using the set operation

327371-- `union`. Duplicate rows are eliminated.

328372union

329− :: Query db params columns

330− -> Query db params columns

331− -> Query db params columns

373+ :: Query outer commons schemas params columns

374+ -> Query outer commons schemas params columns

375+ -> Query outer commons schemas params columns

332376q1 `union` q2 = UnsafeQuery $

333− parenthesized (renderQuery q1)

377+ parenthesized (renderSQL q1)

334378 <+> "UNION"

335− <+> parenthesized (renderQuery q2)

379+ <+> parenthesized (renderSQL q2)

336380

337381-- | The results of two queries can be combined using the set operation

338382-- `unionAll`, the disjoint union. Duplicate rows are retained.

339383unionAll

340− :: Query db params columns

341− -> Query db params columns

342− -> Query db params columns

384+ :: Query outer commons schemas params columns

385+ -> Query outer commons schemas params columns

386+ -> Query outer commons schemas params columns

343387q1 `unionAll` q2 = UnsafeQuery $

344− parenthesized (renderQuery q1)

388+ parenthesized (renderSQL q1)

345389 <+> "UNION" <+> "ALL"

346− <+> parenthesized (renderQuery q2)

390+ <+> parenthesized (renderSQL q2)

347391

348392-- | The results of two queries can be combined using the set operation

349393-- `intersect`, the intersection. Duplicate rows are eliminated.

350394intersect

351− :: Query db params columns

352− -> Query db params columns

353− -> Query db params columns

395+ :: Query outer commons schemas params columns

396+ -> Query outer commons schemas params columns

397+ -> Query outer commons schemas params columns

354398q1 `intersect` q2 = UnsafeQuery $

355− parenthesized (renderQuery q1)

399+ parenthesized (renderSQL q1)

356400 <+> "INTERSECT"

357− <+> parenthesized (renderQuery q2)

401+ <+> parenthesized (renderSQL q2)

358402

359403-- | The results of two queries can be combined using the set operation

360404-- `intersectAll`, the intersection. Duplicate rows are retained.

361405intersectAll

362− :: Query db params columns

363− -> Query db params columns

364− -> Query db params columns

406+ :: Query outer commons schemas params columns

407+ -> Query outer commons schemas params columns

408+ -> Query outer commons schemas params columns

365409q1 `intersectAll` q2 = UnsafeQuery $

366− parenthesized (renderQuery q1)

410+ parenthesized (renderSQL q1)

367411 <+> "INTERSECT" <+> "ALL"

368− <+> parenthesized (renderQuery q2)

412+ <+> parenthesized (renderSQL q2)

369413

370414-- | The results of two queries can be combined using the set operation

371415-- `except`, the set difference. Duplicate rows are eliminated.

372416except

373− :: Query db params columns

374− -> Query db params columns

375− -> Query db params columns

417+ :: Query outer commons schemas params columns

418+ -> Query outer commons schemas params columns

419+ -> Query outer commons schemas params columns

376420q1 `except` q2 = UnsafeQuery $

377− parenthesized (renderQuery q1)

421+ parenthesized (renderSQL q1)

378422 <+> "EXCEPT"

379− <+> parenthesized (renderQuery q2)

423+ <+> parenthesized (renderSQL q2)

380424

381425-- | The results of two queries can be combined using the set operation

382426-- `exceptAll`, the set difference. Duplicate rows are retained.

383427exceptAll

384− :: Query db params columns

385− -> Query db params columns

386− -> Query db params columns

428+ :: Query outer commons schemas params columns

429+ -> Query outer commons schemas params columns

430+ -> Query outer commons schemas params columns

387431q1 `exceptAll` q2 = UnsafeQuery $

388− parenthesized (renderQuery q1)

432+ parenthesized (renderSQL q1)

389433 <+> "EXCEPT" <+> "ALL"

390− <+> parenthesized (renderQuery q2)

434+ <+> parenthesized (renderSQL q2)

391435

392436{-----------------------------------------

393437SELECT queries

394438-----------------------------------------}

395439

440+{- | The simplest kinds of `Selection` are `Star` and `DotStar` which

441+emits all columns that a `TableExpression` produces. A select `List`

442+is a list of `Expression`s. A `Selection` could be a list of

443+`WindowFunction`s `Over` `WindowDefinition`. `Additional` `Selection`s can

444+be selected with `Also`.

445+-}

446+data Selection outer commons grp schemas params from row where

447+ Star

448+ :: HasUnique tab from row

449+ => Selection outer commons 'Ungrouped schemas params from row

450+ -- ^ `HasUnique` table in the `FromClause`

451+ DotStar

452+ :: Has tab from row

453+ => Alias tab

454+ -- ^ `Has` table with `Alias`

455+ -> Selection outer commons 'Ungrouped schemas params from row

456+ List

457+ :: SListI row

458+ => NP (Aliased (Expression outer commons grp schemas params from)) row

459+ -- ^ `NP` list of `Aliased` `Expression`s

460+ -> Selection outer commons grp schemas params from row

461+ Over

462+ :: SListI row

463+ => NP (Aliased (WindowFunction outer commons grp schemas params from)) row

464+ -- ^ `NP` list of `Aliased` `WindowFunction`s

465+ -> WindowDefinition outer commons grp schemas params from

466+ -> Selection outer commons grp schemas params from row

467+ Also

468+ :: Selection outer commons grp schemas params from right

469+ -- ^ `Additional` `Selection`

470+ -> Selection outer commons grp schemas params from left

471+ -> Selection outer commons grp schemas params from (Join left right)

472+instance Additional (Selection outer commons grp schemas params from) where

473+ also = Also

474+instance (KnownSymbol col, row ~ '[col ::: ty])

475+ => Aliasable col

476+ (Expression outer commons grp schemas params from ty)

477+ (Selection outer commons grp schemas params from row) where

478+ expr `as` col = List (expr `as` col)

479+instance (Has tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

480+ => IsQualified tab col

481+ (Selection outer commons 'Ungrouped schemas params from row1) where

482+ tab ! col = tab ! col `as` col

483+instance

484+ ( Has tab (Join outer from) row0

485+ , Has col row0 ty

486+ , row1 ~ '[col ::: ty]

487+ , GroupedBy tab col bys )

488+ => IsQualified tab col

489+ (Selection outer commons ('Grouped bys) schemas params from row1) where

490+ tab ! col = tab ! col `as` col

491+instance (HasUnique tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

492+ => IsLabel col

493+ (Selection outer commons 'Ungrouped schemas params from row1) where

494+ fromLabel = fromLabel @col `as` Alias

495+instance

496+ ( HasUnique tab (Join outer from) row0

497+ , Has col row0 ty

498+ , row1 ~ '[col ::: ty]

499+ , GroupedBy tab col bys )

500+ => IsLabel col

501+ (Selection outer commons ('Grouped bys) schemas params from row1) where

502+ fromLabel = fromLabel @col `as` Alias

503+

504+instance RenderSQL (Selection outer commons grp schemas params from row) where

505+ renderSQL = \case

506+ List list -> renderCommaSeparated (renderAliased renderSQL) list

507+ Star -> "*"

508+ DotStar tab -> renderSQL tab <> ".*"

509+ Also right left -> renderSQL left <> ", " <> renderSQL right

510+ Over winFns winDef ->

511+ let

512+ renderOver

513+ :: Aliased (WindowFunction outer commons grp schemas params from) field

514+ -> ByteString

515+ renderOver (winFn `As` col) = renderSQL winFn

516+ <+> "OVER" <+> parenthesized (renderSQL winDef)

517+ <+> "AS" <+> renderSQL col

518+ in

519+ renderCommaSeparated renderOver winFns

520+

521+instance IsString

522+ (Selection outer commons grp schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where

523+ fromString str = fromString str `as` Alias

524+

396525-- | the `TableExpression` in the `select` command constructs an intermediate

397526-- virtual table by possibly combining tables, views, eliminating rows,

398527-- grouping, etc. This table is finally passed on to processing by

399−-- the select list. The select list determines which columns of

528+-- the select list. The `Selection` determines which columns of

400529-- the intermediate table are actually output.

401530select

402− :: (SListI columns, columns ~ (col ': cols))

403− => NP (Aliased (Expression db from grouping params)) columns

404− -- ^ select list

405− -> TableExpression db params from grouping

531+ :: (SListI row, row ~ (x ': xs))

532+ => Selection outer commons grp schemas params from row

533+ -- ^ selection

534+ -> TableExpression outer commons grp schemas params from

406535 -- ^ intermediate virtual table

407− -> Query db params columns

408−select list rels = UnsafeQuery $

536+ -> Query outer commons schemas params row

537+select selection tabexpr = UnsafeQuery $

409538 "SELECT"

410− <+> renderCommaSeparated (renderAliasedAs renderExpression) list

411− <+> renderTableExpression rels

539+ <+> renderSQL selection

540+ <+> renderSQL tabexpr

541+

542+-- | Like `select` but takes an `NP` list of `Expression`s instead

543+-- of a general `Selection`.

544+select_

545+ :: (SListI row, row ~ (x ': xs))

546+ => NP (Aliased (Expression outer commons grp schemas params from)) row

547+ -- ^ select list

548+ -> TableExpression outer commons grp schemas params from

549+ -- ^ intermediate virtual table

550+ -> Query outer commons schemas params row

551+select_ = select . List

412552

413553-- | After the select list has been processed, the result table can

414554-- be subject to the elimination of duplicate rows using `selectDistinct`.

415555selectDistinct

416556 :: (SListI columns, columns ~ (col ': cols))

417− => NP (Aliased (Expression db from 'Ungrouped params)) columns

418− -- ^ select list

419− -> TableExpression db params from 'Ungrouped

557+ => Selection outer commons grp schemas params from columns

558+ -- ^ selection

559+ -> TableExpression outer commons grp schemas params from

420560 -- ^ intermediate virtual table

421− -> Query db params columns

422−selectDistinct list rels = UnsafeQuery $

561+ -> Query outer commons schemas params columns

562+selectDistinct selection tabexpr = UnsafeQuery $

423563 "SELECT DISTINCT"

424− <+> renderCommaSeparated (renderAliasedAs renderExpression) list

425− <+> renderTableExpression rels

426−

427−-- | The simplest kind of query is `selectStar` which emits all columns

428−-- that the table expression produces.

429−selectStar

430− :: HasUnique table from columns

431− => TableExpression db params from 'Ungrouped

432− -- ^ intermediate virtual table

433− -> Query db params columns

434−selectStar rels = UnsafeQuery $ "SELECT" <+> "*" <+> renderTableExpression rels

435−

436−-- | A `selectDistinctStar` emits all columns that the table expression

437−-- produces and eliminates duplicate rows.

438−selectDistinctStar

439− :: HasUnique table from columns

440− => TableExpression db params from 'Ungrouped

564+ <+> renderSQL selection

565+ <+> renderSQL tabexpr

566+

567+-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead

568+-- of a general `Selection`.

569+selectDistinct_

570+ :: (SListI columns, columns ~ (col ': cols))

571+ => NP (Aliased (Expression outer commons grp schemas params from)) columns

572+ -- ^ select list

573+ -> TableExpression outer commons grp schemas params from

441574 -- ^ intermediate virtual table

442− -> Query db params columns

443−selectDistinctStar rels = UnsafeQuery $

444− "SELECT DISTINCT" <+> "*" <+> renderTableExpression rels

445−

446−-- | When working with multiple tables, it can also be useful to ask

447−-- for all the columns of a particular table, using `selectDotStar`.

448−selectDotStar

449− :: Has table from columns

450− => Alias table

451− -- ^ particular virtual subtable

452− -> TableExpression db params from 'Ungrouped

575+ -> Query outer commons schemas params columns

576+selectDistinct_ = selectDistinct . List

577+

578+{-|

579+`selectDistinctOn` keeps only the first row of each set of rows where

580+the given expressions evaluate to equal. The DISTINCT ON expressions are

581+interpreted using the same rules as for ORDER BY. ORDER BY is used to

582+ensure that the desired row appears first.

583+

584+The DISTINCT ON expression(s) must match the leftmost ORDER BY expression(s).

585+The ORDER BY clause will normally contain additional expression(s) that

586+determine the desired precedence of rows within each DISTINCT ON group.

587+

588+In order to guarantee they match and reduce redundancy, this function

589+will prepend the The DISTINCT ON expressions to the ORDER BY clause.

590+-}

591+selectDistinctOn

592+ :: (SListI columns, columns ~ (col ': cols))

593+ => [SortExpression outer commons grp schemas params from]

594+ -- ^ DISTINCT ON expression(s) and prepended to ORDER BY clause

595+ -> Selection outer commons grp schemas params from columns

596+ -- ^ selection

597+ -> TableExpression outer commons grp schemas params from

453598 -- ^ intermediate virtual table

454− -> Query db params columns

455−selectDotStar rel tab = UnsafeQuery $

456− "SELECT" <+> renderAlias rel <> ".*" <+> renderTableExpression tab

457−

458−-- | A `selectDistinctDotStar` asks for all the columns of a particular table,

459−-- and eliminates duplicate rows.

460−selectDistinctDotStar

461− :: Has table from columns

462− => Alias table

463− -- ^ particular virtual table

464− -> TableExpression db params from 'Ungrouped

599+ -> Query outer commons schemas params columns

600+selectDistinctOn distincts selection tab = UnsafeQuery $

601+ "SELECT DISTINCT ON"

602+ <+> parenthesized (commaSeparated (renderDistinctOn <$> distincts))

603+ <+> renderSQL selection

604+ <+> renderSQL (tab {orderByClause = distincts <> orderByClause tab})

605+ where

606+ renderDistinctOn = \case

607+ Asc expression -> renderSQL expression

608+ Desc expression -> renderSQL expression

609+ AscNullsFirst expression -> renderSQL expression

610+ DescNullsFirst expression -> renderSQL expression

611+ AscNullsLast expression -> renderSQL expression

612+ DescNullsLast expression -> renderSQL expression

613+

614+-- | Like `selectDistinctOn` but takes an `NP` list of `Expression`s instead

615+-- of a general `Selection`.

616+selectDistinctOn_

617+ :: (SListI columns, columns ~ (col ': cols))

618+ => [SortExpression outer commons grp schemas params from]

619+ -- ^ distinct on and return the first row in ordering

620+ -> NP (Aliased (Expression outer commons grp schemas params from)) columns

621+ -- ^ selection

622+ -> TableExpression outer commons grp schemas params from

465623 -- ^ intermediate virtual table

466− -> Query db params columns

467−selectDistinctDotStar rel tab = UnsafeQuery $

468− "SELECT DISTINCT" <+> renderAlias rel <> ".*"

469− <+> renderTableExpression tab

624+ -> Query outer commons schemas params columns

625+selectDistinctOn_ distincts = selectDistinctOn distincts . List

470626

471627-- | `values` computes a row value or set of row values

472628-- specified by value expressions. It is most commonly used

@@ -474,16 +630,16 @@ selectDistinctDotStar rel tab = UnsafeQuery $

474630-- but it can be used on its own.

475631--

476632-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]

477−-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query db '[] Row

633+-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query outer commons schemas '[] Row

478634-- >>> printSQL query

479635-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")

480636values

481637 :: SListI cols

482− => NP (Aliased (Expression db '[] 'Ungrouped params)) cols

483− -> [NP (Aliased (Expression db '[] 'Ungrouped params)) cols]

638+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

639+ -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]

484640 -- ^ When more than one row is specified, all the rows must

485641 -- must have the same number of elements

486− -> Query db params cols

642+ -> Query outer commons schemas params cols

487643values rw rws = UnsafeQuery $ "SELECT * FROM"

488644 <+> parenthesized (

489645 "VALUES"

@@ -494,17 +650,17 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"

494650 <+> parenthesized (renderCommaSeparated renderAliasPart rw)

495651 where

496652 renderAliasPart, renderValuePart

497− :: Aliased (Expression db '[] 'Ungrouped params) ty -> ByteString

498− renderAliasPart (_ `As` name) = renderAlias name

499− renderValuePart (value `As` _) = renderExpression value

653+ :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString

654+ renderAliasPart (_ `As` name) = renderSQL name

655+ renderValuePart (value `As` _) = renderSQL value

500656

501657-- | `values_` computes a row value or set of row values

502658-- specified by value expressions.

503659values_

504660 :: SListI cols

505− => NP (Aliased (Expression db '[] 'Ungrouped params)) cols

661+ => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

506662 -- ^ one row of values

507− -> Query db params cols

663+ -> Query outer commons schemas params cols

508664values_ rw = values rw []

509665

510666{-----------------------------------------

@@ -518,15 +674,17 @@ Table Expressions

518674-- to a table on disk, a so-called base table, but more complex expressions

519675-- can be used to modify or combine base tables in various ways.

520676data TableExpression

521− (db :: DBType)

677+ (outer :: FromType)

678+ (commons :: FromType)

679+ (grp :: Grouping)

680+ (schemas :: SchemasType)

522681 (params :: [NullityType])

523682 (from :: FromType)

524− (grouping :: Grouping)

525683 = TableExpression

526− { fromClause :: FromClause db params from

684+ { fromClause :: FromClause outer commons schemas params from

527685 -- ^ A table reference that can be a table name, or a derived table such

528686 -- as a subquery, a @JOIN@ construct, or complex combinations of these.

529− , whereClause :: [Condition db from 'Ungrouped params]

687+ , whereClause :: [Condition outer commons 'Ungrouped schemas params from]

530688 -- ^ optional search coditions, combined with `.&&`. After the processing

531689 -- of the `fromClause` is done, each row of the derived virtual table

532690 -- is checked against the search condition. If the result of the

@@ -535,20 +693,20 @@ data TableExpression

535693 -- at least one column of the table generated in the `fromClause`;

536694 -- this is not required, but otherwise the WHERE clause will

537695 -- be fairly useless.

538− , groupByClause :: GroupByClause from grouping

696+ , groupByClause :: GroupByClause grp from

539697 -- ^ The `groupByClause` is used to group together those rows in a table

540698 -- that have the same values in all the columns listed. The order in which

541699 -- the columns are listed does not matter. The effect is to combine each

542700 -- set of rows having common values into one group row that represents all

543701 -- rows in the group. This is done to eliminate redundancy in the output

544702 -- and/or compute aggregates that apply to these groups.

545− , havingClause :: HavingClause db from grouping params

703+ , havingClause :: HavingClause outer commons grp schemas params from

546704 -- ^ If a table has been grouped using `groupBy`, but only certain groups

547705 -- are of interest, the `havingClause` can be used, much like a

548706 -- `whereClause`, to eliminate groups from the result. Expressions in the

549707 -- `havingClause` can refer both to grouped expressions and to ungrouped

550708 -- expressions (which necessarily involve an aggregate function).

551− , orderByClause :: [SortExpression db from grouping params]

709+ , orderByClause :: [SortExpression outer commons grp schemas params from]

552710 -- ^ The `orderByClause` is for optional sorting. When more than one

553711 -- `SortExpression` is specified, the later (right) values are used to sort

554712 -- rows that are equal according to the earlier (left) values.

@@ -558,72 +716,69 @@ data TableExpression

558716 -- will be returned (but possibly fewer, if the query itself yields

559717 -- fewer rows).

560718 , offsetClause :: [Word64]

561− -- ^ The `offsetClause` is combined with `+` to give an offset count

719+ -- ^ The `offsetClause` is combined with `Prelude.+` to give an offset count

562720 -- if nonempty. The offset count says to skip that many rows before

563721 -- beginning to return rows. The rows are skipped before the limit count

564722 -- is applied.

565− }

723+ } deriving (GHC.Generic)

566724

567725-- | Render a `TableExpression`

568−renderTableExpression

569− :: TableExpression db params from grouping

570− -> ByteString

571−renderTableExpression

572− (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

573− [ "FROM ", renderFromClause frm'

574− , renderWheres whs'

575− , renderGroupByClause grps'

576− , renderHavingClause hvs'

577− , renderOrderByClause srts'

578− , renderLimits lims'

579− , renderOffsets offs'

580− ]

581− where

582− renderWheres = \case

583− [] -> ""

584− wh:[] -> " WHERE" <+> renderExpression wh

585− wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

586− renderOrderByClause = \case

587− [] -> ""

588− srts -> " ORDER BY"

589− <+> commaSeparated (renderSortExpression <$> srts)

590− renderLimits = \case

591− [] -> ""

592− lims -> " LIMIT" <+> fromString (show (minimum lims))

593− renderOffsets = \case

594− [] -> ""

595− offs -> " OFFSET" <+> fromString (show (sum offs))

726+instance RenderSQL (TableExpression outer commons grp schemas params from) where

727+ renderSQL

728+ (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

729+ [ "FROM ", renderSQL frm'

730+ , renderWheres whs'

731+ , renderSQL grps'

732+ , renderSQL hvs'

733+ , renderOrderByClause srts'

734+ , renderLimits lims'

735+ , renderOffsets offs' ]

736+ where

737+ renderWheres = \case

738+ [] -> ""

739+ wh:[] -> " WHERE" <+> renderSQL wh

740+ wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

741+ renderOrderByClause = \case

742+ [] -> ""

743+ srts -> " ORDER BY"

744+ <+> commaSeparated (renderSQL <$> srts)

745+ renderLimits = \case

746+ [] -> ""

747+ lims -> " LIMIT" <+> fromString (show (minimum lims))

748+ renderOffsets = \case

749+ [] -> ""

750+ offs -> " OFFSET" <+> fromString (show (sum offs))

596751

597752-- | A `from` generates a `TableExpression` from a table reference that can be

598753-- a table name, or a derived table such as a subquery, a JOIN construct,

599754-- or complex combinations of these. A `from` may be transformed by `where_`,

600−-- `group`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

755+-- `groupBy`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

601756-- to match the left-to-right sequencing of their placement in SQL.

602757from

603− :: FromClause db params from -- ^ table reference

604− -> TableExpression db params from 'Ungrouped

605−from rels = TableExpression rels [] NoGroups NoHaving [] [] []

758+ :: FromClause outer commons schemas params from -- ^ table reference

759+ -> TableExpression outer commons 'Ungrouped schemas params from

760+from tab = TableExpression tab [] noGroups NoHaving [] [] []

606761

607762-- | A `where_` is an endomorphism of `TableExpression`s which adds a

608763-- search condition to the `whereClause`.

609764where_

610− :: Condition db from 'Ungrouped params -- ^ filtering condition

611− -> TableExpression db params from grouping

612− -> TableExpression db params from grouping

765+ :: Condition outer commons 'Ungrouped schemas params from -- ^ filtering condition

766+ -> TableExpression outer commons grp schemas params from

767+ -> TableExpression outer commons grp schemas params from

613768where_ wh rels = rels {whereClause = wh : whereClause rels}

614769

615770-- | A `groupBy` is a transformation of `TableExpression`s which switches

616−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform

771+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform

617772-- a "grand total" aggregation query.

618773groupBy

619774 :: SListI bys

620775 => NP (By from) bys -- ^ grouped columns

621− -> TableExpression db params from 'Ungrouped

622− -> TableExpression db params from ('Grouped bys)

776+ -> TableExpression outer commons 'Ungrouped schemas params from

777+ -> TableExpression outer commons ('Grouped bys) schemas params from

623778groupBy bys rels = TableExpression

624779 { fromClause = fromClause rels

625780 , whereClause = whereClause rels

626− , groupByClause = Group bys

781+ , groupByClause = group bys

627782 , havingClause = Having []

628783 , orderByClause = []

629784 , limitClause = limitClause rels

@@ -633,177 +788,31 @@ groupBy bys rels = TableExpression

633788-- | A `having` is an endomorphism of `TableExpression`s which adds a

634789-- search condition to the `havingClause`.

635790having

636− :: Condition db from ('Grouped bys) params -- ^ having condition

637− -> TableExpression db params from ('Grouped bys)

638− -> TableExpression db params from ('Grouped bys)

791+ :: Condition outer commons ('Grouped bys) schemas params from -- ^ having condition

792+ -> TableExpression outer commons ('Grouped bys) schemas params from

793+ -> TableExpression outer commons ('Grouped bys) schemas params from

639794having hv rels = rels

640795 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }

641796

642−-- | An `orderBy` is an endomorphism of `TableExpression`s which appends an

643−-- ordering to the right of the `orderByClause`.

644−orderBy

645− :: [SortExpression db from grouping params] -- ^ sort expressions

646− -> TableExpression db params from grouping

647− -> TableExpression db params from grouping

648−orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

797+instance OrderBy TableExpression where

798+ orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

649799

650800-- | A `limit` is an endomorphism of `TableExpression`s which adds to the

651801-- `limitClause`.

652802limit

653803 :: Word64 -- ^ limit parameter

654− -> TableExpression db params from grouping

655− -> TableExpression db params from grouping

804+ -> TableExpression outer commons grp schemas params from

805+ -> TableExpression outer commons grp schemas params from

656806limit lim rels = rels {limitClause = lim : limitClause rels}

657807

658808-- | An `offset` is an endomorphism of `TableExpression`s which adds to the

659809-- `offsetClause`.

660810offset

661811 :: Word64 -- ^ offset parameter

662− -> TableExpression db params from grouping

663− -> TableExpression db params from grouping

812+ -> TableExpression outer commons grp schemas params from

813+ -> TableExpression outer commons grp schemas params from

664814offset off rels = rels {offsetClause = off : offsetClause rels}

665815

666−{-----------------------------------------

667−JSON stuff

668−-----------------------------------------}

669−

670−unsafeSetOfFunction

671− :: ByteString

672− -> Expression db '[] 'Ungrouped params ty

673− -> Query db params row

674−unsafeSetOfFunction fun expr = UnsafeQuery $

675− "SELECT * FROM " <> fun <> "(" <> renderExpression expr <> ")"

676−

677−-- | Expands the outermost JSON object into a set of key/value pairs.

678−jsonEach

679− :: Expression db '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

680− -> Query db params

681− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

682−jsonEach = unsafeSetOfFunction "json_each"

683−

684−-- | Expands the outermost binary JSON object into a set of key/value pairs.

685−jsonbEach

686− :: Expression db '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

687− -> Query db params

688− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjsonb]

689−jsonbEach = unsafeSetOfFunction "jsonb_each"

690−

691−-- | Expands the outermost JSON object into a set of key/value pairs.

692−jsonEachAsText

693− :: Expression db '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

694− -> Query db params

695− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

696−jsonEachAsText = unsafeSetOfFunction "json_each_text"

697−

698−-- | Expands the outermost binary JSON object into a set of key/value pairs.

699−jsonbEachAsText

700− :: Expression db '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

701− -> Query db params

702− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

703−jsonbEachAsText = unsafeSetOfFunction "jsonb_each_text"

704−

705−-- | Returns set of keys in the outermost JSON object.

706−jsonObjectKeys

707− :: Expression db '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

708− -> Query db params '["json_object_keys" ::: 'NotNull 'PGtext]

709−jsonObjectKeys = unsafeSetOfFunction "json_object_keys"

710−

711−-- | Returns set of keys in the outermost JSON object.

712−jsonbObjectKeys

713− :: Expression db '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

714− -> Query db params '["jsonb_object_keys" ::: 'NotNull 'PGtext]

715−jsonbObjectKeys = unsafeSetOfFunction "jsonb_object_keys"

716−

717−unsafePopulateFunction

718− :: ByteString

719− -> TypeExpression schemas (nullity ('PGcomposite row))

720− -> Expression (commons :=> schemas) '[] 'Ungrouped params ty

721− -> Query (commons :=> schemas) params row

722−unsafePopulateFunction fun ty expr = UnsafeQuery $

723− "SELECT * FROM " <> fun <> "("

724− <> "null::" <> renderTypeExpression ty <> ", "

725− <> renderExpression expr <> ")"

726−

727−-- | Expands the JSON expression to a row whose columns match the record

728−-- type defined by the given table.

729−jsonPopulateRecord

730− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type

731− -> Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

732− -> Query (commons :=> schemas) params row

733−jsonPopulateRecord = unsafePopulateFunction "json_populate_record"

734−

735−-- | Expands the binary JSON expression to a row whose columns match the record

736−-- type defined by the given table.

737−jsonbPopulateRecord

738− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type

739− -> Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

740− -> Query (commons :=> schemas) params row

741−jsonbPopulateRecord = unsafePopulateFunction "jsonb_populate_record"

742−

743−-- | Expands the outermost array of objects in the given JSON expression to a

744−-- set of rows whose columns match the record type defined by the given table.

745−jsonPopulateRecordSet

746− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type

747− -> Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjson) -- ^ json array

748− -> Query (commons :=> schemas) params row

749−jsonPopulateRecordSet = unsafePopulateFunction "json_populate_record_set"

750−

751−-- | Expands the outermost array of objects in the given binary JSON expression

752−-- to a set of rows whose columns match the record type defined by the given

753−-- table.

754−jsonbPopulateRecordSet

755− :: TypeExpression schemas (nullity ('PGcomposite row)) -- ^ row type

756− -> Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb array

757− -> Query (commons :=> schemas) params row

758−jsonbPopulateRecordSet = unsafePopulateFunction "jsonb_populate_record_set"

759−

760−unsafeRecordFunction

761− :: (SListI record, json `In` PGJsonType)

762− => ByteString

763− -> Expression (commons :=> schemas) '[] 'Ungrouped params (nullity json)

764− -> NP (Aliased (TypeExpression schemas)) record

765− -> Query (commons :=> schemas) params record

766−unsafeRecordFunction fun expr types = UnsafeQuery $

767− "SELECT * FROM " <> fun <> "("

768− <> renderExpression expr <> ")"

769− <+> "AS" <+> "x" <> parenthesized (renderCommaSeparated renderTy types)

770− where

771− renderTy :: Aliased (TypeExpression db) ty -> ByteString

772− renderTy (ty `As` alias) =

773− renderAlias alias <+> renderTypeExpression ty

774−

775−-- | Builds an arbitrary record from a JSON object.

776−jsonToRecord

777− :: SListI record

778− => Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjson) -- ^ json object

779− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types

780− -> Query (commons :=> schemas) params record

781−jsonToRecord = unsafeRecordFunction "json_to_record"

782−

783−-- | Builds an arbitrary record from a binary JSON object.

784−jsonbToRecord

785− :: SListI record

786− => Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb object

787− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types

788− -> Query (commons :=> schemas) params record

789−jsonbToRecord = unsafeRecordFunction "jsonb_to_record"

790−

791−-- | Builds an arbitrary set of records from a JSON array of objects.

792−jsonToRecordSet

793− :: SListI record

794− => Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjson) -- ^ json array

795− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types

796− -> Query (commons :=> schemas) params record

797−jsonToRecordSet = unsafeRecordFunction "json_to_record_set"

798−

799−-- | Builds an arbitrary set of records from a binary JSON array of objects.

800−jsonbToRecordSet

801− :: SListI record

802− => Expression (commons :=> schemas) '[] 'Ungrouped params (nullity 'PGjsonb) -- ^ jsonb array

803− -> NP (Aliased (TypeExpression schemas)) record -- ^ record types

804− -> Query (commons :=> schemas) params record

805−jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"

806−

807816{-----------------------------------------

808817FROM clauses

809818-----------------------------------------}

@@ -812,68 +821,76 @@ FROM clauses

812821A `FromClause` can be a table name, or a derived table such

813822as a subquery, a @JOIN@ construct, or complex combinations of these.

814823-}

815−newtype FromClause db params from

824+newtype FromClause outer commons schemas params from

816825 = UnsafeFromClause { renderFromClause :: ByteString }

817826 deriving (GHC.Generic,Show,Eq,Ord,NFData)

827+instance RenderSQL (FromClause outer commons schemas params from) where

828+ renderSQL = renderFromClause

818829

819830-- | A real `table` is a table from the database.

820831table

821832 :: (Has sch schemas schema, Has tab schema ('Table table))

822833 => Aliased (QualifiedAlias sch) (alias ::: tab)

823− -> FromClause (commons :=> schemas) params '[alias ::: TableToRow table]

834+ -> FromClause outer commons schemas params '[alias ::: TableToRow table]

824835table (tab `As` alias) = UnsafeFromClause $

825− renderQualifiedAlias tab <+> "AS" <+> renderAlias alias

836+ renderSQL tab <+> "AS" <+> renderSQL alias

826837

827838-- | `subquery` derives a table from a `Query`.

828839subquery

829− :: Aliased (Query db params) query

830− -> FromClause db params '[query]

831−subquery = UnsafeFromClause . renderAliasedAs (parenthesized . renderQuery)

840+ :: Aliased (Query outer commons schemas params) query

841+ -> FromClause outer commons schemas params '[query]

842+subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)

832843

833844-- | `view` derives a table from a `View`.

834845view

835846 :: (Has sch schemas schema, Has vw schema ('View view))

836847 => Aliased (QualifiedAlias sch) (alias ::: vw)

837− -> FromClause (commons :=> schemas) params '[alias ::: view]

848+ -> FromClause outer commons schemas params '[alias ::: view]

838849view (vw `As` alias) = UnsafeFromClause $

839− renderQualifiedAlias vw <+> "AS" <+> renderAlias alias

850+ renderSQL vw <+> "AS" <+> renderSQL alias

840851

852+-- | `common` derives a table from a common table expression.

841853common

842854 :: Has cte commons common

843855 => Aliased Alias (alias ::: cte)

844− -> FromClause (commons :=> schemas) params '[alias ::: common]

856+ -> FromClause outer commons schemas params '[alias ::: common]

845857common (cte `As` alias) = UnsafeFromClause $

846− renderAlias cte <+> "AS" <+> renderAlias alias

858+ renderSQL cte <+> "AS" <+> renderSQL alias

847859

848−{- | @left & crossJoin right@. For every possible combination of rows from

849− @left@ and @right@ (i.e., a Cartesian product), the joined table will contain

850− a row consisting of all columns in @left@ followed by all columns in @right@.

851− If the tables have @n@ and @m@ rows respectively, the joined table will

852− have @n * m@ rows.

860+instance Additional (FromClause outer commons schemas params) where

861+ also right left = UnsafeFromClause $

862+ renderSQL left <> ", " <> renderSQL right

863+

864+{- |

865+@left & crossJoin right@. For every possible combination of rows from

866+@left@ and @right@ (i.e., a Cartesian product), the joined table will contain

867+a row consisting of all columns in @left@ followed by all columns in @right@.

868+If the tables have @n@ and @m@ rows respectively, the joined table will

869+have @n * m@ rows.

853870-}

854871crossJoin

855− :: FromClause db params right

872+ :: FromClause outer commons schemas params right

856873 -- ^ right

857− -> FromClause db params left

874+ -> FromClause outer commons schemas params left

858875 -- ^ left

859− -> FromClause db params (Join left right)

876+ -> FromClause outer commons schemas params (Join left right)

860877crossJoin right left = UnsafeFromClause $

861− renderFromClause left <+> "CROSS JOIN" <+> renderFromClause right

878+ renderSQL left <+> "CROSS JOIN" <+> renderSQL right

862879

863880{- | @left & innerJoin right on@. The joined table is filtered by

864881the @on@ condition.

865882-}

866883innerJoin

867− :: FromClause db params right

884+ :: FromClause outer commons schemas params right

868885 -- ^ right

869− -> Condition db (Join left right) 'Ungrouped params

886+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

870887 -- ^ @on@ condition

871− -> FromClause db params left

888+ -> FromClause outer commons schemas params left

872889 -- ^ left

873− -> FromClause db params (Join left right)

890+ -> FromClause outer commons schemas params (Join left right)

874891innerJoin right on left = UnsafeFromClause $

875− renderFromClause left <+> "INNER JOIN" <+> renderFromClause right

876− <+> "ON" <+> renderExpression on

892+ renderSQL left <+> "INNER JOIN" <+> renderSQL right

893+ <+> "ON" <+> renderSQL on

877894

878895{- | @left & leftOuterJoin right on@. First, an inner join is performed.

879896 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -881,16 +898,16 @@ innerJoin right on left = UnsafeFromClause $

881898 Thus, the joined table always has at least one row for each row in @left@.

882899-}

883900leftOuterJoin

884− :: FromClause db params right

901+ :: FromClause outer commons schemas params right

885902 -- ^ right

886− -> Condition db (Join left right) 'Ungrouped params

903+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

887904 -- ^ @on@ condition

888− -> FromClause db params left

905+ -> FromClause outer commons schemas params left

889906 -- ^ left

890− -> FromClause db params (Join left (NullifyFrom right))

907+ -> FromClause outer commons schemas params (Join left (NullifyFrom right))

891908leftOuterJoin right on left = UnsafeFromClause $

892− renderFromClause left <+> "LEFT OUTER JOIN" <+> renderFromClause right

893− <+> "ON" <+> renderExpression on

909+ renderSQL left <+> "LEFT OUTER JOIN" <+> renderSQL right

910+ <+> "ON" <+> renderSQL on

894911

895912{- | @left & rightOuterJoin right on@. First, an inner join is performed.

896913 Then, for each row in @right@ that does not satisfy the @on@ condition with

@@ -899,16 +916,16 @@ leftOuterJoin right on left = UnsafeFromClause $

899916 have a row for each row in @right@.

900917-}

901918rightOuterJoin

902− :: FromClause db params right

919+ :: FromClause outer commons schemas params right

903920 -- ^ right

904− -> Condition db (Join left right) 'Ungrouped params

921+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

905922 -- ^ @on@ condition

906− -> FromClause db params left

923+ -> FromClause outer commons schemas params left

907924 -- ^ left

908− -> FromClause db params (Join (NullifyFrom left) right)

925+ -> FromClause outer commons schemas params (Join (NullifyFrom left) right)

909926rightOuterJoin right on left = UnsafeFromClause $

910− renderFromClause left <+> "RIGHT OUTER JOIN" <+> renderFromClause right

911− <+> "ON" <+> renderExpression on

927+ renderSQL left <+> "RIGHT OUTER JOIN" <+> renderSQL right

928+ <+> "ON" <+> renderSQL on

912929

913930{- | @left & fullOuterJoin right on@. First, an inner join is performed.

914931 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -918,23 +935,23 @@ rightOuterJoin right on left = UnsafeFromClause $

918935 is added.

919936-}

920937fullOuterJoin

921− :: FromClause db params right

938+ :: FromClause outer commons schemas params right

922939 -- ^ right

923− -> Condition db (Join left right) 'Ungrouped params

940+ -> Condition outer commons 'Ungrouped schemas params (Join left right)

924941 -- ^ @on@ condition

925− -> FromClause db params left

942+ -> FromClause outer commons schemas params left

926943 -- ^ left

927− -> FromClause db params

944+ -> FromClause outer commons schemas params

928945 (Join (NullifyFrom left) (NullifyFrom right))

929946fullOuterJoin right on left = UnsafeFromClause $

930− renderFromClause left <+> "FULL OUTER JOIN" <+> renderFromClause right

931− <+> "ON" <+> renderExpression on

947+ renderSQL left <+> "FULL OUTER JOIN" <+> renderSQL right

948+ <+> "ON" <+> renderSQL on

932949

933950{-----------------------------------------

934951Grouping

935952-----------------------------------------}

936953

937−-- | `By`s are used in `group` to reference a list of columns which are then

954+-- | `By`s are used in `groupBy` to reference a list of columns which are then

938955-- used to group together those rows in a table that have the same values

939956-- in all the columns listed. @By \#col@ will reference an unambiguous

940957-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table

@@ -954,6 +971,10 @@ data By

954971deriving instance Show (By from by)

955972deriving instance Eq (By from by)

956973deriving instance Ord (By from by)

974+instance RenderSQL (By from by) where

975+ renderSQL = \case

976+ By1 column -> renderSQL column

977+ By2 rel column -> renderSQL rel <> "." <> renderSQL column

957978

958979instance (HasUnique rel rels cols, Has col cols ty, by ~ '(rel, col))

959980 => IsLabel col (By rels by) where fromLabel = By1 fromLabel

@@ -965,431 +986,113 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])

965986 => IsQualified rel col (NP (By rels) bys) where

966987 rel ! col = By2 rel col :* Nil

967988

968−-- | Renders a `By`.

969−renderBy :: By from by -> ByteString

970−renderBy = \case

971− By1 column -> renderAlias column

972− By2 rel column -> renderAlias rel <> "." <> renderAlias column

973−

974989-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.

975990-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.

976991-- @NoGroups@ is distinguised from @Group Nil@ since no aggregation can be

977992-- done on @NoGroups@ while all output `Expression`s must be aggregated

978993-- in @Group Nil@. In general, all output `Expression`s in the

979994-- complement of @bys@ must be aggregated in @Group bys@.

980−data GroupByClause from grouping where

981− NoGroups :: GroupByClause from 'Ungrouped

982− Group

983− :: SListI bys

984− => NP (By from) bys

985− -> GroupByClause from ('Grouped bys)

986−

987−-- | Renders a `GroupByClause`.

988−renderGroupByClause :: GroupByClause from grouping -> ByteString

989−renderGroupByClause = \case

990− NoGroups -> ""

991− Group Nil -> ""

992− Group bys -> " GROUP BY" <+> renderCommaSeparated renderBy bys

995+newtype GroupByClause grp from = UnsafeGroupByClause

996+ { renderGroupByClause :: ByteString }

997+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

998+instance RenderSQL (GroupByClause grp from) where

999+ renderSQL = renderGroupByClause

1000+noGroups :: GroupByClause 'Ungrouped from

1001+noGroups = UnsafeGroupByClause ""

1002+group

1003+ :: SListI bys

1004+ => NP (By from) bys

1005+ -> GroupByClause ('Grouped bys) from

1006+group bys = UnsafeGroupByClause $ case bys of

1007+ Nil -> ""

1008+ bys' -> " GROUP BY" <+> renderCommaSeparated renderSQL bys'

9931009

9941010-- | A `HavingClause` is used to eliminate groups that are not of interest.

9951011-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`

9961012-- `TableExpression` must use `Having` whose conditions are combined with

9971013-- `.&&`.

998−data HavingClause db from grouping params where

999− NoHaving :: HavingClause db from 'Ungrouped params

1014+data HavingClause outer commons grp schemas params from where

1015+ NoHaving :: HavingClause outer commons 'Ungrouped schemas params from

10001016 Having

1001− :: [Condition db from ('Grouped bys) params]

1002− -> HavingClause db from ('Grouped bys) params

1003−deriving instance Show (HavingClause db from grouping params)

1004−deriving instance Eq (HavingClause db from grouping params)

1005−deriving instance Ord (HavingClause db from grouping params)

1017+ :: [Condition outer commons ('Grouped bys) schemas params from]

1018+ -> HavingClause outer commons ('Grouped bys) schemas params from

1019+deriving instance Show (HavingClause outer commons grp schemas params from)

1020+deriving instance Eq (HavingClause outer commons grp schemas params from)

1021+deriving instance Ord (HavingClause outer commons grp schemas params from)

10061022

10071023-- | Render a `HavingClause`.

1008−renderHavingClause :: HavingClause db from grouping params -> ByteString

1009−renderHavingClause = \case

1010− NoHaving -> ""

1011− Having [] -> ""

1012− Having conditions ->

1013− " HAVING" <+> commaSeparated (renderExpression <$> conditions)

1014−

1015−{-----------------------------------------

1016−Sorting

1017−-----------------------------------------}

1018−

1019−-- | `SortExpression`s are used by `sortBy` to optionally sort the results

1020−-- of a `Query`. `Asc` or `Desc` set the sort direction of a `NotNull` result

1021−-- column to ascending or descending. Ascending order puts smaller values

1022−-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,

1023−-- descending order is determined with the `.>` operator. `AscNullsFirst`,

1024−-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to

1025−-- determine whether nulls appear before or after non-null values in the sort

1026−-- ordering of a `Null` result column.

1027−data SortExpression db from grouping params where

1028− Asc

1029− :: Expression db from grouping params ('NotNull ty)

1030− -> SortExpression db from grouping params

1031− Desc

1032− :: Expression db from grouping params ('NotNull ty)

1033− -> SortExpression db from grouping params

1034− AscNullsFirst

1035− :: Expression db from grouping params ('Null ty)

1036− -> SortExpression db from grouping params

1037− AscNullsLast

1038− :: Expression db from grouping params ('Null ty)

1039− -> SortExpression db from grouping params

1040− DescNullsFirst

1041− :: Expression db from grouping params ('Null ty)

1042− -> SortExpression db from grouping params

1043− DescNullsLast

1044− :: Expression db from grouping params ('Null ty)

1045− -> SortExpression db from grouping params

1046−deriving instance Show (SortExpression db from grouping params)

1047−

1048−-- | Render a `SortExpression`.

1049−renderSortExpression :: SortExpression db from grouping params -> ByteString

1050−renderSortExpression = \case

1051− Asc expression -> renderExpression expression <+> "ASC"

1052− Desc expression -> renderExpression expression <+> "DESC"

1053− AscNullsFirst expression -> renderExpression expression

1054− <+> "ASC NULLS FIRST"

1055− DescNullsFirst expression -> renderExpression expression

1056− <+> "DESC NULLS FIRST"

1057− AscNullsLast expression -> renderExpression expression <+> "ASC NULLS LAST"

1058− DescNullsLast expression -> renderExpression expression <+> "DESC NULLS LAST"

1059−

1060−unsafeSubqueryExpression

1061− :: ByteString

1062− -> Expression db from grp params ty

1063− -> Query db params '[alias ::: ty]

1064− -> Expression db from grp params (nullity 'PGbool)

1065−unsafeSubqueryExpression op x q = UnsafeExpression $

1066− renderExpression x <+> op <+> parenthesized (renderQuery q)

1067−

1068−unsafeRowSubqueryExpression

1069− :: SListI row

1070− => ByteString

1071− -> NP (Aliased (Expression db from grp params)) row

1072− -> Query db params row

1073− -> Expression db from grp params (nullity 'PGbool)

1074−unsafeRowSubqueryExpression op xs q = UnsafeExpression $

1075− renderExpression (row xs) <+> op <+> parenthesized (renderQuery q)

1076−

1077−-- | The right-hand side is a sub`Query`, which must return exactly one column.

1078−-- The left-hand expression is evaluated and compared to each row of the

1079−-- sub`Query` result. The result of `in_` is `true` if any equal subquery row is found.

1080−-- The result is `false` if no equal row is found

1081−-- (including the case where the subquery returns no rows).

1082−--

1083−-- >>> printSQL $ true `in_` values_ (true `as` #foo)

1084−-- TRUE IN (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1085−in_

1086− :: Expression db from grp params ty -- ^ expression

1087− -> Query db params '[alias ::: ty] -- ^ subquery

1088− -> Expression db from grp params (nullity 'PGbool)

1089−in_ = unsafeSubqueryExpression "IN"

1090−

1091−{- | The left-hand side of this form of `rowIn` is a row constructor.

1092−The right-hand side is a sub`Query`,

1093−which must return exactly as many columns as

1094−there are expressions in the left-hand row.

1095−The left-hand expressions are evaluated and compared row-wise to each row

1096−of the subquery result. The result of `rowIn`

1097−is `true` if any equal subquery row is found.

1098−The result is `false` if no equal row is found

1099−(including the case where the subquery returns no rows).

1100−

1101−>>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1102−>>> printSQL $ myRow `rowIn` values_ myRow

1103−ROW(1, FALSE) IN (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1104−-}

1105−rowIn

1106− :: SListI row

1107− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1108− -> Query db params row -- ^ subquery

1109− -> Expression db from grp params (nullity 'PGbool)

1110−rowIn = unsafeRowSubqueryExpression "IN"

1111−

1112−-- | >>> printSQL $ true `eqAll` values_ (true `as` #foo)

1113−-- TRUE = ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1114−eqAll

1115− :: Expression db from grp params ty -- ^ expression

1116− -> Query db params '[alias ::: ty] -- ^ subquery

1117− -> Expression db from grp params (nullity 'PGbool)

1118−eqAll = unsafeSubqueryExpression "= ALL"

1119−

1120−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1121−-- >>> printSQL $ myRow `rowEqAll` values_ myRow

1122−-- ROW(1, FALSE) = ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1123−rowEqAll

1124− :: SListI row

1125− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1126− -> Query db params row -- ^ subquery

1127− -> Expression db from grp params (nullity 'PGbool)

1128−rowEqAll = unsafeRowSubqueryExpression "= ALL"

1129−

1130−-- | >>> printSQL $ true `eqAny` values_ (true `as` #foo)

1131−-- TRUE = ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1132−eqAny

1133− :: Expression db from grp params ty -- ^ expression

1134− -> Query db params '[alias ::: ty] -- ^ subquery

1135− -> Expression db from grp params (nullity 'PGbool)

1136−eqAny = unsafeSubqueryExpression "= ANY"

1137−

1138−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1139−-- >>> printSQL $ myRow `rowEqAny` values_ myRow

1140−-- ROW(1, FALSE) = ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1141−rowEqAny

1142− :: SListI row

1143− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1144− -> Query db params row -- ^ subquery

1145− -> Expression db from grp params (nullity 'PGbool)

1146−rowEqAny = unsafeRowSubqueryExpression "= ANY"

1147−

1148−-- | >>> printSQL $ true `neqAll` values_ (true `as` #foo)

1149−-- TRUE <> ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1150−neqAll

1151− :: Expression db from grp params ty -- ^ expression

1152− -> Query db params '[alias ::: ty] -- ^ subquery

1153− -> Expression db from grp params (nullity 'PGbool)

1154−neqAll = unsafeSubqueryExpression "<> ALL"

1155−

1156−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1157−-- >>> printSQL $ myRow `rowNeqAll` values_ myRow

1158−-- ROW(1, FALSE) <> ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1159−rowNeqAll

1160− :: SListI row

1161− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1162− -> Query db params row -- ^ subquery

1163− -> Expression db from grp params (nullity 'PGbool)

1164−rowNeqAll = unsafeRowSubqueryExpression "<> ALL"

1165−

1166−-- | >>> printSQL $ true `neqAny` values_ (true `as` #foo)

1167−-- TRUE <> ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1168−neqAny

1169− :: Expression db from grp params ty -- ^ expression

1170− -> Query db params '[alias ::: ty] -- ^ subquery

1171− -> Expression db from grp params (nullity 'PGbool)

1172−neqAny = unsafeSubqueryExpression "<> ANY"

1173−

1174−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1175−-- >>> printSQL $ myRow `rowNeqAny` values_ myRow

1176−-- ROW(1, FALSE) <> ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1177−rowNeqAny

1178− :: SListI row

1179− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1180− -> Query db params row -- ^ subquery

1181− -> Expression db from grp params (nullity 'PGbool)

1182−rowNeqAny = unsafeRowSubqueryExpression "<> ANY"

1183−

1184−-- | >>> printSQL $ true `allLt` values_ (true `as` #foo)

1185−-- TRUE ALL < (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1186−allLt

1187− :: Expression db from grp params ty -- ^ expression

1188− -> Query db params '[alias ::: ty] -- ^ subquery

1189− -> Expression db from grp params (nullity 'PGbool)

1190−allLt = unsafeSubqueryExpression "ALL <"

1191−

1192−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1193−-- >>> printSQL $ myRow `rowLtAll` values_ myRow

1194−-- ROW(1, FALSE) ALL < (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1195−rowLtAll

1196− :: SListI row

1197− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1198− -> Query db params row -- ^ subquery

1199− -> Expression db from grp params (nullity 'PGbool)

1200−rowLtAll = unsafeRowSubqueryExpression "ALL <"

1201−

1202−-- | >>> printSQL $ true `ltAny` values_ (true `as` #foo)

1203−-- TRUE ANY < (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1204−ltAny

1205− :: Expression db from grp params ty -- ^ expression

1206− -> Query db params '[alias ::: ty] -- ^ subquery

1207− -> Expression db from grp params (nullity 'PGbool)

1208−ltAny = unsafeSubqueryExpression "ANY <"

1209−

1210−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1211−-- >>> printSQL $ myRow `rowLtAll` values_ myRow

1212−-- ROW(1, FALSE) ALL < (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1213−rowLtAny

1214− :: SListI row

1215− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1216− -> Query db params row -- ^ subquery

1217− -> Expression db from grp params (nullity 'PGbool)

1218−rowLtAny = unsafeRowSubqueryExpression "ANY <"

1219−

1220−-- | >>> printSQL $ true `lteAll` values_ (true `as` #foo)

1221−-- TRUE <= ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1222−lteAll

1223− :: Expression db from grp params ty -- ^ expression

1224− -> Query db params '[alias ::: ty] -- ^ subquery

1225− -> Expression db from grp params (nullity 'PGbool)

1226−lteAll = unsafeSubqueryExpression "<= ALL"

1227−

1228−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1229−-- >>> printSQL $ myRow `rowLteAll` values_ myRow

1230−-- ROW(1, FALSE) <= ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1231−rowLteAll

1232− :: SListI row

1233− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1234− -> Query db params row -- ^ subquery

1235− -> Expression db from grp params (nullity 'PGbool)

1236−rowLteAll = unsafeRowSubqueryExpression "<= ALL"

1237−

1238−-- | >>> printSQL $ true `lteAny` values_ (true `as` #foo)

1239−-- TRUE <= ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1240−lteAny

1241− :: Expression db from grp params ty -- ^ expression

1242− -> Query db params '[alias ::: ty] -- ^ subquery

1243− -> Expression db from grp params (nullity 'PGbool)

1244−lteAny = unsafeSubqueryExpression "<= ANY"

1245−

1246−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1247−-- >>> printSQL $ myRow `rowLteAny` values_ myRow

1248−-- ROW(1, FALSE) <= ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1249−rowLteAny

1250− :: SListI row

1251− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1252− -> Query db params row -- ^ subquery

1253− -> Expression db from grp params (nullity 'PGbool)

1254−rowLteAny = unsafeRowSubqueryExpression "<= ANY"

1255−

1256−-- | >>> printSQL $ true `gtAll` values_ (true `as` #foo)

1257−-- TRUE > ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1258−gtAll

1259− :: Expression db from grp params ty -- ^ expression

1260− -> Query db params '[alias ::: ty] -- ^ subquery

1261− -> Expression db from grp params (nullity 'PGbool)

1262−gtAll = unsafeSubqueryExpression "> ALL"

1263−

1264−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1265−-- >>> printSQL $ myRow `rowGtAll` values_ myRow

1266−-- ROW(1, FALSE) > ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1267−rowGtAll

1268− :: SListI row

1269− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1270− -> Query db params row -- ^ subquery

1271− -> Expression db from grp params (nullity 'PGbool)

1272−rowGtAll = unsafeRowSubqueryExpression "> ALL"

1273−

1274−-- | >>> printSQL $ true `gtAny` values_ (true `as` #foo)

1275−-- TRUE > ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1276−gtAny

1277− :: Expression db from grp params ty -- ^ expression

1278− -> Query db params '[alias ::: ty] -- ^ subquery

1279− -> Expression db from grp params (nullity 'PGbool)

1280−gtAny = unsafeSubqueryExpression "> ANY"

1281−

1282−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1283−-- >>> printSQL $ myRow `rowGtAny` values_ myRow

1284−-- ROW(1, FALSE) > ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1285−rowGtAny

1286− :: SListI row

1287− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1288− -> Query db params row -- ^ subquery

1289− -> Expression db from grp params (nullity 'PGbool)

1290−rowGtAny = unsafeRowSubqueryExpression "> ANY"

1291−

1292−-- | >>> printSQL $ true `gteAll` values_ (true `as` #foo)

1293−-- TRUE >= ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1294−gteAll

1295− :: Expression db from grp params ty -- ^ expression

1296− -> Query db params '[alias ::: ty] -- ^ subquery

1297− -> Expression db from grp params (nullity 'PGbool)

1298−gteAll = unsafeSubqueryExpression ">= ALL"

1299−

1300−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1301−-- >>> printSQL $ myRow `rowGteAll` values_ myRow

1302−-- ROW(1, FALSE) >= ALL (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1303−rowGteAll

1304− :: SListI row

1305− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1306− -> Query db params row -- ^ subquery

1307− -> Expression db from grp params (nullity 'PGbool)

1308−rowGteAll = unsafeRowSubqueryExpression ">= ALL"

1309−

1310−-- | >>> printSQL $ true `gteAny` values_ (true `as` #foo)

1311−-- TRUE >= ANY (SELECT * FROM (VALUES (TRUE)) AS t ("foo"))

1312−gteAny

1313− :: Expression db from grp params ty -- ^ expression

1314− -> Query db params '[alias ::: ty] -- ^ subquery

1315− -> Expression db from grp params (nullity 'PGbool)

1316−gteAny = unsafeSubqueryExpression ">= ANY"

1317−

1318−-- | >>> let myRow = 1 `as` #foo :* false `as` #bar :: NP (Aliased (Expression db from grp params)) '["foo" ::: 'NotNull 'PGint2, "bar" ::: 'NotNull 'PGbool]

1319−-- >>> printSQL $ myRow `rowGteAny` values_ myRow

1320−-- ROW(1, FALSE) >= ANY (SELECT * FROM (VALUES (1, FALSE)) AS t ("foo", "bar"))

1321−rowGteAny

1322− :: SListI row

1323− => NP (Aliased (Expression db from grp params)) row -- ^ row constructor

1324− -> Query db params row -- ^ subquery

1325− -> Expression db from grp params (nullity 'PGbool)

1326−rowGteAny = unsafeRowSubqueryExpression ">= ANY"

1024+instance RenderSQL (HavingClause outer commons grp schemas params from) where

1025+ renderSQL = \case

1026+ NoHaving -> ""

1027+ Having [] -> ""

1028+ Having conditions ->

1029+ " HAVING" <+> commaSeparated (renderSQL <$> conditions)

13271030

13281031-- | A `CommonTableExpression` is an auxiliary statement in a `with` clause.

13291032data CommonTableExpression statement

1033+ (schemas :: SchemasType)

13301034 (params :: [NullityType])

1331− (db0 :: DBType)

1332− (db1 :: DBType) where

1035+ (commons0 :: FromType)

1036+ (commons1 :: FromType) where

13331037 CommonTableExpression

1334− :: Aliased (statement (commons :=> schemas) params) (cte ::: common)

1335− -> CommonTableExpression statement params

1336− (commons :=> schemas) ((cte ::: common ': commons) :=> schemas)

1038+ :: Aliased (statement commons schemas params) (cte ::: common)

1039+ -> CommonTableExpression statement schemas params commons (cte ::: common ': commons)

13371040instance

13381041 ( KnownSymbol cte

1339− , db0 ~ (commons :=> schemas)

1340− , db1 ~ ((cte ::: common ': commons) :=> schemas)

1042+ , commons1 ~ (cte ::: common ': commons)

13411043 ) => Aliasable cte

1342− (statement db0 params common)

1343− (CommonTableExpression statement params db0 db1) where

1044+ (statement commons schemas params common)

1045+ (CommonTableExpression statement schemas params commons commons1) where

13441046 statement `as` cte = CommonTableExpression (statement `as` cte)

13451047instance

13461048 ( KnownSymbol cte

1347− , db0 ~ (commons :=> schemas)

1348− , db1 ~ ((cte ::: common ': commons) :=> schemas)

1049+ , commons1 ~ (cte ::: common ': commons)

13491050 ) => Aliasable cte

1350− (statement db0 params common)

1351− (AlignedList (CommonTableExpression statement params) db0 db1) where

1352− statement `as` cte = single (statement `as` cte)

1353−-- instance

1354−-- ( KnownSymbol vw

1355−-- , Has "public" db schema

1356−-- , Alter "public" (vw ::: 'View cte ': schema) db ~ db1

1357−-- ) => Aliasable vw (statement db params cte)

1358−-- (AlignedList (CommonTableExpression statement params) db db1) where

1359−-- statement `as` vw = single (statement `as` vw)

1360−

1361−-- | render a `CommonTableExpression`.

1362−renderCommonTableExpression

1363− :: (forall db ps row. statement db ps row -> ByteString) -- ^ render statement

1364− -> CommonTableExpression statement params db0 db1 -> ByteString

1365−renderCommonTableExpression renderStatement

1366− (CommonTableExpression (statement `As` alias)) =

1367− renderAlias alias <+> "AS" <+> parenthesized (renderStatement statement)

1368−

1369−-- | render a non-empty `AlignedList` of `CommonTableExpression`s.

1370−renderCommonTableExpressions

1371− :: (forall db ps row. statement db ps row -> ByteString) -- ^ render statement

1372− -> CommonTableExpression statement params db0 db1

1373− -> AlignedList (CommonTableExpression statement params) db1 db2

1374− -> ByteString

1375−renderCommonTableExpressions renderStatement cte ctes =

1376− renderCommonTableExpression renderStatement cte <> case ctes of

1377− Done -> ""

1378− cte' :>> ctes' -> "," <+>

1379− renderCommonTableExpressions renderStatement cte' ctes'

1051+ (statement commons schemas params common)

1052+ (Path (CommonTableExpression statement schemas params) commons commons1) where

1053+ statement `as` cte = csingleton (statement `as` cte)

1054+

1055+instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL

1056+ (CommonTableExpression statement schemas params commons0 commons1) where

1057+ renderSQL (CommonTableExpression (statement `As` cte)) =

1058+ renderSQL cte <+> "AS" <+> parenthesized (renderSQL statement)

13801059

13811060-- | `with` provides a way to write auxiliary statements for use in a larger query.

13821061-- These statements, referred to as `CommonTableExpression`s, can be thought of as

13831062-- defining temporary tables that exist just for one query.

13841063class With statement where

13851064 with

1386− :: AlignedList (CommonTableExpression statement params) db0 db1

1065+ :: Path (CommonTableExpression statement schemas params) commons0 commons1

13871066 -- ^ common table expressions

1388− -> statement db1 params row

1067+ -> statement commons1 schemas params row

13891068 -- ^ larger query

1390− -> statement db0 params row

1391−instance With Query where

1392− with Done query = UnsafeQuery $ renderQuery query

1393− with (cte :>> ctes) query = UnsafeQuery $

1394− "WITH" <+> renderCommonTableExpressions renderQuery cte ctes

1395− <+> renderQuery query

1069+ -> statement commons0 schemas params row

1070+instance With (Query outer) where

1071+ with Done query = query

1072+ with ctes query = UnsafeQuery $

1073+ "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL query

1074+

1075+{- |

1076+>>> import Data.Monoid (Sum (..))

1077+>>> import Data.Int (Int64)

1078+>>> :{

1079+ let

1080+ query :: Query_ schema () (Sum Int64)

1081+ query = withRecursive

1082+ ( values_ ((1 & astype int) `as` #n)

1083+ `unionAll`

1084+ select_ ((#n + 1) `as` #n)

1085+ (from (common #t) & where_ (#n .< 100)) `as` #t )

1086+ ( select_ (fromNull 0 (sum_ (All #n)) `as` #getSum) (from (common #t) & groupBy Nil))

1087+ in printSQL query

1088+:}

1089+WITH RECURSIVE "t" AS ((SELECT * FROM (VALUES ((1 :: int))) AS t ("n")) UNION ALL (SELECT ("n" + 1) AS "n" FROM "t" AS "t" WHERE ("n" < 100))) SELECT COALESCE(sum(ALL "n"), 0) AS "getSum" FROM "t" AS "t"

1090+-}

1091+withRecursive

1092+ :: Aliased (Query outer (recursive ': commons) schemas params) recursive

1093+ -> Query outer (recursive ': commons) schemas params row

1094+ -> Query outer commons schemas params row

1095+withRecursive (recursive `As` cte) query = UnsafeQuery $

1096+ "WITH RECURSIVE" <+> renderSQL cte

1097+ <+> "AS" <+> parenthesized (renderSQL recursive)

1098+ <+> renderSQL query

squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+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+216−538

@@ -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

@@ -39,79 +39,48 @@ 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 (..)

47+ , IndexType (..)

48+ , FunctionType

49+ , OperatorType (..)

50+ , ReturnsType (..)

5651 , SchemaType

5752 , SchemasType

5853 , Public

59− , DBType

60− , DBof

6154 -- * Constraints

6255 , (:=>)

6356 , ColumnConstraint (..)

6457 , TableConstraint (..)

6558 , TableConstraints

6659 , Uniquely

67− -- * Aliases

68− , (:::)

69− , Alias (..)

70− , IsLabel (..)

71− , renderAlias

72− , renderAliasString

73− , renderAliases

74− , Aliased (As)

75− , Aliasable (as)

76− , renderAliasedAs

77− , Has

78− , HasUnique

79− , HasAll

80− , QualifiedAlias (..)

81− , IsQualified (..)

82− , renderQualifiedAlias

8360 -- * Enumerated Labels

8461 , IsPGlabel (..)

8562 , PGlabel (..)

86− , renderLabel

87− , renderLabels

88− , LabelsPG

89− -- * Grouping

90− , Grouping (..)

91− , GroupedBy

92− -- * Aligned lists

93− , AlignedList (..)

94− , single

9563 -- * Data Definitions

9664 , Create

65+ , CreateIfNotExists

66+ , CreateOrReplace

9767 , Drop

68+ , DropSchemum

69+ , DropIfExists

70+ , DropSchemumIfExists

9871 , Alter

72+ , AlterIfExists

9973 , Rename

74+ , RenameIfExists

75+ , ConstraintInvolves

10076 , DropIfConstraintsInvolve

101− -- * Lists

102− , Join

103− , Elem

104− , In

105− , Length

77+ , IsNotElem

78+ , AllUnique

10679 -- * Type Classifications

107− , HasOid (..)

10880 , PGNum

10981 , PGIntegral

11082 , PGFloating

11183 , PGTypeOf

112− , PGArrayOf

113− , PGArray

114− , PGTextArray

11584 , PGJsonType

11685 , PGJsonKey

11786 , SamePGType

@@ -123,41 +92,27 @@ module Squeal.PostgreSQL.Schema

12392 , NullifyFrom

12493 -- * Table Conversions

12594 , TableToColumns

95+ , ColumnsToRow

12696 , TableToRow

12797 ) where

12898

12999import Control.Category

130−import Control.DeepSeq

131−import Data.Aeson (Value)

132−import Data.ByteString (ByteString)

133−import Data.Int (Int16, Int32, Int64)

134100import Data.Kind

135101import Data.Monoid hiding (All)

136−import Data.Scientific (Scientific)

137−import Data.String

138−import Data.Text (Text)

139−import Data.Time

140−import Data.Word (Word16, Word32, Word64)

141102import Data.Type.Bool

142−import Data.UUID.Types (UUID)

143−import Data.Vector (Vector)

144103import Generics.SOP

145−import Generics.SOP.Record

146−import GHC.OverloadedLabels

147104import GHC.TypeLits

148−import Network.IP.Addr

149105import Prelude hiding (id, (.))

150106

151−import qualified Data.ByteString.Lazy as Lazy

152−import qualified Data.Text.Lazy as Lazy

153−import qualified GHC.Generics as GHC

154−import qualified Generics.SOP.Type.Metadata as Type

155−

107+import Squeal.PostgreSQL.Alias

108+import Squeal.PostgreSQL.List

156109import Squeal.PostgreSQL.Render

157110

111+-- $setup

112+-- >>> import Squeal.PostgreSQL

113+

158114-- | `PGType` is the promoted datakind of PostgreSQL types.

159115--

160−-- >>> import Squeal.PostgreSQL.Schema

161116-- >>> :kind 'PGbool

162117-- 'PGbool :: PGType

163118data PGType

@@ -168,6 +123,7 @@ data PGType

168123 | PGnumeric -- ^ arbitrary precision numeric type

169124 | PGfloat4 -- ^ single precision floating-point number (4 bytes)

170125 | PGfloat8 -- ^ double precision floating-point number (8 bytes)

126+ | PGmoney -- ^ currency amount

171127 | PGchar Nat -- ^ fixed-length character string

172128 | PGvarchar Nat -- ^ variable-length character string

173129 | PGtext -- ^ variable-length character string

@@ -183,39 +139,15 @@ data PGType

183139 | PGjson -- ^ textual JSON data

184140 | PGjsonb -- ^ binary JSON data, decomposed

185141 | PGvararray NullityType -- ^ variable length array

186− | PGfixarray Nat NullityType -- ^ fixed length array

142+ | PGfixarray [Nat] NullityType -- ^ fixed length array

187143 | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.

188144 | PGcomposite RowType -- ^ a composite type represents the structure of a row or record; it is essentially just a list of field names and their data types.

145+ | PGtsvector -- ^ A tsvector value is a sorted list of distinct lexemes, which are words that have been normalized to merge different variants of the same word.

146+ | PGtsquery -- ^ A tsquery value stores lexemes that are to be searched for.

147+ | PGoid -- Object identifiers (OIDs) are used internally by PostgreSQL as primary keys for various system tables.

148+ | PGrange PGType -- ^ Range types are data types representing a range of values of some element type (called the range's subtype).

189149 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types

190150

191−-- | The object identifier of a `PGType`.

192−--

193−-- >>> :set -XTypeApplications

194−-- >>> oid @'PGbool

195−-- 16

196−class HasOid (ty :: PGType) where oid :: Word32

197−instance HasOid 'PGbool where oid = 16

198−instance HasOid 'PGint2 where oid = 21

199−instance HasOid 'PGint4 where oid = 23

200−instance HasOid 'PGint8 where oid = 20

201−instance HasOid 'PGnumeric where oid = 1700

202−instance HasOid 'PGfloat4 where oid = 700

203−instance HasOid 'PGfloat8 where oid = 701

204−instance HasOid ('PGchar n) where oid = 18

205−instance HasOid ('PGvarchar n) where oid = 1043

206−instance HasOid 'PGtext where oid = 25

207−instance HasOid 'PGbytea where oid = 17

208−instance HasOid 'PGtimestamp where oid = 1114

209−instance HasOid 'PGtimestamptz where oid = 1184

210−instance HasOid 'PGdate where oid = 1082

211−instance HasOid 'PGtime where oid = 1083

212−instance HasOid 'PGtimetz where oid = 1266

213−instance HasOid 'PGinterval where oid = 1186

214−instance HasOid 'PGuuid where oid = 2950

215−instance HasOid 'PGinet where oid = 869

216−instance HasOid 'PGjson where oid = 114

217−instance HasOid 'PGjsonb where oid = 3802

218−

219151-- | `NullityType` encodes the potential presence or definite absence of a

220152-- @NULL@ allowing operations which are sensitive to such to be well typed.

221153--

@@ -234,11 +166,6 @@ data NullityType

234166type (:=>) constraint ty = '(constraint,ty)

235167infixr 7 :=>

236168

237−-- | The alias operator `:::` is like a promoted version of `As`,

238−-- a type level pair between an alias and some type.

239−type (:::) (alias :: Symbol) ty = '(alias,ty)

240−infixr 6 :::

241−

242169-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.

243170-- A column can be assigned a default value.

244171-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also

@@ -280,7 +207,13 @@ data TableConstraint

280207 | PrimaryKey [Symbol]

281208 | ForeignKey [Symbol] Symbol [Symbol]

282209

283−-- | A `TableConstraints` is a row of `TableConstraint`s.

210+{- | A `TableConstraints` is a row of `TableConstraint`s.

211+

212+>>> :{

213+type family UsersConstraints :: TableConstraints where

214+ UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]

215+:}

216+-}

284217type TableConstraints = [(Symbol,TableConstraint)]

285218

286219-- | A `ForeignKey` must reference columns that either are

@@ -306,7 +239,7 @@ type family Uniquely

306239type TableType = (TableConstraints,ColumnsType)

307240

308241{- | A `RowType` is a row of `NullityType`. They correspond to Haskell

309−record types by means of `RowPG` and are used in many places.

242+record types by means of `Squeal.PostgreSQL.Binary.RowPG` and are used in many places.

310243

311244>>> :{

312245type family PersonRow :: RowType where

@@ -327,9 +260,19 @@ type FromType = [(Symbol,RowType)]

327260

328261-- | `ColumnsToRow` removes column constraints.

329262type family ColumnsToRow (columns :: ColumnsType) :: RowType where

330− ColumnsToRow '[] = '[]

331− ColumnsToRow (column ::: constraint :=> ty ': columns) =

263+ ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': column5 ::: _ :=> ty5 ': columns) =

264+ column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': ColumnsToRow columns

265+ ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': columns) =

266+ column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': ColumnsToRow columns

267+ ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': columns) =

268+ column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': ColumnsToRow columns

269+ ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': columns) =

270+ column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': ColumnsToRow columns

271+ ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': columns) =

272+ column ::: ty ': column1 ::: ty1 ': ColumnsToRow columns

273+ ColumnsToRow (column ::: _ :=> ty ': columns) =

332274 column ::: ty ': ColumnsToRow columns

275+ ColumnsToRow '[] = '[]

333276

334277-- | `TableToColumns` removes table constraints.

335278type family TableToColumns (table :: TableType) :: ColumnsType where

@@ -339,176 +282,6 @@ type family TableToColumns (table :: TableType) :: ColumnsType where

339282type family TableToRow (table :: TableType) :: RowType where

340283 TableToRow tab = ColumnsToRow (TableToColumns tab)

341284

342−-- | `Grouping` is an auxiliary namespace, created by

343−-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used

344−-- for typesafe aggregation

345−data Grouping

346− = Ungrouped -- ^ no aggregation permitted

347− | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped

348−

349−{- | A `GroupedBy` constraint indicates that a table qualified column is

350−a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,

351−may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.

352−-}

353−class (KnownSymbol table, KnownSymbol column)

354− => GroupedBy table column bys where

355−instance {-# OVERLAPPING #-} (KnownSymbol table, KnownSymbol column)

356− => GroupedBy table column ('(table,column) ': bys)

357−instance {-# OVERLAPPABLE #-}

358− ( KnownSymbol table

359− , KnownSymbol column

360− , GroupedBy table column bys

361− ) => GroupedBy table column (tabcol ': bys)

362−

363−-- | `Alias`es are proxies for a type level string or `Symbol`

364−-- and have an `IsLabel` instance so that with @-XOverloadedLabels@

365−--

366−-- >>> :set -XOverloadedLabels

367−-- >>> #foobar :: Alias "foobar"

368−-- Alias

369−data Alias (alias :: Symbol) = Alias

370− deriving (Eq,GHC.Generic,Ord,Show,NFData)

371−instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where

372− fromLabel = Alias

373−instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where

374− fromLabel = fromLabel :* Nil

375−instance KnownSymbol alias => RenderSQL (Alias alias) where renderSQL = renderAlias

376−

377−-- | >>> renderAlias #jimbob

378−-- "\"jimbob\""

379−renderAlias :: KnownSymbol alias => Alias alias -> ByteString

380−renderAlias = doubleQuoted . fromString . symbolVal

381−

382−-- | >>> renderAliasString #ohmahgerd

383−-- "'ohmahgerd'"

384−renderAliasString :: KnownSymbol alias => Alias alias -> ByteString

385−renderAliasString = singleQuotedText . fromString . symbolVal

386−

387−-- | >>> import Generics.SOP (NP(..))

388−-- >>> renderAliases (#jimbob :* #kandi)

389−-- ["\"jimbob\"","\"kandi\""]

390−renderAliases

391− :: All KnownSymbol aliases => NP Alias aliases -> [ByteString]

392−renderAliases = hcollapse

393− . hcmap (Proxy @KnownSymbol) (K . renderAlias)

394−

395−-- | The `As` operator is used to name an expression. `As` is like a demoted

396−-- version of `:::`.

397−--

398−-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)

399−-- As (Just "hello") Alias

400−data Aliased expression aliased where

401− As

402− :: KnownSymbol alias

403− => expression ty

404− -> Alias alias

405− -> Aliased expression (alias ::: ty)

406−deriving instance Show (expression ty)

407− => Show (Aliased expression (alias ::: ty))

408−deriving instance Eq (expression ty)

409− => Eq (Aliased expression (alias ::: ty))

410−deriving instance Ord (expression ty)

411− => Ord (Aliased expression (alias ::: ty))

412−instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)

413− => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where

414− fromLabel = fromLabel @alias2 `As` fromLabel @alias1

415−

416−-- | The `Aliasable` class provides a way to scrap your `Nil`s

417−-- in an `NP` list of `Aliased` expressions.

418−class KnownSymbol alias => Aliasable alias expression aliased

419− | aliased -> expression

420− , aliased -> alias

421− where as :: expression -> Alias alias -> aliased

422−instance (KnownSymbol alias, alias ~ alias1) => Aliasable alias

423− (expression ty)

424− (Aliased expression (alias1 ::: ty))

425− where

426− as = As

427−instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias

428− (expression ty)

429− (NP (Aliased expression) tys)

430− where

431− expression `as` alias = expression `As` alias :* Nil

432−

433−-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")

434−-- >>> renderAliasedAs renderMaybe (Just (3::Int) `As` #an_int)

435−-- "Just AS \"an_int\""

436−renderAliasedAs

437− :: (forall ty. expression ty -> ByteString)

438− -> Aliased expression aliased

439− -> ByteString

440−renderAliasedAs render (expression `As` alias) =

441− render expression <> " AS " <> renderAlias alias

442−

443−-- | @HasUnique alias fields field@ is a constraint that proves that

444−-- @fields@ is a singleton of @alias ::: field@.

445−type HasUnique alias fields field = fields ~ '[alias ::: field]

446−

447−-- | @Has alias fields field@ is a constraint that proves that

448−-- @fields@ has a field of @alias ::: field@, inferring @field@

449−-- from @alias@ and @fields@.

450−class KnownSymbol alias =>

451− Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)

452− | alias fields -> field where

453−instance {-# OVERLAPPING #-} KnownSymbol alias

454− => Has alias (alias ::: field ': fields) field

455−instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)

456− => Has alias (field' ': fields) field

457−

458−-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer

459−-- a list of @subfields@.

460−class

461− ( All KnownSymbol aliases

462− ) => HasAll

463− (aliases :: [Symbol])

464− (fields :: [(Symbol,kind)])

465− (subfields :: [(Symbol,kind)])

466− | aliases fields -> subfields where

467−instance {-# OVERLAPPING #-} HasAll '[] fields '[]

468−instance {-# OVERLAPPABLE #-}

469− (Has alias fields field, HasAll aliases fields subfields)

470− => HasAll (alias ': aliases) fields (alias ::: field ': subfields)

471−

472−-- | Analagous to `IsLabel`, the constraint

473−-- `IsQualified` defines `!` for a column alias qualified

474−-- by a table alias.

475−class IsQualified table column expression where

476− (!) :: Alias table -> Alias column -> expression

477− infixl 9 !

478−instance IsQualified table column (Alias table, Alias column) where (!) = (,)

479−

480−data QualifiedAlias (qualifier :: Symbol) (alias :: Symbol) = QualifiedAlias

481− deriving (Eq,GHC.Generic,Ord,Show,NFData)

482−instance (q ~ q', a ~ a') => IsQualified q a (QualifiedAlias q' a') where

483− _!_ = QualifiedAlias

484−instance (q' ~ "public", a ~ a') => IsLabel a (QualifiedAlias q' a') where

485− fromLabel = QualifiedAlias

486−instance (q0 ~ q1, a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>

487− IsQualified q0 a0 (Aliased (QualifiedAlias q1) (a1 ::: a2)) where

488− _!_ = QualifiedAlias `As` Alias

489−instance (q ~ "public", a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>

490− IsLabel a0 (Aliased (QualifiedAlias q) (a1 ::: a2)) where

491− fromLabel = QualifiedAlias `As` Alias

492−

493−renderQualifiedAlias

494− :: forall q a. (KnownSymbol q, KnownSymbol a)

495− => QualifiedAlias q a -> ByteString

496−renderQualifiedAlias _ =

497− let

498− qualifier = renderAlias (Alias @q)

499− alias = renderAlias (Alias @a)

500− in

501− if qualifier == "\"public\"" then alias else qualifier <> "." <> alias

502−

503−-- | @Elem@ is a promoted `Data.List.elem`.

504−type family Elem x xs where

505− Elem x '[] = 'False

506− Elem x (x ': xs) = 'True

507− Elem x (_ ': xs) = Elem x xs

508−

509−-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

510−type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True

511−

512285-- | Numeric Postgres types.

513286type PGNum =

514287 '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]

@@ -519,37 +292,6 @@ type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]

519292-- | Integral Postgres types.

520293type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]

521294

522−-- | Error message helper for displaying unavailable\/unknown\/placeholder type

523−-- variables whose kind is known.

524−type Placeholder k = 'Text "(_::" :<>: 'ShowType k :<>: 'Text ")"

525−

526−type ErrArrayOf arr ty = arr :<>: 'Text " " :<>: ty

527−type ErrPGfixarrayOf t = ErrArrayOf ('ShowType 'PGfixarray :<>: 'Text " " :<>: Placeholder Nat) t

528−type ErrPGvararrayOf t = ErrArrayOf ('ShowType 'PGvararray) t

529−

530−-- | Ensure a type is a valid array type.

531−type family PGArray name arr :: Constraint where

532− PGArray name ('PGvararray x) = ()

533− PGArray name ('PGfixarray n x) = ()

534− PGArray name val = TypeError

535− ('Text name :<>: 'Text ": Unsatisfied PGArray constraint. Expected either: "

536− :$$: 'Text " • " :<>: ErrPGvararrayOf (Placeholder PGType)

537− :$$: 'Text " • " :<>: ErrPGfixarrayOf (Placeholder PGType)

538− :$$: 'Text "But got: " :<>: 'ShowType val)

539−

540−-- | Ensure a type is a valid array type with a specific element type.

541−type family PGArrayOf name arr ty :: Constraint where

542− PGArrayOf name ('PGvararray x) ty = x ~ ty

543− PGArrayOf name ('PGfixarray n x) ty = x ~ ty

544− PGArrayOf name val ty = TypeError

545− ( 'Text name :<>: 'Text "Unsatisfied PGArrayOf constraint. Expected either: "

546− :$$: 'Text " • " :<>: ErrPGvararrayOf ( 'ShowType ty )

547− :$$: 'Text " • " :<>: ErrPGfixarrayOf ( 'ShowType ty )

548− :$$: 'Text "But got: " :<>: 'ShowType val)

549−

550−-- | Ensure a type is a valid array type whose elements are text.

551−type PGTextArray name arr = PGArrayOf name arr ('NotNull 'PGtext)

552−

553295-- | `PGTypeOf` forgets about @NULL@ and any column constraints.

554296type family PGTypeOf (ty :: NullityType) :: PGType where

555297 PGTypeOf (nullity pg) = pg

@@ -563,14 +305,24 @@ instance ty0 ~ ty1 => SamePGType

563305

564306-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.

565307type family AllNotNull (columns :: ColumnsType) :: Constraint where

308+ AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

309+ AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

310+ AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

311+ AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

312+ AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

313+ AllNotNull (_ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

566314 AllNotNull '[] = ()

567− AllNotNull (column ::: def :=> 'NotNull ty ': columns) = AllNotNull columns

568315

569316-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some

570317-- @NOT NULL@.

571318type family NotAllNull (columns :: ColumnsType) :: Constraint where

572− NotAllNull (column ::: def :=> 'NotNull ty ': columns) = ()

573− NotAllNull (column ::: def :=> 'Null ty ': columns) = NotAllNull columns

319+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

320+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

321+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

322+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

323+ NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

324+ NotAllNull (_ ::: _ :=> 'NotNull _ ': _) = ()

325+ NotAllNull (_ ::: _ :=> 'Null _ ': columns) = NotAllNull columns

574326

575327-- | `NullifyType` is an idempotent that nullifies a `NullityType`.

576328type family NullifyType (ty :: NullityType) :: NullityType where

@@ -579,23 +331,37 @@ type family NullifyType (ty :: NullityType) :: NullityType where

579331

580332-- | `NullifyRow` is an idempotent that nullifies a `RowType`.

581333type family NullifyRow (columns :: RowType) :: RowType where

582− NullifyRow '[] = '[]

334+ NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': columns) =

335+ column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': column5 ::: NullifyType ty5 ': NullifyRow columns

336+ NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': columns) =

337+ column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': NullifyRow columns

338+ NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': columns) =

339+ column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': NullifyRow columns

340+ NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': columns) =

341+ column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': NullifyRow columns

342+ NullifyRow (column ::: ty ': column1 ::: ty1 ': columns) =

343+ column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': NullifyRow columns

583344 NullifyRow (column ::: ty ': columns) =

584345 column ::: NullifyType ty ': NullifyRow columns

346+ NullifyRow '[] = '[]

585347

586348-- | `NullifyFrom` is an idempotent that nullifies a `FromType`

587349-- used to nullify the left or right hand side of an outer join

588350-- in a `Squeal.PostgreSQL.Query.FromClause`.

589351type family NullifyFrom (tables :: FromType) :: FromType where

590− NullifyFrom '[] = '[]

352+ NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': table5 ::: columns5 ': tables) =

353+ table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns5 ': table5 ::: NullifyRow columns4 ': NullifyFrom tables

354+ NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': tables) =

355+ table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns4 ': NullifyFrom tables

356+ NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': tables) =

357+ table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': NullifyFrom tables

358+ NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': tables) =

359+ table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': NullifyFrom tables

360+ NullifyFrom (table ::: columns ': table1 ::: columns1 ': tables) =

361+ table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': NullifyFrom tables

591362 NullifyFrom (table ::: columns ': tables) =

592363 table ::: NullifyRow columns ': NullifyFrom tables

593−

594−-- | `Join` is simply promoted `++` and is used in @JOIN@s in

595−-- `Squeal.PostgreSQL.Query.FromClause`s.

596−type family Join xs ys where

597− Join '[] ys = ys

598− Join (x ': xs) ys = x ': Join xs ys

364+ NullifyFrom '[] = '[]

599365

600366-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in

601367-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@

@@ -605,30 +371,101 @@ type family Create alias x xs where

605371 Create alias x (alias ::: y ': xs) = TypeError

606372 ('Text "Create: alias "

607373 ':<>: 'ShowType alias

608− ':<>: 'Text "already in use")

374+ ':<>: 'Text "already exists")

609375 Create alias y (x ': xs) = x ': Create alias y xs

610376

377+type family CreateIfNotExists alias x xs where

378+ CreateIfNotExists alias x '[] = '[alias ::: x]

379+ CreateIfNotExists alias x (alias ::: y ': xs) = alias ::: y ': xs

380+ CreateIfNotExists alias y (x ': xs) = x ': CreateIfNotExists alias y xs

381+

382+type family CreateOrReplace alias x xs where

383+ CreateOrReplace alias x '[] = '[alias ::: x]

384+ CreateOrReplace alias x (alias ::: x ': xs) = alias ::: x ': xs

385+ CreateOrReplace alias x (alias ::: y ': xs) = TypeError

386+ ('Text "CreateOrReplace: expected type "

387+ ':<>: 'ShowType x

388+ ':<>: 'Text " but alias "

389+ ':<>: 'ShowType alias

390+ ':<>: 'Text " has type "

391+ ':<>: 'ShowType y)

392+ CreateOrReplace alias y (x ': xs) = x ': CreateOrReplace alias y xs

393+

611394-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@

612395-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements

613396-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.

614397type family Drop alias xs where

615− Drop alias ((alias ::: x) ': xs) = xs

398+ Drop alias '[] = TypeError

399+ ('Text "Drop: alias "

400+ ':<>: 'ShowType alias

401+ ':<>: 'Text " does not exist" )

402+ Drop alias (alias ::: x ': xs) = xs

616403 Drop alias (x ': xs) = x ': Drop alias xs

617404

405+type family DropSchemum alias sch xs where

406+ DropSchemum alias sch '[] = TypeError

407+ ('Text "DropSchemum: alias "

408+ ':<>: 'ShowType alias

409+ ':<>: 'Text " does not exist" )

410+ DropSchemum alias sch (alias ::: sch x ': xs) = xs

411+ DropSchemum alias sch0 (alias ::: sch1 x ': xs) = TypeError

412+ ('Text "DropSchemum: expected schemum "

413+ ':<>: 'ShowType sch0

414+ ':<>: 'Text " but alias "

415+ ':<>: 'ShowType alias

416+ ':<>: 'Text " has schemum "

417+ ':<>: 'ShowType sch1)

418+ DropSchemum alias sch (x ': xs) = x ': DropSchemum alias sch xs

419+

420+type family DropIfExists alias xs where

421+ DropIfExists alias '[] = '[]

422+ DropIfExists alias (alias ::: x ': xs) = xs

423+ DropIfExists alias (x ': xs) = x ': DropIfExists alias xs

424+

425+type family DropSchemumIfExists alias sch xs where

426+ DropSchemumIfExists alias sch '[] = '[]

427+ DropSchemumIfExists alias sch (alias ::: sch x ': xs) = xs

428+ DropSchemumIfExists alias sch0 (alias ::: sch1 x ': xs) = TypeError

429+ ('Text "DropSchemumIfExists: expected schemum "

430+ ':<>: 'ShowType sch1

431+ ':<>: 'Text " but alias "

432+ ':<>: 'ShowType alias

433+ ':<>: 'Text " has schemum "

434+ ':<>: 'ShowType sch0)

435+ DropSchemumIfExists alias sch (x ': xs) = x ': DropSchemumIfExists alias sch xs

436+

618437-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@

619−-- with the type `x` and is used in `Squeal.PostgreSQL.Definition.alterTable`

438+-- with the type @x@ and is used in `Squeal.PostgreSQL.Definition.alterTable`

620439-- and `Squeal.PostgreSQL.Definition.alterColumn`.

621440type family Alter alias x xs where

441+ Alter alias x '[] = TypeError

442+ ('Text "Alter: alias "

443+ ':<>: 'ShowType alias

444+ ':<>: 'Text " does not exist" )

622445 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

623446 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs

624447

448+type family AlterIfExists alias x xs where

449+ AlterIfExists alias x '[] = '[]

450+ AlterIfExists alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

451+ AlterIfExists alias x1 (x0 ': xs) = x0 ': AlterIfExists alias x1 xs

452+

625453-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@

626454-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and

627455-- `Squeal.PostgreSQL.Definition.renameColumn`.

628456type family Rename alias0 alias1 xs where

457+ Rename alias0 alias1 '[] = TypeError

458+ ('Text "Rename: alias "

459+ ':<>: 'ShowType alias0

460+ ':<>: 'Text " does not exist" )

629461 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs

630462 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs

631463

464+type family RenameIfExists alias0 alias1 xs where

465+ RenameIfExists alias x '[] = '[]

466+ RenameIfExists alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs

467+ RenameIfExists alias0 alias1 (x ': xs) = x ': RenameIfExists alias0 alias1 xs

468+

632469-- | Check if a `TableConstraint` involves a column

633470type family ConstraintInvolves column constraint where

634471 ConstraintInvolves column ('Check columns) = column `Elem` columns

@@ -645,22 +482,35 @@ type family DropIfConstraintsInvolve column constraints where

645482 (DropIfConstraintsInvolve column constraints)

646483 (alias ::: constraint ': DropIfConstraintsInvolve column constraints)

647484

648−{- | Calculate the `Length` of a type level list

649−

650−>>> :kind! Length '[Char,String,Bool,Double]

651−Length '[Char,String,Bool,Double] :: Nat

652−= 4

653−-}

654−type family Length (xs :: [k]) :: Nat where

655− Length (x : xs) = 1 + Length xs

656− Length '[] = 0

657−

658485-- | A `SchemumType` is a user-defined type, either a `Table`,

659486-- `View` or `Typedef`.

660487data SchemumType

661488 = Table TableType

662489 | View RowType

663490 | Typedef PGType

491+ | Index IndexType

492+ | Function FunctionType

493+ | Operator OperatorType

494+ | UnsafeSchemum Symbol

495+

496+type FunctionType = ([NullityType], ReturnsType)

497+

498+data IndexType

499+ = Btree

500+ | Hash

501+ | Gist

502+ | Spgist

503+ | Gin

504+ | Brin

505+

506+data ReturnsType

507+ = Returns NullityType

508+ | ReturnsTable RowType

509+

510+data OperatorType

511+ = BinaryOp NullityType NullityType NullityType

512+ | LeftOp NullityType NullityType

513+ | RightOp NullityType NullityType

664514

665515{- | The schema of a database consists of a list of aliased,

666516user-defined `SchemumType`s.

@@ -686,15 +536,27 @@ type family Schema :: SchemaType where

686536-}

687537type SchemaType = [(Symbol,SchemumType)]

688538

539+{- |

540+A database contains one or more named schemas, which in turn contain tables.

541+The same object name can be used in different schemas without conflict;

542+for example, both schema1 and myschema can contain tables named mytable.

543+Unlike databases, schemas are not rigidly separated:

544+a user can access objects in any of the schemas in the database they are connected to,

545+if they have privileges to do so.

546+

547+There are several reasons why one might want to use schemas:

548+

549+ * To allow many users to use one database without interfering with each other.

550+ * To organize database objects into logical groups to make them more manageable.

551+ * Third-party applications can be put into separate schemas

552+ so they do not collide with the names of other objects.

553+-}

689554type SchemasType = [(Symbol,SchemaType)]

690555

556+-- | A type family to use for a single schema database.

691557type family Public (schema :: SchemaType) :: SchemasType

692558 where Public schema = '["public" ::: schema]

693559

694−type DBType = (FromType,SchemasType)

695−

696−type family DBof :: SchemasType -> DBType where DBof = '(,) '[]

697−

698560-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas

699561-- the overloaded label, `fromLabel` is used for column references,

700562-- `label`s are used for enum terms. A `label` is called with

@@ -706,195 +568,13 @@ instance labels ~ '[label]

706568 => IsPGlabel label (NP PGlabel labels) where label = PGlabel :* Nil

707569-- | A `PGlabel` unit type with an `IsPGlabel` instance

708570data PGlabel (label :: Symbol) = PGlabel

709−-- | Renders a label

710−renderLabel :: KnownSymbol label => proxy label -> ByteString

711−renderLabel (_ :: proxy label) =

712− "\'" <> renderSymbol @label <> "\'"

713−-- | Renders a list of labels

714−renderLabels

715− :: All KnownSymbol labels => NP PGlabel labels -> [ByteString]

716−renderLabels = hcollapse

717− . hcmap (Proxy @KnownSymbol) (K . renderLabel)

718−

719−{- | The `PG` type family embeds a subset of Haskell types

720−as Postgres types. As an open type family, `PG` is extensible.

721−

722−>>> :kind! PG LocalTime

723−PG LocalTime :: PGType

724−= 'PGtimestamp

725−

726−>>> newtype MyDouble = My Double

727−>>> type instance PG MyDouble = 'PGfloat8

728−-}

729−type family PG (hask :: Type) :: PGType

730−type instance PG Bool = 'PGbool

731−type instance PG Int16 = 'PGint2

732−type instance PG Int32 = 'PGint4

733−type instance PG Int64 = 'PGint8

734−type instance PG Word16 = 'PGint2

735−type instance PG Word32 = 'PGint4

736−type instance PG Word64 = 'PGint8

737−type instance PG Scientific = 'PGnumeric

738−type instance PG Float = 'PGfloat4

739−type instance PG Double = 'PGfloat8

740−type instance PG Char = 'PGchar 1

741−type instance PG Text = 'PGtext

742−type instance PG Lazy.Text = 'PGtext

743−type instance PG String = 'PGtext

744−type instance PG ByteString = 'PGbytea

745−type instance PG Lazy.ByteString = 'PGbytea

746−type instance PG LocalTime = 'PGtimestamp

747−type instance PG UTCTime = 'PGtimestamptz

748−type instance PG Day = 'PGdate

749−type instance PG TimeOfDay = 'PGtime

750−type instance PG (TimeOfDay, TimeZone) = 'PGtimetz

751−type instance PG DiffTime = 'PGinterval

752−type instance PG UUID = 'PGuuid

753−type instance PG (NetAddr IP) = 'PGinet

754−type instance PG Value = 'PGjson

755−type instance PG (Json hask) = 'PGjson

756−type instance PG (Jsonb hask) = 'PGjsonb

757−type instance PG (Vector hask) = 'PGvararray (NullPG hask)

758−type instance PG (hask, hask) = 'PGfixarray 2 (NullPG hask)

759−type instance PG (hask, hask, hask) = 'PGfixarray 3 (NullPG hask)

760−type instance PG (hask, hask, hask, hask) = 'PGfixarray 4 (NullPG hask)

761−type instance PG (hask, hask, hask, hask, hask) = 'PGfixarray 5 (NullPG hask)

762−type instance PG (hask, hask, hask, hask, hask, hask)

763− = 'PGfixarray 6 (NullPG hask)

764−type instance PG (hask, hask, hask, hask, hask, hask, hask)

765− = 'PGfixarray 7 (NullPG hask)

766−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask)

767− = 'PGfixarray 8 (NullPG hask)

768−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask, hask)

769− = 'PGfixarray 9 (NullPG hask)

770−type instance PG (hask, hask, hask, hask, hask, hask, hask, hask, hask, hask)

771− = 'PGfixarray 10 (NullPG hask)

772−type instance PG (Composite hask) = 'PGcomposite (RowPG hask)

773−type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)

774−

775−{- | The `Json` newtype is an indication that the Haskell

776−type it's applied to should be stored as `PGjson`.

777−-}

778−newtype Json hask = Json {getJson :: hask}

779− deriving (Eq, Ord, Show, Read, GHC.Generic)

780−

781−{- | The `Jsonb` newtype is an indication that the Haskell

782−type it's applied to should be stored as `PGjsonb`.

783−-}

784−newtype Jsonb hask = Jsonb {getJsonb :: hask}

785− deriving (Eq, Ord, Show, Read, GHC.Generic)

786−

787−{- | The `Composite` newtype is an indication that the Haskell

788−type it's applied to should be stored as a `PGcomposite`.

789−-}

790−newtype Composite record = Composite {getComposite :: record}

791− deriving (Eq, Ord, Show, Read, GHC.Generic)

792−

793−{- | The `Enumerated` newtype is an indication that the Haskell

794−type it's applied to should be stored as `PGenum`.

795−-}

796−newtype Enumerated enum = Enumerated {getEnumerated :: enum}

797− deriving (Eq, Ord, Show, Read, GHC.Generic)

798−

799−{-| The `LabelsPG` type family calculates the constructors of a

800−Haskell enum type.

801−

802−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

803−>>> instance Generic Schwarma

804−>>> instance HasDatatypeInfo Schwarma

805−>>> :kind! LabelsPG Schwarma

806−LabelsPG Schwarma :: [Type.ConstructorName]

807−= '["Beef", "Lamb", "Chicken"]

808−-}

809−type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where

810− LabelsPG hask =

811− ConstructorNamesOf (ConstructorsOf (DatatypeInfoOf hask))

812−

813−{- | `RowPG` turns a Haskell record type into a `RowType`.

814−

815−>>> data Person = Person { name :: Text, age :: Int32 } deriving GHC.Generic

816−>>> instance Generic Person

817−>>> instance HasDatatypeInfo Person

818−>>> :kind! RowPG Person

819−RowPG Person :: [(Symbol, NullityType)]

820−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

821−-}

822−type family RowPG (hask :: Type) :: RowType where

823− RowPG hask = RowOf (RecordCodeOf hask)

824−

825−type family RowOf (fields :: [(Symbol, Type)]) :: RowType where

826− RowOf '[] = '[]

827− RowOf (field ': fields) = FieldPG field ': RowOf fields

828−

829−type family FieldPG (field :: (Symbol, Type)) :: (Symbol, NullityType) where

830− FieldPG (field ::: hask) = field ::: NullPG hask

831−

832−{- | `NullPG` turns a Haskell type into a `NullityType`.

833−

834−>>> :kind! NullPG Double

835−NullPG Double :: NullityType

836−= 'NotNull 'PGfloat8

837−>>> :kind! NullPG (Maybe Double)

838−NullPG (Maybe Double) :: NullityType

839−= 'Null 'PGfloat8

840−-}

841−type family NullPG (hask :: Type) :: NullityType where

842− NullPG (Maybe hask) = 'Null (PG hask)

843− NullPG hask = 'NotNull (PG hask)

844−

845−{- | `TuplePG` turns a Haskell tuple type (including record types) into

846−the corresponding list of `NullityType`s.

847−

848−>>> :kind! TuplePG (Double, Maybe Char)

849−TuplePG (Double, Maybe Char) :: [NullityType]

850−= '['NotNull 'PGfloat8, 'Null ('PGchar 1)]

851−-}

852−type family TuplePG (hask :: Type) :: [NullityType] where

853− TuplePG hask = TupleOf (TupleCodeOf hask (Code hask))

854−

855−type family TupleOf (tuple :: [Type]) :: [NullityType] where

856− TupleOf '[] = '[]

857− TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple

858−

859−type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where

860− TupleCodeOf hask '[tuple] = tuple

861− TupleCodeOf hask '[] =

862− TypeError

863− ( 'Text "The type `" :<>: 'ShowType hask :<>: 'Text "' is not a tuple type."

864− :$$: 'Text "It is a void type with no constructors."

865− )

866− TupleCodeOf hask (_ ': _ ': _) =

867− TypeError

868− ( 'Text "The type `" :<>: 'ShowType hask :<>: 'Text "' is not a tuple type."

869− :$$: 'Text "It is a sum type with more than one constructor."

870− )

871−

872−-- | Calculates constructors of a datatype.

873−type family ConstructorsOf (datatype :: Type.DatatypeInfo)

874− :: [Type.ConstructorInfo] where

875− ConstructorsOf ('Type.ADT _module _datatype constructors) =

876− constructors

877− ConstructorsOf ('Type.Newtype _module _datatype constructor) =

878− '[constructor]

879−

880−-- | Calculates the name of a nullary constructor, otherwise

881−-- generates a type error.

882−type family ConstructorNameOf (constructors :: Type.ConstructorInfo)

883− :: Type.ConstructorName where

884− ConstructorNameOf ('Type.Constructor name) = name

885− ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError

886− ('Text "ConstructorNameOf error: non-nullary constructor "

887− ':<>: 'Text name)

888− ConstructorNameOf ('Type.Record name _fields) = TypeError

889− ('Text "ConstructorNameOf error: non-nullary constructor "

890− ':<>: 'Text name)

891−

892−-- | Calculate the names of nullary constructors.

893−type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])

894− :: [Type.ConstructorName] where

895− ConstructorNamesOf '[] = '[]

896− ConstructorNamesOf (constructor ': constructors) =

897− ConstructorNameOf constructor ': ConstructorNamesOf constructors

571+instance KnownSymbol label => RenderSQL (PGlabel label) where

572+ renderSQL _ = "\'" <> renderSymbol @label <> "\'"

573+instance All KnownSymbol labels => RenderSQL (NP PGlabel labels) where

574+ renderSQL

575+ = commaSeparated

576+ . hcollapse

577+ . hcmap (Proxy @KnownSymbol) (K . renderSQL)

898578

899579-- | Is a type a valid JSON key?

900580type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]

@@ -902,17 +582,15 @@ type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]

902582-- | Is a type a valid JSON type?

903583type PGJsonType = '[ 'PGjson, 'PGjsonb ]

904584

905−-- | An `AlignedList` is a type-aligned list or free category.

906−data AlignedList p x0 x1 where

907− Done :: AlignedList p x x

908− (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2

909−infixr 7 :>>

910−instance Category (AlignedList p) where

911− id = Done

912− (.) list = \case

913− Done -> list

914− step :>> steps -> step :>> (steps >>> list)

915−

916−-- | A `single` step.

917−single :: p x0 x1 -> AlignedList p x0 x1

918−single step = step :>> Done

585+-- | Utility class for `AllUnique` to provide nicer error messages.

586+class IsNotElem x isElem where

587+instance IsNotElem x 'False where

588+instance (TypeError ( 'Text "Cannot assign to "

589+ ':<>: 'ShowType alias

590+ ':<>: 'Text " more than once"))

591+ => IsNotElem '(alias, a) 'True where

592+

593+-- | No elem of @xs@ appears more than once, in the context of assignment.

594+class AllUnique (xs :: [(Symbol, a)]) where

595+instance AllUnique '[] where

596+instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where

squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+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 schemas 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 schemas 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 schemas 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 schemas 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 schemas 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 schemas0 schemas1 io x

90− -> PQ schemas0 schemas1 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 schemas0 schemas1 io x

103− -> PQ schemas0 schemas1 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/Doc.hsnew file+6

@@ -0,0 +1,6 @@

1+module Main (main) where

3+import Test.DocTest

5+main :: IO ()

6+main = doctest [ "-isrc", "src" ]

squeal-postgresql/test/DocTest.hsdeleted−18

@@ -1,18 +0,0 @@

1−module Main (main) where

2−

3−import Test.DocTest

4−

5−main :: IO ()

6−main = doctest

7− [ "-isrc"

8− , "src/Squeal/PostgreSQL.hs"

9− , "src/Squeal/PostgreSQL/Binary.hs"

10− , "src/Squeal/PostgreSQL/Definition.hs"

11− , "src/Squeal/PostgreSQL/Manipulation.hs"

12− , "src/Squeal/PostgreSQL/Query.hs"

13− , "src/Squeal/PostgreSQL/Expression.hs"

14− , "src/Squeal/PostgreSQL/PQ.hs"

15− , "src/Squeal/PostgreSQL/Migration.hs"

16− , "src/Squeal/PostgreSQL/Transaction.hs"

17− , "src/Squeal/PostgreSQL/Pool.hs"

18− ]

squeal-postgresql/test/Property.hsnew file+166

@@ -0,0 +1,166 @@

1+{-# LANGUAGE

2+ DataKinds

3+ , GADTs

4+ , LambdaCase

5+ , OverloadedLabels

6+ , OverloadedStrings

7+ , TypeApplications

8+ , TypeOperators

9+#-}

10+

11+module Main (main) where

12+

13+import Control.Monad.Trans

14+import Data.ByteString (ByteString)

15+import Data.ByteString.Char8 (unpack)

16+import Data.Scientific (fromFloatDigits)

17+import Data.Fixed (Fixed(MkFixed), Micro, Pico)

18+import Data.String (IsString(fromString))

19+import Data.Time

20+import Squeal.PostgreSQL hiding (check, defaultMain, Group)

21+import Hedgehog hiding (Range)

22+import qualified Hedgehog.Gen as Gen

23+import qualified Hedgehog.Main as Main

24+import qualified Hedgehog.Range as Range

25+

26+main :: IO ()

27+main = Main.defaultMain [checkSequential roundtrips]

28+

29+roundtrips :: Group

30+roundtrips = Group "roundtrips"

31+ [ roundtrip int2 genInt16

32+ , roundtrip int4 genInt32

33+ , roundtrip int8 genInt64

34+ , roundtrip bool Gen.bool

35+ , roundtrip numeric genScientific

36+ , roundtrip float4 genFloat

37+ , roundtrip float8 genDouble

38+ , roundtripOn normalizeTimeOfDay time genTimeOfDay

39+ -- , roundtrip timetz genTimeWithZone normalizeTimeWithZone

40+ , roundtripOn normalizeLocalTime timestamp genLocalTime

41+ , roundtrip timestamptz genUTCTime

42+ , roundtrip date genDay

43+ , roundtrip interval genDiffTime

44+ , roundtripOn normalizeIntRange int4range (genRange genInt32)

45+ , roundtripOn normalizeIntRange int8range (genRange genInt64)

46+ , roundtrip numrange (genRange genScientific)

47+ , roundtripOn (fmap normalizeLocalTime) tsrange (genRange genLocalTime)

48+ , roundtrip tstzrange (genRange genUTCTime)

49+ , roundtripOn normalizeIntRange daterange (genRange genDay)

50+ ]

51+ where

52+ genInt16 = Gen.int16 Range.exponentialBounded

53+ genInt32 = Gen.int32 Range.exponentialBounded

54+ genInt64 = Gen.int64 Range.exponentialBounded

55+ genScientific = fromFloatDigits <$> genFloat

56+ genPosFloat = Gen.float

57+ (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)

58+ genFloat = Gen.prune $ Gen.choice

59+ [ genPosFloat

60+ , negate <$> genPosFloat

61+ , Gen.element [0,1/0] ]

62+ genPosDouble = Gen.double

63+ (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)

64+ genDouble = Gen.prune $ Gen.choice

65+ [ genPosDouble

66+ , negate <$> genPosDouble

67+ , Gen.element [0,1/0] ]

68+ genRange gen = do

69+ lb <- gen

70+ ub <- Gen.filter (lb <) gen

71+ Gen.element

72+ [ Empty, singleton lb, whole

73+ , lb <=..<= ub , lb <=..< ub, lb <..<= ub, lb <..< ub

74+ , atLeast lb, moreThan lb, atMost ub, lessThan ub ]

75+ genDay = do

76+ y <- toInteger <$> Gen.int (Range.constant 2000 2019)

77+ m <- Gen.int (Range.constant 1 12)

78+ d <- Gen.int (Range.constant 1 28)

79+ return $ fromGregorian y m d

80+ genDiffTime = secondsToDiffTime . toInteger <$>

81+ Gen.int (Range.constant 0 86401)

82+ genUTCTime = UTCTime <$> genDay <*> genDiffTime

83+ genTimeOfDay = do

84+ h <- Gen.int (Range.constant 0 23)

85+ m <- Gen.int (Range.constant 0 59)

86+ s <- MkFixed . toInteger <$> Gen.int (Range.constant 0 59)

87+ return $ TimeOfDay h m s

88+ genLocalTime = LocalTime <$> genDay <*> genTimeOfDay

89+ -- genTimeZone = Gen.element $ map (read @TimeZone)

90+ -- [ "UTC", "UT", "GMT", "EST", "EDT", "CST"

91+ -- , "CDT", "MST", "MDT", "PST", "PDT" ]

92+ -- genTimeWithZone = (,) <$> genTimeOfDay <*> genTimeZone

93+

94+roundtrip

95+ :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)

96+ => TypeExpression schemas ('NotNull ty)

97+ -> Gen x

98+ -> (PropertyName, Property)

99+roundtrip = roundtripOn id

100+

101+roundtripOn

102+ :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)

103+ => (x -> x)

104+ -> TypeExpression schemas ('NotNull ty)

105+ -> Gen x

106+ -> (PropertyName, Property)

107+roundtripOn norm ty gen = propertyWithName $ do

108+ x <- forAll gen

109+ Just (Only y) <- lift . withConnection connectionString $

110+ firstRow =<< runQueryParams

111+ (values_ (parameter @1 ty `as` #fromOnly)) (Only x)

112+ norm x === y

113+ where

114+ propertyWithName prop =

115+ (fromString (unpack (renderSQL ty)), property prop)

116+

117+maxPosFloat :: RealFloat a => a

118+maxPosFloat = x

119+ where

120+ n = floatDigits x

121+ b = floatRadix x

122+ (_, u) = floatRange x

123+ x = encodeFloat (b^n - 1) (u - n)

124+

125+minPosFloat :: RealFloat a => a

126+minPosFloat = x

127+ where

128+ n = floatDigits x

129+ b = floatRadix x

130+ (l, _) = floatRange x

131+ x = encodeFloat (b^n - 1) (l - n - 1)

132+

133+connectionString :: ByteString

134+connectionString = "host=localhost port=5432 dbname=exampledb"

135+

136+normalizeIntRange :: (Enum int, Ord int) => Range int -> Range int

137+normalizeIntRange = \case

138+ Empty -> Empty

139+ NonEmpty l u ->

140+ let

141+ l' = normalizeL l

142+ u' = normalizeU u

143+ in if emptyNormalized l' u' then Empty else NonEmpty l' u'

144+ where

145+ normalizeL = \case

146+ Open l -> Closed (succ l)

147+ normalized -> normalized

148+ normalizeU = \case

149+ Closed u -> Open (succ u)

150+ normalized -> normalized

151+ emptyNormalized (Closed l) (Open u) = l >= u

152+ emptyNormalized _ _ = False

153+

154+normalizeTimeOfDay :: TimeOfDay -> TimeOfDay

155+normalizeTimeOfDay (TimeOfDay h m s) = TimeOfDay h m

156+ . fromRational @Pico

157+ . toRational @Micro

158+ . fromRational @Micro

159+ . toRational @Pico

160+ $ s

161+

162+normalizeLocalTime :: LocalTime -> LocalTime

163+normalizeLocalTime (LocalTime d t) = LocalTime d (normalizeTimeOfDay t)

164+

165+-- normalizeTimeWithZone :: (TimeOfDay, TimeZone) -> (TimeOfDay, TimeZone)

166+-- normalizeTimeWithZone (t, z) = (normalizeTimeOfDay t, z)

squeal-postgresql/test/Spec.hsnew file+136

@@ -0,0 +1,136 @@

1+{-# LANGUAGE

2+ DataKinds

3+ , DeriveAnyClass

4+ , DeriveGeneric

5+ , DerivingStrategies

6+ , DuplicateRecordFields

7+ , FlexibleContexts

8+ , OverloadedLabels

9+ , OverloadedLists

10+ , OverloadedStrings

11+ , TypeApplications

12+ , TypeFamilies

13+ , TypeInType

14+ , TypeOperators

15+#-}

16+

17+module Main (main) where

18+

19+import Control.Concurrent.Async (replicateConcurrently)

20+import Data.ByteString (ByteString)

21+import Data.Int (Int32)

22+import Data.Text (Text)

23+import Test.Hspec

24+

25+import qualified Generics.SOP as SOP

26+import qualified GHC.Generics as GHC

27+

28+import Squeal.PostgreSQL

29+

30+main :: IO ()

31+main = hspec spec

32+

33+type Schemas = Public

34+ '[ "users" ::: 'Table (

35+ '[ "pk_users" ::: 'PrimaryKey '["id"]

36+ , "unique_names" ::: 'Unique '["name"]

37+ ] :=>

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

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

40+

41+data User = User

42+ { userName :: Text

43+ } deriving stock (Eq, Show, GHC.Generic)

44+ deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

45+

46+insertUser :: Manipulation_ Schemas User ()

47+insertUser = insertInto_ #users

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

49+

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

51+setup =

52+ createTable #users

53+ ( serial `as` #id :*

54+ notNullable text `as` #name )

55+ ( primaryKey #id `as` #pk_users :*

56+ unique #name `as` #unique_names )

57+

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

59+teardown = dropTable #users

60+

61+silence :: MonadPQ schemas pq => pq ()

62+silence = manipulate_ $

63+ UnsafeManipulation "SET client_min_messages TO WARNING;"

64+

65+setupDB :: IO ()

66+setupDB = withConnection connectionString $

67+ silence & pqThen (define setup)

68+

69+dropDB :: IO ()

70+dropDB = withConnection connectionString $

71+ silence & pqThen (define teardown)

72+

73+connectionString :: ByteString

74+connectionString = "host=localhost port=5432 dbname=exampledb"

75+

76+spec :: Spec

77+spec = before_ setupDB . after_ dropDB $ do

78+

79+ describe "Exceptions" $ do

80+

81+ let

82+ testUser = User "TestUser"

83+ newUser = manipulateParams_ insertUser

84+ insertUserTwice = newUser testUser >> newUser testUser

85+ err23505 = PQException $ PQState FatalError (Just "23505")

86+ (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")

87+

88+ it "should be thrown for constraint violation" $

89+ withConnection connectionString insertUserTwice

90+ `shouldThrow` (== err23505)

91+

92+ it "should be rethrown for constraint violation in a transaction" $

93+ withConnection connectionString (transactionally_ insertUserTwice)

94+ `shouldThrow` (== err23505)

95+

96+ describe "Pools" $

97+

98+ it "should manage concurrent transactions" $ do

99+ pool <- createConnectionPool

100+ "host=localhost port=5432 dbname=exampledb" 1 0.5 10

101+ let

102+ query :: Query_ (Public '[]) () (Only Char)

103+ query = values_ (literal 'a' `as` #fromOnly)

104+ session = usingConnectionPool pool . transactionally_ $ do

105+ result <- runQuery query

106+ Just (Only chr) <- firstRow result

107+ return chr

108+ chrs <- replicateConcurrently 10 session

109+ chrs `shouldSatisfy` all (== 'a')

110+

111+ describe "Ranges" $

112+

113+ it "should correctly decode ranges" $ do

114+

115+ rangesOut <- withConnection connectionString $ do

116+ let

117+ query :: Query_ (Public '[]) () (Only (Range Int32))

118+ query = values

119+ ( range int4range (atLeast 3) `as` #fromOnly )

120+ [ range int4range (3 <=..< 5) `as` #fromOnly

121+ , range int4range Empty `as` #fromOnly

122+ , range int4range whole `as` #fromOnly ]

123+ getRows =<< runQuery query

124+ (fromOnly <$> rangesOut :: [Range Int32]) `shouldBe`

125+ [ atLeast 3, 3 <=..< 5, Empty, whole ]

126+

127+ describe "Parameters" $ do

128+

129+ it "should run queries that don't reference all their parameters" $ do

130+

131+ out <- withConnection connectionString $ do

132+ let

133+ query :: Query_ (Public '[]) (Char,Int32) (Only Int32)

134+ query = values_ (param @2 `as` #fromOnly)

135+ firstRow =<< runQueryParams query ('a', 3 :: Int32)

136+ (fromOnly <$> out :: Maybe Int32) `shouldBe` Just 3

squeal-postgresql/test/Specs/ExceptionHandling.hsdeleted−126

@@ -1,126 +0,0 @@

1−{-# LANGUAGE DataKinds #-}

2−{-# LANGUAGE DeriveGeneric #-}

3−{-# LANGUAGE DuplicateRecordFields #-}

4−{-# LANGUAGE FlexibleContexts #-}

5−{-# LANGUAGE OverloadedLabels #-}

6−{-# LANGUAGE OverloadedLists #-}

7−{-# LANGUAGE OverloadedStrings #-}

8−{-# LANGUAGE TypeApplications #-}

9−{-# LANGUAGE TypeFamilies #-}

10−{-# LANGUAGE TypeInType #-}

11−{-# LANGUAGE TypeOperators #-}

12−module ExceptionHandling

13− ( specs

14− , User (..)

15− )

16−where

17−

18−import Control.Monad (void)

19−import Control.Monad.Base (MonadBase)

20−import qualified Data.ByteString.Char8 as Char8

21−import Data.Int (Int16)

22−import Data.Text (Text)

23−import Data.Vector (Vector)

24−import qualified Generics.SOP as SOP

25−import qualified GHC.Generics as GHC

26−import Squeal.PostgreSQL

27−import Squeal.PostgreSQL.Migration

28−import Test.Hspec

29−

30−type Schema =

31− '[ "users" ::: 'Table (

32− '[ "pk_users" ::: 'PrimaryKey '["id"]

33− , "unique_names" ::: 'Unique '["name"]

34− ] :=>

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

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

37− , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray ('Null 'PGint2))

38− ])

39− , "emails" ::: 'Table (

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

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

42− ] :=>

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

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

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

46− ])

47− ]

48−

49−type Schemas = Public Schema

50−

51−type DB = DBof Schemas

52−

53−data User =

54− User { userName :: Text

55− , userEmail :: Maybe Text

56− , userVec :: Vector (Maybe Int16) }

57− deriving (Show, GHC.Generic)

58−instance SOP.Generic User

59−instance SOP.HasDatatypeInfo User

60−

61−insertUser :: Manipulation DB '[ 'NotNull 'PGtext, 'NotNull ('PGvararray ('Null 'PGint2))]

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

63−insertUser = insertRows #users

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

65− OnConflictDoRaise (Returning (#id `as` #fromOnly))

66−

67−setup :: Definition (Public '[]) Schemas

68−setup =

69− createTable #users

70− ( serial `as` #id :*

71− (text & notNullable) `as` #name :*

72− (vararray int2 & notNullable) `as` #vec )

73− ( primaryKey #id `as` #pk_users

74− :* unique #name `as` #unique_names )

75− >>>

76− createTable #emails

77− ( serial `as` #id :*

78− (int & notNullable) `as` #user_id :*

79− (text & nullable) `as` #email )

80− ( primaryKey #id `as` #pk_emails :*

81− foreignKey #user_id #users #id

82− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

83−

84−teardown :: Definition Schemas (Public '[])

85−teardown = dropTable #emails >>> dropTable #users

86−

87−migration :: Migration IO (Public '[]) Schemas

88−migration = Migration { name = "test"

89− , up = void $ define setup

90− , down = void $ define teardown }

91−

92−setupDB :: IO ()

93−setupDB = void . withConnection connectionString $

94− migrateUp $ single migration

95−

96−dropDB :: IO ()

97−dropDB = void . withConnection connectionString $

98− migrateDown $ single migration

99−

100−connectionString :: Char8.ByteString

101−connectionString = "host=localhost port=5432 dbname=exampledb"

102−

103−testUser :: User

104−testUser = User "TestUser" Nothing []

105−

106−newUser :: (MonadBase IO m, MonadPQ Schemas m) => User -> m ()

107−newUser u = void $ manipulateParams insertUser (userName u, userVec u)

108−

109−insertUserTwice :: (MonadBase IO m, MonadPQ Schemas m) => m ()

110−insertUserTwice = newUser testUser >> newUser testUser

111−

112−specs :: SpecWith ()

113−specs = before_ setupDB $ after_ dropDB $

114− describe "Exceptions" $ do

115−

116− let

117− dupKeyErr = PQException FatalError (Just "23505")

118− (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")

119−

120− it "should be thrown for unique constraint violation in a manipulation" $

121− withConnection connectionString insertUserTwice

122− `shouldThrow` (== dupKeyErr)

123−

124− it "should be rethrown for unique constraint violation in a manipulation by a transaction" $

125− withConnection connectionString (transactionally_ insertUserTwice)

126− `shouldThrow` (== dupKeyErr)

squeal-postgresql/test/Specs/Specs.hsdeleted−7

@@ -1,7 +0,0 @@

1−module Specs where

2−

3−import Test.Hspec

4−import qualified ExceptionHandling

5−

6−main :: IO ()

7−main = hspec ExceptionHandling.specs

squeal-presentation-raveline.mdnew file+794

@@ -0,0 +1,794 @@

1+# Squeal

3+_A bridge between SQL and Haskell_

5+by [@Raveline](https://github.com/raveline)

7+---

9+# Rationale

10+

11+Using `postgresql-simple` you have a typical "Trial, error, despair" workflow:

12+

13+- Write query manually or semi-automatically

14+

15+- Write haskell code using the query

16+

17+- Pray that the query syntax is correct

18+

19+- Pray that it returns what you want

20+

21+- Realize the inefficiency of prayer when it comes to SQL

22+

23+- Iterate till it works

24+

25+---

26+

27+![Can't take this anymore](http://gif.eraveline.eu/static/img/0x16e.gif)

28+

29+---

30+

31+# Use your best friend: GHC

32+

33+Squeal provides several eDSL to make your SQL typesafe:

34+

35+- Type level eDSL to express schema;

36+

37+- Value level eDSL to manipulate schema (plus migration, yeehaw !);

38+

39+- Type level eDSL to express queries;

40+

41+- Value level eDSL to perform queries

42+

43+However, it's not an ORM. There's no caching, lazy loading - you retain control over your memory. Also, joins - and mostly aggregation after joins - have to be handled manually.

44+

45+---

46+

47+# Part I. Schema & migration

48+

49+---

50+

51+# The Schema

52+

53+- The schema will be used to validate _everything_: migration, queries, etc.

54+

55+- A schema is mostly a collection of tables.

56+

57+- In this presentation, we will create a very basic database modeling a parliament. We will store _members of parliament_ and _parliamentary groups_.

58+

59+- A simple Schema to represent a Parliament could be:

60+

61+```haskell

62+type Schema = '[ "mp" ::: 'Table MemberOfParliament

63+ , "groupp" ::: 'Table ParliamentGroup ]

64+```

65+

66+---

67+

68+> _note_ We need the `DataKinds` extension to be able to express heterogenous lists containing

69+> specific types like this one.

70+

71+> You can perfectly call your table "group" and not "groupp" even though it is a

72+> keyword in SQL - Squeal queries will be properly escaped.

73+

74+---

75+

76+# A small example

77+

78+```haskell

79+type ParliamentaryGroup =

80+ '[ "pk_groupp" ::: 'PrimaryKey '["groupp_id"]]

81+ :=>

82+ '[ "groupp_id" ::: 'NoDef :=> 'NotNull 'PGuuid

83+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

84+ ]

85+```

86+

87+- That's a whole simple table defined in one go.

88+

89+- `:::` lets us define a column or a constraint.

90+

91+- `:=>` associates the constraints to the column.

92+

93+- Let's split constraints and column to study the syntax a bit more.

94+

95+---

96+

97+> _note_ We are using `:::` and `:=>` to quickly express associations when writing

98+> our schema. We need the `TypeOperators` extension.]

99+

100+---

101+

102+![What does this means ?!](http://gif.eraveline.eu/static/img/0x27e.gif)

103+

104+---

105+

106+# Defining a table

107+

108+```haskell

109+type MemberOfParliament =

110+ '[ "pk_mp" ::: 'PrimaryKey '["mp_id"]

111+ , "fk_mp_groupp" ::: 'ForeignKey '["mp_group"] "groupp" '["groupp_id"]

112+ ] :=> MpCols

113+```

114+

115+- A table is a collection of constraints associated to a collection of columns.

116+

117+- We defined a table named "mp".

118+

119+- It has a constraint named "pk_mp", defining its primary key on column "mp_id".

120+

121+- It has a constraint named "fk_mp_groupp" defining a foreign key on column "mg_group", connected to the column "groupp_id" of table "groupp".

122+

123+- These constraints will be associated to the columns defined in `MpCols`.

124+

125+---

126+

127+# Defining columns

128+

129+```haskell

130+type MpCols =

131+ '[ "mp_id" ::: 'NoDef :=> 'NotNull 'PGuuid

132+ , "first_name" ::: 'NoDef :=> 'NotNull 'PGtext

133+ , "last_name" ::: 'NoDef :=> 'NotNull 'PGtext

134+ ]

135+```

136+

137+- A listing of column associate, for each element:

138+

139+ * a name;

140+

141+ * the mention of an eventual default value;

142+

143+ * the nullability;

144+

145+ * the type (obviously).

146+

147+---

148+

149+> _note_ GHC is already helping. If I named the "mp_id" column differently,

150+> GHC would yell because I promised a primary key constraint on a column named `mp_id`, so there must be one.]

151+

152+---

153+

154+# Implementating the schema

155+

156+- We will carry this schema type pretty much everywhere.

157+

158+- But before we play with this schema, we need to implement it.

159+

160+---

161+

162+```haskell

163+setup :: Definition '[] Schema

164+setup =

165+ createTable #groupp

166+ ( notNullable uuid `as` #groupp_id

167+ :* notNullable text `as` #name)

168+ ( primaryKey #groupp_id `as` #pk_groupp )

169+ >>> createTable #mp

170+ ( notNullable uuid `as` #mp_id

171+ :* notNullable text `as` #first_name

172+ :* notNullable text `as` #last_name

173+ :* notNullable text `as` #mp_group)

174+ ( primaryKey #mp_id `as` #pk_mp

175+ :* foreignKey #mp_group #groupp #groupp_id

176+ OnDeleteCascade OnUpdateCascade

177+ `as` #fk_mp_groupp)

178+```

179+

180+---

181+

182+# Damn, that's verbose

183+

184+- Yes. But you need verbosity to get type safety.

185+

186+- On the plus side, it's fairly straightforward.

187+

188+- You use `:*` to compose the element of the heterogenous list of columns.

189+

190+- You use `>>>` to compose table creation.

191+

192+> _note_ The compiler will catch any mistype between Schema and

193+> definition; wrong nullability, wrong type, wrong name, etc.

194+

195+---

196+

197+> _note_ You'll also need `OverloadedLabels`, for naming stuff.

198+> This is mostly to avoid having to write manual proxies all

199+> the time and for convenience.

200+

201+---

202+

203+# Setting up the schema

204+

205+- Squeal comes with a very good migration manager, handling _upgrades_ AND

206+_downgrades_.

207+

208+- A migration is a simple type:

209+

210+```haskell

211+Migration io schema0 schema1

212+```

213+

214+- The first parameter is a BaseMonad (typically, IO).

215+

216+- The second parameter is "the current schema of your DB".

217+

218+- The last one is "what you will migrate to".

219+

220+- The `Definition` type used to define upgrade and downgrade functions use the

221+ same logic (from one schema to the other).

222+

223+---

224+

225+# Defining our first migration

226+

227+- We have the setup bit, we need the teardown:

228+

229+```haskell

230+tearDown :: Definition Schema '[]

231+tearDown = dropTable #mp >>> dropTable #groupp

232+```

233+

234+> _note_ GHC will also detect the _proper_ order of what you typed in

235+> downgrade and upgrade should there be any conflict (with foreign keys).

236+

237+```haskell

238+initDB :: Migration IO '[] Schema

239+initDB =

240+ Migration { name = "Schema creation"

241+ , up = void $ define setup

242+ , down = void $ define tearDown }

243+```

244+

245+---

246+

247+# Simple migrator example

248+

249+```haskell

250+main :: IO ()

251+main = do

252+ printSQL setup

253+ void $ withConnection connectionString $

254+ migrateUp $ single initDB

255+```

256+

257+- We print the migration query; you can do this for all queries generated through Squeal.

258+

259+- We use `migrateUp` to perform the migration.

260+

261+- You can run several migration at the same time, to run only one use `single`.

262+

263+---

264+

265+![That was easy](http://gif.eraveline.eu/static/img/0x47f.gif)

266+

267+---

268+

269+# Part II. Insertions

270+

271+---

272+

273+# Manipulations & Queries

274+

275+Besides the specific case of migration, you will mostly perform:

276+

277+- `Manipulation` : inserting, updating and deleting data.

278+

279+- `Query` : fetching data.

280+

281+- Both types are parametric over the same things:

282+

283+ * A schema

284+

285+ * Input parameters

286+

287+ * Output

288+

289+- Simplified, they look like this:

290+

291+```haskell

292+Manipulation schema params columns

293+

294+Query schema params columns

295+```

296+

297+

298+---

299+

300+# Our Haskell model

301+

302+```haskell

303+type Parliament = [Group]

304+

305+data Group =

306+ Group { name :: Text

307+ , members :: [MemberOfParliament] }

308+

309+data MemberOfParliament =

310+ MemberOfParliament { firstName :: Text

311+ , lastName :: Text }

312+```

313+

314+> _note_ We didn't use anything from Squeal.

315+> The model can be entirely separated from the persistence layer.

316+

317+---

318+

319+# Inserting a Parliamentary Group

320+

321+- A group is very simple: it's a uuid and a name. Let's define our params:

322+

323+```haskell

324+type GroupInsertionParams = '[ 'NotNull 'PGuuid

325+ , 'NotNull 'PGtext ]

326+```

327+

328+- Params are not named, but they are indexed. You just need nullability and type.

329+

330+---

331+

332+```haskell

333+groupInsertion :: Manipulation Schema GroupInsertionParams '[]

334+groupInsertion =

335+ insertRow_ #groupp ( Set (param @1) `as` #groupp_id

336+ :* Set (param @2) `as` #name )

337+```

338+

339+---

340+

341+- `TypeApplication` lets us use the index of parameters (counting from 1).

342+

343+- Once again: all this is checked by the compiler. Wrong name, wrong type... you'll get a compile error.

344+

345+- `insertRow_` is a simplified version of `insertRow`. `insertRow` lets you express a `RETURNING` clause and the expected behaviour in case of conflict.

346+

347+---

348+

349+_Inserting a Member of Parliament_

350+# Doing an INSERT INTO ... SELECT

351+

352+- We could create a naive query that takes MP uuid, first name, last name and group uuid...

353+

354+---

355+

356+- But that's boring. So let's use the `INSERT INTO ... SELECT`.

357+

358+---

359+

360+- We will build a query that will return as constants our MP's uuid, first name and last name...

361+

362+---

363+

364+- ... and fetch the uuid of a group given the name of the group.

365+

366+---

367+

368+- There's a `insertQuery` utility function for that. All we have to do is write the `select` !

369+

370+```haskell

371+mpInsertion :: Manipulation Schema MpParams '[]

372+mpInsertion =

373+ insertQuery_ #mp selectGroup -- we just have to write selectGroup !

374+```

375+

376+---

377+

378+_Inserting a Member of Parliament_

379+# The query type

380+

381+- A query looks just like a `Manipulation`:

382+

383+```haskell

384+Query schema params returns

385+```

386+

387+- Returns use a special syntax, that demands names, nullability and types:

388+

389+```haskell

390+type ExampleReturnType = '[ "some_column" ::: 'NotNull 'PGuuid

391+ , "other_column" ::: 'Null 'PGtext ]

392+```

393+

394+- It is not the same as the column definition we used in the schema. That one also expects that you specify, for each column, an eventual default:

395+

396+```haskell

397+type ExampleSchemaCols =

398+ '[ "some_column" ::: 'NoDef :=> 'NotNull 'PGuuid

399+ , "other_column" ::: 'NoDef :=> 'Null 'PGtext ]

400+```

401+

402+---

403+

404+_Inserting a Member of Parliament_

405+# Don't rewrite column definitions

406+

407+- We want our return type to be "all columns from table MP expressed as return type".

408+

409+- But we cannot reuse our neat `MpCols` alias, since the type do not match as we've just seen.

410+

411+- Hopefully, there's a neat Type Family that will let you convert any table you defined to the type of the equivalent row: `TableToRow`.

412+

413+- We finally have the signature for our SELECT query.

414+

415+```haskell

416+selectGroup :: Query Schema MpParams (TableToRow MemberOfParliament)

417+```

418+

419+---

420+

421+_Inserting a Member of Parliament_

422+# Our final Select query

423+

424+- Our intermediate query looks like this:

425+

426+```haskell

427+selectGroup =

428+ select

429+ ( param @1 `as` #mp_id

430+ :* param @2 `as` #first_name

431+ :* param @3 `as` #last_name

432+ :* #groupp ! #groupp_id `as` #mp_group

433+ )

434+ ( from (table #groupp)

435+ & where_ ( #groupp ! #name .== param @4 )

436+ )

437+```

438+

439+- The first three columns are constant defined through our params;

440+

441+- ... we alias the column name using `as`...

442+

443+- ... and when we need the result from the table we use the `#table ! #column` syntax.

444+

445+- We'll go back to the "from" block later.

446+

447+---

448+

449+# Dealing with the connection context

450+

451+- Queries are runned in a connection context:

452+

453+ * When dealing with a single-connection context, use the type `PQ`.

454+

455+ * When dealing with a pool of connection, use the type `PoolPQ`.

456+

457+- Or get rid of the context and use `mtl` style, with the typeclass `MonadPQ`.

458+

459+- We'll use that to demonstrate how to actually run our queries.

460+

461+---

462+

463+# Inserting a whole group

464+

465+```haskell

466+insertGroup :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()

467+insertGroup g@(Group name _) = do

468+ uuid' <- liftBase nextRandom

469+ void $ manipulateParams groupInsertion (uuid', name)

470+ insertMps g

471+```

472+

473+- Remember that we defined a group as a name and a list of MPs.

474+

475+- We are in `MonadBaseControl`, so we cannot use `liftIO`, we need `liftBase`.

476+

477+- To perform a simple insertion, use `manipulateParams`. It takes into parameter

478+instances of `ToParam`, but you will typically use tuples or Generic-SOP.

479+

480+---

481+

482+# Inserting a bunch of MPs

483+

484+```haskell

485+insertMps :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()

486+insertMps (Group groupName mps) =

487+ let tuplify Mp{..} = (, firstName, lastName, groupName) <$> nextRandom

488+ params = traverse tuplify mps

489+ in void $ liftBase params >>= traversePrepared mpInsertion

490+```

491+

492+- This time, we want to do a `preparedStatement`. We'll use `traversePrepare`

493+which behaves like `manipulateParams`, but expect a list of `ToParam`

494+instances.

495+

496+- We build our tuple manually again, mostly because we want to generate UUID on

497+the fly and we don't want to have them in our model.

498+

499+---

500+

501+# Inserting a whole parliament

502+

503+```haskell

504+insertParliament ::

505+ (MonadPQ Schema m, MonadBaseControl IO m) => Parliament -> m ()

506+insertParliament = traverse_ insertGroup

507+```

508+

509+- That's simple enough !

510+

511+- If we want to be a bit safer, though, we can wrap this call in a

512+`transactionally_` function, which will put all that in a transaction.

513+

514+---

515+

516+![Very simple](https://media1.tenor.com/images/0188c63209aced59f1583e1ca94e509e/tenor.gif?itemid=3550689)

517+

518+

519+---

520+

521+# Part III. Selects

522+

523+---

524+

525+# Composable queries

526+

527+- Building basic queries is easy, and is well documented.

528+

529+- However, the real interest of a tool like Squeal is in DRYness, and the documentation is still lacking in "how-to" related to composability.

530+

531+- I'll build an example showing how column selections and from clause can be factorized.

532+

533+- We want to write two queries:

534+

535+ * One to get all members of a specific group.

536+

537+ * One to get all the parliament.

538+

539+---

540+

541+# Decomposing a `Query`

542+

543+- A query typically stars with `select` (variants are available).

544+

545+- It then takes:

546+

547+ * A heterogenous list of fields with a scary signature;

548+

549+ * A virtual table (the from clause and filter clauses), called a `TableExpression`.

550+

551+- And return fields. Ours will look like this:

552+

553+```haskell

554+type GroupRowResult =

555+ '[ "groupName" ::: 'NotNull 'PGtext

556+ , "firstName" ::: 'NotNull 'PGtext

557+ , "lastName" ::: 'NotNull 'PGtext ]

558+```

559+

560+---

561+

562+# The Table Expression

563+

564+- It necessarily contains a `fromClause` (table, view or subquery, plus optional joins).

565+

566+- You can add where, groups, "HAVING" clause, order, etc.

567+

568+- `from` creates a basic `TableExpression` that you extend through various function to add clauses.

569+

570+- For our queries, we will share a common `FromClause`.

571+

572+---

573+

574+# The From Clause

575+

576+```

577+FromClause schema params from

578+```

579+

580+- We need Schema, input parameters and a `FromType` giving the available fields of the expression.

581+

582+- In our case, we'll join the table `mp` and the table `groupp`, meaning the `from` will be all fields of these tables.

583+

584+- We can use `TableToRow` to be more DRY:

585+

586+```haskell

587+type BaseParliamentSelection =

588+ '[ "g" ::: TableToRow GroupCols

589+ , "m" ::: TableToRow MpCols ]

590+```

591+

592+> _note_ We've also put everything with table aliases: "g" and "m".

593+

594+---

595+

596+# Writing our from clause

597+

598+```haskell

599+baseParliamentTables ::

600+ FromClause Schema (param :: [NullityType]) BaseParliamentSelection

601+baseParliamentTables =

602+ table

603+ (#groupp `as` #g)

604+ & innerJoin

605+ (table (#mp `as` #m))

606+ (#m ! #mp_group .== #g ! #groupp_id)

607+```

608+

609+- When picking "from" something, you need to specify the type with a function: `table` for a table, `view` for a view, etc.

610+

611+- All joins are available. `innerJoin` is the most basic one. It takes the joined table and the joining condition.

612+

613+- We have to specifiy the type of `param` (current limitation of the lib), even though _any_ params will be compatible with this, so we can plug `where` clauses depending on params should we need to !

614+

615+---

616+

617+# Typing the common selection

618+

619+- Both our querie will need the same fields. This has to be factorized too.

620+

621+- The scary signature of selection fields:

622+

623+```haskell

624+NP (Aliased (Expression schema from grouping params)) cols

625+```

626+

627+- `NP` is for heterogenous lists ("n-ary product").

628+

629+- `from` is the virtual table type, so our `BaseParliamentSelection`.

630+

631+- `grouping` is there to make a distinction between aggregated / unaggregated queries.

632+

633+- And finally, cols is the return type.

634+

635+---

636+

637+# Our common selection

638+

639+```haskell

640+groupSelection ::

641+ NP (Aliased (Expression Schema BaseParliamentSelection 'Ungrouped param))

642+ GroupRowResult

643+groupSelection =

644+ #g ! #name `as` #groupName

645+ :* #m ! #first_name `as` #firstName

646+ :* #m ! #last_name `as` #lastName

647+```

648+

649+- I hope you like big signatures.

650+

651+- But it's what let GHC checks that all alias and columns are available.

652+

653+- And that you're returning what you really intend to return.

654+

655+---

656+

657+# Putting it all together

658+

659+```haskell

660+selectParliament :: Query Schema '[] GroupRowResult

661+selectParliament =

662+ select groupSelection (from baseParliamentTables)

663+```

664+

665+```haskell

666+selectGroupMembers :: Query Schema '[ 'NotNull 'PGtext] GroupRowResult

667+selectGroupMembers =

668+ select groupSelection

669+ (from baseParliamentTables

670+ & where_ (#g ! #name .== param @1))

671+```

672+

673+- That is fairly DRY. And _entirely typesafe_.

674+

675+---

676+

677+# Actually fetching the data

678+

679+- We'll build an intermediary datatype representing our rows.

680+

681+- We'll make it match our row.

682+

683+- And we'll add generic-SOP so that we can build them from query results.

684+

685+```haskell

686+type GroupRowResult =

687+ '[ "groupName" ::: 'NotNull 'PGtext

688+ , "firstName" ::: 'NotNull 'PGtext

689+ , "lastName" ::: 'NotNull 'PGtext ]

690+```

691+

692+```haskell

693+data GroupRow =

694+ GroupRow { groupName :: Text

695+ , firstName :: Text

696+ , lastName :: Text }

697+ deriving (Generic)

698+

699+instance SOP.Generic GroupRow

700+instance SOP.HasDatatypeInfo GroupRow

701+```

702+

703+---

704+

705+# Aggregate result logic

706+

707+- We will get tabular, SQL data.

708+

709+- Our results will be `[GroupRow]`.

710+

711+- We'll build `Groups` from this:

712+

713+```haskell

714+buildGroup :: NE.NonEmpty GroupRow -> Group

715+buildGroup grs =

716+ let buildMP (GroupRow _ f l) = Mp f l

717+ name = groupName . NE.head $ grs

718+ members = NE.toList (buildMP <$> grs)

719+ in Group{..}

720+

721+rowToGroups :: [GroupRow] -> [Group]

722+rowToGroups =

723+ let grouped = fmap NE.fromList . L.groupBy ((==) `on` groupName)

724+ in fmap buildGroup . grouped

725+```

726+

727+---

728+

729+# Finally calling our queries

730+

731+- Query with params will use `runQueryParams`.

732+

733+- Query without params will use `runQuery`.

734+

735+- Result is inside a `MonadPQ` and of type `K` from generic-sop.

736+

737+- You get your actual result using `getRows`. Exemple:

738+

739+```haskell

740+getParliament :: (MonadPQ Schema m, MonadBaseControl IO m) => m [Group]

741+getParliament = do

742+ res <- runQuery selectParliament

743+ rows <- getRows res

744+ pure $ rowToGroups rows

745+```

746+

747+- In real life of course you'll write:

748+

749+```haskell

750+getParliament =

751+ rowToGroups <$> (runQuery selectParliament >>= getRows)

752+```

753+

754+---

755+

756+# Our query with params

757+

758+```haskell

759+getGroupMembers ::

760+ (MonadPQ Schema m, MonadBaseControl IO m) => Text -> m (Maybe Group)

761+getGroupMembers =

762+ listToMaybe . rowToGroups <$>

763+ (runQueryParams selectGroupMembers (Only t) >>= getRows)

764+```

765+

766+- And that's it.

767+

768+---

769+

770+![Eazy](https://media.tenor.com/images/8fc7c4077efe11b4a3a3b9ae4e643e87/tenor.gif)

771+

772+---

773+

774+# Conclusion

775+

776+---

777+

778+# Pros & Cons

779+

780+- Not everything is included: some cool stuff like array_agg and window functions are not available yet.

781+

782+- But development is _very_ active. `IN` clauses were missing but were added in the 4.0 released recently.

783+

784+- It's bleeding edge. You need latest LTS to be comfortable and psql >= 9.5.

785+

786+- It's Postgres-only but I would say that's a feature. Multi-DB tools are even more complex.

787+

788+- The author & maintainer is <3.

789+

790+- Typesafe. 'nuff said.

791+

792+---

793+

794+# Thank you !

stack.yaml+6−1

@@ -1,3 +1,8 @@

1−resolver: nightly-2018-09-03

1+resolver: nightly-2019-07-14

22packages:

33- squeal-postgresql

5+extra-deps:

6+- unliftio-pool-0.2.1.0

7+- github: morphismtech/free-categories

8+ commit: c0e555fbefb5c21619e532264c4dfeac556d0630