dev..5b9374f · squeal · git.iko.soy

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.circleci/config.yml+2−3

since splitsnapshots

unifiedsplit

@@ -2,10 +2,9 @@ version: 2

2jobs:

3 build:

4 docker:

5− - image: haskell:8.6.5

5+ - image: haskell:latest

6 - image: circleci/postgres:latest

7 environment:

8− POSTGRES_USER: root

9 POSTGRES_DB: exampledb

8 POSTGRES_DB: exampledb

10 steps:

9 steps:

11 - checkout

10 - checkout

@@ -14,7 +13,7 @@ jobs:

14 - dependency-cache

13 - dependency-cache

15 - run: apt-get update && apt-get install -y libpq-dev xz-utils make

14 - run: apt-get update && apt-get install -y libpq-dev xz-utils make

16 - run: stack upgrade && stack update

15 - run: stack upgrade && stack update

17− - run: stack build --fast

16+ - run: stack build

18 - run: stack test

17 - run: stack test

19 - run: stack haddock

18 - run: stack haddock

20 - save_cache:

19 - save_cache:

README.md+119−126

@@ -44,13 +44,6 @@ composable and cover a large portion of SQL.

44* linear, invertible migrations

45* connection pools

46* transactions

47−* views

48−* array, composite and enumerated types

49−* json functions and operations

50−* multischema support

51−* correlated subqueries

52−* window functions

53−* text search

55## installation

48## installation

@@ -58,16 +51,10 @@ composable and cover a large portion of SQL.

59## testing

52## testing

61−Start postgres on localhost port `5432` and create a database named `exampledb`.

54+start postgres on localhost port `5432` and create a database named `exampledb`.

63`stack test`

56`stack test`

65−## contributing

66−

67−We welcome contributors.

68−Please make pull requests on the `dev` branch instead of `master`.

69−The `Issues` page is a good place to communicate.

70−

71## usage

58## usage

73Let's see an example!

60Let's see an example!

@@ -75,15 +62,16 @@ Let's see an example!

75First, we need some language extensions because Squeal uses modern GHC

62First, we need some language extensions because Squeal uses modern GHC

76features.

63features.

78−```Haskell

65+```haskell

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

66+>>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels

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

67+>>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators

81```

68```

83We'll need some imports.

70We'll need some imports.

85−```Haskell

72+```haskell

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

73+>>> import Control.Monad (void)

74+>>> import Control.Monad.Base (liftBase)

87>>> import Data.Int (Int32)

75>>> import Data.Int (Int32)

88>>> import Data.Text (Text)

76>>> import Data.Text (Text)

89>>> import Squeal.PostgreSQL

77>>> import Squeal.PostgreSQL

@@ -91,7 +79,7 @@ We'll need some imports.

92We'll use generics to easily convert between Haskell and PostgreSQL values.

80We'll use generics to easily convert between Haskell and PostgreSQL values.

94−```Haskell

82+```haskell

95>>> import qualified Generics.SOP as SOP

83>>> import qualified Generics.SOP as SOP

96>>> import qualified GHC.Generics as GHC

84>>> import qualified GHC.Generics as GHC

97```

85```

@@ -99,152 +87,155 @@ We'll use generics to easily convert between Haskell and PostgreSQL values.

99The first step is to define the schema of our database. This is where

87The first step is to define the schema of our database. This is where

100we use `DataKinds` and `TypeOperators`.

88we use `DataKinds` and `TypeOperators`.

101

102−```Haskell

90+```haskell

103>>> :{

91>>> :{

104−type UsersColumns =

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

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

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

108−type EmailsColumns =

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

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

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

112−type EmailsConstraints =

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

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

115type Schema =

92type Schema =

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

93+ '[ "users" :::

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

94+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

118−type Schemas = Public Schema

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

96+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

97+ ]

98+ , "emails" :::

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

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

101+ ] :=>

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

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

104+ , "email" ::: 'NoDef :=> 'Null 'PGtext

105+ ]

106+ ]

119:}

107:}

120```

108```

121

109

122−Notice the use of type operators.

110+Notice the use of type operators. `:::` is used

123−

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

111+to pair an alias `Symbol` with either a `TableType` or a `ColumnType`.

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

112+`:=>` is used to pair a `TableConstraint`s with a `ColumnsType`,

126−operator.

127−

128−`:=>` is used to pair `TableConstraints` with a `ColumnsType`,

129yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

113yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

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

114+yielding a `ColumnType`.

131

115

132Next, we'll write `Definition`s to set up and tear down the schema. In

116Next, we'll write `Definition`s to set up and tear down the schema. In

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

117+Squeal, a `Definition` is a `createTable`, `alterTable` or `dropTable`

134−has two type parameters, corresponding to the schema

118+command and has two type parameters, corresponding to the schema

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

119+before being run and the schema after. We can compose definitions using

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

120+`>>>`. Here and in the rest of our commands we make use of overloaded

137labels to refer to named tables and columns in our schema.

121labels to refer to named tables and columns in our schema.

138

122

139−```Haskell

123+```haskell

140>>> :{

124>>> :{

141let

125let

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

126+ setup :: Definition '[] Schema

143− setup =

127+ setup =

144− createTable #users

128+ createTable #users

145− ( serial `as` #id :*

129+ ( serial `As` #id :*

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

130+ (text & notNull) `As` #name :* Nil )

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

131+ ( primaryKey #id `As` #pk_users :* Nil ) >>>

148− createTable #emails

132+ createTable #emails

149− ( serial `as` #id :*

133+ ( serial `As` #id :*

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

134+ (int & notNull) `As` #user_id :*

151− (text & nullable) `as` #email )

135+ (text & null_) `As` #email :* Nil )

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

136+ ( primaryKey #id `As` #pk_emails :*

153− foreignKey #user_id #users #id

137+ foreignKey #user_id #users #id

154− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

138+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )

155:}

139:}

156```

140```

157

141

158−We can easily see the generated SQL is unsurprising looking.

142+We can easily see the generated SQL is unsuprising looking.

159

143

160−```Haskell

144+```haskell

161−>>> printSQL setup

145+>>> renderDefinition setup

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

163−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);

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

164```

147```

165

148

166Notice that `setup` starts with an empty schema `'[]` and produces `Schema`.

149Notice that `setup` starts with an empty schema `'[]` and produces `Schema`.

167In our `createTable` commands we included `TableConstraint`s to define

150In our `createTable` commands we included `TableConstraint`s to define

168−primary and foreign keys, making them somewhat complex. Our `teardown`

151+primary and foreign keys, making them somewhat complex. Our tear down

169`Definition` is simpler.

152`Definition` is simpler.

170

153

171−```Haskell

154+```haskell

172>>> :{

155>>> :{

173let

156let

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

157+ teardown :: Definition Schema '[]

175 teardown = dropTable #emails >>> dropTable #users

158 teardown = dropTable #emails >>> dropTable #users

176:}

159:}

177−

178−>>> printSQL teardown

160+>>> renderDefinition teardown

179−DROP TABLE "emails";

161+"DROP TABLE emails; DROP TABLE users;"

180−DROP TABLE "users";

181−```

182−

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```

162```

191

163

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

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

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

165+A `Manipulation` is an `insertRow` (or other inserts), `update`

166+or `deleteFrom` command and

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

167+has three type parameters, the schema it refers to, a list of parameters

195−and an output row. When

168+it can take as input, and a list of columns it produces as output. When

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

169we insert into the users table, we will need a parameter for the `name`

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

170+field but not for the `id` field. Since it's optional, we can use a default

198value. However, since the emails table refers to the users table, we will

171value. However, since the emails table refers to the users table, we will

199need to retrieve the user id that the insert generates and insert it into

172need to retrieve the user id that the insert generates and insert it into

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

173+the emails table. Take a careful look at the type and definition of both

201−`with` statement.

174+of our inserts.

202

175

203−```Haskell

176+```haskell

204>>> :{

177>>> :{

205let

178let

206− insertUser :: Manipulation_ Schemas User ()

179+ insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]

207− insertUser = with (u `as` #u) e

180+ insertUser = insertRow #users

208− where

209− u = insertInto #users

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

181+ (Default `As` #id :* Set (param @1) `As` #name :* Nil)

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

182+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))

212− e = insertInto_ #emails $ Select

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

214− (from (common #u))

215:}

183:}

216−

184+>>> :{

185+let

186+ insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

187+ insertEmail = insertRow #emails

188+ ( Default `As` #id :*

189+ Set (param @1) `As` #user_id :*

190+ Set (param @2) `As` #email :* Nil )

191+ OnConflictDoNothing (Returning Nil)

192+:}

217−>>> printSQL insertUser

193+>>> renderManipulation insertUser

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

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

195+>>> renderManipulation insertEmail

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

219```

197```

220

198

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

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

222interested in the ids here, just the usernames and email addresses. We

200interested in the ids here, just the usernames and email addresses. We

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

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

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

202+`Manipulation` with the same kind of type parameters.

225

203

226−```Haskell

204+```haskell

227>>> :{

205>>> :{

228let

206let

229− getUsers :: Query_ Schemas () User

207+ getUsers :: Query Schema '[]

208+ '[ "userName" ::: 'NotNull 'PGtext

209+ , "userEmail" ::: 'Null 'PGtext ]

230− getUsers = select_

210+ getUsers = select

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

211+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* Nil)

232− ( from (table (#users `as` #u)

212+ ( from (table (#users `As` #u)

233− & innerJoin (table (#emails `as` #e))

213+ & innerJoin (table (#emails `As` #e))

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

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

235:}

215:}

216+>>> renderQuery getUsers

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

218+```

219+

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

221+for users. We give the type `Generics.SOP.Generic` and

222+`Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows

223+we receive when we run `getUsers`. Notice that the record fields of the

224+`User` type match the column names of `getUsers`.

236

225

237−>>> printSQL getUsers

226+```haskell

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

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

228+>>> instance SOP.Generic User

229+>>> instance SOP.HasDatatypeInfo User

239```

230```

240

231

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

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

242

233

243−```Haskell

234+```haskell

244>>> :{

235>>> :{

245let

236let

246 users :: [User]

237 users :: [User]

247− users =

238+ users =

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

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

249 , User "Bob" Nothing

240 , User "Bob" Nothing

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

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

@@ -260,21 +251,23 @@ the changing schema information through by using the indexed `PQ` monad

260transformer and when the schema doesn't change we can use `Monad` and

251transformer and when the schema doesn't change we can use `Monad` and

261`MonadPQ` functionality.

252`MonadPQ` functionality.

262

253

263−```Haskell

254+```haskell

264>>> :{

255>>> :{

265let

256let

266− session :: PQ Schemas Schemas IO ()

257+ session :: PQ Schema Schema IO ()

267 session = do

258 session = do

268− _ <- traversePrepared_ insertUser users

259+ idResults <- traversePrepared insertUser (Only . userName <$> users)

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

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

269 usersResult <- runQuery getUsers

262 usersResult <- runQuery getUsers

270 usersRows <- getRows usersResult

263 usersRows <- getRows usersResult

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

264+ liftBase $ print (usersRows :: [User])

272−in

265+:}

266+>>> :{

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

267+void . withConnection "host=localhost port=5432 dbname=exampledb" $

274− define setup

268+ define setup

275− & pqThen session

269+ & pqThen session

276− & pqThen (define teardown)

270+ & pqThen (define teardown)

277:}

271:}

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

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

279−-}

280```

273```

RELEASE NOTES.md−1077

@@ -1,1082 +1,5 @@

1## RELEASE NOTES

3−### Version 0.5

4−

5−Version 0.5 makes a number of large changes and additions to Squeal.

6−I want to thank folks who contributed issues and pull requests;

7−Raveline, rimmington, ilyakooo0, chshersh, reygoch, and more.

8−

9−**Multi-schema support**

10−

11−Previous versions of Squeal only supported definitions in the "public"

12−schema. Squeal 0.5 adds support for multiple schemas with the new kind

13−

14−```Haskell

15−type SchemasType = [(Symbol,SchemaType)]

16−```

17−

18−In order to upgrade your queries, manipulations and definitions from

19−Squeal 0.4, you will have to apply the `Public` type family, which indicates

20−that your only schema is the "public" schema.

21−

22−```Haskell

23−-- Squeal 0.4

24−setup :: Definition '[] Schema

25−

26−-- Squeal 0.5

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

28−```

29−

30−You can create non-public schemas using `createSchema` and inversely

31−remove them using `dropSchema`. There is also an idempotent

32−`createSchemaIfNotExists`.

33−

34−In order to handle aliases which may refer to non-public schemas, Squeal 0.5

35−introduces `QualifiedAlias`es. A `QualifiedAlias` can be referred to using

36−the `(!)` operator from the `IsQualified` typeclass; but if you want to refer

37−to an alias from the "public" schema, you can continue to use a single

38−overloaded label, no need to write `#public ! #tab`, just write `#tab`.

39−

40−**Top-level statements**

41−

42−As a consequence of multi-schema support, common table expressions that

43−a `Query` or `Manipulation` may refer to had to be broken into a new parameter.

44−Additionally, `Query` gained another new parameter for its outer scope which

45−will be discussed in the next section.

46−

47−To simplify type signatures that you have to write for top-level queries

48−and manipulations, Squeal 0.5 introduces the `Query_` and `Manipulation_`

49−type families.

50−

51−```

52−type family Query_

53− (schemas :: SchemasType)

54− (parameters :: Type)

55− (row :: Type) where

56− Query_ schemas params row =

57− Query '[] '[] schemas (TuplePG params) (RowPG row)

58−```

59−

60−As you see, a top-level `Query_` has no outer scope and no common

61−table expressions in scope, they are empty `'[]`. Moreover,

62−its parameters and row parameters are now `Type`s, which are

63−converted to corresponding Postgres types using the `TuplePG`

64−and `RowPG` type families. This means you can write the type signatures

65−for your top-level statements using the Haskell types that you

66−intend to input and retrieve when running the statements. Similar

67−to `Query_`, there is a `Manipulation_` type, the only difference

68−being that a general `Manipulation` doesn't have an outer scope,

69−only a scope for common table expressions.

70−

71−**Subquery expressions**

72−

73−Previous versions of Squeal offered subquery expression support

74−but there were issues. The common use case of using the `IN` operator

75−from SQL was overly complex. There was a proliferation of subquery

76−functions to handle different comparison operators, each with two versions

77−for comparing `ALL` or `ANY` of the query rows. And, most confoundedly,

78−there was no way to support the `EXISTS` subquery because the "outer scope"

79−for a query was not available.

80−

81−Squeal adds an outer scope to the `Query` type.

82−

83−```Haskell

84−newtype Query

85− (outer :: FromType)

86− (commons :: FromType)

87− (schemas :: SchemasType)

88− (params :: [NullityType])

89− (row :: RowType)

90− = UnsafeQuery { renderQuery :: ByteString }

91−```

92−

93−This enables a well-typed `exists` function.

94−

95−```Haskell

96−exists

97− :: Query (Join outer from) commons schemas params row

98− -> Condition outer commons grp schemas params from

99−```

100−

101−The `in_` and `notIn` functions were simplified to handle the most

102−common use case of comparing to a list of values.

103−

104−```Haskell

105−in_

106− :: Expression outer commons grp schemas params from ty -- ^ expression

107− -> [Expression outer commons grp schemas params from ty]

108− -> Condition outer commons grp schemas params from

109−```

110−

111−Finally, general subquery comparisons were abstracted to work with

112−any comparison operators, using the `Operator` type which will be discussed in

113−the next section.

114−

115−```Haskell

116−subAll

117− :: Expression outer commons grp schemas params from ty1

118− -> Operator ty1 ty2 ('Null 'PGbool)

119− -> Query (Join outer from) commons schemas params '[col ::: ty2]

120− -> Condition outer commons grp schemas params from

121−

122−subAny

123− :: Expression outer commons grp schemas params from ty1

124− -> Operator ty1 ty2 ('Null 'PGbool)

125− -> Query (Join outer from) commons schemas params '[col ::: ty2]

126− -> Condition outer commons grp schemas params from

127−```

128−

129−**Expression RankNTypes**

130−

131−Squeal 0.5 introduces RankNType type synonyms for common expression patterns.

132−The simplest example is the `Expr` type, a type for "closed" expressions

133−that cannot reference any aliases or parameters.

134−

135−```Haskell

136−type Expr x

137− = forall outer commons grp schemas params from

138− . Expression outer commons grp schemas params from x

139−```

140−

141−There is also a function type `(-->)`, which is a subtype of the usual Haskell function

142−type `(->)`.

143−

144−```Haskell

145−type (-->) x y

146− = forall outer commons grp schemas params from

147− . Expression outer commons grp schemas params from x

148− -> Expression outer commons grp schemas params from y

149−```

150−

151−We saw in the subquery section that there is an `Operator` type.

152−

153−```Haskell

154−type Operator x1 x2 y

155− = forall outer commons grp schemas params from

156− . Expression outer commons grp schemas params from x1

157− -> Expression outer commons grp schemas params from x2

158− -> Expression outer commons grp schemas params from y

159−```

160−

161−There are also types `FunctionN` and `FunctionVar` for n-ary functions

162−and variadic functions.

163−

164−```

165−type FunctionN xs y

166− = forall outer commons grp schemas params from

167− . NP (Expression outer commons grp schemas params from) xs

168− -> Expression outer commons grp schemas params from y

169−```

170−

171−An n-ary function takes an `NP` list of `Expression`s as its argument.

172−Squeal 0.5 adds a helpful operator `(*:)`, to help scrap your `Nil`s.

173−You can construct an `NP` list now by using the operator `(:*)`,

174−until your last element, using `(*:)` there. For instance, the function

175−`atan2_` takes two arguments, `atan2_ (pi *: 2)`.

176−

177−**Selections**

178−

179−Previously, Squeal provided a couple versions of `SELECT` depending

180−on whether you wanted to select all columns of a unique table

181−in the from clause, i.e. `*`, all columns of a particular table

182−in the from clause, i.e. `.*`, or a list of columns from the from clause.

183−

184−Squeal 0.5 refactors this pattern into a `Selection` GADT type, allowing

185−for abstraction and combinations that were not possible before.

186−

187−```Haskell

188−data Selection outer commons grp schemas params from row where

189− Star

190− :: HasUnique tab from row

191− => Selection outer commons 'Ungrouped schemas params from row

192− DotStar

193− :: Has tab from row

194− => Alias tab

195− -> Selection outer commons 'Ungrouped schemas params from row

196− List

197− :: SListI row

198− => NP (Aliased (Expression outer commons grp schemas params from)) row

199− -> Selection outer commons grp schemas params from row

200− Over

201− :: SListI row

202− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row

203− -> WindowDefinition outer commons grp schemas params from

204− -> Selection outer commons grp schemas params from row

205− Also

206− :: Selection outer commons grp schemas params from right

207− -> Selection outer commons grp schemas params from left

208− -> Selection outer commons grp schemas params from (Join left right)

209−```

210−

211−In addition to the `Star`, `DotStar` and `List` constructors, there is an

212−`Also` constructor combinator, which enables users to combine `Selection`s.

213−Additionally, there is an `Over` constructor that is used to enable

214−window functions, described in the next section.

215−

216−To upgrade from Squeal 0.4, you will replace `selectStar` with `select Star`,

217−replace `selectDotStar #tab` with `select (DotStar #tab)`. The `List`

218−selection is such a common use case that there is a function `select_` which

219−automatically applies it, so to upgrade from Squeal 0.4, replace `select`

220−with `select_`. There are also independent `selectDistinct` and `selectDistinct_`

221−functions to filter out duplicate rows.

222−

223−**Query clauses**

224−

225−Previously, Squeal provided a couple versions of `INSERT` depending

226−on whether you wanted to insert `VALUES` or a query.

227−

228−Squeal 0.5 refactors this pattern into a `QueryClause` GADT.

229−

230−```

231−-- Squeal 0.4

232−insertRow_ #tab (Set 2 `as` #col1 :* Default `as` #col2)

233−insertQuery_ #tab (selectStar (from (table #other_tab)))

234−

235−-- Squeal 0.5

236−insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))

237−insertInto_ #tab (Subquery (select Star (from (table #other_tab))))

238−```

239−

240−**Window functions and aggregation**

241−

242−Previous versions of Squeal provided no support for window functions.

243−Squeal 0.5 adds support for window functions. We saw `Over` in the

244−previous section.

245−

246−```Haskell

247−Over

248− :: SListI row

249− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row

250− -> WindowDefinition outer commons grp schemas params from

251− -> Selection outer commons grp schemas params from row

252−```

253−

254−`Over` combines window functions with window definitions. A `WindowDefinition`

255−is constructed using the `partitionBy` function, optionally with an `orderBy`

256−clause. For example,

257−

258−```Haskell

259−query :: Query_ (Public Schema) () (Row Int32 Int32)

260−query = select

261− (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))

262− (from (table #tab))

263−```

264−

265−Here the `rank` function is a `WindowFunction`

266−

267−```Haskell

268−rank :: WinFun0 ('NotNull 'PGint8)

269−rank = UnsafeWindowFunction "rank()"

270−```

271−

272−`WinFun0` is a RankNType, like `Expr` was, used for no argument window functions.

273−Similarly, there are also `WinFun1` and `WinFunN` types for

274−window functions and n-ary window functions.

275−

276−In order to use the same syntax for certain window functions and aggregate functions,

277−a new typeclass `Aggregate` was introduced. So for instance, `sum_` can be

278−either a `Distinction` `Expression` or a `WindowFunction`, used either with

279−a `groupBy` or with a `partitionBy` in the appropriate way.

280−

281−```

282−data Distinction (expr :: kind -> Type) (ty :: kind)

283− = All (expr ty)

284− | Distinct (expr ty)

285−```

286−

287−Aggregate functions can be run over all rows or only over distinct rows,

288−while window functions bear no such distinction.

289−

290−**Migrations**

291−

292−Thanks to [https://github.com/Raveline](Raveline) Squeal 0.5 introduces

293−a function `defaultMain` to easily create a command line program to

294−run or rewind your migrations.

295−

296−Previously, Squeal's migrations were impure, allowing in addition to

297−running `Definition`s to run arbitrary `IO` operations, such as inserting

298−data into the database or printing out status messages. In order to

299−provide compatibility with other migration systems, Squeal 0.5 introduces

300−pure migrations, that is migrations that are only `Definition`s.

301−

302−```Haskell

303−data Migration p schemas0 schemas1 = Migration

304− { name :: Text -- ^ The `name` of a `Migration`.

305− -- Each `name` in a `Migration` should be unique.

306− , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.

307− , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.

308− } deriving (GHC.Generic)

309−```

310−

311−A pure migration is a `Migration Definition`, a pair of inverse

312−`Definition`s with a unique name. To recover impure migrations, Squeal 0.5

313−introduces the `Terminally` type.

314−

315−```Haskell

316−newtype Terminally trans monad x0 x1 = Terminally

317− { runTerminally :: trans x0 x1 monad () }

318−```

319−

320−`Terminally` applies the indexed monad transformer and the monad it transforms

321−to the unit type `()`, thereby turning an indexed monad into a `Category`. An

322−impure migration is a `Migration (Terminally PQ IO)`. You can always cast

323−a pure migration into an impure migration with the functor, `pureMigration`.

324−

325−```Haskell

326−pureMigration

327− :: Migration Definition schemas0 schemas1

328− -> Migration (Terminally PQ IO) schemas0 schemas1

329−```

330−

331−To run either pure or impure migrations, Squeal 0.5 introduces

332−a typeclass, `Migratory`.

333−

334−```

335−class Category p => Migratory p where

336−

337− migrateUp

338− :: AlignedList (Migration p) schemas0 schemas1

339− -> PQ schemas0 schemas1 IO ()

340−

341− migrateDown

342− :: AlignedList (Migration p) schemas0 schemas1

343− -> PQ schemas1 schemas0 IO ()

344−```

345−

346−The signatures of `migrateUp` and `migrateDown` have been changed

347−to make them easier to compose with other `PQ` actions.

348−

349−**Transactions**

350−

351−You can now run transactions `ephemerally`, guaranteed to roll back,

352−but return the result or throw the exception that the transaction

353−would have generated. This is useful for testing. You can also

354−`transactionallyRetry` computations, retrying the transaction if

355−a [serialization failure](https://www.postgresql.org/docs/11/transaction-iso.html#XACT-REPEATABLE-READ) occurs.

356−

357−**Types**

358−

359−Squeal now supports money via a `Money` Haskell `Type` and a `'PGmoney`

360−`PGType`. Squeal 0.5 also adds support for creating domain types

361−with `createDomain`.

362−

363−**Time**

364−

365−Squeal 0.5 adds support for new functions; `now`, `makeDate`, `makeTime`,

366−, `makeTimestamp`, and `makeTimestamptz`, a function `interval_` for

367−constructing time intervals out multiples of `TimeUnit`s, and a new

368−`TimeOp` class, defining affine space operators for time types and their

369−differences.

370−

371−**Literals**

372−

373−Squeal allows you to include Haskell values in your statements using

374−out of line `parameter`s, but often you want to include them inline,

375−as a SQL `literal`. Squeal 0.5 enables this using the `Literal` class.

376−

377−**Set returning functions**

378−

379−Squeal 0.5 adds support for set returning functions such as `unnest`,

380−with the `RankNType` `SetOfFunction`, which can be used as as a `FromClause`.

381−

382−**Text search**

383−

384−Squeal 0.5 adds extensive support for text search types, functions and operators.

385−

386−**Much more**

387−

388−Lots more changes went into and under the hood of the new version.

389−The `Expression` module was split into coherent submodules since it

390−had grown to immense proportions. New modules `Alias`, `PG` and `List`

391−were added to relieve some of the burden that the `Schema` module

392−had been carrying. Rendering has been better unified with a new

393−`RenderSQL` typeclass. Type level list concatenation with the `Additional`

394−typeclass has been added. `Manipulation`s `update` and `delete`

395−were upgraded, so you can leave out fields you don't want to update and

396−use `USING` clauses in deletes. Upserts which were previously broken

397−now work. The `IO` typeclass hierarchy was changed from `MonadBase`

398−and `MonadBaseControl` to `MonadIO` and `MonadUnliftIO`. A new

399−`withRecursive` `Manipulation` was added. `SquealException`s were

400−refactored and a `trySqueal` function added. Arrays were refactored.

401−And there was probably more I've forgotten.

402−

403−### Version 0.4

404−

405−Version 0.4 strengthens Squeal's type system, adds

406−support for multidimensional arrays, improves support

407−for container type, improves `with` statements,

408−improves runtime exceptions, accomodates SQL's three-valued logic,

409−adds subquery expressions, and adds table and view type expressions.

410−

411−**Types**

412−

413−Squeal 0.4 renames some kinds to aid intuition:

414−

415−```Haskell

416−type RowType = [(Symbol, NullityType)] -- previously RelationType

417−type FromType = [(Symbol, RowType)] -- previously RelationsType

418−```

419−

420−Null safety for array and composite types is gained by having the base

421−type of an array be a `NullityType` and the base type of a composite

422−a `RowType`.

423−

424−```Haskell

425−data PGType

426− = ..

427− | PGvararray NullityType

428− | PGfixarray Nat NullityType

429− | PGcomposite RowType

430−```

431−

432−Squeal embeds Postgres types into Haskell using data kinds and type-in-type:

433−

434−```Haskell

435−data PGType = PGbool | ..

436−data NullityType = Null PGType | NotNull PGType

437−type RowType = [(Symbol, NullityType)] -- previously RelationType

438−type FromType = [(Symbol, RowType)] -- previously RelationsType

439−```

440−

441−In another sense, we can embed Haskell types

442−into Postgres types by providing type families:

443−

444−```Haskell

445−type family PG (hask :: Type) :: PGType

446−type family NullPG (hask :: Type) :: NullityType

447−type family TuplePG (hask :: Type) :: [NullityType]

448−type family RowPG (hask :: Type) :: RowType

449−```

450−

451−Let's look at these one by one.

452−

453−`PG` was introduced in Squeal 0.3. It was a closed type family that

454−associates some Haskell types to their obvious corresponding Postgres

455−types like `PG Double = 'PGfloat8`. It only worked on base types,

456−no arrays or composites. Squeal 0.4 extends it to

457−such container types and makes it an open type family so that

458−users can make their own type instances.

459−

460−`NullPG` had a different name before but it does the obvious

461−thing for Haskell with `Maybe`s:

462−

463−```Haskell

464−type family NullPG hask where

465− NullPG (Maybe hask) = 'Null (PG hask)

466− NullPG hask = 'NotNull (PG hask)

467−```

468−

469−`TuplePG` uses generics to turn tuple types (including records)

470−into lists of `NullityType`s in the logical way, e.g.

471−`TuplePG (Bool, Day) = '[ 'PGbool, 'PGdate]`.

472−

473−`RowPG` also uses generics to turn record types into a `RowType` in the logical way, e.g.

474−

475−```Haskell

476−>>> data Person = Person { name :: Text, age :: Int32 } deriving GHC.Generic

477−>>> instance SOP.Generic Person

478−>>> instance SOP.HasDatatypeInfo Person

479−>>> :kind! TuplePG Person

480−TuplePG Person :: [NullityType]

481−= '['NotNull 'PGtext, 'NotNull 'PGint4]

482−>>> :kind! RowPG Person

483−RowPG Person :: [(Symbol, NullityType)]

484−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

485−```

486−

487−We've already seen a hint of why these types are useful in one construction

488−from Squeal 0.3. Creating composite types in Postgres directly from a Haskell

489−record type essentially uses `RowPG`. Another important use is in simplifying

490−the type signatures for a `Query` or `Manipulation`. Very often, you will have

491−a tuple type corresponding to the parameters and a record type corresponding

492−to the returned columns of a `Query` or `Manipulation`. Instead of writing

493−boilerplate signature you can reuse these with the help of `TuplePG` and `RowPG`

494−

495−For instance:

496−

497−```Haskell

498−>>> :{

499−let

500− query :: Query '["user" ::: 'View (RowPG Person)] (TuplePG (Only Int32)) (RowPG Person)

501− query = selectStar (from (view #user) & where_ (#age .> param @1))

502−:}

503−```

504−

505−**Arrays**

506−

507−In addition to being able to encode and decode basic Haskell types

508−like `Int16` and `Text`, Squeal 0.4 permits you to encode and decode Haskell types to

509−Postgres array types. The `Vector` type corresponds to to variable length arrays.

510−And thanks to an idea from [Mike Ledger](https://github.com/mikeplus64),

511−homogeneous tuples correspond to fixed length arrays. We can even

512−create multi-dimensional fixed length arrays. Let's see an example.

513−

514−```Haskell

515−>>> :{

516−data Row = Row

517− { col1 :: Vector Int16

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

519− , col3 :: ((Int16,Int16),(Int16,Int16),(Int16,Int16))

520− } deriving (Eq, GHC.Generic)

521−:}

522−

523−>>> instance Generic Row

524−>>> instance HasDatatypeInfo Row

525−```

526−

527−Define a simple round trip query.

528−

529−```Haskell

530−>>> :{

531−let

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

533− roundTrip = values_ $

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

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

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

537−:}

538−

539−>>> :set -XOverloadedLists

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

541−>>> :{

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

543− result <- runQueryParams roundTrip input

544− Just output <- firstRow result

545− liftBase . print $ input == output

546−:}

547−True

548−```

549−

550−**Containers**

551−

552−Squeal aims to provide a correspondence between Haskell types and Postgres types.

553−In particular, Haskell ADTs with nullary constructors can correspond to

554−Postgres enum types and Haskell record types can correspond to Postgres

555−composite types. However, it's not always obvious that that's how a user

556−will choose to store values of those types. So Squeal 0.4 introduces newtypes

557−whose purpose is to specify how a user wants to store values of a type.

558−

559−```Haskell

560−newtype Json hask = Json {getJson :: hask}

561−newtype Jsonb hask = Jsonb {getJsonb :: hask}

562−newtype Composite record = Composite {getComposite :: record}

563−newtype Enumerated enum = Enumerated {getEnumerated :: enum}

564−```

565−

566−Let's see an example:

567−

568−```Haskell

569−>>> data Schwarma = Beef | Lamb | Chicken deriving (Eq, Show, GHC.Generic)

570−>>> instance SOP.Generic Schwarma

571−>>> instance SOP.HasDatatypeInfo Schwarma

572−>>>

573−>>> data Person = Person {name :: Text, age :: Int32} deriving (Eq, Show, GHC.Generic)

574−>>> instance SOP.Generic Person

575−>>> instance SOP.HasDatatypeInfo Person

576−>>> instance Aeson.FromJSON Person

577−>>> instance Aeson.ToJSON Person

578−```

579−

580−We can create the equivalent Postgres types directly from their Haskell types.

581−

582−```Haskell

583−>>> :{

584−type Schema =

585− '[ "schwarma" ::: 'Typedef (PG (Enumerated Schwarma))

586− , "person" ::: 'Typedef (PG (Composite Person))

587− ]

588−:}

589−

590−>>> :{

591−let

592− setup :: Definition '[] Schema

593− setup =

594− createTypeEnumFrom @Schwarma #schwarma >>>

595− createTypeCompositeFrom @Person #person

596−:}

597−```

598−

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

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

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

602−

603−```Haskell

604−>>> :{

605−data Row = Row

606− { schwarma :: Enumerated Schwarma

607− , person1 :: Composite Person

608− , person2 :: Json Person

609− } deriving (Eq, GHC.Generic)

610−:}

611−

612−>>> instance Generic Row

613−>>> instance HasDatatypeInfo Row

614−>>> :{

615−let

616− input = Row

617− (Enumerated Chicken)

618− (Composite (Person "Faisal" 24))

619− (Json (Person "Ahmad" 48))

620−:}

621−```

622−

623−Once again, define a round trip query.

624−

625−```Haskell

626−>>> :{

627−let

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

629− roundTrip = values_ $

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

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

632− parameter @3 json `as` #person2

633−:}

634−```

635−

636−Finally, we can drop our type definitions.

637−

638−```Haskell

639−>>> :{

640−let

641− teardown :: Definition Schema '[]

642− teardown = dropType #schwarma >>> dropType #person

643−:}

644−```

645−

646−Now let's run it.

647−

648−```Haskell

649−>>> :{

650−let

651− session = do

652− result <- runQueryParams roundTrip input

653− Just output <- firstRow result

654− liftBase . print $ input == output

655−in

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

657− define setup

658− & pqThen session

659− & pqThen (define teardown)

660−:}

661−True

662−```

663−

664−**With**

665−

666−Squeal 0.3 supported WITH statements but there's a couple problems with them.

667−Here's the type signature for `with` in Squeal 0.3.

668−

669−```Haskell

670−with

671− :: SOP.SListI commons

672− => NP (Aliased (Manipulation schema params)) (common ': commons)

673− -- ^ common table expressions

674− -> Manipulation (With (common ': commons) schema) params results

675− -> Manipulation schema params results

676−```

677−

678−The first problem is that `with` only works with `Manipulations`.

679−It can work on `Query`s by using `queryStatement` but it still will

680−return a `Manipulation`. We can fix this issue by making `with` a

681−method of a type class with instances for both `Query` and `Manipulation`.

682−

683−The second problem is that all the common table expressions

684−refer the base schema, whereas in SQL, each subsequent CTE can

685−refer to previous CTEs as well. But this can be fixed! First define a datatype:

686−

687−```Haskell

688−data CommonTableExpression statement params schema0 schema1 where

689− CommonTableExpression

690− :: Aliased (statement schema params) (alias ::: cte)

691− -> CommonTableExpression statement params schema (alias ::: 'View cte ': schema)

692−```

693−

694−It's just a wrapper around an aliased statement, where the statement

695−could be either a `Query` or `Manipulation`, but it augments the schema

696−by adding a view to it. It almost looks like a morphism between schemas

697−but there is no way yet to compose them. Luckily, Squeal already has

698−a datatype for this, which is used for migrations, the `AlignedList`

699−type which is really the "free category". So we can then define a `With` type class:

700−

701−```Haskell

702−class With statement where

703− with

704− :: AlignedList (CommonTableExpression statement params) schema0 schema1

705− -> statement schema1 params row

706− -> statement schema0 params row

707−```

708−

709−By giving `Aliasable` instances to CTEs and aligned singleton lists of CTEs (i.e. scrap-your-nils), we get a nice syntax for WITH statements in Squeal.

710−

711−Here's an example of using `with` for a `Query` and a `Manipulation`:

712−

713−```Haskell

714−>>> :{

715−let

716− query :: Query

717− '[ "t1" ::: 'View

718− '[ "c1" ::: 'NotNull 'PGtext

719− , "c2" ::: 'NotNull 'PGtext] ]

720− '[]

721− '[ "c1" ::: 'NotNull 'PGtext

722− , "c2" ::: 'NotNull 'PGtext ]

723− query = with (

724− selectStar (from (view #t1)) `as` #t2 :>>

725− selectStar (from (view #t2)) `as` #t3

726− ) (selectStar (from (view #t3)))

727−in printSQL query

728−:}

729−WITH "t2" AS (SELECT * FROM "t1" AS "t1"), "t3" AS (SELECT * FROM "t2" AS "t2") SELECT * FROM "t3" AS "t3"

730−

731−>>> type ProductsTable = '[] :=> '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

732−

733−>>> :{

734−let

735− manipulation :: Manipulation

736− '[ "products" ::: 'Table ProductsTable

737− , "products_deleted" ::: 'Table ProductsTable

738− ] '[ 'NotNull 'PGdate] '[]

739− manipulation = with

740− (deleteFrom #products (#date .< param @1) ReturningStar `as` #deleted_rows)

741− (insertQuery_ #products_deleted (selectStar (from (view (#deleted_rows `as` #t)))))

742−in printSQL manipulation

743−:}

744−WITH "deleted_rows" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "deleted_rows" AS "t"

745−```

746−

747−**Three Valued Logic**

748−

749−In previous versions of Squeal, conditions followed classical two valued logic

750−of `true` and `false`.

751−

752−```Haskell

753−-- Squeal 0.3

754−type Condition schema from grouping params =

755− Expression schema from grouping params ('NotNull 'PGbool)

756−```

757−

758−I had thought that three valued logic, which is what SQL uses, was confusing.

759−However, multiple users reported being confused at being forced to do `NULL`

760−handling, particularly in their left joins. Since the original motivation

761−of being less confusing evaporated I decided to switch to three valued logic

762−of `true`, `false` and `null_`.

763−

764−```Haskell

765−-- Squeal 0.4

766−type Condition schema from grouping params =

767− Expression schema from grouping params ('Null 'PGbool)

768−```

769−

770−**Subquery Expressions**

771−

772−Squeal 0.4 adds support for subquery expressions such as `IN` and `op ANY/ALL`.

773−

774−**Row Types**

775−

776−Squeal 0.4 adds functions to define type expressions from tables and views

777−and a type expression for user defined types, `typetable`, `typeview` and

778−`typedef`.

779−

780−**Runtime Exceptions**

781−

782−Squeal now has an exception type which gives details on the sort of error

783−encountered and handler functions.

784−

785−```Haskell

786−data SquealException

787− = PQException

788− { sqlExecStatus :: LibPQ.ExecStatus

789− , sqlStateCode :: Maybe ByteString

790− -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html

791− , sqlErrorMessage :: Maybe ByteString

792− }

793− | ResultException Text

794− | ParseException Text

795− deriving (Eq, Show)

796−instance Exception SquealException

797−

798−catchSqueal

799− :: MonadBaseControl IO io

800− => io a

801− -> (SquealException -> io a) -- ^ handler

802− -> io a

803−

804−handleSqueal

805− :: MonadBaseControl IO io

806− => (SquealException -> io a) -- ^ handler

807− -> io a -> io a

808−```

809−

810−**Additional Changes**

811−

812−Squeal 0.4 adds `field` and `index` functions to get components of composite

813−and array expressions.

814−

815−Squeal 0.4 adds a dependency on `records-sop` to offload a lot of boilerplate

816−type family logic that was needed for `RowPG`.

817−

818−The above changes required major and minor changes to Squeal DSL functions.

819−Please consult the documentation.

820−

821−### Version 0.3.2 - August 4, 2018

822−

823−Version 0.3.2 features extensive support for `JSON` functionality with

824−more than 50 new functions.

825−This work is entirely due to [Mike Ledger](https://github.com/mikeplus64)

826−who has been making terrific contributions to Squeal. Thanks!

827−We also got some examples in the documentation for pools submitted by

828−[Raveline](https://github.com/Raveline). I'm so pleased to be

829−getting pull requests and issue submissions from you all!

830−

831−### Version 0.3.1 - July 7, 2018

832−

833−Version 0.3.1 of Squeal enables the "Scrap your Nils" trick for

834−heterogeneous lists of `Alias`es, `Aliased` expressions, `PGlabel`s and `By`s

835−with the typeclasses `IsLabel`, `IsQualified`, `IsPGlabel`,

836−and the new `Aliasable` typeclass, to eliminate all need of using `Nil` in a list.

837−There were a couple minor name changes, i.e. the function `group` was renamed to `groupBy`.

838−Please consult the documentation.

839−

840−### Version 0.3 - June 26, 2018

841−

842−Version 0.3 of Squeal adds views as well as composite and enumerated types to Squeal.

843−To support these features, a new kind `SchemumType` was added.

844−

845−```Haskell

846−data SchemumType

847− = Table TableType

848− | View RelationType

849− | Typedef PGType

850−```

851−

852−As a consequence, you will have to update your schema definitions like so:

853−

854−```Haskell

855−-- Squeal 0.2

856−type Schema =

857− '[ "users" :::

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

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

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

861− ]

862− ]

863−

864−-- Squeal 0.3

865−type Schema =

866− '[ "users" ::: 'Table (

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

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

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

870− ])

871− ]

872−```

873−

874−**Views**

875−

876−You can now create, drop, and query views.

877−

878−```Haskell

879−>>> :{

880−type ABC =

881− ('[] :: TableConstraints) :=>

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

883− , "b" ::: 'NoDef :=> 'Null 'PGint4

884− , "c" ::: 'NoDef :=> 'Null 'PGint4

885− ]

886−type BC =

887− '[ "b" ::: 'Null 'PGint4

888− , "c" ::: 'Null 'PGint4

889− ]

890−:}

891−

892−>>> :{

893−let

894− definition :: Definition '["abc" ::: 'Table ABC ] '["abc" ::: 'Table ABC, "bc" ::: 'View BC]

895− definition = createView #bc (select (#b :* #c :* Nil) (from (table #abc)))

896−in printSQL definition

897−:}

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

899−

900−>>> :{

901−let

902− definition :: Definition '["abc" ::: 'Table ABC, "bc" ::: 'View BC] '["abc" ::: 'Table ABC]

903− definition = dropView #bc

904−in printSQL definition

905−:}

906−DROP VIEW "bc";

907−

908−>>> :{

909−let

910− query :: Query '["abc" ::: 'Table ABC, "bc" ::: 'View BC] '[] BC

911− query = selectStar (from (view #bc))

912−in printSQL query

913−:}

914−SELECT * FROM "bc" AS "bc"

915−```

916−

917−**Enumerated Types**

918−

919−PostgreSQL has a powerful type system. It even allows for user defined types.

920−For instance, you can define enumerated types which are data types that comprise

921−a static, ordered set of values. They are equivalent to Haskell algebraic data

922−types whose constructors are nullary. An example of an enum type might be the days of the week,

923−or a set of status values for a piece of data.

924−

925−Enumerated types are created using the `createTypeEnum` command, for example:

926−

927−```Haskell

928−>>> :{

929−let

930− definition :: Definition '[] '["mood" ::: 'Typedef ('PGenum '["sad", "ok", "happy"])]

931− definition = createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy" :* Nil)

932−:}

933−>>> printSQL definition

934−CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');

935−```

936−

937−Enumerated types can also be generated from a Haskell algebraic data type with nullary constructors, for example:

938−

939−```Haskell

940−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

941−>>> instance SOP.Generic Schwarma

942−>>> instance SOP.HasDatatypeInfo Schwarma

943−

944−>>> :kind! EnumFrom Schwarma

945−EnumFrom Schwarma :: PGType

946−= 'PGenum '["Beef", "Lamb", "Chicken"]

947−

948−>>> :{

949−let

950− definition :: Definition '[] '["schwarma" ::: 'Typedef (EnumFrom Schwarma)]

951− definition = createTypeEnumFrom @Schwarma #schwarma

952−:}

953−>>> printSQL definition

954−CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');

955−```

956−

957−You can express values of an enum type using `label`, which is an overloaded method

958−of the `IsPGlabel` typeclass.

959−

960−```Haskell

961−>>> :{

962−let

963− expression :: Expression sch rels grp params ('NotNull (EnumFrom Schwarma))

964− expression = label @"Chicken"

965−in printSQL expression

966−:}

967−'Chicken'

968−```

969−

970−**Composite Types**

971−

972−In addition to enum types, you can define composite types.

973−A composite type represents the structure of a row or record;

974−it is essentially just a list of field names and their data types.

975−

976−

977−`createTypeComposite` creates a composite type. The composite type is

978−specified by a list of attribute names and data types.

979−

980−```Haskell

981−>>> :{

982−let

983− definition :: Definition '[] '["complex" ::: 'Typedef ('PGcomposite '["real" ::: 'PGfloat8, "imaginary" ::: 'PGfloat8])]

984− definition = createTypeComposite #complex (float8 `As` #real :* float8 `As` #imaginary :* Nil)

985−:}

986−>>> printSQL definition

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

988−```

989−

990−Composite types are almost equivalent to Haskell record types.

991−However, because of the potential presence of `NULL`

992−all the record fields must be `Maybe`s of basic types.

993−Composite types can be generated from a Haskell record type, for example:

994−

995−```Haskell

996−>>> data Complex = Complex {real :: Maybe Double, imaginary :: Maybe Double} deriving GHC.Generic

997−>>> instance SOP.Generic Complex

998−>>> instance SOP.HasDatatypeInfo Complex

999−

1000−>>> :kind! CompositeFrom Complex

1001−CompositeFrom Complex :: PGType

1002−= 'PGcomposite '['("real", 'PGfloat8), '("imaginary", 'PGfloat8)]

1003−

1004−>>> :{

1005−let

1006− definition :: Definition '[] '["complex" ::: 'Typedef (CompositeFrom Complex)]

1007− definition = createTypeCompositeFrom @Complex #complex

1008−in printSQL definition

1009−:}

1010−CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);

1011−```

1012−

1013−A row constructor is an expression that builds a row value

1014−(also called a composite value) using values for its member fields.

1015−

1016−```Haskell

1017−>>> :{

1018−let

1019− i :: Expression '[] '[] 'Ungrouped '[] ('NotNull (CompositeFrom Complex))

1020− i = row (0 `As` #real :* 1 `As` #imaginary :* Nil)

1021−:}

1022−>>> printSQL i

1023−ROW(0, 1)

1024−```

1025−

1026−You can also use `(&)` to apply a field label to a composite value.

1027−

1028−```Haskell

1029−>>> :{

1030−let

1031− expr :: Expression '[] '[] 'Ungrouped '[] ('Null 'PGfloat8)

1032− expr = i & #imaginary

1033−in printSQL expr

1034−:}

1035−(ROW(0, 1)).imaginary

1036−```

1037−

1038−Both composite and enum types can be automatically encoded from and decoded to their equivalent Haskell types.

1039−And they can be dropped.

1040−

1041−```Haskell

1042−>>> :{

1043−let

1044− definition :: Definition '["mood" ::: 'Typedef ('PGenum '["sad", "ok", "happy"])] '[]

1045− definition = dropType #mood

1046−:}

1047−>>> printSQL definition

1048−DROP TYPE "mood";

1049−```

1050−

1051−**Additional Changes**

1052−

1053−Squeal 0.3 also introduces a typeclass `HasAll` similar to `Has` but for a list of aliases.

1054−This makes it possible to clean up some unfortunately messy Squeal 0.2 definitions.

1055−

1056−```Haskell

1057−-- Squeal 0.2

1058−>>> unique (Column #a :* Column #b :* Nil)

1059−

1060−-- Squeal 0.3

1061−>>> unique (#a :* #b :* Nil)

1062−```

1063−

1064−Squeal 0.3 also adds `IsLabel` instances for `Aliased` expressions and tables as well as

1065−heterogeneous lists, allowing for some more economy of code.

1066−

1067−```Haskell

1068−-- Squeal 0.2 (or 0.3)

1069−>>> select (#a `As` #a :* Nil) (from (table (#t `As` #t)))

1070−

1071−-- Squeal 0.3

1072−>>> select #a (from (table #t))

1073−```

1074−

1075−Squeal 0.3 also fixes a bug that prevented joined queries on self-referencing tables.

1076−

1077−The above changes required major and minor changes to Squeal DSL functions.

1078−Please consult the documentation.

1079−

1080### Version 0.2.1 - April 7, 2018

3### Version 0.2.1 - April 7, 2018

1081

1082This minor update fixes an issue where alias identifiers could conflict with

5This minor update fixes an issue where alias identifiers could conflict with

scrap-your-nils.mddeleted−60

@@ -1,60 +0,0 @@

1−## Scrap your Nils

2−

3−One of the most useful types I've come across in Haskell is the type of

4−"heterogeneous lists". This is the same as the [Rec](http://hackage.haskell.org/package/vinyl-0.8.1.1/docs/Data-Vinyl-Core.html)

5−datatype from the [vinyl](http://hackage.haskell.org/package/vinyl) library.

6−It's also the same as the [NP](http://hackage.haskell.org/package/generics-sop-0.3.2.0/docs/Generics-SOP-NP.html)

7−datatype from the [generics-sop](http://hackage.haskell.org/package/generics-sop) library.

8−Squeal makes heavy use of this type.

9−

10−```Haskell

11−>>> import Generics.SOP (NP(..))

12−>>> :i NP

13−type role NP representational nominal

14−data NP (a :: k -> *) (b :: [k]) where

15− Nil :: forall k (a :: k -> *). NP a '[]

16− (:*) :: forall k (a :: k -> *) (x :: k) (xs :: [k]).

17− (a x) -> (NP a xs) -> NP a (x : xs)

18− -- Defined in ‘Generics.SOP.NP’

19−```

20−

21−This type allows us to construct "product" types, where the types of the individual

22−"terms" are hosted at the type level.

23−

24−```Haskell

25−>>> :set -XDataKinds

26−>>> import Generics.SOP (I(..))

27−>>> let example = I "foo" :* I pi :* Nil :: NP I '[String, Double]

28−>>> example

29−I "foo" :* I 3.141592653589793 :* Nil

30−```

31−

32−One thing Squeal uses `NP` for is to form lists of aliases,

33−using GHC's `OverloadedLabels` extension, hosting the names

34−of the aliases themselves at the type level.

35−

36−```Haskell

37−>>> :set -XKindSignatures -XOverloadedLabels -XFlexibleInstances -XMultiParamTypeClasses

38−>>> import GHC.TypeLits

39−>>> import GHC.OverloadedLabels

40−>>> data Alias (alias :: Symbol) = Alias deriving (Eq,Ord,Show)

41−>>> instance IsLabel label (Alias label) where fromLabel = Alias

42−>>> let aliases = #foo :* #bar :* Nil :: NP Alias '["foo", "bar"]

43−```

44−

45−However, it's very ugly to have to end every list with `:* Nil`.

46−When I announced the release of Squeal, people rightly [complained](https://www.reddit.com/r/haskell/comments/6yr5v6/announcing_squeal_a_deep_embedding_of_sql_in/dmq8vvn)

47−about the syntactic noise. Luckily, there's a neat trick we can use to get rid of it.

48−Making an `IsLabel` instance not only for elements of our list

49−but also for lists of length 1, we can ask GHC to interpret

50−the last label as a list.

51−

52−```Haskell

53−>>> instance IsLabel label (NP Alias '[label]) where fromLabel = Alias :* Nil

54−>>> let aliases' = #foo :* #bar :: NP Alias '["foo", "bar"]

55−```

56−

57−Version 0.3.1 of Squeal enables the "Scrap your Nils" trick for

58−heterogeneous lists of `Alias`es, `Aliased` expressions, `PGlabel`s and `By`s

59−with the typeclasses `IsLabel`, `IsQualified`, `IsPGlabel`,

60−and the new `Aliasable` typeclass, to eliminate all need of using `Nil` in a list.

squeal-postgresql/exe/Example.hs+49−46

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

12module Main (main, main2) where

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

14+import Control.Monad (void)

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

15import Data.Int (Int16, Int32)

16import Data.Int (Int16, Int32)

16import Data.Monoid ((<>))

17import Data.Monoid ((<>))

17import Data.Text (Text)

18import Data.Text (Text)

@@ -28,7 +29,7 @@ type Schema =

28 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

29 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

29 '[ "id" ::: 'Def :=> 'NotNull 'PGint4

30 '[ "id" ::: 'Def :=> 'NotNull 'PGint4

30 , "name" ::: 'NoDef :=> 'NotNull 'PGtext

31 , "name" ::: 'NoDef :=> 'NotNull 'PGtext

31− , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray ('Null 'PGint2))

32+ , "vec" ::: 'NoDef :=> 'NotNull ('PGvararray 'PGint2)

32 ])

33 ])

33 , "emails" ::: 'Table (

34 , "emails" ::: 'Table (

34 '[ "pk_emails" ::: 'PrimaryKey '["id"]

35 '[ "pk_emails" ::: 'PrimaryKey '["id"]

@@ -38,70 +39,72 @@ type Schema =

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

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

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

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

40 ])

41 ])

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

42 ]

44−type Schemas = Public Schema

45−

46−setup :: Definition (Public '[]) Schemas

44+setup :: Definition '[] Schema

47−setup =

45+setup =

48 createTable #users

46 createTable #users

49− ( serial `as` #id :*

47+ ( serial `As` #id :*

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

48+ (text & notNull) `As` #name :*

51− (vararray int2 & notNullable) `as` #vec )

49+ (vararray int2 & notNull) `As` #vec :* Nil )

52− ( primaryKey #id `as` #pk_users )

50+ ( primaryKey #id `As` #pk_users :* Nil )

53 >>>

51 >>>

54 createTable #emails

52 createTable #emails

55− ( serial `as` #id :*

53+ ( serial `As` #id :*

56− hask @Int32 `as` #user_id :*

54+ (int & notNull) `As` #user_id :*

57− hask @(Maybe Text) `as` #email )

55+ (text & null_) `As` #email :* Nil )

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

56+ ( primaryKey #id `As` #pk_emails :*

59 foreignKey #user_id #users #id

57 foreignKey #user_id #users #id

60− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

58+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )

61− >>>

59+

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

63−

64−teardown :: Definition Schemas (Public '[])

60+teardown :: Definition Schema '[]

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

61+teardown = dropTable #emails >>> dropTable #users

66−

62+

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

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

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

68−insertUser = insertInto #users

65+insertUser = insertRows #users

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

66+ (Default `As` #id :* Set (param @1) `As` #name :* Set (param @2) `As` #vec :* Nil) []

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

67+ OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))

71−

68+

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

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

73−insertEmail = insertInto_ #emails

70+insertEmail = insertRows #emails

71+ ( Default `As` #id :*

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

72+ Set (param @1) `As` #user_id :*

75−

73+ Set (param @2) `As` #email :* Nil ) []

76−getUsers :: Query_ Schemas () User

74+ OnConflictDoNothing (Returning Nil)

75+

76+getUsers :: Query Schema '[]

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

78+ , "userEmail" ::: 'Null 'PGtext

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

77−getUsers = select_

80+getUsers = select

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

81+ (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* #u ! #vec `As` #userVec :* Nil)

79− ( from (table (#users `as` #u)

82+ ( from (table (#users `As` #u)

80− & innerJoin (table (#emails `as` #e))

83+ & innerJoin (table (#emails `As` #e))

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

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

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

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

84 deriving (Show, GHC.Generic)

87 deriving (Show, GHC.Generic)

85instance SOP.Generic User

88instance SOP.Generic User

86instance SOP.HasDatatypeInfo User

89instance SOP.HasDatatypeInfo User

88users :: [User]

91users :: [User]

89−users =

92+users =

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

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

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

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

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

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

93 ]

96 ]

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

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

96session = do

99session = do

97− liftIO $ Char8.putStrLn "manipulating"

100+ liftBase $ Char8.putStrLn "manipulating"

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

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

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

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

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

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

101− liftIO $ Char8.putStrLn "querying"

104+ liftBase $ Char8.putStrLn "querying"

102 usersResult <- runQuery getUsers

105 usersResult <- runQuery getUsers

103 usersRows <- getRows usersResult

106 usersRows <- getRows usersResult

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

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

105

108

106main :: IO ()

109main :: IO ()

107main = do

110main = do

@@ -119,7 +122,7 @@ main = do

119

122

120main2 :: IO ()

123main2 :: IO ()

121main2 =

124main2 =

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

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

123 define setup

126 define setup

124 & pqThen session

127 & pqThen session

125 & pqThen (define teardown)

128 & pqThen (define teardown)

squeal-postgresql/squeal-postgresql.cabal+13−74

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

1name: squeal-postgresql

2−version: 0.5.1.0

2+version: 0.2.1.0

3synopsis: Squeal PostgreSQL Library

4description: Squeal is a type-safe embedding of PostgreSQL in Haskell

5homepage: https://github.com/morphismtech/squeal

@@ -22,116 +22,54 @@ library

22 hs-source-dirs: src

23 exposed-modules:

24 Squeal.PostgreSQL

25− Squeal.PostgreSQL.Alias

26 Squeal.PostgreSQL.Binary

25 Squeal.PostgreSQL.Binary

27 Squeal.PostgreSQL.Definition

26 Squeal.PostgreSQL.Definition

28− Squeal.PostgreSQL.Definition.Function

29− Squeal.PostgreSQL.Definition.Index

30− Squeal.PostgreSQL.Definition.Table

31− Squeal.PostgreSQL.Definition.Table.Constraint

32− Squeal.PostgreSQL.Definition.Type

33− Squeal.PostgreSQL.Definition.Schema

34− Squeal.PostgreSQL.Definition.View

35 Squeal.PostgreSQL.Expression

27 Squeal.PostgreSQL.Expression

36− Squeal.PostgreSQL.Expression.Aggregate

37− Squeal.PostgreSQL.Expression.Collection

38− Squeal.PostgreSQL.Expression.Comparison

39− Squeal.PostgreSQL.Expression.Json

40− Squeal.PostgreSQL.Expression.Literal

41− Squeal.PostgreSQL.Expression.Logic

42− Squeal.PostgreSQL.Expression.Math

43− Squeal.PostgreSQL.Expression.Null

44− Squeal.PostgreSQL.Expression.Parameter

45− Squeal.PostgreSQL.Expression.Range

46− Squeal.PostgreSQL.Expression.Set

47− Squeal.PostgreSQL.Expression.Sort

48− Squeal.PostgreSQL.Expression.Subquery

49− Squeal.PostgreSQL.Expression.Text

50− Squeal.PostgreSQL.Expression.TextSearch

51− Squeal.PostgreSQL.Expression.Time

52− Squeal.PostgreSQL.Expression.Type

53− Squeal.PostgreSQL.Expression.Window

54− Squeal.PostgreSQL.List

55 Squeal.PostgreSQL.Manipulation

28 Squeal.PostgreSQL.Manipulation

56 Squeal.PostgreSQL.Migration

29 Squeal.PostgreSQL.Migration

57 Squeal.PostgreSQL.Pool

30 Squeal.PostgreSQL.Pool

58− Squeal.PostgreSQL.PG

59 Squeal.PostgreSQL.PQ

31 Squeal.PostgreSQL.PQ

60 Squeal.PostgreSQL.Render

32 Squeal.PostgreSQL.Render

61 Squeal.PostgreSQL.Query

33 Squeal.PostgreSQL.Query

62 Squeal.PostgreSQL.Schema

34 Squeal.PostgreSQL.Schema

63 Squeal.PostgreSQL.Transaction

35 Squeal.PostgreSQL.Transaction

64 default-language: Haskell2010

36 default-language: Haskell2010

65− ghc-options: -Wall

37+ ghc-options: -Wall -fprint-explicit-kinds

66 build-depends:

38 build-depends:

67 aeson >= 1.2.4.0

39 aeson >= 1.2.4.0

68− , base >= 4.11.1.0 && < 5.0

40+ , base >= 4.10.1.0 && < 5.0

69− , binary-parser >= 0.5.5

41+ , binary-parser

42+ , bytestring-strict-builder

70 , bytestring >= 0.10.8.2

43 , bytestring >= 0.10.8.2

71− , bytestring-strict-builder >= 0.4.5

72 , deepseq >= 1.4.3.0

44 , deepseq >= 1.4.3.0

73− , free-categories >= 0.1.0.0

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

45+ , generics-sop >= 0.3.2.0

46+ , lifted-base >= 0.2.3.12

75 , mmorph >= 1.1.1

47 , mmorph >= 1.1.1

48+ , monad-control >= 1.0.2.3

76 , mtl >= 2.2.2

49 , mtl >= 2.2.2

77 , network-ip >= 0.3.0.2

50 , network-ip >= 0.3.0.2

78 , postgresql-binary >= 0.12.1

51 , postgresql-binary >= 0.12.1

79 , postgresql-libpq >= 0.9.4.1

52 , postgresql-libpq >= 0.9.4.1

80− , records-sop >= 0.1.0.0

81 , resource-pool >= 0.2.3.2

53 , resource-pool >= 0.2.3.2

82 , scientific >= 0.3.5.3

54 , scientific >= 0.3.5.3

83 , text >= 1.2.3.0

55 , text >= 1.2.3.0

84 , time >= 1.8.0.2

56 , time >= 1.8.0.2

85 , transformers >= 0.5.2.0

57 , transformers >= 0.5.2.0

86− , unliftio >= 0.2.10

58+ , transformers-base >= 0.4.4

87− , unliftio-pool >= 0.2.1.0

88 , uuid-types >= 1.0.3

59 , uuid-types >= 1.0.3

89 , vector >= 0.12.0.1

60 , vector >= 0.12.0.1

91−test-suite doctest

62+test-suite squeal-postgresql-doctest

92 default-language: Haskell2010

63 default-language: Haskell2010

93 type: exitcode-stdio-1.0

64 type: exitcode-stdio-1.0

94 hs-source-dirs: test

65 hs-source-dirs: test

95 ghc-options: -Wall

66 ghc-options: -Wall

96− main-is: Doc.hs

67+ main-is: DocTest.hs

97 build-depends:

68 build-depends:

98 base >= 4.10.0.0

69 base >= 4.10.0.0

99 , doctest >= 0.11.4

70 , doctest >= 0.11.4

100− , squeal-postgresql

101−

102−test-suite properties

103− default-language: Haskell2010

104− type: exitcode-stdio-1.0

105− hs-source-dirs: test

106− ghc-options: -Wall

107− main-is: Property.hs

108− build-depends:

109− base >= 4.10.0.0

110− , bytestring >= 0.10.8.2

111− , hedgehog >= 1.0

112− , mtl >= 2.2.2

113− , scientific >= 0.3.5.3

114− , squeal-postgresql

115− , time >= 1.8.0.2

116−

117−test-suite spec

118− default-language: Haskell2010

119− type: exitcode-stdio-1.0

120− hs-source-dirs: test

121− ghc-options: -Wall

122− main-is: Spec.hs

123− build-depends:

124− base >= 4.10.0.0

125− , async >= 2.2.2

126− , bytestring >= 0.10.8.2

127− , generics-sop >= 0.3.1.0

128− , hspec >= 2.4.8

129− , mtl >= 2.2.2

130− , squeal-postgresql

131− , text >= 1.2.2.2

132− , vector >= 0.12.0.1

133

134−executable example

72+executable squeal-postgresql-example

135 default-language: Haskell2010

73 default-language: Haskell2010

136 hs-source-dirs: exe

74 hs-source-dirs: exe

137 ghc-options: -Wall

75 ghc-options: -Wall

@@ -144,4 +82,5 @@ executable example

144 , squeal-postgresql

82 , squeal-postgresql

145 , text >= 1.2.2.2

83 , text >= 1.2.2.2

146 , transformers >= 0.5.2.0

84 , transformers >= 0.5.2.0

85+ , transformers-base >= 0.4.4

147 , vector >= 0.12.0.1

86 , vector >= 0.12.0.1

squeal-postgresql/src/Squeal/PostgreSQL.hs+222−233

@@ -1,233 +1,222 @@

1−{-|

2−Module: Squeal.PostgreSQL

1+-- | Module: Squeal.PostgreSQL

3−Description: Squeal export module

2+-- Description: Squeel export module

4−Copyright: (c) Eitan Chatav, 2019

3+-- Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

4+-- Maintainer: eitan@morphism.tech

6−Stability: experimental

5+-- Stability: experimental

7−

6+--

8−Squeal is a deep embedding of [PostgreSQL](https://www.postgresql.org) in Haskell.

7+-- Squeal is a deep embedding of [PostgreSQL](https://www.postgresql.org) in Haskell.

9−Let's see an example!

8+-- Let's see an example!

10−

9+--

11−First, we need some language extensions because Squeal uses modern GHC

10+-- First, we need some language extensions because Squeal uses modern GHC

12−features.

11+-- features.

13−

12+--

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

13+-- >>> :set -XDataKinds -XDeriveGeneric -XOverloadedLabels

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

14+-- >>> :set -XOverloadedStrings -XTypeApplications -XTypeOperators

16−

15+--

17−We'll need some imports.

16+-- We'll need some imports.

18−

17+--

19−>>> import Control.Monad.IO.Class (liftIO)

18+-- >>> import Control.Monad (void)

19+-- >>> import Control.Monad.Base (liftBase)

20−>>> import Data.Int (Int32)

20+-- >>> import Data.Int (Int32)

21−>>> import Data.Text (Text)

21+-- >>> import Data.Text (Text)

22−>>> import Squeal.PostgreSQL

22+-- >>> import Squeal.PostgreSQL

23−

23+--

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

24+-- We'll use generics to easily convert between Haskell and PostgreSQL values.

25−

25+--

26−>>> import qualified Generics.SOP as SOP

26+-- >>> import qualified Generics.SOP as SOP

27−>>> import qualified GHC.Generics as GHC

27+-- >>> import qualified GHC.Generics as GHC

28−

28+--

29−The first step is to define the schema of our database. This is where

29+-- The first step is to define the schema of our database. This is where

30−we use @DataKinds@ and @TypeOperators@.

30+-- we use @DataKinds@ and @TypeOperators@.

31−

31+--

32−>>> :{

32+-- >>> :{

33−type UsersColumns =

33+-- type Schema =

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

34+-- '[ "users" ::: 'Table (

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

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

35+-- '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

37−type EmailsColumns =

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

36+-- '[ "id" ::: 'Def :=> 'NotNull 'PGint4

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

37+-- , "name" ::: 'NoDef :=> 'NotNull 'PGtext

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

38+-- ])

41−type EmailsConstraints =

39+-- , "emails" ::: 'Table (

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

40+-- '[ "pk_emails" ::: 'PrimaryKey '["id"]

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

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

44−type Schema =

42+-- ] :=>

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

43+-- '[ "id" ::: 'Def :=> 'NotNull 'PGint4

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

44+-- , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

47−type Schemas = Public Schema

45+-- , "email" ::: 'NoDef :=> 'Null 'PGtext

46+-- ])

47+-- ]

48−:}

48+-- :}

49−

49+--

50−Notice the use of type operators.

50+-- Notice the use of type operators. `:::` is used

51−

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

51+-- to pair an alias `Symbol` with either a `TableType` or a `ColumnType`.

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

54−operator.

55−

56−`:=>` is used to pair `TableConstraints` with a `ColumnsType`,

52+-- `:=>` is used to pair a `TableConstraint`s with a `ColumnsType`,

57−yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

53+-- yielding a `TableType`, or to pair a `ColumnConstraint` with a `NullityType`,

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

54+-- yielding a `ColumnType`.

59−

55+--

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

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

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

57+-- Squeal, a `Definition` is a `createTable`, `alterTable` or `dropTable`

62−has two type parameters, corresponding to the schema

58+-- command and has two type parameters, corresponding to the schema

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

59+-- before being run and the schema after. We can compose definitions using

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

60+-- `>>>`. Here and in the rest of our commands we make use of overloaded

65−labels to refer to named tables and columns in our schema.

61+-- labels to refer to named tables and columns in our schema.

66−

62+--

67−>>> :{

63+-- >>> :{

68−let

64+-- let

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

65+-- setup :: Definition '[] Schema

70− setup =

66+-- setup =

71− createTable #users

67+-- createTable #users

72− ( serial `as` #id :*

68+-- ( serial `As` #id :*

73− (text & notNullable) `as` #name )

69+-- (text & notNull) `As` #name :* Nil )

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

70+-- ( primaryKey #id `As` #pk_users :* Nil ) >>>

75− createTable #emails

71+-- createTable #emails

76− ( serial `as` #id :*

72+-- ( serial `As` #id :*

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

73+-- (int & notNull) `As` #user_id :*

78− (text & nullable) `as` #email )

74+-- (text & null_) `As` #email :* Nil )

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

75+-- ( primaryKey #id `As` #pk_emails :*

80− foreignKey #user_id #users #id

76+-- foreignKey #user_id #users #id

81− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

77+-- OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )

82−:}

78+-- :}

83−

79+--

84−We can easily see the generated SQL is unsurprising looking.

80+-- We can easily see the generated SQL is unsuprising looking.

85−

81+--

86−>>> printSQL setup

82+-- >>> renderDefinition setup

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

88−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);

83+-- "CREATE TABLE \"users\" (\"id\" serial, \"name\" text NOT NULL, CONSTRAINT \"pk_users\" PRIMARY KEY (\"id\")); 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);"

89−

84+--

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

85+-- Notice that @setup@ starts with an empty schema @'[]@ and produces @Schema@.

91−In our `createTable` commands we included `TableConstraint`s to define

86+-- In our `createTable` commands we included `TableConstraint`s to define

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

87+-- primary and foreign keys, making them somewhat complex. Our tear down

93−`Definition` is simpler.

88+-- `Definition` is simpler.

94−

89+--

95−>>> :{

90+-- >>> :{

96−let

91+-- let

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

92+-- teardown :: Definition Schema '[]

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

93+-- teardown = dropTable #emails >>> dropTable #users

99−:}

94+-- :}

100−

95+--

101−>>> printSQL teardown

96+-- >>> renderDefinition teardown

102−DROP TABLE "emails";

97+-- "DROP TABLE \"emails\"; DROP TABLE \"users\";"

103−DROP TABLE "users";

98+--

104−

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.

99+-- Next, we'll write `Manipulation`s to insert data into our two tables.

113−A `Manipulation_` like `insertInto`, `update` or `deleteFrom`

100+-- A `Manipulation` is an `insertRow` (or other inserts), `update`

101+-- or `deleteFrom` command and

114−has three type parameters, the schemas it refers to, input parameters

102+-- has three type parameters, the schema it refers to, a list of parameters

115−and an output row. When

103+-- it can take as input, and a list of columns it produces as output. When

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

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

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

105+-- field but not for the @id@ field. Since it's optional, we can use a default

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

106+-- value. However, since the emails table refers to the users table, we will

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

107+-- need to retrieve the user id that the insert generates and insert it into

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

108+-- the emails table. Take a careful look at the type and definition of both

121−`with` statement.

109+-- of our inserts.

122−

110+--

123−>>> :{

111+-- >>> :{

124−let

112+-- let

125− insertUser :: Manipulation_ Schemas User ()

113+-- insertUser :: Manipulation Schema '[ 'NotNull 'PGtext ] '[ "fromOnly" ::: 'NotNull 'PGint4 ]

126− insertUser = with (u `as` #u) e

114+-- insertUser = insertRow #users

127− where

128− u = insertInto #users

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

115+-- (Default `As` #id :* Set (param @1) `As` #name :* Nil)

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

116+-- OnConflictDoNothing (Returning (#id `As` #fromOnly :* Nil))

131− e = insertInto_ #emails $ Select

117+-- :}

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

118+--

133− (from (common #u))

119+-- >>> :{

120+-- let

121+-- insertEmail :: Manipulation Schema '[ 'NotNull 'PGint4, 'Null 'PGtext] '[]

122+-- insertEmail = insertRow #emails

123+-- ( Default `As` #id :*

124+-- Set (param @1) `As` #user_id :*

125+-- Set (param @2) `As` #email :* Nil )

126+-- OnConflictDoNothing (Returning Nil)

134−:}

127+-- :}

135−

128+--

136−>>> printSQL insertUser

129+-- >>> renderManipulation insertUser

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

130+-- "INSERT INTO \"users\" (\"id\", \"name\") VALUES (DEFAULT, ($1 :: text)) ON CONFLICT DO NOTHING RETURNING \"id\" AS \"fromOnly\";"

138−

131+-- >>> renderManipulation insertEmail

132+-- "INSERT INTO \"emails\" (\"id\", \"user_id\", \"email\") VALUES (DEFAULT, ($1 :: int4), ($2 :: text)) ON CONFLICT DO NOTHING;"

133+--

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

134+-- Next we write a `Query` to retrieve users from the database. We're not

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

135+-- interested in the ids here, just the usernames and email addresses. We

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

136+-- need to use an inner join to get the right result. A `Query` is like a

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

137+-- `Manipulation` with the same kind of type parameters.

143−

138+--

144−>>> :{

139+-- >>> :{

145−let

140+-- let

146− getUsers :: Query_ Schemas () User

141+-- getUsers :: Query Schema '[]

142+-- '[ "userName" ::: 'NotNull 'PGtext

143+-- , "userEmail" ::: 'Null 'PGtext ]

147− getUsers = select_

144+-- getUsers = select

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

145+-- (#u ! #name `As` #userName :* #e ! #email `As` #userEmail :* Nil)

149− ( from (table (#users `as` #u)

146+-- ( from (table (#users `As` #u)

150− & innerJoin (table (#emails `as` #e))

147+-- & innerJoin (table (#emails `As` #e))

151− (#u ! #id .== #e ! #user_id)) )

148+-- (#u ! #id .== #e ! #user_id)) )

152−:}

149+-- :}

153−

150+--

154−>>> printSQL getUsers

151+-- >>> renderQuery getUsers

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

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

156−

153+--

154+-- Now that we've defined the SQL side of things, we'll need a Haskell type

155+-- for users. We give the type `Generics.SOP.Generic` and

156+-- `Generics.SOP.HasDatatypeInfo` instances so that we can decode the rows

157+-- we receive when we run @getUsers@. Notice that the record fields of the

158+-- @User@ type match the column names of @getUsers@.

159+--

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

161+-- >>> instance SOP.Generic User

162+-- >>> instance SOP.HasDatatypeInfo User

163+--

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

164+-- Let's also create some users to add to the database.

158−

165+--

159−>>> :{

166+-- >>> :{

160−let

167+-- let

161− users :: [User]

168+-- users :: [User]

162− users =

169+-- users =

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

170+-- [ User "Alice" (Just "alice@gmail.com")

164− , User "Bob" Nothing

171+-- , User "Bob" Nothing

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

172+-- , User "Carole" (Just "carole@hotmail.com")

166− ]

173+-- ]

167−:}

174+-- :}

168−

175+--

169−Now we can put together all the pieces into a program. The program

176+-- Now we can put together all the pieces into a program. The program

170−connects to the database, sets up the schema, inserts the user data

177+-- connects to the database, sets up the schema, inserts the user data

171−(using prepared statements as an optimization), queries the user

178+-- (using prepared statements as an optimization), queries the user

172−data and prints it out and finally closes the connection. We can thread

179+-- data and prints it out and finally closes the connection. We can thread

173−the changing schema information through by using the indexed `PQ` monad

180+-- the changing schema information through by using the indexed `PQ` monad

174−transformer and when the schema doesn't change we can use `Monad` and

181+-- transformer and when the schema doesn't change we can use `Monad` and

175−`MonadPQ` functionality.

182+-- `MonadPQ` functionality.

176−

183+--

177−>>> :{

184+-- >>> :{

178−let

185+-- let

179− session :: PQ Schemas Schemas IO ()

186+-- session :: PQ Schema Schema IO ()

180− session = do

187+-- session = do

188+-- idResults <- traversePrepared insertUser (Only . userName <$> users)

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

181− _ <- traversePrepared_ insertUser users

190+-- traversePrepared_ insertEmail (zip (ids :: [Int32]) (userEmail <$> users))

182− usersResult <- runQuery getUsers

191+-- usersResult <- runQuery getUsers

183− usersRows <- getRows usersResult

192+-- usersRows <- getRows usersResult

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

193+-- liftBase $ print (usersRows :: [User])

185−in

194+-- :}

195+--

196+-- >>> :{

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

197+-- void . withConnection "host=localhost port=5432 dbname=exampledb" $

187− define setup

198+-- define setup

188− & pqThen session

199+-- & pqThen session

189− & pqThen (define teardown)

200+-- & pqThen (define teardown)

190−:}

201+-- :}

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

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

192−-}

203+

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

204+module Squeal.PostgreSQL

194−

195−import Squeal.PostgreSQL.Alias as X

196−import Squeal.PostgreSQL.Binary as X

205+ ( module Squeal.PostgreSQL.Binary

197−import Squeal.PostgreSQL.Definition as X

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

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

206+ , module Squeal.PostgreSQL.Definition

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

207+ , module Squeal.PostgreSQL.Expression

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

208+ , module Squeal.PostgreSQL.Manipulation

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

209+ , module Squeal.PostgreSQL.PQ

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

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

210+ , module Squeal.PostgreSQL.Query

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

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

211+ , module Squeal.PostgreSQL.Schema

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

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

212+ , module Squeal.PostgreSQL.Transaction

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

213+ ) where

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

214+

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

215+import Squeal.PostgreSQL.Binary

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

216+import Squeal.PostgreSQL.Definition

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

217+import Squeal.PostgreSQL.Expression

224−import Squeal.PostgreSQL.List as X

218+import Squeal.PostgreSQL.Manipulation

225−import Squeal.PostgreSQL.Manipulation as X

226−import Squeal.PostgreSQL.Migration as X

227−import Squeal.PostgreSQL.PG as X

219+import Squeal.PostgreSQL.PQ

228−import Squeal.PostgreSQL.Pool as X

229−import Squeal.PostgreSQL.PQ as X

230−import Squeal.PostgreSQL.Query as X

220+import Squeal.PostgreSQL.Query

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

221+import Squeal.PostgreSQL.Schema

232−import Squeal.PostgreSQL.Schema as X

233−import Squeal.PostgreSQL.Transaction as X

222+import Squeal.PostgreSQL.Transaction

squeal-postgresql/src/Squeal/PostgreSQL/Alias.hsdeleted−249

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

1−{-|

2−Module: Squeal.PostgreSQL.Alias

3−Description: Aliases

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−This module embeds Postgres's alias system in Haskell in

9−a typesafe fashion. Thanks to GHC's @OverloadedLabels@ extension,

10−Squeal can reference aliases by prepending with a @#@.

11−-}

12−

13−{-# LANGUAGE

14− AllowAmbiguousTypes

15− , ConstraintKinds

16− , DeriveAnyClass

17− , DeriveGeneric

18− , FlexibleContexts

19− , FlexibleInstances

20− , FunctionalDependencies

21− , GADTs

22− , LambdaCase

23− , OverloadedStrings

24− , QuantifiedConstraints

25− , RankNTypes

26− , ScopedTypeVariables

27− , StandaloneDeriving

28− , TypeApplications

29− , TypeFamilyDependencies

30− , TypeInType

31− , TypeOperators

32− , UndecidableInstances

33− , UndecidableSuperClasses

34−#-}

35−

36−module Squeal.PostgreSQL.Alias

37− ( (:::)

38− , Alias (..)

39− , IsLabel (..)

40− , Aliased (As)

41− , Aliasable (as)

42− , renderAliased

43− , Has

44− , HasUnique

45− , HasAll

46− , HasIn

47− , QualifiedAlias (..)

48− , IsQualified (..)

49− -- * Grouping

50− , Grouping (..)

51− , GroupedBy

52− ) where

53−

54−import Control.DeepSeq

55−import Data.ByteString (ByteString)

56−import Data.String (fromString)

57−import GHC.OverloadedLabels

58−import GHC.TypeLits

59−

60−import qualified Generics.SOP as SOP

61−import qualified GHC.Generics as GHC

62−

63−import Squeal.PostgreSQL.List

64−import Squeal.PostgreSQL.Render

65−

66−-- $setup

67−-- >>> import Squeal.PostgreSQL

68−

69−-- | The alias operator `:::` is like a promoted version of `As`,

70−-- a type level pair between an alias and some type.

71−type (:::) (alias :: Symbol) ty = '(alias,ty)

72−infixr 6 :::

73−

74−

75−-- | `Grouping` is an auxiliary namespace, created by

76−-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used

77−-- for typesafe aggregation

78−data Grouping

79− = Ungrouped -- ^ no aggregation permitted

80− | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped

81−

82−{- | A `GroupedBy` constraint indicates that a table qualified column is

83−a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,

84−may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.

85−-}

86−class (KnownSymbol table, KnownSymbol column)

87− => GroupedBy table column bys where

88−instance {-# OVERLAPPING #-} (KnownSymbol table, KnownSymbol column)

89− => GroupedBy table column ('(table,column) ': bys)

90−instance {-# OVERLAPPABLE #-}

91− ( KnownSymbol table

92− , KnownSymbol column

93− , GroupedBy table column bys

94− ) => GroupedBy table column (tabcol ': bys)

95−

96−-- | `Alias`es are proxies for a type level string or `Symbol`

97−-- and have an `IsLabel` instance so that with @-XOverloadedLabels@

98−--

99−-- >>> :set -XOverloadedLabels

100−-- >>> #foobar :: Alias "foobar"

101−-- Alias

102−data Alias (alias :: Symbol) = Alias

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

104−instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where

105− fromLabel = Alias

106−instance aliases ~ '[alias] => IsLabel alias (NP Alias aliases) where

107− fromLabel = fromLabel SOP.:* Nil

108−-- | >>> printSQL (#jimbob :: Alias "jimbob")

109−-- "jimbob"

110−instance KnownSymbol alias => RenderSQL (Alias alias) where

111− renderSQL = doubleQuoted . fromString . symbolVal

112−

113−-- >>> printSQL (#jimbob :* #kandi :: NP Alias '["jimbob", "kandi"])

114−-- "jimbob", "kandi"

115−instance SOP.All KnownSymbol aliases => RenderSQL (NP Alias aliases) where

116− renderSQL

117− = commaSeparated

118− . SOP.hcollapse

119− . SOP.hcmap (SOP.Proxy @KnownSymbol) (SOP.K . renderSQL)

120−

121−-- | The `As` operator is used to name an expression. `As` is like a demoted

122−-- version of `:::`.

123−--

124−-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)

125−-- As (Just "hello") Alias

126−data Aliased expression aliased where

127− As

128− :: KnownSymbol alias

129− => expression ty

130− -> Alias alias

131− -> Aliased expression (alias ::: ty)

132−deriving instance Show (expression ty)

133− => Show (Aliased expression (alias ::: ty))

134−deriving instance Eq (expression ty)

135− => Eq (Aliased expression (alias ::: ty))

136−deriving instance Ord (expression ty)

137− => Ord (Aliased expression (alias ::: ty))

138−instance (alias0 ~ alias1, alias0 ~ alias2, KnownSymbol alias2)

139− => IsLabel alias0 (Aliased Alias (alias1 ::: alias2)) where

140− fromLabel = fromLabel @alias2 `As` fromLabel @alias1

141−

142−-- | The `Aliasable` class provides a way to scrap your `Nil`s

143−-- in an `NP` list of `Aliased` expressions.

144−class KnownSymbol alias => Aliasable alias expression aliased

145− | aliased -> expression

146− , aliased -> alias

147− where as :: expression -> Alias alias -> aliased

148−instance (KnownSymbol alias, aliased ~ (alias ::: ty)) => Aliasable alias

149− (expression ty)

150− (Aliased expression aliased)

151− where

152− as = As

153−instance (KnownSymbol alias, tys ~ '[alias ::: ty]) => Aliasable alias

154− (expression ty)

155− (NP (Aliased expression) tys)

156− where

157− expression `as` alias = expression `As` alias SOP.:* Nil

158−

159−-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")

160−-- >>> renderAliased renderMaybe (Just (3::Int) `As` #an_int)

161−-- "Just AS \"an_int\""

162−renderAliased

163− :: (forall ty. expression ty -> ByteString)

164− -> Aliased expression aliased

165− -> ByteString

166−renderAliased render (expression `As` alias) =

167− render expression <> " AS " <> renderSQL alias

168−

169−-- | @HasUnique alias fields field@ is a constraint that proves that

170−-- @fields@ is a singleton of @alias ::: field@.

171−type HasUnique alias fields field = fields ~ '[alias ::: field]

172−

173−-- | @Has alias fields field@ is a constraint that proves that

174−-- @fields@ has a field of @alias ::: field@, inferring @field@

175−-- from @alias@ and @fields@.

176−class KnownSymbol alias =>

177− Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)

178− | alias fields -> field where

179−instance {-# OVERLAPPING #-} KnownSymbol alias

180− => Has alias (alias ::: field ': fields) field

181−instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)

182− => Has alias (field' ': fields) field

183−

184−{-| @HasIn fields (alias ::: field)@ is a constraint that proves that

185−@fields@ has a field of @alias ::: field@. It is used in @UPDATE@s to

186−choose which subfields to update.

187−-}

188−class HasIn fields field where

189−instance (Has alias fields field) => HasIn fields (alias ::: field) where

190−

191−-- | `HasAll` extends `Has` to take lists of @aliases@ and @fields@ and infer

192−-- a list of @subfields@.

193−class

194− ( SOP.All KnownSymbol aliases

195− ) => HasAll

196− (aliases :: [Symbol])

197− (fields :: [(Symbol,kind)])

198− (subfields :: [(Symbol,kind)])

199− | aliases fields -> subfields where

200−instance {-# OVERLAPPING #-} HasAll '[] fields '[]

201−instance {-# OVERLAPPABLE #-}

202− (Has alias fields field, HasAll aliases fields subfields)

203− => HasAll (alias ': aliases) fields (alias ::: field ': subfields)

204−

205−-- | Analagous to `IsLabel`, the constraint

206−-- `IsQualified` defines `!` for a column alias qualified

207−-- by a table alias.

208−class IsQualified table column expression where

209− (!) :: Alias table -> Alias column -> expression

210− infixl 9 !

211−instance IsQualified table column (Alias table, Alias column) where (!) = (,)

212−

213−{-| `QualifiedAlias`es enables multi-schema support by allowing a reference

214−to a `Squeal.PostgreSQL.Schema.Table`, `Squeal.PostgreSQL.Schema.Typedef`

215−or `Squeal.PostgreSQL.Schema.View` to be qualified by their schemas. By default,

216−a qualifier of @public@ is provided.

217−

218−>>> :{

219−let

220− alias1 :: QualifiedAlias "sch" "tab"

221− alias1 = #sch ! #tab

222− alias2 :: QualifiedAlias "public" "vw"

223− alias2 = #vw

224−in printSQL alias1 >> printSQL alias2

225−:}

226−"sch"."tab"

227−"vw"

228−-}

229−data QualifiedAlias (qualifier :: Symbol) (alias :: Symbol) = QualifiedAlias

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

231−instance (q ~ q', a ~ a') => IsQualified q a (QualifiedAlias q' a') where

232− _!_ = QualifiedAlias

233−instance (q' ~ "public", a ~ a') => IsLabel a (QualifiedAlias q' a') where

234− fromLabel = QualifiedAlias

235−instance (q0 ~ q1, a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>

236− IsQualified q0 a0 (Aliased (QualifiedAlias q1) (a1 ::: a2)) where

237− _!_ = QualifiedAlias `As` Alias

238−instance (q ~ "public", a0 ~ a1, a1 ~ a2, KnownSymbol a2) =>

239− IsLabel a0 (Aliased (QualifiedAlias q) (a1 ::: a2)) where

240− fromLabel = QualifiedAlias `As` Alias

241−

242−instance (KnownSymbol q, KnownSymbol a)

243− => RenderSQL (QualifiedAlias q a) where

244− renderSQL _ =

245− let

246− qualifier = renderSQL (Alias @q)

247− alias = renderSQL (Alias @a)

248− in

249− if qualifier == "\"public\"" then alias else qualifier <> "." <> alias

squeal-postgresql/src/Squeal/PostgreSQL/Binary.hs+174−635

@@ -5,177 +5,7 @@ Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

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

8+Binary encoding and decoding between Haskell and PostgreSQL types.

9−

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

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

12−to encode Haskell values into statement parameters.

13−

14−Let's see some examples. We'll need some imports

15−

16−>>> import Data.Int (Int16)

17−>>> import Data.Text (Text)

18−>>> import Control.Monad (void)

19−>>> import Control.Monad.IO.Class (liftIO)

20−>>> import Squeal.PostgreSQL

21−

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

23−round trip query.

24−

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

26−>>> instance Generic Row

27−>>> instance HasDatatypeInfo Row

28−>>> :{

29−let

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

31− roundTrip = values_ $

32− parameter @1 int2 `as` #col1 :*

33− parameter @2 text `as` #col2 :*

34− parameter @3 bool `as` #col3

35−:}

36−

37−So long as we can encode the parameters and then decode the result of the query,

38−the input and output should be equal.

39−

40−>>> let input = Row 2 "hi" (Just True)

41−>>> :{

42−withConnection "host=localhost port=5432 dbname=exampledb" $ do

43− result <- runQueryParams roundTrip input

44− Just output <- firstRow result

45− liftIO . print $ input == output

46−:}

47−True

48−

49−In addition to being able to encode and decode basic Haskell types

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

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

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

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

54−create multi-dimensional fixed length arrays.

55−

56−>>> :{

57−data Row = Row

58− { col1 :: VarArray (Vector Int16)

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

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

61− } deriving (Eq, GHC.Generic)

62−:}

63−

64−>>> instance Generic Row

65−>>> instance HasDatatypeInfo Row

66−

67−Once again, we define a simple round trip query.

68−

69−>>> :{

70−let

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

72− roundTrip = values_ $

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

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

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

76−:}

77−

78−>>> :set -XOverloadedLists

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

80−>>> :{

81−withConnection "host=localhost port=5432 dbname=exampledb" $ do

82− result <- runQueryParams roundTrip input

83− Just output <- firstRow result

84− liftIO . print $ input == output

85−:}

86−True

87−

88−Enumerated (enum) types are data types that comprise a static, ordered set of values.

89−They are equivalent to Haskell algebraic data types whose constructors are nullary.

90−An example of an enum type might be the days of the week,

91−or a set of status values for a piece of data.

92−

93−>>> data Schwarma = Beef | Lamb | Chicken deriving (Eq, Show, GHC.Generic)

94−>>> instance Generic Schwarma

95−>>> instance HasDatatypeInfo Schwarma

96−

97−A composite type represents the structure of a row or record;

98−it is essentially just a list of field names and their data types.

99−

100−>>> data Person = Person {name :: Text, age :: Int32} deriving (Eq, Show, GHC.Generic)

101−>>> instance Generic Person

102−>>> instance HasDatatypeInfo Person

103−>>> instance Aeson.FromJSON Person

104−>>> instance Aeson.ToJSON Person

105−

106−We can create the equivalent Postgres types directly from their Haskell types.

107−

108−>>> :{

109−type Schema =

110− '[ "schwarma" ::: 'Typedef (PG (Enumerated Schwarma))

111− , "person" ::: 'Typedef (PG (Composite Person))

112− ]

113−:}

114−

115−>>> :{

116−let

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

118− setup =

119− createTypeEnumFrom @Schwarma #schwarma >>>

120− createTypeCompositeFrom @Person #person

121−:}

122−

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

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

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

126−

127−>>> :{

128−data Row = Row

129− { schwarma :: Enumerated Schwarma

130− , person1 :: Composite Person

131− , person2 :: Json Person

132− } deriving (Eq, GHC.Generic)

133−:}

134−

135−>>> instance Generic Row

136−>>> instance HasDatatypeInfo Row

137−>>> :{

138−let

139− input = Row

140− (Enumerated Chicken)

141− (Composite (Person "Faisal" 24))

142− (Json (Person "Ahmad" 48))

143−:}

144−

145−Once again, define a round trip query.

146−

147−>>> :{

148−let

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

150− roundTrip = values_ $

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

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

153− parameter @3 json `as` #person2

154−:}

155−

156−Finally, we can drop our type definitions.

157−

158−>>> :{

159−let

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

161− teardown = dropType #schwarma >>> dropType #person

162−:}

163−

164−Now let's run it.

165−

166−>>> :{

167−let

168− session = do

169− result <- runQueryParams roundTrip input

170− Just output <- firstRow result

171− liftIO . print $ input == output

172−in

173− withConnection "host=localhost port=5432 dbname=exampledb" $

174− define setup

175− & pqThen session

176− & pqThen (define teardown)

177−:}

178−True

179-}

9-}

180

181{-# LANGUAGE

11{-# LANGUAGE

@@ -184,76 +14,56 @@ True

184 , DeriveFunctor

14 , DeriveFunctor

185 , DeriveGeneric

15 , DeriveGeneric

186 , DeriveTraversable

16 , DeriveTraversable

187− , DefaultSignatures

188 , FlexibleContexts

17 , FlexibleContexts

189 , FlexibleInstances

18 , FlexibleInstances

190− , FunctionalDependencies

191 , GADTs

19 , GADTs

192 , LambdaCase

20 , LambdaCase

193− , OverloadedStrings

194 , MultiParamTypeClasses

21 , MultiParamTypeClasses

195 , ScopedTypeVariables

22 , ScopedTypeVariables

196 , TypeApplications

23 , TypeApplications

197− , TypeFamilies

198 , TypeInType

24 , TypeInType

199 , TypeOperators

25 , TypeOperators

200 , UndecidableInstances

26 , UndecidableInstances

201− , UndecidableSuperClasses

202#-}

27#-}

203

204module Squeal.PostgreSQL.Binary

29module Squeal.PostgreSQL.Binary

205 ( -- * Encoding

30 ( -- * Encoding

206 ToParam (..)

31 ToParam (..)

32+ , ToColumnParam (..)

207 , ToParams (..)

33 , ToParams (..)

208− , ToNullityParam (..)

209− , ToField (..)

210− , ToFixArray (..)

211 -- * Decoding

34 -- * Decoding

212 , FromValue (..)

35 , FromValue (..)

36+ , FromColumnValue (..)

213 , FromRow (..)

37 , FromRow (..)

214− , FromField (..)

215− , FromFixArray (..)

216 -- * Only

38 -- * Only

217 , Only (..)

39 , Only (..)

218− -- * Oid

219− , OidOf (..)

220− , OidOfParam (..)

221− , OidOfField (..)

222 ) where

40 ) where

223

224import BinaryParser

42import BinaryParser

225−import ByteString.StrictBuilder (builderLength, int32BE, int64BE, word32BE)

43+import ByteString.StrictBuilder

226−import Control.Arrow (left)

44+import Data.Aeson hiding (Null)

227−import Control.Monad

228import Data.Int

45import Data.Int

229import Data.Kind

46import Data.Kind

47+import Data.Monoid hiding (All)

230import Data.Scientific

48import Data.Scientific

231import Data.Time

49import Data.Time

232import Data.UUID.Types

50import Data.UUID.Types

233import Data.Vector (Vector)

51import Data.Vector (Vector)

234import Data.Word

52import Data.Word

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

236import Generics.SOP

53import Generics.SOP

237−import Generics.SOP.Record

238import GHC.TypeLits

54import GHC.TypeLits

239import Network.IP.Addr

55import Network.IP.Addr

56+import Text.Read (readMaybe)

240

241−import qualified Data.Aeson as Aeson

58+import qualified Data.ByteString.Lazy as Lazy

242−import qualified Data.ByteString.Lazy as Lazy (ByteString)

243−import qualified Data.ByteString.Lazy as Lazy.ByteString

59+import qualified Data.ByteString as Strict hiding (pack, unpack)

244−import qualified Data.ByteString as Strict (ByteString)

245−import qualified Data.Text.Lazy as Lazy (Text)

60+import qualified Data.Text.Lazy as Lazy

246−import qualified Data.Text as Strict (Text)

247−import qualified Data.Text as Strict.Text

61+import qualified Data.Text as Strict

248import qualified Data.Vector as Vector

62import qualified Data.Vector as Vector

249−import qualified Database.PostgreSQL.LibPQ as LibPQ

250import qualified GHC.Generics as GHC

63import qualified GHC.Generics as GHC

251import qualified PostgreSQL.Binary.Decoding as Decoding

64import qualified PostgreSQL.Binary.Decoding as Decoding

252import qualified PostgreSQL.Binary.Encoding as Encoding

65import qualified PostgreSQL.Binary.Encoding as Encoding

253

254−import Squeal.PostgreSQL.Alias

255−import Squeal.PostgreSQL.List

256−import Squeal.PostgreSQL.PG

257import Squeal.PostgreSQL.Schema

67import Squeal.PostgreSQL.Schema

258

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

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

@@ -277,20 +87,19 @@ class ToParam (x :: Type) (pg :: PGType) where

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

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

278instance ToParam Bool 'PGbool where toParam = K . Encoding.bool

88instance ToParam Bool 'PGbool where toParam = K . Encoding.bool

279instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16

89instance ToParam Int16 'PGint2 where toParam = K . Encoding.int2_int16

90+instance ToParam Word16 'PGint2 where toParam = K . Encoding.int2_word16

280instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32

91instance ToParam Int32 'PGint4 where toParam = K . Encoding.int4_int32

92+instance ToParam Word32 'PGint4 where toParam = K . Encoding.int4_word32

281instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64

93instance ToParam Int64 'PGint8 where toParam = K . Encoding.int8_int64

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

94+instance ToParam Word64 'PGint8 where toParam = K . Encoding.int8_word64

283instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4

95instance ToParam Float 'PGfloat4 where toParam = K . Encoding.float4

284instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8

96instance ToParam Double 'PGfloat8 where toParam = K . Encoding.float8

285instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric

97instance ToParam Scientific 'PGnumeric where toParam = K . Encoding.numeric

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

287instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid

98instance ToParam UUID 'PGuuid where toParam = K . Encoding.uuid

288instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet

99instance ToParam (NetAddr IP) 'PGinet where toParam = K . Encoding.inet

289instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8

100instance ToParam Char ('PGchar 1) where toParam = K . Encoding.char_utf8

290instance ToParam Strict.Text 'PGtext where toParam = K . Encoding.text_strict

101instance ToParam Strict.Text 'PGtext where toParam = K . Encoding.text_strict

291instance ToParam Lazy.Text 'PGtext where toParam = K . Encoding.text_lazy

102instance ToParam Lazy.Text 'PGtext where toParam = K . Encoding.text_lazy

292−instance ToParam String 'PGtext where

293− toParam = K . Encoding.text_strict . Strict.Text.pack

294instance ToParam Strict.ByteString 'PGbytea where

103instance ToParam Strict.ByteString 'PGbytea where

295 toParam = K . Encoding.bytea_strict

104 toParam = K . Encoding.bytea_strict

296instance ToParam Lazy.ByteString 'PGbytea where

105instance ToParam Lazy.ByteString 'PGbytea where

@@ -304,67 +113,33 @@ instance ToParam LocalTime 'PGtimestamp where

304instance ToParam UTCTime 'PGtimestamptz where

113instance ToParam UTCTime 'PGtimestamptz where

305 toParam = K . Encoding.timestamptz_int

114 toParam = K . Encoding.timestamptz_int

306instance ToParam DiffTime 'PGinterval where toParam = K . Encoding.interval_int

115instance ToParam DiffTime 'PGinterval where toParam = K . Encoding.interval_int

307−instance ToParam Aeson.Value 'PGjson where toParam = K . Encoding.json_ast

116+instance ToParam Value 'PGjson where toParam = K . Encoding.json_ast

308−instance ToParam Aeson.Value 'PGjsonb where toParam = K . Encoding.jsonb_ast

117+instance ToParam Value 'PGjsonb where toParam = K . Encoding.jsonb_ast

309−instance Aeson.ToJSON x => ToParam (Json x) 'PGjson where

118+instance (HasOid pg, ToParam x pg)

310− toParam = K . Encoding.json_bytes

311− . Lazy.ByteString.toStrict . Aeson.encode . getJson

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

313− toParam = K . Encoding.jsonb_bytes

314− . Lazy.ByteString.toStrict . Aeson.encode . getJsonb

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

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

317− toParam = K

318− . Encoding.array_foldable

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

320− . getVarArray

321−instance (ToParam x pg, OidOf pg)

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

323− toParam = K

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

325− . getVarArray

326−instance (ToParam x pg, OidOf pg)

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

119+ => ToParam (Vector (Maybe x)) ('PGvararray pg) where

328− toParam = K

329− . Encoding.nullableArray_vector

120+ toParam = K . Encoding.nullableArray_vector

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

121+ (oid @pg) (unK . toParam @x @pg)

331− . getVarArray

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

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

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

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

336instance

122instance

337 ( IsEnumType x

123 ( IsEnumType x

338− , HasDatatypeInfo x

124+ , Show x

339− , LabelsPG x ~ labels

125+ , SameLabels (DatatypeInfoOf x) labels

340− ) => ToParam (Enumerated x) ('PGenum labels) where

126+ ) => ToParam x ('PGenum labels) where

341− toParam =

342− let

343− gshowConstructor :: NP ConstructorInfo xss -> SOP I xss -> String

344− gshowConstructor Nil _ = ""

345− gshowConstructor (constructor :* _) (SOP (Z _)) =

346− constructorName constructor

347− gshowConstructor (_ :* constructors) (SOP (S xs)) =

348− gshowConstructor constructors (SOP xs)

349− in

350− K . Encoding.text_strict

127+ toParam = K . Encoding.text_strict . Strict.pack . show

351− . Strict.Text.pack

352− . gshowConstructor (constructorInfo (datatypeInfo (Proxy @x)))

353− . from

354− . getEnumerated

355instance

128instance

356 ( SListI fields

129 ( SListI fields

357− , IsRecord x xs

130+ , MapMaybes xs

131+ , IsProductType x (Maybes xs)

358− , AllZip ToField xs fields

132+ , AllZip ToAliasedParam xs fields

133+ , SameFields (DatatypeInfoOf x) fields

359− , All OidOfField fields

134+ , All HasAliasedOid fields

360− ) => ToParam (Composite x) ('PGcomposite fields) where

135+ ) => ToParam x ('PGcomposite fields) where

361 toParam =

136 toParam =

362 let

137 let

363

138

364− encoders = htrans (Proxy @ToField) toField

139+ encoders = htrans (Proxy @ToAliasedParam) toAliasedParam

365

140

366 composite

141 composite

367− :: All OidOfField row

142+ :: All HasAliasedOid row

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

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

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

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

370 composite fields = K $

145 composite fields = K $

@@ -381,179 +156,53 @@ instance

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

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

382 let

157 let

383 each

158 each

384− :: OidOfField field

159+ :: HasAliasedOid field

385 => K (Maybe Encoding.Encoding) field

160 => K (Maybe Encoding.Encoding) field

386 -> Encoding.Encoding

161 -> Encoding.Encoding

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

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

388− word32BE (getOid (oidOfField @field))

163+ word32BE (aliasedOid @field)

389 <> case field of

164 <> case field of

390 Nothing -> int64BE (-1)

165 Nothing -> int64BE (-1)

391 Just value ->

166 Just value ->

392 int32BE (fromIntegral (builderLength value))

167 int32BE (fromIntegral (builderLength value))

393 <> value

168 <> value

394 in

169 in

395− hcfoldMap (Proxy @OidOfField) each fields

170+ hcfoldMap (Proxy @HasAliasedOid) each fields

396

171

397 in

172 in

398− composite . encoders . toRecord . getComposite

173+ composite . encoders . unMaybes . unZ . unSOP . from

399−

174+

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

175+class HasAliasedOid (field :: (Symbol, PGType)) where aliasedOid :: Word32

401−--

176+instance HasOid ty => HasAliasedOid (alias ::: ty) where aliasedOid = oid @ty

402−-- >>> :set -XTypeApplications

177+

403−-- >>> oidOf @'PGbool

178+class ToAliasedParam (x :: Type) (field :: (Symbol, PGType)) where

404−-- Oid 16

179+ toAliasedParam :: Maybe x -> K (Maybe Encoding.Encoding) field

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

180+instance ToParam x ty => ToAliasedParam x (alias ::: ty) where

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

181+ toAliasedParam = \case

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

182+ Nothing -> K Nothing

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

183+ Just x -> K . Just . unK $ toParam @x @ty x

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

184+

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

185+-- | A `ToColumnParam` constraint lifts the `ToParam` encoding

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

186+-- of a `Type` to a `ColumnType`, encoding `Maybe`s to `Null`s. You should

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

187+-- not define instances of `ToColumnParam`, just use the provided instances.

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

188+class ToColumnParam (x :: Type) (ty :: NullityType) where

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

189+ -- | >>> toColumnParam @Int16 @('NotNull 'PGint2) 0

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

190+ -- K (Just "\NUL\NUL")

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

191+ --

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

192+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) (Just 0)

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

193+ -- K (Just "\NUL\NUL")

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

194+ --

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

195+ -- >>> toColumnParam @(Maybe Int16) @('Null 'PGint2) Nothing

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

196+ -- K Nothing

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

197+ toColumnParam :: x -> K (Maybe Strict.ByteString) ty

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

198+instance ToParam x pg => ToColumnParam x ('NotNull pg) where

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

199+ toColumnParam = K . Just . Encoding.encodingBytes . unK . toParam @x @pg

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

200+instance ToParam x pg => ToColumnParam (Maybe x) ('Null pg) where

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

201+ toColumnParam = K . fmap (Encoding.encodingBytes . unK . toParam @x @pg)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

508−

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

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

511−

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

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

514− oidOfField :: Oid

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

516− oidOfField = oidOf @ty

517−

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

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

520−class ToNullityParam (x :: Type) (ty :: NullityType) where

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

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

523− toNullityParam = K . Just . unK . toParam @x @pg

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

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

526−

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

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

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

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

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

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

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

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

535−

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

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

538−-- You should not define instances for

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

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

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

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

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

544− . toNullityParam @x @ty

545−instance

546− ( IsProductType product xs

547− , Length xs ~ dim

548− , All ((~) x) xs

549− , ToFixArray x dims ty )

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

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

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

553

202

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

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

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

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

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

205+-- not define instances of `ToParams`. Instead define `Generic` instances

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

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

558class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where

207class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where

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

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

@@ -565,120 +214,79 @@ class SListI tys => ToParams (x :: Type) (tys :: [NullityType]) where

565 -- >>> instance Generic Tuple

214 -- >>> instance Generic Tuple

566 -- >>> toParams @Tuple @Params (Tuple False (Just 0))

215 -- >>> toParams @Tuple @Params (Tuple False (Just 0))

567 -- K (Just "\NUL") :* K (Just "\NUL\NUL") :* Nil

216 -- K (Just "\NUL") :* K (Just "\NUL\NUL") :* Nil

568− toParams :: x -> NP (K (Maybe Encoding.Encoding)) tys

217+ toParams :: x -> NP (K (Maybe Strict.ByteString)) tys

569−instance (SListI tys, IsProductType x xs, AllZip ToNullityParam xs tys)

218+instance (SListI tys, IsProductType x xs, AllZip ToColumnParam xs tys)

570 => ToParams x tys where

219 => ToParams x tys where

571 toParams

220 toParams

572− = htrans (Proxy @ToNullityParam) (toNullityParam . unI)

221+ = htrans (Proxy @ToColumnParam) (toColumnParam . unI)

573 . unZ . unSOP . from

222 . unZ . unSOP . from

574

223

575-- | A `FromValue` constraint gives a parser from the binary format of

224-- | A `FromValue` constraint gives a parser from the binary format of

576-- a PostgreSQL `PGType` into a Haskell `Type`.

225-- a PostgreSQL `PGType` into a Haskell `Type`.

577class FromValue (pg :: PGType) (y :: Type) where

226class FromValue (pg :: PGType) (y :: Type) where

578 -- | >>> newtype Id = Id { getId :: Int16 } deriving Show

227 -- | >>> newtype Id = Id { getId :: Int16 } deriving Show

579− -- >>> instance FromValue 'PGint2 Id where fromValue = Id <$> fromValue @'PGint2

228+ -- >>> instance FromValue 'PGint2 Id where fromValue = fmap Id . fromValue

580− fromValue :: Decoding.Value y

229+ fromValue :: proxy pg -> Decoding.Value y

581−instance FromValue 'PGbool Bool where fromValue = Decoding.bool

230+instance FromValue 'PGbool Bool where fromValue _ = Decoding.bool

582−instance FromValue 'PGint2 Int16 where fromValue = Decoding.int

231+instance FromValue 'PGint2 Int16 where fromValue _ = Decoding.int

583−instance FromValue 'PGint4 Int32 where fromValue = Decoding.int

232+instance FromValue 'PGint4 Int32 where fromValue _ = Decoding.int

584−instance FromValue 'PGint8 Int64 where fromValue = Decoding.int

233+instance FromValue 'PGint8 Int64 where fromValue _ = Decoding.int

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

586−instance FromValue 'PGfloat4 Float where fromValue = Decoding.float4

234+instance FromValue 'PGfloat4 Float where fromValue _ = Decoding.float4

587−instance FromValue 'PGfloat8 Double where fromValue = Decoding.float8

235+instance FromValue 'PGfloat8 Double where fromValue _ = Decoding.float8

588−instance FromValue 'PGnumeric Scientific where fromValue = Decoding.numeric

236+instance FromValue 'PGnumeric Scientific where fromValue _ = Decoding.numeric

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

590−instance FromValue 'PGuuid UUID where fromValue = Decoding.uuid

237+instance FromValue 'PGuuid UUID where fromValue _ = Decoding.uuid

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

238+instance FromValue 'PGinet (NetAddr IP) where fromValue _ = Decoding.inet

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

239+instance FromValue ('PGchar 1) Char where fromValue _ = Decoding.char

593−instance FromValue 'PGtext Strict.Text where fromValue = Decoding.text_strict

240+instance FromValue 'PGtext Strict.Text where fromValue _ = Decoding.text_strict

594−instance FromValue 'PGtext Lazy.Text where fromValue = Decoding.text_lazy

241+instance FromValue 'PGtext Lazy.Text where fromValue _ = Decoding.text_lazy

595−instance FromValue 'PGtext String where

596− fromValue = Strict.Text.unpack <$> Decoding.text_strict

597instance FromValue 'PGbytea Strict.ByteString where

242instance FromValue 'PGbytea Strict.ByteString where

598− fromValue = Decoding.bytea_strict

243+ fromValue _ = Decoding.bytea_strict

599instance FromValue 'PGbytea Lazy.ByteString where

244instance FromValue 'PGbytea Lazy.ByteString where

600− fromValue = Decoding.bytea_lazy

245+ fromValue _ = Decoding.bytea_lazy

601−instance FromValue 'PGdate Day where fromValue = Decoding.date

246+instance FromValue 'PGdate Day where fromValue _ = Decoding.date

602−instance FromValue 'PGtime TimeOfDay where fromValue = Decoding.time_int

247+instance FromValue 'PGtime TimeOfDay where fromValue _ = Decoding.time_int

603instance FromValue 'PGtimetz (TimeOfDay, TimeZone) where

248instance FromValue 'PGtimetz (TimeOfDay, TimeZone) where

604− fromValue = Decoding.timetz_int

249+ fromValue _ = Decoding.timetz_int

605instance FromValue 'PGtimestamp LocalTime where

250instance FromValue 'PGtimestamp LocalTime where

606− fromValue = Decoding.timestamp_int

251+ fromValue _ = Decoding.timestamp_int

607instance FromValue 'PGtimestamptz UTCTime where

252instance FromValue 'PGtimestamptz UTCTime where

608− fromValue = Decoding.timestamptz_int

253+ fromValue _ = Decoding.timestamptz_int

609instance FromValue 'PGinterval DiffTime where

254instance FromValue 'PGinterval DiffTime where

610− fromValue = Decoding.interval_int

255+ fromValue _ = Decoding.interval_int

611−instance FromValue 'PGjson Aeson.Value where fromValue = Decoding.json_ast

256+instance FromValue 'PGjson Value where fromValue _ = Decoding.json_ast

612−instance FromValue 'PGjsonb Aeson.Value where fromValue = Decoding.jsonb_ast

257+instance FromValue 'PGjsonb Value where fromValue _ = Decoding.jsonb_ast

613−instance Aeson.FromJSON x => FromValue 'PGjson (Json x) where

614− fromValue = Json <$>

615− Decoding.json_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)

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

617− fromValue = Jsonb <$>

618− Decoding.jsonb_bytes (left Strict.Text.pack . Aeson.eitherDecodeStrict)

619−instance FromValue pg y

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

258+instance FromValue pg y => FromValue ('PGvararray pg) (Vector (Maybe y)) where

621− fromValue =

259+ fromValue _ = Decoding.array

622− let

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

624− in

625− Decoding.array $ Decoding.dimensionArray rep

260+ (Decoding.dimensionArray Vector.replicateM

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

261+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))

627−instance FromValue pg y

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

629− fromValue =

630− let

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

632− in

633− Decoding.array $ Decoding.dimensionArray rep

634− (fromFixArray @'[] @('Null pg))

635−instance FromValue pg y

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

637− fromValue =

638− let

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

640− in

641− Decoding.array $ Decoding.dimensionArray rep

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

643−instance FromValue pg y

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

645− fromValue =

646− let

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

648− in

649− Decoding.array $ Decoding.dimensionArray rep

650− (fromFixArray @'[] @('Null pg))

651−instance FromFixArray dims ty y

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

262+instance FromValue pg y => FromValue ('PGfixarray n pg) (Vector (Maybe y)) where

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

263+ fromValue _ = Decoding.array

264+ (Decoding.dimensionArray Vector.replicateM

265+ (Decoding.nullableValueArray (fromValue (Proxy @pg))))

654instance

266instance

655 ( IsEnumType y

267 ( IsEnumType y

656− , HasDatatypeInfo y

268+ , Read y

657− , LabelsPG y ~ labels

269+ , SameLabels (DatatypeInfoOf y) labels

658− ) => FromValue ('PGenum labels) (Enumerated y) where

270+ ) => FromValue ('PGenum labels) y where

659− fromValue =

660− let

661− greadConstructor

662− :: All ((~) '[]) xss

663− => NP ConstructorInfo xss

664− -> String

665− -> Maybe (SOP I xss)

666− greadConstructor Nil _ = Nothing

667− greadConstructor (constructor :* constructors) name =

668− if name == constructorName constructor

669− then Just (SOP (Z Nil))

670− else SOP . S . unSOP <$> greadConstructor constructors name

671− in

672− fmap Enumerated

673− . Decoding.enum

271+ fromValue _ = Decoding.enum (readMaybe . Strict.unpack)

674− $ fmap to

675− . greadConstructor (constructorInfo (datatypeInfo (Proxy @y)))

676− . Strict.Text.unpack

677instance

272instance

678− ( FromRow fields y

273+ ( SListI fields

274+ , MapMaybes ys

275+ , IsProductType y (Maybes ys)

276+ , AllZip FromAliasedValue fields ys

277+ , SameFields (DatatypeInfoOf y) fields

679− ) => FromValue ('PGcomposite fields) (Composite y) where

278+ ) => FromValue ('PGcomposite fields) y where

680 fromValue =

279 fromValue =

681 let

280 let

281+ decoders

282+ :: forall pgs zs proxy

283+ . AllZip FromAliasedValue pgs zs

284+ => proxy ('PGcomposite pgs)

285+ -> NP Decoding.Value zs

286+ decoders _ = htrans (Proxy @FromAliasedValue) fromAliasedValue

287+ (hpure Proxy :: NP Proxy pgs)

288+

289+ composite fields = do

682 -- <number of fields: 4 bytes>

290 -- <number of fields: 4 bytes>

683 -- [for each field]

291 -- [for each field]

684 -- <OID of field's type: sizeof(Oid) bytes>

292 -- <OID of field's type: sizeof(Oid) bytes>

@@ -689,133 +297,80 @@ instance

689 -- <value: <length> bytes>

297 -- <value: <length> bytes>

690 -- [end if]

298 -- [end if]

691 -- [end for]

299 -- [end for]

692− composite = Decoding.valueParser $ do

693 unitOfSize 4

300 unitOfSize 4

694− hsequence' $ hpure $ Comp $ do

301+ let

302+ each field = do

695− unitOfSize 4

303+ unitOfSize 4

696− len <- sized 4 Decoding.int

304+ len <- sized 4 Decoding.int

697− if len == -1

698− then return (K Nothing)

305+ if len == -1 then return Nothing else Just <$> sized len field

699− else K . Just <$> bytesOfSize len

306+ htraverse' each fields

700− in

307+

701− fmap Composite (Decoding.fn (fromRow @fields <=< composite))

308+ in fmap (to . SOP . Z . maybes) . composite . decoders

309+

310+class FromAliasedValue (pg :: (Symbol,PGType)) (y :: Type) where

311+ fromAliasedValue :: proxy pg -> Decoding.Value y

312+instance FromValue pg y => FromAliasedValue (alias ::: pg) y where

313+ fromAliasedValue _ = fromValue (Proxy @pg)

702

314

703−-- | A `FromField` constraint lifts the `FromValue` parser

315+-- | A `FromColumnValue` constraint lifts the `FromValue` parser

704-- to a decoding of a @(Symbol, NullityType)@ to a `Type`,

316-- to a decoding of a @(Symbol, NullityType)@ to a `Type`,

705-- decoding `Null`s to `Maybe`s. You should not define instances for

317-- decoding `Null`s to `Maybe`s. You should not define instances for

706−-- `FromField`, just use the provided instances.

318+-- `FromColumnValue`, just use the provided instances.

707−class FromField (pg :: (Symbol, NullityType)) (y :: (Symbol, Type)) where

319+class FromColumnValue (colty :: (Symbol,NullityType)) (y :: Type) where

708− fromField

320+ -- | >>> :set -XTypeOperators -XOverloadedStrings

321+ -- >>> newtype Id = Id { getId :: Int16 } deriving Show

322+ -- >>> instance FromValue 'PGint2 Id where fromValue = fmap Id . fromValue

323+ -- >>> fromColumnValue @("col" ::: 'NotNull 'PGint2) @Id (K (Just "\NUL\SOH"))

324+ -- Id {getId = 1}

325+ --

326+ -- >>> fromColumnValue @("col" ::: 'Null 'PGint2) @(Maybe Id) (K (Just "\NUL\SOH"))

327+ -- Just (Id {getId = 1})

709− :: K (Maybe Strict.ByteString) pg

328+ fromColumnValue :: K (Maybe Strict.ByteString) colty -> y

710− -> (Either Strict.Text :.: P) y

711instance FromValue pg y

329instance FromValue pg y

712− => FromField (column ::: ('NotNull pg)) (column ::: y) where

330+ => FromColumnValue (column ::: ('NotNull pg)) y where

713− fromField = Comp . \case

331+ fromColumnValue = \case

714− K Nothing -> Left "fromField: saw NULL when expecting NOT NULL"

332+ K Nothing -> error "fromColumnValue: saw NULL when expecting NOT NULL"

715− K (Just bytestring) -> P <$>

333+ K (Just bs) ->

334+ let

335+ errOrValue =

716− Decoding.valueParser (fromValue @pg) bytestring

336+ Decoding.valueParser (fromValue @pg @y Proxy) bs

337+ err str = error $ "fromColumnValue: " ++ Strict.unpack str

338+ in

339+ either err id errOrValue

717instance FromValue pg y

340instance FromValue pg y

718− => FromField (column ::: 'Null pg) (column ::: Maybe y) where

341+ => FromColumnValue (column ::: ('Null pg)) (Maybe y) where

719− fromField = Comp . \case

342+ fromColumnValue (K nullOrBytes)

720− K Nothing -> Right $ P Nothing

343+ = either err id

721− K (Just bytestring) -> P . Just <$>

344+ . Decoding.valueParser (fromValue @pg @y Proxy)

722− Decoding.valueParser (fromValue @pg) bytestring

345+ <$> nullOrBytes

723−

346+ where

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

347+ err str = error $ "fromColumnValue: " ++ Strict.unpack str

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

726−-- You should not define instances for

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

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

729− fromFixArray :: Decoding.Array y

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

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

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

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

734−instance

735− ( IsProductType product ys

736− , Length ys ~ dim

737− , All ((~) y) ys

738− , FromFixArray dims ty y )

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

740− fromFixArray =

741− let

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

743− in

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

745

348

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

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

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

350+-- of a `RelationType` into the fields of a record `Type` provided they have

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

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

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

352+-- Instead define `Generic` and `HasDatatypeInfo` instances which in turn

750-- provide `FromRow` instances.

353-- provide `FromRow` instances.

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

354+class SListI results => FromRow (results :: RelationType) y where

752 -- | >>> :set -XOverloadedStrings

355 -- | >>> :set -XOverloadedStrings

753 -- >>> import Data.Text

356 -- >>> import Data.Text

754 -- >>> newtype UserId = UserId { getUserId :: Int16 } deriving Show

357 -- >>> newtype UserId = UserId { getUserId :: Int16 } deriving Show

755− -- >>> instance FromValue 'PGint2 UserId where fromValue = UserId <$> fromValue @'PGint2

358+ -- >>> instance FromValue 'PGint2 UserId where fromValue = fmap UserId . fromValue

756 -- >>> data UserRow = UserRow { userId :: UserId, userName :: Maybe Text } deriving (Show, GHC.Generic)

359 -- >>> data UserRow = UserRow { userId :: UserId, userName :: Maybe Text } deriving (Show, GHC.Generic)

757 -- >>> instance Generic UserRow

360 -- >>> instance Generic UserRow

758 -- >>> instance HasDatatypeInfo UserRow

361 -- >>> instance HasDatatypeInfo UserRow

759 -- >>> type User = '["userId" ::: 'NotNull 'PGint2, "userName" ::: 'Null 'PGtext]

362 -- >>> type User = '["userId" ::: 'NotNull 'PGint2, "userName" ::: 'Null 'PGtext]

760 -- >>> fromRow @User @UserRow (K (Just "\NUL\SOH") :* K (Just "bloodninja") :* Nil)

363 -- >>> fromRow @User @UserRow (K (Just "\NUL\SOH") :* K (Just "bloodninja") :* Nil)

761− -- Right (UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"})

364+ -- UserRow {userId = UserId {getUserId = 1}, userName = Just "bloodninja"}

762− fromRow :: NP (K (Maybe Strict.ByteString)) result -> Either Strict.Text y

365+ fromRow :: NP (K (Maybe Strict.ByteString)) results -> y

763instance

366instance

764− ( SListI result

367+ ( SListI results

765− , IsRecord y ys

368+ , IsProductType y ys

766− , AllZip FromField result ys

369+ , AllZip FromColumnValue results ys

370+ , SameFields (DatatypeInfoOf y) results

767− ) => FromRow result y where

371+ ) => FromRow results y where

768 fromRow

372 fromRow

769− = fmap fromRecord

373+ = to . SOP . Z . htrans (Proxy @FromColumnValue) (I . fromColumnValue)

770− . hsequence'

771− . htrans (Proxy @FromField) fromField

772−------------------------------------------------------

773−-- P records

774−------------------------------------------------------

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

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

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

778−-- instance

779−-- ( row ~ Join row1 row2

780−-- , FromRow row1 hask1

781−-- , FromRow row2 hask2

782−-- , SListI row

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

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

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

786−-- instance

787−-- ( row ~ Join row1 row23

788−-- , FromRow row1 hask1

789−-- , FromRow row23 (hask2, hask3)

790−-- , SListI row

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

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

793−-- (row1, row23) -> do

794−-- hask1 <- fromRow row1

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

796−-- return (hask1, hask2, hask3)

797−-- instance

798−-- ( row ~ Join row1 row234

799−-- , FromRow row1 hask1

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

801−-- , SListI row

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

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

804−-- (row1, row234) -> do

805−-- hask1 <- fromRow row1

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

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

808−-- instance

809−-- ( row ~ Join row1 row2345

810−-- , FromRow row1 hask1

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

812−-- , SListI row

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

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

815−-- (row1, row2345) -> do

816−-- hask1 <- fromRow row1

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

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

819

374

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

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

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

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

@@ -825,24 +380,8 @@ instance

825-- K (Just "foo") :* Nil

380-- K (Just "foo") :* Nil

826--

381--

827-- >>> fromRow @'["fromOnly" ::: 'Null 'PGtext] @(Only (Maybe Text)) (K (Just "bar") :* Nil)

382-- >>> fromRow @'["fromOnly" ::: 'Null 'PGtext] @(Only (Maybe Text)) (K (Just "bar") :* Nil)

828−-- Right (Only {fromOnly = Just "bar"})

383+-- Only {fromOnly = Just "bar"}

829newtype Only x = Only { fromOnly :: x }

384newtype Only x = Only { fromOnly :: x }

830 deriving (Functor,Foldable,Traversable,Eq,Ord,Read,Show,GHC.Generic)

385 deriving (Functor,Foldable,Traversable,Eq,Ord,Read,Show,GHC.Generic)

831instance Generic (Only x)

386instance Generic (Only x)

832instance HasDatatypeInfo (Only x)

387instance HasDatatypeInfo (Only x)

833−

834−foldlN

835− :: All ((~) x) xs

836− => (z -> x -> z) -> z -> NP I xs -> z

837−foldlN f z = \case

838− Nil -> z

839− I x :* xs -> let z' = f z x in seq z' $ foldlN f z' xs

840−

841−replicateMN

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

843− => m x -> m (NP I xs)

844−replicateMN mx = hsequence' $

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

846−

847−getOid :: LibPQ.Oid -> Word32

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

squeal-postgresql/src/Squeal/PostgreSQL/Definition.hs+812−29

@@ -9,74 +9,857 @@ Squeal data definition language.

9-}

11{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

12+ ConstraintKinds

14− , DeriveAnyClass

15 , DeriveGeneric

13 , DeriveGeneric

16− , DerivingStrategies

17 , FlexibleContexts

14 , FlexibleContexts

18 , FlexibleInstances

15 , FlexibleInstances

19 , GADTs

16 , GADTs

17+ , GeneralizedNewtypeDeriving

20 , LambdaCase

18 , LambdaCase

21 , MultiParamTypeClasses

19 , MultiParamTypeClasses

22− , OverloadedLabels

23 , OverloadedStrings

20 , OverloadedStrings

24 , RankNTypes

21 , RankNTypes

25 , ScopedTypeVariables

22 , ScopedTypeVariables

26 , TypeApplications

23 , TypeApplications

27 , TypeInType

24 , TypeInType

28 , TypeOperators

25 , TypeOperators

29− , UndecidableSuperClasses

30− , UndecidableInstances

31#-}

26#-}

33module Squeal.PostgreSQL.Definition

28module Squeal.PostgreSQL.Definition

34− ( -- * Definition

29+ ( -- * Definition

35− Definition (..)

30+ Definition (UnsafeDefinition, renderDefinition)

36 , (>>>)

31 , (>>>)

37− , manipDefinition

32+ -- * Create

33+ , createTable

34+ , createTableIfNotExists

35+ , TableConstraintExpression (..)

36+ , check

37+ , unique

38+ , primaryKey

39+ , foreignKey

40+ , ForeignKeyed

41+ , OnDeleteClause (OnDeleteNoAction, OnDeleteRestrict, OnDeleteCascade)

42+ , renderOnDeleteClause

43+ , OnUpdateClause (OnUpdateNoAction, OnUpdateRestrict, OnUpdateCascade)

44+ , renderOnUpdateClause

45+ -- * Drop

46+ , dropTable

47+ -- * Alter

48+ , alterTable

49+ , alterTableRename

50+ , AlterTable (UnsafeAlterTable, renderAlterTable)

51+ , addConstraint

52+ , dropConstraint

53+ , AddColumn (addColumn)

54+ , dropColumn

55+ , renameColumn

56+ , alterColumn

57+ , AlterColumn (UnsafeAlterColumn, renderAlterColumn)

58+ , setDefault

59+ , dropDefault

60+ , setNotNull

61+ , dropNotNull

62+ , alterType

63+ -- * Views

64+ , createView

65+ , dropView

66+ -- * Types

67+ , createType

68+ , createTypeEnum

69+ , createTypeEnumFromHaskell

70+ , dropType

71+ , ColumnTypeExpression (..)

72+ , default_

73+ , serial2

74+ , smallserial

75+ , serial4

76+ , serial

77+ , serial8

78+ , bigserial

38 ) where

79 ) where

40import Control.Category

81import Control.Category

41import Control.DeepSeq

82import Control.DeepSeq

42import Data.ByteString

83import Data.ByteString

43import Data.Monoid

84import Data.Monoid

85+import GHC.TypeLits

44import Prelude hiding ((.), id)

86import Prelude hiding ((.), id)

88+import qualified Generics.SOP as SOP

46import qualified GHC.Generics as GHC

89import qualified GHC.Generics as GHC

48−import Squeal.PostgreSQL.Manipulation

91+import Squeal.PostgreSQL.Expression

92+import Squeal.PostgreSQL.Query

49import Squeal.PostgreSQL.Render

93import Squeal.PostgreSQL.Render

50import Squeal.PostgreSQL.Schema

94import Squeal.PostgreSQL.Schema

52−-- $setup

53−-- >>> import Squeal.PostgreSQL

54−

55{-----------------------------------------

96{-----------------------------------------

56statements

97statements

57-----------------------------------------}

98-----------------------------------------}

59−-- | A `Definition` is a statement that changes the schemas of the

100+-- | A `Definition` is a statement that changes the schema of the

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

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

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

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

62newtype Definition

103newtype Definition

63− (schemas0 :: SchemasType)

104+ (schema0 :: SchemaType)

64− (schemas1 :: SchemasType)

105+ (schema1 :: SchemaType)

65 = UnsafeDefinition { renderDefinition :: ByteString }

106 = UnsafeDefinition { renderDefinition :: ByteString }

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

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

108

68−instance RenderSQL (Definition schemas0 schemas1) where

69− renderSQL = renderDefinition

70−

71instance Category Definition where

109instance Category Definition where

72 id = UnsafeDefinition ";"

110 id = UnsafeDefinition ";"

73 ddl1 . ddl0 = UnsafeDefinition $

111 ddl1 . ddl0 = UnsafeDefinition $

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

112+ renderDefinition ddl0 <+> renderDefinition ddl1

75−

113+

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

114+{-----------------------------------------

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

115+CREATE statements

78−manipDefinition

116+-----------------------------------------}

79− :: Manipulation '[] schemas '[] '[]

117+

80− -- ^ no input or output

118+-- | `createTable` adds a table to the schema.

81− -> Definition schemas schemas

119+--

82−manipDefinition = UnsafeDefinition . (<> ";") . renderSQL

120+-- >>> :set -XOverloadedLabels

121+-- >>> :{

122+-- renderDefinition $

123+-- createTable #tab ((int & null_) `As` #a :* (real & null_) `As` #b :* Nil) Nil

124+-- :}

125+-- "CREATE TABLE \"tab\" (\"a\" int NULL, \"b\" real NULL);"

126+createTable

127+ :: ( KnownSymbol table

128+ , columns ~ (col ': cols)

129+ , SOP.SListI columns

130+ , SOP.SListI constraints

131+ , schema1 ~ Create table ('Table (constraints :=> columns)) schema0 )

132+ => Alias table -- ^ the name of the table to add

133+ -> NP (Aliased (ColumnTypeExpression schema0)) columns

134+ -- ^ the names and datatype of each column

135+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints

136+ -- ^ constraints that must hold for the table

137+ -> Definition schema0 schema1

138+createTable tab columns constraints = UnsafeDefinition $

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

140+

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

142+-- Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.

143+-- `createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in the `Category` `Definition`.

144+--

145+-- >>> :set -XOverloadedLabels -XTypeApplications

146+-- >>> type Table = '[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGfloat4]

147+-- >>> type Schema = '["tab" ::: 'Table Table]

148+-- >>> :{

149+-- renderDefinition

150+-- (createTableIfNotExists #tab ((int & null_) `As` #a :* (real & null_) `As` #b :* Nil) Nil :: Definition Schema Schema)

151+-- :}

152+-- "CREATE TABLE IF NOT EXISTS \"tab\" (\"a\" int NULL, \"b\" real NULL);"

153+createTableIfNotExists

154+ :: ( Has table schema ('Table (constraints :=> columns))

155+ , SOP.SListI columns

156+ , SOP.SListI constraints )

157+ => Alias table -- ^ the name of the table to add

158+ -> NP (Aliased (ColumnTypeExpression schema)) columns

159+ -- ^ the names and datatype of each column

160+ -> NP (Aliased (TableConstraintExpression schema table)) constraints

161+ -- ^ constraints that must hold for the table

162+ -> Definition schema schema

163+createTableIfNotExists tab columns constraints = UnsafeDefinition $

164+ "CREATE TABLE IF NOT EXISTS"

165+ <+> renderCreation tab columns constraints

166+

167+-- helper function for `createTable` and `createTableIfNotExists`

168+renderCreation

169+ :: ( KnownSymbol table

170+ , SOP.SListI columns

171+ , SOP.SListI constraints )

172+ => Alias table -- ^ the name of the table to add

173+ -> NP (Aliased (ColumnTypeExpression schema0)) columns

174+ -- ^ the names and datatype of each column

175+ -> NP (Aliased (TableConstraintExpression schema1 table)) constraints

176+ -- ^ constraints that must hold for the table

177+ -> ByteString

178+renderCreation tab columns constraints = renderAlias tab

179+ <+> parenthesized

180+ ( renderCommaSeparated renderColumnDef columns

181+ <> ( case constraints of

182+ Nil -> ""

183+ _ -> ", " <>

184+ renderCommaSeparated renderConstraint constraints ) )

185+ <> ";"

186+ where

187+ renderColumnDef :: Aliased (ColumnTypeExpression schema) x -> ByteString

188+ renderColumnDef (ty `As` column) =

189+ renderAlias column <+> renderColumnTypeExpression ty

190+ renderConstraint

191+ :: Aliased (TableConstraintExpression schema columns) constraint

192+ -> ByteString

193+ renderConstraint (constraint `As` alias) =

194+ "CONSTRAINT" <+> renderAlias alias <+> renderTableConstraintExpression constraint

195+

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

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

198+-- too coarse. For example, a column containing a product price should

199+-- probably only accept positive values. But there is no standard data type

200+-- that accepts only positive numbers. Another issue is that you might want

201+-- to constrain column data with respect to other columns or rows.

202+-- For example, in a table containing product information,

203+-- there should be only one row for each product number.

204+-- `TableConstraint`s give you as much control over the data in your tables

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

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

207+-- even if the value came from the default value definition.

208+newtype TableConstraintExpression

209+ (schema :: SchemaType)

210+ (table :: Symbol)

211+ (tableConstraint :: TableConstraint)

212+ = UnsafeTableConstraintExpression

213+ { renderTableConstraintExpression :: ByteString }

214+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

215+

216+-- | A `check` constraint is the most generic `TableConstraint` type.

217+-- It allows you to specify that the value in a certain column must satisfy

218+-- a Boolean (truth-value) expression.

219+--

220+-- >>> :{

221+-- type Schema = '[

222+-- "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[

223+-- "a" ::: 'NoDef :=> 'NotNull 'PGint4,

224+-- "b" ::: 'NoDef :=> 'NotNull 'PGint4

225+-- ])]

226+-- :}

227+--

228+-- >>> :{

229+-- let

230+-- definition :: Definition '[] Schema

231+-- definition = createTable #tab

232+-- ( (int & notNull) `As` #a :*

233+-- (int & notNull) `As` #b :* Nil )

234+-- ( check (#a :* #b :* Nil) (#a .> #b) `As` #inequality :* Nil )

235+-- :}

236+--

237+-- >>> renderDefinition definition

238+-- "CREATE TABLE \"tab\" (\"a\" int NOT NULL, \"b\" int NOT NULL, CONSTRAINT \"inequality\" CHECK ((\"a\" > \"b\")));"

239+check

240+ :: ( Has alias schema ('Table table)

241+ , HasAll aliases (TableToColumns table) subcolumns )

242+ => NP Alias aliases

243+ -> (forall tab. Condition '[tab ::: ColumnsToRelation subcolumns] 'Ungrouped '[])

244+ -> TableConstraintExpression schema alias ('Check aliases)

245+check _cols condition = UnsafeTableConstraintExpression $

246+ "CHECK" <+> parenthesized (renderExpression condition)

247+

248+-- | A `unique` constraint ensure that the data contained in a column,

249+-- or a group of columns, is unique among all the rows in the table.

250+--

251+-- >>> :{

252+-- type Schema = '[

253+-- "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[

254+-- "a" ::: 'NoDef :=> 'Null 'PGint4,

255+-- "b" ::: 'NoDef :=> 'Null 'PGint4

256+-- ])]

257+-- :}

258+--

259+-- >>> :{

260+-- let

261+-- definition :: Definition '[] Schema

262+-- definition = createTable #tab

263+-- ( (int & null_) `As` #a :*

264+-- (int & null_) `As` #b :* Nil )

265+-- ( unique (#a :* #b :* Nil) `As` #uq_a_b :* Nil )

266+-- :}

267+--

268+-- >>> renderDefinition definition

269+-- "CREATE TABLE \"tab\" (\"a\" int NULL, \"b\" int NULL, CONSTRAINT \"uq_a_b\" UNIQUE (\"a\", \"b\"));"

270+unique

271+ :: ( Has alias schema ('Table table)

272+ , HasAll aliases (TableToColumns table) subcolumns )

273+ => NP Alias aliases

274+ -> TableConstraintExpression schema alias ('Unique aliases)

275+unique columns = UnsafeTableConstraintExpression $

276+ "UNIQUE" <+> parenthesized (commaSeparated (renderAliases columns))

277+

278+-- | A `primaryKey` constraint indicates that a column, or group of columns,

279+-- can be used as a unique identifier for rows in the table.

280+-- This requires that the values be both unique and not null.

281+--

282+-- >>> :{

283+-- type Schema = '[

284+-- "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[

285+-- "id" ::: 'Def :=> 'NotNull 'PGint4,

286+-- "name" ::: 'NoDef :=> 'NotNull 'PGtext

287+-- ])]

288+-- :}

289+--

290+-- >>> :{

291+-- let

292+-- definition :: Definition '[] Schema

293+-- definition = createTable #tab

294+-- ( serial `As` #id :*

295+-- (text & notNull) `As` #name :* Nil )

296+-- ( primaryKey #id `As` #pk_id :* Nil )

297+-- :}

298+--

299+-- >>> renderDefinition definition

300+-- "CREATE TABLE \"tab\" (\"id\" serial, \"name\" text NOT NULL, CONSTRAINT \"pk_id\" PRIMARY KEY (\"id\"));"

301+primaryKey

302+ :: ( Has alias schema ('Table table)

303+ , HasAll aliases (TableToColumns table) subcolumns

304+ , AllNotNull subcolumns )

305+ => NP Alias aliases

306+ -> TableConstraintExpression schema alias ('PrimaryKey aliases)

307+primaryKey columns = UnsafeTableConstraintExpression $

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

309+

310+-- | A `foreignKey` specifies that the values in a column

311+-- (or a group of columns) must match the values appearing in some row of

312+-- another table. We say this maintains the referential integrity

313+-- between two related tables.

314+--

315+-- >>> :{

316+-- type Schema =

317+-- '[ "users" ::: 'Table (

318+-- '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

319+-- '[ "id" ::: 'Def :=> 'NotNull 'PGint4

320+-- , "name" ::: 'NoDef :=> 'NotNull 'PGtext

321+-- ])

322+-- , "emails" ::: 'Table (

323+-- '[ "pk_emails" ::: 'PrimaryKey '["id"]

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

325+-- ] :=>

326+-- '[ "id" ::: 'Def :=> 'NotNull 'PGint4

327+-- , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

328+-- , "email" ::: 'NoDef :=> 'Null 'PGtext

329+-- ])

330+-- ]

331+-- :}

332+--

333+-- >>> :{

334+-- let

335+-- setup :: Definition '[] Schema

336+-- setup =

337+-- createTable #users

338+-- ( serial `As` #id :*

339+-- (text & notNull) `As` #name :* Nil )

340+-- ( primaryKey #id `As` #pk_users :* Nil ) >>>

341+-- createTable #emails

342+-- ( serial `As` #id :*

343+-- (int & notNull) `As` #user_id :*

344+-- (text & null_) `As` #email :* Nil )

345+-- ( primaryKey #id `As` #pk_emails :*

346+-- foreignKey #user_id #users #id

347+-- OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )

348+-- in renderDefinition setup

349+-- :}

350+-- "CREATE TABLE \"users\" (\"id\" serial, \"name\" text NOT NULL, CONSTRAINT \"pk_users\" PRIMARY KEY (\"id\")); 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);"

351+--

352+-- A `foreignKey` can even be a table self-reference.

353+--

354+-- >>> :{

355+-- type Schema =

356+-- '[ "employees" ::: 'Table (

357+-- '[ "employees_pk" ::: 'PrimaryKey '["id"]

358+-- , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]

359+-- ] :=>

360+-- '[ "id" ::: 'Def :=> 'NotNull 'PGint4

361+-- , "name" ::: 'NoDef :=> 'NotNull 'PGtext

362+-- , "employer_id" ::: 'NoDef :=> 'Null 'PGint4

363+-- ])

364+-- ]

365+-- :}

366+--

367+-- >>> :{

368+-- let

369+-- setup :: Definition '[] Schema

370+-- setup =

371+-- createTable #employees

372+-- ( serial `As` #id :*

373+-- (text & notNull) `As` #name :*

374+-- (integer & null_) `As` #employer_id :* Nil )

375+-- ( primaryKey #id `As` #employees_pk :*

376+-- foreignKey #employer_id #employees #id

377+-- OnDeleteCascade OnUpdateCascade `As` #employees_employer_fk :* Nil )

378+-- in renderDefinition setup

379+-- :}

380+-- "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);"

381+--

382+foreignKey

383+ :: (ForeignKeyed schema child parent

384+ table reftable

385+ columns refcolumns

386+ constraints cols

387+ reftys tys )

388+ => NP Alias columns

389+ -- ^ column or columns in the table

390+ -> Alias parent

391+ -- ^ reference table

392+ -> NP Alias refcolumns

393+ -- ^ reference column or columns in the reference table

394+ -> OnDeleteClause

395+ -- ^ what to do when reference is deleted

396+ -> OnUpdateClause

397+ -- ^ what to do when reference is updated

398+ -> TableConstraintExpression schema child

399+ ('ForeignKey columns parent refcolumns)

400+foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $

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

402+ <+> "REFERENCES" <+> renderAlias parent

403+ <+> parenthesized (commaSeparated (renderAliases refs))

404+ <+> renderOnDeleteClause ondel

405+ <+> renderOnUpdateClause onupd

406+

407+type ForeignKeyed schema

408+ child parent

409+ table reftable

410+ columns refcolumns

411+ constraints cols

412+ reftys tys =

413+ ( Has child schema ('Table table)

414+ , Has parent schema ('Table reftable)

415+ , HasAll columns (TableToColumns table) tys

416+ , reftable ~ (constraints :=> cols)

417+ , HasAll refcolumns cols reftys

418+ , SOP.AllZip SamePGType tys reftys

419+ , Uniquely refcolumns constraints )

420+

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

422+data OnDeleteClause

423+ = OnDeleteNoAction

424+ -- ^ if any referencing rows still exist when the constraint is checked,

425+ -- an error is raised

426+ | OnDeleteRestrict -- ^ prevents deletion of a referenced row

427+ | OnDeleteCascade

428+ -- ^ specifies that when a referenced row is deleted,

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

430+ deriving (GHC.Generic,Show,Eq,Ord)

431+instance NFData OnDeleteClause

432+

433+-- | Render `OnDeleteClause`.

434+renderOnDeleteClause :: OnDeleteClause -> ByteString

435+renderOnDeleteClause = \case

436+ OnDeleteNoAction -> "ON DELETE NO ACTION"

437+ OnDeleteRestrict -> "ON DELETE RESTRICT"

438+ OnDeleteCascade -> "ON DELETE CASCADE"

439+

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

441+-- when a referenced column is changed (updated).

442+data OnUpdateClause

443+ = OnUpdateNoAction

444+ -- ^ if any referencing rows has not changed when the constraint is checked,

445+ -- an error is raised

446+ | OnUpdateRestrict -- ^ prevents update of a referenced row

447+ | OnUpdateCascade

448+ -- ^ the updated values of the referenced column(s) should be copied

449+ -- into the referencing row(s)

450+ deriving (GHC.Generic,Show,Eq,Ord)

451+instance NFData OnUpdateClause

452+

453+-- | Render `OnUpdateClause`.

454+renderOnUpdateClause :: OnUpdateClause -> ByteString

455+renderOnUpdateClause = \case

456+ OnUpdateNoAction -> "ON UPDATE NO ACTION"

457+ OnUpdateRestrict -> "ON UPDATE RESTRICT"

458+ OnUpdateCascade -> "ON UPDATE CASCADE"

459+

460+{-----------------------------------------

461+DROP statements

462+-----------------------------------------}

463+

464+-- | `dropTable` removes a table from the schema.

465+--

466+-- >>> :{

467+-- let

468+-- definition :: Definition '["muh_table" ::: 'Table t] '[]

469+-- definition = dropTable #muh_table

470+-- :}

471+--

472+-- >>> renderDefinition definition

473+-- "DROP TABLE \"muh_table\";"

474+dropTable

475+ :: Has table schema ('Table t)

476+ => Alias table -- ^ table to remove

477+ -> Definition schema (Drop table schema)

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

479+

480+{-----------------------------------------

481+ALTER statements

482+-----------------------------------------}

483+

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

485+alterTable

486+ :: KnownSymbol alias

487+ => Alias alias -- ^ table to alter

488+ -> AlterTable alias table schema -- ^ alteration to perform

489+ -> Definition schema (Alter alias ('Table table) schema)

490+alterTable tab alteration = UnsafeDefinition $

491+ "ALTER TABLE"

492+ <+> renderAlias tab

493+ <+> renderAlterTable alteration

494+ <> ";"

495+

496+-- | `alterTableRename` changes the name of a table from the schema.

497+--

498+-- >>> renderDefinition $ alterTableRename #foo #bar

499+-- "ALTER TABLE \"foo\" RENAME TO \"bar\";"

500+alterTableRename

501+ :: (KnownSymbol table0, KnownSymbol table1)

502+ => Alias table0 -- ^ table to rename

503+ -> Alias table1 -- ^ what to rename it

504+ -> Definition schema (Rename table0 table1 schema)

505+alterTableRename table0 table1 = UnsafeDefinition $

506+ "ALTER TABLE" <+> renderAlias table0

507+ <+> "RENAME TO" <+> renderAlias table1 <> ";"

508+

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

510+-- of a table.

511+newtype AlterTable

512+ (alias :: Symbol)

513+ (table :: TableType)

514+ (schema :: SchemaType) =

515+ UnsafeAlterTable {renderAlterTable :: ByteString}

516+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

517+

518+-- | An `addConstraint` adds a table constraint.

519+--

520+-- >>> :{

521+-- let

522+-- definition :: Definition

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

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

525+-- definition = alterTable #tab (addConstraint #positive (check (#col :* Nil) (#col .> 0)))

526+-- in renderDefinition definition

527+-- :}

528+-- "ALTER TABLE \"tab\" ADD CONSTRAINT \"positive\" CHECK ((\"col\" > 0));"

529+addConstraint

530+ :: ( KnownSymbol alias

531+ , Has tab schema ('Table table0)

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

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

534+ => Alias alias

535+ -> TableConstraintExpression schema tab constraint

536+ -- ^ constraint to add

537+ -> AlterTable tab table1 schema

538+addConstraint alias constraint = UnsafeAlterTable $

539+ "ADD" <+> "CONSTRAINT" <+> renderAlias alias

540+ <+> renderTableConstraintExpression constraint

541+

542+-- | A `dropConstraint` drops a table constraint.

543+--

544+-- >>> :{

545+-- let

546+-- definition :: Definition

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

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

549+-- definition = alterTable #tab (dropConstraint #positive)

550+-- in renderDefinition definition

551+-- :}

552+-- "ALTER TABLE \"tab\" DROP CONSTRAINT \"positive\";"

553+dropConstraint

554+ :: ( KnownSymbol constraint

555+ , Has tab schema ('Table table0)

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

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

558+ => Alias constraint

559+ -- ^ constraint to drop

560+ -> AlterTable tab table1 schema

561+dropConstraint constraint = UnsafeAlterTable $

562+ "DROP" <+> "CONSTRAINT" <+> renderAlias constraint

563+

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

565+class AddColumn ty where

566+ -- | `addColumn` adds a new column, initially filled with whatever

567+ -- default value is given or with @NULL@.

568+ --

569+ -- >>> :{

570+ -- let

571+ -- definition :: Definition

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

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

574+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

576+ -- definition = alterTable #tab (addColumn #col2 (text & null_ & default_ "foo"))

577+ -- in renderDefinition definition

578+ -- :}

579+ -- "ALTER TABLE \"tab\" ADD COLUMN \"col2\" text NULL DEFAULT E'foo';"

580+ --

581+ -- >>> :{

582+ -- let

583+ -- definition :: Definition

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

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

586+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

588+ -- definition = alterTable #tab (addColumn #col2 (text & null_))

589+ -- in renderDefinition definition

590+ -- :}

591+ -- "ALTER TABLE \"tab\" ADD COLUMN \"col2\" text NULL;"

592+ addColumn

593+ :: ( KnownSymbol column

594+ , Has tab schema ('Table table0)

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

596+ , table1 ~ (constraints :=> Create column ty columns) )

597+ => Alias column -- ^ column to add

598+ -> ColumnTypeExpression schema ty -- ^ type of the new column

599+ -> AlterTable tab table1 schema

600+ addColumn column ty = UnsafeAlterTable $

601+ "ADD COLUMN" <+> renderAlias column <+> renderColumnTypeExpression ty

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

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

604+

605+-- | A `dropColumn` removes a column. Whatever data was in the column

606+-- disappears. Table constraints involving the column are dropped, too.

607+-- However, if the column is referenced by a foreign key constraint of

608+-- another table, PostgreSQL will not silently drop that constraint.

609+--

610+-- >>> :{

611+-- let

612+-- definition :: Definition

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

614+-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4

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

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

617+-- definition = alterTable #tab (dropColumn #col2)

618+-- in renderDefinition definition

619+-- :}

620+-- "ALTER TABLE \"tab\" DROP COLUMN \"col2\";"

621+dropColumn

622+ :: ( KnownSymbol column

623+ , Has tab schema ('Table table0)

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

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

626+ => Alias column -- ^ column to remove

627+ -> AlterTable tab table1 schema

628+dropColumn column = UnsafeAlterTable $

629+ "DROP COLUMN" <+> renderAlias column

630+

631+-- | A `renameColumn` renames a column.

632+--

633+-- >>> :{

634+-- let

635+-- definition :: Definition

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

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

638+-- definition = alterTable #tab (renameColumn #foo #bar)

639+-- in renderDefinition definition

640+-- :}

641+-- "ALTER TABLE \"tab\" RENAME COLUMN \"foo\" TO \"bar\";"

642+renameColumn

643+ :: ( KnownSymbol column0

644+ , KnownSymbol column1

645+ , Has tab schema ('Table table0)

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

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

648+ => Alias column0 -- ^ column to rename

649+ -> Alias column1 -- ^ what to rename the column

650+ -> AlterTable tab table1 schema

651+renameColumn column0 column1 = UnsafeAlterTable $

652+ "RENAME COLUMN" <+> renderAlias column0 <+> "TO" <+> renderAlias column1

653+

654+-- | An `alterColumn` alters a single column.

655+alterColumn

656+ :: ( KnownSymbol column

657+ , Has tab schema ('Table table0)

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

659+ , Has column columns ty0

660+ , tables1 ~ (constraints :=> Alter column ty1 columns))

661+ => Alias column -- ^ column to alter

662+ -> AlterColumn schema ty0 ty1 -- ^ alteration to perform

663+ -> AlterTable tab table1 schema

664+alterColumn column alteration = UnsafeAlterTable $

665+ "ALTER COLUMN" <+> renderAlias column <+> renderAlterColumn alteration

666+

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

668+newtype AlterColumn (schema :: SchemaType) (ty0 :: ColumnType) (ty1 :: ColumnType) =

669+ UnsafeAlterColumn {renderAlterColumn :: ByteString}

670+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

671+

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

673+-- affect any existing rows in the table, it just changes the default for

674+-- future insert and update commands.

675+--

676+-- >>> :{

677+-- let

678+-- definition :: Definition

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

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

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

682+-- in renderDefinition definition

683+-- :}

684+-- "ALTER TABLE \"tab\" ALTER COLUMN \"col\" SET DEFAULT 5;"

685+setDefault

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

687+ -> AlterColumn schema (constraint :=> ty) ('Def :=> ty)

688+setDefault expression = UnsafeAlterColumn $

689+ "SET DEFAULT" <+> renderExpression expression

690+

691+-- | A `dropDefault` removes any default value for a column.

692+--

693+-- >>> :{

694+-- let

695+-- definition :: Definition

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

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

698+-- definition = alterTable #tab (alterColumn #col dropDefault)

699+-- in renderDefinition definition

700+-- :}

701+-- "ALTER TABLE \"tab\" ALTER COLUMN \"col\" DROP DEFAULT;"

702+dropDefault :: AlterColumn schema ('Def :=> ty) ('NoDef :=> ty)

703+dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

704+

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

706+-- The constraint will be checked immediately, so the table data must satisfy

707+-- the constraint before it can be added.

708+--

709+-- >>> :{

710+-- let

711+-- definition :: Definition

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

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

714+-- definition = alterTable #tab (alterColumn #col setNotNull)

715+-- in renderDefinition definition

716+-- :}

717+-- "ALTER TABLE \"tab\" ALTER COLUMN \"col\" SET NOT NULL;"

718+setNotNull

719+ :: AlterColumn schema (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)

720+setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

721+

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

723+--

724+-- >>> :{

725+-- let

726+-- definition :: Definition

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

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

729+-- definition = alterTable #tab (alterColumn #col dropNotNull)

730+-- in renderDefinition definition

731+-- :}

732+-- "ALTER TABLE \"tab\" ALTER COLUMN \"col\" DROP NOT NULL;"

733+dropNotNull

734+ :: AlterColumn schema (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)

735+dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

736+

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

738+-- This will succeed only if each existing entry in the column can be

739+-- converted to the new type by an implicit cast.

740+--

741+-- >>> :{

742+-- let

743+-- definition :: Definition

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

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

746+-- definition =

747+-- alterTable #tab (alterColumn #col (alterType (numeric & notNull)))

748+-- in renderDefinition definition

749+-- :}

750+-- "ALTER TABLE \"tab\" ALTER COLUMN \"col\" TYPE numeric NOT NULL;"

751+alterType :: ColumnTypeExpression schema ty -> AlterColumn schema ty0 ty

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

753+

754+-- | create a view...

755+-- >>> :{

756+-- let

757+-- definition :: Definition

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

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

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

761+-- definition =

762+-- createView #bc (select (#b `As` #b :* #c `As` #c :* Nil) (from (table (#abc `As` #abc))))

763+-- in renderDefinition definition

764+-- :}

765+-- "CREATE VIEW \"bc\" AS SELECT \"b\" AS \"b\", \"c\" AS \"c\" FROM \"abc\" AS \"abc\";"

766+createView

767+ :: KnownSymbol view

768+ => Alias view -- ^ the name of the table to add

769+ -> Query schema '[] relation

770+ -- ^ query

771+ -> Definition schema (Create view ('View relation) schema)

772+createView alias query = UnsafeDefinition $

773+ "CREATE" <+> "VIEW" <+> renderAlias alias <+> "AS"

774+ <+> renderQuery query <> ";"

775+

776+dropView

777+ :: Has view schema ('View v)

778+ => Alias view -- ^ view to remove

779+ -> Definition schema (Drop view schema)

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

781+

782+createTypeEnum

783+ :: (KnownSymbol enum, SOP.All KnownSymbol labels)

784+ => Alias enum

785+ -> NP PGlabel labels

786+ -> Definition schema (Create enum ('Typedef ('PGenum labels)) schema)

787+createTypeEnum enum labels = UnsafeDefinition $

788+ "CREATE" <+> "TYPE" <+> renderAlias enum <+> "AS" <+>

789+ parenthesized (commaSeparated (renderLabels labels)) <> ";"

790+

791+createTypeEnumFromHaskell

792+ :: forall enum labels hask proxy schema

793+ . ( KnownSymbol enum

794+ , SOP.All KnownSymbol labels

795+ , SOP.IsEnumType hask

796+ , labels ~ DatatypeLabels (SOP.DatatypeInfoOf hask) )

797+ => Alias enum

798+ -> proxy hask

799+ -> Definition schema (Create enum ('Typedef ('PGenum labels)) schema)

800+createTypeEnumFromHaskell enum _ = createTypeEnum enum

801+ (SOP.hpure label :: NP PGlabel labels)

802+

803+createType

804+ :: (KnownSymbol comp, SOP.SListI fields)

805+ => Alias comp

806+ -> NP (Aliased TypeExpression) fields

807+ -> Definition schema (Create comp ('Typedef ('PGcomposite fields)) schema)

808+createType comp fields = UnsafeDefinition $

809+ "CREATE" <+> "TYPE" <+> renderAlias comp <+> "AS" <+> parenthesized

810+ (renderCommaSeparated (renderAliasedAs renderTypeExpression) fields) <> ";"

811+

812+dropType

813+ :: Has tydef schema ('Typedef ty)

814+ => Alias tydef

815+ -> Definition schema (Drop tydef schema)

816+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderAlias tydef <> ";"

817+

818+-- | `ColumnTypeExpression`s are used in `createTable` commands.

819+newtype ColumnTypeExpression (schema :: SchemaType) (ty :: ColumnType)

820+ = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }

821+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

822+

823+instance (Has alias schema ('Typedef ty))

824+ => IsLabel alias (ColumnTypeExpression schema ('NoDef :=> 'NotNull ty)) where

825+ fromLabel = UnsafeColumnTypeExpression (renderAlias (fromLabel @alias))

826+

827+instance HasNull

828+ ( TypeExpression ty

829+ -> ColumnTypeExpression schema ('NoDef :=> 'Null ty) ) where

830+ null_ ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NULL"

831+

832+instance HasNotNull

833+ ( TypeExpression ty

834+ ->

835+ ColumnTypeExpression schema (def :=> 'NotNull ty) ) where

836+ -- | used in `createTable` commands as a column constraint to ensure

837+ -- @NULL@ is not present

838+ notNull ty = UnsafeColumnTypeExpression $ renderTypeExpression ty <+> "NOT NULL"

839+

840+-- | used in `createTable` commands as a column constraint to give a default

841+default_

842+ :: Expression '[] 'Ungrouped '[] ty

843+ -> ColumnTypeExpression schema ('NoDef :=> ty)

844+ -> ColumnTypeExpression schema ('Def :=> ty)

845+default_ x ty = UnsafeColumnTypeExpression $

846+ renderColumnTypeExpression ty <+> "DEFAULT" <+> renderExpression x

847+

848+-- | not a true type, but merely a notational convenience for creating

849+-- unique identifier columns with type `'PGint2`

850+serial2, smallserial

851+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint2)

852+serial2 = UnsafeColumnTypeExpression "serial2"

853+smallserial = UnsafeColumnTypeExpression "smallserial"

854+-- | not a true type, but merely a notational convenience for creating

855+-- unique identifier columns with type `'PGint4`

856+serial4, serial

857+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint4)

858+serial4 = UnsafeColumnTypeExpression "serial4"

859+serial = UnsafeColumnTypeExpression "serial"

860+-- | not a true type, but merely a notational convenience for creating

861+-- unique identifier columns with type `'PGint8`

862+serial8, bigserial

863+ :: ColumnTypeExpression schema ('Def :=> 'NotNull 'PGint8)

864+serial8 = UnsafeColumnTypeExpression "serial8"

865+bigserial = UnsafeColumnTypeExpression "bigserial"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Function.hsdeleted−238

@@ -1,238 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Function

3−Description: Create and drop function and operator definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create and drop function and operator definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Function

33− ( createFunction

34− , createOrReplaceFunction

35− , createSetFunction

36− , createOrReplaceSetFunction

37− , createBinaryOp

38− , createLeftOp

39− , createRightOp

40− , dropFunction

41− , dropFunctionIfExists

42− , dropOperator

43− , dropOperatorIfExists

44− , FunctionDefinition(..)

45− , languageSqlExpr

46− , languageSqlQuery

47− ) where

48−

49−import Control.DeepSeq

50−import Data.ByteString

51−import GHC.TypeLits

52−

53−import qualified Generics.SOP as SOP

54−import qualified GHC.Generics as GHC

55−

56−import Squeal.PostgreSQL.Alias

57−import Squeal.PostgreSQL.Definition

58−import Squeal.PostgreSQL.Expression

59−import Squeal.PostgreSQL.Expression.Type

60−import Squeal.PostgreSQL.List

61−import Squeal.PostgreSQL.Query

62−import Squeal.PostgreSQL.Render

63−import Squeal.PostgreSQL.Schema

64−

65−-- $setup

66−-- >>> import Squeal.PostgreSQL

67−

68−createFunction

69− :: ( Has sch schemas schema

70− , KnownSymbol fun

71− , SOP.SListI args )

72− => QualifiedAlias sch fun

73− -> NP (TypeExpression schemas) args

74− -> TypeExpression schemas ret

75− -> FunctionDefinition schemas args ('Returns ret)

76− -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'Returns ret)) schema) schemas)

77−createFunction fun args ret fundef = UnsafeDefinition $

78− "CREATE" <+> "FUNCTION" <+> renderSQL fun

79− <+> parenthesized (renderCommaSeparated renderSQL args)

80− <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"

81−

82−createOrReplaceFunction

83− :: ( Has sch schemas schema

84− , KnownSymbol fun

85− , SOP.SListI args )

86− => QualifiedAlias sch fun

87− -> NP (TypeExpression schemas) args

88− -> TypeExpression schemas ret

89− -> FunctionDefinition schemas args ('Returns ret)

90− -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'Returns ret)) schema) schemas)

91−createOrReplaceFunction fun args ret fundef = UnsafeDefinition $

92− "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun

93− <+> parenthesized (renderCommaSeparated renderSQL args)

94− <+> "RETURNS" <+> renderSQL ret <+> renderSQL fundef <> ";"

95−

96−languageSqlExpr

97− :: Expression '[] '[] 'Ungrouped schemas args '[] ret

98− -> FunctionDefinition schemas args ('Returns ret)

99−languageSqlExpr expr = UnsafeFunctionDefinition $

100− "language sql as"

101− <+> "$$" <+> renderSQL (values_ (expr `as` #ret)) <+> "$$"

102−

103−languageSqlQuery

104− :: Query '[] '[] schemas args rets

105− -> FunctionDefinition schemas args ('ReturnsTable rets)

106−languageSqlQuery qry = UnsafeFunctionDefinition $

107− "language sql as" <+> "$$" <+> renderSQL qry <+> "$$"

108−

109−createSetFunction

110− :: ( Has sch schemas schema

111− , KnownSymbol fun

112− , SOP.SListI args

113− , SOP.SListI rets )

114− => QualifiedAlias sch fun

115− -> NP (TypeExpression schemas) args

116− -> NP (Aliased (TypeExpression schemas)) rets

117− -> FunctionDefinition schemas args ('ReturnsTable rets)

118− -> Definition schemas (Alter sch (Create fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)

119−createSetFunction fun args rets fundef = UnsafeDefinition $

120− "CREATE" <+> "FUNCTION" <+> renderSQL fun

121− <+> parenthesized (renderCommaSeparated renderSQL args)

122− <+> "RETURNS" <+> "TABLE"

123− <+> parenthesized (renderCommaSeparated renderRet rets)

124− <+> renderSQL fundef <> ";"

125− where

126− renderRet :: Aliased (TypeExpression s) r -> ByteString

127− renderRet (ty `As` col) = renderSQL col <+> renderSQL ty

128−

129−createOrReplaceSetFunction

130− :: ( Has sch schemas schema

131− , KnownSymbol fun

132− , SOP.SListI args

133− , SOP.SListI rets )

134− => QualifiedAlias sch fun

135− -> NP (TypeExpression schemas) args

136− -> NP (Aliased (TypeExpression schemas)) rets

137− -> FunctionDefinition schemas args ('ReturnsTable rets)

138− -> Definition schemas (Alter sch (CreateOrReplace fun ('Function (args :=> 'ReturnsTable rets)) schema) schemas)

139−createOrReplaceSetFunction fun args rets fundef = UnsafeDefinition $

140− "CREATE" <+> "OR" <+> "REPLACE" <+> "FUNCTION" <+> renderSQL fun

141− <+> parenthesized (renderCommaSeparated renderSQL args)

142− <+> "RETURNS" <+> "TABLE"

143− <+> parenthesized (renderCommaSeparated renderRet rets)

144− <+> renderSQL fundef <> ";"

145− where

146− renderRet :: Aliased (TypeExpression s) r -> ByteString

147− renderRet (ty `As` col) = renderSQL col <+> renderSQL ty

148−

149−createBinaryOp

150− :: forall op fun sch schemas schema x y z.

151− ( Has sch schemas schema

152− , Has fun schema ('Function ('[x,y] :=> 'Returns z))

153− , KnownSymbol op )

154− => QualifiedAlias sch fun

155− -> TypeExpression schemas x

156− -> TypeExpression schemas y

157− -> Definition schemas

158− (Alter sch (Create op ('Operator ('BinaryOp x y z)) schema) schemas)

159−createBinaryOp fun x y = UnsafeDefinition $

160− "CREATE" <+> "OPERATOR" <+> renderSymbol @op

161− <+> parenthesized (commaSeparated opdef)

162− where

163− opdef =

164− [ "FUNCTION" <+> "=" <+> renderSQL fun

165− , "LEFTARG" <+> "=" <+> renderSQL x

166− , "RIGHTARG" <+> "=" <+> renderSQL y ]

167−

168−createLeftOp

169− :: forall op fun sch schemas schema x y.

170− ( Has sch schemas schema

171− , Has fun schema ('Function ('[x] :=> 'Returns y))

172− , KnownSymbol op )

173− => QualifiedAlias sch fun

174− -> TypeExpression schemas x

175− -> Definition schemas

176− (Alter sch (Create op ('Operator ('LeftOp x y)) schema) schemas)

177−createLeftOp fun x = UnsafeDefinition $

178− "CREATE" <+> "OPERATOR" <+> renderSymbol @op

179− <+> parenthesized (commaSeparated opdef)

180− where

181− opdef =

182− [ "FUNCTION" <+> "=" <+> renderSQL fun

183− , "RIGHTARG" <+> "=" <+> renderSQL x ]

184−

185−createRightOp

186− :: forall op fun sch schemas schema x y.

187− ( Has sch schemas schema

188− , Has fun schema ('Function ('[x] :=> 'Returns y))

189− , KnownSymbol op )

190− => QualifiedAlias sch fun

191− -> TypeExpression schemas x

192− -> Definition schemas

193− (Alter sch (Create op ('Operator ('RightOp x y)) schema) schemas)

194−createRightOp fun x = UnsafeDefinition $

195− "CREATE" <+> "OPERATOR" <+> renderSymbol @op

196− <+> parenthesized (commaSeparated opdef)

197− where

198− opdef =

199− [ "FUNCTION" <+> "=" <+> renderSQL fun

200− , "LEFTARG" <+> "=" <+> renderSQL x ]

201−

202−dropFunction

203− :: (Has sch schemas schema, KnownSymbol fun)

204− => QualifiedAlias sch fun

205− -- ^ name of the user defined function

206− -> Definition schemas (Alter sch (DropSchemum fun 'Function schema) schemas)

207−dropFunction fun = UnsafeDefinition $

208− "DROP" <+> "FUNCTION" <+> renderSQL fun <> ";"

209−

210−dropFunctionIfExists

211− :: (Has sch schemas schema, KnownSymbol fun)

212− => QualifiedAlias sch fun

213− -- ^ name of the user defined function

214− -> Definition schemas (Alter sch (DropSchemumIfExists fun 'Function schema) schemas)

215−dropFunctionIfExists fun = UnsafeDefinition $

216− "DROP FUNCTION IF EXISTS" <+> renderSQL fun <> ";"

217−

218−dropOperator

219− :: (Has sch schemas schema, KnownSymbol op)

220− => QualifiedAlias sch op

221− -- ^ name of the user defined operator

222− -> Definition schemas (Alter sch (DropSchemum op 'Operator schema) schemas)

223−dropOperator op = UnsafeDefinition $

224− "DROP" <+> "OPERATOR" <+> renderSQL op <> ";"

225−

226−dropOperatorIfExists

227− :: (Has sch schemas schema, KnownSymbol op)

228− => QualifiedAlias sch op

229− -- ^ name of the user defined operator

230− -> Definition schemas (Alter sch (DropSchemumIfExists op 'Operator schema) schemas)

231−dropOperatorIfExists op = UnsafeDefinition $

232− "DROP OPERATOR IF EXISTS" <+> renderSQL op <> ";"

233−

234−newtype FunctionDefinition schemas args ret = UnsafeFunctionDefinition

235− { renderFunctionDefinition :: ByteString }

236− deriving (Eq,Show,GHC.Generic,NFData)

237−instance RenderSQL (FunctionDefinition schemas args ret) where

238− renderSQL = renderFunctionDefinition

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Index.hsdeleted−159

@@ -1,159 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Index

3−Description: Create and drop index definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create and drop index definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Index

33− ( createIndex

34− , createIndexIfNotExists

35− , dropIndex

36− , dropIndexIfExists

37− , IndexMethod (..)

38− , btree

39− , hash

40− , gist

41− , spgist

42− , gin

43− , brin

44− ) where

45−

46−import Data.ByteString

47−import GHC.TypeLits

48−

49−import qualified GHC.Generics as GHC

50−

51−import Squeal.PostgreSQL.Alias

52−import Squeal.PostgreSQL.Definition

53−import Squeal.PostgreSQL.Expression.Sort

54−import Squeal.PostgreSQL.Render

55−import Squeal.PostgreSQL.Schema

56−

57−-- $setup

58−-- >>> import Squeal.PostgreSQL

59−

60−{- |

61−>>> :{

62−type Table = '[] :=>

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

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

65−:}

66−

67−>>> :{

68−let

69− setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table, "ix" ::: 'Index 'Btree])

70− setup =

71− createTable #tab (nullable int `as` #a :* nullable real `as` #b) Nil >>>

72− createIndex #ix #tab btree [#a & AscNullsFirst, #b & AscNullsLast]

73−in printSQL setup

74−:}

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

76−CREATE INDEX "ix" ON "tab" USING btree (("a") ASC NULLS FIRST, ("b") ASC NULLS LAST);

77−-}

78−createIndex

79− :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)

80− => Alias ix

81− -> QualifiedAlias sch tab

82− -> IndexMethod method

83− -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]

84− -> Definition schemas (Alter sch (Create ix ('Index method) schema) schemas)

85−createIndex ix tab method cols = UnsafeDefinition $

86− "CREATE" <+> "INDEX" <+> renderSQL ix <+> "ON" <+> renderSQL tab

87− <+> "USING" <+> renderSQL method

88− <+> parenthesized (commaSeparated (renderIndex <$> cols))

89− <> ";"

90− where

91− renderIndex = \case

92− Asc expression -> parenthesized (renderSQL expression) <+> "ASC"

93− Desc expression -> parenthesized (renderSQL expression) <+> "DESC"

94− AscNullsFirst expression -> parenthesized (renderSQL expression)

95− <+> "ASC NULLS FIRST"

96− DescNullsFirst expression -> parenthesized (renderSQL expression)

97− <+> "DESC NULLS FIRST"

98− AscNullsLast expression -> parenthesized (renderSQL expression)

99− <+> "ASC NULLS LAST"

100− DescNullsLast expression -> parenthesized (renderSQL expression)

101− <+> "DESC NULLS LAST"

102−

103−createIndexIfNotExists

104− :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)

105− => Alias ix

106− -> QualifiedAlias sch tab

107− -> IndexMethod method

108− -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]

109− -> Definition schemas (Alter sch (CreateIfNotExists ix ('Index method) schema) schemas)

110−createIndexIfNotExists ix tab method cols = UnsafeDefinition $

111− "CREATE INDEX IF NOT EXISTS" <+> renderSQL ix <+> "ON" <+> renderSQL tab

112− <+> "USING" <+> renderSQL method

113− <+> parenthesized (commaSeparated (renderIndex <$> cols))

114− <> ";"

115− where

116− renderIndex = \case

117− Asc expression -> parenthesized (renderSQL expression) <+> "ASC"

118− Desc expression -> parenthesized (renderSQL expression) <+> "DESC"

119− AscNullsFirst expression -> parenthesized (renderSQL expression)

120− <+> "ASC NULLS FIRST"

121− DescNullsFirst expression -> parenthesized (renderSQL expression)

122− <+> "DESC NULLS FIRST"

123− AscNullsLast expression -> parenthesized (renderSQL expression)

124− <+> "ASC NULLS LAST"

125− DescNullsLast expression -> parenthesized (renderSQL expression)

126− <+> "DESC NULLS LAST"

127−

128−newtype IndexMethod ty = UnsafeIndexMethod {renderIndexMethod :: ByteString}

129− deriving stock (Eq, Ord, Show, GHC.Generic)

130−instance RenderSQL (IndexMethod ty) where renderSQL = renderIndexMethod

131−btree :: IndexMethod 'Btree

132−btree = UnsafeIndexMethod "btree"

133−hash :: IndexMethod 'Hash

134−hash = UnsafeIndexMethod "hash"

135−gist :: IndexMethod 'Gist

136−gist = UnsafeIndexMethod "gist"

137−spgist :: IndexMethod 'Spgist

138−spgist = UnsafeIndexMethod "spgist"

139−gin :: IndexMethod 'Gin

140−gin = UnsafeIndexMethod "gin"

141−brin :: IndexMethod 'Brin

142−brin = UnsafeIndexMethod "brin"

143−

144−-- |

145−-- >>> printSQL (dropIndex #ix :: Definition (Public '["ix" ::: 'Index 'Btree]) (Public '[]))

146−-- DROP INDEX "ix";

147−dropIndex

148− :: (Has sch schemas schema, KnownSymbol ix)

149− => QualifiedAlias sch ix

150− -- ^ name of the user defined index

151− -> Definition schemas (Alter sch (DropSchemum ix 'Index schema) schemas)

152−dropIndex ix = UnsafeDefinition $ "DROP" <+> "INDEX" <+> renderSQL ix <> ";"

153−

154−dropIndexIfExists

155− :: (Has sch schemas schema, KnownSymbol ix)

156− => QualifiedAlias sch ix

157− -- ^ name of the user defined index

158− -> Definition schemas (Alter sch (DropSchemumIfExists ix 'Index schema) schemas)

159−dropIndexIfExists ix = UnsafeDefinition $ "DROP INDEX IF EXISTS" <+> renderSQL ix <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Schema.hsdeleted−96

@@ -1,96 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Schema

3−Description: Create and drop schema definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create and drop schema definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Schema

33− ( createSchema

34− , createSchemaIfNotExists

35− , dropSchema

36− , dropSchemaIfExists

37− ) where

38−

39−import GHC.TypeLits

40−

41−import Squeal.PostgreSQL.Alias

42−import Squeal.PostgreSQL.Definition

43−import Squeal.PostgreSQL.Render

44−import Squeal.PostgreSQL.Schema

45−

46−-- $setup

47−-- >>> import Squeal.PostgreSQL

48−

49−{- |

50−`createSchema` enters a new schema into the current database.

51−The schema name must be distinct from the name of any existing schema

52−in the current database.

53−

54−A schema is essentially a namespace: it contains named objects

55−(tables, data types, functions, and operators) whose names

56−can duplicate those of other objects existing in other schemas.

57−Named objects are accessed by `QualifiedAlias`es with the schema

58−name as a prefix.

59−-}

60−createSchema

61− :: KnownSymbol sch

62− => Alias sch

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

64−createSchema sch = UnsafeDefinition $

65− "CREATE" <+> "SCHEMA" <+> renderSQL sch <> ";"

66−

67−{- | Idempotent version of `createSchema`. -}

68−createSchemaIfNotExists

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

70− => Alias sch

71− -> Definition schemas (CreateIfNotExists sch '[] schemas)

72−createSchemaIfNotExists sch = UnsafeDefinition $

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

74− <+> renderSQL sch <> ";"

75−

76−-- | >>> :{

77−-- let

78−-- definition :: Definition '["muh_schema" ::: schema, "public" ::: public] '["public" ::: public]

79−-- definition = dropSchema #muh_schema

80−-- :}

81−--

82−-- >>> printSQL definition

83−-- DROP SCHEMA "muh_schema";

84−dropSchema

85− :: KnownSymbol sch

86− => Alias sch

87− -- ^ user defined schema

88− -> Definition schemas (Drop sch schemas)

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

90−

91−dropSchemaIfExists

92− :: KnownSymbol sch

93− => Alias sch

94− -- ^ user defined schema

95− -> Definition schemas (DropIfExists sch schemas)

96−dropSchemaIfExists sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table.hsdeleted−500

@@ -1,500 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Table

3−Description: Create, drop and alter table definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create, drop and alter table definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Table

33− ( createTable

34− , createTableIfNotExists

35− , dropTable

36− , dropTableIfExists

37− , alterTable

38− , alterTableIfExists

39− , alterTableRename

40− , alterTableIfExistsRename

41− , AlterTable (..)

42− , addConstraint

43− , dropConstraint

44− , AddColumn (..)

45− , dropColumn

46− , renameColumn

47− , alterColumn

48− , AlterColumn (..)

49− , setDefault

50− , dropDefault

51− , setNotNull

52− , dropNotNull

53− , alterType

54− ) where

55−

56−import Control.DeepSeq

57−import Data.ByteString

58−import GHC.TypeLits

59−

60−import qualified Generics.SOP as SOP

61−import qualified GHC.Generics as GHC

62−

63−import Squeal.PostgreSQL.Alias

64−import Squeal.PostgreSQL.Definition

65−import Squeal.PostgreSQL.Definition.Table.Constraint

66−import Squeal.PostgreSQL.Expression

67−import Squeal.PostgreSQL.Expression.Type

68−import Squeal.PostgreSQL.List

69−import Squeal.PostgreSQL.Render

70−import Squeal.PostgreSQL.Schema

71−

72−-- $setup

73−-- >>> import Squeal.PostgreSQL

74−

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

76−

77−>>> :set -XOverloadedLabels

78−>>> :{

79−type Table = '[] :=>

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

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

82−:}

83−

84−>>> :{

85−let

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

87− setup = createTable #tab

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

89−in printSQL setup

90−:}

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

92−-}

93−createTable

94− :: ( KnownSymbol sch

95− , KnownSymbol tab

96− , columns ~ (col ': cols)

97− , SOP.SListI columns

98− , SOP.SListI constraints

99− , Has sch schemas0 schema0

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

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

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

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

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

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

106− -> Definition schemas0 schemas1

107−createTable tab columns constraints = UnsafeDefinition $

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

109−

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

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

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

113−the `Category` of `Definition`s.

114−

115−>>> :set -XOverloadedLabels -XTypeApplications

116−>>> :{

117−type Table = '[] :=>

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

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

120−:}

121−

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

123−

124−>>> :{

125−let

126− setup :: Definition Schemas Schemas

127− setup = createTableIfNotExists #tab

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

129−in printSQL setup

130−:}

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

132−-}

133−createTableIfNotExists

134− :: ( KnownSymbol sch

135− , KnownSymbol tab

136− , columns ~ (col ': cols)

137− , SOP.SListI columns

138− , SOP.SListI constraints

139− , Has sch schemas0 schema0

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

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

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

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

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

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

146− -> Definition schemas0 schemas1

147−createTableIfNotExists tab columns constraints = UnsafeDefinition $

148− "CREATE TABLE IF NOT EXISTS"

149− <+> renderCreation tab columns constraints

150−

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

152−renderCreation

153− :: ( KnownSymbol sch

154− , KnownSymbol tab

155− , SOP.SListI columns

156− , SOP.SListI constraints )

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

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

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

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

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

162− -> ByteString

163−renderCreation tab columns constraints = renderSQL tab

164− <+> parenthesized

165− ( renderCommaSeparated renderColumnDef columns

166− <> ( case constraints of

167− Nil -> ""

168− _ -> ", " <>

169− renderCommaSeparated renderConstraint constraints ) )

170− <> ";"

171− where

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

173− renderColumnDef (ty `As` column) =

174− renderSQL column <+> renderColumnTypeExpression ty

175− renderConstraint

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

177− -> ByteString

178− renderConstraint (constraint `As` alias) =

179− "CONSTRAINT" <+> renderSQL alias <+> renderSQL constraint

180−

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

182−--

183−-- >>> :{

184−-- let

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

186−-- definition = dropTable #muh_table

187−-- :}

188−--

189−-- >>> printSQL definition

190−-- DROP TABLE "muh_table";

191−dropTable

192− :: ( Has sch schemas schema

193− , KnownSymbol tab )

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

195− -> Definition schemas (Alter sch (DropSchemum tab 'Table schema) schemas)

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

197−

198−dropTableIfExists

199− :: ( Has sch schemas schema

200− , KnownSymbol tab)

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

202− -> Definition schemas (Alter sch (DropSchemumIfExists tab 'Table schema) schemas)

203−dropTableIfExists tab = UnsafeDefinition $ "DROP TABLE IF EXISTS" <+> renderSQL tab <> ";"

204−

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

206−alterTable

207− :: (Has sch schemas schema, KnownSymbol tab)

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

209− -> AlterTable sch tab schemas table -- ^ alteration to perform

210− -> Definition schemas (Alter sch (Alter tab ('Table table) schema) schemas)

211−alterTable tab alteration = UnsafeDefinition $

212− "ALTER TABLE"

213− <+> renderSQL tab

214− <+> renderAlterTable alteration

215− <> ";"

216−

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

218−alterTableIfExists

219− :: (Has sch schemas schema, KnownSymbol tab)

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

221− -> AlterTable sch tab schemas table -- ^ alteration to perform

222− -> Definition schemas (Alter sch (AlterIfExists tab ('Table table) schema) schemas)

223−alterTableIfExists tab alteration = UnsafeDefinition $

224− "ALTER TABLE IF EXISTS"

225− <+> renderSQL tab

226− <+> renderAlterTable alteration

227− <> ";"

228−

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

230−--

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

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

233−alterTableRename

234− :: (KnownSymbol tab0, KnownSymbol tab1)

235− => Alias tab0 -- ^ table to rename

236− -> Alias tab1 -- ^ what to rename it

237− -> Definition schema (Rename tab0 tab1 schema)

238−alterTableRename tab0 tab1 = UnsafeDefinition $

239− "ALTER TABLE" <+> renderSQL tab0

240− <+> "RENAME TO" <+> renderSQL tab1 <> ";"

241−

242−alterTableIfExistsRename

243− :: (KnownSymbol tab0, KnownSymbol tab1)

244− => Alias tab0 -- ^ table to rename

245− -> Alias tab1 -- ^ what to rename it

246− -> Definition schema (RenameIfExists tab0 tab1 schema)

247−alterTableIfExistsRename tab0 tab1 = UnsafeDefinition $

248− "ALTER TABLE IF EXISTS" <+> renderSQL tab0

249− <+> "RENAME TO" <+> renderSQL tab1 <> ";"

250−

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

252−-- of a table.

253−newtype AlterTable

254− (sch :: Symbol)

255− (tab :: Symbol)

256− (schemas :: SchemasType)

257− (table :: TableType) =

258− UnsafeAlterTable {renderAlterTable :: ByteString}

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

260−

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

262−--

263−-- >>> :{

264−-- let

265−-- definition :: Definition

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

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

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

269−-- in printSQL definition

270−-- :}

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

272−addConstraint

273− :: ( KnownSymbol alias

274− , Has sch schemas schema

275− , Has tab schema ('Table table0)

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

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

278− => Alias alias

279− -> TableConstraintExpression sch tab schemas constraint

280− -- ^ constraint to add

281− -> AlterTable sch tab schemas table1

282−addConstraint alias constraint = UnsafeAlterTable $

283− "ADD" <+> "CONSTRAINT" <+> renderSQL alias

284− <+> renderSQL constraint

285−

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

287−--

288−-- >>> :{

289−-- let

290−-- definition :: Definition

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

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

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

294−-- in printSQL definition

295−-- :}

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

297−dropConstraint

298− :: ( KnownSymbol constraint

299− , Has sch schemas schema

300− , Has tab schema ('Table table0)

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

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

303− => Alias constraint

304− -- ^ constraint to drop

305− -> AlterTable sch tab schemas table1

306−dropConstraint constraint = UnsafeAlterTable $

307− "DROP" <+> "CONSTRAINT" <+> renderSQL constraint

308−

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

310−class AddColumn ty where

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

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

313− --

314− -- >>> :{

315− -- let

316− -- definition :: Definition

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

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

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

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

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

322− -- in printSQL definition

323− -- :}

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

325− --

326− -- >>> :{

327− -- let

328− -- definition :: Definition

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

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

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

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

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

334− -- in printSQL definition

335− -- :}

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

337− addColumn

338− :: ( KnownSymbol column

339− , Has sch schemas schema

340− , Has tab schema ('Table table0)

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

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

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

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

345− addColumn column ty = UnsafeAlterTable $

346− "ADD COLUMN" <+> renderSQL column <+> renderColumnTypeExpression ty

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

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

349−

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

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

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

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

354−--

355−-- >>> :{

356−-- let

357−-- definition :: Definition

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

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

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

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

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

363−-- in printSQL definition

364−-- :}

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

366−dropColumn

367− :: ( KnownSymbol column

368− , Has sch schemas schema

369− , Has tab schema ('Table table0)

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

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

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

373− -> AlterTable sch tab schemas table1

374−dropColumn column = UnsafeAlterTable $

375− "DROP COLUMN" <+> renderSQL column

376−

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

378−--

379−-- >>> :{

380−-- let

381−-- definition :: Definition

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

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

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

385−-- in printSQL definition

386−-- :}

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

388−renameColumn

389− :: ( KnownSymbol column0

390− , KnownSymbol column1

391− , Has sch schemas schema

392− , Has tab schema ('Table table0)

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

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

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

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

397− -> AlterTable sch tab schemas table1

398−renameColumn column0 column1 = UnsafeAlterTable $

399− "RENAME COLUMN" <+> renderSQL column0 <+> "TO" <+> renderSQL column1

400−

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

402−alterColumn

403− :: ( KnownSymbol column

404− , Has sch schemas schema

405− , Has tab schema ('Table table0)

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

407− , Has column columns ty0

408− , table1 ~ (constraints :=> Alter column ty1 columns))

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

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

411− -> AlterTable sch tab schemas table1

412−alterColumn column alteration = UnsafeAlterTable $

413− "ALTER COLUMN" <+> renderSQL column <+> renderAlterColumn alteration

414−

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

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

417− UnsafeAlterColumn {renderAlterColumn :: ByteString}

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

419−

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

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

422−-- future insert and update commands.

423−--

424−-- >>> :{

425−-- let

426−-- definition :: Definition

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

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

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

430−-- in printSQL definition

431−-- :}

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

433−setDefault

434− :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty -- ^ default value to set

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

436−setDefault expression = UnsafeAlterColumn $

437− "SET DEFAULT" <+> renderExpression expression

438−

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

440−--

441−-- >>> :{

442−-- let

443−-- definition :: Definition

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

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

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

447−-- in printSQL definition

448−-- :}

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

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

451−dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"

452−

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

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

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

456−--

457−-- >>> :{

458−-- let

459−-- definition :: Definition

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

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

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

463−-- in printSQL definition

464−-- :}

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

466−setNotNull

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

468−setNotNull = UnsafeAlterColumn $ "SET NOT NULL"

469−

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

471−--

472−-- >>> :{

473−-- let

474−-- definition :: Definition

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

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

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

478−-- in printSQL definition

479−-- :}

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

481−dropNotNull

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

483−dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"

484−

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

486−-- This will succeed only if each existing entry in the column can be

487−-- converted to the new type by an implicit cast.

488−--

489−-- >>> :{

490−-- let

491−-- definition :: Definition

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

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

494−-- definition =

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

496−-- in printSQL definition

497−-- :}

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

499−alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty

500−alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Table/Constraint.hsdeleted−339

@@ -1,339 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Table.Constraint

3−Description: Table constraint expressions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Table constraint expressions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Table.Constraint

33− ( TableConstraintExpression (..)

34− , check

35− , unique

36− , primaryKey

37− , foreignKey

38− , ForeignKeyed

39− , OnDeleteClause (..)

40− , OnUpdateClause (..)

41− ) where

42−

43−import Control.DeepSeq

44−import Data.ByteString

45−import GHC.TypeLits

46−

47−import qualified Generics.SOP as SOP

48−import qualified GHC.Generics as GHC

49−

50−import Squeal.PostgreSQL.Alias

51−import Squeal.PostgreSQL.Expression.Logic

52−import Squeal.PostgreSQL.List

53−import Squeal.PostgreSQL.Render

54−import Squeal.PostgreSQL.Schema

55−

56−-- $setup

57−-- >>> import Squeal.PostgreSQL

58−

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

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

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

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

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

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

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

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

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

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

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

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

71−newtype TableConstraintExpression

72− (sch :: Symbol)

73− (tab :: Symbol)

74− (schemas :: SchemasType)

75− (constraint :: TableConstraint)

76− = UnsafeTableConstraintExpression

77− { renderTableConstraintExpression :: ByteString }

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

79−instance RenderSQL

80− (TableConstraintExpression sch tab schemas constraint) where

81− renderSQL = renderTableConstraintExpression

82−

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

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

85−a Boolean (truth-value) expression.

86−

87−>>> :{

88−type Schema = '[

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

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

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

92− ])]

93−:}

94−

95−>>> :{

96−let

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

98− definition = createTable #tab

99− ( (int & notNullable) `as` #a :*

100− (int & notNullable) `as` #b )

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

102−:}

103−

104−>>> printSQL definition

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

106−-}

107−check

108− :: ( Has sch schemas schema

109− , Has tab schema ('Table table)

110− , HasAll aliases (TableToRow table) subcolumns )

111− => NP Alias aliases

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

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

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

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

116−check _cols condition = UnsafeTableConstraintExpression $

117− "CHECK" <+> parenthesized (renderSQL condition)

118−

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

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

121−

122−>>> :{

123−type Schema = '[

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

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

126− "b" ::: 'NoDef :=> 'Null 'PGint4

127− ])]

128−:}

129−

130−>>> :{

131−let

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

133− definition = createTable #tab

134− ( (int & nullable) `as` #a :*

135− (int & nullable) `as` #b )

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

137−:}

138−

139−>>> printSQL definition

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

141−-}

142−unique

143− :: ( Has sch schemas schema

144− , Has tab schema('Table table)

145− , HasAll aliases (TableToRow table) subcolumns )

146− => NP Alias aliases

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

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

149−unique columns = UnsafeTableConstraintExpression $

150− "UNIQUE" <+> parenthesized (renderSQL columns)

151−

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

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

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

155−

156−>>> :{

157−type Schema = '[

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

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

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

161− ])]

162−:}

163−

164−>>> :{

165−let

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

167− definition = createTable #tab

168− ( serial `as` #id :*

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

170− ( primaryKey #id `as` #pk_id )

171−:}

172−

173−>>> printSQL definition

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

175−-}

176−primaryKey

177− :: ( Has sch schemas schema

178− , Has tab schema ('Table table)

179− , HasAll aliases (TableToColumns table) subcolumns

180− , AllNotNull subcolumns )

181− => NP Alias aliases

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

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

184−primaryKey columns = UnsafeTableConstraintExpression $

185− "PRIMARY KEY" <+> parenthesized (renderSQL columns)

186−

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

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

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

190−between two related tables.

191−

192−>>> :{

193−type Schema =

194− '[ "users" ::: 'Table (

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

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

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

198− ])

199− , "emails" ::: 'Table (

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

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

202− ] :=>

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

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

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

206− ])

207− ]

208−:}

209−

210−>>> :{

211−let

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

213− setup =

214− createTable #users

215− ( serial `as` #id :*

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

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

218− createTable #emails

219− ( serial `as` #id :*

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

221− (text & nullable) `as` #email )

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

223− foreignKey #user_id #users #id

224− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

225−in printSQL setup

226−:}

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

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

229−

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

231−

232−>>> :{

233−type Schema =

234− '[ "employees" ::: 'Table (

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

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

237− ] :=>

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

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

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

241− ])

242− ]

243−:}

244−

245−>>> :{

246−let

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

248− setup =

249− createTable #employees

250− ( serial `as` #id :*

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

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

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

254− foreignKey #employer_id #employees #id

255− OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )

256−in printSQL setup

257−:}

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

259−-}

260−foreignKey

261− :: (ForeignKeyed schemas sch schema child parent

262− table reftable

263− columns refcolumns

264− constraints cols

265− reftys tys )

266− => NP Alias columns

267− -- ^ column or columns in the table

268− -> Alias parent

269− -- ^ reference table

270− -> NP Alias refcolumns

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

272− -> OnDeleteClause

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

274− -> OnUpdateClause

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

276− -> TableConstraintExpression sch child schemas

277− ('ForeignKey columns parent refcolumns)

278−foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $

279− "FOREIGN KEY" <+> parenthesized (renderSQL keys)

280− <+> "REFERENCES" <+> renderSQL parent

281− <+> parenthesized (renderSQL refs)

282− <+> renderSQL ondel

283− <+> renderSQL onupd

284−

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

286−type ForeignKeyed schemas

287− sch

288− schema

289− child parent

290− table reftable

291− columns refcolumns

292− constraints cols

293− reftys tys =

294− ( Has sch schemas schema

295− , Has child schema ('Table table)

296− , Has parent schema ('Table reftable)

297− , HasAll columns (TableToColumns table) tys

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

299− , HasAll refcolumns cols reftys

300− , SOP.AllZip SamePGType tys reftys

301− , Uniquely refcolumns constraints )

302−

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

304−data OnDeleteClause

305− = OnDeleteNoAction

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

307− -- an error is raised

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

309− | OnDeleteCascade

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

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

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

313−instance NFData OnDeleteClause

314−-- | Render `OnDeleteClause`.

315−instance RenderSQL OnDeleteClause where

316− renderSQL = \case

317− OnDeleteNoAction -> "ON DELETE NO ACTION"

318− OnDeleteRestrict -> "ON DELETE RESTRICT"

319− OnDeleteCascade -> "ON DELETE CASCADE"

320−

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

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

323−data OnUpdateClause

324− = OnUpdateNoAction

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

326− -- an error is raised

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

328− | OnUpdateCascade

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

330− -- into the referencing row(s)

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

332−instance NFData OnUpdateClause

333−

334−-- | Render `OnUpdateClause`.

335−instance RenderSQL OnUpdateClause where

336− renderSQL = \case

337− OnUpdateNoAction -> "ON UPDATE NO ACTION"

338− OnUpdateRestrict -> "ON UPDATE RESTRICT"

339− OnUpdateCascade -> "ON UPDATE CASCADE"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/Type.hsdeleted−229

@@ -1,229 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.Type

3−Description: Create and drop type definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create and drop type definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.Type

33− ( createTypeEnum

34− , createTypeEnumFrom

35− , createTypeComposite

36− , createTypeCompositeFrom

37− , createTypeRange

38− , createDomain

39− , dropType

40− , dropTypeIfExists

41− ) where

42−

43−import Data.ByteString

44−import Data.Monoid

45−import GHC.TypeLits

46−import Prelude hiding ((.), id)

47−

48−import qualified Generics.SOP as SOP

49−

50−import Squeal.PostgreSQL.Alias

51−import Squeal.PostgreSQL.Expression.Logic

52−import Squeal.PostgreSQL.Expression.Type

53−import Squeal.PostgreSQL.Definition

54−import Squeal.PostgreSQL.List

55−import Squeal.PostgreSQL.PG

56−import Squeal.PostgreSQL.Render

57−import Squeal.PostgreSQL.Schema

58−

59−-- $setup

60−-- >>> import Squeal.PostgreSQL

61−-- >>> import qualified GHC.Generics as GHC

62−-- >>> import qualified Generics.SOP as SOP

63−

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

65−--

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

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

68−createTypeEnum

69− :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)

70− => QualifiedAlias sch enum

71− -- ^ name of the user defined enumerated type

72− -> NP PGlabel labels

73− -- ^ labels of the enumerated type

74− -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)

75−createTypeEnum enum labels = UnsafeDefinition $

76− "CREATE" <+> "TYPE" <+> renderSQL enum <+> "AS" <+> "ENUM" <+>

77− parenthesized (renderSQL labels) <> ";"

78−

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

80−--

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

82−-- >>> instance SOP.Generic Schwarma

83−-- >>> instance SOP.HasDatatypeInfo Schwarma

84−-- >>> :{

85−-- let

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

87−-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma

88−-- in

89−-- printSQL createSchwarma

90−-- :}

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

92−createTypeEnumFrom

93− :: forall hask sch enum schemas schema.

94− ( SOP.Generic hask

95− , SOP.All KnownSymbol (LabelsPG hask)

96− , KnownSymbol enum

97− , Has sch schemas schema )

98− => QualifiedAlias sch enum

99− -- ^ name of the user defined enumerated type

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

101−createTypeEnumFrom enum = createTypeEnum enum

102− (SOP.hpure label :: NP PGlabel (LabelsPG hask))

103−

104−{- | `createTypeComposite` creates a composite type. The composite type is

105−specified by a list of attribute names and data types.

106−

107−>>> :{

108−type PGcomplex = 'PGcomposite

109− '[ "real" ::: 'NotNull 'PGfloat8

110− , "imaginary" ::: 'NotNull 'PGfloat8 ]

111−:}

112−

113−>>> :{

114−let

115− setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]

116− setup = createTypeComposite #complex

117− (float8 `as` #real :* float8 `as` #imaginary)

118−in printSQL setup

119−:}

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

121−-}

122−createTypeComposite

123− :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)

124− => QualifiedAlias sch ty

125− -- ^ name of the user defined composite type

126− -> NP (Aliased (TypeExpression schemas)) fields

127− -- ^ list of attribute names and data types

128− -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)

129−createTypeComposite ty fields = UnsafeDefinition $

130− "CREATE" <+> "TYPE" <+> renderSQL ty <+> "AS" <+> parenthesized

131− (renderCommaSeparated renderField fields) <> ";"

132− where

133− renderField :: Aliased (TypeExpression schemas) x -> ByteString

134− renderField (typ `As` alias) =

135− renderSQL alias <+> renderSQL typ

136−

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

138−--

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

140−-- >>> instance SOP.Generic Complex

141−-- >>> instance SOP.HasDatatypeInfo Complex

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

143−-- >>> :{

144−-- let

145−-- createComplex :: Definition (Public '[]) (Public Schema)

146−-- createComplex = createTypeCompositeFrom @Complex #complex

147−-- in

148−-- printSQL createComplex

149−-- :}

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

151−createTypeCompositeFrom

152− :: forall hask sch ty schemas schema.

153− ( SOP.All (FieldTyped schemas) (RowPG hask)

154− , KnownSymbol ty

155− , Has sch schemas schema )

156− => QualifiedAlias sch ty

157− -- ^ name of the user defined composite type

158− -> Definition schemas (Alter sch (Create ty ( 'Typedef (PG (Composite hask))) schema) schemas)

159−createTypeCompositeFrom ty = createTypeComposite ty

160− (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype

161− :: NP (Aliased (TypeExpression schemas)) (RowPG hask))

162−

163−{-|

164−`createDomain` creates a new domain. A domain is essentially a data type

165−with constraints (restrictions on the allowed set of values).

166−

167−Domains are useful for abstracting common constraints on fields

168−into a single location for maintenance. For example, several tables might

169−contain email address columns, all requiring the same `check` constraint

170−to verify the address syntax. Define a domain rather than setting up

171−each table's constraint individually.

172−

173−>>> :{

174−let

175− createPositive :: Definition (Public '[]) (Public '["positive" ::: 'Typedef 'PGfloat4])

176− createPositive = createDomain #positive real (#value .> 0 .&& (#value & isNotNull))

177−in printSQL createPositive

178−:}

179−CREATE DOMAIN "positive" AS real CHECK ((("value" > 0) AND "value" IS NOT NULL));

180−-}

181−createDomain

182− :: (Has sch schemas schema, KnownSymbol dom)

183− => QualifiedAlias sch dom

184− -> (forall null. TypeExpression schemas (null ty))

185− -> (forall tab. Condition '[] '[] 'Ungrouped schemas '[] '[tab ::: '["value" ::: 'Null ty]])

186− -> Definition schemas (Alter sch (Create dom ('Typedef ty) schema) schemas)

187−createDomain dom ty condition =

188− UnsafeDefinition $ "CREATE DOMAIN" <+> renderSQL dom

189− <+> "AS" <+> renderTypeExpression ty

190− <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"

191−

192−{- |

193−>>> :{

194−let

195− createSmallIntRange :: Definition (Public '[]) (Public '["int2range" ::: 'Typedef ('PGrange 'PGint2)])

196− createSmallIntRange = createTypeRange #int2range int2

197−in printSQL createSmallIntRange

198−:}

199−CREATE TYPE "int2range" AS RANGE (subtype = int2);

200−-}

201−createTypeRange

202− :: (Has sch schemas schema, KnownSymbol range)

203− => QualifiedAlias sch range

204− -> (forall null. TypeExpression schemas (null ty))

205− -> Definition schemas (Alter sch (Create range ('Typedef ('PGrange ty)) schema) schemas)

206−createTypeRange range ty = UnsafeDefinition $

207− "CREATE" <+> "TYPE" <+> renderSQL range <+> "AS" <+> "RANGE" <+>

208− parenthesized ("subtype" <+> "=" <+> renderTypeExpression ty) <> ";"

209−

210−-- | Drop a type.

211−--

212−-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

213−-- >>> instance SOP.Generic Schwarma

214−-- >>> instance SOP.HasDatatypeInfo Schwarma

215−-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))

216−-- DROP TYPE "schwarma";

217−dropType

218− :: (Has sch schemas schema, KnownSymbol td)

219− => QualifiedAlias sch td

220− -- ^ name of the user defined type

221− -> Definition schemas (Alter sch (DropSchemum td 'Typedef schema) schemas)

222−dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"

223−

224−dropTypeIfExists

225− :: (Has sch schemas schema, KnownSymbol td)

226− => QualifiedAlias sch td

227− -- ^ name of the user defined type

228− -> Definition schemas (Alter sch (DropSchemumIfExists td 'Typedef schema) schemas)

229−dropTypeIfExists tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Definition/View.hsdeleted−104

@@ -1,104 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Definition.View

3−Description: Create and drop view definitions

4−Copyright: (c) Eitan Chatav, 2017

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Create and drop view definitions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DerivingStrategies

17− , FlexibleContexts

18− , FlexibleInstances

19− , GADTs

20− , LambdaCase

21− , MultiParamTypeClasses

22− , OverloadedLabels

23− , OverloadedStrings

24− , RankNTypes

25− , ScopedTypeVariables

26− , TypeApplications

27− , TypeInType

28− , TypeOperators

29− , UndecidableSuperClasses

30−#-}

31−

32−module Squeal.PostgreSQL.Definition.View

33− ( createView

34− , createOrReplaceView

35− , dropView

36− , dropViewIfExists

37− ) where

38−

39−import GHC.TypeLits

40−

41−import Squeal.PostgreSQL.Alias

42−import Squeal.PostgreSQL.Definition

43−import Squeal.PostgreSQL.Query

44−import Squeal.PostgreSQL.Render

45−import Squeal.PostgreSQL.Schema

46−

47−-- $setup

48−-- >>> import Squeal.PostgreSQL

49−

50−{- | Create a view.

51−>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]

52−>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]

53−>>> :{

54−let

55− definition :: Definition

56− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]

57− '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc" ::: 'View BC]]

58− definition =

59− createView #bc (select_ (#b :* #c) (from (table #abc)))

60−in printSQL definition

61−:}

62−CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";

63−-}

64−createView

65− :: (Has sch schemas schema, KnownSymbol vw)

66− => QualifiedAlias sch vw -- ^ the name of the view to add

67− -> Query '[] '[] schemas '[] view -- ^ query

68− -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)

69−createView alias query = UnsafeDefinition $

70− "CREATE" <+> "VIEW" <+> renderSQL alias <+> "AS"

71− <+> renderQuery query <> ";"

72−

73−createOrReplaceView

74− :: (Has sch schemas schema, KnownSymbol vw)

75− => QualifiedAlias sch vw -- ^ the name of the view to add

76− -> Query '[] '[] schemas '[] view -- ^ query

77− -> Definition schemas (Alter sch (CreateOrReplace vw ('View view) schema) schemas)

78−createOrReplaceView alias query = UnsafeDefinition $

79− "CREATE OR REPLACE VIEW" <+> renderSQL alias <+> "AS"

80− <+> renderQuery query <> ";"

81−

82−-- | Drop a view.

83−--

84−-- >>> :{

85−-- let

86−-- definition :: Definition

87−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])

88−-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]

89−-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]

90−-- definition = dropView #bc

91−-- in printSQL definition

92−-- :}

93−-- DROP VIEW "bc";

94−dropView

95− :: (Has sch schemas schema, KnownSymbol vw)

96− => QualifiedAlias sch vw -- ^ view to remove

97− -> Definition schemas (Alter sch (DropSchemum vw 'View schema) schemas)

98−dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderSQL vw <> ";"

99−

100−dropViewIfExists

101− :: (Has sch schemas schema, KnownSymbol vw)

102− => QualifiedAlias sch vw -- ^ view to remove

103− -> Definition schemas (Alter sch (DropIfExists vw schema) schemas)

104−dropViewIfExists vw = UnsafeDefinition $ "DROP VIEW IF EXISTS" <+> renderSQL vw <> ";"

squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+1083−357

@@ -1,382 +1,407 @@

1{-|

2−Module: Squeal.PostgreSQL.Expression

2+Module: Squeal.PostgreSQL.Query

3Description: Squeal expressions

4−Copyright: (c) Eitan Chatav, 2019

4+Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

8Squeal expressions are the atoms used to build statements.

9-}

11+{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}

11{-# LANGUAGE

12{-# LANGUAGE

12 AllowAmbiguousTypes

13 AllowAmbiguousTypes

13− , ConstraintKinds

14 , DeriveGeneric

15 , FlexibleContexts

16 , FlexibleInstances

17 , FunctionalDependencies

18− , GADTs

19 , GeneralizedNewtypeDeriving

18 , GeneralizedNewtypeDeriving

20 , LambdaCase

19 , LambdaCase

21 , MagicHash

20 , MagicHash

22 , OverloadedStrings

21 , OverloadedStrings

23 , ScopedTypeVariables

22 , ScopedTypeVariables

24− , StandaloneDeriving

25 , TypeApplications

23 , TypeApplications

26 , TypeFamilies

24 , TypeFamilies

27 , TypeInType

25 , TypeInType

28 , TypeOperators

26 , TypeOperators

29 , UndecidableInstances

27 , UndecidableInstances

30− , RankNTypes

31#-}

28#-}

33−module Squeal.PostgreSQL.Expression

30+module Squeal.PostgreSQL.Expression

34 ( -- * Expression

31 ( -- * Expression

35− Expression (..)

32+ Expression (UnsafeExpression, renderExpression)

36− , Expr

33+ , HasParameter (param)

37− , type (-->)

34+ -- ** Null

38− , FunctionDB

35+ , HasNull (null_)

39− , unsafeFunction

36+ , HasNotNull (notNull)

40− , function

37+ , coalesce

41− , unsafeLeftOp

38+ , fromNull

42− , leftOp

39+ , isNull

43− , unsafeRightOp

40+ , isn'tNull

44− , rightOp

41+ , matchNull

45− , Operator

42+ , nullIf

46− , OperatorDB

43+ -- ** Arrays, Enums, Composites

44+ , array

45+ , row

46+ -- ** Functions

47 , unsafeBinaryOp

48− , binaryOp

48+ , unsafeUnaryOp

49− , FunctionVar

49+ , unsafeFunction

50− , unsafeFunctionVar

50+ , atan2_

51− , type (--->)

51+ , cast

52− , FunctionNDB

52+ , quot_

53− , unsafeFunctionN

53+ , rem_

54− , functionN

54+ , trunc

55− , PGSubset (..)

55+ , round_

56− , PGIntersect (..)

56+ , ceiling_

57+ , greatest

58+ , least

59+ -- ** Conditions

60+ , Condition

61+ , true

62+ , false

63+ , not_

64+ , (.&&)

65+ , (.||)

66+ , caseWhenThenElse

67+ , ifThenElse

68+ , (.==)

69+ , (./=)

70+ , (.>=)

71+ , (.<)

72+ , (.<=)

73+ , (.>)

74+ -- ** Time

75+ , currentDate

76+ , currentTime

77+ , currentTimestamp

78+ , localTime

79+ , localTimestamp

80+ -- ** Text

81+ , lower

82+ , upper

83+ , charLength

84+ , like

85+ -- ** Aggregation

86+ , unsafeAggregate, unsafeAggregateDistinct

87+ , sum_, sumDistinct

88+ , PGAvg (avg, avgDistinct)

89+ , bitAnd, bitOr, boolAnd, boolOr

90+ , bitAndDistinct, bitOrDistinct, boolAndDistinct, boolOrDistinct

91+ , countStar

92+ , count, countDistinct

93+ , every, everyDistinct

94+ , max_, maxDistinct, min_, minDistinct

95+ -- * Tables

96+ , Table (UnsafeTable, renderTable)

97+ , View (UnsafeView, renderView)

98+ -- * Types

99+ , TypeExpression (UnsafeTypeExpression, renderTypeExpression)

100+ , PGTyped (pgtype)

101+ , bool

102+ , int2

103+ , smallint

104+ , int4

105+ , int

106+ , integer

107+ , int8

108+ , bigint

109+ , numeric

110+ , float4

111+ , real

112+ , float8

113+ , doublePrecision

114+ , text

115+ , char

116+ , character

117+ , varchar

118+ , characterVarying

119+ , bytea

120+ , timestamp

121+ , timestampWithTimeZone

122+ , date

123+ , time

124+ , timeWithTimeZone

125+ , interval

126+ , uuid

127+ , inet

128+ , json

129+ , jsonb

130+ , vararray

131+ , fixarray

57 -- * Re-export

132 -- * Re-export

58 , (&)

133 , (&)

59− , K (..)

134+ , NP ((:*), Nil)

60− , unK

61 ) where

135 ) where

136

63import Control.Category

137import Control.Category

64import Control.DeepSeq

138import Control.DeepSeq

65import Data.ByteString (ByteString)

139import Data.ByteString (ByteString)

66import Data.Function ((&))

140import Data.Function ((&))

67−import Data.Semigroup hiding (All)

141+import Data.Semigroup

142+import Data.Ratio

68import Data.String

143import Data.String

69−import Generics.SOP hiding (All, from)

144+import Generics.SOP hiding (from)

70import GHC.OverloadedLabels

145import GHC.OverloadedLabels

71import GHC.TypeLits

146import GHC.TypeLits

72−import Numeric

73import Prelude hiding (id, (.))

147import Prelude hiding (id, (.))

148

75import qualified GHC.Generics as GHC

149import qualified GHC.Generics as GHC

150

77−import Squeal.PostgreSQL.Alias

78−import Squeal.PostgreSQL.List

79import Squeal.PostgreSQL.Render

151import Squeal.PostgreSQL.Render

80import Squeal.PostgreSQL.Schema

152import Squeal.PostgreSQL.Schema

153

82−-- $setup

83−-- >>> import Squeal.PostgreSQL

84−

85{-----------------------------------------

154{-----------------------------------------

86column expressions

155column expressions

87-----------------------------------------}

156-----------------------------------------}

157

89{- | `Expression`s are used in a variety of contexts,

158{- | `Expression`s are used in a variety of contexts,

90−such as in the target `Squeal.PostgreSQL.Query.List` of the

91−`Squeal.PostgreSQL.Query.select` command,

159+such as in the target list of the `Squeal.PostgreSQL.Query.select` command,

92as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or

160as new column values in `Squeal.PostgreSQL.Manipulation.insertRow` or

93`Squeal.PostgreSQL.Manipulation.update`,

161`Squeal.PostgreSQL.Manipulation.update`,

94−or in search `Squeal.PostgreSQL.Logic.Condition`s in a number of commands.

162+or in search `Condition`s in a number of commands.

163

96The expression syntax allows the calculation of

164The expression syntax allows the calculation of

97values from primitive expression using arithmetic, logical,

165values from primitive expression using arithmetic, logical,

98and other operations.

166and other operations.

99−

100−The type parameters of `Expression` are

101−

102−* @outer :: @ `FromType`, the @from@ clauses of any outer queries in which

103− the `Expression` is a correlated subquery expression;

104−* @commons :: @ `FromType`, the `Squeal.PostgreSQL.Query.CommonTableExpression`s

105− that are in scope for the `Expression`;

106−* @grp :: @ `Grouping`, the `Grouping` of the @from@ clause which may limit

107− which columns may be referenced by alias;

108−* @schemas :: @ `SchemasType`, the schemas of your database that are in

109− scope for the `Expression`;

110−* @from :: @ `FromType`, the @from@ clause which the `Expression` may use

111− to reference columns by alias;

112−* @ty :: @ `NullityType`, the type of the `Expression`.

113-}

167-}

114newtype Expression

168newtype Expression

115− (outer :: FromType)

169+ (relations :: RelationsType)

116− (commons :: FromType)

117− (grp :: Grouping)

170+ (grouping :: Grouping)

118− (schemas :: SchemasType)

119 (params :: [NullityType])

171 (params :: [NullityType])

120− (from :: FromType)

121 (ty :: NullityType)

172 (ty :: NullityType)

122 = UnsafeExpression { renderExpression :: ByteString }

173 = UnsafeExpression { renderExpression :: ByteString }

123 deriving (GHC.Generic,Show,Eq,Ord,NFData)

174 deriving (GHC.Generic,Show,Eq,Ord,NFData)

124−instance RenderSQL (Expression outer commons grp schemas params from ty) where

175+

125− renderSQL = renderExpression

176+{- | A `HasParameter` constraint is used to indicate a value that is

126−

177+supplied externally to a SQL statement.

127−-- | An `Expr` is a closed `Expression`.

178+`Squeal.PostgreSQL.PQ.manipulateParams`,

128−-- It is a F@RankNType@ but don't be scared.

179+`Squeal.PostgreSQL.PQ.queryParams` and

129−-- Think of it as an expression which sees no

180+`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values

130−-- namespaces, so you can't use parameters

181+separately from the SQL command string, in which case `param`s are used to

131−-- or alias references. It can be used as

182+refer to the out-of-line data values.

132−-- a simple piece of more complex `Expression`s.

133−type Expr x

134− = forall outer commons grp schemas params from

135− . Expression outer commons grp schemas params from x

136− -- ^ cannot reference aliases

137−

138−-- | A @RankNType@ for binary operators.

139−type Operator x1 x2 y

140− = forall outer commons grp schemas params from

141− . Expression outer commons grp schemas params from x1

142− -- ^ left input

143− -> Expression outer commons grp schemas params from x2

144− -- ^ right input

145− -> Expression outer commons grp schemas params from y

146− -- ^ output

147−

148−type OperatorDB schemas x1 x2 y

149− = forall outer commons grp params from

150− . Expression outer commons grp schemas params from x1

151− -- ^ left input

152− -> Expression outer commons grp schemas params from x2

153− -- ^ right input

154− -> Expression outer commons grp schemas params from y

155− -- ^ output

156−

157−-- | A @RankNType@ for functions with a single argument.

158−-- These could be either function calls or unary operators.

159−-- This is a subtype of the usual Haskell function type `Prelude.->`,

160−-- indeed a subcategory as it is closed under the usual

161−-- `Prelude..` and `Prelude.id`.

162−type (-->) x y

163− = forall outer commons grp schemas params from

164− . Expression outer commons grp schemas params from x

165− -- ^ input

166− -> Expression outer commons grp schemas params from y

167− -- ^ output

168−

169−type FunctionDB schemas x y

170− = forall outer commons grp params from

171− . Expression outer commons grp schemas params from x

172− -- ^ input

173− -> Expression outer commons grp schemas params from y

174− -- ^ output

175−

176−{- | A @RankNType@ for functions with a fixed-length list of heterogeneous arguments.

177−Use the `*:` operator to end your argument lists, like so.

178−

179−>>> printSQL (unsafeFunctionN "fun" (true :* false :* localTime *: true))

180−fun(TRUE, FALSE, LOCALTIME, TRUE)

181−-}

182−type (--->) xs y

183− = forall outer commons grp schemas params from

184− . NP (Expression outer commons grp schemas params from) xs

185− -- ^ inputs

186− -> Expression outer commons grp schemas params from y

187− -- ^ output

188−

189−type FunctionNDB schemas xs y

190− = forall outer commons grp params from

191− . NP (Expression outer commons grp schemas params from) xs

192− -- ^ inputs

193− -> Expression outer commons grp schemas params from y

194− -- ^ output

195−

196−{- | A @RankNType@ for functions with a variable-length list of

197−homogeneous arguments and at least 1 more argument.

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-}

183-}

211−unsafeFunctionVar :: ByteString -> FunctionVar x0 x1 y

184+class (PGTyped (PGTypeOf ty), KnownNat n) => HasParameter

185+ (n :: Nat)

186+ (params :: [NullityType])

187+ (ty :: NullityType)

188+ | n params -> ty where

189+ param :: Expression relations grouping params ty

212−unsafeFunctionVar fun xs x = UnsafeExpression $ fun <> parenthesized

190+ param = UnsafeExpression $ parenthesized $

213− (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)

191+ "$" <> renderNat (Proxy @n) <+> "::"

214−

192+ <+> renderTypeExpression (pgtype @(PGTypeOf ty))

215−instance (HasUnique tab (Join outer from) row, Has col row ty)

193+instance {-# OVERLAPPING #-} PGTyped (PGTypeOf ty1)

216− => IsLabel col (Expression outer commons 'Ungrouped schemas params from ty) where

194+ => HasParameter 1 (ty1:tys) ty1

217− fromLabel = UnsafeExpression $ renderSQL (Alias @col)

195+instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)

218−instance (HasUnique tab (Join outer from) row, Has col row ty, tys ~ '[ty])

196+ => HasParameter n (ty' : params) 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

245

197

246−instance

198+instance (HasUnique relation relations columns, Has column columns ty)

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

199+ => IsLabel column (Expression relations 'Ungrouped params ty) where

252− fromLabel = UnsafeExpression $ renderSQL (Alias @col)

200+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)

253−instance

254− ( HasUnique tab (Join outer from) row

255− , Has col row ty

256− , GroupedBy tab col bys

257− , tys ~ '[ty]

258− ) => IsLabel col

259− (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

260− fromLabel = fromLabel @col :* Nil

261−instance

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

277

201

202+instance (Has relation relations columns, Has column columns ty)

203+ => IsQualified relation column (Expression relations 'Ungrouped params ty) where

204+ relation ! column = UnsafeExpression $

205+ renderAlias relation <> "." <> renderAlias column

206+

278instance

207instance

279− ( Has tab (Join outer from) row

208+ ( HasUnique relation relations columns

280− , Has col row ty

209+ , Has column columns ty

281− , GroupedBy tab col bys

210+ , GroupedBy relation column bys

282− ) => IsQualified tab col

211+ ) => IsLabel column

283− (Expression outer commons ('Grouped bys) schemas params from ty) where

212+ (Expression relations ('Grouped bys) params ty) where

284− tab ! col = UnsafeExpression $

213+ fromLabel = UnsafeExpression $ renderAlias (Alias @column)

285− renderSQL tab <> "." <> renderSQL col

214+

286−instance

287− ( Has tab (Join outer from) row

288− , Has col row ty

289− , GroupedBy tab col bys

290− , tys ~ '[ty]

291− ) => IsQualified tab col

292− (NP (Expression outer commons ('Grouped bys) schemas params from) tys) where

293− tab ! col = tab ! col :* Nil

294instance

215instance

295− ( Has tab (Join outer from) row

216+ ( Has relation relations columns

296− , Has col row ty

217+ , Has column columns ty

297− , GroupedBy tab col bys

218+ , GroupedBy relation column bys

298− , column ~ (col ::: ty)

299− ) => IsQualified tab col

219+ ) => IsQualified relation column

300− (Aliased (Expression outer commons ('Grouped bys) schemas params from) column) where

220+ (Expression relations ('Grouped bys) params ty) where

301− tab ! col = tab ! col `As` col

221+ relation ! column = UnsafeExpression $

302−instance

222+ renderAlias relation <> "." <> renderAlias column

303− ( Has tab (Join outer from) row

223+

304− , Has col row ty

224+class HasNull expr where null_ :: expr

305− , GroupedBy tab col bys

225+instance HasNull (Expression rels grouping params ('Null ty)) where

306− , columns ~ '[col ::: ty]

226+ -- | analagous to `Nothing`

307− ) => IsQualified tab col

227+ --

308− (NP (Aliased (Expression outer commons ('Grouped bys) schemas params from)) columns) where

228+ -- >>> renderExpression $ null_

309− tab ! col = tab ! col :* Nil

229+ -- "NULL"

230+ null_ = UnsafeExpression "NULL"

231+

232+class HasNotNull expr where notNull :: expr

233+instance HasNotNull

234+ ( Expression rels grouping params ('NotNull ty)

235+ ->

236+ Expression rels grouping params ('Null ty) ) where

237+ -- | analagous to `Just`

238+ --

239+ -- >>> renderExpression $ notNull true

240+ -- "TRUE"

241+ notNull = UnsafeExpression . renderExpression

242+

243+-- | return the leftmost value which is not NULL

244+--

245+-- >>> renderExpression $ coalesce [null_, notNull true] false

246+-- "COALESCE(NULL, TRUE, FALSE)"

247+coalesce

248+ :: [Expression relations grouping params ('Null ty)]

249+ -- ^ @NULL@s may be present

250+ -> Expression relations grouping params ('NotNull ty)

251+ -- ^ @NULL@ is absent

252+ -> Expression relations grouping params ('NotNull ty)

253+coalesce nullxs notNullx = UnsafeExpression $

254+ "COALESCE" <> parenthesized (commaSeparated

255+ ((renderExpression <$> nullxs) <> [renderExpression notNullx]))

256+

257+-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@

258+--

259+-- >>> renderExpression $ fromNull true null_

260+-- "COALESCE(NULL, TRUE)"

261+fromNull

262+ :: Expression relations grouping params ('NotNull ty)

263+ -- ^ what to convert @NULL@ to

264+ -> Expression relations grouping params ('Null ty)

265+ -> Expression relations grouping params ('NotNull ty)

266+fromNull notNullx nullx = coalesce [nullx] notNullx

267+

268+-- | >>> renderExpression $ null_ & isNull

269+-- "NULL IS NULL"

270+isNull

271+ :: Expression relations grouping params ('Null ty)

272+ -- ^ possibly @NULL@

273+ -> Condition relations grouping params

274+isNull x = UnsafeExpression $ renderExpression x <+> "IS NULL"

275+

276+-- | >>> renderExpression $ null_ & isn'tNull

277+-- "NULL IS NOT NULL"

278+isn'tNull

279+ :: Expression relations grouping params ('Null ty)

280+ -- ^ possibly @NULL@

281+ -> Condition relations grouping params

282+isn'tNull x = UnsafeExpression $ renderExpression x <+> "IS NOT NULL"

283+

284+-- | analagous to `maybe` using @IS NULL@

285+--

286+-- >>> renderExpression $ matchNull true not_ null_

287+-- "CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END"

288+matchNull

289+ :: Expression relations grouping params (nullty)

290+ -- ^ what to convert @NULL@ to

291+ -> ( Expression relations grouping params ('NotNull ty)

292+ -> Expression relations grouping params (nullty) )

293+ -- ^ function to perform when @NULL@ is absent

294+ -> Expression relations grouping params ('Null ty)

295+ -> Expression relations grouping params (nullty)

296+matchNull y f x = ifThenElse (isNull x) y

297+ (f (UnsafeExpression (renderExpression x)))

298+

299+-- | right inverse to `fromNull`, if its arguments are equal then

300+-- `nullIf` gives @NULL@.

301+--

302+-- >>> :set -XTypeApplications -XDataKinds

303+-- >>> renderExpression @_ @_ @'[_] $ fromNull false (nullIf false (param @1))

304+-- "COALESCE(NULL IF (FALSE, ($1 :: bool)), FALSE)"

305+nullIf

306+ :: Expression relations grouping params ('NotNull ty)

307+ -- ^ @NULL@ is absent

308+ -> Expression relations grouping params ('NotNull ty)

309+ -- ^ @NULL@ is absent

310+ -> Expression relations grouping params ('Null ty)

311+nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized

312+ (renderExpression x <> ", " <> renderExpression y)

313+

314+-- | >>> renderExpression $ array [null_, notNull false, notNull true]

315+-- "ARRAY[NULL, FALSE, TRUE]"

316+array

317+ :: [Expression relations grouping params ('Null ty)]

318+ -- ^ array elements

319+ -> Expression relations grouping params (nullity ('PGvararray ty))

320+array xs = UnsafeExpression $

321+ "ARRAY[" <> commaSeparated (renderExpression <$> xs) <> "]"

310

322

311instance (KnownSymbol label, label `In` labels) => IsPGlabel label

323instance (KnownSymbol label, label `In` labels) => IsPGlabel label

312− (Expression outer commons grp schemas params from (null ('PGenum labels))) where

324+ (Expression relations grouping params (nullity ('PGenum labels))) where

313− label = UnsafeExpression $ renderSQL (PGlabel @label)

325+ label = UnsafeExpression $ renderLabel (PGlabel @label)

314

326

327+row

328+ :: (SListI (Nulls fields))

329+ => NP (Aliased (Expression relation grouping params)) (Nulls fields)

330+ -> Expression relation grouping params (nullity ('PGcomposite fields))

331+row exprs = UnsafeExpression $ "ROW" <> parenthesized

332+ (renderCommaSeparated (\ (expr `As` _) -> renderExpression expr) exprs)

333+

334+instance Has field fields ty => IsLabel field

335+ ( Expression relation grouping params (nullity ('PGcomposite fields))

336+ -> Expression relation grouping params ('Null ty) ) where

337+ fromLabel expr = UnsafeExpression $

338+ parenthesized (renderExpression expr) <> "." <>

339+ fromString (symbolVal (Proxy @field))

340+

341+instance Semigroup

342+ (Expression relations grouping params (nullity ('PGvararray ty))) where

343+ (<>) = unsafeBinaryOp "||"

344+

345+instance Monoid

346+ (Expression relations grouping params (nullity ('PGvararray ty))) where

347+ mempty = array []

348+ mappend = (<>)

349+

350+-- | >>> renderExpression @_ @_ @'[_] $ greatest currentTimestamp [param @1]

351+-- "GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))"

352+greatest

353+ :: Expression relations grouping params (nullty)

354+ -- ^ needs at least 1 argument

355+ -> [Expression relations grouping params (nullty)]

356+ -- ^ or more

357+ -> Expression relations grouping params (nullty)

358+greatest x xs = UnsafeExpression $ "GREATEST("

359+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

360+

361+-- | >>> renderExpression $ least currentTimestamp [null_]

362+-- "LEAST(CURRENT_TIMESTAMP, NULL)"

363+least

364+ :: Expression relations grouping params (nullty)

365+ -- ^ needs at least 1 argument

366+ -> [Expression relations grouping params (nullty)]

367+ -- ^ or more

368+ -> Expression relations grouping params (nullty)

369+least x xs = UnsafeExpression $ "LEAST("

370+ <> commaSeparated (renderExpression <$> (x:xs)) <> ")"

371+

315−-- | >>> printSQL $ unsafeBinaryOp "OR" true false

372+-- | >>> renderExpression $ unsafeBinaryOp "OR" true false

316−-- (TRUE OR FALSE)

373+-- "(TRUE OR FALSE)"

317−unsafeBinaryOp :: ByteString -> Operator ty0 ty1 ty2

374+unsafeBinaryOp

375+ :: ByteString

376+ -- ^ operator

377+ -> Expression relations grouping params (ty0)

378+ -> Expression relations grouping params (ty1)

379+ -> Expression relations grouping params (ty2)

318unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $

380unsafeBinaryOp op x y = UnsafeExpression $ parenthesized $

319− renderSQL x <+> op <+> renderSQL y

381+ renderExpression x <+> op <+> renderExpression y

320−

382+

321−binaryOp

383+-- | >>> renderExpression $ unsafeUnaryOp "NOT" true

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

329−-- (NOT TRUE)

384+-- "(NOT TRUE)"

330−unsafeLeftOp :: ByteString -> x --> y

385+unsafeUnaryOp

331−unsafeLeftOp op x = UnsafeExpression $ parenthesized $ op <+> renderSQL x

386+ :: ByteString

332−

387+ -- ^ operator

333−leftOp

388+ -> Expression relations grouping params (ty0)

334− :: forall op sch schemas schema x y.

389+ -> Expression relations grouping params (ty1)

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

390+unsafeUnaryOp op x = UnsafeExpression $ parenthesized $

344−

391+ op <+> renderExpression x

345−rightOp

392+

346− :: forall op sch schemas schema x y.

347− ( Has sch schemas schema

348− , Has op schema ('Operator ('RightOp x y)) )

349− => FunctionDB schemas x y

350−rightOp = unsafeRightOp $ renderSymbol @op

351−

352−-- | >>> printSQL $ unsafeFunction "f" true

393+-- | >>> renderExpression $ unsafeFunction "f" true

353−-- f(TRUE)

394+-- "f(TRUE)"

354−unsafeFunction :: ByteString -> x --> y

395+unsafeFunction

396+ :: ByteString

397+ -- ^ function

398+ -> Expression relations grouping params (xty)

399+ -> Expression relations grouping params (yty)

355unsafeFunction fun x = UnsafeExpression $

400unsafeFunction fun x = UnsafeExpression $

356− fun <> parenthesized (renderSQL x)

401+ fun <> parenthesized (renderExpression x)

357−

402+

358−function

359− :: (Has sch schemas schema, Has fun schema ('Function ('[x] :=> 'Returns y)))

360− => QualifiedAlias sch fun

361− -> FunctionDB schemas x y

362−function = unsafeFunction . renderSQL

363−

364−-- | >>> printSQL $ unsafeFunctionN "f" (currentTime :* localTimestamp :* false *: literal 'a')

365−-- f(CURRENT_TIME, LOCALTIMESTAMP, FALSE, E'a')

366−unsafeFunctionN :: SListI xs => ByteString -> xs ---> y

367−unsafeFunctionN fun xs = UnsafeExpression $

368− fun <> parenthesized (renderCommaSeparated renderSQL xs)

369−

370−functionN

371− :: ( Has sch schemas schema

372− , Has fun schema ('Function (xs :=> 'Returns y))

373− , SListI xs )

374− => QualifiedAlias sch fun

375− -> FunctionNDB schemas xs y

376−functionN = unsafeFunctionN . renderSQL

377−

378−instance ty `In` PGNum

403+instance PGNum ty

379− => Num (Expression outer commons grp schemas params from (null ty)) where

404+ => Num (Expression relations grouping params (nullity ty)) where

380 (+) = unsafeBinaryOp "+"

405 (+) = unsafeBinaryOp "+"

381 (-) = unsafeBinaryOp "-"

406 (-) = unsafeBinaryOp "-"

382 (*) = unsafeBinaryOp "*"

407 (*) = unsafeBinaryOp "*"

@@ -387,24 +412,19 @@ instance ty `In` PGNum

387 . fromString

412 . fromString

388 . show

413 . show

389

414

390−instance (ty `In` PGNum, ty `In` PGFloating) => Fractional

415+instance (PGNum ty, PGFloating ty) => Fractional

391− (Expression outer commons grp schemas params from (null ty)) where

416+ (Expression relations grouping params (nullity ty)) where

392 (/) = unsafeBinaryOp "/"

417 (/) = unsafeBinaryOp "/"

393− fromRational

418+ fromRational x = fromInteger (numerator x) / fromInteger (denominator x)

394− = UnsafeExpression

395− . fromString

396− . ($ "")

397− . showFFloat Nothing

398− . fromRat @Double

399

419

400−instance (ty `In` PGNum, ty `In` PGFloating) => Floating

420+instance (PGNum ty, PGFloating ty) => Floating

401− (Expression outer commons grp schemas params from (null ty)) where

421+ (Expression relations grouping params (nullity ty)) where

402 pi = UnsafeExpression "pi()"

422 pi = UnsafeExpression "pi()"

403 exp = unsafeFunction "exp"

423 exp = unsafeFunction "exp"

404 log = unsafeFunction "ln"

424 log = unsafeFunction "ln"

405 sqrt = unsafeFunction "sqrt"

425 sqrt = unsafeFunction "sqrt"

406 b ** x = UnsafeExpression $

426 b ** x = UnsafeExpression $

407− "power(" <> renderSQL b <> ", " <> renderSQL x <> ")"

427+ "power(" <> renderExpression b <> ", " <> renderExpression x <> ")"

408 logBase b y = log y / log b

428 logBase b y = log y / log b

409 sin = unsafeFunction "sin"

429 sin = unsafeFunction "sin"

410 cos = unsafeFunction "cos"

430 cos = unsafeFunction "cos"

@@ -419,54 +439,760 @@ instance (ty `In` PGNum, ty `In` PGFloating) => Floating

419 acosh x = log (x + sqrt (x*x - 1))

439 acosh x = log (x + sqrt (x*x - 1))

420 atanh x = log ((1 + x) / (1 - x)) / 2

440 atanh x = log ((1 + x) / (1 - x)) / 2

421

441

422−-- | Contained by operators

442+-- | >>> :{

423−class PGSubset ty where

443+-- let

424− (@>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

444+-- expression :: Expression relations grouping params (nullity 'PGfloat4)

425− (@>) = unsafeBinaryOp "@>"

445+-- expression = atan2_ pi 2

426− (<@) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

446+-- in renderExpression expression

427− (<@) = unsafeBinaryOp "<@"

447+-- :}

428−instance PGSubset 'PGjsonb

448+-- "atan2(pi(), 2)"

429−instance PGSubset 'PGtsquery

449+atan2_

430−instance PGSubset ('PGvararray ty)

450+ :: PGFloating float

431−instance PGSubset ('PGrange ty)

451+ => Expression relations grouping params (nullity float)

432−

452+ -- ^ numerator

433−class PGIntersect ty where

453+ -> Expression relations grouping params (nullity float)

434− (@&&) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

454+ -- ^ denominator

435− (@&&) = unsafeBinaryOp "&&"

455+ -> Expression relations grouping params (nullity float)

436−instance PGIntersect ('PGvararray ty)

456+atan2_ y x = UnsafeExpression $

437−instance PGIntersect ('PGrange ty)

457+ "atan2(" <> renderExpression y <> ", " <> renderExpression x <> ")"

458+

459+-- When a `cast` is applied to an `Expression` of a known type, it

460+-- represents a run-time type conversion. The cast will succeed only if a

461+-- suitable type conversion operation has been defined.

462+--

463+-- | >>> renderExpression $ true & cast int4

464+-- "(TRUE :: int4)"

465+cast

466+ :: TypeExpression ty1

467+ -- ^ type to cast as

468+ -> Expression relations grouping params (nullity ty0)

469+ -- ^ value to convert

470+ -> Expression relations grouping params (nullity ty1)

471+cast ty x = UnsafeExpression $ parenthesized $

472+ renderExpression x <+> "::" <+> renderTypeExpression ty

473+

474+-- | integer division, truncates the result

475+--

476+-- >>> :{

477+-- let

478+-- expression :: Expression relations grouping params (nullity 'PGint2)

479+-- expression = 5 `quot_` 2

480+-- in renderExpression expression

481+-- :}

482+-- "(5 / 2)"

483+quot_

484+ :: PGIntegral int

485+ => Expression relations grouping params (nullity int)

486+ -- ^ numerator

487+ -> Expression relations grouping params (nullity int)

488+ -- ^ denominator

489+ -> Expression relations grouping params (nullity int)

490+quot_ = unsafeBinaryOp "/"

491+

492+-- | remainder upon integer division

493+--

494+-- >>> :{

495+-- let

496+-- expression :: Expression relations grouping params (nullity 'PGint2)

497+-- expression = 5 `rem_` 2

498+-- in renderExpression expression

499+-- :}

500+-- "(5 % 2)"

501+rem_

502+ :: PGIntegral int

503+ => Expression relations grouping params (nullity int)

504+ -- ^ numerator

505+ -> Expression relations grouping params (nullity int)

506+ -- ^ denominator

507+ -> Expression relations grouping params (nullity int)

508+rem_ = unsafeBinaryOp "%"

509+

510+-- | >>> :{

511+-- let

512+-- expression :: Expression relations grouping params (nullity 'PGfloat4)

513+-- expression = trunc pi

514+-- in renderExpression expression

515+-- :}

516+-- "trunc(pi())"

517+trunc

518+ :: PGFloating frac

519+ => Expression relations grouping params (nullity frac)

520+ -- ^ fractional number

521+ -> Expression relations grouping params (nullity frac)

522+trunc = unsafeFunction "trunc"

523+

524+-- | >>> :{

525+-- let

526+-- expression :: Expression relations grouping params (nullity 'PGfloat4)

527+-- expression = round_ pi

528+-- in renderExpression expression

529+-- :}

530+-- "round(pi())"

531+round_

532+ :: PGFloating frac

533+ => Expression relations grouping params (nullity frac)

534+ -- ^ fractional number

535+ -> Expression relations grouping params (nullity frac)

536+round_ = unsafeFunction "round"

537+

538+-- | >>> :{

539+-- let

540+-- expression :: Expression relations grouping params (nullity 'PGfloat4)

541+-- expression = ceiling_ pi

542+-- in renderExpression expression

543+-- :}

544+-- "ceiling(pi())"

545+ceiling_

546+ :: PGFloating frac

547+ => Expression relations grouping params (nullity frac)

548+ -- ^ fractional number

549+ -> Expression relations grouping params (nullity frac)

550+ceiling_ = unsafeFunction "ceiling"

551+

552+-- | A `Condition` is a boolean valued `Expression`. While SQL allows

553+-- conditions to have @NULL@, Squeal instead chooses to disallow @NULL@,

554+-- forcing one to handle the case of @NULL@ explicitly to produce

555+-- a `Condition`.

556+type Condition relations grouping params =

557+ Expression relations grouping params ('NotNull 'PGbool)

558+

559+-- | >>> renderExpression true

560+-- "TRUE"

561+true :: Condition relations grouping params

562+true = UnsafeExpression "TRUE"

563+

564+-- | >>> renderExpression false

565+-- "FALSE"

566+false :: Condition relations grouping params

567+false = UnsafeExpression "FALSE"

568+

569+-- | >>> renderExpression $ not_ true

570+-- "(NOT TRUE)"

571+not_

572+ :: Condition relations grouping params

573+ -> Condition relations grouping params

574+not_ = unsafeUnaryOp "NOT"

575+

576+-- | >>> renderExpression $ true .&& false

577+-- "(TRUE AND FALSE)"

578+(.&&)

579+ :: Condition relations grouping params

580+ -> Condition relations grouping params

581+ -> Condition relations grouping params

582+(.&&) = unsafeBinaryOp "AND"

583+

584+-- | >>> renderExpression $ true .|| false

585+-- "(TRUE OR FALSE)"

586+(.||)

587+ :: Condition relations grouping params

588+ -> Condition relations grouping params

589+ -> Condition relations grouping params

590+(.||) = unsafeBinaryOp "OR"

591+

592+-- | >>> :{

593+-- let

594+-- expression :: Expression relations grouping params (nullity 'PGint2)

595+-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3

596+-- in renderExpression expression

597+-- :}

598+-- "CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END"

599+caseWhenThenElse

600+ :: [ ( Condition relations grouping params

601+ , Expression relations grouping params (ty)

602+ ) ]

603+ -- ^ whens and thens

604+ -> Expression relations grouping params (ty)

605+ -- ^ else

606+ -> Expression relations grouping params (ty)

607+caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat

608+ [ "CASE"

609+ , mconcat

610+ [ mconcat

611+ [ " WHEN ", renderExpression when_

612+ , " THEN ", renderExpression then_

613+ ]

614+ | (when_,then_) <- whenThens

615+ ]

616+ , " ELSE ", renderExpression else_

617+ , " END"

618+ ]

619+

620+-- | >>> :{

621+-- let

622+-- expression :: Expression relations grouping params (nullity 'PGint2)

623+-- expression = ifThenElse true 1 0

624+-- in renderExpression expression

625+-- :}

626+-- "CASE WHEN TRUE THEN 1 ELSE 0 END"

627+ifThenElse

628+ :: Condition relations grouping params

629+ -> Expression relations grouping params (ty) -- ^ then

630+ -> Expression relations grouping params (ty) -- ^ else

631+ -> Expression relations grouping params (ty)

632+ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_

633+

634+-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`

635+-- will produce @NULL@s if one of their arguments is @NULL@.

636+--

637+-- >>> renderExpression $ notNull true .== null_

638+-- "(TRUE = NULL)"

639+(.==)

640+ :: Expression relations grouping params (nullity ty) -- ^ lhs

641+ -> Expression relations grouping params (nullity ty) -- ^ rhs

642+ -> Expression relations grouping params (nullity 'PGbool)

643+(.==) = unsafeBinaryOp "="

644+infix 4 .==

645+

646+-- | >>> renderExpression $ notNull true ./= null_

647+-- "(TRUE <> NULL)"

648+(./=)

649+ :: Expression relations grouping params (nullity ty) -- ^ lhs

650+ -> Expression relations grouping params (nullity ty) -- ^ rhs

651+ -> Expression relations grouping params (nullity 'PGbool)

652+(./=) = unsafeBinaryOp "<>"

653+infix 4 ./=

654+

655+-- | >>> renderExpression $ notNull true .>= null_

656+-- "(TRUE >= NULL)"

657+(.>=)

658+ :: Expression relations grouping params (nullity ty) -- ^ lhs

659+ -> Expression relations grouping params (nullity ty) -- ^ rhs

660+ -> Expression relations grouping params (nullity 'PGbool)

661+(.>=) = unsafeBinaryOp ">="

662+infix 4 .>=

663+

664+-- | >>> renderExpression $ notNull true .< null_

665+-- "(TRUE < NULL)"

666+(.<)

667+ :: Expression relations grouping params (nullity ty) -- ^ lhs

668+ -> Expression relations grouping params (nullity ty) -- ^ rhs

669+ -> Expression relations grouping params (nullity 'PGbool)

670+(.<) = unsafeBinaryOp "<"

671+infix 4 .<

672+

673+-- | >>> renderExpression $ notNull true .<= null_

674+-- "(TRUE <= NULL)"

675+(.<=)

676+ :: Expression relations grouping params (nullity ty) -- ^ lhs

677+ -> Expression relations grouping params (nullity ty) -- ^ rhs

678+ -> Expression relations grouping params (nullity 'PGbool)

679+(.<=) = unsafeBinaryOp "<="

680+infix 4 .<=

681+

682+-- | >>> renderExpression $ notNull true .> null_

683+-- "(TRUE > NULL)"

684+(.>)

685+ :: Expression relations grouping params (nullity ty) -- ^ lhs

686+ -> Expression relations grouping params (nullity ty) -- ^ rhs

687+ -> Expression relations grouping params (nullity 'PGbool)

688+(.>) = unsafeBinaryOp ">"

689+infix 4 .>

690+

691+-- | >>> renderExpression currentDate

692+-- "CURRENT_DATE"

693+currentDate

694+ :: Expression relations grouping params (nullity 'PGdate)

695+currentDate = UnsafeExpression "CURRENT_DATE"

696+

697+-- | >>> renderExpression currentTime

698+-- "CURRENT_TIME"

699+currentTime

700+ :: Expression relations grouping params (nullity 'PGtimetz)

701+currentTime = UnsafeExpression "CURRENT_TIME"

702+

703+-- | >>> renderExpression currentTimestamp

704+-- "CURRENT_TIMESTAMP"

705+currentTimestamp

706+ :: Expression relations grouping params (nullity 'PGtimestamptz)

707+currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

708+

709+-- | >>> renderExpression localTime

710+-- "LOCALTIME"

711+localTime

712+ :: Expression relations grouping params (nullity 'PGtime)

713+localTime = UnsafeExpression "LOCALTIME"

714+

715+-- | >>> renderExpression localTimestamp

716+-- "LOCALTIMESTAMP"

717+localTimestamp

718+ :: Expression relations grouping params (nullity 'PGtimestamp)

719+localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

720+

721+{-----------------------------------------

722+text

723+-----------------------------------------}

438

724

439instance IsString

725instance IsString

440− (Expression outer commons grp schemas params from (null 'PGtext)) where

726+ (Expression relations grouping params (nullity 'PGtext)) where

441 fromString str = UnsafeExpression $

727 fromString str = UnsafeExpression $

442 "E\'" <> fromString (escape =<< str) <> "\'"

728 "E\'" <> fromString (escape =<< str) <> "\'"

443−instance IsString

729+ where

444− (Expression outer commons grp schemas params from (null 'PGtsvector)) where

730+ escape = \case

445− fromString str = UnsafeExpression . parenthesized . (<> " :: tsvector") $

731+ '\NUL' -> "\\0"

446− "E\'" <> fromString (escape =<< str) <> "\'"

732+ '\'' -> "''"

447−instance IsString

733+ '"' -> "\\\""

448− (Expression outer commons grp schemas params from (null 'PGtsquery)) where

734+ '\b' -> "\\b"

449− fromString str = UnsafeExpression . parenthesized . (<> " :: tsquery") $

735+ '\n' -> "\\n"

450− "E\'" <> fromString (escape =<< str) <> "\'"

736+ '\r' -> "\\r"

737+ '\t' -> "\\t"

738+ '\\' -> "\\\\"

739+ c -> [c]

451

740

452instance Semigroup

741instance Semigroup

453− (Expression outer commons grp schemas params from (null ('PGvararray ty))) where

742+ (Expression relations grouping params (nullity 'PGtext)) where

454− (<>) = unsafeBinaryOp "||"

455−instance Semigroup

456− (Expression outer commons grp schemas params from (null 'PGjsonb)) where

457− (<>) = unsafeBinaryOp "||"

458−instance Semigroup

459− (Expression outer commons grp schemas params from (null 'PGtext)) where

460− (<>) = unsafeBinaryOp "||"

461−instance Semigroup

462− (Expression outer commons grp schemas params from (null 'PGtsvector)) where

463 (<>) = unsafeBinaryOp "||"

743 (<>) = unsafeBinaryOp "||"

464

744

465instance Monoid

745instance Monoid

466− (Expression outer commons grp schemas params from (null 'PGtext)) where

746+ (Expression relations grouping params (nullity 'PGtext)) where

467− mempty = fromString ""

468− mappend = (<>)

469−instance Monoid

470− (Expression outer commons grp schemas params from (null 'PGtsvector)) where

471 mempty = fromString ""

747 mempty = fromString ""

472 mappend = (<>)

748 mappend = (<>)

749+

750+-- | >>> renderExpression $ lower "ARRRGGG"

751+-- "lower(E'ARRRGGG')"

752+lower

753+ :: Expression relations grouping params (nullity 'PGtext)

754+ -- ^ string to lower case

755+ -> Expression relations grouping params (nullity 'PGtext)

756+lower = unsafeFunction "lower"

757+

758+-- | >>> renderExpression $ upper "eeee"

759+-- "upper(E'eeee')"

760+upper

761+ :: Expression relations grouping params (nullity 'PGtext)

762+ -- ^ string to upper case

763+ -> Expression relations grouping params (nullity 'PGtext)

764+upper = unsafeFunction "upper"

765+

766+-- | >>> renderExpression $ charLength "four"

767+-- "char_length(E'four')"

768+charLength

769+ :: Expression relations grouping params (nullity 'PGtext)

770+ -- ^ string to measure

771+ -> Expression relations grouping params (nullity 'PGint4)

772+charLength = unsafeFunction "char_length"

773+

774+-- | The `like` expression returns true if the @string@ matches

775+-- the supplied @pattern@. If @pattern@ does not contain percent signs

776+-- or underscores, then the pattern only represents the string itself;

777+-- in that case `like` acts like the equals operator. An underscore (_)

778+-- in pattern stands for (matches) any single character; a percent sign (%)

779+-- matches any sequence of zero or more characters.

780+--

781+-- >>> renderExpression $ "abc" `like` "a%"

782+-- "(E'abc' LIKE E'a%')"

783+like

784+ :: Expression relations grouping params (nullity 'PGtext)

785+ -- ^ string

786+ -> Expression relations grouping params (nullity 'PGtext)

787+ -- ^ pattern

788+ -> Expression relations grouping params (nullity 'PGbool)

789+like = unsafeBinaryOp "LIKE"

790+

791+{-----------------------------------------

792+aggregation

793+-----------------------------------------}

794+

795+-- | escape hatch to define aggregate functions

796+unsafeAggregate

797+ :: ByteString -- ^ aggregate function

798+ -> Expression relations 'Ungrouped params (xty)

799+ -> Expression relations ('Grouped bys) params (yty)

800+unsafeAggregate fun x = UnsafeExpression $ mconcat

801+ [fun, "(", renderExpression x, ")"]

802+

803+-- | escape hatch to define aggregate functions over distinct values

804+unsafeAggregateDistinct

805+ :: ByteString -- ^ aggregate function

806+ -> Expression relations 'Ungrouped params (xty)

807+ -> Expression relations ('Grouped bys) params (yty)

808+unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat

809+ [fun, "(DISTINCT ", renderExpression x, ")"]

810+

811+-- | >>> :{

812+-- let

813+-- expression :: Expression '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Grouped bys) params ('Null 'PGnumeric)

814+-- expression = sum_ #col

815+-- in renderExpression expression

816+-- :}

817+-- "sum(\"col\")"

818+sum_

819+ :: PGNum ty

820+ => Expression relations 'Ungrouped params (nullity ty)

821+ -- ^ what to sum

822+ -> Expression relations ('Grouped bys) params (nullity ty)

823+sum_ = unsafeAggregate "sum"

824+

825+-- | >>> :{

826+-- let

827+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGnumeric]] ('Grouped bys) params (nullity 'PGnumeric)

828+-- expression = sumDistinct #col

829+-- in renderExpression expression

830+-- :}

831+-- "sum(DISTINCT \"col\")"

832+sumDistinct

833+ :: PGNum ty

834+ => Expression relations 'Ungrouped params (nullity ty)

835+ -- ^ what to sum

836+ -> Expression relations ('Grouped bys) params (nullity ty)

837+sumDistinct = unsafeAggregateDistinct "sum"

838+

839+-- | A constraint for `PGType`s that you can take averages of and the resulting

840+-- `PGType`.

841+class PGAvg ty avg | ty -> avg where

842+ avg, avgDistinct

843+ :: Expression relations 'Ungrouped params (nullity ty)

844+ -- ^ what to average

845+ -> Expression relations ('Grouped bys) params (nullity avg)

846+ avg = unsafeAggregate "avg"

847+ avgDistinct = unsafeAggregateDistinct "avg"

848+instance PGAvg 'PGint2 'PGnumeric

849+instance PGAvg 'PGint4 'PGnumeric

850+instance PGAvg 'PGint8 'PGnumeric

851+instance PGAvg 'PGnumeric 'PGnumeric

852+instance PGAvg 'PGfloat4 'PGfloat8

853+instance PGAvg 'PGfloat8 'PGfloat8

854+instance PGAvg 'PGinterval 'PGinterval

855+

856+-- | >>> :{

857+-- let

858+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

859+-- expression = bitAnd #col

860+-- in renderExpression expression

861+-- :}

862+-- "bit_and(\"col\")"

863+bitAnd

864+ :: PGIntegral int

865+ => Expression relations 'Ungrouped params (nullity int)

866+ -- ^ what to aggregate

867+ -> Expression relations ('Grouped bys) params (nullity int)

868+bitAnd = unsafeAggregate "bit_and"

869+

870+-- | >>> :{

871+-- let

872+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

873+-- expression = bitOr #col

874+-- in renderExpression expression

875+-- :}

876+-- "bit_or(\"col\")"

877+bitOr

878+ :: PGIntegral int

879+ => Expression relations 'Ungrouped params (nullity int)

880+ -- ^ what to aggregate

881+ -> Expression relations ('Grouped bys) params (nullity int)

882+bitOr = unsafeAggregate "bit_or"

883+

884+-- | >>> :{

885+-- let

886+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

887+-- expression = bitAndDistinct #col

888+-- in renderExpression expression

889+-- :}

890+-- "bit_and(DISTINCT \"col\")"

891+bitAndDistinct

892+ :: PGIntegral int

893+ => Expression relations 'Ungrouped params (nullity int)

894+ -- ^ what to aggregate

895+ -> Expression relations ('Grouped bys) params (nullity int)

896+bitAndDistinct = unsafeAggregateDistinct "bit_and"

897+

898+-- | >>> :{

899+-- let

900+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGint4]] (Grouped bys) params (nullity 'PGint4)

901+-- expression = bitOrDistinct #col

902+-- in renderExpression expression

903+-- :}

904+-- "bit_or(DISTINCT \"col\")"

905+bitOrDistinct

906+ :: PGIntegral int

907+ => Expression relations 'Ungrouped params (nullity int)

908+ -- ^ what to aggregate

909+ -> Expression relations ('Grouped bys) params (nullity int)

910+bitOrDistinct = unsafeAggregateDistinct "bit_or"

911+

912+-- | >>> :{

913+-- let

914+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

915+-- expression = boolAnd #col

916+-- in renderExpression expression

917+-- :}

918+-- "bool_and(\"col\")"

919+boolAnd

920+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

921+ -- ^ what to aggregate

922+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

923+boolAnd = unsafeAggregate "bool_and"

924+

925+-- | >>> :{

926+-- let

927+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

928+-- expression = boolOr #col

929+-- in renderExpression expression

930+-- :}

931+-- "bool_or(\"col\")"

932+boolOr

933+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

934+ -- ^ what to aggregate

935+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

936+boolOr = unsafeAggregate "bool_or"

937+

938+-- | >>> :{

939+-- let

940+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

941+-- expression = boolAndDistinct #col

942+-- in renderExpression expression

943+-- :}

944+-- "bool_and(DISTINCT \"col\")"

945+boolAndDistinct

946+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

947+ -- ^ what to aggregate

948+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

949+boolAndDistinct = unsafeAggregateDistinct "bool_and"

950+

951+-- | >>> :{

952+-- let

953+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

954+-- expression = boolOrDistinct #col

955+-- in renderExpression expression

956+-- :}

957+-- "bool_or(DISTINCT \"col\")"

958+boolOrDistinct

959+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

960+ -- ^ what to aggregate

961+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

962+boolOrDistinct = unsafeAggregateDistinct "bool_or"

963+

964+-- | A special aggregation that does not require an input

965+--

966+-- >>> renderExpression countStar

967+-- "count(*)"

968+countStar

969+ :: Expression relations ('Grouped bys) params ('NotNull 'PGint8)

970+countStar = UnsafeExpression $ "count(*)"

971+

972+-- | >>> :{

973+-- let

974+-- expression :: Expression '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

975+-- expression = count #col

976+-- in renderExpression expression

977+-- :}

978+-- "count(\"col\")"

979+count

980+ :: Expression relations 'Ungrouped params ty

981+ -- ^ what to count

982+ -> Expression relations ('Grouped bys) params ('NotNull 'PGint8)

983+count = unsafeAggregate "count"

984+

985+-- | >>> :{

986+-- let

987+-- expression :: Expression '[tab ::: '["col" ::: nullity ty]] (Grouped bys) params ('NotNull 'PGint8)

988+-- expression = countDistinct #col

989+-- in renderExpression expression

990+-- :}

991+-- "count(DISTINCT \"col\")"

992+countDistinct

993+ :: Expression relations 'Ungrouped params ty

994+ -- ^ what to count

995+ -> Expression relations ('Grouped bys) params ('NotNull 'PGint8)

996+countDistinct = unsafeAggregateDistinct "count"

997+

998+-- | synonym for `boolAnd`

999+--

1000+-- >>> :{

1001+-- let

1002+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1003+-- expression = every #col

1004+-- in renderExpression expression

1005+-- :}

1006+-- "every(\"col\")"

1007+every

1008+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

1009+ -- ^ what to aggregate

1010+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

1011+every = unsafeAggregate "every"

1012+

1013+-- | synonym for `boolAndDistinct`

1014+--

1015+-- >>> :{

1016+-- let

1017+-- expression :: Expression '[tab ::: '["col" ::: nullity 'PGbool]] (Grouped bys) params (nullity 'PGbool)

1018+-- expression = everyDistinct #col

1019+-- in renderExpression expression

1020+-- :}

1021+-- "every(DISTINCT \"col\")"

1022+everyDistinct

1023+ :: Expression relations 'Ungrouped params (nullity 'PGbool)

1024+ -- ^ what to aggregate

1025+ -> Expression relations ('Grouped bys) params (nullity 'PGbool)

1026+everyDistinct = unsafeAggregateDistinct "every"

1027+

1028+-- | minimum and maximum aggregation

1029+max_, min_, maxDistinct, minDistinct

1030+ :: Expression relations 'Ungrouped params (nullity ty)

1031+ -- ^ what to aggregate

1032+ -> Expression relations ('Grouped bys) params (nullity ty)

1033+max_ = unsafeAggregate "max"

1034+min_ = unsafeAggregate "min"

1035+maxDistinct = unsafeAggregateDistinct "max"

1036+minDistinct = unsafeAggregateDistinct "min"

1037+

1038+{-----------------------------------------

1039+tables

1040+-----------------------------------------}

1041+

1042+-- | A `Table` from a table expression is a way

1043+-- to call a table reference by its alias.

1044+newtype Table

1045+ (schema :: SchemaType)

1046+ (columns :: RelationType)

1047+ = UnsafeTable { renderTable :: ByteString }

1048+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

1049+instance

1050+ ( Has alias schema ('Table table)

1051+ , relation ~ ColumnsToRelation (TableToColumns table)

1052+ ) => IsLabel alias (Table schema relation) where

1053+ fromLabel = UnsafeTable $ renderAlias (Alias @alias)

1054+

1055+-- | A `View` from a table expression is a way

1056+-- to call a table reference by its alias.

1057+newtype View

1058+ (schema :: SchemaType)

1059+ (columns :: RelationType)

1060+ = UnsafeView { renderView :: ByteString }

1061+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

1062+instance

1063+ ( Has alias schema ('View columns)

1064+ ) => IsLabel alias (View schema columns) where

1065+ fromLabel = UnsafeView $ renderAlias (Alias @alias)

1066+

1067+{-----------------------------------------

1068+type expressions

1069+-----------------------------------------}

1070+

1071+-- | `TypeExpression`s are used in `cast`s and `createTable` commands.

1072+newtype TypeExpression (ty :: PGType)

1073+ = UnsafeTypeExpression { renderTypeExpression :: ByteString }

1074+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

1075+

1076+-- | logical Boolean (true/false)

1077+bool :: TypeExpression 'PGbool

1078+bool = UnsafeTypeExpression "bool"

1079+-- | signed two-byte integer

1080+int2, smallint :: TypeExpression 'PGint2

1081+int2 = UnsafeTypeExpression "int2"

1082+smallint = UnsafeTypeExpression "smallint"

1083+-- | signed four-byte integer

1084+int4, int, integer :: TypeExpression 'PGint4

1085+int4 = UnsafeTypeExpression "int4"

1086+int = UnsafeTypeExpression "int"

1087+integer = UnsafeTypeExpression "integer"

1088+-- | signed eight-byte integer

1089+int8, bigint :: TypeExpression 'PGint8

1090+int8 = UnsafeTypeExpression "int8"

1091+bigint = UnsafeTypeExpression "bigint"

1092+-- | arbitrary precision numeric type

1093+numeric :: TypeExpression 'PGnumeric

1094+numeric = UnsafeTypeExpression "numeric"

1095+-- | single precision floating-point number (4 bytes)

1096+float4, real :: TypeExpression 'PGfloat4

1097+float4 = UnsafeTypeExpression "float4"

1098+real = UnsafeTypeExpression "real"

1099+-- | double precision floating-point number (8 bytes)

1100+float8, doublePrecision :: TypeExpression 'PGfloat8

1101+float8 = UnsafeTypeExpression "float8"

1102+doublePrecision = UnsafeTypeExpression "double precision"

1103+-- | variable-length character string

1104+text :: TypeExpression 'PGtext

1105+text = UnsafeTypeExpression "text"

1106+-- | fixed-length character string

1107+char, character

1108+ :: (KnownNat n, 1 <= n)

1109+ => proxy n

1110+ -> TypeExpression ('PGchar n)

1111+char p = UnsafeTypeExpression $ "char(" <> renderNat p <> ")"

1112+character p = UnsafeTypeExpression $ "character(" <> renderNat p <> ")"

1113+-- | variable-length character string

1114+varchar, characterVarying

1115+ :: (KnownNat n, 1 <= n)

1116+ => proxy n

1117+ -> TypeExpression ('PGvarchar n)

1118+varchar p = UnsafeTypeExpression $ "varchar(" <> renderNat p <> ")"

1119+characterVarying p = UnsafeTypeExpression $

1120+ "character varying(" <> renderNat p <> ")"

1121+-- | binary data ("byte array")

1122+bytea :: TypeExpression 'PGbytea

1123+bytea = UnsafeTypeExpression "bytea"

1124+-- | date and time (no time zone)

1125+timestamp :: TypeExpression 'PGtimestamp

1126+timestamp = UnsafeTypeExpression "timestamp"

1127+-- | date and time, including time zone

1128+timestampWithTimeZone :: TypeExpression 'PGtimestamptz

1129+timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

1130+-- | calendar date (year, month, day)

1131+date :: TypeExpression 'PGdate

1132+date = UnsafeTypeExpression "date"

1133+-- | time of day (no time zone)

1134+time :: TypeExpression 'PGtime

1135+time = UnsafeTypeExpression "time"

1136+-- | time of day, including time zone

1137+timeWithTimeZone :: TypeExpression 'PGtimetz

1138+timeWithTimeZone = UnsafeTypeExpression "time with time zone"

1139+-- | time span

1140+interval :: TypeExpression 'PGinterval

1141+interval = UnsafeTypeExpression "interval"

1142+-- | universally unique identifier

1143+uuid :: TypeExpression 'PGuuid

1144+uuid = UnsafeTypeExpression "uuid"

1145+-- | IPv4 or IPv6 host address

1146+inet :: TypeExpression 'PGinet

1147+inet = UnsafeTypeExpression "inet"

1148+-- | textual JSON data

1149+json :: TypeExpression 'PGjson

1150+json = UnsafeTypeExpression "json"

1151+-- | binary JSON data, decomposed

1152+jsonb :: TypeExpression 'PGjsonb

1153+jsonb = UnsafeTypeExpression "jsonb"

1154+-- | variable length array

1155+vararray

1156+ :: TypeExpression pg

1157+ -> TypeExpression ('PGvararray pg)

1158+vararray ty = UnsafeTypeExpression $ renderTypeExpression ty <> "[]"

1159+-- | fixed length array

1160+--

1161+-- >>> renderTypeExpression (fixarray (Proxy @2) json)

1162+-- "json[2]"

1163+fixarray

1164+ :: KnownNat n

1165+ => proxy n

1166+ -> TypeExpression pg

1167+ -> TypeExpression ('PGfixarray n pg)

1168+fixarray p ty = UnsafeTypeExpression $

1169+ renderTypeExpression ty <> "[" <> renderNat p <> "]"

1170+

1171+-- | `pgtype` is a demoted version of a `PGType`

1172+class PGTyped (ty :: PGType) where pgtype :: TypeExpression ty

1173+instance PGTyped 'PGbool where pgtype = bool

1174+instance PGTyped 'PGint2 where pgtype = int2

1175+instance PGTyped 'PGint4 where pgtype = int4

1176+instance PGTyped 'PGint8 where pgtype = int8

1177+instance PGTyped 'PGnumeric where pgtype = numeric

1178+instance PGTyped 'PGfloat4 where pgtype = float4

1179+instance PGTyped 'PGfloat8 where pgtype = float8

1180+instance PGTyped 'PGtext where pgtype = text

1181+instance (KnownNat n, 1 <= n)

1182+ => PGTyped ('PGchar n) where pgtype = char (Proxy @n)

1183+instance (KnownNat n, 1 <= n)

1184+ => PGTyped ('PGvarchar n) where pgtype = varchar (Proxy @n)

1185+instance PGTyped 'PGbytea where pgtype = bytea

1186+instance PGTyped 'PGtimestamp where pgtype = timestamp

1187+instance PGTyped 'PGtimestamptz where pgtype = timestampWithTimeZone

1188+instance PGTyped 'PGdate where pgtype = date

1189+instance PGTyped 'PGtime where pgtype = time

1190+instance PGTyped 'PGtimetz where pgtype = timeWithTimeZone

1191+instance PGTyped 'PGinterval where pgtype = interval

1192+instance PGTyped 'PGuuid where pgtype = uuid

1193+instance PGTyped 'PGjson where pgtype = json

1194+instance PGTyped 'PGjsonb where pgtype = jsonb

1195+instance PGTyped ty => PGTyped ('PGvararray ty) where

1196+ pgtype = vararray (pgtype @ty)

1197+instance (KnownNat n, PGTyped ty) => PGTyped ('PGfixarray n ty) where

1198+ pgtype = fixarray (Proxy @n) (pgtype @ty)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Aggregate.hsdeleted−462

@@ -1,462 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Aggregate

3−Description: Aggregate functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Aggregate functions

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , DeriveGeneric

14− , FlexibleContexts

15− , FlexibleInstances

16− , FunctionalDependencies

17− , LambdaCase

18− , MultiParamTypeClasses

19− , OverloadedStrings

20− , PolyKinds

21− , TypeFamilies

22− , TypeOperators

23− , UndecidableInstances

24−#-}

25−

26−module Squeal.PostgreSQL.Expression.Aggregate

27− ( Aggregate (..)

28− , Distinction (..)

29− , PGSum

30− , PGAvg

31− ) where

32−

33−import Control.DeepSeq

34−import Data.ByteString (ByteString)

35−import Data.Kind

36−import GHC.TypeLits

37−

38−import qualified GHC.Generics as GHC

39−import qualified Generics.SOP as SOP

40−

41−import Squeal.PostgreSQL.Alias

42−import Squeal.PostgreSQL.Expression

43−import Squeal.PostgreSQL.List

44−import Squeal.PostgreSQL.Render

45−import Squeal.PostgreSQL.Schema

46−

47−-- $setup

48−-- >>> import Squeal.PostgreSQL

49−

50−{- |

51−`Aggregate` functions compute a single result from a set of input values.

52−`Aggregate` functions can be used as `GroupedBy` `Expression`s as well

53−as `Squeal.PostgreSQL.Expression.Window.WindowFunction`s.

54−-}

55−class Aggregate expr1 exprN aggr

56− | aggr -> expr1, aggr -> exprN where

57−

58− -- | A special aggregation that does not require an input

59− --

60− -- >>> :{

61− -- let

62− -- expression :: Expression '[] commons ('Grouped bys) schemas params from ('NotNull 'PGint8)

63− -- expression = countStar

64− -- in printSQL expression

65− -- :}

66− -- count(*)

67− countStar :: aggr ('NotNull 'PGint8)

68−

69− -- | >>> :{

70− -- let

71− -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null ty]] ('NotNull 'PGint8)

72− -- expression = count (All #col)

73− -- in printSQL expression

74− -- :}

75− -- count(ALL "col")

76− count

77− :: expr1 ty

78− -- ^ what to count

79− -> aggr ('NotNull 'PGint8)

80−

81− -- | >>> :{

82− -- let

83− -- expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: 'Null 'PGnumeric]] ('Null 'PGnumeric)

84− -- expression = sum_ (Distinct #col)

85− -- in printSQL expression

86− -- :}

87− -- sum(DISTINCT "col")

88− sum_

89− :: expr1 (null ty)

90− -> aggr ('Null (PGSum ty))

91−

92− -- | input values, including nulls, concatenated into an array

93− arrayAgg

94− :: expr1 ty

95− -> aggr ('Null ('PGvararray ty))

96−

97− -- | aggregates values as a JSON array

98− jsonAgg

99− :: expr1 ty

100− -> aggr ('Null 'PGjson)

101−

102− -- | aggregates values as a JSON array

103− jsonbAgg

104− :: expr1 ty

105− -> aggr ('Null 'PGjsonb)

106−

107− {- |

108− the bitwise AND of all non-null input values, or null if none

109−

110− >>> :{

111− let

112− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)

113− expression = bitAnd (Distinct #col)

114− in printSQL expression

115− :}

116− bit_and(DISTINCT "col")

117− -}

118− bitAnd

119− :: int `In` PGIntegral

120− => expr1 (null int)

121− -- ^ what to aggregate

122− -> aggr ('Null int)

123−

124− {- |

125− the bitwise OR of all non-null input values, or null if none

126−

127− >>> :{

128− let

129− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGint4]] ('Null 'PGint4)

130− expression = bitOr (All #col)

131− in printSQL expression

132− :}

133− bit_or(ALL "col")

134− -}

135− bitOr

136− :: int `In` PGIntegral

137− => expr1 (null int)

138− -- ^ what to aggregate

139− -> aggr ('Null int)

140−

141− {- |

142− true if all input values are true, otherwise false

143−

144− >>> :{

145− let

146− winFun :: WindowFunction '[] commons 'Ungrouped schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

147− winFun = boolAnd #col

148− in printSQL winFun

149− :}

150− bool_and("col")

151− -}

152− boolAnd

153− :: expr1 (null 'PGbool)

154− -- ^ what to aggregate

155− -> aggr ('Null 'PGbool)

156−

157− {- |

158− true if at least one input value is true, otherwise false

159−

160− >>> :{

161− let

162− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

163− expression = boolOr (All #col)

164− in printSQL expression

165− :}

166− bool_or(ALL "col")

167− -}

168− boolOr

169− :: expr1 (null 'PGbool)

170− -- ^ what to aggregate

171− -> aggr ('Null 'PGbool)

172−

173− {- |

174− equivalent to `boolAnd`

175−

176− >>> :{

177− let

178− expression :: Expression '[] commons ('Grouped bys) schemas params '[tab ::: '["col" ::: null 'PGbool]] ('Null 'PGbool)

179− expression = every (Distinct #col)

180− in printSQL expression

181− :}

182− every(DISTINCT "col")

183− -}

184− every

185− :: expr1 (null 'PGbool)

186− -- ^ what to aggregate

187− -> aggr ('Null 'PGbool)

188−

189− {- |maximum value of expression across all input values-}

190− max_

191− :: expr1 (null ty)

192− -- ^ what to maximize

193− -> aggr ('Null ty)

194−

195− -- | minimum value of expression across all input values

196− min_

197− :: expr1 (null ty)

198− -- ^ what to minimize

199− -> aggr ('Null ty)

200−

201− -- | the average (arithmetic mean) of all input values

202− avg

203− :: expr1 (null ty)

204− -- ^ what to average

205− -> aggr ('Null (PGAvg ty))

206−

207− {- | correlation coefficient

208−

209− >>> :{

210− let

211− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

212− expression = corr (All (#y *: #x))

213− in printSQL expression

214− :}

215− corr(ALL "y", "x")

216− -}

217− corr

218− :: exprN '[null 'PGfloat8, null 'PGfloat8]

219− -> aggr ('Null 'PGfloat8)

220−

221− {- | population covariance

222−

223− >>> :{

224− let

225− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

226− expression = covarPop (All (#y *: #x))

227− in printSQL expression

228− :}

229− covar_pop(ALL "y", "x")

230− -}

231− covarPop

232− :: exprN '[null 'PGfloat8, null 'PGfloat8]

233− -> aggr ('Null 'PGfloat8)

234−

235− {- | sample covariance

236−

237− >>> :{

238− let

239− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

240− winFun = covarSamp (#y *: #x)

241− in printSQL winFun

242− :}

243− covar_samp("y", "x")

244− -}

245− covarSamp

246− :: exprN '[null 'PGfloat8, null 'PGfloat8]

247− -> aggr ('Null 'PGfloat8)

248−

249− {- | average of the independent variable (sum(X)/N)

250−

251− >>> :{

252− let

253− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

254− expression = regrAvgX (All (#y *: #x))

255− in printSQL expression

256− :}

257− regr_avgx(ALL "y", "x")

258− -}

259− regrAvgX

260− :: exprN '[null 'PGfloat8, null 'PGfloat8]

261− -> aggr ('Null 'PGfloat8)

262−

263− {- | average of the dependent variable (sum(Y)/N)

264−

265− >>> :{

266− let

267− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

268− winFun = regrAvgY (#y *: #x)

269− in printSQL winFun

270− :}

271− regr_avgy("y", "x")

272− -}

273− regrAvgY

274− :: exprN '[null 'PGfloat8, null 'PGfloat8]

275− -> aggr ('Null 'PGfloat8)

276−

277− {- | number of input rows in which both expressions are nonnull

278−

279− >>> :{

280− let

281− winFun :: WindowFunction '[] c 'Ungrouped s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGint8)

282− winFun = regrCount (#y *: #x)

283− in printSQL winFun

284− :}

285− regr_count("y", "x")

286− -}

287− regrCount

288− :: exprN '[null 'PGfloat8, null 'PGfloat8]

289− -> aggr ('Null 'PGint8)

290−

291− {- | y-intercept of the least-squares-fit linear equation determined by the (X, Y) pairs

292− >>> :{

293− let

294− expression :: Expression '[] c ('Grouped g) s p '[t ::: '["x" ::: 'NotNull 'PGfloat8, "y" ::: 'NotNull 'PGfloat8]] ('Null 'PGfloat8)

295− expression = regrIntercept (All (#y *: #x))

296− in printSQL expression

297− :}

298− regr_intercept(ALL "y", "x")

299− -}

300− regrIntercept

301− :: exprN '[null 'PGfloat8, null 'PGfloat8]

302− -> aggr ('Null 'PGfloat8)

303−

304− -- | @regr_r2(Y, X)@, square of the correlation coefficient

305− regrR2

306− :: exprN '[null 'PGfloat8, null 'PGfloat8]

307− -> aggr ('Null 'PGfloat8)

308−

309− -- | @regr_slope(Y, X)@, slope of the least-squares-fit linear equation

310− -- determined by the (X, Y) pairs

311− regrSlope

312− :: exprN '[null 'PGfloat8, null 'PGfloat8]

313− -> aggr ('Null 'PGfloat8)

314−

315− -- | @regr_sxx(Y, X)@, sum(X^2) - sum(X)^2/N

316− -- (“sum of squares” of the independent variable)

317− regrSxx

318− :: exprN '[null 'PGfloat8, null 'PGfloat8]

319− -> aggr ('Null 'PGfloat8)

320−

321− -- | @regr_sxy(Y, X)@, sum(X*Y) - sum(X) * sum(Y)/N

322− -- (“sum of products” of independent times dependent variable)

323− regrSxy

324− :: exprN '[null 'PGfloat8, null 'PGfloat8]

325− -> aggr ('Null 'PGfloat8)

326−

327− -- | @regr_syy(Y, X)@, sum(Y^2) - sum(Y)^2/N

328− -- (“sum of squares” of the dependent variable)

329− regrSyy

330− :: exprN '[null 'PGfloat8, null 'PGfloat8]

331− -> aggr ('Null 'PGfloat8)

332−

333− -- | historical alias for `stddevSamp`

334− stddev

335− :: expr1 (null ty)

336− -> aggr ('Null (PGAvg ty))

337−

338− -- | population standard deviation of the input values

339− stddevPop

340− :: expr1 (null ty)

341− -> aggr ('Null (PGAvg ty))

342−

343− -- | sample standard deviation of the input values

344− stddevSamp

345− :: expr1 (null ty)

346− -> aggr ('Null (PGAvg ty))

347−

348− -- | historical alias for `varSamp`

349− variance

350− :: expr1 (null ty)

351− -> aggr ('Null (PGAvg ty))

352−

353− -- | population variance of the input values

354− -- (square of the population standard deviation)

355− varPop

356− :: expr1 (null ty)

357− -> aggr ('Null (PGAvg ty))

358−

359− -- | sample variance of the input values

360− -- (square of the sample standard deviation)

361− varSamp

362− :: expr1 (null ty)

363− -> aggr ('Null (PGAvg ty))

364−

365−{- |

366−`Distinction`s are used for the input of `Aggregate` `Expression`s.

367−`All` invokes the aggregate once for each input row.

368−`Distinct` invokes the aggregate once for each distinct value of the expression

369−(or distinct set of values, for multiple expressions) found in the input

370−-}

371−data Distinction (expr :: kind -> Type) (ty :: kind)

372− = All (expr ty)

373− | Distinct (expr ty)

374− deriving (GHC.Generic,Show,Eq,Ord)

375−instance NFData (Distinction (Expression outer commons grp schemas params from) ty)

376−instance RenderSQL (Distinction (Expression outer commons grp schemas params from) ty) where

377− renderSQL = \case

378− All x -> "ALL" <+> renderSQL x

379− Distinct x -> "DISTINCT" <+> renderSQL x

380−instance SOP.SListI tys => RenderSQL

381− (Distinction (NP (Expression outer commons grp schemas params from)) tys) where

382− renderSQL = \case

383− All xs -> "ALL" <+> renderCommaSeparated renderSQL xs

384− Distinct xs -> "DISTINCT" <+> renderCommaSeparated renderSQL xs

385−

386−instance Aggregate

387− (Distinction (Expression outer commons 'Ungrouped schemas params from))

388− (Distinction (NP (Expression outer commons 'Ungrouped schemas params from)))

389− (Expression outer commons ('Grouped bys) schemas params from) where

390− countStar = UnsafeExpression "count(*)"

391− count = unsafeAggregate1 "count"

392− sum_ = unsafeAggregate1 "sum"

393− arrayAgg = unsafeAggregate1 "array_agg"

394− jsonAgg = unsafeAggregate1 "json_agg"

395− jsonbAgg = unsafeAggregate1 "jsonb_agg"

396− bitAnd = unsafeAggregate1 "bit_and"

397− bitOr = unsafeAggregate1 "bit_or"

398− boolAnd = unsafeAggregate1 "bool_and"

399− boolOr = unsafeAggregate1 "bool_or"

400− every = unsafeAggregate1 "every"

401− max_ = unsafeAggregate1 "max"

402− min_ = unsafeAggregate1 "min"

403− avg = unsafeAggregate1 "avg"

404− corr = unsafeAggregateN "corr"

405− covarPop = unsafeAggregateN "covar_pop"

406− covarSamp = unsafeAggregateN "covar_samp"

407− regrAvgX = unsafeAggregateN "regr_avgx"

408− regrAvgY = unsafeAggregateN "regr_avgy"

409− regrCount = unsafeAggregateN "regr_count"

410− regrIntercept = unsafeAggregateN "regr_intercept"

411− regrR2 = unsafeAggregateN "regr_r2"

412− regrSlope = unsafeAggregateN "regr_slope"

413− regrSxx = unsafeAggregateN "regr_sxx"

414− regrSxy = unsafeAggregateN "regr_sxy"

415− regrSyy = unsafeAggregateN "regr_syy"

416− stddev = unsafeAggregate1 "stddev"

417− stddevPop = unsafeAggregate1 "stddev_pop"

418− stddevSamp = unsafeAggregate1 "stddev_samp"

419− variance = unsafeAggregate1 "variance"

420− varPop = unsafeAggregate1 "var_pop"

421− varSamp = unsafeAggregate1 "var_samp"

422−

423−-- | escape hatch to define aggregate functions

424−unsafeAggregate1

425− :: ByteString -- ^ aggregate function

426− -> Distinction (Expression outer commons 'Ungrouped schemas params from) x

427− -> Expression outer commons ('Grouped bys) schemas params from y

428−unsafeAggregate1 fun x = UnsafeExpression $ fun <> parenthesized (renderSQL x)

429−

430−unsafeAggregateN

431− :: SOP.SListI xs

432− => ByteString -- ^ function

433− -> Distinction (NP (Expression outer commons 'Ungrouped schemas params from)) xs

434− -> Expression outer commons ('Grouped bys) schemas params from y

435−unsafeAggregateN fun xs = UnsafeExpression $ fun <> parenthesized (renderSQL xs)

436−

437−-- | A type family that calculates `PGSum``PGType` of

438−-- a given argument `PGType`.

439−type family PGSum ty where

440− PGSum 'PGint2 = 'PGint8

441− PGSum 'PGint4 = 'PGint8

442− PGSum 'PGint8 = 'PGnumeric

443− PGSum 'PGfloat4 = 'PGfloat4

444− PGSum 'PGfloat8 = 'PGfloat8

445− PGSum 'PGnumeric = 'PGnumeric

446− PGSum 'PGinterval = 'PGinterval

447− PGSum 'PGmoney = 'PGmoney

448− PGSum pg = TypeError

449− ( 'Text "Squeal type error: Cannot sum with argument type "

450− ':<>: 'ShowType pg )

451−

452−-- | A type family that calculates `PGAvg` type of a `PGType`.

453−type family PGAvg ty where

454− PGAvg 'PGint2 = 'PGnumeric

455− PGAvg 'PGint4 = 'PGnumeric

456− PGAvg 'PGint8 = 'PGnumeric

457− PGAvg 'PGnumeric = 'PGnumeric

458− PGAvg 'PGfloat4 = 'PGfloat8

459− PGAvg 'PGfloat8 = 'PGfloat8

460− PGAvg 'PGinterval = 'PGinterval

461− PGAvg pg = TypeError

462− ('Text "Squeal type error: No average for " ':<>: 'ShowType pg)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Collection.hsdeleted−169

@@ -1,169 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Collection

3−Description: Array and composite functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Array and composite functions

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DataKinds

14− , FlexibleContexts

15− , FlexibleInstances

16− , MultiParamTypeClasses

17− , OverloadedLabels

18− , OverloadedStrings

19− , RankNTypes

20− , ScopedTypeVariables

21− , TypeApplications

22− , TypeFamilies

23− , TypeOperators

24− , UndecidableInstances

25−#-}

26−

27−module Squeal.PostgreSQL.Expression.Collection

28− ( array

29− , array1

30− , array2

31− , cardinality

32− , index

33− , unnest

34− , row

35− , field

36− ) where

37−

38−import Data.String

39−import Data.Word (Word64)

40−

41−import qualified Generics.SOP as SOP

42−

43−import Squeal.PostgreSQL.Alias

44−import Squeal.PostgreSQL.Expression

45−import Squeal.PostgreSQL.Expression.Set

46−import Squeal.PostgreSQL.List

47−import Squeal.PostgreSQL.Render

48−import Squeal.PostgreSQL.Schema

49−

50−-- $setup

51−-- >>> import Squeal.PostgreSQL

52−

53−-- | >>> printSQL $ array [null_, false, true]

54−-- ARRAY[NULL, FALSE, TRUE]

55−array

56− :: [Expression outer commons grp schemas params from ty]

57− -- ^ array elements

58− -> Expression outer commons grp schemas params from (null ('PGvararray ty))

59−array xs = UnsafeExpression $ "ARRAY" <>

60− bracketed (commaSeparated (renderSQL <$> xs))

61−

62−{- | construct a 1-dimensional fixed length array

63−

64−>>> printSQL $ array1 (null_ :* false *: true)

65−ARRAY[NULL, FALSE, TRUE]

66−

67−>>> :type array1 (null_ :* false *: true)

68−array1 (null_ :* false *: true)

69− :: Expression

70− outer

71− commons

72− grp

73− schemas

74− params

75− from

76− (null ('PGfixarray '[3] ('Null 'PGbool)))

77−-}

78−array1

79− :: (n ~ Length tys, SOP.All ((~) ty) tys)

80− => NP (Expression outer commons grp schemas params from) tys

81− -> Expression outer commons grp schemas params from (null ('PGfixarray '[n] ty))

82−array1 xs = UnsafeExpression $ "ARRAY" <>

83− bracketed (renderCommaSeparated renderSQL xs)

84−

85−{- | construct a 2-dimensional fixed length array

86−

87−>>> printSQL $ array2 ((null_ :* false *: true) *: (false :* null_ *: true))

88−ARRAY[[NULL, FALSE, TRUE], [FALSE, NULL, TRUE]]

89−

90−>>> :type array2 ((null_ :* false *: true) *: (false :* null_ *: true))

91−array2 ((null_ :* false *: true) *: (false :* null_ *: true))

92− :: Expression

93− outer

94− commons

95− grp

96− schemas

97− params

98− from

99− (null ('PGfixarray '[2, 3] ('Null 'PGbool)))

100−-}

101−array2

102− :: ( SOP.All ((~) tys) tyss

103− , SOP.All SOP.SListI tyss

104− , Length tyss ~ n1

105− , SOP.All ((~) ty) tys

106− , Length tys ~ n2 )

107− => NP (NP (Expression outer commons grp schemas params from)) tyss

108− -> Expression outer commons grp schemas params from (null ('PGfixarray '[n1,n2] ty))

109−array2 xss = UnsafeExpression $ "ARRAY" <>

110− bracketed (renderCommaSeparatedConstraint @SOP.SListI (bracketed . renderCommaSeparated renderSQL) xss)

111−

112−-- | >>> printSQL $ cardinality (array [null_, false, true])

113−-- cardinality(ARRAY[NULL, FALSE, TRUE])

114−cardinality :: null ('PGvararray ty) --> null 'PGint8

115−cardinality = unsafeFunction "cardinality"

116−

117−-- | >>> printSQL $ array [null_, false, true] & index 2

118−-- (ARRAY[NULL, FALSE, TRUE])[2]

119−index

120− :: Word64 -- ^ index

121− -> null ('PGvararray ty) --> NullifyType ty

122−index n expr = UnsafeExpression $

123− parenthesized (renderSQL expr) <> "[" <> fromString (show n) <> "]"

124−

125−-- | Expand an array to a set of rows

126−unnest :: SetFunction "unnest" (null ('PGvararray ty)) '["unnest" ::: ty]

127−unnest = unsafeSetFunction

128−

129−-- | A row constructor is an expression that builds a row value

130−-- (also called a composite value) using values for its member fields.

131−--

132−-- >>> :{

133−-- type Complex = 'PGcomposite

134−-- '[ "real" ::: 'NotNull 'PGfloat8

135−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

136−-- :}

137−--

138−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer commons grp schemas params from ('NotNull Complex)

139−-- >>> printSQL i

140−-- ROW(0, 1)

141−row

142− :: SOP.SListI row

143− => NP (Aliased (Expression outer commons grp schemas params from)) row

144− -- ^ zero or more expressions for the row field values

145− -> Expression outer commons grp schemas params from (null ('PGcomposite row))

146−row exprs = UnsafeExpression $ "ROW" <> parenthesized

147− (renderCommaSeparated (\ (expr `As` _) -> renderSQL expr) exprs)

148−

149−-- | >>> :{

150−-- type Complex = 'PGcomposite

151−-- '[ "real" ::: 'NotNull 'PGfloat8

152−-- , "imaginary" ::: 'NotNull 'PGfloat8 ]

153−-- type Schema = '["complex" ::: 'Typedef Complex]

154−-- :}

155−--

156−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression outer '[] grp (Public Schema) from params ('NotNull Complex)

157−-- >>> printSQL $ i & field #complex #imaginary

158−-- (ROW(0, 1)::"complex")."imaginary"

159−field

160− :: ( Has sch schemas schema

161− , Has tydef schema ('Typedef ('PGcomposite row))

162− , Has field row ty)

163− => QualifiedAlias sch tydef -- ^ row type

164− -> Alias field -- ^ field name

165− -> Expression outer commons grp schemas params from ('NotNull ('PGcomposite row))

166− -> Expression outer commons grp schemas params from ty

167−field td fld expr = UnsafeExpression $

168− parenthesized (renderSQL expr <> "::" <> renderSQL td)

169− <> "." <> renderSQL fld

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Comparison.hsdeleted−206

@@ -1,206 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Comparison

3−Description: Comparison expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Comparison functions and operators

9−-}

10−

11−{-# LANGUAGE

12− OverloadedStrings

13− , RankNTypes

14− , TypeInType

15− , TypeOperators

16−#-}

17−

18−module Squeal.PostgreSQL.Expression.Comparison

19− ( (.==)

20− , (./=)

21− , (.>=)

22− , (.<)

23− , (.<=)

24− , (.>)

25− , greatest

26− , least

27− , BetweenExpr

28− , between

29− , notBetween

30− , betweenSymmetric

31− , notBetweenSymmetric

32− , isDistinctFrom

33− , isNotDistinctFrom

34− , isTrue

35− , isNotTrue

36− , isFalse

37− , isNotFalse

38− , isUnknown

39− , isNotUnknown

40− ) where

41−

42−import Data.ByteString

43−

44−import Squeal.PostgreSQL.Expression

45−import Squeal.PostgreSQL.Expression.Logic

46−import Squeal.PostgreSQL.Render

47−import Squeal.PostgreSQL.Schema

48−

49−-- $setup

50−-- >>> import Squeal.PostgreSQL

51−

52−-- | Comparison operations like `.==`, `./=`, `.>`, `.>=`, `.<` and `.<=`

53−-- will produce @NULL@s if one of their arguments is @NULL@.

54−--

55−-- >>> printSQL $ true .== null_

56−-- (TRUE = NULL)

57−(.==) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

58−(.==) = unsafeBinaryOp "="

59−infix 4 .==

60−

61−-- | >>> printSQL $ true ./= null_

62−-- (TRUE <> NULL)

63−(./=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

64−(./=) = unsafeBinaryOp "<>"

65−infix 4 ./=

66−

67−-- | >>> printSQL $ true .>= null_

68−-- (TRUE >= NULL)

69−(.>=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

70−(.>=) = unsafeBinaryOp ">="

71−infix 4 .>=

72−

73−-- | >>> printSQL $ true .< null_

74−-- (TRUE < NULL)

75−(.<) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

76−(.<) = unsafeBinaryOp "<"

77−infix 4 .<

78−

79−-- | >>> printSQL $ true .<= null_

80−-- (TRUE <= NULL)

81−(.<=) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

82−(.<=) = unsafeBinaryOp "<="

83−infix 4 .<=

84−

85−-- | >>> printSQL $ true .> null_

86−-- (TRUE > NULL)

87−(.>) :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

88−(.>) = unsafeBinaryOp ">"

89−infix 4 .>

90−

91−-- | >>> let expr = greatest [param @1] currentTimestamp :: Expression outer commons grp schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)

92−-- >>> printSQL expr

93−-- GREATEST(($1 :: timestamp with time zone), CURRENT_TIMESTAMP)

94−greatest :: FunctionVar ty ty ty

95−greatest = unsafeFunctionVar "GREATEST"

96−

97−-- | >>> printSQL $ least [null_] currentTimestamp

98−-- LEAST(NULL, CURRENT_TIMESTAMP)

99−least :: FunctionVar ty ty ty

100−least = unsafeFunctionVar "LEAST"

101−

102−{- |

103−A @RankNType@ for comparison expressions like `between`.

104−-}

105−type BetweenExpr

106− = forall outer commons grp schemas params from ty

107− . Expression outer commons grp schemas params from ty

108− -> ( Expression outer commons grp schemas params from ty

109− , Expression outer commons grp schemas params from ty ) -- ^ bounds

110− -> Condition outer commons grp schemas params from

111−

112−unsafeBetweenExpr :: ByteString -> BetweenExpr

113−unsafeBetweenExpr fun a (x,y) = UnsafeExpression $

114− renderSQL a <+> fun <+> renderSQL x <+> "AND" <+> renderSQL y

115−

116−{- | >>> printSQL $ true `between` (null_, false)

117−TRUE BETWEEN NULL AND FALSE

118−-}

119−between :: BetweenExpr

120−between = unsafeBetweenExpr "BETWEEN"

121−

122−{- | >>> printSQL $ true `notBetween` (null_, false)

123−TRUE NOT BETWEEN NULL AND FALSE

124−-}

125−notBetween :: BetweenExpr

126−notBetween = unsafeBetweenExpr "NOT BETWEEN"

127−

128−{- | between, after sorting the comparison values

129−

130−>>> printSQL $ true `betweenSymmetric` (null_, false)

131−TRUE BETWEEN SYMMETRIC NULL AND FALSE

132−-}

133−betweenSymmetric :: BetweenExpr

134−betweenSymmetric = unsafeBetweenExpr "BETWEEN SYMMETRIC"

135−

136−{- | not between, after sorting the comparison values

137−

138−>>> printSQL $ true `notBetweenSymmetric` (null_, false)

139−TRUE NOT BETWEEN SYMMETRIC NULL AND FALSE

140−-}

141−notBetweenSymmetric :: BetweenExpr

142−notBetweenSymmetric = unsafeBetweenExpr "NOT BETWEEN SYMMETRIC"

143−

144−{- | not equal, treating null like an ordinary value

145−

146−>>> printSQL $ true `isDistinctFrom` null_

147−(TRUE IS DISTINCT FROM NULL)

148−-}

149−isDistinctFrom :: Operator (null0 ty) (null1 ty) ('Null 'PGbool)

150−isDistinctFrom = unsafeBinaryOp "IS DISTINCT FROM"

151−

152−{- | equal, treating null like an ordinary value

153−

154−>>> printSQL $ true `isNotDistinctFrom` null_

155−(TRUE IS NOT DISTINCT FROM NULL)

156−-}

157−isNotDistinctFrom :: Operator (null0 ty) (null1 ty) ('NotNull 'PGbool)

158−isNotDistinctFrom = unsafeBinaryOp "IS NOT DISTINCT FROM"

159−

160−{- | is true

161−

162−>>> printSQL $ true & isTrue

163−(TRUE IS TRUE)

164−-}

165−isTrue :: null0 'PGbool --> null1 'PGbool

166−isTrue = unsafeRightOp "IS TRUE"

167−

168−{- | is false or unknown

169−

170−>>> printSQL $ true & isNotTrue

171−(TRUE IS NOT TRUE)

172−-}

173−isNotTrue :: null0 'PGbool --> null1 'PGbool

174−isNotTrue = unsafeRightOp "IS NOT TRUE"

175−

176−{- | is false

177−

178−>>> printSQL $ true & isFalse

179−(TRUE IS FALSE)

180−-}

181−isFalse :: null0 'PGbool --> null1 'PGbool

182−isFalse = unsafeRightOp "IS FALSE"

183−

184−{- | is true or unknown

185−

186−>>> printSQL $ true & isNotFalse

187−(TRUE IS NOT FALSE)

188−-}

189−isNotFalse :: null0 'PGbool --> null1 'PGbool

190−isNotFalse = unsafeRightOp "IS NOT FALSE"

191−

192−{- | is unknown

193−

194−>>> printSQL $ true & isUnknown

195−(TRUE IS UNKNOWN)

196−-}

197−isUnknown :: null0 'PGbool --> null1 'PGbool

198−isUnknown = unsafeRightOp "IS UNKNOWN"

199−

200−{- | is true or false

201−

202−>>> printSQL $ true & isNotUnknown

203−(TRUE IS NOT UNKNOWN)

204−-}

205−isNotUnknown :: null0 'PGbool --> null1 'PGbool

206−isNotUnknown = unsafeRightOp "IS NOT UNKNOWN"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Json.hsdeleted−462

@@ -1,462 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Json

3−Description: Json and Jsonb functions and operators

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Json and Jsonb functions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , FlexibleContexts

14− , FlexibleInstances

15− , GADTs

16− , OverloadedLabels

17− , OverloadedStrings

18− , PolyKinds

19− , RankNTypes

20− , ScopedTypeVariables

21− , TypeApplications

22− , TypeOperators

23− , UndecidableInstances

24− , UndecidableSuperClasses

25−#-}

26−

27−module Squeal.PostgreSQL.Expression.Json

28− ( -- * Json and Jsonb operators

29− (.->)

30− , (.->>)

31− , (.#>)

32− , (.#>>)

33− -- * Jsonb operators

34− , (.?)

35− , (.?|)

36− , (.?&)

37− , (.-.)

38− , (#-.)

39− -- * Json and Jsonb functions

40− , toJson

41− , toJsonb

42− , arrayToJson

43− , rowToJson

44− , jsonBuildArray

45− , jsonbBuildArray

46− , JsonBuildObject (..)

47− , jsonObject

48− , jsonbObject

49− , jsonZipObject

50− , jsonbZipObject

51− , jsonArrayLength

52− , jsonbArrayLength

53− , jsonTypeof

54− , jsonbTypeof

55− , jsonStripNulls

56− , jsonbStripNulls

57− , jsonbSet

58− , jsonbInsert

59− , jsonbPretty

60− -- * Json and Jsonb set returning functions

61− , jsonEach

62− , jsonbEach

63− , jsonEachText

64− , jsonbEachText

65− , jsonObjectKeys

66− , jsonbObjectKeys

67− , JsonPopulateFunction

68− , jsonPopulateRecord

69− , jsonbPopulateRecord

70− , jsonPopulateRecordSet

71− , jsonbPopulateRecordSet

72− , JsonToRecordFunction

73− , jsonToRecord

74− , jsonbToRecord

75− , jsonToRecordSet

76− , jsonbToRecordSet

77− ) where

78−

79−import Data.ByteString (ByteString)

80−import GHC.TypeLits

81−

82−import Squeal.PostgreSQL.Alias

83−import Squeal.PostgreSQL.Expression

84−import Squeal.PostgreSQL.Expression.Set

85−import Squeal.PostgreSQL.Expression.Type

86−import Squeal.PostgreSQL.List

87−import Squeal.PostgreSQL.Query

88−import Squeal.PostgreSQL.Render

89−import Squeal.PostgreSQL.Schema

90−

91−import qualified Generics.SOP as SOP

92−

93−-- $setup

94−-- >>> import Squeal.PostgreSQL

95−-- >>> import Data.Aeson

96−

97−{-----------------------------------------

98− -- json and jsonb support

99−

100−See https://www.postgresql.org/docs/10/static/functions-json.html -- most

101−comments lifted directly from this page.

102−

103−Table 9.44: json and jsonb operators

104−-----------------------------------------}

105−

106−-- | Get JSON value (object field or array element) at a key.

107−(.->)

108− :: (json `In` PGJsonType, key `In` PGJsonKey)

109− => Operator (null json) (null key) ('Null json)

110−infixl 8 .->

111−(.->) = unsafeBinaryOp "->"

112−

113−-- | Get JSON value (object field or array element) at a key, as text.

114−(.->>)

115− :: (json `In` PGJsonType, key `In` PGJsonKey)

116− => Operator (null json) (null key) ('Null 'PGtext)

117−infixl 8 .->>

118−(.->>) = unsafeBinaryOp "->>"

119−

120−-- | Get JSON value at a specified path.

121−(.#>)

122− :: json `In` PGJsonType

123− => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null json)

124−infixl 8 .#>

125−(.#>) = unsafeBinaryOp "#>"

126−

127−-- | Get JSON value at a specified path as text.

128−(.#>>)

129− :: json `In` PGJsonType

130− => Operator (null json) (null ('PGvararray ('NotNull 'PGtext))) ('Null 'PGtext)

131−infixl 8 .#>>

132−(.#>>) = unsafeBinaryOp "#>>"

133−

134−-- Additional jsonb operators

135−

136−-- | Does the string exist as a top-level key within the JSON value?

137−(.?) :: Operator (null 'PGjsonb) (null 'PGtext) ('Null 'PGbool)

138−infixl 9 .?

139−(.?) = unsafeBinaryOp "?"

140−

141−-- | Do any of these array strings exist as top-level keys?

142−(.?|) :: Operator

143− (null 'PGjsonb)

144− (null ('PGvararray ('NotNull 'PGtext)))

145− ('Null 'PGbool)

146−infixl 9 .?|

147−(.?|) = unsafeBinaryOp "?|"

148−

149−-- | Do all of these array strings exist as top-level keys?

150−(.?&) :: Operator

151− (null 'PGjsonb)

152− (null ('PGvararray ('NotNull 'PGtext)))

153− ('Null 'PGbool)

154−infixl 9 .?&

155−(.?&) = unsafeBinaryOp "?&"

156−

157−-- | Delete a key or keys from a JSON object, or remove an array element.

158−--

159−-- If the right operand is

160−--

161−-- @ text @: Delete key / value pair or string element from left operand.

162−-- Key / value pairs are matched based on their key value,

163−--

164−-- @ text[] @: Delete multiple key / value pairs or string elements

165−-- from left operand. Key / value pairs are matched based on their key value,

166−--

167−-- @ integer @: Delete the array element with specified index (Negative integers

168−-- count from the end). Throws an error if top level container is not an array.

169−(.-.)

170− :: key `In` '[ 'PGtext, 'PGvararray ('NotNull 'PGtext), 'PGint4, 'PGint2 ]

171− => Operator (null 'PGjsonb) (null key) (null 'PGjsonb)

172−infixl 6 .-.

173−(.-.) = unsafeBinaryOp "-"

174−

175−-- | Delete the field or element with specified path (for JSON arrays, negative

176−-- integers count from the end)

177−(#-.) :: Operator (null 'PGjsonb) (null ('PGvararray ('NotNull 'PGtext))) (null 'PGjsonb)

178−infixl 6 #-.

179−(#-.) = unsafeBinaryOp "#-"

180−

181−{-----------------------------------------

182−Table 9.45: JSON creation functions

183−-----------------------------------------}

184−

185−-- | Returns the value as json. Arrays and composites are converted

186−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

187−-- type to json, the cast function will be used to perform the conversion;

188−-- otherwise, a scalar value is produced. For any scalar type other than a

189−-- number, a Boolean, or a null value, the text representation will be used, in

190−-- such a fashion that it is a valid json value.

191−toJson :: null ty --> null 'PGjson

192−toJson = unsafeFunction "to_json"

193−

194−-- | Returns the value as jsonb. Arrays and composites are converted

195−-- (recursively) to arrays and objects; otherwise, if there is a cast from the

196−-- type to json, the cast function will be used to perform the conversion;

197−-- otherwise, a scalar value is produced. For any scalar type other than a

198−-- number, a Boolean, or a null value, the text representation will be used, in

199−-- such a fashion that it is a valid jsonb value.

200−toJsonb :: null ty --> null 'PGjsonb

201−toJsonb = unsafeFunction "to_jsonb"

202−

203−-- | Returns the array as a JSON array. A PostgreSQL multidimensional array

204−-- becomes a JSON array of arrays.

205−arrayToJson :: null ('PGvararray ty) --> null 'PGjson

206−arrayToJson = unsafeFunction "array_to_json"

207−

208−-- | Returns the row as a JSON object.

209−rowToJson :: null ('PGcomposite ty) --> null 'PGjson

210−rowToJson = unsafeFunction "row_to_json"

211−

212−-- | Builds a possibly-heterogeneously-typed JSON array out of a variadic

213−-- argument list.

214−jsonBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjson

215−jsonBuildArray = unsafeFunctionN "json_build_array"

216−

217−-- | Builds a possibly-heterogeneously-typed (binary) JSON array out of a

218−-- variadic argument list.

219−jsonbBuildArray :: SOP.SListI tuple => tuple ---> null 'PGjsonb

220−jsonbBuildArray = unsafeFunctionN "jsonb_build_array"

221−

222−-- | Builds a possibly-heterogeneously-typed JSON object out of a variadic

223−-- argument list. The elements of the argument list must alternate between text

224−-- and values.

225−class SOP.SListI tys => JsonBuildObject tys where

226−

227− jsonBuildObject :: tys ---> null 'PGjson

228− jsonBuildObject = unsafeFunctionN "json_build_object"

229−

230− jsonbBuildObject :: tys ---> null 'PGjsonb

231− jsonbBuildObject = unsafeFunctionN "jsonb_build_object"

232−

233−instance JsonBuildObject '[]

234−instance (JsonBuildObject tys, key `In` PGJsonKey)

235− => JsonBuildObject ('NotNull key ': value ': tys)

236−

237−-- | Builds a JSON object out of a text array.

238−-- The array must have two dimensions

239−-- such that each inner array has exactly two elements,

240−-- which are taken as a key/value pair.

241−jsonObject

242− :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))

243− --> null 'PGjson

244−jsonObject = unsafeFunction "json_object"

245−

246−-- | Builds a binary JSON object out of a text array.

247−-- The array must have two dimensions

248−-- such that each inner array has exactly two elements,

249−-- which are taken as a key/value pair.

250−jsonbObject

251− :: null ('PGfixarray '[n,2] ('NotNull 'PGtext))

252− --> null 'PGjsonb

253−jsonbObject = unsafeFunction "jsonb_object"

254−

255−-- | This is an alternate form of 'jsonObject' that takes two arrays; one for

256−-- keys and one for values, that are zipped pairwise to create a JSON object.

257−jsonZipObject ::

258− '[ null ('PGvararray ('NotNull 'PGtext))

259− , null ('PGvararray ('NotNull 'PGtext)) ]

260− ---> null 'PGjson

261−jsonZipObject = unsafeFunctionN "json_object"

262−

263−-- | This is an alternate form of 'jsonbObject' that takes two arrays; one for

264−-- keys and one for values, that are zipped pairwise to create a binary JSON

265−-- object.

266−jsonbZipObject ::

267− '[ null ('PGvararray ('NotNull 'PGtext))

268− , null ('PGvararray ('NotNull 'PGtext)) ]

269− ---> null 'PGjsonb

270−jsonbZipObject = unsafeFunctionN "jsonb_object"

271−

272−{-----------------------------------------

273−Table 9.46: JSON processing functions

274−-----------------------------------------}

275−

276−-- | Returns the number of elements in the outermost JSON array.

277−jsonArrayLength :: null 'PGjson --> null 'PGint4

278−jsonArrayLength = unsafeFunction "json_array_length"

279−

280−-- | Returns the number of elements in the outermost binary JSON array.

281−jsonbArrayLength :: null 'PGjsonb --> null 'PGint4

282−jsonbArrayLength = unsafeFunction "jsonb_array_length"

283−

284−-- | Returns the type of the outermost JSON value as a text string. Possible

285−-- types are object, array, string, number, boolean, and null.

286−jsonTypeof :: null 'PGjson --> null 'PGtext

287−jsonTypeof = unsafeFunction "json_typeof"

288−

289−-- | Returns the type of the outermost binary JSON value as a text string.

290−-- Possible types are object, array, string, number, boolean, and null.

291−jsonbTypeof :: null 'PGjsonb --> null 'PGtext

292−jsonbTypeof = unsafeFunction "jsonb_typeof"

293−

294−-- | Returns its argument with all object fields that have null values omitted.

295−-- Other null values are untouched.

296−jsonStripNulls :: null 'PGjson --> null 'PGjson

297−jsonStripNulls = unsafeFunction "json_strip_nulls"

298−

299−-- | Returns its argument with all object fields that have null values omitted.

300−-- Other null values are untouched.

301−jsonbStripNulls :: null 'PGjsonb --> null 'PGjsonb

302−jsonbStripNulls = unsafeFunction "jsonb_strip_nulls"

303−

304−-- | @ jsonbSet target path new_value create_missing @

305−--

306−-- Returns target with the section designated by path replaced by @new_value@,

307−-- or with @new_value@ added if create_missing is

308−-- `Squeal.PostgreSQL.Expression.Logic.true` and the

309−-- item designated by path does not exist. As with the path orientated

310−-- operators, negative integers that appear in path count from the end of JSON

311−-- arrays.

312−jsonbSet ::

313− '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))

314− , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb

315−jsonbSet = unsafeFunctionN "jsonbSet"

316−

317−-- | @ jsonbInsert target path new_value insert_after @

318−--

319−-- Returns target with @new_value@ inserted. If target section designated by

320−-- path is in a JSONB array, @new_value@ will be inserted before target or after

321−-- if @insert_after@ is `Squeal.PostgreSQL.Expression.Logic.true`.

322−-- If target section designated by

323−-- path is in JSONB object, @new_value@ will be inserted only if target does not

324−-- exist. As with the path orientated operators, negative integers that appear

325−-- in path count from the end of JSON arrays.

326−jsonbInsert ::

327− '[ null 'PGjsonb, null ('PGvararray ('NotNull 'PGtext))

328− , null 'PGjsonb, null 'PGbool ] ---> null 'PGjsonb

329−jsonbInsert = unsafeFunctionN "jsonb_insert"

330−

331−-- | Returns its argument as indented JSON text.

332−jsonbPretty :: null 'PGjsonb --> null 'PGtext

333−jsonbPretty = unsafeFunction "jsonb_pretty"

334−

335−{- | Expands the outermost JSON object into a set of key/value pairs.

336−

337−>>> printSQL (select Star (from (jsonEach (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

338−SELECT * FROM json_each(('{"a":"foo","b":"bar"}' :: json))

339−-}

340−jsonEach :: SetFunction "json_each" (null 'PGjson)

341− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

342−jsonEach = unsafeSetFunction

343−

344−{- | Expands the outermost binary JSON object into a set of key/value pairs.

345−

346−>>> printSQL (select Star (from (jsonbEach (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

347−SELECT * FROM jsonb_each(('{"a":"foo","b":"bar"}' :: jsonb))

348−-}

349−jsonbEach

350− :: SetFunction "jsonb_each" (nullity 'PGjsonb)

351− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGjson]

352−jsonbEach = unsafeSetFunction

353−

354−{- | Expands the outermost JSON object into a set of key/value pairs.

355−

356−>>> printSQL (select Star (from (jsonEachText (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))))

357−SELECT * FROM json_each_text(('{"a":"foo","b":"bar"}' :: json))

358−-}

359−jsonEachText

360− :: SetFunction "json_each_text" (null 'PGjson)

361− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

362−jsonEachText = unsafeSetFunction

363−

364−{- | Expands the outermost binary JSON object into a set of key/value pairs.

365−

366−>>> printSQL (select Star (from (jsonbEachText (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))))

367−SELECT * FROM jsonb_each_text(('{"a":"foo","b":"bar"}' :: jsonb))

368−-}

369−jsonbEachText

370− :: SetFunction "jsonb_each_text" (null 'PGjsonb)

371− '["key" ::: 'NotNull 'PGtext, "value" ::: 'NotNull 'PGtext]

372−jsonbEachText = unsafeSetFunction

373−

374−{- | Returns set of keys in the outermost JSON object.

375−

376−>>> printSQL (jsonObjectKeys (literal (Json (object ["a" .= "foo", "b" .= "bar"]))))

377−json_object_keys(('{"a":"foo","b":"bar"}' :: json))

378−-}

379−jsonObjectKeys

380− :: SetFunction "json_object_keys" (nullity 'PGjson)

381− '["json_object_keys" ::: 'NotNull 'PGtext]

382−jsonObjectKeys = unsafeSetFunction

383−

384−{- | Returns set of keys in the outermost JSON object.

385−

386−>>> printSQL (jsonbObjectKeys (literal (Jsonb (object ["a" .= "foo", "b" .= "bar"]))))

387−jsonb_object_keys(('{"a":"foo","b":"bar"}' :: jsonb))

388−-}

389−jsonbObjectKeys

390− :: SetFunction "jsonb_object_keys" (null 'PGjsonb)

391− '["jsonb_object_keys" ::: 'NotNull 'PGtext]

392−jsonbObjectKeys = unsafeSetFunction

393−

394−-- | Build rows from Json types.

395−type JsonPopulateFunction fun json

396− = forall schemas row outer commons params

397− . json `In` PGJsonType

398− => TypeExpression schemas ('NotNull ('PGcomposite row)) -- ^ row type

399− -> Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

400− -- ^ json type

401− -> FromClause outer commons schemas params '[fun ::: row]

402−

403−unsafePopulateFunction

404− :: forall fun ty

405− . KnownSymbol fun => Alias fun -> JsonPopulateFunction fun ty

406−unsafePopulateFunction _fun ty expr = UnsafeFromClause $ renderSymbol @fun

407− <> parenthesized ("null::" <> renderSQL ty <> ", " <> renderSQL expr)

408−

409−-- | Expands the JSON expression to a row whose columns match the record

410−-- type defined by the given table.

411−jsonPopulateRecord :: JsonPopulateFunction "json_populate_record" 'PGjson

412−jsonPopulateRecord = unsafePopulateFunction #json_populate_record

413−

414−-- | Expands the binary JSON expression to a row whose columns match the record

415−-- type defined by the given table.

416−jsonbPopulateRecord :: JsonPopulateFunction "jsonb_populate_record" 'PGjsonb

417−jsonbPopulateRecord = unsafePopulateFunction #jsonb_populate_record

418−

419−-- | Expands the outermost array of objects in the given JSON expression to a

420−-- set of rows whose columns match the record type defined by the given table.

421−jsonPopulateRecordSet :: JsonPopulateFunction "json_populate_record_set" 'PGjson

422−jsonPopulateRecordSet = unsafePopulateFunction #json_populate_record_set

423−

424−-- | Expands the outermost array of objects in the given binary JSON expression

425−-- to a set of rows whose columns match the record type defined by the given

426−-- table.

427−jsonbPopulateRecordSet :: JsonPopulateFunction "jsonb_populate_record_set" 'PGjsonb

428−jsonbPopulateRecordSet = unsafePopulateFunction #jsonb_populate_record_set

429−

430−-- | Build rows from Json types.

431−type JsonToRecordFunction json

432− = forall outer commons schemas params tab row

433− . (SOP.SListI row, json `In` PGJsonType)

434− => Expression outer commons 'Ungrouped schemas params '[] ('NotNull json)

435− -- ^ json type

436− -> Aliased (NP (Aliased (TypeExpression schemas))) (tab ::: row)

437− -- ^ row type

438− -> FromClause outer commons schemas params '[tab ::: row]

439−

440−unsafeRecordFunction :: ByteString -> JsonToRecordFunction json

441−unsafeRecordFunction fun expr (types `As` tab) = UnsafeFromClause $

442− fun <> parenthesized (renderSQL expr) <+> "AS" <+> renderSQL tab

443− <> parenthesized (renderCommaSeparated renderTy types)

444− where

445− renderTy :: Aliased (TypeExpression schemas) ty -> ByteString

446− renderTy (ty `As` alias) = renderSQL alias <+> renderSQL ty

447−

448−-- | Builds an arbitrary record from a JSON object.

449−jsonToRecord :: JsonToRecordFunction 'PGjson

450−jsonToRecord = unsafeRecordFunction "json_to_record"

451−

452−-- | Builds an arbitrary record from a binary JSON object.

453−jsonbToRecord :: JsonToRecordFunction 'PGjsonb

454−jsonbToRecord = unsafeRecordFunction "jsonb_to_record"

455−

456−-- | Builds an arbitrary set of records from a JSON array of objects.

457−jsonToRecordSet :: JsonToRecordFunction 'PGjson

458−jsonToRecordSet = unsafeRecordFunction "json_to_record_set"

459−

460−-- | Builds an arbitrary set of records from a binary JSON array of objects.

461−jsonbToRecordSet :: JsonToRecordFunction 'PGjsonb

462−jsonbToRecordSet = unsafeRecordFunction "jsonb_to_record_set"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Literal.hsdeleted−87

@@ -1,87 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Literal

3−Description: Literal expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Literal expressions

9−-}

10−

11−{-# LANGUAGE

12− FlexibleContexts

13− , FlexibleInstances

14− , LambdaCase

15− , OverloadedStrings

16− , RankNTypes

17− , ScopedTypeVariables

18− , TypeApplications

19− , TypeSynonymInstances

20− , UndecidableInstances

21−#-}

22−

23−module Squeal.PostgreSQL.Expression.Literal (Literal (..)) where

24−

25−import ByteString.StrictBuilder (builderBytes)

26−import Data.ByteString.Lazy (toStrict)

27−import Data.Int

28−import Data.String

29−import Data.Text (Text)

30−

31−import qualified Data.Aeson as JSON

32−import qualified Data.Text as Text

33−import qualified Data.Text.Lazy as Lazy (Text)

34−import qualified Data.Text.Lazy as Lazy.Text

35−

36−import Squeal.PostgreSQL.Binary

37−import Squeal.PostgreSQL.Expression

38−import Squeal.PostgreSQL.Expression.Logic

39−import Squeal.PostgreSQL.PG

40−import Squeal.PostgreSQL.Render

41−

42−{- |

43−The `Literal` class allows embedding a Haskell value directly

44−as an `Expression` using `literal`.

45−

46−>>> printSQL (literal 'a')

47−E'a'

48−

49−>>> printSQL (literal (1 :: Double))

50−1.0

51−

52−>>> printSQL (literal (Json [1 :: Double, 2]))

53−('[1.0,2.0]' :: json)

54−

55−>>> printSQL (literal (Enumerated GT))

56−'GT'

57−-}

58−class Literal hask where literal :: hask -> Expr (null (PG hask))

59−instance Literal Bool where

60− literal = \case

61− True -> true

62− False -> false

63−instance JSON.ToJSON hask => Literal (Json hask) where

64− literal = UnsafeExpression . parenthesized . (<> " :: json")

65− . singleQuotedUtf8 . toStrict . JSON.encode . getJson

66−instance JSON.ToJSON hask => Literal (Jsonb hask) where

67− literal = UnsafeExpression . parenthesized . (<> " :: jsonb")

68− . singleQuotedUtf8 . toStrict . JSON.encode . getJsonb

69−instance Literal Char where

70− literal chr = UnsafeExpression $

71− "E\'" <> fromString (escape chr) <> "\'"

72−instance Literal String where literal = fromString

73−instance Literal Int16 where literal = fromIntegral

74−instance Literal Int32 where literal = fromIntegral

75−instance Literal Int64 where literal = fromIntegral

76−instance Literal Float where literal = fromRational . toRational

77−instance Literal Double where literal = fromRational . toRational

78−instance Literal Text where literal = fromString . Text.unpack

79−instance Literal Lazy.Text where literal = fromString . Lazy.Text.unpack

80−instance ToParam (Enumerated enum) (PG (Enumerated enum))

81− => Literal (Enumerated enum) where

82− literal

83− = UnsafeExpression

84− . singleQuotedUtf8

85− . builderBytes

86− . unK

87− . toParam @(Enumerated enum) @(PG (Enumerated enum))

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Logic.hsdeleted−105

@@ -1,105 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Logic

3−Description: Logical expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Logical expressions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , TypeOperators

15−#-}

16−

17−module Squeal.PostgreSQL.Expression.Logic

18− ( Condition

19− , true

20− , false

21− , not_

22− , (.&&)

23− , (.||)

24− , caseWhenThenElse

25− , ifThenElse

26− ) where

27−

28−import Squeal.PostgreSQL.Expression

29−import Squeal.PostgreSQL.Render

30−import Squeal.PostgreSQL.Schema

31−

32−-- | A `Condition` is an `Expression`, which can evaluate

33−-- to `true`, `false` or `Squeal.PostgreSQL.Null.null_`. This is because SQL uses

34−-- a three valued logic.

35−type Condition outer commons grp schemas params from =

36− Expression outer commons grp schemas params from ('Null 'PGbool)

37−

38−-- | >>> printSQL true

39−-- TRUE

40−true :: Expr (null 'PGbool)

41−true = UnsafeExpression "TRUE"

42−

43−-- | >>> printSQL false

44−-- FALSE

45−false :: Expr (null 'PGbool)

46−false = UnsafeExpression "FALSE"

47−

48−-- | >>> printSQL $ not_ true

49−-- (NOT TRUE)

50−not_ :: null 'PGbool --> null 'PGbool

51−not_ = unsafeLeftOp "NOT"

52−

53−-- | >>> printSQL $ true .&& false

54−-- (TRUE AND FALSE)

55−(.&&) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)

56−infixr 3 .&&

57−(.&&) = unsafeBinaryOp "AND"

58−

59−-- | >>> printSQL $ true .|| false

60−-- (TRUE OR FALSE)

61−(.||) :: Operator (null 'PGbool) (null 'PGbool) (null 'PGbool)

62−infixr 2 .||

63−(.||) = unsafeBinaryOp "OR"

64−

65−-- | >>> :{

66−-- let

67−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

68−-- expression = caseWhenThenElse [(true, 1), (false, 2)] 3

69−-- in printSQL expression

70−-- :}

71−-- CASE WHEN TRUE THEN 1 WHEN FALSE THEN 2 ELSE 3 END

72−caseWhenThenElse

73− :: [ ( Condition outer commons grp schemas params from

74− , Expression outer commons grp schemas params from ty

75− ) ]

76− -- ^ whens and thens

77− -> Expression outer commons grp schemas params from ty

78− -- ^ else

79− -> Expression outer commons grp schemas params from ty

80−caseWhenThenElse whenThens else_ = UnsafeExpression $ mconcat

81− [ "CASE"

82− , mconcat

83− [ mconcat

84− [ " WHEN ", renderSQL when_

85− , " THEN ", renderSQL then_

86− ]

87− | (when_,then_) <- whenThens

88− ]

89− , " ELSE ", renderSQL else_

90− , " END"

91− ]

92−

93−-- | >>> :{

94−-- let

95−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

96−-- expression = ifThenElse true 1 0

97−-- in printSQL expression

98−-- :}

99−-- CASE WHEN TRUE THEN 1 ELSE 0 END

100−ifThenElse

101− :: Condition outer commons grp schemas params from

102− -> Expression outer commons grp schemas params from ty -- ^ then

103− -> Expression outer commons grp schemas params from ty -- ^ else

104− -> Expression outer commons grp schemas params from ty

105−ifThenElse if_ then_ else_ = caseWhenThenElse [(if_,then_)] else_

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Math.hsdeleted−100

@@ -1,100 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Math

3−Description: Math expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Mathematical functions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , TypeOperators

15−#-}

16−

17−module Squeal.PostgreSQL.Expression.Math

18− ( atan2_

19− , quot_

20− , rem_

21− , trunc

22− , round_

23− , ceiling_

24− ) where

25−

26−import Squeal.PostgreSQL.Expression

27−import Squeal.PostgreSQL.List

28−import Squeal.PostgreSQL.Schema

29−

30−-- $setup

31−-- >>> import Squeal.PostgreSQL

32−

33−-- | >>> :{

34−-- let

35−-- expression :: Expr (null 'PGfloat4)

36−-- expression = atan2_ (pi *: 2)

37−-- in printSQL expression

38−-- :}

39−-- atan2(pi(), 2)

40−atan2_ :: float `In` PGFloating => '[ null float, null float] ---> null float

41−atan2_ = unsafeFunctionN "atan2"

42−

43−

44−-- | integer division, truncates the result

45−--

46−-- >>> :{

47−-- let

48−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

49−-- expression = 5 `quot_` 2

50−-- in printSQL expression

51−-- :}

52−-- (5 / 2)

53−quot_

54− :: int `In` PGIntegral

55− => Operator (null int) (null int) (null int)

56−quot_ = unsafeBinaryOp "/"

57−

58−-- | remainder upon integer division

59−--

60−-- >>> :{

61−-- let

62−-- expression :: Expression outer commons grp schemas params from (null 'PGint2)

63−-- expression = 5 `rem_` 2

64−-- in printSQL expression

65−-- :}

66−-- (5 % 2)

67−rem_

68− :: int `In` PGIntegral

69− => Operator (null int) (null int) (null int)

70−rem_ = unsafeBinaryOp "%"

71−

72−-- | >>> :{

73−-- let

74−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

75−-- expression = trunc pi

76−-- in printSQL expression

77−-- :}

78−-- trunc(pi())

79−trunc :: frac `In` PGFloating => null frac --> null frac

80−trunc = unsafeFunction "trunc"

81−

82−-- | >>> :{

83−-- let

84−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

85−-- expression = round_ pi

86−-- in printSQL expression

87−-- :}

88−-- round(pi())

89−round_ :: frac `In` PGFloating => null frac --> null frac

90−round_ = unsafeFunction "round"

91−

92−-- | >>> :{

93−-- let

94−-- expression :: Expression outer commons grp schemas params from (null 'PGfloat4)

95−-- expression = ceiling_ pi

96−-- in printSQL expression

97−-- :}

98−-- ceiling(pi())

99−ceiling_ :: frac `In` PGFloating => null frac --> null frac

100−ceiling_ = unsafeFunction "ceiling"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Null.hsdeleted−104

@@ -1,104 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Null

3−Description: Null

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Null values and null handling functions

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , TypeOperators

15−#-}

16−

17−module Squeal.PostgreSQL.Expression.Null

18− ( null_

19− , notNull

20− , coalesce

21− , fromNull

22− , isNull

23− , isNotNull

24− , matchNull

25− , nullIf

26− ) where

27−

28−import Squeal.PostgreSQL.Expression

29−import Squeal.PostgreSQL.Expression.Logic

30−import Squeal.PostgreSQL.Render

31−import Squeal.PostgreSQL.Schema

32−

33−-- $setup

34−-- >>> import Squeal.PostgreSQL

35−

36−-- | analagous to `Nothing`

37−--

38−-- >>> printSQL null_

39−-- NULL

40−null_ :: Expr ('Null ty)

41−null_ = UnsafeExpression "NULL"

42−

43−-- | analagous to `Just`

44−--

45−-- >>> printSQL $ notNull true

46−-- TRUE

47−notNull :: 'NotNull ty --> 'Null ty

48−notNull = UnsafeExpression . renderSQL

49−

50−-- | return the leftmost value which is not NULL

51−--

52−-- >>> printSQL $ coalesce [null_, true] false

53−-- COALESCE(NULL, TRUE, FALSE)

54−coalesce :: FunctionVar ('Null ty) ('NotNull ty) ('NotNull ty)

55−coalesce nullxs notNullx = UnsafeExpression $

56− "COALESCE" <> parenthesized (commaSeparated

57− ((renderSQL <$> nullxs) <> [renderSQL notNullx]))

58−

59−-- | analagous to `Data.Maybe.fromMaybe` using @COALESCE@

60−--

61−-- >>> printSQL $ fromNull true null_

62−-- COALESCE(NULL, TRUE)

63−fromNull

64− :: Expression outer commons grp schemas params from ('NotNull ty)

65− -- ^ what to convert @NULL@ to

66− -> Expression outer commons grp schemas params from ('Null ty)

67− -> Expression outer commons grp schemas params from ('NotNull ty)

68−fromNull notNullx nullx = coalesce [nullx] notNullx

69−

70−-- | >>> printSQL $ null_ & isNull

71−-- NULL IS NULL

72−isNull :: 'Null ty --> null 'PGbool

73−isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"

74−

75−-- | >>> printSQL $ null_ & isNotNull

76−-- NULL IS NOT NULL

77−isNotNull :: 'Null ty --> null 'PGbool

78−isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"

79−

80−-- | analagous to `maybe` using @IS NULL@

81−--

82−-- >>> printSQL $ matchNull true not_ null_

83−-- CASE WHEN NULL IS NULL THEN TRUE ELSE (NOT NULL) END

84−matchNull

85− :: Expression outer commons grp schemas params from (nullty)

86− -- ^ what to convert @NULL@ to

87− -> ( Expression outer commons grp schemas params from ('NotNull ty)

88− -> Expression outer commons grp schemas params from (nullty) )

89− -- ^ function to perform when @NULL@ is absent

90− -> Expression outer commons grp schemas params from ('Null ty)

91− -> Expression outer commons grp schemas params from (nullty)

92−matchNull y f x = ifThenElse (isNull x) y

93− (f (UnsafeExpression (renderSQL x)))

94−

95−{-| right inverse to `fromNull`, if its arguments are equal then

96−`nullIf` gives @NULL@.

97−

98−>>> :set -XTypeApplications -XDataKinds

99−>>> let expr = nullIf (false *: param @1) :: Expression outer commons grp schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)

100−>>> printSQL expr

101−NULLIF(FALSE, ($1 :: bool))

102−-}

103−nullIf :: '[ 'NotNull ty, 'NotNull ty] ---> 'Null ty

104−nullIf = unsafeFunctionN "NULLIF"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Parameter.hsdeleted−80

@@ -1,80 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Parameter

3−Description: Parameters

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Parameters, out-of-line data values

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DataKinds

14− , FlexibleContexts

15− , FlexibleInstances

16− , FunctionalDependencies

17− , KindSignatures

18− , MultiParamTypeClasses

19− , OverloadedStrings

20− , RankNTypes

21− , ScopedTypeVariables

22− , TypeApplications

23− , TypeOperators

24− , UndecidableInstances

25−#-}

26−

27−module Squeal.PostgreSQL.Expression.Parameter

28− ( HasParameter (parameter)

29− , param

30− ) where

31−

32−import GHC.TypeLits

33−

34−import Squeal.PostgreSQL.Expression

35−import Squeal.PostgreSQL.Expression.Type

36−import Squeal.PostgreSQL.Render

37−import Squeal.PostgreSQL.Schema

38−

39−-- $setup

40−-- >>> import Squeal.PostgreSQL

41−

42−{- | A `HasParameter` constraint is used to indicate a value that is

43−supplied externally to a SQL statement.

44−`Squeal.PostgreSQL.PQ.manipulateParams`,

45−`Squeal.PostgreSQL.PQ.queryParams` and

46−`Squeal.PostgreSQL.PQ.traversePrepared` support specifying data values

47−separately from the SQL command string, in which case `param`s are used to

48−refer to the out-of-line data values.

49−-}

50−class KnownNat n => HasParameter

51− (n :: Nat)

52− (params :: [NullityType])

53− (ty :: NullityType)

54− | n params -> ty where

55− -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.

56− --

57− -- >>> let expr = parameter @1 int4 :: Expression outer '[] grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

58− -- >>> printSQL expr

59− -- ($1 :: int4)

60− parameter

61− :: TypeExpression schemas ty

62− -> Expression outer commons grp schemas params from ty

63− parameter ty = UnsafeExpression $ parenthesized $

64− "$" <> renderNat @n <+> "::"

65− <+> renderSQL ty

66−instance {-# OVERLAPPING #-} HasParameter 1 (ty1:tys) ty1

67−instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)

68− => HasParameter n (ty' : params) ty

69−

70−-- | `param` takes a `Nat` using type application and for basic types,

71−-- infers a `TypeExpression`.

72−--

73−-- >>> let expr = param @1 :: Expression outer commons grp schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

74−-- >>> printSQL expr

75−-- ($1 :: int4)

76−param

77− :: forall n outer commons schemas params from grp ty

78− . (PGTyped schemas ty, HasParameter n params ty)

79− => Expression outer commons grp schemas params from ty -- ^ param

80−param = parameter @n (pgtype @schemas)

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Range.hsdeleted−230

@@ -1,230 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Range

3−Description: range types and functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Range types and functions

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DataKinds

14− , DeriveAnyClass

15− , DeriveGeneric

16− , DeriveFoldable

17− , DerivingStrategies

18− , DeriveTraversable

19− , FlexibleContexts

20− , FlexibleInstances

21− , LambdaCase

22− , MultiParamTypeClasses

23− , OverloadedLabels

24− , OverloadedStrings

25− , PatternSynonyms

26− , RankNTypes

27− , ScopedTypeVariables

28− , TypeApplications

29− , TypeFamilies

30− , TypeOperators

31− , UndecidableInstances

32−#-}

33−

34−module Squeal.PostgreSQL.Expression.Range

35− ( range

36− , Range (..)

37− , (<=..<=), (<..<), (<=..<), (<..<=)

38− , moreThan, atLeast, lessThan, atMost

39− , singleton, whole

40− , Bound (..)

41− , (.<@)

42− , (@>.)

43− , (<<@)

44− , (@>>)

45− , (&<)

46− , (&>)

47− , (-|-)

48− , (@+)

49− , (@*)

50− , (@-)

51− , lowerBound

52− , upperBound

53− , isEmpty

54− , lowerInc

55− , lowerInf

56− , upperInc

57− , upperInf

58− , rangeMerge

59− ) where

60−

61−import BinaryParser

62−import ByteString.StrictBuilder

63−import Data.Bits

64−import qualified GHC.Generics as GHC

65−import qualified Generics.SOP as SOP

66−import qualified PostgreSQL.Binary.Decoding as Decoding

67−

68−import Squeal.PostgreSQL.Binary

69−import Squeal.PostgreSQL.Expression

70−import Squeal.PostgreSQL.Expression.Type hiding (bool)

71−import Squeal.PostgreSQL.PG

72−import Squeal.PostgreSQL.Render

73−import Squeal.PostgreSQL.Schema

74−

75−-- $setup

76−-- >>> import Squeal.PostgreSQL

77−

78−-- | Construct a `range`

79−--

80−-- >>> printSQL $ range tstzrange (atLeast now)

81−-- tstzrange(now(), NULL, '[)')

82−-- >>> printSQL $ range numrange (0 <=..< 2*pi)

83−-- numrange(0, (2 * pi()), '[)')

84−-- >>> printSQL $ range int4range Empty

85−-- ('empty' :: int4range)

86−range

87− :: TypeExpression schemas (null ('PGrange ty))

88− -> Range (Expression outer commons grp schemas params from ('NotNull ty))

89− -> Expression outer commons grp schemas params from (null ('PGrange ty))

90−range ty = \case

91− Empty -> UnsafeExpression $ parenthesized

92− (emp <+> "::" <+> renderSQL ty)

93− NonEmpty l u -> UnsafeExpression $ renderSQL ty <> parenthesized

94− (commaSeparated (args l u))

95− where

96− emp = singleQuote <> "empty" <> singleQuote

97− args l u = [arg l, arg u, singleQuote <> bra l <> ket u <> singleQuote]

98− singleQuote = "\'"

99− arg = \case

100− Infinite -> "NULL"; Closed x -> renderSQL x; Open x -> renderSQL x

101− bra = \case Infinite -> "("; Closed _ -> "["; Open _ -> "("

102− ket = \case Infinite -> ")"; Closed _ -> "]"; Open _ -> ")"

103−

104−data Bound x = Infinite | Closed x | Open x

105− deriving

106− ( Eq, Ord, Show, Read, GHC.Generic

107− , Functor, Foldable, Traversable )

108−

109−data Range x = Empty | NonEmpty (Bound x) (Bound x)

110− deriving

111− ( Eq, Ord, Show, Read, GHC.Generic

112− , Functor, Foldable, Traversable )

113− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

114−type instance PG (Range x) = 'PGrange (PG x)

115−instance ToParam x pg => ToParam (Range x) ('PGrange pg) where

116− toParam rng = K $

117− word8 (setFlags rng 0) <>

118− case rng of

119− Empty -> mempty

120− NonEmpty lower upper -> putBound lower <> putBound upper

121− where

122− putBound = \case

123− Infinite -> mempty

124− Closed value -> putValue (unK (toParam @x @pg value))

125− Open value -> putValue (unK (toParam @x @pg value))

126− putValue value = int32BE (fromIntegral (builderLength value)) <> value

127− setFlags = \case

128− Empty -> (`setBit` 0)

129− NonEmpty lower upper ->

130− setLowerFlags lower . setUpperFlags upper

131− setLowerFlags = \case

132− Infinite -> (`setBit` 3)

133− Closed _ -> (`setBit` 1)

134− Open _ -> id

135− setUpperFlags = \case

136− Infinite -> (`setBit` 4)

137− Closed _ -> (`setBit` 2)

138− Open _ -> id

139−instance FromValue pg y => FromValue ('PGrange pg) (Range y) where

140− fromValue = do

141− flag <- byte

142− if testBit flag 0 then return Empty else do

143− lower <-

144− if testBit flag 3

145− then return Infinite

146− else do

147− len <- sized 4 Decoding.int

148− l <- sized len (fromValue @pg)

149− return $ if testBit flag 1 then Closed l else Open l

150− upper <-

151− if testBit flag 4

152− then return Infinite

153− else do

154− len <- sized 4 Decoding.int

155− l <- sized len (fromValue @pg)

156− return $ if testBit flag 2 then Closed l else Open l

157− return $ NonEmpty lower upper

158−

159−(<=..<=), (<..<), (<=..<), (<..<=) :: x -> x -> Range x

160−infix 4 <=..<=, <..<, <=..<, <..<=

161−x <=..<= y = NonEmpty (Closed x) (Closed y)

162−x <..< y = NonEmpty (Open x) (Open y)

163−x <=..< y = NonEmpty (Closed x) (Open y)

164−x <..<= y = NonEmpty (Open x) (Closed y)

165−

166−moreThan, atLeast, lessThan, atMost :: x -> Range x

167−moreThan x = NonEmpty (Open x) Infinite

168−atLeast x = NonEmpty (Closed x) Infinite

169−lessThan x = NonEmpty Infinite (Open x)

170−atMost x = NonEmpty Infinite (Closed x)

171−

172−singleton :: x -> Range x

173−singleton x = x <=..<= x

174−

175−whole :: Range x

176−whole = NonEmpty Infinite Infinite

177−

178−(.<@) :: Operator ('NotNull ty) (null ('PGrange ty)) ('Null 'PGbool)

179−(.<@) = unsafeBinaryOp "<@"

180−

181−(@>.) :: Operator (null ('PGrange ty)) ('NotNull ty) ('Null 'PGbool)

182−(@>.) = unsafeBinaryOp "<@"

183−

184−(<<@) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

185−(<<@) = unsafeBinaryOp "<<"

186−

187−(@>>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

188−(@>>) = unsafeBinaryOp ">>"

189−

190−(&<) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

191−(&<) = unsafeBinaryOp "&<"

192−

193−(&>) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

194−(&>) = unsafeBinaryOp "&>"

195−

196−(-|-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) ('Null 'PGbool)

197−(-|-) = unsafeBinaryOp "-|-"

198−

199−(@+) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

200−(@+) = unsafeBinaryOp "+"

201−

202−(@*) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

203−(@*) = unsafeBinaryOp "*"

204−

205−(@-) :: Operator (null ('PGrange ty)) (null ('PGrange ty)) (null ('PGrange ty))

206−(@-) = unsafeBinaryOp "-"

207−

208−lowerBound :: null ('PGrange ty) --> 'Null ty

209−lowerBound = unsafeFunction "lower"

210−

211−upperBound :: null ('PGrange ty) --> 'Null ty

212−upperBound = unsafeFunction "upper"

213−

214−isEmpty :: null ('PGrange ty) --> 'Null 'PGbool

215−isEmpty = unsafeFunction "isempty"

216−

217−lowerInc :: null ('PGrange ty) --> 'Null 'PGbool

218−lowerInc = unsafeFunction "lower_inc"

219−

220−lowerInf :: null ('PGrange ty) --> 'Null 'PGbool

221−lowerInf = unsafeFunction "lower_inf"

222−

223−upperInc :: null ('PGrange ty) --> 'Null 'PGbool

224−upperInc = unsafeFunction "upper_inc"

225−

226−upperInf :: null ('PGrange ty) --> 'Null 'PGbool

227−upperInf = unsafeFunction "upper_inf"

228−

229−rangeMerge :: '[null ('PGrange ty), null ('PGrange ty)] ---> null ('PGrange ty)

230−rangeMerge = unsafeFunctionN "range_merge"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Set.hsdeleted−139

@@ -1,139 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Set

3−Description: Set returning functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Set returning functions

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DataKinds

14− , FlexibleContexts

15− , OverloadedStrings

16− , PolyKinds

17− , RankNTypes

18− , ScopedTypeVariables

19− , TypeApplications

20− , TypeOperators

21−#-}

22−

23−module Squeal.PostgreSQL.Expression.Set

24− ( generateSeries

25− , generateSeriesStep

26− , generateSeriesTimestamp

27− , SetFunction

28− , unsafeSetFunction

29− , SetFunctionDB

30− , setFunction

31− , SetFunctionN

32− , unsafeSetFunctionN

33− , SetFunctionNDB

34− , setFunctionN

35− ) where

36−

37−import GHC.TypeLits

38−

39−import qualified Generics.SOP as SOP

40−

41−import Squeal.PostgreSQL.Alias

42−import Squeal.PostgreSQL.Expression

43−import Squeal.PostgreSQL.List

44−import Squeal.PostgreSQL.Render

45−import Squeal.PostgreSQL.Query

46−import Squeal.PostgreSQL.Schema

47−

48−{- |

49−A @RankNType@ for set returning functions with 1 argument.

50−-}

51−type SetFunction fun ty row

52− = forall outer commons schemas params

53− . Expression outer commons 'Ungrouped schemas params '[] ty

54− -- ^ input

55− -> FromClause outer commons schemas params '[fun ::: row]

56− -- ^ output

57−

58−type SetFunctionDB fun schemas ty row

59− = forall outer commons params

60− . Expression outer commons 'Ungrouped schemas params '[] ty

61− -- ^ input

62− -> FromClause outer commons schemas params '[fun ::: row]

63− -- ^ output

64−

65−-- | Escape hatch for a set returning function with 1 argument.

66−unsafeSetFunction

67− :: forall fun ty row. KnownSymbol fun

68− => SetFunction fun ty row -- ^ set returning function

69−unsafeSetFunction x = UnsafeFromClause $

70− renderSymbol @fun <> parenthesized (renderSQL x)

71−

72−setFunction

73− :: ( Has sch schemas schema

74− , Has fun schema ('Function ('[ty] :=> 'ReturnsTable row)) )

75− => QualifiedAlias sch fun

76− -> SetFunctionDB fun schemas ty row

77−setFunction _ = unsafeSetFunction

78−

79−{- |

80−A @RankNType@ for set returning functions with multiple argument.

81−-}

82−type SetFunctionN fun tys row

83− = forall outer commons schemas params

84− . NP (Expression outer commons 'Ungrouped schemas params '[]) tys

85− -- ^ inputs

86− -> FromClause outer commons schemas params '[fun ::: row]

87− -- ^ output

88−

89−-- | Escape hatch for a set returning function with multiple argument.

90−unsafeSetFunctionN

91− :: forall fun tys row. (SOP.SListI tys, KnownSymbol fun)

92− => SetFunctionN fun tys row -- ^ set returning function

93−unsafeSetFunctionN xs = UnsafeFromClause $

94− renderSymbol @fun <> parenthesized (renderCommaSeparated renderSQL xs)

95−

96−type SetFunctionNDB fun schemas tys row

97− = forall outer commons params

98− . NP (Expression outer commons 'Ungrouped schemas params '[]) tys

99− -- ^ inputs

100− -> FromClause outer commons schemas params '[fun ::: row]

101− -- ^ output

102−

103−setFunctionN

104− :: ( Has sch schemas schema

105− , Has fun schema ('Function (tys :=> 'ReturnsTable row))

106− , SOP.SListI tys )

107− => QualifiedAlias sch fun

108− -> SetFunctionNDB fun schemas tys row

109−setFunctionN _ = unsafeSetFunctionN

110−

111−{- | @generateSeries (start *: stop)@

112−

113−Generate a series of values, from @start@ to @stop@ with a step size of one

114−-}

115−generateSeries

116− :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

117− => SetFunctionN "generate_series" '[ null ty, null ty]

118− '["generate_series" ::: null ty] -- ^ set returning function

119−generateSeries = unsafeSetFunctionN

120−

121−{- | @generateSeries (start :* stop *: step)@

122−

123−Generate a series of values, from @start@ to @stop@ with a step size of @step@

124−-}

125−generateSeriesStep

126− :: ty `In` '[ 'PGint4, 'PGint8, 'PGnumeric]

127− => SetFunctionN "generate_series" '[null ty, null ty, null ty]

128− '["generate_series" ::: null ty] -- ^ set returning function

129−generateSeriesStep = unsafeSetFunctionN

130−

131−{- | @generateSeries (start :* stop *: step)@

132−

133−Generate a series of values, from @start@ to @stop@ with a step size of @step@

134−-}

135−generateSeriesTimestamp

136− :: ty `In` '[ 'PGtimestamp, 'PGtimestamptz]

137− => SetFunctionN "generate_series" '[null ty, null ty, null 'PGinterval]

138− '["generate_series" ::: null ty] -- ^ set returning function

139−generateSeriesTimestamp = unsafeSetFunctionN

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Sort.hsdeleted−85

@@ -1,85 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Sort

3−Description: Sort expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Sort expressions

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , GADTs

14− , LambdaCase

15− , OverloadedStrings

16− , StandaloneDeriving

17−#-}

18−

19−module Squeal.PostgreSQL.Expression.Sort

20− ( SortExpression (..)

21− , OrderBy (..)

22− ) where

23−

24−import Squeal.PostgreSQL.Expression

25−import Squeal.PostgreSQL.Render

26−import Squeal.PostgreSQL.Schema

27−

28−-- | `SortExpression`s are used by `orderBy` to optionally sort the results

29−-- of a `Squeal.PostgreSQL.Query.Query`. `Asc` or `Desc`

30−-- set the sort direction of a `NotNull` result

31−-- column to ascending or descending. Ascending order puts smaller values

32−-- first, where "smaller" is defined in terms of the

33−-- `Squeal.PostgreSQL.Expression.Comparison..<` operator. Similarly,

34−-- descending order is determined with the

35−-- `Squeal.PostgreSQL.Expression.Comparison..>` operator. `AscNullsFirst`,

36−-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to

37−-- determine whether nulls appear before or after non-null values in the sort

38−-- ordering of a `Null` result column.

39−data SortExpression outer commons grp schemas params from where

40− Asc

41− :: Expression outer commons grp schemas params from ('NotNull ty)

42− -> SortExpression outer commons grp schemas params from

43− Desc

44− :: Expression outer commons grp schemas params from ('NotNull ty)

45− -> SortExpression outer commons grp schemas params from

46− AscNullsFirst

47− :: Expression outer commons grp schemas params from ('Null ty)

48− -> SortExpression outer commons grp schemas params from

49− AscNullsLast

50− :: Expression outer commons grp schemas params from ('Null ty)

51− -> SortExpression outer commons grp schemas params from

52− DescNullsFirst

53− :: Expression outer commons grp schemas params from ('Null ty)

54− -> SortExpression outer commons grp schemas params from

55− DescNullsLast

56− :: Expression outer commons grp schemas params from ('Null ty)

57− -> SortExpression outer commons grp schemas params from

58−deriving instance Show (SortExpression outer commons grp schemas params from)

59−instance RenderSQL (SortExpression outer commons grp schemas params from) where

60− renderSQL = \case

61− Asc expression -> renderSQL expression <+> "ASC"

62− Desc expression -> renderSQL expression <+> "DESC"

63− AscNullsFirst expression -> renderSQL expression

64− <+> "ASC NULLS FIRST"

65− DescNullsFirst expression -> renderSQL expression

66− <+> "DESC NULLS FIRST"

67− AscNullsLast expression -> renderSQL expression <+> "ASC NULLS LAST"

68− DescNullsLast expression -> renderSQL expression <+> "DESC NULLS LAST"

69−

70−{- |

71−The `orderBy` clause causes the result rows of a `Squeal.PostgreSQL.Query.TableExpression`

72−to be sorted according to the specified `SortExpression`(s).

73−If two rows are equal according to the leftmost expression,

74−they are compared according to the next expression and so on.

75−If they are equal according to all specified expressions,

76−they are returned in an implementation-dependent order.

77−

78−You can also control the order in which rows are processed by window functions

79−using `orderBy` within `Squeal.PostgreSQL.Query.Over`.

80−-}

81−class OrderBy expr where

82− orderBy

83− :: [SortExpression outer commons grp schemas params from]

84− -> expr outer commons grp schemas params from

85− -> expr outer commons grp schemas params from

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Subquery.hsdeleted−120

@@ -1,120 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Subquery

3−Description: Subquery expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Subquery expressions

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , RankNTypes

15− , TypeOperators

16−#-}

17−

18−module Squeal.PostgreSQL.Expression.Subquery

19− ( exists

20− , in_

21− , notIn

22− , subAll

23− , subAny

24− ) where

25−

26−import Squeal.PostgreSQL.Alias

27−import Squeal.PostgreSQL.Expression

28−import Squeal.PostgreSQL.Expression.Logic

29−import Squeal.PostgreSQL.List

30−import Squeal.PostgreSQL.Query

31−import Squeal.PostgreSQL.Render

32−import Squeal.PostgreSQL.Schema

33−

34−-- $setup

35−-- >>> import Squeal.PostgreSQL

36−

37−{- |

38−The argument of `exists` is an arbitrary subquery. The subquery is evaluated

39−to determine whether it returns any rows. If it returns at least one row,

40−the result of `exists` is `true`; if the subquery returns no rows,

41−the result of `exists` is `false`.

42−

43−The subquery can refer to variables from the surrounding query,

44−which will act as constants during any one evaluation of the subquery.

45−

46−The subquery will generally only be executed long enough to determine whether

47−at least one row is returned, not all the way to completion.

48−-}

49−exists

50− :: Query (Join outer from) commons schemas params row

51− -> Condition outer commons grp schemas params from

52−exists query = UnsafeExpression $ "EXISTS" <+> parenthesized (renderSQL query)

53−

54−{- |

55−The right-hand side is a parenthesized subquery, which must return

56−exactly one column. The left-hand expression is evaluated and compared to each

57−row of the subquery result using the given `Operator`,

58−which must yield a Boolean result. The result of `subAll` is `true`

59−if all rows yield true (including the case where the subquery returns no rows).

60−The result is `false` if any `false` result is found.

61−The result is `Squeal.PostgreSQL.Expression.Null.null_` if

62− no comparison with a subquery row returns `false`,

63−and at least one comparison returns `Squeal.PostgreSQL.Expression.Null.null_`.

64−

65−>>> printSQL $ subAll true (.==) (values_ (true `as` #foo))

66−(TRUE = ALL (SELECT * FROM (VALUES (TRUE)) AS t ("foo")))

67−-}

68−subAll

69− :: Expression outer commons grp schemas params from ty1 -- ^ expression

70− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator

71− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery

72− -> Condition outer commons grp schemas params from

73−subAll expr (?) qry = expr ?

74− (UnsafeExpression $ "ALL" <+> parenthesized (renderSQL qry))

75−

76−{- |

77−The right-hand side is a parenthesized subquery, which must return exactly one column.

78−The left-hand expression is evaluated and compared to each row of the subquery result

79−using the given `Operator`, which must yield a Boolean result. The result of `subAny` is `true`

80−if any `true` result is obtained. The result is `false` if no true result is found

81−(including the case where the subquery returns no rows).

82−

83−>>> printSQL $ subAny "foo" like (values_ ("foobar" `as` #foo))

84−(E'foo' LIKE ANY (SELECT * FROM (VALUES (E'foobar')) AS t ("foo")))

85−-}

86−subAny

87− :: Expression outer commons grp schemas params from ty1 -- ^ expression

88− -> Operator ty1 ty2 ('Null 'PGbool) -- ^ operator

89− -> Query (Join outer from) commons schemas params '[col ::: ty2] -- ^ subquery

90− -> Condition outer commons grp schemas params from

91−subAny expr (?) qry = expr ?

92− (UnsafeExpression $ "ANY" <+> parenthesized (renderSQL qry))

93−

94−{- |

95−The result is `true` if the left-hand expression's result is equal

96−to any of the right-hand expressions.

97−

98−>>> printSQL $ true `in_` [true, false, null_]

99−TRUE IN (TRUE, FALSE, NULL)

100−-}

101−in_

102− :: Expression outer commons grp schemas params from ty -- ^ expression

103− -> [Expression outer commons grp schemas params from ty]

104− -> Condition outer commons grp schemas params from

105−expr `in_` exprs = UnsafeExpression $ renderSQL expr <+> "IN"

106− <+> parenthesized (commaSeparated (renderSQL <$> exprs))

107−

108−{- |

109−The result is `true` if the left-hand expression's result is not equal

110−to any of the right-hand expressions.

111−

112−>>> printSQL $ true `notIn` [false, null_]

113−TRUE NOT IN (FALSE, NULL)

114−-}

115−notIn

116− :: Expression outer commons grp schemas params from ty -- ^ expression

117− -> [Expression outer commons grp schemas params from ty]

118− -> Condition outer commons grp schemas params from

119−expr `notIn` exprs = UnsafeExpression $ renderSQL expr <+> "NOT IN"

120− <+> parenthesized (commaSeparated (renderSQL <$> exprs))

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Text.hsdeleted−64

@@ -1,64 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Text

3−Description: Text expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−String functions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , TypeOperators

15−#-}

16−

17−module Squeal.PostgreSQL.Expression.Text

18− ( lower

19− , upper

20− , charLength

21− , like

22− , ilike

23− ) where

24−

25−import Squeal.PostgreSQL.Expression

26−import Squeal.PostgreSQL.Schema

27−

28−-- $setup

29−-- >>> import Squeal.PostgreSQL

30−

31−-- | >>> printSQL $ lower "ARRRGGG"

32−-- lower(E'ARRRGGG')

33−lower :: null 'PGtext --> null 'PGtext

34−lower = unsafeFunction "lower"

35−

36−-- | >>> printSQL $ upper "eeee"

37−-- upper(E'eeee')

38−upper :: null 'PGtext --> null 'PGtext

39−upper = unsafeFunction "upper"

40−

41−-- | >>> printSQL $ charLength "four"

42−-- char_length(E'four')

43−charLength :: null 'PGtext --> null 'PGint4

44−charLength = unsafeFunction "char_length"

45−

46−-- | The `like` expression returns true if the @string@ matches

47−-- the supplied @pattern@. If @pattern@ does not contain percent signs

48−-- or underscores, then the pattern only represents the string itself;

49−-- in that case `like` acts like the equals operator. An underscore (_)

50−-- in pattern stands for (matches) any single character; a percent sign (%)

51−-- matches any sequence of zero or more characters.

52−--

53−-- >>> printSQL $ "abc" `like` "a%"

54−-- (E'abc' LIKE E'a%')

55−like :: Operator (null 'PGtext) (null 'PGtext) ('Null 'PGbool)

56−like = unsafeBinaryOp "LIKE"

57−

58−-- | The key word ILIKE can be used instead of LIKE to make the

59−-- match case-insensitive according to the active locale.

60−--

61−-- >>> printSQL $ "abc" `ilike` "a%"

62−-- (E'abc' ILIKE E'a%')

63−ilike :: Operator (null 'PGtext) (null 'PGtext) ('Null 'PGbool)

64−ilike = unsafeBinaryOp "ILIKE"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/TextSearch.hsdeleted−157

@@ -1,157 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.TextSearch

3−Description: Text search expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Text search functions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , OverloadedStrings

14− , TypeOperators

15−#-}

16−

17−module Squeal.PostgreSQL.Expression.TextSearch

18− ( (@@)

19− , (.&)

20− , (.|)

21− , (.!)

22− , (<->)

23− , arrayToTSvector

24− , tsvectorLength

25− , numnode

26− , plainToTSquery

27− , phraseToTSquery

28− , websearchToTSquery

29− , queryTree

30− , toTSquery

31− , toTSvector

32− , setWeight

33− , strip

34− , jsonToTSvector

35− , jsonbToTSvector

36− , tsDelete

37− , tsFilter

38− , tsHeadline

39− ) where

40−

41−import Squeal.PostgreSQL.Expression

42−import Squeal.PostgreSQL.List

43−import Squeal.PostgreSQL.Schema

44−

45−-- | `Squeal.PostgreSQL.Expression.Type.tsvector` matches tsquery ?

46−(@@) :: Operator (null 'PGtsvector) (null 'PGtsquery) ('Null 'PGbool)

47−(@@) = unsafeBinaryOp "@@"

48−

49−-- | AND `Squeal.PostgreSQL.Expression.Type.tsquery`s together

50−(.&) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

51−(.&) = unsafeBinaryOp "&&"

52−

53−-- | OR `Squeal.PostgreSQL.Expression.Type.tsquery`s together

54−(.|) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

55−(.|) = unsafeBinaryOp "||"

56−

57−-- | negate a `Squeal.PostgreSQL.Expression.Type.tsquery`

58−(.!) :: null 'PGtsquery --> null 'PGtsquery

59−(.!) = unsafeLeftOp "!!"

60−

61−-- | `Squeal.PostgreSQL.Expression.Type.tsquery` followed by

62−-- `Squeal.PostgreSQL.Expression.Type.tsquery`

63−(<->) :: Operator (null 'PGtsquery) (null 'PGtsquery) (null 'PGtsquery)

64−(<->) = unsafeBinaryOp "<->"

65−

66−-- | convert array of lexemes to `Squeal.PostgreSQL.Expression.Type.tsvector`

67−arrayToTSvector

68− :: null ('PGvararray ('NotNull 'PGtext))

69− --> null 'PGtsvector

70−arrayToTSvector = unsafeFunction "array_to_tsvector"

71−

72−-- | number of lexemes in `Squeal.PostgreSQL.Expression.Type.tsvector`

73−tsvectorLength :: null 'PGtsvector --> null 'PGint4

74−tsvectorLength = unsafeFunction "length"

75−

76−-- | number of lexemes plus operators in `Squeal.PostgreSQL.Expression.Type.tsquery`

77−numnode :: null 'PGtsquery --> null 'PGint4

78−numnode = unsafeFunction "numnode"

79−

80−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` ignoring punctuation

81−plainToTSquery :: null 'PGtext --> null 'PGtsquery

82−plainToTSquery = unsafeFunction "plainto_tsquery"

83−

84−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` that searches for a phrase,

85−-- ignoring punctuation

86−phraseToTSquery :: null 'PGtext --> null 'PGtsquery

87−phraseToTSquery = unsafeFunction "phraseto_tsquery"

88−

89−-- | produce `Squeal.PostgreSQL.Expression.Type.tsquery` from a web search style query

90−websearchToTSquery :: null 'PGtext --> null 'PGtsquery

91−websearchToTSquery = unsafeFunction "websearch_to_tsquery"

92−

93−-- | get indexable part of a `Squeal.PostgreSQL.Expression.Type.tsquery`

94−queryTree :: null 'PGtsquery --> null 'PGtext

95−queryTree = unsafeFunction "query_tree"

96−

97−-- | normalize words and convert to `Squeal.PostgreSQL.Expression.Type.tsquery`

98−toTSquery :: null 'PGtext --> null 'PGtsquery

99−toTSquery = unsafeFunction "to_tsquery"

100−

101−-- | reduce document text to `Squeal.PostgreSQL.Expression.Type.tsvector`

102−toTSvector

103− :: ty `In` '[ 'PGtext, 'PGjson, 'PGjsonb]

104− => null ty --> null 'PGtsvector

105−toTSvector = unsafeFunction "to_tsvector"

106−

107−-- | assign weight to each element of `Squeal.PostgreSQL.Expression.Type.tsvector`

108−setWeight :: '[null 'PGtsvector, null ('PGchar 1)] ---> null 'PGtsvector

109−setWeight = unsafeFunctionN "set_weight"

110−

111−-- | remove positions and weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

112−strip :: null 'PGtsvector --> null 'PGtsvector

113−strip = unsafeFunction "strip"

114−

115−-- | @jsonToTSvector (document *: filter)@

116−-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

117−-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

118−-- filter is a `Squeal.PostgreSQL.Expression.Type.json` array, that enumerates what kind of elements

119−-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

120−-- Possible values for filter are "string" (to include all string values),

121−-- "numeric" (to include all numeric values in the string format),

122−-- "boolean" (to include all Boolean values in the string format "true"/"false"),

123−-- "key" (to include all keys) or "all" (to include all above).

124−-- These values can be combined together to include, e.g. all string and numeric values.

125−jsonToTSvector :: '[null 'PGjson, null 'PGjson] ---> null 'PGtsvector

126−jsonToTSvector = unsafeFunctionN "json_to_tsvector"

127−

128−-- | @jsonbToTSvector (document *: filter)@

129−-- reduce each value in the document, specified by filter to a `Squeal.PostgreSQL.Expression.Type.tsvector`,

130−-- and then concatenate those in document order to produce a single `Squeal.PostgreSQL.Expression.Type.tsvector`.

131−-- filter is a `Squeal.PostgreSQL.Expression.Type.jsonb` array, that enumerates what kind of elements

132−-- need to be included into the resulting `Squeal.PostgreSQL.Expression.Type.tsvector`.

133−-- Possible values for filter are "string" (to include all string values),

134−-- "numeric" (to include all numeric values in the string format),

135−-- "boolean" (to include all Boolean values in the string format "true"/"false"),

136−-- "key" (to include all keys) or "all" (to include all above).

137−-- These values can be combined together to include, e.g. all string and numeric values.

138−jsonbToTSvector :: '[null 'PGjsonb, null 'PGjsonb] ---> null 'PGtsvector

139−jsonbToTSvector = unsafeFunctionN "jsonb_to_tsvector"

140−

141−-- | remove given lexeme from `Squeal.PostgreSQL.Expression.Type.tsvector`

142−tsDelete ::

143− '[null 'PGtsvector, null ('PGvararray ('NotNull 'PGtext))]

144− ---> null 'PGtsvector

145−tsDelete = unsafeFunctionN "ts_delete"

146−

147−-- | select only elements with given weights from `Squeal.PostgreSQL.Expression.Type.tsvector`

148−tsFilter ::

149− '[null 'PGtsvector, null ('PGvararray ('NotNull ('PGchar 1)))]

150− ---> null 'PGtsvector

151−tsFilter = unsafeFunctionN "ts_filter"

152−

153−-- | display a `Squeal.PostgreSQL.Expression.Type.tsquery` match

154−tsHeadline

155− :: document `In` '[ 'PGtext, 'PGjson, 'PGjsonb]

156− => '[null document, null 'PGtsquery] ---> null 'PGtext

157−tsHeadline = unsafeFunctionN "ts_headline"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Time.hsdeleted−192

@@ -1,192 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Time

3−Description: Date/Time expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Date/Time functions and operators

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , DeriveGeneric

14− , FunctionalDependencies

15− , LambdaCase

16− , MultiParamTypeClasses

17− , OverloadedStrings

18− , PolyKinds

19− , RankNTypes

20− , TypeOperators

21−#-}

22−

23−module Squeal.PostgreSQL.Expression.Time

24− ( TimeOp (..)

25− , currentDate

26− , currentTime

27− , currentTimestamp

28− , localTime

29− , localTimestamp

30− , now

31− , makeDate

32− , makeTime

33− , makeTimestamp

34− , makeTimestamptz

35− , interval_

36− , TimeUnit (..)

37− ) where

38−

39−import Data.String

40−

41−import qualified GHC.Generics as GHC

42−import qualified Generics.SOP as SOP

43−

44−import Squeal.PostgreSQL.Expression

45−import Squeal.PostgreSQL.Render

46−import Squeal.PostgreSQL.Schema

47−

48−-- $setup

49−-- >>> import Squeal.PostgreSQL

50−

51−-- | >>> printSQL currentDate

52−-- CURRENT_DATE

53−currentDate :: Expr (null 'PGdate)

54−currentDate = UnsafeExpression "CURRENT_DATE"

55−

56−-- | >>> printSQL currentTime

57−-- CURRENT_TIME

58−currentTime :: Expr (null 'PGtimetz)

59−currentTime = UnsafeExpression "CURRENT_TIME"

60−

61−-- | >>> printSQL currentTimestamp

62−-- CURRENT_TIMESTAMP

63−currentTimestamp :: Expr (null 'PGtimestamptz)

64−currentTimestamp = UnsafeExpression "CURRENT_TIMESTAMP"

65−

66−-- | >>> printSQL localTime

67−-- LOCALTIME

68−localTime :: Expr (null 'PGtime)

69−localTime = UnsafeExpression "LOCALTIME"

70−

71−-- | >>> printSQL localTimestamp

72−-- LOCALTIMESTAMP

73−localTimestamp :: Expr (null 'PGtimestamp)

74−localTimestamp = UnsafeExpression "LOCALTIMESTAMP"

75−

76−-- | Current date and time (equivalent to `currentTimestamp`)

77−--

78−-- >>> printSQL now

79−-- now()

80−now :: Expr (null 'PGtimestamptz)

81−now = UnsafeExpression "now()"

82−

83−{-|

84−Create date from year, month and day fields

85−

86−>>> printSQL (makeDate (1984 :* 7 *: 3))

87−make_date(1984, 7, 3)

88−-}

89−makeDate :: '[ null 'PGint4, null 'PGint4, null 'PGint4 ] ---> null 'PGdate

90−makeDate = unsafeFunctionN "make_date"

91−

92−{-|

93−Create time from hour, minute and seconds fields

94−

95−>>> printSQL (makeTime (8 :* 15 *: 23.5))

96−make_time(8, 15, 23.5)

97−-}

98−makeTime :: '[ null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtime

99−makeTime = unsafeFunctionN "make_time"

100−

101−{-|

102−Create timestamp from year, month, day, hour, minute and seconds fields

103−

104−>>> printSQL (makeTimestamp (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

105−make_timestamp(2013, 7, 15, 8, 15, 23.5)

106−-}

107−makeTimestamp ::

108− '[ null 'PGint4, null 'PGint4, null 'PGint4

109− , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamp

110−makeTimestamp = unsafeFunctionN "make_timestamp"

111−

112−{-|

113−Create timestamp with time zone from

114−year, month, day, hour, minute and seconds fields;

115−the current time zone is used

116−

117−>>> printSQL (makeTimestamptz (2013 :* 7 :* 15 :* 8 :* 15 *: 23.5))

118−make_timestamptz(2013, 7, 15, 8, 15, 23.5)

119−-}

120−makeTimestamptz ::

121− '[ null 'PGint4, null 'PGint4, null 'PGint4

122− , null 'PGint4, null 'PGint4, null 'PGfloat8 ] ---> null 'PGtimestamptz

123−makeTimestamptz = unsafeFunctionN "make_timestamptz"

124−

125−{-|

126−Affine space operations on time types.

127−-}

128−class TimeOp time diff | time -> diff where

129− {-|

130− >>> printSQL (makeDate (1984 :* 7 *: 3) !+ 365)

131− (make_date(1984, 7, 3) + 365)

132− -}

133− (!+) :: Operator (null time) (null diff) (null time)

134− (!+) = unsafeBinaryOp "+"

135− {-|

136− >>> printSQL (365 +! makeDate (1984 :* 7 *: 3))

137− (365 + make_date(1984, 7, 3))

138− -}

139− (+!) :: Operator (null diff) (null time) (null time)

140− (+!) = unsafeBinaryOp "+"

141− {-|

142− >>> printSQL (makeDate (1984 :* 7 *: 3) !- 365)

143− (make_date(1984, 7, 3) - 365)

144− -}

145− (!-) :: Operator (null time) (null diff) (null time)

146− (!-) = unsafeBinaryOp "-"

147− {-|

148− >>> printSQL (makeDate (1984 :* 7 *: 3) !-! currentDate)

149− (make_date(1984, 7, 3) - CURRENT_DATE)

150− -}

151− (!-!) :: Operator (null time) (null time) (null diff)

152− (!-!) = unsafeBinaryOp "-"

153−instance TimeOp 'PGtimestamp 'PGinterval

154−instance TimeOp 'PGtimestamptz 'PGinterval

155−instance TimeOp 'PGtime 'PGinterval

156−instance TimeOp 'PGtimetz 'PGinterval

157−instance TimeOp 'PGinterval 'PGinterval

158−instance TimeOp 'PGdate 'PGint4

159−infixl 6 !+

160−infixl 6 +!

161−infixl 6 !-

162−infixl 6 !-!

163−

164−-- | A `TimeUnit` to use in `interval_` construction.

165−data TimeUnit

166− = Years | Months | Weeks | Days

167− | Hours | Minutes | Seconds

168− | Microseconds | Milliseconds

169− | Decades | Centuries | Millennia

170− deriving (Eq, Ord, Show, Read, Enum, GHC.Generic)

171−instance SOP.Generic TimeUnit

172−instance SOP.HasDatatypeInfo TimeUnit

173−instance RenderSQL TimeUnit where

174− renderSQL = \case

175− Years -> "years"

176− Months -> "months"

177− Weeks -> "weeks"

178− Days -> "days"

179− Hours -> "hours"

180− Minutes -> "minutes"

181− Seconds -> "seconds"

182− Microseconds -> "microseconds"

183− Milliseconds -> "milliseconds"

184− Decades -> "decades"

185− Centuries -> "centuries"

186− Millennia -> "millennia"

187−

188−-- | >>> printSQL $ interval_ 7 Days

189−-- (INTERVAL '7.0 days')

190−interval_ :: Double -> TimeUnit -> Expr (null 'PGinterval)

191−interval_ num unit = UnsafeExpression . parenthesized $ "INTERVAL" <+>

192− "'" <> fromString (show num) <+> renderSQL unit <> "'"

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Type.hsdeleted−446

@@ -1,446 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression

3−Description: Type expressions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Type expressions.

9−-}

10−

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DataKinds

14− , DeriveGeneric

15− , FlexibleContexts

16− , FlexibleInstances

17− , GADTs

18− , GeneralizedNewtypeDeriving

19− , KindSignatures

20− , MultiParamTypeClasses

21− , OverloadedStrings

22− , RankNTypes

23− , ScopedTypeVariables

24− , TypeApplications

25− , TypeOperators

26− , UndecidableInstances

27−#-}

28−

29−module Squeal.PostgreSQL.Expression.Type

30− ( -- * type casting

31− cast

32− , astype

33− , inferredtype

34− -- * type expressions

35− , TypeExpression (..)

36− , typedef

37− , typetable

38− , typeview

39− , bool

40− , int2

41− , smallint

42− , int4

43− , int

44− , integer

45− , int8

46− , bigint

47− , numeric

48− , float4

49− , real

50− , float8

51− , doublePrecision

52− , money

53− , text

54− , char

55− , character

56− , varchar

57− , characterVarying

58− , bytea

59− , timestamp

60− , timestampWithTimeZone

61− , timestamptz

62− , date

63− , time

64− , timeWithTimeZone

65− , timetz

66− , interval

67− , uuid

68− , inet

69− , json

70− , jsonb

71− , vararray

72− , fixarray

73− , tsvector

74− , tsquery

75− , oid

76− , int4range

77− , int8range

78− , numrange

79− , tsrange

80− , tstzrange

81− , daterange

82− -- * column type definitions

83− , ColumnTypeExpression (..)

84− , nullable

85− , notNullable

86− , default_

87− , serial2

88− , smallserial

89− , serial4

90− , serial

91− , serial8

92− , bigserial

93− , hask

94− -- * type inference

95− , PGTyped (..)

96− , PGNullityTyped (..)

97− , FieldTyped (..)

98− ) where

99−

100−import Control.DeepSeq

101−import Data.ByteString

102−import Data.String

103−import GHC.TypeLits

104−

105−import qualified Data.ByteString as ByteString

106−import qualified GHC.Generics as GHC

107−import qualified Generics.SOP as SOP

108−

109−import Squeal.PostgreSQL.Alias

110−import Squeal.PostgreSQL.Expression

111−import Squeal.PostgreSQL.PG

112−import Squeal.PostgreSQL.Render

113−import Squeal.PostgreSQL.Schema

114−

115−-- $setup

116−-- >>> import Squeal.PostgreSQL

117−

118−-- When a `cast` is applied to an `Expression` of a known type, it

119−-- represents a run-time type conversion. The cast will succeed only if a

120−-- suitable type conversion operation has been defined.

121−--

122−-- | >>> printSQL $ true & cast int4

123−-- (TRUE :: int4)

124−cast

125− :: TypeExpression schemas ty1

126− -- ^ type to cast as

127− -> Expression outer commons grp schemas params from ty0

128− -- ^ value to convert

129− -> Expression outer commons grp schemas params from ty1

130−cast ty x = UnsafeExpression $ parenthesized $

131− renderSQL x <+> "::" <+> renderSQL ty

132−

133−-- | A safe version of `cast` which just matches a value with its type.

134−--

135−-- >>> printSQL (1 & astype int)

136−-- (1 :: int)

137−astype

138− :: TypeExpression schemas ty

139− -- ^ type to specify as

140− -> Expression outer commons grp schemas params from ty

141− -- ^ value

142− -> Expression outer commons grp schemas params from ty

143−astype = cast

144−

145−-- | `inferredtype` will add a type annotation to an `Expression`

146−-- which can be useful for fixing the storage type of a value.

147−--

148−-- >>> printSQL (inferredtype true)

149−-- (TRUE :: bool)

150−inferredtype

151− :: PGTyped schemas ty

152− => Expression outer common grp schemas params from ty

153− -- ^ value

154− -> Expression outer common grp schemas params from ty

155−inferredtype = astype pgtype

156−

157−{-----------------------------------------

158−type expressions

159−-----------------------------------------}

160−

161−-- | `TypeExpression`s are used in `cast`s and

162−-- `Squeal.PostgreSQL.Definition.createTable` commands.

163−newtype TypeExpression (schemas :: SchemasType) (ty :: NullityType)

164− = UnsafeTypeExpression { renderTypeExpression :: ByteString }

165− deriving (GHC.Generic,Show,Eq,Ord,NFData)

166−instance RenderSQL (TypeExpression schemas ty) where

167− renderSQL = renderTypeExpression

168−

169−-- | The enum or composite type in a `Typedef` can be expressed by its alias.

170−typedef

171− :: (Has sch schemas schema, Has td schema ('Typedef ty))

172− => QualifiedAlias sch td

173− -- ^ type alias

174− -> TypeExpression schemas (null ty)

175−typedef = UnsafeTypeExpression . renderSQL

176−

177−-- | The composite type corresponding to a `Table` definition can be expressed

178−-- by its alias.

179−typetable

180− :: (Has sch schemas schema, Has tab schema ('Table table))

181− => QualifiedAlias sch tab

182− -- ^ table alias

183− -> TypeExpression schemas (null ('PGcomposite (TableToRow table)))

184−typetable = UnsafeTypeExpression . renderSQL

185−

186−-- | The composite type corresponding to a `View` definition can be expressed

187−-- by its alias.

188−typeview

189− :: (Has sch schemas schema, Has vw schema ('View view))

190− => QualifiedAlias sch vw

191− -- ^ view alias

192− -> TypeExpression schemas (null ('PGcomposite view))

193−typeview = UnsafeTypeExpression . renderSQL

194−

195−-- | logical Boolean (true/false)

196−bool :: TypeExpression schemas (null 'PGbool)

197−bool = UnsafeTypeExpression "bool"

198−-- | signed two-byte integer

199−int2, smallint :: TypeExpression schemas (null 'PGint2)

200−int2 = UnsafeTypeExpression "int2"

201−smallint = UnsafeTypeExpression "smallint"

202−-- | signed four-byte integer

203−int4, int, integer :: TypeExpression schemas (null 'PGint4)

204−int4 = UnsafeTypeExpression "int4"

205−int = UnsafeTypeExpression "int"

206−integer = UnsafeTypeExpression "integer"

207−-- | signed eight-byte integer

208−int8, bigint :: TypeExpression schemas (null 'PGint8)

209−int8 = UnsafeTypeExpression "int8"

210−bigint = UnsafeTypeExpression "bigint"

211−-- | arbitrary precision numeric type

212−numeric :: TypeExpression schemas (null 'PGnumeric)

213−numeric = UnsafeTypeExpression "numeric"

214−-- | single precision floating-point number (4 bytes)

215−float4, real :: TypeExpression schemas (null 'PGfloat4)

216−float4 = UnsafeTypeExpression "float4"

217−real = UnsafeTypeExpression "real"

218−-- | double precision floating-point number (8 bytes)

219−float8, doublePrecision :: TypeExpression schemas (null 'PGfloat8)

220−float8 = UnsafeTypeExpression "float8"

221−doublePrecision = UnsafeTypeExpression "double precision"

222−-- | currency amount

223−money :: TypeExpression schema (null 'PGmoney)

224−money = UnsafeTypeExpression "money"

225−-- | variable-length character string

226−text :: TypeExpression schemas (null 'PGtext)

227−text = UnsafeTypeExpression "text"

228−-- | fixed-length character string

229−char, character

230− :: forall n schemas null. (KnownNat n, 1 <= n)

231− => TypeExpression schemas (null ('PGchar n))

232−char = UnsafeTypeExpression $ "char(" <> renderNat @n <> ")"

233−character = UnsafeTypeExpression $ "character(" <> renderNat @n <> ")"

234−-- | variable-length character string

235−varchar, characterVarying

236− :: forall n schemas null. (KnownNat n, 1 <= n)

237− => TypeExpression schemas (null ('PGvarchar n))

238−varchar = UnsafeTypeExpression $ "varchar(" <> renderNat @n <> ")"

239−characterVarying = UnsafeTypeExpression $

240− "character varying(" <> renderNat @n <> ")"

241−-- | binary data ("byte array")

242−bytea :: TypeExpression schemas (null 'PGbytea)

243−bytea = UnsafeTypeExpression "bytea"

244−-- | date and time (no time zone)

245−timestamp :: TypeExpression schemas (null 'PGtimestamp)

246−timestamp = UnsafeTypeExpression "timestamp"

247−-- | date and time, including time zone

248−timestampWithTimeZone, timestamptz :: TypeExpression schemas (null 'PGtimestamptz)

249−timestampWithTimeZone = UnsafeTypeExpression "timestamp with time zone"

250−timestamptz = UnsafeTypeExpression "timestamptz"

251−-- | calendar date (year, month, day)

252−date :: TypeExpression schemas (null 'PGdate)

253−date = UnsafeTypeExpression "date"

254−-- | time of day (no time zone)

255−time :: TypeExpression schemas (null 'PGtime)

256−time = UnsafeTypeExpression "time"

257−-- | time of day, including time zone

258−timeWithTimeZone, timetz :: TypeExpression schemas (null 'PGtimetz)

259−timeWithTimeZone = UnsafeTypeExpression "time with time zone"

260−timetz = UnsafeTypeExpression "timetz"

261−-- | time span

262−interval :: TypeExpression schemas (null 'PGinterval)

263−interval = UnsafeTypeExpression "interval"

264−-- | universally unique identifier

265−uuid :: TypeExpression schemas (null 'PGuuid)

266−uuid = UnsafeTypeExpression "uuid"

267−-- | IPv4 or IPv6 host address

268−inet :: TypeExpression schemas (null 'PGinet)

269−inet = UnsafeTypeExpression "inet"

270−-- | textual JSON data

271−json :: TypeExpression schemas (null 'PGjson)

272−json = UnsafeTypeExpression "json"

273−-- | binary JSON data, decomposed

274−jsonb :: TypeExpression schemas (null 'PGjsonb)

275−jsonb = UnsafeTypeExpression "jsonb"

276−-- | variable length array

277−vararray

278− :: TypeExpression schemas pg

279− -> TypeExpression schemas (null ('PGvararray pg))

280−vararray ty = UnsafeTypeExpression $ renderSQL ty <> "[]"

281−-- | fixed length array

282−--

283−-- >>> renderSQL (fixarray @'[2] json)

284−-- "json[2]"

285−fixarray

286− :: forall dims schemas null pg. SOP.All KnownNat dims

287− => TypeExpression schemas pg

288− -> TypeExpression schemas (null ('PGfixarray dims pg))

289−fixarray ty = UnsafeTypeExpression $

290− renderSQL ty <> renderDims @dims

291− where

292− renderDims :: forall ns. SOP.All KnownNat ns => ByteString

293− renderDims =

294− ("[" <>)

295− . (<> "]")

296− . ByteString.intercalate "]["

297− . SOP.hcollapse

298− $ SOP.hcmap (SOP.Proxy @KnownNat)

299− (K . fromString . show . natVal)

300− (SOP.hpure SOP.Proxy :: SOP.NP SOP.Proxy ns)

301−-- | text search query

302−tsvector :: TypeExpression schemas (null 'PGtsvector)

303−tsvector = UnsafeTypeExpression "tsvector"

304−-- | text search document

305−tsquery :: TypeExpression schemas (null 'PGtsquery)

306−tsquery = UnsafeTypeExpression "tsquery"

307−-- | Object identifiers (OIDs) are used internally by PostgreSQL

308−-- as primary keys for various system tables.

309−oid :: TypeExpression schemas (null 'PGoid)

310−oid = UnsafeTypeExpression "oid"

311−-- | Range of integer

312−int4range :: TypeExpression schemas (null ('PGrange 'PGint4))

313−int4range = UnsafeTypeExpression "int4range"

314−-- | Range of bigint

315−int8range :: TypeExpression schemas (null ('PGrange 'PGint8))

316−int8range = UnsafeTypeExpression "int8range"

317−-- | Range of numeric

318−numrange :: TypeExpression schemas (null ('PGrange 'PGnumeric))

319−numrange = UnsafeTypeExpression "numrange"

320−-- | Range of timestamp without time zone

321−tsrange :: TypeExpression schemas (null ('PGrange 'PGtimestamp))

322−tsrange = UnsafeTypeExpression "tsrange"

323−-- | Range of timestamp with time zone

324−tstzrange :: TypeExpression schemas (null ('PGrange 'PGtimestamptz))

325−tstzrange = UnsafeTypeExpression "tstzrange"

326−-- | Range of date

327−daterange :: TypeExpression schemas (null ('PGrange 'PGdate))

328−daterange = UnsafeTypeExpression "daterange"

329−

330−-- | `pgtype` is a demoted version of a `PGType`

331−class PGTyped schemas (ty :: NullityType) where

332− pgtype :: TypeExpression schemas ty

333−instance PGTyped schemas (null 'PGbool) where pgtype = bool

334−instance PGTyped schemas (null 'PGint2) where pgtype = int2

335−instance PGTyped schemas (null 'PGint4) where pgtype = int4

336−instance PGTyped schemas (null 'PGint8) where pgtype = int8

337−instance PGTyped schemas (null 'PGnumeric) where pgtype = numeric

338−instance PGTyped schemas (null 'PGfloat4) where pgtype = float4

339−instance PGTyped schemas (null 'PGfloat8) where pgtype = float8

340−instance PGTyped schemas (null 'PGmoney) where pgtype = money

341−instance PGTyped schemas (null 'PGtext) where pgtype = text

342−instance (KnownNat n, 1 <= n)

343− => PGTyped schemas (null ('PGchar n)) where pgtype = char @n

344−instance (KnownNat n, 1 <= n)

345− => PGTyped schemas (null ('PGvarchar n)) where pgtype = varchar @n

346−instance PGTyped schemas (null 'PGbytea) where pgtype = bytea

347−instance PGTyped schemas (null 'PGtimestamp) where pgtype = timestamp

348−instance PGTyped schemas (null 'PGtimestamptz) where pgtype = timestampWithTimeZone

349−instance PGTyped schemas (null 'PGdate) where pgtype = date

350−instance PGTyped schemas (null 'PGtime) where pgtype = time

351−instance PGTyped schemas (null 'PGtimetz) where pgtype = timeWithTimeZone

352−instance PGTyped schemas (null 'PGinterval) where pgtype = interval

353−instance PGTyped schemas (null 'PGuuid) where pgtype = uuid

354−instance PGTyped schemas (null 'PGjson) where pgtype = json

355−instance PGTyped schemas (null 'PGjsonb) where pgtype = jsonb

356−instance PGTyped schemas ty

357− => PGTyped schemas (null ('PGvararray ty)) where

358− pgtype = vararray (pgtype @schemas @ty)

359−instance (SOP.All KnownNat dims, PGTyped schemas ty)

360− => PGTyped schemas (null ('PGfixarray dims ty)) where

361− pgtype = fixarray @dims (pgtype @schemas @ty)

362−instance PGTyped schemas (null 'PGtsvector) where pgtype = tsvector

363−instance PGTyped schemas (null 'PGtsquery) where pgtype = tsquery

364−instance PGTyped schemas (null 'PGoid) where pgtype = oid

365−instance PGTyped schemas (null ('PGrange 'PGint4)) where pgtype = int4range

366−instance PGTyped schemas (null ('PGrange 'PGint8)) where pgtype = int8range

367−instance PGTyped schemas (null ('PGrange 'PGnumeric)) where pgtype = numrange

368−instance PGTyped schemas (null ('PGrange 'PGtimestamp)) where pgtype = tsrange

369−instance PGTyped schemas (null ('PGrange 'PGtimestamptz)) where pgtype = tstzrange

370−instance PGTyped schemas (null ('PGrange 'PGdate)) where pgtype = daterange

371−

372−-- | Lift `PGTyped` to a field

373−class FieldTyped schemas ty where

374− fieldtype :: Aliased (TypeExpression schemas) ty

375−instance (KnownSymbol alias, PGTyped schemas ty)

376− => FieldTyped schemas (alias ::: ty) where

377− fieldtype = pgtype `As` Alias

378−

379−-- | `ColumnTypeExpression`s are used in `createTable` commands.

380−newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)

381− = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }

382− deriving (GHC.Generic,Show,Eq,Ord,NFData)

383−instance RenderSQL (ColumnTypeExpression schemas ty) where

384− renderSQL = renderColumnTypeExpression

385−

386−-- | used in `createTable` commands as a column constraint to note that

387−-- @NULL@ may be present in a column

388−nullable

389− :: TypeExpression schemas (nullity ty)

390− -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)

391−nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"

392−

393−-- | used in `createTable` commands as a column constraint to ensure

394−-- @NULL@ is not present in a column

395−notNullable

396− :: TypeExpression schemas (nullity ty)

397− -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)

398−notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"

399−

400−-- | used in `createTable` commands as a column constraint to give a default

401−default_

402− :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty

403− -> ColumnTypeExpression schemas ('NoDef :=> ty)

404− -> ColumnTypeExpression schemas ('Def :=> ty)

405−default_ x ty = UnsafeColumnTypeExpression $

406− renderSQL ty <+> "DEFAULT" <+> renderExpression x

407−

408−-- | not a true type, but merely a notational convenience for creating

409−-- unique identifier columns with type `PGint2`

410−serial2, smallserial

411− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)

412−serial2 = UnsafeColumnTypeExpression "serial2"

413−smallserial = UnsafeColumnTypeExpression "smallserial"

414−-- | not a true type, but merely a notational convenience for creating

415−-- unique identifier columns with type `PGint4`

416−serial4, serial

417− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)

418−serial4 = UnsafeColumnTypeExpression "serial4"

419−serial = UnsafeColumnTypeExpression "serial"

420−-- | not a true type, but merely a notational convenience for creating

421−-- unique identifier columns with type `PGint8`

422−serial8, bigserial

423− :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)

424−serial8 = UnsafeColumnTypeExpression "serial8"

425−bigserial = UnsafeColumnTypeExpression "bigserial"

426−

427−-- | Like @PGTyped@ but also accounts for nullity.

428−class PGNullityTyped schemas (nullty :: NullityType) where

429− pgNullityType :: ColumnTypeExpression schemas ('NoDef :=> nullty)

430−

431−instance PGTyped schemas ('Null ty) => PGNullityTyped schemas ('Null ty) where

432− pgNullityType = nullable (pgtype @_ @('Null ty))

433−

434−instance PGTyped schemas ('NotNull ty) => PGNullityTyped schemas ('NotNull ty) where

435− pgNullityType = notNullable (pgtype @_ @('NotNull ty))

436−

437−-- | Allow you to specify pg column types in relation to haskell types.

438−-- >>> printSQL $ hask @(Maybe String)

439−-- text NULL

440−--

441−-- >>> printSQL $ hask @Double

442−-- float8 NOT NULL

443−hask

444− :: forall hask schemas. PGNullityTyped schemas (NullPG hask)

445− => ColumnTypeExpression schemas ('NoDef :=> NullPG hask)

446−hask = pgNullityType

squeal-postgresql/src/Squeal/PostgreSQL/Expression/Window.hsdeleted−284

@@ -1,284 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.Expression.Window

3−Description: Window functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Window functions and definitions

9−-}

10−

11−{-# LANGUAGE

12− DataKinds

13− , DeriveGeneric

14− , FlexibleContexts

15− , FlexibleInstances

16− , GADTs

17− , GeneralizedNewtypeDeriving

18− , LambdaCase

19− , MultiParamTypeClasses

20− , OverloadedStrings

21− , RankNTypes

22− , KindSignatures

23−#-}

24−

25−module Squeal.PostgreSQL.Expression.Window

26− ( -- * functions

27− partitionBy

28− , rank

29− , rowNumber

30− , denseRank

31− , percentRank

32− , cumeDist

33− , ntile

34− , lag

35− , lead

36− , firstValue

37− , lastValue

38− , nthValue

39− , unsafeWindowFunction1

40− , unsafeWindowFunctionN

41− -- * types

42− , WindowFunction (..)

43− , WindowDefinition (..)

44− , WinFun0

45− , WinFun1

46− , WinFunN

47− ) where

48−

49−import Control.DeepSeq

50−import Data.ByteString

51−

52−import qualified GHC.Generics as GHC

53−import qualified Generics.SOP as SOP

54−

55−import Squeal.PostgreSQL.Alias

56−import Squeal.PostgreSQL.Expression

57−import Squeal.PostgreSQL.Expression.Aggregate

58−import Squeal.PostgreSQL.Expression.Sort

59−import Squeal.PostgreSQL.List

60−import Squeal.PostgreSQL.Render

61−import Squeal.PostgreSQL.Schema

62−

63−instance Aggregate

64− (Expression outer commons grp schemas params from)

65− (NP (Expression outer commons grp schemas params from))

66− (WindowFunction outer commons grp schemas params from) where

67− countStar = UnsafeWindowFunction "count(*)"

68− count = unsafeWindowFunction1 "count"

69− sum_ = unsafeWindowFunction1 "sum"

70− arrayAgg = unsafeWindowFunction1 "array_agg"

71− jsonAgg = unsafeWindowFunction1 "json_agg"

72− jsonbAgg = unsafeWindowFunction1 "jsonb_agg"

73− bitAnd = unsafeWindowFunction1 "bit_and"

74− bitOr = unsafeWindowFunction1 "bit_or"

75− boolAnd = unsafeWindowFunction1 "bool_and"

76− boolOr = unsafeWindowFunction1 "bool_or"

77− every = unsafeWindowFunction1 "every"

78− max_ = unsafeWindowFunction1 "max"

79− min_ = unsafeWindowFunction1 "min"

80− avg = unsafeWindowFunction1 "avg"

81− corr = unsafeWindowFunctionN "corr"

82− covarPop = unsafeWindowFunctionN "covar_pop"

83− covarSamp = unsafeWindowFunctionN "covar_samp"

84− regrAvgX = unsafeWindowFunctionN "regr_avgx"

85− regrAvgY = unsafeWindowFunctionN "regr_avgy"

86− regrCount = unsafeWindowFunctionN "regr_count"

87− regrIntercept = unsafeWindowFunctionN "regr_intercept"

88− regrR2 = unsafeWindowFunctionN "regr_r2"

89− regrSlope = unsafeWindowFunctionN "regr_slope"

90− regrSxx = unsafeWindowFunctionN "regr_sxx"

91− regrSxy = unsafeWindowFunctionN "regr_sxy"

92− regrSyy = unsafeWindowFunctionN "regr_syy"

93− stddev = unsafeWindowFunction1 "stddev"

94− stddevPop = unsafeWindowFunction1 "stddev_pop"

95− stddevSamp = unsafeWindowFunction1 "stddev_samp"

96− variance = unsafeWindowFunction1 "variance"

97− varPop = unsafeWindowFunction1 "var_pop"

98− varSamp = unsafeWindowFunction1 "var_samp"

99−

100−-- | A `WindowDefinition` is a set of table rows that are somehow related

101−-- to the current row

102−data WindowDefinition outer commons grp schemas params from where

103− WindowDefinition

104− :: SOP.SListI bys

105− => NP (Expression outer commons grp schemas params from) bys

106− -- ^ `partitionBy` clause

107− -> [SortExpression outer commons grp schemas params from]

108− -- ^ `Squeal.PostgreSQL.Expression.Sort.orderBy` clause

109− -> WindowDefinition outer commons grp schemas params from

110−

111−instance OrderBy WindowDefinition where

112− orderBy sortsR (WindowDefinition parts sortsL)

113− = WindowDefinition parts (sortsL ++ sortsR)

114−

115−instance RenderSQL (WindowDefinition outer commons schemas from grp params) where

116− renderSQL (WindowDefinition part ord) =

117− renderPartitionByClause part <> renderOrderByClause ord

118− where

119− renderPartitionByClause = \case

120− Nil -> ""

121− parts -> "PARTITION" <+> "BY" <+> renderCommaSeparated renderExpression parts

122− renderOrderByClause = \case

123− [] -> ""

124− srts -> " ORDER" <+> "BY"

125− <+> commaSeparated (renderSQL <$> srts)

126−

127−{- |

128−The `partitionBy` clause within `Squeal.PostgreSQL.Query.Over` divides the rows into groups,

129−or partitions, that share the same values of the `partitionBy` `Expression`(s).

130−For each row, the window function is computed across the rows that fall into

131−the same partition as the current row.

132−-}

133−partitionBy

134− :: SOP.SListI bys

135− => NP (Expression outer commons grp schemas params from) bys -- ^ partitions

136− -> WindowDefinition outer commons grp schemas params from

137−partitionBy bys = WindowDefinition bys []

138−

139−{- |

140−A window function performs a calculation across a set of table rows

141−that are somehow related to the current row. This is comparable to the type

142−of calculation that can be done with an aggregate function.

143−However, window functions do not cause rows to become grouped into a single

144−output row like non-window aggregate calls would.

145−Instead, the rows retain their separate identities.

146−Behind the scenes, the window function is able to access more than

147−just the current row of the query result.

148−-}

149−newtype WindowFunction

150− (outer :: FromType)

151− (commons :: FromType)

152− (grp :: Grouping)

153− (schemas :: SchemasType)

154− (params :: [NullityType])

155− (from :: FromType)

156− (ty :: NullityType)

157− = UnsafeWindowFunction { renderWindowFunction :: ByteString }

158− deriving (GHC.Generic,Show,Eq,Ord,NFData)

159−

160−instance RenderSQL (WindowFunction outer commons grp schemas params from ty) where

161− renderSQL = renderWindowFunction

162−

163−{- |

164−A @RankNType@ for window functions with no arguments.

165−-}

166−type WinFun0 x

167− = forall outer commons grp schemas params from

168− . WindowFunction outer commons grp schemas params from x

169− -- ^ cannot reference aliases

170−

171−{- |

172−A @RankNType@ for window functions with 1 argument.

173−-}

174−type WinFun1 x y

175− = forall outer commons grp schemas params from

176− . Expression outer commons grp schemas params from x

177− -- ^ input

178− -> WindowFunction outer commons grp schemas params from y

179− -- ^ output

180−

181−{- | A @RankNType@ for window functions with a fixed-length

182−list of heterogeneous arguments.

183−Use the `*:` operator to end your argument lists.

184−-}

185−type WinFunN xs y

186− = forall outer commons grp schemas params from

187− . NP (Expression outer commons grp schemas params from) xs

188− -- ^ inputs

189− -> WindowFunction outer commons grp schemas params from y

190− -- ^ output

191−

192−-- | escape hatch for defining window functions

193−unsafeWindowFunction1 :: ByteString -> WinFun1 x y

194−unsafeWindowFunction1 fun x

195− = UnsafeWindowFunction $ fun <> parenthesized (renderSQL x)

196−

197−-- | escape hatch for defining multi-argument window functions

198−unsafeWindowFunctionN :: SOP.SListI xs => ByteString -> WinFunN xs y

199−unsafeWindowFunctionN fun xs = UnsafeWindowFunction $ fun <>

200− parenthesized (renderCommaSeparated renderSQL xs)

201−

202−{- | rank of the current row with gaps; same as `rowNumber` of its first peer

203−

204−>>> printSQL rank

205−rank()

206−-}

207−rank :: WinFun0 ('NotNull 'PGint8)

208−rank = UnsafeWindowFunction "rank()"

209−

210−{- | number of the current row within its partition, counting from 1

211−

212−>>> printSQL rowNumber

213−row_number()

214−-}

215−rowNumber :: WinFun0 ('NotNull 'PGint8)

216−rowNumber = UnsafeWindowFunction "row_number()"

217−

218−{- | rank of the current row without gaps; this function counts peer groups

219−

220−>>> printSQL denseRank

221−dense_rank()

222−-}

223−denseRank :: WinFun0 ('NotNull 'PGint8)

224−denseRank = UnsafeWindowFunction "dense_rank()"

225−

226−{- | relative rank of the current row: (rank - 1) / (total partition rows - 1)

227−

228−>>> printSQL percentRank

229−percent_rank()

230−-}

231−percentRank :: WinFun0 ('NotNull 'PGfloat8)

232−percentRank = UnsafeWindowFunction "percent_rank()"

233−

234−{- | cumulative distribution: (number of partition rows

235−preceding or peer with current row) / total partition rows

236−

237−>>> printSQL cumeDist

238−cume_dist()

239−-}

240−cumeDist :: WinFun0 ('NotNull 'PGfloat8)

241−cumeDist = UnsafeWindowFunction "cume_dist()"

242−

243−{- | integer ranging from 1 to the argument value,

244−dividing the partition as equally as possible

245−

246−>>> printSQL $ ntile 5

247−ntile(5)

248−-}

249−ntile :: WinFun1 ('NotNull 'PGint4) ('NotNull 'PGint4)

250−ntile = unsafeWindowFunction1 "ntile"

251−

252−{- | returns value evaluated at the row that is offset rows before the current

253−row within the partition; if there is no such row, instead return default

254−(which must be of the same type as value). Both offset and default are

255−evaluated with respect to the current row.

256−-}

257−lag :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty

258−lag = unsafeWindowFunctionN "lag"

259−

260−{- | returns value evaluated at the row that is offset rows after the current

261−row within the partition; if there is no such row, instead return default

262−(which must be of the same type as value). Both offset and default are

263−evaluated with respect to the current row.

264−-}

265−lead :: WinFunN '[ty, 'NotNull 'PGint4, ty] ty

266−lead = unsafeWindowFunctionN "lead"

267−

268−{- | returns value evaluated at the row that is the

269−first row of the window frame

270−-}

271−firstValue :: WinFun1 ty ty

272−firstValue = unsafeWindowFunction1 "first_value"

273−

274−{- | returns value evaluated at the row that is the

275−last row of the window frame

276−-}

277−lastValue :: WinFun1 ty ty

278−lastValue = unsafeWindowFunction1 "last_value"

279−

280−{- | returns value evaluated at the row that is the nth

281−row of the window frame (counting from 1); null if no such row

282−-}

283−nthValue :: WinFunN '[null ty, 'NotNull 'PGint4] ('Null ty)

284−nthValue = unsafeWindowFunctionN "nth_value"

squeal-postgresql/src/Squeal/PostgreSQL/List.hsdeleted−112

@@ -1,112 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.List

3−Description: List related types and functions

4−Copyright: (c) Eitan Chatav, 2019

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−Haskell singly-linked lists are very powerful. This module

9−provides functionality for type-level lists, heterogeneous

10−lists and type aligned lists.

11−-}

12−

13−{-# LANGUAGE

14− DataKinds

15− , FlexibleContexts

16− , GADTs

17− , LambdaCase

18− , MultiParamTypeClasses

19− , OverloadedStrings

20− , PolyKinds

21− , QuantifiedConstraints

22− , RankNTypes

23− , ScopedTypeVariables

24− , TypeApplications

25− , TypeFamilies

26− , TypeOperators

27− , UndecidableInstances

28−#-}

29−

30−module Squeal.PostgreSQL.List

31− ( SOP.NP (..)

32− , (*:)

33− , Join

34− , disjoin

35− , Additional (..)

36− , Path (..)

37− , CFunctor (..)

38− , CFoldable (..)

39− , CFree (..)

40− , Elem

41− , In

42− , Length

43− ) where

44−

45−import Control.Category.Free

46−import Data.Function ((&))

47−import Data.Kind

48−import Data.Type.Bool

49−import GHC.TypeLits

50−

51−import Generics.SOP as SOP

52−

53−-- | `Join` is simply promoted `++` and is used in @JOIN@s in

54−-- `Squeal.PostgreSQL.Query.FromClause`s.

55−type family Join xs ys where

56− Join '[] ys = ys

57− Join (x ': xs) ys = x ': Join xs ys

58−

59−-- | `disjoin` is a utility function for splitting an `NP` list into pieces.

60−disjoin

61− :: forall xs ys expr. SListI xs

62− => NP expr (Join xs ys)

63− -> (NP expr xs, NP expr ys)

64−disjoin = case sList @xs of

65− SNil -> \ys -> (Nil, ys)

66− SCons -> \(x :* xsys) ->

67− case disjoin xsys of (xs,ys) -> (x :* xs, ys)

68−

69−-- | The `Additional` class is for appending

70−-- type-level list parameterized constructors such as `NP`,

71−-- `Squeal.PostgreSQL.Query.Selection`, and `Squeal.PostgreSQL.Query.FromClause`.

72−class Additional expr where

73− also :: expr ys -> expr xs -> expr (Join xs ys)

74−instance Additional (NP expr) where

75− also ys = \case

76− Nil -> ys

77− x :* xs -> x :* (xs & also ys)

78−

79−-- | A useful operator for ending an `NP` list of length at least 2 without `Nil`.

80−(*:) :: f x -> f y -> NP f '[x,y]

81−x *: y = x :* y :* Nil

82−infixl 9 *:

83−

84−-- | @Elem@ is a promoted `Data.List.elem`.

85−type family Elem x xs where

86− Elem x '[] = 'False

87− Elem x (x ': _) = 'True

88− Elem x (_ ': x ': _) = 'True

89− Elem x (_ ': _ ': x ': _) = 'True

90− Elem x (_ ': _ ': _ ': x ': _) = 'True

91− Elem x (_ ': _ ': _ ': _ ': x ': _) = 'True

92− Elem x (_ ': _ ': _ ': _ ': _ ': x ': _) = 'True

93− Elem x (_ ': xs) = Elem x xs

94−

95−-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

96−type family In x xs :: Constraint where

97− In x xs = If (Elem x xs) (() :: Constraint)

98− (TypeError ('ShowType x ':<>: 'Text " is not in " ':<>: 'ShowType xs))

99−

100−{- | Calculate the `Length` of a type level list

101−

102−>>> :kind! Length '[Char,String,Bool,Double]

103−Length '[Char,String,Bool,Double] :: Nat

104−= 4

105−-}

106−type family Length (xs :: [k]) :: Nat where

107− Length (_ ': _ ': _ ': _ ': _ : xs) = 5 + Length xs

108− Length (_ ': _ ': _ ': _ : xs) = 4 + Length xs

109− Length (_ ': _ ': _ : xs) = 3 + Length xs

110− Length (_ ': _ : xs) = 2 + Length xs

111− Length (_ : xs) = 1 + Length xs

112− Length '[] = 0

squeal-postgresql/src/Squeal/PostgreSQL/Manipulation.hs+364−434

@@ -11,568 +11,498 @@ Squeal data manipulation language.

11{-# LANGUAGE

12 DeriveGeneric

13 , FlexibleContexts

14− , FlexibleInstances

15 , GADTs

14 , GADTs

16 , GeneralizedNewtypeDeriving

15 , GeneralizedNewtypeDeriving

17 , LambdaCase

16 , LambdaCase

18− , MultiParamTypeClasses

19 , OverloadedStrings

17 , OverloadedStrings

20− , PatternSynonyms

21− , QuantifiedConstraints

22 , RankNTypes

18 , RankNTypes

23− , ScopedTypeVariables

24− , TypeApplications

25− , TypeFamilies

26 , TypeInType

19 , TypeInType

27 , TypeOperators

20 , TypeOperators

28− , UndecidableInstances

29#-}

21#-}

31module Squeal.PostgreSQL.Manipulation

23module Squeal.PostgreSQL.Manipulation

32 ( -- * Manipulation

24 ( -- * Manipulation

33− Manipulation_

34− , Manipulation (..)

25+ Manipulation (UnsafeManipulation, renderManipulation)

35 , queryStatement

26 , queryStatement

27+ , ColumnValue (..)

28+ , ReturningClause (ReturningStar, Returning)

29+ , ConflictClause (OnConflictDoRaise, OnConflictDoNothing, OnConflictDoUpdate)

36 -- * Insert

30 -- * Insert

37− , insertInto

31+ , insertRows

38− , insertInto_

32+ , insertRow

33+ , insertRows_

34+ , insertRow_

35+ , insertQuery

36+ , insertQuery_

37+ , renderReturningClause

38+ , renderConflictClause

39 -- * Update

40 , update

41 , update_

42 -- * Delete

43 , deleteFrom

44 , deleteFrom_

45− -- * Clauses

45+ -- * With

46− , Optional (..)

46+ , with

47− , QueryClause (..)

48− , pattern Values_

49− , ReturningClause (..)

50− , pattern Returning_

51− , ConflictClause (..)

52− , ConflictTarget (..)

53− , ConflictAction (..)

54− , UsingClause (..)

55 ) where

47 ) where

57import Control.DeepSeq

49import Control.DeepSeq

58import Data.ByteString hiding (foldr)

50import Data.ByteString hiding (foldr)

59−import Data.Kind (Type)

51+import Data.Monoid

53+import qualified Data.ByteString as ByteString

61import qualified Generics.SOP as SOP

54import qualified Generics.SOP as SOP

62import qualified GHC.Generics as GHC

55import qualified GHC.Generics as GHC

64−import Squeal.PostgreSQL.Alias

65import Squeal.PostgreSQL.Expression

57import Squeal.PostgreSQL.Expression

66−import Squeal.PostgreSQL.Expression.Logic

67−import Squeal.PostgreSQL.List

68−import Squeal.PostgreSQL.PG

69import Squeal.PostgreSQL.Render

58import Squeal.PostgreSQL.Render

70import Squeal.PostgreSQL.Query

59import Squeal.PostgreSQL.Query

71import Squeal.PostgreSQL.Schema

60import Squeal.PostgreSQL.Schema

73−-- $setup

74−-- >>> import Squeal.PostgreSQL

75−-- >>> import Data.Int

76−-- >>> import Data.Time

77−

78{- |

62{- |

79A `Manipulation` is a statement which may modify data in the database,

63A `Manipulation` is a statement which may modify data in the database,

80−but does not alter its schemas. Examples are inserts, updates and deletes.

64+but does not alter the schema. Examples are inserts, updates and deletes.

81A `Query` is also considered a `Manipulation` even though it does not modify data.

65A `Query` is also considered a `Manipulation` even though it does not modify data.

83−The general `Manipulation` type is parameterized by

84−

85−* @commons :: FromType@ - scope for all `common` table expressions,

86−* @schemas :: SchemasType@ - scope for all `table`s and `view`s,

87−* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,

88−* @row :: RowType@ - return type of the `Query`.

89−-}

90−newtype Manipulation

91− (commons :: FromType)

92− (schemas :: SchemasType)

93− (params :: [NullityType])

94− (columns :: RowType)

95− = UnsafeManipulation { renderManipulation :: ByteString }

96− deriving (GHC.Generic,Show,Eq,Ord,NFData)

97−instance RenderSQL (Manipulation commons schemas params columns) where

98− renderSQL = renderManipulation

99−instance With Manipulation where

100− with Done manip = manip

101− with ctes manip = UnsafeManipulation $

102− "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL manip

103−

104−{- |

105−The top level `Manipulation_` type is parameterized by a @schemas@ `SchemasType`,

106−against which the query is type-checked, an input @parameters@ Haskell `Type`,

107−and an ouput row Haskell `Type`.

108−

109−A top-level `Manipulation_` can be run

110−using `Squeal.PostgreSQL.PQ.manipulateParams`, or if @parameters = ()@

111−using `Squeal.PostgreSQL.PQ.manipulate`.

112−

113−Generally, @parameters@ will be a Haskell tuple or record whose entries

114−may be referenced using positional

115−`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a

116−Haskell record, whose entries will be targeted using overloaded labels.

117−

118−>>> :set -XDeriveAnyClass -XDerivingStrategies

119−>>> :{

120−data Row a b = Row { col1 :: a, col2 :: b }

121− deriving stock (GHC.Generic)

122− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

123−:}

124−

125simple insert:

67simple insert:

126

127−>>> type Columns = '["col1" ::: 'NoDef :=> 'Null 'PGint4, "col2" ::: 'Def :=> 'NotNull 'PGint4]

128−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

129>>> :{

69>>> :{

130let

70let

131− manipulation :: Manipulation_ (Public Schema) () ()

71+ manipulation :: Manipulation

72+ '[ "tab" ::: 'Table ('[] :=>

73+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

74+ , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[] '[]

132 manipulation =

75 manipulation =

133− insertInto_ #tab (Values_ (Set 2 `as` #col1 :* Default `as` #col2))

76+ insertRow_ #tab (Set 2 `As` #col1 :* Default `As` #col2 :* Nil)

134−in printSQL manipulation

77+in renderManipulation manipulation

135:}

78:}

136−INSERT INTO "tab" ("col1", "col2") VALUES (2, DEFAULT)

79+"INSERT INTO \"tab\" (\"col1\", \"col2\") VALUES (2, DEFAULT);"

137

138parameterized insert:

81parameterized insert:

139

140−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]

141−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

142>>> :{

83>>> :{

143let

84let

144− manipulation :: Manipulation_ (Public Schema) (Int32, Int32) ()

85+ manipulation :: Manipulation

86+ '[ "tab" ::: 'Table ('[] :=>

87+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

88+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

89+ '[ 'NotNull 'PGint4, 'NotNull 'PGint4 ] '[]

145 manipulation =

90 manipulation =

91+ insertRow_ #tab

146− insertInto_ #tab (Values_ (Set (param @1) `as` #col1 :* Set (param @2) `as` #col2))

92+ (Set (param @1) `As` #col1 :* Set (param @2) `As` #col2 :* Nil)

147−in printSQL manipulation

93+in renderManipulation manipulation

148:}

94:}

149−INSERT INTO "tab" ("col1", "col2") VALUES (($1 :: int4), ($2 :: int4))

95+"INSERT INTO \"tab\" (\"col1\", \"col2\") VALUES (($1 :: int4), ($2 :: int4));"

150

151returning insert:

97returning insert:

152

153>>> :{

99>>> :{

154let

100let

155− manipulation :: Manipulation_ (Public Schema) () (Only Int32)

101+ manipulation :: Manipulation

102+ '[ "tab" ::: 'Table ('[] :=>

103+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

104+ , "col2" ::: 'Def :=> 'NotNull 'PGint4 ])] '[]

105+ '["fromOnly" ::: 'NotNull 'PGint4]

156 manipulation =

106 manipulation =

157− insertInto #tab (Values_ (Set 2 `as` #col1 :* Set 3 `as` #col2))

107+ insertRow #tab (Set 2 `As` #col1 :* Default `As` #col2 :* Nil)

158− OnConflictDoRaise (Returning (#col1 `as` #fromOnly))

108+ OnConflictDoRaise (Returning (#col1 `As` #fromOnly :* Nil))

159−in printSQL manipulation

109+in renderManipulation manipulation

160:}

110:}

161−INSERT INTO "tab" ("col1", "col2") VALUES (2, 3) RETURNING "col1" AS "fromOnly"

111+"INSERT INTO \"tab\" (\"col1\", \"col2\") VALUES (2, DEFAULT) RETURNING \"col1\" AS \"fromOnly\";"

162

112

163upsert:

113upsert:

164

114

165−>>> type CustomersColumns = '["name" ::: 'NoDef :=> 'NotNull 'PGtext, "email" ::: 'NoDef :=> 'NotNull 'PGtext]

166−>>> type CustomersConstraints = '["uq" ::: 'Unique '["name"]]

167−>>> type CustomersSchema = '["customers" ::: 'Table (CustomersConstraints :=> CustomersColumns)]

168>>> :{

115>>> :{

169let

116let

170− manipulation :: Manipulation_ (Public CustomersSchema) () ()

117+ manipulation :: Manipulation

118+ '[ "tab" ::: 'Table ('[] :=>

119+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

120+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

121+ '[] '[ "sum" ::: 'NotNull 'PGint4]

171 manipulation =

122 manipulation =

172− insertInto #customers

123+ insertRows #tab

173− (Values_ (Set "John Smith" `as` #name :* Set "john@smith.com" `as` #email))

124+ (Set 2 `As` #col1 :* Set 4 `As` #col2 :* Nil)

174− (OnConflict (OnConstraint #uq)

125+ [Set 6 `As` #col1 :* Set 8 `As` #col2 :* Nil]

175− (DoUpdate (Set (#excluded ! #email <> "; " <> #customers ! #email) `as` #email) []))

126+ (OnConflictDoUpdate

176− (Returning_ Nil)

127+ (Set 2 `As` #col1 :* Same `As` #col2 :* Nil)

128+ [#col1 .== #col2])

129+ (Returning $ (#col1 + #col2) `As` #sum :* Nil)

177−in printSQL manipulation

130+in renderManipulation manipulation

178:}

131:}

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"))

132+"INSERT INTO \"tab\" (\"col1\", \"col2\") VALUES (2, 4), (6, 8) ON CONFLICT DO UPDATE SET \"col1\" = 2 WHERE (\"col1\" = \"col2\") RETURNING (\"col1\" + \"col2\") AS \"sum\";"

180

133

181query insert:

134query insert:

182

135

183>>> :{

136>>> :{

184let

137let

185− manipulation :: Manipulation_ (Public Schema) () ()

138+ manipulation :: Manipulation

186− manipulation = insertInto_ #tab (Subquery (select Star (from (table #tab))))

139+ '[ "tab" ::: 'Table ('[] :=>

140+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

141+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4

142+ ])

143+ , "other_tab" ::: 'Table ('[] :=>

144+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

145+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4

146+ ])

147+ ] '[] '[]

148+ manipulation =

149+ insertQuery_ #tab

150+ (selectStar (from (table (#other_tab `As` #t))))

187−in printSQL manipulation

151+in renderManipulation manipulation

188:}

152:}

189−INSERT INTO "tab" SELECT * FROM "tab" AS "tab"

153+"INSERT INTO \"tab\" SELECT * FROM \"other_tab\" AS \"t\";"

190

154

191update:

155update:

192

156

193>>> :{

157>>> :{

194let

158let

195− manipulation :: Manipulation_ (Public Schema) () ()

159+ manipulation :: Manipulation

196− manipulation = update_ #tab (Set 2 `as` #col1) (#col1 ./= #col2)

197−in printSQL manipulation

198−:}

199−UPDATE "tab" SET "col1" = 2 WHERE ("col1" <> "col2")

200−

201−delete:

202−

203−>>> :{

204−let

205− manipulation :: Manipulation_ (Public Schema) () (Row Int32 Int32)

206− manipulation = deleteFrom #tab NoUsing (#col1 .== #col2) (Returning Star)

207−in printSQL manipulation

208−:}

209−DELETE FROM "tab" WHERE ("col1" = "col2") RETURNING *

210−

211−delete and using clause:

212−

213−>>> :{

214−type Schema3 =

215− '[ "tab" ::: 'Table ('[] :=> Columns)

160+ '[ "tab" ::: 'Table ('[] :=>

216− , "other_tab" ::: 'Table ('[] :=> Columns)

161+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

217− , "third_tab" ::: 'Table ('[] :=> Columns) ]

162+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[] '[]

218−:}

219−

220−>>> :{

221−let

222− manipulation :: Manipulation_ (Public Schema3) () ()

223 manipulation =

163 manipulation =

224− deleteFrom #tab (Using (table #other_tab & also (table #third_tab)))

164+ update_ #tab (Set 2 `As` #col1 :* Same `As` #col2 :* Nil)

225− ( (#tab ! #col2 .== #other_tab ! #col2)

165+ (#col1 ./= #col2)

226− .&& (#tab ! #col2 .== #third_tab ! #col2) )

227− (Returning_ Nil)

228−in printSQL manipulation

166+in renderManipulation manipulation

229:}

167:}

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"))

168+"UPDATE \"tab\" SET \"col1\" = 2 WHERE (\"col1\" <> \"col2\");"

231

169

232−with manipulation:

170+delete:

233

171

234−>>> type ProductsColumns = '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

235−>>> type ProductsSchema = '["products" ::: 'Table ('[] :=> ProductsColumns), "products_deleted" ::: 'Table ('[] :=> ProductsColumns)]

236>>> :{

172>>> :{

237let

173let

238− manipulation :: Manipulation_ (Public ProductsSchema) (Only Day) ()

174+ manipulation :: Manipulation

239− manipulation = with

175+ '[ "tab" ::: 'Table ('[] :=>

240− (deleteFrom #products NoUsing (#date .< param @1) (Returning Star) `as` #del)

176+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

241− (insertInto_ #products_deleted (Subquery (select Star (from (common #del)))))

177+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])] '[]

178+ '[ "col1" ::: 'NotNull 'PGint4

179+ , "col2" ::: 'NotNull 'PGint4 ]

180+ manipulation = deleteFrom #tab (#col1 .== #col2) ReturningStar

242−in printSQL manipulation

181+in renderManipulation manipulation

243:}

182:}

244−WITH "del" AS (DELETE FROM "products" WHERE ("date" < ($1 :: date)) RETURNING *) INSERT INTO "products_deleted" SELECT * FROM "del" AS "del"

183+"DELETE FROM \"tab\" WHERE (\"col1\" = \"col2\") RETURNING *;"

245-}

184-}

246−type family Manipulation_ (schemas :: SchemasType) (params :: Type) (row :: Type) where

185+newtype Manipulation

247− Manipulation_ schemas params row = Manipulation '[] schemas (TuplePG params) (RowPG row)

186+ (schema :: SchemaType)

187+ (params :: [NullityType])

188+ (columns :: RelationType)

189+ = UnsafeManipulation { renderManipulation :: ByteString }

190+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

248

191

249-- | Convert a `Query` into a `Manipulation`.

192-- | Convert a `Query` into a `Manipulation`.

250queryStatement

193queryStatement

251− :: Query '[] commons schemas params columns

194+ :: Query schema params columns

252− -- ^ `Query` to embed as a `Manipulation`

253− -> Manipulation commons schemas params columns

195+ -> Manipulation schema params columns

254−queryStatement q = UnsafeManipulation $ renderSQL q

196+queryStatement q = UnsafeManipulation $ renderQuery q <> ";"

255

197

256{-----------------------------------------

198{-----------------------------------------

257INSERT statements

199INSERT statements

258-----------------------------------------}

200-----------------------------------------}

259

201

260−{- |

202+-- | Insert multiple rws.

203+--

261−When a table is created, it contains no data. The first thing to do

204+-- 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

205+-- 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

206+-- conceptually inserted one rw 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.

207+-- more than one rw, but there is no way to insert less than one rw.

265−Even if you know only some column values, a complete row must be created.

208+-- Even if you know only some column values, a complete rw must be created.

266−-}

209+insertRows

267−insertInto

268− :: ( Has sch schemas schema

269− , Has tab schema ('Table table)

270− , columns ~ TableToColumns table

271− , row0 ~ TableToRow table

272− , SOP.SListI columns

210+ :: ( SOP.SListI columns

273− , SOP.SListI row1 )

211+ , SOP.SListI results

274− => QualifiedAlias sch tab

275− -- ^ table

276− -> QueryClause commons schemas params columns

277− -- ^ what to insert

278− -> ConflictClause tab commons schemas params table

279− -- ^ what to do in case of conflict

280− -> ReturningClause commons schemas params '[tab ::: row0] row1

281− -- ^ what to return

282− -> Manipulation commons schemas params row1

283−insertInto tab qry conflict ret = UnsafeManipulation $

284− "INSERT" <+> "INTO" <+> renderSQL tab

285− <+> renderSQL qry

286− <> renderSQL conflict

287− <> renderSQL ret

288−

289−-- | Like `insertInto` but with `OnConflictDoRaise` and `no` `ReturningClause`.

290−insertInto_

291− :: ( Has sch schemas schema

292 , Has tab schema ('Table table)

212 , Has tab schema ('Table table)

293− , columns ~ TableToColumns table

213+ , columns ~ TableToColumns table )

294− , row ~ TableToRow table

214+ => Alias tab -- ^ table to insert into

295− , SOP.SListI columns )

215+ -> NP (Aliased (ColumnValue '[] params)) columns -- ^ rw to insert

296− => QualifiedAlias sch tab

216+ -> [NP (Aliased (ColumnValue '[] params)) columns] -- ^ more rws to insert

297− -- ^ table

217+ -> ConflictClause columns params

298− -> QueryClause commons schemas params columns

218+ -- ^ what to do in case of constraint conflict

299− -- ^ what to insert

219+ -> ReturningClause columns params results -- ^ results to return

300− -> Manipulation commons schemas params '[]

220+ -> Manipulation schema params results

301−insertInto_ tab qry =

221+insertRows tab rw rws conflict returning = UnsafeManipulation $

302− insertInto tab qry OnConflictDoRaise (Returning_ Nil)

222+ "INSERT" <+> "INTO" <+> renderAlias tab

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)

223+ <+> parenthesized (renderCommaSeparated renderAliasPart rw)

330− <+> "VALUES"

224+ <+> "VALUES"

331− <+> commaSeparated

225+ <+> commaSeparated

332− ( parenthesized

226+ ( parenthesized

333− . renderCommaSeparated renderValuePart <$> row0 : rows )

227+ . renderCommaSeparated renderColumnValuePart <$> rw:rws )

334− Select row0 tab ->

228+ <> renderConflictClause conflict

335− parenthesized (renderCommaSeparatedMaybe renderSQLPartMaybe row0)

229+ <> renderReturningClause returning

336− <+> "SELECT"

337− <+> renderCommaSeparatedMaybe renderValuePartMaybe row0

338− <+> renderSQL tab

339− Subquery qry -> renderQuery qry

340 where

230 where

341− renderSQLPartMaybe, renderValuePartMaybe

231+ renderAliasPart, renderColumnValuePart

342− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

232+ :: Aliased (ColumnValue '[] params) ty -> ByteString

343− -> Maybe ByteString

233+ renderAliasPart (_ `As` name) = renderAlias name

344− renderSQLPartMaybe = \case

234+ renderColumnValuePart (value `As` _) = case value of

345− Default `As` _ -> Nothing

346− Set _ `As` name -> Just $ renderSQL name

347− renderValuePartMaybe = \case

348− Default `As` _ -> Nothing

235+ Default -> "DEFAULT"

349− Set value `As` _ -> Just $ renderExpression value

236+ Set expression -> renderExpression expression

350− renderSQLPart, renderValuePart

237+

351− :: Aliased (Optional (Expression '[] commons grp schemas params from)) column

238+-- | Insert a single rw.

352− -> ByteString

239+insertRow

353− renderSQLPart (_ `As` name) = renderSQL name

240+ :: ( SOP.SListI columns

354− renderValuePart (value `As` _) = renderSQL value

241+ , SOP.SListI results

355−

242+ , Has tab schema ('Table table)

356−-- | `Values_` describes a single `NP` list of `Aliased` `Optional` `Expression`s

243+ , columns ~ TableToColumns table )

357−-- whose `ColumnsType` must match the tables'.

244+ => Alias tab -- ^ table to insert into

358−pattern Values_

245+ -> NP (Aliased (ColumnValue '[] params)) columns -- ^ rw to insert

359− :: SOP.SListI columns

246+ -> ConflictClause columns params

360− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[]))) columns

247+ -- ^ what to do in case of constraint conflict

361− -- ^ row of values

248+ -> ReturningClause columns params results -- ^ results to return

362− -> QueryClause commons schemas params columns

249+ -> Manipulation schema params results

363−pattern Values_ vals = Values vals []

250+insertRow tab rw = insertRows tab rw []

364−

251+

365−-- | `Optional` is either `Default` or a value, parameterized by an appropriate

252+-- | Insert multiple rws returning `Nil` and raising an error on conflicts.

366−-- `ColumnConstraint`.

253+insertRows_

367−data Optional expr ty where

254+ :: ( SOP.SListI columns

368− -- | Use the `Default` value for a column.

255+ , Has tab schema ('Table table)

256+ , columns ~ TableToColumns table )

257+ => Alias tab -- ^ table to insert into

258+ -> NP (Aliased (ColumnValue '[] params)) columns -- ^ rw to insert

259+ -> [NP (Aliased (ColumnValue '[] params)) columns] -- ^ more rws to insert

260+ -> Manipulation schema params '[]

261+insertRows_ tab rw rws =

262+ insertRows tab rw rws OnConflictDoRaise (Returning Nil)

263+

264+-- | Insert a single rw returning `Nil` and raising an error on conflicts.

265+insertRow_

266+ :: ( SOP.SListI columns

267+ , Has tab schema ('Table table)

268+ , columns ~ TableToColumns table )

269+ => Alias tab -- ^ table to insert into

270+ -> NP (Aliased (ColumnValue '[] params)) columns -- ^ rw to insert

271+ -> Manipulation schema params '[]

272+insertRow_ tab rw = insertRow tab rw OnConflictDoRaise (Returning Nil)

273+

274+-- | Insert a `Query`.

275+insertQuery

276+ :: ( SOP.SListI columns

277+ , SOP.SListI results

278+ , Has tab schema ('Table table)

279+ , columns ~ TableToColumns table )

280+ => Alias tab -- ^ table to insert into

281+ -> Query schema params (ColumnsToRelation columns)

282+ -> ConflictClause columns params

283+ -- ^ what to do in case of constraint conflict

284+ -> ReturningClause columns params results -- ^ results to return

285+ -> Manipulation schema params results

286+insertQuery tab query conflict returning = UnsafeManipulation $

287+ "INSERT" <+> "INTO" <+> renderAlias tab

288+ <+> renderQuery query

289+ <> renderConflictClause conflict

290+ <> renderReturningClause returning

291+

292+-- | Insert a `Query` returning `Nil` and raising an error on conflicts.

293+insertQuery_

294+ :: ( SOP.SListI columns

295+ , Has tab schema ('Table table)

296+ , columns ~ TableToColumns table )

297+ => Alias tab -- ^ table to insert into

298+ -> Query schema params (ColumnsToRelation columns)

299+ -> Manipulation schema params '[]

300+insertQuery_ tab query =

301+ insertQuery tab query OnConflictDoRaise (Returning Nil)

302+

303+-- | `ColumnValue`s are values to insert or update in a rw

304+-- `Same` updates with the same value.

305+-- `Default` inserts or updates with the @DEFAULT@ value

306+-- `Set` a value to be an `Expression`, relative to the given

307+-- rw for an update, and closed for an insert.

308+data ColumnValue

309+ (columns :: RelationType)

310+ (params :: [NullityType])

311+ (ty :: ColumnType)

312+ where

313+ Same :: ColumnValue (column ': columns) params ty

369− Default :: Optional expr ('Def :=> ty)

314+ Default :: ColumnValue columns params ('Def :=> ty)

370− -- | `Set` a value for a column.

315+ Set

371− Set :: expr ty -> Optional expr (def :=> ty)

316+ :: (forall table. Expression '[table ::: columns] 'Ungrouped params ty)

372−

317+ -> ColumnValue columns params (constraint :=> ty)

373−instance (forall x. RenderSQL (expr x)) => RenderSQL (Optional expr ty) where

374− renderSQL = \case

375− Default -> "DEFAULT"

376− Set expr -> renderSQL expr

377

318

378-- | A `ReturningClause` computes and return value(s) based

319-- | A `ReturningClause` computes and return value(s) based

379−-- on each row actually inserted, updated or deleted. This is primarily

320+-- on each rw actually inserted, updated or deleted. This is primarily

380-- useful for obtaining values that were supplied by defaults, such as a

321-- useful for obtaining values that were supplied by defaults, such as a

381-- serial sequence number. However, any expression using the table's columns

322-- serial sequence number. However, any expression using the table's columns

382−-- is allowed. Only rows that were successfully inserted or updated or

323+-- is allowed. Only rws that were successfully inserted or updated or

383−-- deleted will be returned. For example, if a row was locked

324+-- deleted will be returned. For example, if a rw was locked

384−-- but not updated because an `OnConflict` `DoUpdate` condition was not satisfied,

325+-- but not updated because an `OnConflictDoUpdate` condition was not satisfied,

385−-- the row will not be returned. `Returning` `Star` will return all columns

326+-- the rw will not be returned. `ReturningStar` will return all columns

386−-- in the row. Use `Returning` `Nil` in the common case where no return

327+-- in the rw. Use @Returning Nil@ in the common case where no return

387-- values are desired.

328-- values are desired.

388−newtype ReturningClause commons schemas params from row =

329+data ReturningClause

389− Returning (Selection '[] commons 'Ungrouped schemas params from row)

330+ (columns :: ColumnsType)

390−

331+ (params :: [NullityType])

391−instance RenderSQL (ReturningClause commons schemas params from row) where

332+ (results :: RelationType)

392− renderSQL = \case

333+ where

393− Returning (List Nil) -> ""

334+ ReturningStar

394− Returning selection -> " RETURNING" <+> renderSQL selection

335+ :: results ~ ColumnsToRelation columns

395−

336+ => ReturningClause columns params results

396−-- | `Returning` a `List`

337+ Returning

397−pattern Returning_

338+ :: rel ~ ColumnsToRelation columns

339+ => NP (Aliased (Expression '[table ::: rel] 'Ungrouped params)) results

340+ -> ReturningClause columns params results

341+

342+-- | Render a `ReturningClause`.

343+renderReturningClause

398− :: SOP.SListI row

344+ :: SOP.SListI results

399− => NP (Aliased (Expression '[] commons 'Ungrouped schemas params from)) row

345+ => ReturningClause params columns results

400− -- ^ row of values

346+ -> ByteString

401− -> ReturningClause commons schemas params from row

347+renderReturningClause = \case

402−pattern Returning_ list = Returning (List list)

348+ ReturningStar -> " RETURNING *;"

349+ Returning Nil -> ";"

350+ Returning results -> " RETURNING"

351+ <+> renderCommaSeparated (renderAliasedAs renderExpression) results <> ";"

403

352

404-- | A `ConflictClause` specifies an action to perform upon a constraint

353-- | A `ConflictClause` specifies an action to perform upon a constraint

405-- violation. `OnConflictDoRaise` will raise an error.

354-- violation. `OnConflictDoRaise` will raise an error.

406−-- `OnConflict` `DoNothing` simply avoids inserting a row.

355+-- `OnConflictDoNothing` simply avoids inserting a rw.

407−-- `OnConflict` `DoUpdate` updates the existing row that conflicts with the row

356+-- `OnConflictDoUpdate` updates the existing rw that conflicts with the rw

408-- proposed for insertion.

357-- proposed for insertion.

409−data ConflictClause tab commons schemas params table where

358+data ConflictClause (columns :: ColumnsType) params where

410− OnConflictDoRaise :: ConflictClause tab commons schemas params table

359+ OnConflictDoRaise :: ConflictClause columns params

411− OnConflict

360+ OnConflictDoNothing :: ConflictClause columns params

412− :: ConflictTarget constraints

361+ OnConflictDoUpdate

413− -- ^ conflict target

362+ :: NP (Aliased (ColumnValue (ColumnsToRelation columns) params)) columns

414− -> ConflictAction tab commons schemas params columns

363+ -> [Condition '[table ::: ColumnsToRelation columns] 'Ungrouped params]

415− -- ^ conflict action

416− -> ConflictClause tab commons schemas params (constraints :=> columns)

364+ -> ConflictClause columns params

417

365

418-- | Render a `ConflictClause`.

366-- | Render a `ConflictClause`.

419−instance SOP.SListI (TableToColumns table)

367+renderConflictClause

420− => RenderSQL (ConflictClause tab commons schemas params table) where

368+ :: SOP.SListI columns

421− renderSQL = \case

369+ => ConflictClause columns params

422− OnConflictDoRaise -> ""

423− OnConflict target action -> " ON CONFLICT"

424− <+> renderSQL target <+> renderSQL action

425−

426−{- |

427−`ConflictAction` specifies an alternative `OnConflict` action.

428−It can be either `DoNothing`, or a `DoUpdate` clause specifying

429−the exact details of the `update` action to be performed in case of a conflict.

430−The `Set` and WHERE `Condition`s in `OnConflict` `DoUpdate` have access to the

431−existing row using the table's name (or an alias), and to rows proposed

432−for insertion using the special @#excluded@ table.

433−`OnConflict` `DoNothing` simply avoids inserting a row as its alternative action.

434−`OnConflict` `DoUpdate` updates the existing row that conflicts

435−with the row proposed for insertion as its alternative action.

436−-}

437−data ConflictAction tab commons schemas params columns where

438− DoNothing :: ConflictAction tab commons schemas params columns

439− DoUpdate

440− :: ( row ~ ColumnsToRow columns

441− , SOP.SListI columns

442− , columns ~ (col0 ': cols)

443− , SOP.All (HasIn columns) subcolumns

444− , AllUnique subcolumns )

445− => NP (Aliased (Optional (Expression '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]))) subcolumns

446− -> [Condition '[] commons 'Ungrouped schemas params '[tab ::: row, "excluded" ::: row]]

447− -- ^ WHERE `Condition`s

448− -> ConflictAction tab commons schemas params columns

449−

450−instance RenderSQL (ConflictAction tab commons schemas params columns) where

451− renderSQL = \case

452− DoNothing -> "DO NOTHING"

453− DoUpdate updates whs'

454− -> "DO UPDATE SET"

455− <+> renderCommaSeparated renderUpdate updates

456− <> case whs' of

457− [] -> ""

458− wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

459−

460−renderUpdate

461− :: (forall x. RenderSQL (expr x))

462− => Aliased (Optional expr) ty

463 -> ByteString

370 -> ByteString

464−renderUpdate (expr `As` col) = renderSQL col <+> "=" <+> renderSQL expr

371+renderConflictClause = \case

465−

372+ OnConflictDoRaise -> ""

466−-- | A `ConflictTarget` specifies the constraint violation that triggers a

373+ OnConflictDoNothing -> " ON CONFLICT DO NOTHING"

467−-- `ConflictAction`.

374+ OnConflictDoUpdate updates whs'

468−data ConflictTarget constraints where

375+ -> " ON CONFLICT DO UPDATE SET"

469− OnConstraint

376+ <+> renderCommaSeparatedMaybe renderUpdate updates

470− :: Has con constraints constraint

377+ <> case whs' of

471− => Alias con

378+ [] -> ""

472− -> ConflictTarget constraints

379+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

473−

380+ where

474−-- | Render a `ConflictTarget`

381+ renderUpdate

475−instance RenderSQL (ConflictTarget constraints) where

382+ :: Aliased (ColumnValue columns params) column

476− renderSQL (OnConstraint con) =

383+ -> Maybe ByteString

477− "ON" <+> "CONSTRAINT" <+> renderSQL con

384+ renderUpdate = \case

385+ Same `As` _ -> Nothing

386+ Default `As` column -> Just $

387+ renderAlias column <+> "=" <+> "DEFAULT"

388+ Set expression `As` column -> Just $

389+ renderAlias column <+> "=" <+> renderExpression expression

478

390

479{-----------------------------------------

391{-----------------------------------------

480UPDATE statements

392UPDATE statements

481-----------------------------------------}

393-----------------------------------------}

482

394

483-- | An `update` command changes the values of the specified columns

395-- | An `update` command changes the values of the specified columns

484−-- in all rows that satisfy the condition.

396+-- in all rws that satisfy the condition.

485update

397update

486 :: ( SOP.SListI columns

398 :: ( SOP.SListI columns

487− , SOP.SListI row1

399+ , SOP.SListI results

488− , Has sch schemas schema

489 , Has tab schema ('Table table)

400 , Has tab schema ('Table table)

490− , row0 ~ TableToRow table

491− , columns ~ TableToColumns table

401+ , columns ~ TableToColumns table )

492− , SOP.All (HasIn columns) subcolumns

493− , AllUnique subcolumns )

494− => QualifiedAlias sch tab -- ^ table to update

402+ => Alias tab -- ^ table to update

495− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row0]))) subcolumns

403+ -> NP (Aliased (ColumnValue (ColumnsToRelation columns) params)) columns

496 -- ^ modified values to replace old values

404 -- ^ modified values to replace old values

497− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row0]

405+ -> Condition '[tab ::: ColumnsToRelation columns] 'Ungrouped params

498− -- ^ condition under which to perform update on a row

406+ -- ^ condition under which to perform update on a rw

499− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

407+ -> ReturningClause columns params results -- ^ results to return

500− -> Manipulation commons schemas params row1

408+ -> Manipulation schema params results

501update tab columns wh returning = UnsafeManipulation $

409update tab columns wh returning = UnsafeManipulation $

502 "UPDATE"

410 "UPDATE"

503− <+> renderSQL tab

411+ <+> renderAlias tab

504 <+> "SET"

412 <+> "SET"

505− <+> renderCommaSeparated renderUpdate columns

413+ <+> renderCommaSeparatedMaybe renderUpdate columns

506− <+> "WHERE" <+> renderSQL wh

414+ <+> "WHERE" <+> renderExpression wh

507− <> renderSQL returning

415+ <> renderReturningClause returning

508−

416+ where

417+ renderUpdate

418+ :: Aliased (ColumnValue columns params) column

419+ -> Maybe ByteString

420+ renderUpdate = \case

421+ Same `As` _ -> Nothing

422+ Default `As` column -> Just $

423+ renderAlias column <+> "=" <+> "DEFAULT"

424+ Set expression `As` column -> Just $

425+ renderAlias column <+> "=" <+> renderExpression expression

426+

509−-- | Update a row returning `Nil`.

427+-- | Update a rw returning `Nil`.

510update_

428update_

511 :: ( SOP.SListI columns

429 :: ( SOP.SListI columns

512− , Has sch schemas schema

513 , Has tab schema ('Table table)

430 , Has tab schema ('Table table)

514− , row ~ TableToRow table

515− , columns ~ TableToColumns table

431+ , columns ~ TableToColumns table )

516− , SOP.All (HasIn columns) subcolumns

517− , AllUnique subcolumns )

518− => QualifiedAlias sch tab -- ^ table to update

432+ => Alias tab -- ^ table to update

519− -> NP (Aliased (Optional (Expression '[] '[] 'Ungrouped schemas params '[tab ::: row]))) subcolumns

433+ -> NP (Aliased (ColumnValue (ColumnsToRelation columns) params)) columns

520 -- ^ modified values to replace old values

434 -- ^ modified values to replace old values

521− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

435+ -> Condition '[tab ::: ColumnsToRelation columns] 'Ungrouped params

522− -- ^ condition under which to perform update on a row

436+ -- ^ condition under which to perform update on a rw

523− -> Manipulation commons schemas params '[]

437+ -> Manipulation schema params '[]

524−update_ tab columns wh = update tab columns wh (Returning_ Nil)

438+update_ tab columns wh = update tab columns wh (Returning Nil)

525

439

526{-----------------------------------------

440{-----------------------------------------

527DELETE statements

441DELETE statements

528-----------------------------------------}

442-----------------------------------------}

529

443

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.

444+-- | Delete rws of a table.

547deleteFrom

445deleteFrom

548− :: ( SOP.SListI row1

446+ :: ( SOP.SListI results

549− , Has sch schemas schema

550 , Has tab schema ('Table table)

447 , Has tab schema ('Table table)

551− , row0 ~ TableToRow table

552 , columns ~ TableToColumns table )

448 , columns ~ TableToColumns table )

553− => QualifiedAlias sch tab -- ^ table to delete from

449+ => Alias tab -- ^ table to delete from

554− -> UsingClause commons schemas params from

555− -> Condition '[] commons 'Ungrouped schemas params (tab ::: row0 ': from)

450+ -> Condition '[tab ::: ColumnsToRelation columns] 'Ungrouped params

556− -- ^ condition under which to delete a row

451+ -- ^ condition under which to delete a rw

557− -> ReturningClause commons schemas params '[tab ::: row0] row1 -- ^ results to return

452+ -> ReturningClause columns params results -- ^ results to return

558− -> Manipulation commons schemas params row1

453+ -> Manipulation schema params results

559−deleteFrom tab using wh returning = UnsafeManipulation $

454+deleteFrom tab wh returning = UnsafeManipulation $

560− "DELETE FROM"

455+ "DELETE FROM" <+> renderAlias tab

561− <+> renderSQL tab

456+ <+> "WHERE" <+> renderExpression wh

562− <> case using of

457+ <> renderReturningClause returning

563− NoUsing -> ""

458+

564− Using tables -> " USING" <+> renderSQL tables

565− <+> "WHERE" <+> renderSQL wh

566− <> renderSQL returning

567−

568−-- | Delete rows returning `Nil`.

459+-- | Delete rws returning `Nil`.

569deleteFrom_

460deleteFrom_

570− :: ( Has sch schemas schema

571− , Has tab schema ('Table table)

461+ :: ( Has tab schema ('Table table)

572− , row ~ TableToRow table

573 , columns ~ TableToColumns table )

462 , columns ~ TableToColumns table )

574− => QualifiedAlias sch tab -- ^ table to delete from

463+ => Alias tab -- ^ table to delete from

575− -> Condition '[] commons 'Ungrouped schemas params '[tab ::: row]

464+ -> Condition '[tab ::: ColumnsToRelation columns] 'Ungrouped params

576− -- ^ condition under which to delete a row

465+ -- ^ condition under which to delete a rw

577− -> Manipulation commons schemas params '[]

466+ -> Manipulation schema params '[]

578−deleteFrom_ tab wh = deleteFrom tab NoUsing wh (Returning_ Nil)

467+deleteFrom_ tab wh = deleteFrom tab wh (Returning Nil)

468+

469+{-----------------------------------------

470+WITH statements

471+-----------------------------------------}

472+

473+-- | `with` provides a way to write auxiliary statements for use in a larger statement.

474+-- These statements, which are often referred to as Common Table Expressions or CTEs,

475+-- can be thought of as defining temporary tables that exist just for one statement.

476+--

477+-- >>> type ProductsTable = '[] :=> '["product" ::: 'NoDef :=> 'NotNull 'PGtext, "date" ::: 'Def :=> 'NotNull 'PGdate]

478+--

479+-- >>> :{

480+-- let

481+-- manipulation :: Manipulation '["products" ::: 'Table ProductsTable, "products_deleted" ::: 'Table ProductsTable] '[ 'NotNull 'PGdate] '[]

482+-- manipulation = with

483+-- (deleteFrom #products (#date .< param @1) ReturningStar `As` #deleted_rws :* Nil)

484+-- (insertQuery_ #products_deleted (selectStar (from (view (#deleted_rws `As` #t)))))

485+-- in renderManipulation manipulation

486+-- :}

487+-- "WITH \"deleted_rws\" AS (DELETE FROM \"products\" WHERE (\"date\" < ($1 :: date)) RETURNING *) INSERT INTO \"products_deleted\" SELECT * FROM \"deleted_rws\" AS \"t\";"

488+with

489+ :: SOP.SListI commons

490+ => NP (Aliased (Manipulation schema params)) commons

491+ -- ^ common table expressions

492+ -> Manipulation (With commons schema) params results

493+ -> Manipulation schema params results

494+with commons manipulation = UnsafeManipulation $

495+ "WITH" <+> renderCommaSeparated renderCommon commons

496+ <+> renderManipulation manipulation

497+ where

498+ renderCommon

499+ :: Aliased (Manipulation schema params) common

500+ -> ByteString

501+ renderCommon (common `As` alias) =

502+ renderAlias alias <+> "AS" <+>

503+ let

504+ str = renderManipulation common

505+ len = ByteString.length str

506+ str' = ByteString.take (len - 1) str -- remove ';'

507+ in

508+ parenthesized str'

squeal-postgresql/src/Squeal/PostgreSQL/Migration.hs+216−348

@@ -8,13 +8,8 @@ Stability: experimental

8This module defines a `Migration` type to safely

9change the schema of your database over time. Let's see an example!

11−First turn on some extensions.

12−

13>>> :set -XDataKinds -XOverloadedLabels

11>>> :set -XDataKinds -XOverloadedLabels

14>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators

12>>> :set -XOverloadedStrings -XFlexibleContexts -XTypeOperators

15−

16−Next, let's define our `TableType`s.

17−

18>>> :{

13>>> :{

19type UsersTable =

14type UsersTable =

20 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

15 '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

@@ -25,7 +20,7 @@ type UsersTable =

26>>> :{

21>>> :{

27type EmailsTable =

22type EmailsTable =

28− '[ "pk_emails" ::: 'PrimaryKey '["id"]

23+ '[ "pk_emails" ::: 'PrimaryKey '["id"]

29 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]

24 , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]

30 ] :=>

25 ] :=>

31 '[ "id" ::: 'Def :=> 'NotNull 'PGint4

26 '[ "id" ::: 'Def :=> 'NotNull 'PGint4

@@ -34,293 +29,248 @@ type EmailsTable =

34 ]

29 ]

35:}

30:}

37−Now we can define some `Migration`s to make our tables.

38−

39>>> :{

32>>> :{

40let

33let

41− makeUsers :: Migration Definition (Public '[]) '["public" ::: '["users" ::: 'Table UsersTable]]

34+ makeUsers :: Migration IO '[] '["users" ::: 'Table UsersTable]

42 makeUsers = Migration

35 makeUsers = Migration

43 { name = "make users table"

36 { name = "make users table"

37+ , up = void . define $

44− , up = createTable #users

38+ createTable #users

45− ( serial `as` #id :*

39+ ( serial `As` #id :*

46− notNullable text `as` #name )

40+ (text & notNull) `As` #name :* Nil )

47− ( primaryKey #id `as` #pk_users )

41+ ( primaryKey #id `As` #pk_users :* Nil )

48− , down = dropTable #users

42+ , down = void . define $ dropTable #users

49 }

43 }

50:}

44:}

52>>> :{

46>>> :{

53let

47let

54− makeEmails :: Migration Definition '["public" ::: '["users" ::: 'Table UsersTable]]

48+ makeEmails :: Migration IO '["users" ::: 'Table UsersTable]

55− '["public" ::: '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]]

49+ '["users" ::: 'Table UsersTable, "emails" ::: 'Table EmailsTable]

56 makeEmails = Migration

50 makeEmails = Migration

57 { name = "make emails table"

51 { name = "make emails table"

52+ , up = void . define $

58− , up = createTable #emails

53+ createTable #emails

59− ( serial `as` #id :*

54+ ( serial `As` #id :*

60− notNullable int `as` #user_id :*

55+ (int & notNull) `As` #user_id :*

61− nullable text `as` #email )

56+ (text & null_) `As` #email :* Nil )

62− ( primaryKey #id `as` #pk_emails :*

57+ ( primaryKey #id `As` #pk_emails :*

63 foreignKey #user_id #users #id

58 foreignKey #user_id #users #id

64− OnDeleteCascade OnUpdateCascade `as` #fk_user_id )

59+ OnDeleteCascade OnUpdateCascade `As` #fk_user_id :* Nil )

65− , down = dropTable #emails

60+ , down = void . define $ dropTable #emails

66 }

61 }

67:}

62:}

69−Now that we have a couple migrations we can chain them together into a `Path`.

64+Now that we have a couple migrations we can chain them together.

71>>> let migrations = makeUsers :>> makeEmails :>> Done

66>>> let migrations = makeUsers :>> makeEmails :>> Done

73−Now run the migrations.

68+>>> :{

69+let

70+ numMigrations

71+ :: Has "schema_migrations" schema ('Table MigrationsTable)

72+ => PQ schema schema IO ()

73+ numMigrations = do

74+ result <- runQuery (selectStar (from (table (#schema_migrations `As` #m))))

75+ num <- ntuples result

76+ liftBase $ print num

77+:}

75−>>> import Control.Monad.IO.Class

76>>> :{

79>>> :{

77withConnection "host=localhost port=5432 dbname=exampledb" $

80withConnection "host=localhost port=5432 dbname=exampledb" $

78 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")

81 manipulate (UnsafeManipulation "SET client_min_messages TO WARNING;")

79 -- suppress notices

82 -- suppress notices

80− & pqThen (liftIO (putStrLn "Migrate"))

81 & pqThen (migrateUp migrations)

83 & pqThen (migrateUp migrations)

82− & pqThen (liftIO (putStrLn "Rollback"))

84+ & pqThen numMigrations

83 & pqThen (migrateDown migrations)

85 & pqThen (migrateDown migrations)

86+ & pqThen numMigrations

84:}

87:}

85−Migrate

88+Row 2

86−Rollback

89+Row 0

87−

88−We can also create a simple executable using `defaultMain`.

89−

90−>>> let main = defaultMain "host=localhost port=5432 dbname=exampledb" migrations

91−

92−>>> withArgs [] main

93−Invalid command: "". Use:

94−migrate to run all available migrations

95−rollback to rollback all available migrations

96−status to display migrations run and migrations left to run

97−

98−>>> withArgs ["status"] main

99−Migrations already run:

100− None

101−Migrations left to run:

102− - make users table

103− - make emails table

104−

105−>>> withArgs ["migrate"] main

106−Migrations already run:

107− - make users table

108− - make emails table

109−Migrations left to run:

110− None

111−

112−>>> withArgs ["rollback"] main

113−Migrations already run:

114− None

115−Migrations left to run:

116− - make users table

117− - make emails table

118−

119−In addition to enabling `Migration`s using pure SQL `Definition`s for

120−the `up` and `down` instructions, you can also perform impure `IO` actions

121−by using a `Migration`s over the `Terminally` `PQ` `IO` category.

122-}

90-}

123

124{-# LANGUAGE

92{-# LANGUAGE

125 DataKinds

93 DataKinds

126− , DeriveGeneric

127− , FlexibleContexts

128− , FlexibleInstances

129 , GADTs

94 , GADTs

130 , LambdaCase

95 , LambdaCase

131− , OverloadedLabels

132− , OverloadedStrings

133 , PolyKinds

96 , PolyKinds

134− , QuantifiedConstraints

97+ , OverloadedLabels

135− , RankNTypes

136 , TypeApplications

98 , TypeApplications

99+ , FlexibleContexts

137 , TypeOperators

100 , TypeOperators

138#-}

101#-}

139

102

140module Squeal.PostgreSQL.Migration

103module Squeal.PostgreSQL.Migration

141 ( -- * Migration

104 ( -- * Migration

142 Migration (..)

105 Migration (..)

143− , Migratory (..)

106+ , migrateUp

144− , Terminally (..)

107+ , migrateDown

145− , terminally

108+ -- * Aligned lists

146− , pureMigration

109+ , AlignedList (..)

110+ , single

111+ -- * Migration table

147 , MigrationsTable

112 , MigrationsTable

148− , defaultMain

113+ , createMigrations

114+ , insertMigration

115+ , deleteMigration

116+ , selectMigration

149 ) where

117 ) where

150

118

151import Control.Category

119import Control.Category

152import Control.Monad

120import Control.Monad

153−import Data.ByteString (ByteString)

121+import Control.Monad.Base

122+import Control.Monad.Trans.Control

154−import Data.Foldable (traverse_)

123+import Data.Monoid

124+import Generics.SOP (K(..))

155import Data.Function ((&))

125import Data.Function ((&))

156−import Data.List ((\\))

157import Data.Text (Text)

126import Data.Text (Text)

158−import Data.Time (UTCTime)

159−import Prelude hiding ((.), id)

127+import Prelude hiding (id, (.))

160−import System.Environment

161−import UnliftIO (MonadIO (..))

162−

163−import qualified Data.Text.IO as Text (putStrLn)

164−import qualified Generics.SOP as SOP

165−import qualified GHC.Generics as GHC

166

128

167−import Squeal.PostgreSQL.Alias

129+import Squeal.PostgreSQL

168−import Squeal.PostgreSQL.Binary

169−import Squeal.PostgreSQL.Definition

170−import Squeal.PostgreSQL.Definition.Table

171−import Squeal.PostgreSQL.Definition.Table.Constraint

172−import Squeal.PostgreSQL.Expression.Comparison

173−import Squeal.PostgreSQL.Expression.Parameter

174−import Squeal.PostgreSQL.Expression.Time

175−import Squeal.PostgreSQL.Expression.Type

176−import Squeal.PostgreSQL.List

177−import Squeal.PostgreSQL.Manipulation

178−import Squeal.PostgreSQL.PQ

179−import Squeal.PostgreSQL.Query

180−import Squeal.PostgreSQL.Schema

181−import Squeal.PostgreSQL.Transaction

182

130

183−-- | A `Migration` is a named "isomorphism" over a given category.

184−-- It should contain an inverse pair of `up` and `down`

131+-- | A `Migration` should contain an inverse pair of

185−-- instructions and a unique `name`.

132+-- `up` and `down` instructions and a unique `name`.

186−data Migration p schemas0 schemas1 = Migration

133+data Migration io schema0 schema1 = Migration

187 { name :: Text -- ^ The `name` of a `Migration`.

134 { name :: Text -- ^ The `name` of a `Migration`.

188 -- Each `name` in a `Migration` should be unique.

135 -- Each `name` in a `Migration` should be unique.

189− , up :: p schemas0 schemas1 -- ^ The `up` instruction of a `Migration`.

136+ , up :: PQ schema0 schema1 io () -- ^ The `up` instruction of a `Migration`.

190− , down :: p schemas1 schemas0 -- ^ The `down` instruction of a `Migration`.

137+ , down :: PQ schema1 schema0 io () -- ^ The `down` instruction of a `Migration`.

191− } deriving (GHC.Generic)

192−

193−{- |

194−A `Migratory` @p@ is a `Category` for which one can execute or rewind

195−a `Path` of `Migration`s over @p@. This includes the category of pure

196−SQL `Definition`s and the category of impure `Terminally` `PQ` `IO` actions.

197−-}

198−class Category p => Migratory p where

199−

200− {- |

201− Run a `Path` of `Migration`s.

202− Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

203− In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

204− if not, `up` the `Migration` and insert its `name` in the `MigrationsTable`.

205− -}

206− migrateUp

207− :: Path (Migration p) schemas0 schemas1

208− -> PQ schemas0 schemas1 IO ()

209−

210− {- |

211− Rewind a `Path` of `Migration`s.

212− Create the `MigrationsTable` as @public.schema_migrations@ if it does not already exist.

213− In one transaction, for each each `Migration` query to see if the `Migration` has been executed;

214− if so, `down` the `Migration` and delete its `name` in the `MigrationsTable`.

215− -}

216− migrateDown

217− :: Path (Migration p) schemas0 schemas1

218− -> PQ schemas1 schemas0 IO ()

219−

220−instance Migratory Definition where

221− migrateUp = migrateUp . cmap pureMigration

222− migrateDown = migrateDown . cmap pureMigration

223−

224−{- | `Terminally` turns an indexed monad transformer and the monad it transforms

225−into a category by restricting the return type to @()@ and permuting the type variables.

226−This is similar to how applying a monad to @()@ yields a monoid.

227−Since a `Terminally` action has a trivial return value, the only reason

228−to run one is for the side effects, in particular database and other IO effects.

229−-}

230−newtype Terminally trans monad x0 x1 = Terminally

231− { runTerminally :: trans x0 x1 monad () }

232− deriving GHC.Generic

233−

234−instance

235− ( IndexedMonadTransPQ trans

236− , Monad monad

237− , forall x0 x1. x0 ~ x1 => Monad (trans x0 x1 monad) )

238− => Category (Terminally trans monad) where

239− id = Terminally (return ())

240− Terminally g . Terminally f = Terminally $ pqThen g f

241−

242−-- | `terminally` ignores the output of a computation, returning @()@ and

243−-- wrapping it up into a `Terminally`. You can lift an action in the base monad

244−-- by using @terminally . lift@.

245−terminally

246− :: Functor (trans x0 x1 monad)

247− => trans x0 x1 monad ignore

248− -> Terminally trans monad x0 x1

249−terminally = Terminally . void

250−

251−-- | A `pureMigration` turns a `Migration` involving only pure SQL

252−-- `Definition`s into a `Migration` that may be combined with arbitrary `IO`.

253−pureMigration

254− :: Migration Definition schemas0 schemas1

255− -> Migration (Terminally PQ IO) schemas0 schemas1

256−pureMigration migration = Migration

257− { name = name migration

258− , up = terminally . define $ up migration

259− , down = terminally . define $ down migration

260 }

138 }

261

139

262−instance Migratory (Terminally PQ IO) where

140+-- | An `AlignedList` is a type-aligned list or free category.

263−

141+data AlignedList p x0 x1 where

264− migrateUp migration = unsafePQ . transactionally_ $ do

142+ Done :: AlignedList p x x

265− define createMigrations

143+ (:>>) :: p x0 x1 -> AlignedList p x1 x2 -> AlignedList p x0 x2

266− upMigrations migration

144+infixr 7 :>>

267−

145+instance Category (AlignedList p) where

268− where

146+ id = Done

269−

147+ (.) list = \case

270− upMigrations

271− :: Path (Migration (Terminally PQ IO)) schemas0 schemas1

272− -> PQ MigrationsSchemas MigrationsSchemas IO ()

273− upMigrations = \case

274− Done -> return ()

148+ Done -> list

275− step :>> steps -> upMigration step >> upMigrations steps

149+ step :>> steps -> step :>> (steps >>> list)

276−

150+

277− upMigration

151+-- | A `single` step.

278− :: Migration (Terminally PQ IO) schemas0 schemas1

152+single :: p x0 x1 -> AlignedList p x0 x1

279− -> PQ MigrationsSchemas MigrationsSchemas IO ()

153+single step = step :>> Done

280− upMigration step = do

154+

281− executed <- queryExecuted step

155+-- | Run `Migration`s by creating the `MigrationsTable`

282− unless (executed == 1) $ do

156+-- if it does not exist and then in a transaction, for each each `Migration`

283− unsafePQ . runTerminally $ up step

157+-- query to see if the `Migration` is executed. If not, then

284− manipulateParams_ insertMigration (Only (name step))

158+-- execute the `Migration` and insert its row in the `MigrationsTable`.

285−

159+migrateUp

286− queryExecuted

160+ :: MonadBaseControl IO io

287− :: Migration (Terminally PQ IO) schemas0 schemas1

161+ => AlignedList (Migration io) schema0 schema1 -- ^ migrations to run

288− -> PQ MigrationsSchemas MigrationsSchemas IO Row

162+ -> PQ

289− queryExecuted step = do

163+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

290− result <- runQueryParams selectMigration (Only (name step))

164+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

291− ntuples result

165+ io ()

292−

166+migrateUp migration =

293− migrateDown migrations = unsafePQ . transactionally_ $ do

167+ define createMigrations

294− define createMigrations

168+ & pqBind okResult

295− downMigrations migrations

169+ & pqThen (transactionallySchema_ (upMigrations migration))

296−

170+ where

297− where

298−

299− downMigrations

300− :: Path (Migration (Terminally PQ IO)) schemas0 schemas1

301− -> PQ MigrationsSchemas MigrationsSchemas IO ()

302− downMigrations = \case

303− Done -> return ()

304− step :>> steps -> downMigrations steps >> downMigration step

305−

306− downMigration

307− :: Migration (Terminally PQ IO) schemas0 schemas1

308− -> PQ MigrationsSchemas MigrationsSchemas IO ()

309− downMigration step = do

310− executed <- queryExecuted step

311− unless (executed == 0) $ do

312− unsafePQ . runTerminally $ down step

313− manipulateParams_ deleteMigration (Only (name step))

314

171

315− queryExecuted

172+ upMigrations

316− :: Migration (Terminally PQ IO) schemas0 schemas1

173+ :: MonadBaseControl IO io

317− -> PQ MigrationsSchemas MigrationsSchemas IO Row

174+ => AlignedList (Migration io) schema0 schema1

175+ -> PQ

176+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

177+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

178+ io ()

179+ upMigrations = \case

180+ Done -> return ()

181+ step :>> steps -> upMigration step & pqThen (upMigrations steps)

182+

183+ upMigration

184+ :: MonadBase IO io

185+ => Migration io schema0 schema1 -> PQ

186+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

187+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

188+ io ()

189+ upMigration step =

190+ queryExecuted step

191+ & pqBind (\ executed ->

192+ if executed == 1 -- up step has already been executed

193+ then PQ (\ _ -> return (K ())) -- unsafely switch schemas

194+ else

195+ pqEmbed (up step) -- safely switch schemas

196+ & pqThen (manipulateParams insertMigration (Only (name step)))

197+ -- insert execution record

198+ & pqBind okResult)

199+

200+ queryExecuted

201+ :: MonadBase IO io

202+ => Migration io schema0 schema1 -> PQ

203+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

204+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

205+ io Row

318− queryExecuted step = do

206+ queryExecuted step = do

319− result <- runQueryParams selectMigration (Only (name step))

207+ result <- runQueryParams selectMigration (Only (name step))

208+ okResult result

320− ntuples result

209+ ntuples result

210+

211+-- | Rewind `Migration`s by creating the `MigrationsTable`

212+-- if it does not exist and then in a transaction, for each each `Migration`

213+-- query to see if the `Migration` is executed. If it is, then

214+-- rewind the `Migration` and delete its row in the `MigrationsTable`.

215+migrateDown

216+ :: MonadBaseControl IO io

217+ => AlignedList (Migration io) schema0 schema1 -- ^ migrations to rewind

218+ -> PQ

219+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

220+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

221+ io ()

222+migrateDown migrations =

223+ define createMigrations

224+ & pqBind okResult

225+ & pqThen (transactionallySchema_ (downMigrations migrations))

226+ where

321

227

322−unsafePQ :: (Functor m) => PQ db0 db1 m x -> PQ db0' db1' m x

228+ downMigrations

323−unsafePQ (PQ pq) = PQ $ fmap (SOP.K . SOP.unK) . pq . SOP.K . SOP.unK

229+ :: MonadBaseControl IO io

230+ => AlignedList (Migration io) schema0 schema1 -> PQ

231+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

232+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

233+ io ()

234+ downMigrations = \case

235+ Done -> return ()

236+ step :>> steps -> downMigrations steps & pqThen (downMigration step)

237+

238+ downMigration

239+ :: MonadBase IO io

240+ => Migration io schema0 schema1 -> PQ

241+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

242+ ("schema_migrations" ::: 'Table MigrationsTable ': schema0)

243+ io ()

244+ downMigration step =

245+ queryExecuted step

246+ & pqBind (\ executed ->

247+ if executed == 0 -- up step has not been executed

248+ then PQ (\ _ -> return (K ())) -- unsafely switch schemas

249+ else

250+ pqEmbed (down step) -- safely switch schemas

251+ & pqThen (manipulateParams deleteMigration (Only (name step)))

252+ -- delete execution record

253+ & pqBind okResult)

254+

255+ queryExecuted

256+ :: MonadBase IO io

257+ => Migration io schema0 schema1 -> PQ

258+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

259+ ("schema_migrations" ::: 'Table MigrationsTable ': schema1)

260+ io Row

261+ queryExecuted step = do

262+ result <- runQueryParams selectMigration (Only (name step))

263+ okResult result

264+ ntuples result

265+

266+okResult :: MonadBase IO io => K Result results -> PQ schema schema io ()

267+okResult result = do

268+ status <- resultStatus result

269+ when (not (status `elem` [CommandOk, TuplesOk])) $ do

270+ errorMessageMaybe <- resultErrorMessage result

271+ case errorMessageMaybe of

272+ Nothing -> error "migrateDown: unknown error"

273+ Just msg -> error ("migrationDown: " <> show msg)

324

274

325-- | The `TableType` for a Squeal migration.

275-- | The `TableType` for a Squeal migration.

326type MigrationsTable =

276type MigrationsTable =

@@ -329,120 +279,38 @@ type MigrationsTable =

329 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz

279 , "executed_at" ::: 'Def :=> 'NotNull 'PGtimestamptz

330 ]

280 ]

331

281

332−data MigrationRow =

333− MigrationRow { migrationName :: Text

334− , migrationTime :: UTCTime }

335− deriving (GHC.Generic, Show)

336−

337−instance SOP.Generic MigrationRow

338−instance SOP.HasDatatypeInfo MigrationRow

339−

340−type MigrationsSchema = '["schema_migrations" ::: 'Table MigrationsTable]

341−type MigrationsSchemas = Public MigrationsSchema

342−

343-- | Creates a `MigrationsTable` if it does not already exist.

282-- | Creates a `MigrationsTable` if it does not already exist.

344−createMigrations :: Definition MigrationsSchemas MigrationsSchemas

283+createMigrations

284+ :: Has "schema_migrations" schema ('Table MigrationsTable)

285+ => Definition schema schema

345createMigrations =

286createMigrations =

346 createTableIfNotExists #schema_migrations

287 createTableIfNotExists #schema_migrations

347− ( (text & notNullable) `as` #name :*

288+ ( (text & notNull) `As` #name :*

348− (timestampWithTimeZone & notNullable & default_ currentTimestamp)

289+ (timestampWithTimeZone & notNull & default_ currentTimestamp)

349− `as` #executed_at )

290+ `As` #executed_at :* Nil )

350− ( unique #name `as` #migrations_unique_name )

291+ ( unique (#name :* Nil) `As` #migrations_unique_name :* Nil )

351−

292+

352−-- | Inserts a `Migration` into the `MigrationsTable`, returning

293+-- | Inserts a `Migration` into the `MigrationsTable`

353−-- the time at which it was inserted.

294+insertMigration

354−insertMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

295+ :: Has "schema_migrations" schema ('Table MigrationsTable)

296+ => Manipulation schema '[ 'NotNull 'PGtext] '[]

355−insertMigration = insertInto_ #schema_migrations

297+insertMigration = insertRow_ #schema_migrations

298+ ( Set (param @1) `As` #name :*

356− (Values_ (Set (param @1) `as` #name :* Default `as` #executed_at))

299+ Default `As` #executed_at :* Nil )

357−

300+

358−-- | Deletes a `Migration` from the `MigrationsTable`, returning

301+-- | Deletes a `Migration` from the `MigrationsTable`

359−-- the time at which it was inserted.

360−deleteMigration :: Manipulation_ MigrationsSchemas (Only Text) ()

302+deleteMigration

303+ :: Has "schema_migrations" schema ('Table MigrationsTable)

304+ => Manipulation schema '[ 'NotNull 'PGtext ] '[]

361deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)

305deleteMigration = deleteFrom_ #schema_migrations (#name .== param @1)

362

306

363-- | Selects a `Migration` from the `MigrationsTable`, returning

307-- | Selects a `Migration` from the `MigrationsTable`, returning

364−-- the time at which it was inserted.

308+-- the time at which it was executed.

365selectMigration

309selectMigration

366− :: Query_ MigrationsSchemas (Only Text) (Only UTCTime)

310+ :: Has "schema_migrations" schema ('Table MigrationsTable)

311+ => Query schema '[ 'NotNull 'PGtext ]

312+ '[ "executed_at" ::: 'NotNull 'PGtimestamptz ]

367−selectMigration = select_ (#executed_at `as` #fromOnly)

313+selectMigration = select

314+ (#executed_at `As` #executed_at :* Nil)

368− $ from (table (#schema_migrations))

315+ ( from (table (#schema_migrations `As` #m))

369− & where_ (#name .== param @1)

316+ & where_ (#name .== param @1))

370−

371−selectMigrations :: Query_ MigrationsSchemas () MigrationRow

372−selectMigrations = select_

373− (#name `as` #migrationName :* #executed_at `as` #migrationTime)

374− (from (table #schema_migrations))

375−

376−data MigrateCommand

377− = MigrateStatus

378− | MigrateUp

379− | MigrateDown deriving (GHC.Generic, Show)

380−

381−{- | `defaultMain` creates a simple executable

382−from a connection string and a list of `Migration`s. -}

383−defaultMain

384− :: Migratory p

385− => ByteString

386− -- ^ connection string

387− -> Path (Migration p) db0 db1

388− -- ^ migrations

389− -> IO ()

390−defaultMain connectTo migrations = do

391− command <- readCommandFromArgs

392− maybe (pure ()) performCommand command

393−

394− where

395−

396− performCommand :: MigrateCommand -> IO ()

397− performCommand = \case

398− MigrateStatus -> withConnection connectTo $

399− suppressNotices >> migrateStatus

400− MigrateUp -> withConnection connectTo $

401− suppressNotices & pqThen (migrateUp migrations) & pqThen migrateStatus

402− MigrateDown -> withConnection connectTo $

403− suppressNotices & pqThen (migrateDown migrations) & pqThen migrateStatus

404−

405− migrateStatus :: PQ schema schema IO ()

406− migrateStatus = unsafePQ $ do

407− runNames <- getRunMigrationNames

408− let names = ctoList name migrations

409− unrunNames = names \\ runNames

410− liftIO $ displayRunned runNames >> displayUnrunned unrunNames

411−

412− suppressNotices :: PQ schema schema IO ()

413− suppressNotices = manipulate_ $

414− UnsafeManipulation "SET client_min_messages TO WARNING;"

415−

416− readCommandFromArgs :: IO (Maybe MigrateCommand)

417− readCommandFromArgs = getArgs >>= \case

418− ["migrate"] -> pure . Just $ MigrateUp

419− ["rollback"] -> pure . Just $ MigrateDown

420− ["status"] -> pure . Just $ MigrateStatus

421− args -> displayUsage args >> pure Nothing

422−

423− displayUsage :: [String] -> IO ()

424− displayUsage args = do

425− putStrLn $ "Invalid command: \"" <> unwords args <> "\". Use:"

426− putStrLn "migrate to run all available migrations"

427− putStrLn "rollback to rollback all available migrations"

428− putStrLn "status to display migrations run and migrations left to run"

429−

430− getRunMigrationNames :: (MonadIO m) => PQ db0 db0 m [Text]

431− getRunMigrationNames =

432− fmap migrationName <$> (unsafePQ (define createMigrations & pqThen (runQuery selectMigrations)) >>= getRows)

433−

434− displayListOfNames :: [Text] -> IO ()

435− displayListOfNames [] = Text.putStrLn " None"

436− displayListOfNames xs =

437− let singleName n = Text.putStrLn $ " - " <> n

438− in traverse_ singleName xs

439−

440− displayUnrunned :: [Text] -> IO ()

441− displayUnrunned unrunned =

442− Text.putStrLn "Migrations left to run:"

443− >> displayListOfNames unrunned

444−

445− displayRunned :: [Text] -> IO ()

446− displayRunned runned =

447− Text.putStrLn "Migrations already run:"

448− >> displayListOfNames runned

squeal-postgresql/src/Squeal/PostgreSQL/PG.hsdeleted−388

@@ -1,388 +0,0 @@

1−{-|

2−Module: Squeal.PostgreSQL.PG

3−Description: Embedding of Haskell types into Postgres's type system

4−Copyright: (c) Eitan Chatav, 2010

5−Maintainer: eitan@morphism.tech

6−Stability: experimental

7−

8−`Squeal.PostgreSQL.PG` provides type families for turning Haskell

9−`Type`s into corresponding Postgres types.

10−-}

11−{-# LANGUAGE

12− AllowAmbiguousTypes

13− , DeriveAnyClass

14− , DeriveFoldable

15− , DeriveFunctor

16− , DeriveGeneric

17− , DeriveTraversable

18− , DerivingStrategies

19− , DefaultSignatures

20− , FlexibleContexts

21− , FlexibleInstances

22− , FunctionalDependencies

23− , GADTs

24− , LambdaCase

25− , MultiParamTypeClasses

26− , OverloadedStrings

27− , ScopedTypeVariables

28− , TypeApplications

29− , TypeFamilies

30− , TypeInType

31− , TypeOperators

32− , UndecidableInstances

33− , UndecidableSuperClasses

34−#-}

35−

36−module Squeal.PostgreSQL.PG

37− ( -- * PG embeddings

38− PG

39− , NullPG

40− , TuplePG

41− , RowPG

42− -- * Storage newtypes

43− , Money (..)

44− , Json (..)

45− , Jsonb (..)

46− , Composite (..)

47− , Enumerated (..)

48− , VarArray (..)

49− , FixArray (..)

50− , LibPQ.Oid (..)

51− -- * Type families

52− , LabelsPG

53− , DimPG

54− , FixPG

55− , TupleOf

56− , TupleCodeOf

57− , RowOf

58− , ConstructorsOf

59− , ConstructorNameOf

60− , ConstructorNamesOf

61− ) where

62−

63−import Data.Aeson (Value)

64−import Data.Kind (Type)

65−import Data.Int (Int16, Int32, Int64)

66−import Data.Scientific (Scientific)

67−import Data.Time (Day, DiffTime, LocalTime, TimeOfDay, TimeZone, UTCTime)

68−import Data.Vector (Vector)

69−import Data.UUID.Types (UUID)

70−import GHC.TypeLits

71−import Network.IP.Addr (NetAddr, IP)

72−

73−import qualified Data.ByteString.Lazy as Lazy (ByteString)

74−import qualified Data.ByteString as Strict (ByteString)

75−import qualified Data.Text.Lazy as Lazy (Text)

76−import qualified Data.Text as Strict (Text)

77−import qualified Database.PostgreSQL.LibPQ as LibPQ

78−import qualified GHC.Generics as GHC

79−import qualified Generics.SOP as SOP

80−import qualified Generics.SOP.Record as SOP

81−import qualified Generics.SOP.Type.Metadata as Type

82−

83−import Squeal.PostgreSQL.Alias

84−import Squeal.PostgreSQL.Schema

85−

86−-- $setup

87−-- >>> import Squeal.PostgreSQL

88−-- >>> import Data.Text (Text)

89−

90−{- | The `PG` type family embeds a subset of Haskell types

91−as Postgres types. As an open type family, `PG` is extensible.

92−

93−>>> :kind! PG LocalTime

94−PG LocalTime :: PGType

95−= 'PGtimestamp

96−

97−>>> newtype MyDouble = My Double

98−>>> :set -XTypeFamilies

99−>>> type instance PG MyDouble = 'PGfloat8

100−-}

101−type family PG (hask :: Type) :: PGType

102−-- | `PGbool`

103−type instance PG Bool = 'PGbool

104−-- | `PGint2`

105−type instance PG Int16 = 'PGint2

106−-- | `PGint4`

107−type instance PG Int32 = 'PGint4

108−-- | `PGint8`

109−type instance PG Int64 = 'PGint8

110−-- | `PGint2`

111−type instance PG LibPQ.Oid = 'PGoid

112−-- | `PGnumeric`

113−type instance PG Scientific = 'PGnumeric

114−-- | `PGfloat4`

115−type instance PG Float = 'PGfloat4

116−-- | `PGfloat8`

117−type instance PG Double = 'PGfloat8

118−-- | `PGchar` @1@

119−type instance PG Char = 'PGchar 1

120−-- | `PGtext`

121−type instance PG Strict.Text = 'PGtext

122−-- | `PGtext`

123−type instance PG Lazy.Text = 'PGtext

124−-- | `PGtext`

125−type instance PG String = 'PGtext

126−-- | `PGbytea`

127−type instance PG Strict.ByteString = 'PGbytea

128−-- | `PGbytea`

129−type instance PG Lazy.ByteString = 'PGbytea

130−-- | `PGtimestamp`

131−type instance PG LocalTime = 'PGtimestamp

132−-- | `PGtimestamptz`

133−type instance PG UTCTime = 'PGtimestamptz

134−-- | `PGdate`

135−type instance PG Day = 'PGdate

136−-- | `PGtime`

137−type instance PG TimeOfDay = 'PGtime

138−-- | `PGtimetz`

139−type instance PG (TimeOfDay, TimeZone) = 'PGtimetz

140−-- | `PGinterval`

141−type instance PG DiffTime = 'PGinterval

142−-- | `PGuuid`

143−type instance PG UUID = 'PGuuid

144−-- | `PGinet`

145−type instance PG (NetAddr IP) = 'PGinet

146−-- | `PGjson`

147−type instance PG Value = 'PGjson

148−

149−{-| The `LabelsPG` type family calculates the constructors of a

150−Haskell enum type.

151−

152−>>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic

153−>>> instance SOP.Generic Schwarma

154−>>> instance SOP.HasDatatypeInfo Schwarma

155−>>> :kind! LabelsPG Schwarma

156−LabelsPG Schwarma :: [Type.ConstructorName]

157−= '["Beef", "Lamb", "Chicken"]

158−-}

159−type family LabelsPG (hask :: Type) :: [Type.ConstructorName] where

160− LabelsPG hask =

161− ConstructorNamesOf (ConstructorsOf (SOP.DatatypeInfoOf hask))

162−

163−{- |

164−`RowPG` turns a Haskell `Type` into a `RowType`.

165−

166−`RowPG` may be applied to normal Haskell record types provided they

167−have `SOP.Generic` and `SOP.HasDatatypeInfo` instances;

168−

169−>>> data Person = Person { name :: Strict.Text, age :: Int32 } deriving GHC.Generic

170−>>> instance SOP.Generic Person

171−>>> instance SOP.HasDatatypeInfo Person

172−>>> :kind! RowPG Person

173−RowPG Person :: [(Symbol, NullityType)]

174−= '["name" ::: 'NotNull 'PGtext, "age" ::: 'NotNull 'PGint4]

175−-}

176−type family RowPG (hask :: Type) :: RowType where

177− RowPG hask = RowOf (SOP.RecordCodeOf hask)

178−

179−-- | `RowOf` applies `NullPG` to the fields of a list.

180−type family RowOf (record :: [(Symbol, Type)]) :: RowType where

181− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': col4 ::: ty4 ': record) =

182− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': col4 ::: NullPG ty4 ': RowOf record

183− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': col3 ::: ty3 ': record) =

184− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': col3 ::: NullPG ty3 ': RowOf record

185− RowOf (col ::: ty ': col1 ::: ty1 ': col2 ::: ty2 ': record) =

186− col ::: NullPG ty ': col1 ::: NullPG ty1 ': col2 ::: NullPG ty2 ': RowOf record

187− RowOf (col ::: ty ': col1 ::: ty1 ': record) =

188− col ::: NullPG ty ': col1::: NullPG ty1 ': RowOf record

189− RowOf (col ::: ty ': record) = col ::: NullPG ty ': RowOf record

190− RowOf '[] = '[]

191−

192−{- | `NullPG` turns a Haskell type into a `NullityType`.

193−

194−>>> :kind! NullPG Double

195−NullPG Double :: NullityType

196−= 'NotNull 'PGfloat8

197−>>> :kind! NullPG (Maybe Double)

198−NullPG (Maybe Double) :: NullityType

199−= 'Null 'PGfloat8

200−-}

201−type family NullPG (hask :: Type) :: NullityType where

202− NullPG (Maybe hask) = 'Null (PG hask)

203− NullPG hask = 'NotNull (PG hask)

204−

205−{- | `TuplePG` turns a Haskell tuple type (including record types) into

206−the corresponding list of `NullityType`s.

207−

208−>>> :kind! TuplePG (Double, Maybe Char)

209−TuplePG (Double, Maybe Char) :: [NullityType]

210−= '[ 'NotNull 'PGfloat8, 'Null ('PGchar 1)]

211−-}

212−type family TuplePG (hask :: Type) :: [NullityType] where

213− TuplePG hask = TupleOf (TupleCodeOf hask (SOP.Code hask))

214−

215−-- | `TupleOf` turns a list of Haskell `Type`s into a list of `NullityType`s.

216−type family TupleOf (tuple :: [Type]) :: [NullityType] where

217− TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': hask5 ': tuple) =

218− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': NullPG hask5 ': TupleOf tuple

219− TupleOf (hask ': hask1 ': hask2 ': hask3 ': hask4 ': tuple) =

220− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': NullPG hask4 ': TupleOf tuple

221− TupleOf (hask ': hask1 ': hask2 ': hask3 ': tuple) =

222− NullPG hask ': NullPG hask1 ': NullPG hask2 ': NullPG hask3 ': TupleOf tuple

223− TupleOf (hask ': hask1 ': hask2 ': tuple) =

224− NullPG hask ': NullPG hask1 ': NullPG hask2 ': TupleOf tuple

225− TupleOf (hask ': hask1 ': tuple) = NullPG hask ': NullPG hask1 ': TupleOf tuple

226− TupleOf (hask ': tuple) = NullPG hask ': TupleOf tuple

227− TupleOf '[] = '[]

228−

229−-- | `TupleCodeOf` takes the `SOP.Code` of a haskell `Type`

230−-- and if it's a simple product returns it, otherwise giving a `TypeError`.

231−type family TupleCodeOf (hask :: Type) (code :: [[Type]]) :: [Type] where

232− TupleCodeOf hask '[tuple] = tuple

233− TupleCodeOf hask '[] =

234− TypeError

235− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

236− ':$$: 'Text "It is a void type with no constructors."

237− )

238− TupleCodeOf hask (_ ': _ ': _) =

239− TypeError

240− ( 'Text "The type `" ':<>: 'ShowType hask ':<>: 'Text "' is not a tuple type."

241− ':$$: 'Text "It is a sum type with more than one constructor."

242− )

243−

244−-- | Calculates constructors of a datatype.

245−type family ConstructorsOf (datatype :: Type.DatatypeInfo)

246− :: [Type.ConstructorInfo] where

247− ConstructorsOf ('Type.ADT _module _datatype constructors) =

248− constructors

249− ConstructorsOf ('Type.Newtype _module _datatype constructor) =

250− '[constructor]

251−

252−-- | Calculates the name of a nullary constructor, otherwise

253−-- generates a type error.

254−type family ConstructorNameOf (constructor :: Type.ConstructorInfo)

255− :: Type.ConstructorName where

256− ConstructorNameOf ('Type.Constructor name) = name

257− ConstructorNameOf ('Type.Infix name _assoc _fix) = TypeError

258− ('Text "ConstructorNameOf error: non-nullary constructor "

259− ':<>: 'Text name)

260− ConstructorNameOf ('Type.Record name _fields) = TypeError

261− ('Text "ConstructorNameOf error: non-nullary constructor "

262− ':<>: 'Text name)

263−

264−-- | Calculate the names of nullary constructors.

265−type family ConstructorNamesOf (constructors :: [Type.ConstructorInfo])

266− :: [Type.ConstructorName] where

267− ConstructorNamesOf '[] = '[]

268− ConstructorNamesOf (constructor ': constructors) =

269− ConstructorNameOf constructor ': ConstructorNamesOf constructors

270−

271−-- | `DimPG` turns Haskell nested homogeneous tuples into a list of lengths.

272−type family DimPG (hask :: Type) :: [Nat] where

273− DimPG (x,x) = 2 ': DimPG x

274− DimPG (x,x,x) = 3 ': DimPG x

275− DimPG (x,x,x,x) = 4 ': DimPG x

276− DimPG (x,x,x,x,x) = 5 ': DimPG x

277− DimPG (x,x,x,x,x,x) = 6 ': DimPG x

278− DimPG (x,x,x,x,x,x,x) = 7 ': DimPG x

279− DimPG (x,x,x,x,x,x,x,x) = 8 ': DimPG x

280− DimPG (x,x,x,x,x,x,x,x,x) = 9 ': DimPG x

281− DimPG (x,x,x,x,x,x,x,x,x,x) = 10 ': DimPG x

282− DimPG x = '[]

283−

284−-- | `FixPG` extracts `NullPG` of the base type of nested homogeneous tuples.

285−type family FixPG (hask :: Type) :: NullityType where

286− FixPG (x,x) = FixPG x

287− FixPG (x,x,x) = FixPG x

288− FixPG (x,x,x,x) = FixPG x

289− FixPG (x,x,x,x,x) = FixPG x

290− FixPG (x,x,x,x,x,x) = FixPG x

291− FixPG (x,x,x,x,x,x,x) = FixPG x

292− FixPG (x,x,x,x,x,x,x,x) = FixPG x

293− FixPG (x,x,x,x,x,x,x,x,x) = FixPG x

294− FixPG (x,x,x,x,x,x,x,x,x,x) = FixPG x

295− FixPG (x,x,x,x,x,x,x,x,x,x,x) = FixPG x

296− FixPG x = NullPG x

297−

298−{- | The `Money` newtype stores a monetary value in terms

299−of the number of cents, i.e. @$2,000.20@ would be expressed as

300−@Money { cents = 200020 }@.

301−

302−>>> import Control.Monad (void)

303−>>> import Control.Monad.IO.Class (liftIO)

304−>>> import Squeal.PostgreSQL

305−>>> :{

306−let

307− roundTrip :: Query_ (Public '[]) (Only Money) (Only Money)

308− roundTrip = values_ $ parameter @1 money `as` #fromOnly

309−:}

310−

311−>>> let input = Only (Money 20020)

312−

313−>>> :{

314−withConnection "host=localhost port=5432 dbname=exampledb" $ do

315− result <- runQueryParams roundTrip input

316− Just output <- firstRow result

317− liftIO . print $ input == output

318−:}

319−True

320−-}

321−newtype Money = Money { cents :: Int64 }

322− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

323− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

324−-- | `PGmoney`

325−type instance PG Money = 'PGmoney

326−

327−{- | The `Json` newtype is an indication that the Haskell

328−type it's applied to should be stored as a `PGjson`.

329−-}

330−newtype Json hask = Json {getJson :: hask}

331− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

332− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

333−-- | `PGjson`

334−type instance PG (Json hask) = 'PGjson

335−

336−{- | The `Jsonb` newtype is an indication that the Haskell

337−type it's applied to should be stored as a `PGjsonb`.

338−-}

339−newtype Jsonb hask = Jsonb {getJsonb :: hask}

340− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

341− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

342−-- | `PGjsonb`

343−type instance PG (Jsonb hask) = 'PGjsonb

344−

345−{- | The `Composite` newtype is an indication that the Haskell

346−type it's applied to should be stored as a `PGcomposite`.

347−-}

348−newtype Composite record = Composite {getComposite :: record}

349− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

350− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

351−-- | `PGcomposite` @(@`RowPG` @hask)@

352−type instance PG (Composite hask) = 'PGcomposite (RowPG hask)

353−

354−{- | The `Enumerated` newtype is an indication that the Haskell

355−type it's applied to should be stored as a `PGenum`.

356−-}

357−newtype Enumerated enum = Enumerated {getEnumerated :: enum}

358− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

359− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

360−-- | `PGenum` @(@`LabelsPG` @hask)@

361−type instance PG (Enumerated hask) = 'PGenum (LabelsPG hask)

362−

363−{- | The `VarArray` newtype is an indication that the Haskell

364−type it's applied to should be stored as a `PGvararray`.

365−

366−>>> :kind! PG (VarArray (Vector Double))

367−PG (VarArray (Vector Double)) :: PGType

368−= 'PGvararray ('NotNull 'PGfloat8)

369−-}

370−newtype VarArray arr = VarArray {getVarArray :: arr}

371− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

372− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

373−-- | `PGvararray` @(@`NullPG` @hask)@

374−type instance PG (VarArray (Vector hask)) = 'PGvararray (NullPG hask)

375−type instance PG (VarArray [hask]) = 'PGvararray (NullPG hask)

376−

377−{- | The `FixArray` newtype is an indication that the Haskell

378−type it's applied to should be stored as a `PGfixarray`.

379−

380−>>> :kind! PG (FixArray ((Double, Double), (Double, Double)))

381−PG (FixArray ((Double, Double), (Double, Double))) :: PGType

382−= 'PGfixarray '[2, 2] ('NotNull 'PGfloat8)

383−-}

384−newtype FixArray arr = FixArray {getFixArray :: arr}

385− deriving stock (Eq, Ord, Show, Read, GHC.Generic)

386− deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)

387−-- | `PGfixarray` @(@`DimPG` @hask) (@`FixPG` @hask)@

388−type instance PG (FixArray hask) = 'PGfixarray (DimPG hask) (FixPG hask)

squeal-postgresql/src/Squeal/PostgreSQL/PQ.hs+211−313

@@ -6,12 +6,12 @@ Maintainer: eitan@morphism.tech

6Stability: experimental

8This module is where Squeal commands actually get executed by

9−`Database.PostgreSQL.LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing

9+`LibPQ`. It containts two typeclasses, `IndexedMonadTransPQ` for executing

10a `Definition` and `MonadPQ` for executing a `Manipulation` or `Query`,

11and a `PQ` type with instances for them.

13Using Squeal in your application will come down to defining

14−the @schemas@ of your database and including @PQ schemas schemas@ in your

14+the @schema@ of your database and including @PQ schema schema@ in your

15application's monad transformer stack, giving it an instance of `MonadPQ`.

17This module also provides functions for retrieving rows from the `LibPQ.Result`

@@ -24,7 +24,6 @@ of executing Squeal commands.

24 , FunctionalDependencies

25 , FlexibleContexts

26 , FlexibleInstances

27− , InstanceSigs

28 , OverloadedStrings

27 , OverloadedStrings

29 , RankNTypes

28 , RankNTypes

30 , ScopedTypeVariables

29 , ScopedTypeVariables

@@ -49,7 +48,9 @@ module Squeal.PostgreSQL.PQ

49 , evalPQ

48 , evalPQ

50 , IndexedMonadTransPQ (..)

49 , IndexedMonadTransPQ (..)

51 , MonadPQ (..)

50 , MonadPQ (..)

52− -- * Results

51+ , PQRun

52+ , pqliftWith

53+ -- * Result

53 , LibPQ.Result

54 , LibPQ.Result

54 , LibPQ.Row

55 , LibPQ.Row

55 , ntuples

56 , ntuples

@@ -61,33 +62,22 @@ module Squeal.PostgreSQL.PQ

61 , LibPQ.ExecStatus (..)

62 , LibPQ.ExecStatus (..)

62 , resultStatus

63 , resultStatus

63 , resultErrorMessage

64 , resultErrorMessage

64− , resultErrorCode

65− -- * Exceptions

66− , SquealException (..)

67− , PQState (..)

68− , okResult

69− , catchSqueal

70− , handleSqueal

71− , trySqueal

72 ) where

65 ) where

74−import Control.Exception (Exception, throw)

67+import Control.Exception.Lifted

68+import Control.Monad.Base

75import Control.Monad.Except

69import Control.Monad.Except

76import Control.Monad.Morph

70import Control.Monad.Morph

77−import UnliftIO (MonadUnliftIO (..), bracket, catch, handle, try)

71+import Control.Monad.Trans.Control

78import Data.ByteString (ByteString)

72import Data.ByteString (ByteString)

79import Data.Foldable

73import Data.Foldable

80import Data.Function ((&))

74import Data.Function ((&))

81−import Data.Functor ((<&>))

82import Data.Kind

75import Data.Kind

83−import Data.Text (pack, Text)

76+import Data.Monoid

84import Data.Traversable

77import Data.Traversable

85import Generics.SOP

78import Generics.SOP

86−import PostgreSQL.Binary.Encoding (encodingBytes)

88−import qualified Control.Monad.Fail as Fail

89import qualified Database.PostgreSQL.LibPQ as LibPQ

80import qualified Database.PostgreSQL.LibPQ as LibPQ

90−import qualified PostgreSQL.Binary.Encoding as Encoding

92import Squeal.PostgreSQL.Binary

82import Squeal.PostgreSQL.Binary

93import Squeal.PostgreSQL.Definition

83import Squeal.PostgreSQL.Definition

@@ -100,6 +90,7 @@ import Control.Monad.Trans.Identity

100import Control.Monad.Trans.Reader

90import Control.Monad.Trans.Reader

101import Control.Monad.Trans.Maybe

91import Control.Monad.Trans.Maybe

102import Control.Monad.Trans.Cont

92import Control.Monad.Trans.Cont

93+import Control.Monad.Trans.List

103

104import qualified Control.Monad.Trans.State.Lazy as Lazy

95import qualified Control.Monad.Trans.State.Lazy as Lazy

105import qualified Control.Monad.Trans.State.Strict as Strict

96import qualified Control.Monad.Trans.State.Strict as Strict

@@ -108,9 +99,6 @@ import qualified Control.Monad.Trans.Writer.Strict as Strict

108import qualified Control.Monad.Trans.RWS.Lazy as Lazy

99import qualified Control.Monad.Trans.RWS.Lazy as Lazy

109import qualified Control.Monad.Trans.RWS.Strict as Strict

100import qualified Control.Monad.Trans.RWS.Strict as Strict

110

101

111−-- $setup

112−-- >>> import Squeal.PostgreSQL

113−

114{- | Makes a new connection to the database server.

102{- | Makes a new connection to the database server.

115

103

116This function opens a new database connection using the parameters taken

104This function opens a new database connection using the parameters taken

@@ -137,22 +125,22 @@ Note that, for now, squeal doesn't offer any protection from connecting

137with the wrong schema!

125with the wrong schema!

138-}

126-}

139connectdb

127connectdb

140− :: forall schemas io

128+ :: forall schema io

141− . MonadIO io

129+ . MonadBase IO io

142 => ByteString -- ^ conninfo

130 => ByteString -- ^ conninfo

143− -> io (K LibPQ.Connection schemas)

131+ -> io (K LibPQ.Connection schema)

144−connectdb = fmap K . liftIO . LibPQ.connectdb

132+connectdb = fmap K . liftBase . LibPQ.connectdb

145

133

146-- | Closes the connection to the server.

134-- | Closes the connection to the server.

147−finish :: MonadIO io => K LibPQ.Connection schemas -> io ()

135+finish :: MonadBase IO io => K LibPQ.Connection schema -> io ()

148−finish = liftIO . LibPQ.finish . unK

136+finish = liftBase . LibPQ.finish . unK

149

137

150-- | Do `connectdb` and `finish` before and after a computation.

138-- | Do `connectdb` and `finish` before and after a computation.

151withConnection

139withConnection

152− :: forall schemas0 schemas1 io x

140+ :: forall schema0 schema1 io x

153− . MonadUnliftIO io

141+ . MonadBaseControl IO io

154 => ByteString

142 => ByteString

155− -> PQ schemas0 schemas1 io x

143+ -> PQ schema0 schema1 io x

156 -> io x

144 -> io x

157withConnection connString action = do

145withConnection connString action = do

158 K x <- bracket (connectdb connString) finish (unPQ action)

146 K x <- bracket (connectdb connString) finish (unPQ action)

@@ -160,47 +148,47 @@ withConnection connString action = do

160

148

161-- | Safely `lowerConnection` to a smaller schema.

149-- | Safely `lowerConnection` to a smaller schema.

162lowerConnection

150lowerConnection

163− :: K LibPQ.Connection (schema ': schemas)

151+ :: K LibPQ.Connection (table ': schema)

164− -> K LibPQ.Connection schemas

152+ -> K LibPQ.Connection schema

165lowerConnection (K conn) = K conn

153lowerConnection (K conn) = K conn

166

154

167-- | We keep track of the schema via an Atkey indexed state monad transformer,

155-- | We keep track of the schema via an Atkey indexed state monad transformer,

168-- `PQ`.

156-- `PQ`.

169newtype PQ

157newtype PQ

170− (schemas0 :: SchemasType)

158+ (schema0 :: SchemaType)

171− (schemas1 :: SchemasType)

159+ (schema1 :: SchemaType)

172 (m :: Type -> Type)

160 (m :: Type -> Type)

173 (x :: Type) =

161 (x :: Type) =

174− PQ { unPQ :: K LibPQ.Connection schemas0 -> m (K x schemas1) }

162+ PQ { unPQ :: K LibPQ.Connection schema0 -> m (K x schema1) }

175

163

176−instance Monad m => Functor (PQ schemas0 schemas1 m) where

164+instance Monad m => Functor (PQ schema0 schema1 m) where

177 fmap f (PQ pq) = PQ $ \ conn -> do

165 fmap f (PQ pq) = PQ $ \ conn -> do

178 K x <- pq conn

166 K x <- pq conn

179 return $ K (f x)

167 return $ K (f x)

180

168

181−-- | Run a `PQ` and keep the result and the `LibPQ.Connection`.

169+-- | Run a `PQ` and keep the result and the `Connection`.

182runPQ

170runPQ

183 :: Functor m

171 :: Functor m

184− => PQ schemas0 schemas1 m x

172+ => PQ schema0 schema1 m x

185− -> K LibPQ.Connection schemas0

173+ -> K LibPQ.Connection schema0

186− -> m (x, K LibPQ.Connection schemas1)

174+ -> m (x, K LibPQ.Connection schema1)

187runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn

175runPQ (PQ pq) conn = (\ x -> (unK x, K (unK conn))) <$> pq conn

188 -- K x <- pq conn

176 -- K x <- pq conn

189 -- return (x, K (unK conn))

177 -- return (x, K (unK conn))

190

178

191−-- | Execute a `PQ` and discard the result but keep the `LibPQ.Connection`.

179+-- | Execute a `PQ` and discard the result but keep the `Connection`.

192execPQ

180execPQ

193 :: Functor m

181 :: Functor m

194− => PQ schemas0 schemas1 m x

182+ => PQ schema0 schema1 m x

195− -> K LibPQ.Connection schemas0

183+ -> K LibPQ.Connection schema0

196− -> m (K LibPQ.Connection schemas1)

184+ -> m (K LibPQ.Connection schema1)

197execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn

185execPQ (PQ pq) conn = mapKK (\ _ -> unK conn) <$> pq conn

198

186

199−-- | Evaluate a `PQ` and discard the `LibPQ.Connection` but keep the result.

187+-- | Evaluate a `PQ` and discard the `Connection` but keep the result.

200evalPQ

188evalPQ

201 :: Functor m

189 :: Functor m

202− => PQ schemas0 schemas1 m x

190+ => PQ schema0 schema1 m x

203− -> K LibPQ.Connection schemas0

191+ -> K LibPQ.Connection schema0

204 -> m x

192 -> m x

205evalPQ (PQ pq) conn = unK <$> pq conn

193evalPQ (PQ pq) conn = unK <$> pq conn

206

194

@@ -208,56 +196,60 @@ evalPQ (PQ pq) conn = unK <$> pq conn

208-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).

196-- [enriched category](https://ncatlab.org/nlab/show/enriched+category).

209-- An indexed monad transformer transforms a `Monad` into an indexed monad.

197-- An indexed monad transformer transforms a `Monad` into an indexed monad.

210-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that

198-- And, `IndexedMonadTransPQ` is a class for indexed monad transformers that

211−-- support running `Definition`s using `define`.

199+-- support running `Definition`s using `define` and embedding a computation

200+-- in a larger schema using `pqEmbed`.

212class IndexedMonadTransPQ pq where

201class IndexedMonadTransPQ pq where

213

202

214 -- | indexed analog of `<*>`

203 -- | indexed analog of `<*>`

215 pqAp

204 pqAp

216 :: Monad m

205 :: Monad m

217− => pq schemas0 schemas1 m (x -> y)

206+ => pq schema0 schema1 m (x -> y)

218− -> pq schemas1 schemas2 m x

207+ -> pq schema1 schema2 m x

219− -> pq schemas0 schemas2 m y

208+ -> pq schema0 schema2 m y

220

209

221 -- | indexed analog of `join`

210 -- | indexed analog of `join`

222 pqJoin

211 pqJoin

223 :: Monad m

212 :: Monad m

224− => pq schemas0 schemas1 m (pq schemas1 schemas2 m y)

213+ => pq schema0 schema1 m (pq schema1 schema2 m y)

225− -> pq schemas0 schemas2 m y

214+ -> pq schema0 schema2 m y

226 pqJoin pq = pq & pqBind id

215 pqJoin pq = pq & pqBind id

227

216

228 -- | indexed analog of `=<<`

217 -- | indexed analog of `=<<`

229 pqBind

218 pqBind

230 :: Monad m

219 :: Monad m

231− => (x -> pq schemas1 schemas2 m y)

220+ => (x -> pq schema1 schema2 m y)

232− -> pq schemas0 schemas1 m x

221+ -> pq schema0 schema1 m x

233− -> pq schemas0 schemas2 m y

222+ -> pq schema0 schema2 m y

234

223

235 -- | indexed analog of flipped `>>`

224 -- | indexed analog of flipped `>>`

236 pqThen

225 pqThen

237 :: Monad m

226 :: Monad m

238− => pq schemas1 schemas2 m y

227+ => pq schema1 schema2 m y

239− -> pq schemas0 schemas1 m x

228+ -> pq schema0 schema1 m x

240− -> pq schemas0 schemas2 m y

229+ -> pq schema0 schema2 m y

241 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)

230 pqThen pq2 pq1 = pq1 & pqBind (\ _ -> pq2)

242

231

243 -- | indexed analog of `<=<`

232 -- | indexed analog of `<=<`

244 pqAndThen

233 pqAndThen

245 :: Monad m

234 :: Monad m

246− => (y -> pq schemas1 schemas2 m z)

235+ => (y -> pq schema1 schema2 m z)

247− -> (x -> pq schemas0 schemas1 m y)

236+ -> (x -> pq schema0 schema1 m y)

248− -> x -> pq schemas0 schemas2 m z

237+ -> x -> pq schema0 schema2 m z

249 pqAndThen g f x = pqBind g (f x)

238 pqAndThen g f x = pqBind g (f x)

250

239

240+ -- | Safely embed a computation in a larger schema.

241+ pqEmbed

242+ :: Monad m

243+ => pq schema0 schema1 m x

244+ -> pq (table ': schema0) (table : schema1) m x

245+

251− -- | Run a `Definition` with `LibPQ.exec`.

246+ -- | Run a `Definition` with `LibPQ.exec`, we expect that libpq obeys the law

252− --

253− -- It should be functorial in effect.

254 --

247 --

255− -- @define id = return ()@

256− -- @define (statement1 >>> statement2) = define statement1 & pqThen (define statement2)@

248+ -- @define statement1 & pqThen (define statement2) = define (statement1 >>> statement2)@

257 define

249 define

258− :: MonadIO io

250+ :: MonadBase IO io

259− => Definition schemas0 schemas1

251+ => Definition schema0 schema1

260− -> pq schemas0 schemas1 io ()

252+ -> pq schema0 schema1 io (K LibPQ.Result '[])

261

253

262instance IndexedMonadTransPQ PQ where

254instance IndexedMonadTransPQ PQ where

263

255

@@ -270,26 +262,26 @@ instance IndexedMonadTransPQ PQ where

270 K x' <- x conn

262 K x' <- x conn

271 unPQ (f x') (K (unK conn))

263 unPQ (f x') (K (unK conn))

272

264

265+ pqEmbed (PQ pq) = PQ $ \ (K conn) -> do

266+ K x <- pq (K conn)

267+ return $ K x

268+

273 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do

269 define (UnsafeDefinition q) = PQ $ \ (K conn) -> do

274− resultMaybe <- liftIO $ LibPQ.exec conn q

270+ resultMaybe <- liftBase $ LibPQ.exec conn q

275 case resultMaybe of

271 case resultMaybe of

276− Nothing -> throw $ ResultException

272+ Nothing -> error

277 "define: LibPQ.exec returned no results"

273 "define: LibPQ.exec returned no results"

278− Just result -> K <$> okResult_ result

274+ Just result -> return $ K (K result)

279

275

280−{- | `MonadPQ` is an @mtl@ style constraint, similar to

276+{- | `MonadPQ` is an `mtl` style constraint, similar to

281−`Control.Monad.State.Class.MonadState`, for using `Database.PostgreSQL.LibPQ` to

277+`Control.Monad.State.Class.MonadState`, for using `LibPQ` to

282

278

283* `manipulateParams` runs a `Manipulation` with params from a type

279* `manipulateParams` runs a `Manipulation` with params from a type

284 with a `ToParams` constraint. It calls `LibPQ.execParams` and

280 with a `ToParams` constraint. It calls `LibPQ.execParams` and

285 doesn't afraid of anything.

281 doesn't afraid of anything.

286

282

287−* `manipulateParams_` is like `manipulateParams` for a returning-free statement.

288−

289* `manipulate` is like `manipulateParams` for a parameter-free statement.

283* `manipulate` is like `manipulateParams` for a parameter-free statement.

290

284

291−* `manipulate_` is like `manipulate` for a returning-free statement.

292−

293* `runQueryParams` is like `manipulateParams` for query statements.

285* `runQueryParams` is like `manipulateParams` for query statements.

294

286

295* `runQuery` is like `runQueryParams` for a parameter-free statement.

287* `runQuery` is like `runQueryParams` for a parameter-free statement.

@@ -303,11 +295,11 @@ instance IndexedMonadTransPQ PQ where

303* `forPrepared` is a flipped `traversePrepared`

295* `forPrepared` is a flipped `traversePrepared`

304

296

305* `traversePrepared_` is like `traversePrepared` but works on `Foldable`

297* `traversePrepared_` is like `traversePrepared` but works on `Foldable`

306− containers for a returning-free statement.

298+ containers and returns unit.

307

299

308* `forPrepared_` is a flipped `traversePrepared_`.

300* `forPrepared_` is a flipped `traversePrepared_`.

309

301

310−* `liftPQ` lets you lift actions from `Database.PostgreSQL.LibPQ` that require a connection

302+* `liftPQ` lets you lift actions from `LibPQ` that require a connection

311 into your monad.

303 into your monad.

312

304

313To define an instance, you can minimally define only `manipulateParams`,

305To define an instance, you can minimally define only `manipulateParams`,

@@ -315,398 +307,304 @@ To define an instance, you can minimally define only `manipulateParams`,

315a default instance.

307a default instance.

316

308

317-}

309-}

318−class Monad pq => MonadPQ schemas pq | pq -> schemas where

310+class Monad pq => MonadPQ schema pq | pq -> schema where

319 manipulateParams

311 manipulateParams

320− :: (ToParams x params, All OidOfParam params)

312+ :: ToParams x params

321− => Manipulation '[] schemas params ys

313+ => Manipulation schema params ys

322− -- ^ `insertInto`, `update` or `deleteFrom`

314+ -- ^ `insertRows`, `update` or `deleteFrom`

323 -> x -> pq (K LibPQ.Result ys)

315 -> x -> pq (K LibPQ.Result ys)

324 default manipulateParams

316 default manipulateParams

325− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

317+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

326− => (ToParams x params, All OidOfParam params)

318+ => ToParams x params

327− => Manipulation '[] schemas params ys

319+ => Manipulation schema params ys

328− -- ^ `insertInto`, `update` or `deleteFrom`

320+ -- ^ `insertRows`, `update` or `deleteFrom`

329 -> x -> pq (K LibPQ.Result ys)

321 -> x -> pq (K LibPQ.Result ys)

330 manipulateParams manipulation params = lift $

322 manipulateParams manipulation params = lift $

331 manipulateParams manipulation params

323 manipulateParams manipulation params

332

324

333− manipulateParams_

334− :: (ToParams x params, All OidOfParam params)

335− => Manipulation '[] schemas params '[]

336− -- ^ `insertInto`, `update` or `deleteFrom`

337− -> x -> pq ()

338− manipulateParams_ q x = void $ manipulateParams q x

339−

340− manipulate :: Manipulation '[] schemas '[] ys -> pq (K LibPQ.Result ys)

325+ manipulate :: Manipulation schema '[] ys -> pq (K LibPQ.Result ys)

341 manipulate statement = manipulateParams statement ()

326 manipulate statement = manipulateParams statement ()

342

327

343− manipulate_ :: Manipulation '[] schemas '[] '[] -> pq ()

344− manipulate_ = void . manipulate

345−

346 runQueryParams

328 runQueryParams

347− :: (ToParams x params, All OidOfParam params)

329+ :: ToParams x params

348− => Query '[] '[] schemas params ys

330+ => Query schema params ys

349 -- ^ `select` and friends

331 -- ^ `select` and friends

350 -> x -> pq (K LibPQ.Result ys)

332 -> x -> pq (K LibPQ.Result ys)

351 runQueryParams = manipulateParams . queryStatement

333 runQueryParams = manipulateParams . queryStatement

352

334

353 runQuery

335 runQuery

354− :: Query '[] '[] schemas '[] ys

336+ :: Query schema '[] ys

355 -- ^ `select` and friends

337 -- ^ `select` and friends

356 -> pq (K LibPQ.Result ys)

338 -> pq (K LibPQ.Result ys)

357 runQuery q = runQueryParams q ()

339 runQuery q = runQueryParams q ()

358

340

359 traversePrepared

341 traversePrepared

360− :: (ToParams x params, Traversable list, All OidOfParam params)

342+ :: (ToParams x params, Traversable list)

361− => Manipulation '[] schemas params ys

343+ => Manipulation schema params ys

362− -- ^ `insertInto`, `update`, or `deleteFrom`, and friends

344+ -- ^ `insertRows`, `update`, or `deleteFrom`, and friends

363 -> list x -> pq (list (K LibPQ.Result ys))

345 -> list x -> pq (list (K LibPQ.Result ys))

364 default traversePrepared

346 default traversePrepared

365− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

347+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

366− => (ToParams x params, Traversable list, All OidOfParam params)

348+ => (ToParams x params, Traversable list)

367− => Manipulation '[] schemas params ys -> list x -> pq (list (K LibPQ.Result ys))

349+ => Manipulation schema params ys -> list x -> pq (list (K LibPQ.Result ys))

368 traversePrepared manipulation params = lift $

350 traversePrepared manipulation params = lift $

369 traversePrepared manipulation params

351 traversePrepared manipulation params

370

352

371 forPrepared

353 forPrepared

372− :: (ToParams x params, Traversable list, All OidOfParam params)

354+ :: (ToParams x params, Traversable list)

373 => list x

355 => list x

374− -> Manipulation '[] schemas params ys

356+ -> Manipulation schema params ys

375− -- ^ `insertInto`, `update` or `deleteFrom`

357+ -- ^ `insertRows`, `update` or `deleteFrom`

376 -> pq (list (K LibPQ.Result ys))

358 -> pq (list (K LibPQ.Result ys))

377 forPrepared = flip traversePrepared

359 forPrepared = flip traversePrepared

378

360

379 traversePrepared_

361 traversePrepared_

380− :: (ToParams x params, Foldable list, All OidOfParam params)

362+ :: (ToParams x params, Foldable list)

381− => Manipulation '[] schemas params '[]

363+ => Manipulation schema params '[]

382− -- ^ `insertInto`, `update` or `deleteFrom`

364+ -- ^ `insertRows`, `update` or `deleteFrom`

383 -> list x -> pq ()

365 -> list x -> pq ()

384 default traversePrepared_

366 default traversePrepared_

385− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

367+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

386− => (ToParams x params, Foldable list, All OidOfParam params)

368+ => (ToParams x params, Foldable list)

387− => Manipulation '[] schemas params '[]

369+ => Manipulation schema params '[]

388− -- ^ `insertInto`, `update` or `deleteFrom`

370+ -- ^ `insertRows`, `update` or `deleteFrom`

389 -> list x -> pq ()

371 -> list x -> pq ()

390 traversePrepared_ manipulation params = lift $

372 traversePrepared_ manipulation params = lift $

391 traversePrepared_ manipulation params

373 traversePrepared_ manipulation params

392

374

393 forPrepared_

375 forPrepared_

394− :: (ToParams x params, Foldable list, All OidOfParam params)

376+ :: (ToParams x params, Foldable list)

395 => list x

377 => list x

396− -> Manipulation '[] schemas params '[]

378+ -> Manipulation schema params '[]

397− -- ^ `insertInto`, `update` or `deleteFrom`

379+ -- ^ `insertRows`, `update` or `deleteFrom`

398 -> pq ()

380 -> pq ()

399 forPrepared_ = flip traversePrepared_

381 forPrepared_ = flip traversePrepared_

400

382

401 liftPQ :: (LibPQ.Connection -> IO a) -> pq a

383 liftPQ :: (LibPQ.Connection -> IO a) -> pq a

402 default liftPQ

384 default liftPQ

403− :: (MonadTrans t, MonadPQ schemas pq1, pq ~ t pq1)

385+ :: (MonadTrans t, MonadPQ schema pq1, pq ~ t pq1)

404 => (LibPQ.Connection -> IO a) -> pq a

386 => (LibPQ.Connection -> IO a) -> pq a

405 liftPQ = lift . liftPQ

387 liftPQ = lift . liftPQ

406

388

407−instance (MonadIO io, schemas0 ~ schemas, schemas1 ~ schemas)

389+instance (MonadBase IO io, schema0 ~ schema, schema1 ~ schema)

408− => MonadPQ schemas (PQ schemas0 schemas1 io) where

390+ => MonadPQ schema (PQ schema0 schema1 io) where

409

391

410 manipulateParams

392 manipulateParams

411− (UnsafeManipulation q :: Manipulation '[] schemas ps ys) (params :: x) =

393+ (UnsafeManipulation q :: Manipulation schema ps ys) (params :: x) =

412 PQ $ \ (K conn) -> do

394 PQ $ \ (K conn) -> do

413 let

395 let

414− paramSet

396+ toParam' bytes = (LibPQ.invalidOid,bytes,LibPQ.Binary)

415− :: forall param. OidOfParam param

416− => K (Maybe Encoding.Encoding) param

417− -> K (Maybe (LibPQ.Oid, ByteString, LibPQ.Format)) param

418− paramSet (K maybeEncoding) = K $

419− maybeEncoding <&> \encoding ->

420− (oidOfParam @param, encodingBytes encoding, LibPQ.Binary)

421− params'

422− = hcollapse

423− . hcmap (Proxy @OidOfParam) paramSet

424− $ toParams @x @ps params

397+ params' = fmap (fmap toParam') (hcollapse (toParams @x @ps params))

425− q' = q <> ";"

426− resultMaybe <- liftIO $ LibPQ.execParams conn q' params' LibPQ.Binary

398+ resultMaybe <- liftBase $ LibPQ.execParams conn q params' LibPQ.Binary

427 case resultMaybe of

399 case resultMaybe of

428− Nothing -> throw $ ResultException

400+ Nothing -> error

429 "manipulateParams: LibPQ.execParams returned no results"

401 "manipulateParams: LibPQ.execParams returned no results"

430− Just result -> do

431− okResult_ result

432− return $ K (K result)

402+ Just result -> return $ K (K result)

433

403

434 traversePrepared

404 traversePrepared

435− (UnsafeManipulation q :: Manipulation '[] schemas xs ys) (list :: list x) =

405+ (UnsafeManipulation q :: Manipulation schema xs ys) (list :: list x) =

436− PQ $ \ (K conn) -> liftIO $ do

406+ PQ $ \ (K conn) -> liftBase $ do

437− let

438− temp = "temporary_statement"

407+ let temp = "temporary_statement"

439− paramOid :: forall p. OidOfParam p => K LibPQ.Oid p

440− paramOid = K (oidOfParam @p)

441− paramOids :: NP (K LibPQ.Oid) xs

442− paramOids = hcpure (Proxy @OidOfParam) paramOid

443− paramOids' :: [LibPQ.Oid]

444− paramOids' = hcollapse paramOids

445− prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')

408+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing

446 case prepResultMaybe of

409 case prepResultMaybe of

447− Nothing -> throw $ ResultException

410+ Nothing -> error

448 "traversePrepared: LibPQ.prepare returned no results"

411 "traversePrepared: LibPQ.prepare returned no results"

449− Just prepResult -> okResult_ prepResult

412+ Just prepResult -> do

413+ status <- LibPQ.resultStatus prepResult

414+ unless (status == LibPQ.CommandOk) . error $

415+ "traversePrepared: LibPQ.prepare status " <> show status

450 results <- for list $ \ params -> do

416 results <- for list $ \ params -> do

451 let

417 let

452− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)

418+ toParam' bytes = (bytes,LibPQ.Binary)

453 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))

419 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))

454 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary

420 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary

455 case resultMaybe of

421 case resultMaybe of

456− Nothing -> throw $ ResultException

422+ Nothing -> error

457 "traversePrepared: LibPQ.execParams returned no results"

423 "traversePrepared: LibPQ.execParams returned no results"

458− Just result -> do

459− okResult_ result

460− return $ K result

424+ Just result -> return $ K result

461 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

425 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

462 case deallocResultMaybe of

426 case deallocResultMaybe of

463− Nothing -> throw $ ResultException

427+ Nothing -> error

464 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

428 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

465− Just deallocResult -> okResult_ deallocResult

429+ Just deallocResult -> do

430+ status <- LibPQ.resultStatus deallocResult

431+ unless (status == LibPQ.CommandOk) . error $

432+ "traversePrepared: DEALLOCATE status " <> show status

466 return (K results)

433 return (K results)

467

434

468 traversePrepared_

435 traversePrepared_

469− (UnsafeManipulation q :: Manipulation '[] schemas xs '[]) (list :: list x) =

436+ (UnsafeManipulation q :: Manipulation schema xs '[]) (list :: list x) =

470− PQ $ \ (K conn) -> liftIO $ do

437+ PQ $ \ (K conn) -> liftBase $ do

471− let

472− temp = "temporary_statement"

438+ let temp = "temporary_statement"

473− paramOid :: forall p. OidOfParam p => K LibPQ.Oid p

474− paramOid = K (oidOfParam @p)

475− paramOids :: NP (K LibPQ.Oid) xs

476− paramOids = hcpure (Proxy @OidOfParam) paramOid

477− paramOids' :: [LibPQ.Oid]

478− paramOids' = hcollapse paramOids

479− prepResultMaybe <- LibPQ.prepare conn temp q (Just paramOids')

439+ prepResultMaybe <- LibPQ.prepare conn temp q Nothing

480 case prepResultMaybe of

440 case prepResultMaybe of

481− Nothing -> throw $ ResultException

441+ Nothing -> error

482 "traversePrepared_: LibPQ.prepare returned no results"

442 "traversePrepared_: LibPQ.prepare returned no results"

483− Just prepResult -> okResult_ prepResult

443+ Just prepResult -> do

444+ status <- LibPQ.resultStatus prepResult

445+ unless (status == LibPQ.CommandOk) . error $

446+ "traversePrepared: LibPQ.prepare status " <> show status

484 for_ list $ \ params -> do

447 for_ list $ \ params -> do

485 let

448 let

486− toParam' encoding = (encodingBytes encoding, LibPQ.Binary)

449+ toParam' bytes = (bytes,LibPQ.Binary)

487 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))

450 params' = fmap (fmap toParam') (hcollapse (toParams @x @xs params))

488 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary

451 resultMaybe <- LibPQ.execPrepared conn temp params' LibPQ.Binary

489 case resultMaybe of

452 case resultMaybe of

490− Nothing -> throw $ ResultException

453+ Nothing -> error

491 "traversePrepared_: LibPQ.execParams returned no results"

454 "traversePrepared_: LibPQ.execParams returned no results"

492− Just result -> okResult_ result

455+ Just _result -> return ()

493 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

456 deallocResultMaybe <- LibPQ.exec conn ("DEALLOCATE " <> temp <> ";")

494 case deallocResultMaybe of

457 case deallocResultMaybe of

495− Nothing -> throw $ ResultException

458+ Nothing -> error

496 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

459 "traversePrepared: LibPQ.exec DEALLOCATE returned no results"

497− Just deallocResult -> okResult_ deallocResult

460+ Just deallocResult -> do

461+ status <- LibPQ.resultStatus deallocResult

462+ unless (status == LibPQ.CommandOk) . error $

463+ "traversePrepared: DEALLOCATE status " <> show status

498 return (K ())

464 return (K ())

499

465

500 liftPQ pq = PQ $ \ (K conn) -> do

466 liftPQ pq = PQ $ \ (K conn) -> do

501− y <- liftIO $ pq conn

467+ y <- liftBase $ pq conn

502 return (K y)

468 return (K y)

503

469

504−instance MonadPQ schemas m => MonadPQ schemas (IdentityT m)

470+instance MonadPQ schema m => MonadPQ schema (IdentityT m)

505−instance MonadPQ schemas m => MonadPQ schemas (ReaderT r m)

471+instance MonadPQ schema m => MonadPQ schema (ReaderT r m)

506−instance MonadPQ schemas m => MonadPQ schemas (Strict.StateT s m)

472+instance MonadPQ schema m => MonadPQ schema (Strict.StateT s m)

507−instance MonadPQ schemas m => MonadPQ schemas (Lazy.StateT s m)

473+instance MonadPQ schema m => MonadPQ schema (Lazy.StateT s m)

508−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.WriterT w m)

474+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.WriterT w m)

509−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.WriterT w m)

475+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.WriterT w m)

510−instance MonadPQ schemas m => MonadPQ schemas (MaybeT m)

476+instance MonadPQ schema m => MonadPQ schema (MaybeT m)

511−instance MonadPQ schemas m => MonadPQ schemas (ExceptT e m)

477+instance MonadPQ schema m => MonadPQ schema (ExceptT e m)

512−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Strict.RWST r w s m)

478+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Strict.RWST r w s m)

513−instance (Monoid w, MonadPQ schemas m) => MonadPQ schemas (Lazy.RWST r w s m)

479+instance (Monoid w, MonadPQ schema m) => MonadPQ schema (Lazy.RWST r w s m)

514−instance MonadPQ schemas m => MonadPQ schemas (ContT r m)

480+instance MonadPQ schema m => MonadPQ schema (ContT r m)

515−

481+instance MonadPQ schema m => MonadPQ schema (ListT m)

482+

516−instance (Monad m, schemas0 ~ schemas1)

483+instance (Monad m, schema0 ~ schema1)

517− => Applicative (PQ schemas0 schemas1 m) where

484+ => Applicative (PQ schema0 schema1 m) where

518 pure x = PQ $ \ _conn -> pure (K x)

485 pure x = PQ $ \ _conn -> pure (K x)

519 (<*>) = pqAp

486 (<*>) = pqAp

520

487

521−instance (Monad m, schemas0 ~ schemas1)

488+instance (Monad m, schema0 ~ schema1)

522− => Monad (PQ schemas0 schemas1 m) where

489+ => Monad (PQ schema0 schema1 m) where

523 return = pure

490 return = pure

524 (>>=) = flip pqBind

491 (>>=) = flip pqBind

525

492

526−instance (Monad m, schemas0 ~ schemas1)

493+instance schema0 ~ schema1 => MFunctor (PQ schema0 schema1) where

527− => Fail.MonadFail (PQ schemas0 schemas1 m) where

528− fail = Fail.fail

529−

530−instance schemas0 ~ schemas1 => MFunctor (PQ schemas0 schemas1) where

531 hoist f (PQ pq) = PQ (f . pq)

494 hoist f (PQ pq) = PQ (f . pq)

532

495

533−instance schemas0 ~ schemas1 => MonadTrans (PQ schemas0 schemas1) where

496+instance schema0 ~ schema1 => MonadTrans (PQ schema0 schema1) where

534 lift m = PQ $ \ _conn -> do

497 lift m = PQ $ \ _conn -> do

535 x <- m

498 x <- m

536 return (K x)

499 return (K x)

537

500

538−instance schemas0 ~ schemas1 => MMonad (PQ schemas0 schemas1) where

501+instance schema0 ~ schema1 => MMonad (PQ schema0 schema1) where

539 embed f (PQ pq) = PQ $ \ conn -> do

502 embed f (PQ pq) = PQ $ \ conn -> do

540 evalPQ (f (pq conn)) conn

503 evalPQ (f (pq conn)) conn

541

504

542−instance (MonadIO m, schema0 ~ schema1)

505+instance (MonadBase b m, schema0 ~ schema1)

543− => MonadIO (PQ schema0 schema1 m) where

506+ => MonadBase b (PQ schema0 schema1 m) where

544− liftIO = lift . liftIO

507+ liftBase = lift . liftBase

545

508

546−instance (MonadUnliftIO m, schemas0 ~ schemas1)

509+-- | A snapshot of the state of a `PQ` computation.

547− => MonadUnliftIO (PQ schemas0 schemas1 m) where

510+type PQRun schema =

548− withRunInIO

511+ forall m x. Monad m => PQ schema schema m x -> m (K x schema)

549− :: ((forall a . PQ schemas0 schema1 m a -> IO a) -> IO b)

512+

550− -> PQ schemas0 schema1 m b

513+-- | Helper function in defining `MonadBaseControl` instance for `PQ`.

551− withRunInIO inner = PQ $ \conn ->

514+pqliftWith :: Functor m => (PQRun schema -> m a) -> PQ schema schema m a

552− withRunInIO $ \(run :: (forall x . m x -> IO x)) ->

515+pqliftWith f = PQ $ \ conn ->

553− K <$> inner (\pq -> run $ unK <$> unPQ pq conn)

516+ fmap K (f $ \ pq -> unPQ pq conn)

517+

518+instance (MonadBaseControl b m, schema0 ~ schema1)

519+ => MonadBaseControl b (PQ schema0 schema1 m) where

520+ type StM (PQ schema0 schema1 m) x = StM m (K x schema0)

521+ liftBaseWith f =

522+ pqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

523+ restoreM = PQ . const . restoreM

554

524

555-- | Get a row corresponding to a given row number from a `LibPQ.Result`,

525-- | Get a row corresponding to a given row number from a `LibPQ.Result`,

556-- throwing an exception if the row number is out of bounds.

526-- throwing an exception if the row number is out of bounds.

557getRow

527getRow

558− :: (FromRow columns y, MonadIO io)

528+ :: (FromRow columns y, MonadBase IO io)

559 => LibPQ.Row

529 => LibPQ.Row

560 -- ^ row number

530 -- ^ row number

561 -> K LibPQ.Result columns

531 -> K LibPQ.Result columns

562 -- ^ result

532 -- ^ result

563 -> io y

533 -> io y

564−getRow r (K result :: K LibPQ.Result columns) = liftIO $ do

534+getRow r (K result :: K LibPQ.Result columns) = liftBase $ do

565 numRows <- LibPQ.ntuples result

535 numRows <- LibPQ.ntuples result

566− when (numRows < r) $ throw $ ResultException $

536+ when (numRows < r) $ error $

567− "getRow: expected at least " <> pack (show r) <> "rows but only saw "

537+ "getRow: expected at least " <> show r <> "rows but only saw "

568− <> pack (show numRows)

538+ <> show numRows

569 let len = fromIntegral (lengthSList (Proxy @columns))

539 let len = fromIntegral (lengthSList (Proxy @columns))

570 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

540 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

571 case fromList row' of

541 case fromList row' of

572− Nothing -> throw $ ResultException "getRow: found unexpected length"

542+ Nothing -> error "getRow: found unexpected length"

573− Just row -> case fromRow @columns row of

543+ Just row -> return $ fromRow @columns row

574− Left parseError -> throw $ ParseException $ "getRow: " <> parseError

575− Right y -> return y

576

544

577-- | Intended to be used for unfolding in streaming libraries, `nextRow`

545-- | Intended to be used for unfolding in streaming libraries, `nextRow`

578-- takes a total number of rows (which can be found with `ntuples`)

546-- takes a total number of rows (which can be found with `ntuples`)

579-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,

547-- and a `LibPQ.Result` and given a row number if it's too large returns `Nothing`,

580-- otherwise returning the row along with the next row number.

548-- otherwise returning the row along with the next row number.

581nextRow

549nextRow

582− :: (FromRow columns y, MonadIO io)

550+ :: (FromRow columns y, MonadBase IO io)

583 => LibPQ.Row -- ^ total number of rows

551 => LibPQ.Row -- ^ total number of rows

584 -> K LibPQ.Result columns -- ^ result

552 -> K LibPQ.Result columns -- ^ result

585 -> LibPQ.Row -- ^ row number

553 -> LibPQ.Row -- ^ row number

586 -> io (Maybe (LibPQ.Row,y))

554 -> io (Maybe (LibPQ.Row,y))

587nextRow total (K result :: K LibPQ.Result columns) r

555nextRow total (K result :: K LibPQ.Result columns) r

588− = liftIO $ if r >= total then return Nothing else do

556+ = liftBase $ if r >= total then return Nothing else do

589 let len = fromIntegral (lengthSList (Proxy @columns))

557 let len = fromIntegral (lengthSList (Proxy @columns))

590 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

558 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

591 case fromList row' of

559 case fromList row' of

592− Nothing -> throw $ ResultException "nextRow: found unexpected length"

560+ Nothing -> error "nextRow: found unexpected length"

593− Just row -> case fromRow @columns row of

594− Left parseError -> throw $ ParseException $ "nextRow: " <> parseError

595− Right y -> return $ Just (r+1, y)

561+ Just row -> return $ Just (r+1, fromRow @columns row)

596

562

597-- | Get all rows from a `LibPQ.Result`.

563-- | Get all rows from a `LibPQ.Result`.

598getRows

564getRows

599− :: (FromRow columns y, MonadIO io)

565+ :: (FromRow columns y, MonadBase IO io)

600 => K LibPQ.Result columns -- ^ result

566 => K LibPQ.Result columns -- ^ result

601 -> io [y]

567 -> io [y]

602−getRows (K result :: K LibPQ.Result columns) = liftIO $ do

568+getRows (K result :: K LibPQ.Result columns) = liftBase $ do

603 let len = fromIntegral (lengthSList (Proxy @columns))

569 let len = fromIntegral (lengthSList (Proxy @columns))

604 numRows <- LibPQ.ntuples result

570 numRows <- LibPQ.ntuples result

605 for [0 .. numRows - 1] $ \ r -> do

571 for [0 .. numRows - 1] $ \ r -> do

606 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

572 row' <- traverse (LibPQ.getvalue result r) [0 .. len - 1]

607 case fromList row' of

573 case fromList row' of

608− Nothing -> throw $ ResultException "getRows: found unexpected length"

574+ Nothing -> error "getRows: found unexpected length"

609− Just row -> case fromRow @columns row of

575+ Just row -> return $ fromRow @columns row

610− Left parseError -> throw $ ParseException $ "getRows: " <> parseError

611− Right y -> return y

612

576

613-- | Get the first row if possible from a `LibPQ.Result`.

577-- | Get the first row if possible from a `LibPQ.Result`.

614firstRow

578firstRow

615− :: (FromRow columns y, MonadIO io)

579+ :: (FromRow columns y, MonadBase IO io)

616 => K LibPQ.Result columns -- ^ result

580 => K LibPQ.Result columns -- ^ result

617 -> io (Maybe y)

581 -> io (Maybe y)

618−firstRow (K result :: K LibPQ.Result columns) = liftIO $ do

582+firstRow (K result :: K LibPQ.Result columns) = liftBase $ do

619 numRows <- LibPQ.ntuples result

583 numRows <- LibPQ.ntuples result

620 if numRows <= 0 then return Nothing else do

584 if numRows <= 0 then return Nothing else do

621 let len = fromIntegral (lengthSList (Proxy @columns))

585 let len = fromIntegral (lengthSList (Proxy @columns))

622 row' <- traverse (LibPQ.getvalue result 0) [0 .. len - 1]

586 row' <- traverse (LibPQ.getvalue result 0) [0 .. len - 1]

623 case fromList row' of

587 case fromList row' of

624− Nothing -> throw $ ResultException "firstRow: found unexpected length"

588+ Nothing -> error "firstRow: found unexpected length"

625− Just row -> case fromRow @columns row of

589+ Just row -> return . Just $ fromRow @columns row

626− Left parseError -> throw $ ParseException $ "firstRow: " <> parseError

627− Right y -> return $ Just y

628

590

629-- | Lifts actions on results from @LibPQ@.

591-- | Lifts actions on results from @LibPQ@.

630liftResult

592liftResult

631− :: MonadIO io

593+ :: MonadBase IO io

632 => (LibPQ.Result -> IO x)

594 => (LibPQ.Result -> IO x)

633 -> K LibPQ.Result results -> io x

595 -> K LibPQ.Result results -> io x

634−liftResult f (K result) = liftIO $ f result

596+liftResult f (K result) = liftBase $ f result

635

597

636-- | Returns the number of rows (tuples) in the query result.

598-- | Returns the number of rows (tuples) in the query result.

637−ntuples :: MonadIO io => K LibPQ.Result columns -> io LibPQ.Row

599+ntuples :: MonadBase IO io => K LibPQ.Result columns -> io LibPQ.Row

638ntuples = liftResult LibPQ.ntuples

600ntuples = liftResult LibPQ.ntuples

639

601

640-- | Returns the result status of the command.

602-- | Returns the result status of the command.

641−resultStatus :: MonadIO io => K LibPQ.Result results -> io LibPQ.ExecStatus

603+resultStatus :: MonadBase IO io => K LibPQ.Result results -> io LibPQ.ExecStatus

642resultStatus = liftResult LibPQ.resultStatus

604resultStatus = liftResult LibPQ.resultStatus

643

605

644-- | Returns the error message most recently generated by an operation

606-- | Returns the error message most recently generated by an operation

645-- on the connection.

607-- on the connection.

646resultErrorMessage

608resultErrorMessage

647− :: MonadIO io => K LibPQ.Result results -> io (Maybe ByteString)

609+ :: MonadBase IO io => K LibPQ.Result results -> io (Maybe ByteString)

648resultErrorMessage = liftResult LibPQ.resultErrorMessage

610resultErrorMessage = liftResult LibPQ.resultErrorMessage

649−

650−-- | Returns the error code most recently generated by an operation

651−-- on the connection.

652−--

653−-- https://www.postgresql.org/docs/current/static/errcodes-appendix.html

654−resultErrorCode

655− :: MonadIO io

656− => K LibPQ.Result results

657− -> io (Maybe ByteString)

658−resultErrorCode = liftResult (flip LibPQ.resultErrorField LibPQ.DiagSqlstate)

659−

660−-- | the state of LibPQ

661−data PQState = PQState

662− { sqlExecStatus :: LibPQ.ExecStatus

663− , sqlStateCode :: Maybe ByteString

664− -- ^ https://www.postgresql.org/docs/current/static/errcodes-appendix.html

665− , sqlErrorMessage :: Maybe ByteString

666− } deriving (Eq, Show)

667−

668−-- | `Exception`s that can be thrown by Squeal.

669−data SquealException

670− = PQException PQState

671− | ResultException Text

672− | ParseException Text

673− deriving (Eq, Show)

674−instance Exception SquealException

675−

676−okResult_ :: MonadIO io => LibPQ.Result -> io ()

677−okResult_ result = liftIO $ do

678− status <- LibPQ.resultStatus result

679− case status of

680− LibPQ.CommandOk -> return ()

681− LibPQ.TuplesOk -> return ()

682− _ -> do

683− stateCode <- LibPQ.resultErrorField result LibPQ.DiagSqlstate

684− msg <- LibPQ.resultErrorMessage result

685− throw . PQException $ PQState status stateCode msg

686−

687−-- | Check if a `LibPQ.Result`'s status is either `LibPQ.CommandOk`

688−-- or `LibPQ.TuplesOk` otherwise `throw` a `PQException`.

689−okResult :: MonadIO io => K LibPQ.Result row -> io ()

690−okResult = okResult_ . unK

691−

692−-- | Catch `SquealException`s.

693−catchSqueal

694− :: MonadUnliftIO io

695− => io a

696− -> (SquealException -> io a) -- ^ handler

697− -> io a

698−catchSqueal = catch

699−

700−-- | Handle `SquealException`s.

701−handleSqueal

702− :: MonadUnliftIO io

703− => (SquealException -> io a) -- ^ handler

704− -> io a -> io a

705−handleSqueal = handle

706−

707−-- | `Either` return a `SquealException` or a result.

708−trySqueal

709− :: MonadUnliftIO io

710− => io a

711− -> io (Either SquealException a)

712−trySqueal = try

squeal-postgresql/src/Squeal/PostgreSQL/Pool.hs+79−69

@@ -1,40 +1,17 @@

1{-|

2−Module: Squeal.PostgreSQL.Pool

2+Module: Squeal.PostgreSQL.Definition

3−Description: Connection pools

3+Description: Pooled connections

4Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

8−Connection pools.

8+A `MonadPQ` for pooled connections.

9−

10−Typical use case would be to create your pool using `createConnectionPool`

11−and run anything that requires the pool connection with `usingConnectionPool`.

12−

13−Here's a simplified example:

14−

15−>>> import Squeal.PostgreSQL

16−

17−>>> :{

18−do

19− let

20− query :: Query_ (Public '[]) () (Only Char)

21− query = values_ (literal 'a' `as` #fromOnly)

22− pool <- createConnectionPool "host=localhost port=5432 dbname=exampledb" 1 0.5 10

23− chr <- usingConnectionPool pool $ do

24− result <- runQuery query

25− Just (Only a) <- firstRow result

26− return a

27− destroyConnectionPool pool

28− putChar chr

29−:}

30−a

31-}

9-}

33{-# LANGUAGE

11{-# LANGUAGE

34 DeriveFunctor

12 DeriveFunctor

35 , FlexibleContexts

13 , FlexibleContexts

36 , FlexibleInstances

14 , FlexibleInstances

37− , InstanceSigs

38 , MultiParamTypeClasses

15 , MultiParamTypeClasses

39 , RankNTypes

16 , RankNTypes

40 , ScopedTypeVariables

17 , ScopedTypeVariables

@@ -45,24 +22,34 @@ a

46module Squeal.PostgreSQL.Pool

23module Squeal.PostgreSQL.Pool

47 ( -- * Pools

24 ( -- * Pools

48− Pool

25+ PoolPQ (..)

49 , createConnectionPool

26 , createConnectionPool

50− , usingConnectionPool

27+ , Pool

51− , destroyConnectionPool

28+ , destroyAllResources

29+ , PoolPQRun

30+ , poolpqliftWith

52 ) where

31 ) where

33+import Control.Monad.Base

34+import Control.Monad.Trans

35+import Control.Monad.Trans.Control

54import Data.ByteString

36import Data.ByteString

37+import Data.Pool

55import Data.Time

38import Data.Time

56−import Generics.SOP (K(..), unK)

39+import Generics.SOP (K(..))

57−import UnliftIO (MonadUnliftIO (..))

58−import UnliftIO.Pool (Pool, createPool, destroyAllResources, withResource)

60import Squeal.PostgreSQL.PQ

41import Squeal.PostgreSQL.PQ

42+import Squeal.PostgreSQL.Schema

43+

44+-- | `PoolPQ` @schema@ should be a drop-in replacement for `PQ` @schema schema@.

45+newtype PoolPQ (schema :: SchemaType) m x =

46+ PoolPQ { runPoolPQ :: Pool (K Connection schema) -> m x }

47+ deriving Functor

62-- | Create a striped pool of connections.

49-- | Create a striped pool of connections.

63-- Although the garbage collector will destroy all idle connections when the pool is garbage collected it's recommended to manually `destroyAllResources` when you're done with the pool so that the connections are freed up as soon as possible.

50-- Although the garbage collector will destroy all idle connections when the pool is garbage collected it's recommended to manually `destroyAllResources` when you're done with the pool so that the connections are freed up as soon as possible.

64createConnectionPool

51createConnectionPool

65− :: MonadUnliftIO io

52+ :: MonadBase IO io

66 => ByteString

53 => ByteString

67 -- ^ The passed string can be empty to use all default parameters, or it can

54 -- ^ The passed string can be empty to use all default parameters, or it can

68 -- contain one or more parameter settings separated by whitespace.

55 -- contain one or more parameter settings separated by whitespace.

@@ -78,45 +65,68 @@ createConnectionPool

78 -> Int

65 -> Int

79 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.

66 -- ^ Maximum number of connections to keep open per stripe. The smallest acceptable value is 1.

80 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.

67 -- Requests for connections will block if this limit is reached on a single stripe, even if other stripes have idle connections available.

81− -> io (Pool (K Connection schemas))

68+ -> io (Pool (K Connection schema))

82−createConnectionPool conninfo stripes idle maxResrc =

69+createConnectionPool conninfo stripes idle maxResrc = liftBase $

83 createPool (connectdb conninfo) finish stripes idle maxResrc

70 createPool (connectdb conninfo) finish stripes idle maxResrc

85−{-|

72+-- | `Applicative` instance for `PoolPQ`.

86−Temporarily take a connection from a `Pool`, perform an action with it,

73+instance Monad m => Applicative (PoolPQ schema m) where

87−and return it to the pool afterwards.

74+ pure x = PoolPQ $ \ _ -> pure x

75+ PoolPQ f <*> PoolPQ x = PoolPQ $ \ pool -> do

76+ f' <- f pool

77+ x' <- x pool

78+ return $ f' x'

89−If the pool has an idle connection available, it is used immediately.

80+-- | `Monad` instance for `PoolPQ`.

90−Otherwise, if the maximum number of connections has not yet been reached,

81+instance Monad m => Monad (PoolPQ schema m) where

91−a new connection is created and used.

82+ return = pure

92−If the maximum number of connections has been reached, this function blocks

83+ PoolPQ x >>= f = PoolPQ $ \ pool -> do

93−until a connection becomes available.

84+ x' <- x pool

94−-}

85+ runPoolPQ (f x') pool

95−usingConnectionPool

96− :: MonadUnliftIO io

97− => Pool (K Connection schemas) -- ^ pool

98− -> PQ schemas schemas io x -- ^ session

99− -> io x

100−usingConnectionPool pool (PQ session) = unK <$> withResource pool session

101

102−{- |

87+-- | `MonadTrans` instance for `PoolPQ`.

103−Destroy all connections in all stripes in the pool.

88+instance MonadTrans (PoolPQ schema) where

104−Note that this will ignore any exceptions in the destroy function.

89+ lift m = PoolPQ $ \ _pool -> m

105

106−This function is useful when you detect that all connections

91+-- | `MonadBase` instance for `PoolPQ`.

107−in the pool are broken. For example after a database has been

92+instance MonadBase b m => MonadBase b (PoolPQ schema m) where

108−restarted all connections opened before the restart will be broken.

93+ liftBase = lift . liftBase

109−In that case it's better to close those connections so that

110−`usingConnectionPool` won't take a broken connection from the pool

111−but will open a new connection instead.

112

113−Another use-case for this function is that when you know you are done

95+-- | `MonadPQ` instance for `PoolPQ`.

114−with the pool you can destroy all idle connections immediately

96+instance MonadBaseControl IO io => MonadPQ schema (PoolPQ schema io) where

115−instead of waiting on the garbage collector to destroy them,

97+ manipulateParams manipulation params = PoolPQ $ \ pool -> do

116−thus freeing up those connections sooner.

98+ withResource pool $ \ conn -> do

117−-}

99+ (K result :: K (K Result ys) schema) <- flip unPQ conn $

118−destroyConnectionPool

100+ manipulateParams manipulation params

119− :: MonadUnliftIO io

101+ return result

120− => Pool (K Connection schemas) -- ^ pool

102+ traversePrepared manipulation params = PoolPQ $ \ pool ->

121− -> io ()

103+ withResource pool $ \ conn -> do

122−destroyConnectionPool = destroyAllResources

104+ (K result :: K (list (K Result ys)) schema) <- flip unPQ conn $

105+ traversePrepared manipulation params

106+ return result

107+ traversePrepared_ manipulation params = PoolPQ $ \ pool -> do

108+ withResource pool $ \ conn -> do

109+ (_ :: K () schema) <- flip unPQ conn $

110+ traversePrepared_ manipulation params

111+ return ()

112+ liftPQ m = PoolPQ $ \ pool ->

113+ withResource pool $ \ conn -> do

114+ (K result :: K result schema) <- flip unPQ conn $

115+ liftPQ m

116+ return result

117+

118+-- | A snapshot of the state of a `PoolPQ` computation.

119+type PoolPQRun schema =

120+ forall m x. Monad m => PoolPQ schema m x -> m x

121+

122+-- | Helper function in defining `MonadBaseControl` instance for `PoolPQ`.

123+poolpqliftWith :: Functor m => (PoolPQRun schema -> m a) -> PoolPQ schema m a

124+poolpqliftWith f = PoolPQ $ \ pool ->

125+ (f $ \ pq -> runPoolPQ pq pool)

126+

127+-- | `MonadBaseControl` instance for `PoolPQ`.

128+instance MonadBaseControl b m => MonadBaseControl b (PoolPQ schema m) where

129+ type StM (PoolPQ schema m) x = StM m x

130+ liftBaseWith f =

131+ poolpqliftWith $ \ run -> liftBaseWith $ \ runInBase -> f $ runInBase . run

132+ restoreM = PoolPQ . const . restoreM

squeal-postgresql/src/Squeal/PostgreSQL/Query.hs+451−717

@@ -1,7 +1,7 @@

1{-|

2Module: Squeal.PostgreSQL.Query

3Description: Squeal queries

4−Copyright: (c) Eitan Chatav, 2019

4+Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

@@ -9,81 +9,68 @@ Squeal queries.

9-}

11{-# LANGUAGE

12− ConstraintKinds

13− , DeriveGeneric

12+ DeriveGeneric

14− , FlexibleContexts

15− , FlexibleInstances

16 , GADTs

13 , GADTs

17 , GeneralizedNewtypeDeriving

14 , GeneralizedNewtypeDeriving

18 , LambdaCase

15 , LambdaCase

19− , MultiParamTypeClasses

20− , OverloadedLabels

21 , OverloadedStrings

16 , OverloadedStrings

22− , QuantifiedConstraints

23− , ScopedTypeVariables

24 , StandaloneDeriving

17 , StandaloneDeriving

25− , TypeApplications

26− , TypeFamilies

27 , TypeInType

18 , TypeInType

28 , TypeOperators

19 , TypeOperators

29− , RankNTypes

30− , UndecidableInstances

31− #-}

20+#-}

33module Squeal.PostgreSQL.Query

22module Squeal.PostgreSQL.Query

34 ( -- * Queries

23 ( -- * Queries

35− Query_

24+ Query (UnsafeQuery, renderQuery)

36− , Query (..)

37− -- ** Select

38− , select

39− , select_

40− , selectDistinct

41− , selectDistinct_

42− , selectDistinctOn

43− , selectDistinctOn_

44− , Selection (..)

45− -- ** Values

46− , values

47− , values_

48− -- ** Set Operations

49 , union

25 , union

50 , unionAll

26 , unionAll

51 , intersect

27 , intersect

52 , intersectAll

28 , intersectAll

53 , except

29 , except

54 , exceptAll

30 , exceptAll

55− -- ** With

31+ -- * Select

56− , With (..)

32+ , select

57− , CommonTableExpression (..)

33+ , selectDistinct

58− , withRecursive

34+ , selectStar

35+ , selectDistinctStar

36+ , selectDotStar

37+ , selectDistinctDotStar

38+ , values

59 -- * Table Expressions

39 -- * Table Expressions

60 , TableExpression (..)

40 , TableExpression (..)

41+ , renderTableExpression

61 , from

42 , from

62 , where_

43 , where_

63− , groupBy

44+ , group

64 , having

45 , having

46+ , orderBy

65 , limit

47 , limit

66 , offset

48 , offset

67− -- * From Clauses

49+ -- * From

68 , FromClause (..)

50 , FromClause (..)

69 , table

51 , table

70 , subquery

52 , subquery

71 , view

53 , view

72− , common

73 , crossJoin

54 , crossJoin

74 , innerJoin

55 , innerJoin

75 , leftOuterJoin

56 , leftOuterJoin

76 , rightOuterJoin

57 , rightOuterJoin

77 , fullOuterJoin

58 , fullOuterJoin

78 -- * Grouping

59 -- * Grouping

79− , By (..)

60+ , By (By, By2)

61+ , renderBy

80− , GroupByClause (..)

62+ , GroupByClause (NoGroups, Group)

63+ , renderGroupByClause

81− , HavingClause (..)

64+ , HavingClause (NoHaving, Having)

65+ , renderHavingClause

66+ -- * Sorting

67+ , SortExpression (..)

68+ , renderSortExpression

82 ) where

69 ) where

84import Control.DeepSeq

71import Control.DeepSeq

85import Data.ByteString (ByteString)

72import Data.ByteString (ByteString)

86−import Data.Kind (Type)

73+import Data.Monoid hiding (All)

87import Data.String

74import Data.String

88import Data.Word

75import Data.Word

89import Generics.SOP hiding (from)

76import Generics.SOP hiding (from)

@@ -91,555 +78,358 @@ import GHC.TypeLits

92import qualified GHC.Generics as GHC

79import qualified GHC.Generics as GHC

94−import Squeal.PostgreSQL.Alias

95import Squeal.PostgreSQL.Expression

81import Squeal.PostgreSQL.Expression

96−import Squeal.PostgreSQL.Expression.Logic

97−import Squeal.PostgreSQL.Expression.Sort

98−import Squeal.PostgreSQL.Expression.Window

99−import Squeal.PostgreSQL.List

100−import Squeal.PostgreSQL.PG

101import Squeal.PostgreSQL.Render

82import Squeal.PostgreSQL.Render

102import Squeal.PostgreSQL.Schema

83import Squeal.PostgreSQL.Schema

103

104−-- $setup

105−-- >>> import Squeal.PostgreSQL

106−-- >>> import Data.Int (Int32, Int64)

107−-- >>> import Data.Monoid (Sum (..))

108−-- >>> import Data.Text (Text)

109−-- >>> import qualified Generics.SOP as SOP

110−

111−{- |

112−The process of retrieving or the command to retrieve data from

113−a database is called a `Query`.

114−

115−The general `Query` type is parameterized by

116−

117−* @outer :: FromType@ - outer scope for a correlated subquery,

118−* @commons :: FromType@ - scope for all `common` table expressions,

119−* @schemas :: SchemasType@ - scope for all `table`s and `view`s,

120−* @params :: [NullityType]@ - scope for all `Squeal.Expression.Parameter.parameter`s,

121−* @row :: RowType@ - return type of the `Query`.

122−-}

123−newtype Query

124− (outer :: FromType)

125− (commons :: FromType)

126− (schemas :: SchemasType)

127− (params :: [NullityType])

128− (row :: RowType)

129− = UnsafeQuery { renderQuery :: ByteString }

130− deriving (GHC.Generic,Show,Eq,Ord,NFData)

131−instance RenderSQL (Query outer commons schemas params row) where renderSQL = renderQuery

132−

133{- |

85{- |

134−The top level `Query_` type is parameterized by a @schemas@ `SchemasType`,

86+The process of retrieving or the command to retrieve data from a database

135−against which the query is type-checked, an input @parameters@ Haskell `Type`,

87+is called a `Query`. The `select`, `selectStar`, `selectDotStar`,

136−and an ouput row Haskell `Type`.

88+`selectDistinct`, `selectDistinctStar` and `selectDistinctDotStar` commands

137−

89+are used to specify queries.

138−A top-level query can be run

139−using `Squeal.PostgreSQL.PQ.runQueryParams`, or if @parameters = ()@

140−using `Squeal.PostgreSQL.PQ.runQuery`.

141−

142−Generally, @parameters@ will be a Haskell tuple or record whose entries

143−may be referenced using positional

144−`Squeal.PostgreSQL.Expression.Parameter.parameter`s and @row@ will be a

145−Haskell record, whose entries will be targeted using overloaded labels.

146−

147−Let's see some examples of queries.

148−

149−>>> :set -XDeriveAnyClass -XDerivingStrategies

150−>>> :{

151−data Row a b = Row { col1 :: a, col2 :: b }

152− deriving stock (GHC.Generic)

153− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

154−:}

155

156simple query:

91simple query:

157

158−>>> type Columns = '["col1" ::: 'NoDef :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]

159−>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]

160>>> :{

93>>> :{

161let

94let

162− query :: Query_ (Public Schema) () (Row Int32 Int32)

95+ query :: Query

96+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

97+ '[]

98+ '["col" ::: 'Null 'PGint4]

163− query = select Star (from (table #tab))

99+ query = selectStar (from (table (#tab `As` #t)))

164−in printSQL query

100+in renderQuery query

165:}

101:}

166−SELECT * FROM "tab" AS "tab"

102+"SELECT * FROM \"tab\" AS \"t\""

167

103

168restricted query:

104restricted query:

169

105

170>>> :{

106>>> :{

171let

107let

172− query :: Query_ (Public Schema) () (Row Int32 Int32)

108+ query :: Query

109+ '[ "tab" ::: 'Table ('[] :=>

110+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

111+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

112+ '[]

113+ '[ "sum" ::: 'NotNull 'PGint4

114+ , "col1" ::: 'NotNull 'PGint4 ]

173− query =

115+ query =

116+ select

174− select_ ((#col1 + #col2) `as` #col1 :* #col1 `as` #col2)

117+ ((#col1 + #col2) `As` #sum :* #col1 `As` #col1 :* Nil)

175− ( from (table #tab)

118+ ( from (table (#tab `As` #t))

176 & where_ (#col1 .> #col2)

119 & where_ (#col1 .> #col2)

177 & where_ (#col2 .> 0) )

120 & where_ (#col2 .> 0) )

178−in printSQL query

121+in renderQuery query

179:}

122:}

180−SELECT ("col1" + "col2") AS "col1", "col1" AS "col2" FROM "tab" AS "tab" WHERE (("col1" > "col2") AND ("col2" > 0))

123+"SELECT (\"col1\" + \"col2\") AS \"sum\", \"col1\" AS \"col1\" FROM \"tab\" AS \"t\" WHERE ((\"col1\" > \"col2\") AND (\"col2\" > 0))"

181

124

182subquery:

125subquery:

183

126

184>>> :{

127>>> :{

185let

128let

186− query :: Query_ (Public Schema) () (Row Int32 Int32)

129+ query :: Query

130+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

131+ '[]

132+ '["col" ::: 'Null 'PGint4]

133+ query =

134+ selectStar

187− query = select Star (from (subquery (select Star (from (table #tab)) `as` #sub)))

135+ (from (subquery (selectStar (from (table (#tab `As` #t))) `As` #sub)))

188−in printSQL query

136+in renderQuery query

189:}

137:}

190−SELECT * FROM (SELECT * FROM "tab" AS "tab") AS "sub"

138+"SELECT * FROM (SELECT * FROM \"tab\" AS \"t\") AS \"sub\""

191

139

192limits and offsets:

140limits and offsets:

193

141

194>>> :{

142>>> :{

195let

143let

196− query :: Query_ (Public Schema) () (Row Int32 Int32)

144+ query :: Query

145+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

146+ '[]

147+ '["col" ::: 'Null 'PGint4]

148+ query = selectStar

197− query = select Star (from (table #tab) & limit 100 & offset 2 & limit 50 & offset 2)

149+ (from (table (#tab `As` #t)) & limit 100 & offset 2 & limit 50 & offset 2)

198−in printSQL query

150+in renderQuery query

199:}

151:}

200−SELECT * FROM "tab" AS "tab" LIMIT 50 OFFSET 4

152+"SELECT * FROM \"tab\" AS \"t\" LIMIT 50 OFFSET 4"

201

153

202parameterized query:

154parameterized query:

203

155

204>>> :{

156>>> :{

205let

157let

206− query :: Query_ (Public Schema) (Only Int32) (Row Int32 Int32)

158+ query :: Query

159+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGfloat8])]

160+ '[ 'NotNull 'PGfloat8]

161+ '["col" ::: 'NotNull 'PGfloat8]

162+ query = selectStar

207− query = select Star (from (table #tab) & where_ (#col1 .> param @1))

163+ (from (table (#tab `As` #t)) & where_ (#col .> param @1))

208−in printSQL query

164+in renderQuery query

209:}

165:}

210−SELECT * FROM "tab" AS "tab" WHERE ("col1" > ($1 :: int4))

166+"SELECT * FROM \"tab\" AS \"t\" WHERE (\"col\" > ($1 :: float8))"

211

167

212aggregation query:

168aggregation query:

213

169

214>>> :{

170>>> :{

215let

171let

216− query :: Query_ (Public Schema) () (Row Int64 Int32)

172+ query :: Query

173+ '[ "tab" ::: 'Table ('[] :=>

174+ '[ "col1" ::: 'NoDef :=> 'NotNull 'PGint4

175+ , "col2" ::: 'NoDef :=> 'NotNull 'PGint4 ])]

176+ '[]

177+ '[ "sum" ::: 'NotNull 'PGint4

178+ , "col1" ::: 'NotNull 'PGint4 ]

217 query =

179 query =

218− select_ ((fromNull 0 (sum_ (All #col2))) `as` #col1 :* #col1 `as` #col2)

180+ select (sum_ #col2 `As` #sum :* #col1 `As` #col1 :* Nil)

219− ( from (table (#tab `as` #table1))

181+ ( from (table (#tab `As` #table1))

220− & groupBy #col1

182+ & group (By #col1 :* Nil)

221− & having (sum_ (Distinct #col2) .> 1) )

183+ & having (#col1 + sum_ #col2 .> 1) )

222−in printSQL query

184+in renderQuery query

223:}

185:}

224−SELECT COALESCE(sum(ALL "col2"), 0) AS "col1", "col1" AS "col2" FROM "tab" AS "table1" GROUP BY "col1" HAVING (sum(DISTINCT "col2") > 1)

186+"SELECT sum(\"col2\") AS \"sum\", \"col1\" AS \"col1\" FROM \"tab\" AS \"table1\" GROUP BY \"col1\" HAVING ((\"col1\" + sum(\"col2\")) > 1)"

225

187

226sorted query:

188sorted query:

227

189

228>>> :{

190>>> :{

229let

191let

230− query :: Query_ (Public Schema) () (Row Int32 Int32)

192+ query :: Query

193+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

194+ '[]

195+ '["col" ::: 'Null 'PGint4]

196+ query = selectStar

231− query = select Star (from (table #tab) & orderBy [#col1 & Asc])

197+ (from (table (#tab `As` #t)) & orderBy [#col & AscNullsFirst])

232−in printSQL query

198+in renderQuery query

233:}

199:}

234−SELECT * FROM "tab" AS "tab" ORDER BY "col1" ASC

200+"SELECT * FROM \"tab\" AS \"t\" ORDER BY \"col\" ASC NULLS FIRST"

235

201

236joins:

202joins:

237

203

238−>>> :{

204+>>> :set -XFlexibleContexts

239−type OrdersColumns =

240− '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

241− , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

242− , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

243− , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4 ]

244−:}

245−

246−>>> :{

247−type OrdersConstraints =

248− '["pk_orders" ::: PrimaryKey '["id"]

249− ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]

250− ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"] ]

251−:}

252−

253−>>> type NamesColumns = '["id" ::: 'NoDef :=> 'NotNull 'PGint4, "name" ::: 'NoDef :=> 'NotNull 'PGtext]

254−>>> type CustomersConstraints = '["pk_customers" ::: PrimaryKey '["id"]]

255−>>> type ShippersConstraints = '["pk_shippers" ::: PrimaryKey '["id"]]

256−>>> :{

257−type OrdersSchema =

258− '[ "orders" ::: 'Table (OrdersConstraints :=> OrdersColumns)

259− , "customers" ::: 'Table (CustomersConstraints :=> NamesColumns)

260− , "shippers" ::: 'Table (ShippersConstraints :=> NamesColumns) ]

261−:}

262−

263−>>> :{

264−data Order = Order

265− { price :: Float

266− , customerName :: Text

267− , shipperName :: Text

268− } deriving GHC.Generic

269−instance SOP.Generic Order

270−instance SOP.HasDatatypeInfo Order

271−:}

272−

273>>> :{

205>>> :{

274let

206let

275− query :: Query_ (Public OrdersSchema) () Order

207+ query :: Query

208+ '[ "orders" ::: 'Table (

209+ '["pk_orders" ::: PrimaryKey '["id"]

210+ ,"fk_customers" ::: ForeignKey '["customer_id"] "customers" '["id"]

211+ ,"fk_shippers" ::: ForeignKey '["shipper_id"] "shippers" '["id"]] :=>

212+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

213+ , "price" ::: 'NoDef :=> 'NotNull 'PGfloat4

214+ , "customer_id" ::: 'NoDef :=> 'NotNull 'PGint4

215+ , "shipper_id" ::: 'NoDef :=> 'NotNull 'PGint4

216+ ])

217+ , "customers" ::: 'Table (

218+ '["pk_customers" ::: PrimaryKey '["id"]] :=>

219+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

220+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

221+ ])

222+ , "shippers" ::: 'Table (

223+ '["pk_shippers" ::: PrimaryKey '["id"]] :=>

224+ '[ "id" ::: 'NoDef :=> 'NotNull 'PGint4

225+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext

226+ ])

227+ ]

228+ '[]

229+ '[ "order_price" ::: 'NotNull 'PGfloat4

230+ , "customer_name" ::: 'NotNull 'PGtext

231+ , "shipper_name" ::: 'NotNull 'PGtext

232+ ]

276− query = select_

233+ query = select

277− ( #o ! #price `as` #price :*

234+ ( #o ! #price `As` #order_price :*

278− #c ! #name `as` #customerName :*

235+ #c ! #name `As` #customer_name :*

279− #s ! #name `as` #shipperName )

236+ #s ! #name `As` #shipper_name :* Nil )

280− ( from (table (#orders `as` #o)

237+ ( from (table (#orders `As` #o)

281− & innerJoin (table (#customers `as` #c))

238+ & innerJoin (table (#customers `As` #c))

282 (#o ! #customer_id .== #c ! #id)

239 (#o ! #customer_id .== #c ! #id)

283− & innerJoin (table (#shippers `as` #s))

240+ & innerJoin (table (#shippers `As` #s))

284 (#o ! #shipper_id .== #s ! #id)) )

241 (#o ! #shipper_id .== #s ! #id)) )

285−in printSQL query

242+in renderQuery query

286:}

243:}

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")

244+"SELECT \"o\".\"price\" AS \"order_price\", \"c\".\"name\" AS \"customer_name\", \"s\".\"name\" AS \"shipper_name\" FROM \"orders\" AS \"o\" INNER JOIN \"customers\" AS \"c\" ON (\"o\".\"customer_id\" = \"c\".\"id\") INNER JOIN \"shippers\" AS \"s\" ON (\"o\".\"shipper_id\" = \"s\".\"id\")"

288

245

289self-join:

246self-join:

290

247

291>>> :{

248>>> :{

292let

249let

293− query :: Query_ (Public Schema) () (Row Int32 Int32)

250+ query :: Query

294− query = select

251+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

295− (#t1 & DotStar)

252+ '[]

253+ '["col" ::: 'Null 'PGint4]

254+ query = selectDotStar #t1

296− (from (table (#tab `as` #t1) & crossJoin (table (#tab `as` #t2))))

255+ (from (table (#tab `As` #t1) & crossJoin (table (#tab `As` #t2))))

297−in printSQL query

256+in renderQuery query

298−:}

299−SELECT "t1".* FROM "tab" AS "t1" CROSS JOIN "tab" AS "t2"

300−

301−value queries:

302−

303−>>> :{

304−let

305− query :: Query_ schemas () (Row String Bool)

306− query = values

307− ("true" `as` #col1 :* true `as` #col2)

308− ["false" `as` #col1 :* false `as` #col2]

309−in printSQL query

310:}

257:}

311−SELECT * FROM (VALUES (E'true', TRUE), (E'false', FALSE)) AS t ("col1", "col2")

258+"SELECT \"t1\".* FROM \"tab\" AS \"t1\" CROSS JOIN \"tab\" AS \"t2\""

312

259

313set operations:

260set operations:

314

261

315>>> :{

262>>> :{

316let

263let

317− query :: Query_ (Public Schema) () (Row Int32 Int32)

264+ query :: Query

318− query = select Star (from (table #tab)) `unionAll` select Star (from (table #tab))

265+ '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]

319−in printSQL query

266+ '[]

320−:}

267+ '["col" ::: 'Null 'PGint4]

321−(SELECT * FROM "tab" AS "tab") UNION ALL (SELECT * FROM "tab" AS "tab")

322−

323−with queries:

324−

325−>>> :{

326−let

327− query :: Query_ (Public Schema) () (Row Int32 Int32)

328− query = with (

329− select Star (from (table #tab)) `as` #cte1 :>>

330− select Star (from (common #cte1)) `as` #cte2

331− ) (select Star (from (common #cte2)))

332−in printSQL query

333−:}

334−WITH "cte1" AS (SELECT * FROM "tab" AS "tab"), "cte2" AS (SELECT * FROM "cte1" AS "cte1") SELECT * FROM "cte2" AS "cte2"

335−

336−window function queries

337−

338−>>> :{

339−let

340− query :: Query_ (Public Schema) () (Row Int32 Int64)

341− query = select

342− (#col1 & Also (rank `as` #col2 `Over` (partitionBy #col1 & orderBy [#col2 & Asc])))

343− (from (table #tab))

344−in printSQL query

345−:}

346−SELECT "col1" AS "col1", rank() OVER (PARTITION BY "col1" ORDER BY "col2" ASC) AS "col2" FROM "tab" AS "tab"

347−

348−correlated subqueries

349−

350−>>> :{

351−let

352− query :: Query_ (Public Schema) () (Only Int32)

353 query =

268 query =

354− select (#col1 `as` #fromOnly) (from (table (#tab `as` #t1))

269+ selectStar (from (table (#tab `As` #t)))

355− & where_ (exists (

270+ `unionAll`

356− select Star (from (table (#tab `as` #t2))

271+ selectStar (from (table (#tab `As` #t)))

357− & where_ (#t2 ! #col2 .== #t1 ! #col1)))))

358−in printSQL query

272+in renderQuery query

359:}

273:}

360−SELECT "col1" AS "fromOnly" FROM "tab" AS "t1" WHERE EXISTS (SELECT * FROM "tab" AS "t2" WHERE ("t2"."col2" = "t1"."col1"))

274+"(SELECT * FROM \"tab\" AS \"t\") UNION ALL (SELECT * FROM \"tab\" AS \"t\")"

361−

362-}

275-}

363−type family Query_

276+newtype Query

364− (schemas :: SchemasType)

277+ (schema :: SchemaType)

365− (parameters :: Type)

278+ (params :: [NullityType])

366− (row :: Type) where

279+ (columns :: RelationType)

367− Query_ schemas params row =

280+ = UnsafeQuery { renderQuery :: ByteString }

368− Query '[] '[] schemas (TuplePG params) (RowPG row)

281+ deriving (GHC.Generic,Show,Eq,Ord,NFData)

369

282

370-- | The results of two queries can be combined using the set operation

283-- | The results of two queries can be combined using the set operation

371−-- `union`. Duplicate rows are eliminated.

284+-- `union`. Duplicate rows are eliminated.

372union

285union

373− :: Query outer commons schemas params columns

286+ :: Query schema params columns

374− -> Query outer commons schemas params columns

287+ -> Query schema params columns

375− -> Query outer commons schemas params columns

288+ -> Query schema params columns

376q1 `union` q2 = UnsafeQuery $

289q1 `union` q2 = UnsafeQuery $

377− parenthesized (renderSQL q1)

290+ parenthesized (renderQuery q1)

378 <+> "UNION"

291 <+> "UNION"

379− <+> parenthesized (renderSQL q2)

292+ <+> parenthesized (renderQuery q2)

380

293

381-- | The results of two queries can be combined using the set operation

294-- | The results of two queries can be combined using the set operation

382-- `unionAll`, the disjoint union. Duplicate rows are retained.

295-- `unionAll`, the disjoint union. Duplicate rows are retained.

383unionAll

296unionAll

384− :: Query outer commons schemas params columns

297+ :: Query schema params columns

385− -> Query outer commons schemas params columns

298+ -> Query schema params columns

386− -> Query outer commons schemas params columns

299+ -> Query schema params columns

387q1 `unionAll` q2 = UnsafeQuery $

300q1 `unionAll` q2 = UnsafeQuery $

388− parenthesized (renderSQL q1)

301+ parenthesized (renderQuery q1)

389 <+> "UNION" <+> "ALL"

302 <+> "UNION" <+> "ALL"

390− <+> parenthesized (renderSQL q2)

303+ <+> parenthesized (renderQuery q2)

391

304

392-- | The results of two queries can be combined using the set operation

305-- | The results of two queries can be combined using the set operation

393-- `intersect`, the intersection. Duplicate rows are eliminated.

306-- `intersect`, the intersection. Duplicate rows are eliminated.

394intersect

307intersect

395− :: Query outer commons schemas params columns

308+ :: Query schema params columns

396− -> Query outer commons schemas params columns

309+ -> Query schema params columns

397− -> Query outer commons schemas params columns

310+ -> Query schema params columns

398q1 `intersect` q2 = UnsafeQuery $

311q1 `intersect` q2 = UnsafeQuery $

399− parenthesized (renderSQL q1)

312+ parenthesized (renderQuery q1)

400 <+> "INTERSECT"

313 <+> "INTERSECT"

401− <+> parenthesized (renderSQL q2)

314+ <+> parenthesized (renderQuery q2)

402

315

403-- | The results of two queries can be combined using the set operation

316-- | The results of two queries can be combined using the set operation

404-- `intersectAll`, the intersection. Duplicate rows are retained.

317-- `intersectAll`, the intersection. Duplicate rows are retained.

405intersectAll

318intersectAll

406− :: Query outer commons schemas params columns

319+ :: Query schema params columns

407− -> Query outer commons schemas params columns

320+ -> Query schema params columns

408− -> Query outer commons schemas params columns

321+ -> Query schema params columns

409q1 `intersectAll` q2 = UnsafeQuery $

322q1 `intersectAll` q2 = UnsafeQuery $

410− parenthesized (renderSQL q1)

323+ parenthesized (renderQuery q1)

411 <+> "INTERSECT" <+> "ALL"

324 <+> "INTERSECT" <+> "ALL"

412− <+> parenthesized (renderSQL q2)

325+ <+> parenthesized (renderQuery q2)

413

326

414-- | The results of two queries can be combined using the set operation

327-- | The results of two queries can be combined using the set operation

415-- `except`, the set difference. Duplicate rows are eliminated.

328-- `except`, the set difference. Duplicate rows are eliminated.

416except

329except

417− :: Query outer commons schemas params columns

330+ :: Query schema params columns

418− -> Query outer commons schemas params columns

331+ -> Query schema params columns

419− -> Query outer commons schemas params columns

332+ -> Query schema params columns

420q1 `except` q2 = UnsafeQuery $

333q1 `except` q2 = UnsafeQuery $

421− parenthesized (renderSQL q1)

334+ parenthesized (renderQuery q1)

422 <+> "EXCEPT"

335 <+> "EXCEPT"

423− <+> parenthesized (renderSQL q2)

336+ <+> parenthesized (renderQuery q2)

424

337

425-- | The results of two queries can be combined using the set operation

338-- | The results of two queries can be combined using the set operation

426-- `exceptAll`, the set difference. Duplicate rows are retained.

339-- `exceptAll`, the set difference. Duplicate rows are retained.

427exceptAll

340exceptAll

428− :: Query outer commons schemas params columns

341+ :: Query schema params columns

429− -> Query outer commons schemas params columns

342+ -> Query schema params columns

430− -> Query outer commons schemas params columns

343+ -> Query schema params columns

431q1 `exceptAll` q2 = UnsafeQuery $

344q1 `exceptAll` q2 = UnsafeQuery $

432− parenthesized (renderSQL q1)

345+ parenthesized (renderQuery q1)

433 <+> "EXCEPT" <+> "ALL"

346 <+> "EXCEPT" <+> "ALL"

434− <+> parenthesized (renderSQL q2)

347+ <+> parenthesized (renderQuery q2)

435

348

436{-----------------------------------------

349{-----------------------------------------

437SELECT queries

350SELECT queries

438-----------------------------------------}

351-----------------------------------------}

439

352

440−{- | The simplest kinds of `Selection` are `Star` and `DotStar` which

441−emits all columns that a `TableExpression` produces. A select `List`

442−is a list of `Expression`s. A `Selection` could be a list of

443−`WindowFunction`s `Over` `WindowDefinition`. `Additional` `Selection`s can

444−be selected with `Also`.

445−-}

446−data Selection outer commons grp schemas params from row where

447− Star

448− :: HasUnique tab from row

449− => Selection outer commons 'Ungrouped schemas params from row

450− -- ^ `HasUnique` table in the `FromClause`

451− DotStar

452− :: Has tab from row

453− => Alias tab

454− -- ^ `Has` table with `Alias`

455− -> Selection outer commons 'Ungrouped schemas params from row

456− List

457− :: SListI row

458− => NP (Aliased (Expression outer commons grp schemas params from)) row

459− -- ^ `NP` list of `Aliased` `Expression`s

460− -> Selection outer commons grp schemas params from row

461− Over

462− :: SListI row

463− => NP (Aliased (WindowFunction outer commons grp schemas params from)) row

464− -- ^ `NP` list of `Aliased` `WindowFunction`s

465− -> WindowDefinition outer commons grp schemas params from

466− -> Selection outer commons grp schemas params from row

467− Also

468− :: Selection outer commons grp schemas params from right

469− -- ^ `Additional` `Selection`

470− -> Selection outer commons grp schemas params from left

471− -> Selection outer commons grp schemas params from (Join left right)

472−instance Additional (Selection outer commons grp schemas params from) where

473− also = Also

474−instance (KnownSymbol col, row ~ '[col ::: ty])

475− => Aliasable col

476− (Expression outer commons grp schemas params from ty)

477− (Selection outer commons grp schemas params from row) where

478− expr `as` col = List (expr `as` col)

479−instance (Has tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

480− => IsQualified tab col

481− (Selection outer commons 'Ungrouped schemas params from row1) where

482− tab ! col = tab ! col `as` col

483−instance

484− ( Has tab (Join outer from) row0

485− , Has col row0 ty

486− , row1 ~ '[col ::: ty]

487− , GroupedBy tab col bys )

488− => IsQualified tab col

489− (Selection outer commons ('Grouped bys) schemas params from row1) where

490− tab ! col = tab ! col `as` col

491−instance (HasUnique tab (Join outer from) row0, Has col row0 ty, row1 ~ '[col ::: ty])

492− => IsLabel col

493− (Selection outer commons 'Ungrouped schemas params from row1) where

494− fromLabel = fromLabel @col `as` Alias

495−instance

496− ( HasUnique tab (Join outer from) row0

497− , Has col row0 ty

498− , row1 ~ '[col ::: ty]

499− , GroupedBy tab col bys )

500− => IsLabel col

501− (Selection outer commons ('Grouped bys) schemas params from row1) where

502− fromLabel = fromLabel @col `as` Alias

503−

504−instance RenderSQL (Selection outer commons grp schemas params from row) where

505− renderSQL = \case

506− List list -> renderCommaSeparated (renderAliased renderSQL) list

507− Star -> "*"

508− DotStar tab -> renderSQL tab <> ".*"

509− Also right left -> renderSQL left <> ", " <> renderSQL right

510− Over winFns winDef ->

511− let

512− renderOver

513− :: Aliased (WindowFunction outer commons grp schemas params from) field

514− -> ByteString

515− renderOver (winFn `As` col) = renderSQL winFn

516− <+> "OVER" <+> parenthesized (renderSQL winDef)

517− <+> "AS" <+> renderSQL col

518− in

519− renderCommaSeparated renderOver winFns

520−

521−instance IsString

522− (Selection outer commons grp schemas params from '["fromOnly" ::: 'NotNull 'PGtext]) where

523− fromString str = fromString str `as` Alias

524−

525-- | the `TableExpression` in the `select` command constructs an intermediate

353-- | the `TableExpression` in the `select` command constructs an intermediate

526-- virtual table by possibly combining tables, views, eliminating rows,

354-- virtual table by possibly combining tables, views, eliminating rows,

527-- grouping, etc. This table is finally passed on to processing by

355-- grouping, etc. This table is finally passed on to processing by

528−-- the select list. The `Selection` determines which columns of

356+-- the select list. The select list determines which columns of

529-- the intermediate table are actually output.

357-- the intermediate table are actually output.

530select

358select

531− :: (SListI row, row ~ (x ': xs))

359+ :: SListI columns

532− => Selection outer commons grp schemas params from row

533− -- ^ selection

534− -> TableExpression outer commons grp schemas params from

535− -- ^ intermediate virtual table

536− -> Query outer commons schemas params row

537−select selection tabexpr = UnsafeQuery $

538− "SELECT"

539− <+> renderSQL selection

540− <+> renderSQL tabexpr

541−

542−-- | Like `select` but takes an `NP` list of `Expression`s instead

543−-- of a general `Selection`.

544−select_

545− :: (SListI row, row ~ (x ': xs))

546− => NP (Aliased (Expression outer commons grp schemas params from)) row

360+ => NP (Aliased (Expression relations grouping params)) (column ': columns)

547 -- ^ select list

361 -- ^ select list

548− -> TableExpression outer commons grp schemas params from

362+ -> TableExpression schema params relations grouping

549 -- ^ intermediate virtual table

363 -- ^ intermediate virtual table

550− -> Query outer commons schemas params row

364+ -> Query schema params (column ': columns)

551−select_ = select . List

365+select list rels = UnsafeQuery $

366+ "SELECT"

367+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list

368+ <+> renderTableExpression rels

552

369

553-- | After the select list has been processed, the result table can

370-- | After the select list has been processed, the result table can

554-- be subject to the elimination of duplicate rows using `selectDistinct`.

371-- be subject to the elimination of duplicate rows using `selectDistinct`.

555selectDistinct

372selectDistinct

556− :: (SListI columns, columns ~ (col ': cols))

373+ :: SListI columns

557− => Selection outer commons grp schemas params from columns

374+ => NP (Aliased (Expression relations 'Ungrouped params)) (column ': columns)

558− -- ^ selection

375+ -- ^ select list

559− -> TableExpression outer commons grp schemas params from

376+ -> TableExpression schema params relations 'Ungrouped

560 -- ^ intermediate virtual table

377 -- ^ intermediate virtual table

561− -> Query outer commons schemas params columns

378+ -> Query schema params (column ': columns)

562−selectDistinct selection tabexpr = UnsafeQuery $

379+selectDistinct list rels = UnsafeQuery $

563 "SELECT DISTINCT"

380 "SELECT DISTINCT"

564− <+> renderSQL selection

381+ <+> renderCommaSeparated (renderAliasedAs renderExpression) list

565− <+> renderSQL tabexpr

382+ <+> renderTableExpression rels

566−

383+

567−-- | Like `selectDistinct` but takes an `NP` list of `Expression`s instead

384+-- | The simplest kind of query is `selectStar` which emits all columns

568−-- of a general `Selection`.

385+-- that the table expression produces.

569−selectDistinct_

386+selectStar

570− :: (SListI columns, columns ~ (col ': cols))

387+ :: HasUnique relation relations columns

571− => NP (Aliased (Expression outer commons grp schemas params from)) columns

572− -- ^ select list

573− -> TableExpression outer commons grp schemas params from

388+ => TableExpression schema params relations 'Ungrouped

574 -- ^ intermediate virtual table

389 -- ^ intermediate virtual table

575− -> Query outer commons schemas params columns

390+ -> Query schema params columns

576−selectDistinct_ = selectDistinct . List

391+selectStar rels = UnsafeQuery $ "SELECT" <+> "*" <+> renderTableExpression rels

577−

392+

578−{-|

393+-- | A `selectDistinctStar` emits all columns that the table expression

579−`selectDistinctOn` keeps only the first row of each set of rows where

394+-- produces and eliminates duplicate rows.

580−the given expressions evaluate to equal. The DISTINCT ON expressions are

395+selectDistinctStar

581−interpreted using the same rules as for ORDER BY. ORDER BY is used to

396+ :: HasUnique relation relations columns

582−ensure that the desired row appears first.

583−

584−The DISTINCT ON expression(s) must match the leftmost ORDER BY expression(s).

585−The ORDER BY clause will normally contain additional expression(s) that

586−determine the desired precedence of rows within each DISTINCT ON group.

587−

588−In order to guarantee they match and reduce redundancy, this function

589−will prepend the The DISTINCT ON expressions to the ORDER BY clause.

590−-}

591−selectDistinctOn

592− :: (SListI columns, columns ~ (col ': cols))

593− => [SortExpression outer commons grp schemas params from]

594− -- ^ DISTINCT ON expression(s) and prepended to ORDER BY clause

595− -> Selection outer commons grp schemas params from columns

596− -- ^ selection

597− -> TableExpression outer commons grp schemas params from

397+ => TableExpression schema params relations 'Ungrouped

598 -- ^ intermediate virtual table

398 -- ^ intermediate virtual table

599− -> Query outer commons schemas params columns

399+ -> Query schema params columns

600−selectDistinctOn distincts selection tab = UnsafeQuery $

400+selectDistinctStar rels = UnsafeQuery $

601− "SELECT DISTINCT ON"

401+ "SELECT DISTINCT" <+> "*" <+> renderTableExpression rels

602− <+> parenthesized (commaSeparated (renderDistinctOn <$> distincts))

402+

603− <+> renderSQL selection

403+-- | When working with multiple tables, it can also be useful to ask

604− <+> renderSQL (tab {orderByClause = distincts <> orderByClause tab})

404+-- for all the columns of a particular table, using `selectDotStar`.

605− where

405+selectDotStar

606− renderDistinctOn = \case

406+ :: Has relation relations columns

607− Asc expression -> renderSQL expression

407+ => Alias relation

608− Desc expression -> renderSQL expression

408+ -- ^ particular virtual subtable

609− AscNullsFirst expression -> renderSQL expression

409+ -> TableExpression schema params relations 'Ungrouped

610− DescNullsFirst expression -> renderSQL expression

410+ -- ^ intermediate virtual table

611− AscNullsLast expression -> renderSQL expression

411+ -> Query schema params columns

612− DescNullsLast expression -> renderSQL expression

412+selectDotStar rel relations = UnsafeQuery $

613−

413+ "SELECT" <+> renderAlias rel <> ".*" <+> renderTableExpression relations

614−-- | Like `selectDistinctOn` but takes an `NP` list of `Expression`s instead

414+

615−-- of a general `Selection`.

415+-- | A `selectDistinctDotStar` asks for all the columns of a particular table,

616−selectDistinctOn_

416+-- and eliminates duplicate rows.

617− :: (SListI columns, columns ~ (col ': cols))

417+selectDistinctDotStar

618− => [SortExpression outer commons grp schemas params from]

418+ :: Has relation relations columns

619− -- ^ distinct on and return the first row in ordering

419+ => Alias relation

620− -> NP (Aliased (Expression outer commons grp schemas params from)) columns

420+ -- ^ particular virtual table

621− -- ^ selection

622− -> TableExpression outer commons grp schemas params from

421+ -> TableExpression schema params relations 'Ungrouped

623 -- ^ intermediate virtual table

422 -- ^ intermediate virtual table

624− -> Query outer commons schemas params columns

423+ -> Query schema params columns

625−selectDistinctOn_ distincts = selectDistinctOn distincts . List

424+selectDistinctDotStar rel relations = UnsafeQuery $

626−

425+ "SELECT DISTINCT" <+> renderAlias rel <> ".*"

627−-- | `values` computes a row value or set of row values

426+ <+> renderTableExpression relations

628−-- specified by value expressions. It is most commonly used

427+

629−-- to generate a “constant table” within a larger command,

630−-- but it can be used on its own.

631−--

632−-- >>> type Row = '["a" ::: 'NotNull 'PGint4, "b" ::: 'NotNull 'PGtext]

633−-- >>> let query = values (1 `as` #a :* "one" `as` #b) [] :: Query outer commons schemas '[] Row

634−-- >>> printSQL query

635−-- SELECT * FROM (VALUES (1, E'one')) AS t ("a", "b")

636values

428values

637 :: SListI cols

429 :: SListI cols

638− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

430+ => NP (Aliased (Expression '[] 'Ungrouped params)) cols

639− -> [NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols]

431+ -> [NP (Aliased (Expression '[] 'Ungrouped params)) cols]

640− -- ^ When more than one row is specified, all the rows must

641− -- must have the same number of elements

642− -> Query outer commons schemas params cols

432+ -> Query schema params cols

643values rw rws = UnsafeQuery $ "SELECT * FROM"

433values rw rws = UnsafeQuery $ "SELECT * FROM"

644 <+> parenthesized (

434 <+> parenthesized (

645 "VALUES"

435 "VALUES"

@@ -650,18 +440,9 @@ values rw rws = UnsafeQuery $ "SELECT * FROM"

650 <+> parenthesized (renderCommaSeparated renderAliasPart rw)

440 <+> parenthesized (renderCommaSeparated renderAliasPart rw)

651 where

441 where

652 renderAliasPart, renderValuePart

442 renderAliasPart, renderValuePart

653− :: Aliased (Expression outer commons 'Ungrouped schemas params '[] ) ty -> ByteString

443+ :: Aliased (Expression '[] 'Ungrouped params) ty -> ByteString

654− renderAliasPart (_ `As` name) = renderSQL name

444+ renderAliasPart (_ `As` name) = renderAlias name

655− renderValuePart (value `As` _) = renderSQL value

445+ renderValuePart (value `As` _) = renderExpression value

656−

657−-- | `values_` computes a row value or set of row values

658−-- specified by value expressions.

659−values_

660− :: SListI cols

661− => NP (Aliased (Expression outer commons 'Ungrouped schemas params '[] )) cols

662− -- ^ one row of values

663− -> Query outer commons schemas params cols

664−values_ rw = values rw []

665

446

666{-----------------------------------------

447{-----------------------------------------

667Table Expressions

448Table Expressions

@@ -674,17 +455,15 @@ Table Expressions

674-- to a table on disk, a so-called base table, but more complex expressions

455-- to a table on disk, a so-called base table, but more complex expressions

675-- can be used to modify or combine base tables in various ways.

456-- can be used to modify or combine base tables in various ways.

676data TableExpression

457data TableExpression

677− (outer :: FromType)

458+ (schema :: SchemaType)

678− (commons :: FromType)

679− (grp :: Grouping)

680− (schemas :: SchemasType)

681 (params :: [NullityType])

459 (params :: [NullityType])

682− (from :: FromType)

460+ (relations :: RelationsType)

461+ (grouping :: Grouping)

683 = TableExpression

462 = TableExpression

684− { fromClause :: FromClause outer commons schemas params from

463+ { fromClause :: FromClause schema params relations

685 -- ^ A table reference that can be a table name, or a derived table such

464 -- ^ A table reference that can be a table name, or a derived table such

686 -- as a subquery, a @JOIN@ construct, or complex combinations of these.

465 -- as a subquery, a @JOIN@ construct, or complex combinations of these.

687− , whereClause :: [Condition outer commons 'Ungrouped schemas params from]

466+ , whereClause :: [Condition relations 'Ungrouped params]

688 -- ^ optional search coditions, combined with `.&&`. After the processing

467 -- ^ optional search coditions, combined with `.&&`. After the processing

689 -- of the `fromClause` is done, each row of the derived virtual table

468 -- of the `fromClause` is done, each row of the derived virtual table

690 -- is checked against the search condition. If the result of the

469 -- is checked against the search condition. If the result of the

@@ -693,20 +472,20 @@ data TableExpression

693 -- at least one column of the table generated in the `fromClause`;

472 -- at least one column of the table generated in the `fromClause`;

694 -- this is not required, but otherwise the WHERE clause will

473 -- this is not required, but otherwise the WHERE clause will

695 -- be fairly useless.

474 -- be fairly useless.

696− , groupByClause :: GroupByClause grp from

475+ , groupByClause :: GroupByClause relations grouping

697 -- ^ The `groupByClause` is used to group together those rows in a table

476 -- ^ The `groupByClause` is used to group together those rows in a table

698 -- that have the same values in all the columns listed. The order in which

477 -- that have the same values in all the columns listed. The order in which

699 -- the columns are listed does not matter. The effect is to combine each

478 -- the columns are listed does not matter. The effect is to combine each

700 -- set of rows having common values into one group row that represents all

479 -- set of rows having common values into one group row that represents all

701 -- rows in the group. This is done to eliminate redundancy in the output

480 -- rows in the group. This is done to eliminate redundancy in the output

702 -- and/or compute aggregates that apply to these groups.

481 -- and/or compute aggregates that apply to these groups.

703− , havingClause :: HavingClause outer commons grp schemas params from

482+ , havingClause :: HavingClause relations grouping params

704 -- ^ If a table has been grouped using `groupBy`, but only certain groups

483 -- ^ If a table has been grouped using `groupBy`, but only certain groups

705 -- are of interest, the `havingClause` can be used, much like a

484 -- are of interest, the `havingClause` can be used, much like a

706 -- `whereClause`, to eliminate groups from the result. Expressions in the

485 -- `whereClause`, to eliminate groups from the result. Expressions in the

707 -- `havingClause` can refer both to grouped expressions and to ungrouped

486 -- `havingClause` can refer both to grouped expressions and to ungrouped

708 -- expressions (which necessarily involve an aggregate function).

487 -- expressions (which necessarily involve an aggregate function).

709− , orderByClause :: [SortExpression outer commons grp schemas params from]

488+ , orderByClause :: [SortExpression relations grouping params]

710 -- ^ The `orderByClause` is for optional sorting. When more than one

489 -- ^ The `orderByClause` is for optional sorting. When more than one

711 -- `SortExpression` is specified, the later (right) values are used to sort

490 -- `SortExpression` is specified, the later (right) values are used to sort

712 -- rows that are equal according to the earlier (left) values.

491 -- rows that are equal according to the earlier (left) values.

@@ -716,69 +495,72 @@ data TableExpression

716 -- will be returned (but possibly fewer, if the query itself yields

495 -- will be returned (but possibly fewer, if the query itself yields

717 -- fewer rows).

496 -- fewer rows).

718 , offsetClause :: [Word64]

497 , offsetClause :: [Word64]

719− -- ^ The `offsetClause` is combined with `Prelude.+` to give an offset count

498+ -- ^ The `offsetClause` is combined with `+` to give an offset count

720 -- if nonempty. The offset count says to skip that many rows before

499 -- if nonempty. The offset count says to skip that many rows before

721 -- beginning to return rows. The rows are skipped before the limit count

500 -- beginning to return rows. The rows are skipped before the limit count

722 -- is applied.

501 -- is applied.

723− } deriving (GHC.Generic)

502+ }

724

503

725-- | Render a `TableExpression`

504-- | Render a `TableExpression`

726−instance RenderSQL (TableExpression outer commons grp schemas params from) where

505+renderTableExpression

727− renderSQL

506+ :: TableExpression schema params relations grouping

507+ -> ByteString

508+renderTableExpression

728− (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

509+ (TableExpression frm' whs' grps' hvs' srts' lims' offs') = mconcat

729− [ "FROM ", renderSQL frm'

510+ [ "FROM ", renderFromClause frm'

730− , renderWheres whs'

511+ , renderWheres whs'

731− , renderSQL grps'

512+ , renderGroupByClause grps'

732− , renderSQL hvs'

513+ , renderHavingClause hvs'

733− , renderOrderByClause srts'

514+ , renderOrderByClause srts'

734− , renderLimits lims'

515+ , renderLimits lims'

735− , renderOffsets offs' ]

516+ , renderOffsets offs'

517+ ]

736− where

518+ where

737− renderWheres = \case

519+ renderWheres = \case

738− [] -> ""

520+ [] -> ""

739− wh:[] -> " WHERE" <+> renderSQL wh

521+ wh:[] -> " WHERE" <+> renderExpression wh

740− wh:whs -> " WHERE" <+> renderSQL (foldr (.&&) wh whs)

522+ wh:whs -> " WHERE" <+> renderExpression (foldr (.&&) wh whs)

741− renderOrderByClause = \case

523+ renderOrderByClause = \case

742− [] -> ""

524+ [] -> ""

743− srts -> " ORDER BY"

525+ srts -> " ORDER BY"

744− <+> commaSeparated (renderSQL <$> srts)

526+ <+> commaSeparated (renderSortExpression <$> srts)

745− renderLimits = \case

527+ renderLimits = \case

746− [] -> ""

528+ [] -> ""

747− lims -> " LIMIT" <+> fromString (show (minimum lims))

529+ lims -> " LIMIT" <+> fromString (show (minimum lims))

748− renderOffsets = \case

530+ renderOffsets = \case

749− [] -> ""

531+ [] -> ""

750− offs -> " OFFSET" <+> fromString (show (sum offs))

532+ offs -> " OFFSET" <+> fromString (show (sum offs))

751

533

752-- | A `from` generates a `TableExpression` from a table reference that can be

534-- | A `from` generates a `TableExpression` from a table reference that can be

753-- a table name, or a derived table such as a subquery, a JOIN construct,

535-- a table name, or a derived table such as a subquery, a JOIN construct,

754-- or complex combinations of these. A `from` may be transformed by `where_`,

536-- or complex combinations of these. A `from` may be transformed by `where_`,

755−-- `groupBy`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

537+-- `group`, `having`, `orderBy`, `limit` and `offset`, using the `&` operator

756-- to match the left-to-right sequencing of their placement in SQL.

538-- to match the left-to-right sequencing of their placement in SQL.

757from

539from

758− :: FromClause outer commons schemas params from -- ^ table reference

540+ :: FromClause schema params relations -- ^ table reference

759− -> TableExpression outer commons 'Ungrouped schemas params from

541+ -> TableExpression schema params relations 'Ungrouped

760−from tab = TableExpression tab [] noGroups NoHaving [] [] []

542+from rels = TableExpression rels [] NoGroups NoHaving [] [] []

761

543

762-- | A `where_` is an endomorphism of `TableExpression`s which adds a

544-- | A `where_` is an endomorphism of `TableExpression`s which adds a

763-- search condition to the `whereClause`.

545-- search condition to the `whereClause`.

764where_

546where_

765− :: Condition outer commons 'Ungrouped schemas params from -- ^ filtering condition

547+ :: Condition relations 'Ungrouped params -- ^ filtering condition

766− -> TableExpression outer commons grp schemas params from

548+ -> TableExpression schema params relations grouping

767− -> TableExpression outer commons grp schemas params from

549+ -> TableExpression schema params relations grouping

768where_ wh rels = rels {whereClause = wh : whereClause rels}

550where_ wh rels = rels {whereClause = wh : whereClause rels}

769

551

770−-- | A `groupBy` is a transformation of `TableExpression`s which switches

552+-- | A `group` is a transformation of `TableExpression`s which switches

771−-- its `Grouping` from `Ungrouped` to `Grouped`. Use @groupBy Nil@ to perform

553+-- its `Grouping` from `Ungrouped` to `Grouped`. Use @group Nil@ to perform

772-- a "grand total" aggregation query.

554-- a "grand total" aggregation query.

773−groupBy

555+group

774 :: SListI bys

556 :: SListI bys

775− => NP (By from) bys -- ^ grouped columns

557+ => NP (By relations) bys -- ^ grouped columns

776− -> TableExpression outer commons 'Ungrouped schemas params from

558+ -> TableExpression schema params relations 'Ungrouped

777− -> TableExpression outer commons ('Grouped bys) schemas params from

559+ -> TableExpression schema params relations ('Grouped bys)

778−groupBy bys rels = TableExpression

560+group bys rels = TableExpression

779 { fromClause = fromClause rels

561 { fromClause = fromClause rels

780 , whereClause = whereClause rels

562 , whereClause = whereClause rels

781− , groupByClause = group bys

563+ , groupByClause = Group bys

782 , havingClause = Having []

564 , havingClause = Having []

783 , orderByClause = []

565 , orderByClause = []

784 , limitClause = limitClause rels

566 , limitClause = limitClause rels

@@ -788,29 +570,34 @@ groupBy bys rels = TableExpression

788-- | A `having` is an endomorphism of `TableExpression`s which adds a

570-- | A `having` is an endomorphism of `TableExpression`s which adds a

789-- search condition to the `havingClause`.

571-- search condition to the `havingClause`.

790having

572having

791− :: Condition outer commons ('Grouped bys) schemas params from -- ^ having condition

573+ :: Condition relations ('Grouped bys) params -- ^ having condition

792− -> TableExpression outer commons ('Grouped bys) schemas params from

574+ -> TableExpression schema params relations ('Grouped bys)

793− -> TableExpression outer commons ('Grouped bys) schemas params from

575+ -> TableExpression schema params relations ('Grouped bys)

794having hv rels = rels

576having hv rels = rels

795 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }

577 { havingClause = case havingClause rels of Having hvs -> Having (hv:hvs) }

796

578

797−instance OrderBy TableExpression where

579+-- | An `orderBy` is an endomorphism of `TableExpression`s which appends an

580+-- ordering to the right of the `orderByClause`.

581+orderBy

582+ :: [SortExpression relations grouping params] -- ^ sort expressions

583+ -> TableExpression schema params relations grouping

584+ -> TableExpression schema params relations grouping

798− orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

585+orderBy srts rels = rels {orderByClause = orderByClause rels ++ srts}

799

586

800-- | A `limit` is an endomorphism of `TableExpression`s which adds to the

587-- | A `limit` is an endomorphism of `TableExpression`s which adds to the

801-- `limitClause`.

588-- `limitClause`.

802limit

589limit

803 :: Word64 -- ^ limit parameter

590 :: Word64 -- ^ limit parameter

804− -> TableExpression outer commons grp schemas params from

591+ -> TableExpression schema params relations grouping

805− -> TableExpression outer commons grp schemas params from

592+ -> TableExpression schema params relations grouping

806limit lim rels = rels {limitClause = lim : limitClause rels}

593limit lim rels = rels {limitClause = lim : limitClause rels}

807

594

808-- | An `offset` is an endomorphism of `TableExpression`s which adds to the

595-- | An `offset` is an endomorphism of `TableExpression`s which adds to the

809-- `offsetClause`.

596-- `offsetClause`.

810offset

597offset

811 :: Word64 -- ^ offset parameter

598 :: Word64 -- ^ offset parameter

812− -> TableExpression outer commons grp schemas params from

599+ -> TableExpression schema params relations grouping

813− -> TableExpression outer commons grp schemas params from

600+ -> TableExpression schema params relations grouping

814offset off rels = rels {offsetClause = off : offsetClause rels}

601offset off rels = rels {offsetClause = off : offsetClause rels}

815

602

816{-----------------------------------------

603{-----------------------------------------

@@ -821,76 +608,57 @@ FROM clauses

821A `FromClause` can be a table name, or a derived table such

608A `FromClause` can be a table name, or a derived table such

822as a subquery, a @JOIN@ construct, or complex combinations of these.

609as a subquery, a @JOIN@ construct, or complex combinations of these.

823-}

610-}

824−newtype FromClause outer commons schemas params from

611+newtype FromClause schema params relations

825 = UnsafeFromClause { renderFromClause :: ByteString }

612 = UnsafeFromClause { renderFromClause :: ByteString }

826 deriving (GHC.Generic,Show,Eq,Ord,NFData)

613 deriving (GHC.Generic,Show,Eq,Ord,NFData)

827−instance RenderSQL (FromClause outer commons schemas params from) where

828− renderSQL = renderFromClause

829

614

830−-- | A real `table` is a table from the database.

615+-- | A real `table` is a table from the schema.

831table

616table

832− :: (Has sch schemas schema, Has tab schema ('Table table))

617+ :: Aliased (Table schema) table

833− => Aliased (QualifiedAlias sch) (alias ::: tab)

834− -> FromClause outer commons schemas params '[alias ::: TableToRow table]

618+ -> FromClause schema params '[table]

835−table (tab `As` alias) = UnsafeFromClause $

619+table = UnsafeFromClause . renderAliasedAs renderTable

836− renderSQL tab <+> "AS" <+> renderSQL alias

837

620

838-- | `subquery` derives a table from a `Query`.

621-- | `subquery` derives a table from a `Query`.

839subquery

622subquery

840− :: Aliased (Query outer commons schemas params) query

623+ :: Aliased (Query schema params) table

841− -> FromClause outer commons schemas params '[query]

624+ -> FromClause schema params '[table]

842−subquery = UnsafeFromClause . renderAliased (parenthesized . renderSQL)

625+subquery = UnsafeFromClause . renderAliasedAs (parenthesized . renderQuery)

843

626

844-- | `view` derives a table from a `View`.

627-- | `view` derives a table from a `View`.

845view

628view

846− :: (Has sch schemas schema, Has vw schema ('View view))

629+ :: Aliased (View schema) table

847− => Aliased (QualifiedAlias sch) (alias ::: vw)

848− -> FromClause outer commons schemas params '[alias ::: view]

630+ -> FromClause schema params '[table]

849−view (vw `As` alias) = UnsafeFromClause $

631+view = UnsafeFromClause . renderAliasedAs renderView

850− renderSQL vw <+> "AS" <+> renderSQL alias

632+

851−

852−-- | `common` derives a table from a common table expression.

853−common

854− :: Has cte commons common

855− => Aliased Alias (alias ::: cte)

856− -> FromClause outer commons schemas params '[alias ::: common]

857−common (cte `As` alias) = UnsafeFromClause $

858− renderSQL cte <+> "AS" <+> renderSQL alias

859−

860−instance Additional (FromClause outer commons schemas params) where

861− also right left = UnsafeFromClause $

862− renderSQL left <> ", " <> renderSQL right

863−

864−{- |

865−@left & crossJoin right@. For every possible combination of rows from

633+{- | @left & crossJoin right@. For every possible combination of rows from

866−@left@ and @right@ (i.e., a Cartesian product), the joined table will contain

634+ @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@.

635+ 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

636+ If the tables have @n@ and @m@ rows respectively, the joined table will

869−have @n * m@ rows.

637+ have @n * m@ rows.

870-}

638-}

871crossJoin

639crossJoin

872− :: FromClause outer commons schemas params right

640+ :: FromClause schema params right

873 -- ^ right

641 -- ^ right

874− -> FromClause outer commons schemas params left

642+ -> FromClause schema params left

875 -- ^ left

643 -- ^ left

876− -> FromClause outer commons schemas params (Join left right)

644+ -> FromClause schema params (Join left right)

877crossJoin right left = UnsafeFromClause $

645crossJoin right left = UnsafeFromClause $

878− renderSQL left <+> "CROSS JOIN" <+> renderSQL right

646+ renderFromClause left <+> "CROSS JOIN" <+> renderFromClause right

879

647

880{- | @left & innerJoin right on@. The joined table is filtered by

648{- | @left & innerJoin right on@. The joined table is filtered by

881the @on@ condition.

649the @on@ condition.

882-}

650-}

883innerJoin

651innerJoin

884− :: FromClause outer commons schemas params right

652+ :: FromClause schema params right

885 -- ^ right

653 -- ^ right

886− -> Condition outer commons 'Ungrouped schemas params (Join left right)

654+ -> Condition (Join left right) 'Ungrouped params

887 -- ^ @on@ condition

655 -- ^ @on@ condition

888− -> FromClause outer commons schemas params left

656+ -> FromClause schema params left

889 -- ^ left

657 -- ^ left

890− -> FromClause outer commons schemas params (Join left right)

658+ -> FromClause schema params (Join left right)

891innerJoin right on left = UnsafeFromClause $

659innerJoin right on left = UnsafeFromClause $

892− renderSQL left <+> "INNER JOIN" <+> renderSQL right

660+ renderFromClause left <+> "INNER JOIN" <+> renderFromClause right

893− <+> "ON" <+> renderSQL on

661+ <+> "ON" <+> renderExpression on

894

662

895{- | @left & leftOuterJoin right on@. First, an inner join is performed.

663{- | @left & leftOuterJoin right on@. First, an inner join is performed.

896 Then, for each row in @left@ that does not satisfy the @on@ condition with

664 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -898,16 +666,16 @@ innerJoin right on left = UnsafeFromClause $

898 Thus, the joined table always has at least one row for each row in @left@.

666 Thus, the joined table always has at least one row for each row in @left@.

899-}

667-}

900leftOuterJoin

668leftOuterJoin

901− :: FromClause outer commons schemas params right

669+ :: FromClause schema params right

902 -- ^ right

670 -- ^ right

903− -> Condition outer commons 'Ungrouped schemas params (Join left right)

671+ -> Condition (Join left right) 'Ungrouped params

904 -- ^ @on@ condition

672 -- ^ @on@ condition

905− -> FromClause outer commons schemas params left

673+ -> FromClause schema params left

906 -- ^ left

674 -- ^ left

907− -> FromClause outer commons schemas params (Join left (NullifyFrom right))

675+ -> FromClause schema params (Join left (NullifyRelations right))

908leftOuterJoin right on left = UnsafeFromClause $

676leftOuterJoin right on left = UnsafeFromClause $

909− renderSQL left <+> "LEFT OUTER JOIN" <+> renderSQL right

677+ renderFromClause left <+> "LEFT OUTER JOIN" <+> renderFromClause right

910− <+> "ON" <+> renderSQL on

678+ <+> "ON" <+> renderExpression on

911

679

912{- | @left & rightOuterJoin right on@. First, an inner join is performed.

680{- | @left & rightOuterJoin right on@. First, an inner join is performed.

913 Then, for each row in @right@ that does not satisfy the @on@ condition with

681 Then, for each row in @right@ that does not satisfy the @on@ condition with

@@ -916,16 +684,16 @@ leftOuterJoin right on left = UnsafeFromClause $

916 have a row for each row in @right@.

684 have a row for each row in @right@.

917-}

685-}

918rightOuterJoin

686rightOuterJoin

919− :: FromClause outer commons schemas params right

687+ :: FromClause schema params right

920 -- ^ right

688 -- ^ right

921− -> Condition outer commons 'Ungrouped schemas params (Join left right)

689+ -> Condition (Join left right) 'Ungrouped params

922 -- ^ @on@ condition

690 -- ^ @on@ condition

923− -> FromClause outer commons schemas params left

691+ -> FromClause schema params left

924 -- ^ left

692 -- ^ left

925− -> FromClause outer commons schemas params (Join (NullifyFrom left) right)

693+ -> FromClause schema params (Join (NullifyRelations left) right)

926rightOuterJoin right on left = UnsafeFromClause $

694rightOuterJoin right on left = UnsafeFromClause $

927− renderSQL left <+> "RIGHT OUTER JOIN" <+> renderSQL right

695+ renderFromClause left <+> "RIGHT OUTER JOIN" <+> renderFromClause right

928− <+> "ON" <+> renderSQL on

696+ <+> "ON" <+> renderExpression on

929

697

930{- | @left & fullOuterJoin right on@. First, an inner join is performed.

698{- | @left & fullOuterJoin right on@. First, an inner join is performed.

931 Then, for each row in @left@ that does not satisfy the @on@ condition with

699 Then, for each row in @left@ that does not satisfy the @on@ condition with

@@ -935,56 +703,47 @@ rightOuterJoin right on left = UnsafeFromClause $

935 is added.

703 is added.

936-}

704-}

937fullOuterJoin

705fullOuterJoin

938− :: FromClause outer commons schemas params right

706+ :: FromClause schema params right

939 -- ^ right

707 -- ^ right

940− -> Condition outer commons 'Ungrouped schemas params (Join left right)

708+ -> Condition (Join left right) 'Ungrouped params

941 -- ^ @on@ condition

709 -- ^ @on@ condition

942− -> FromClause outer commons schemas params left

710+ -> FromClause schema params left

943 -- ^ left

711 -- ^ left

944− -> FromClause outer commons schemas params

712+ -> FromClause schema params

945− (Join (NullifyFrom left) (NullifyFrom right))

713+ (Join (NullifyRelations left) (NullifyRelations right))

946fullOuterJoin right on left = UnsafeFromClause $

714fullOuterJoin right on left = UnsafeFromClause $

947− renderSQL left <+> "FULL OUTER JOIN" <+> renderSQL right

715+ renderFromClause left <+> "FULL OUTER JOIN" <+> renderFromClause right

948− <+> "ON" <+> renderSQL on

716+ <+> "ON" <+> renderExpression on

949

717

950{-----------------------------------------

718{-----------------------------------------

951Grouping

719Grouping

952-----------------------------------------}

720-----------------------------------------}

953

721

954−-- | `By`s are used in `groupBy` to reference a list of columns which are then

722+-- | `By`s are used in `group` to reference a list of columns which are then

955-- used to group together those rows in a table that have the same values

723-- used to group together those rows in a table that have the same values

956-- in all the columns listed. @By \#col@ will reference an unambiguous

724-- in all the columns listed. @By \#col@ will reference an unambiguous

957-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table

725-- column @col@; otherwise @By2 (\#tab \! \#col)@ will reference a table

958-- qualified column @tab.col@.

726-- qualified column @tab.col@.

959data By

727data By

960− (from :: FromType)

728+ (relations :: RelationsType)

961 (by :: (Symbol,Symbol)) where

729 (by :: (Symbol,Symbol)) where

962− By1

730+ By

963− :: (HasUnique table from columns, Has column columns ty)

731+ :: (HasUnique relation relations columns, Has column columns ty)

964 => Alias column

732 => Alias column

965− -> By from '(table, column)

733+ -> By relations '(relation, column)

966 By2

734 By2

967− :: (Has table from columns, Has column columns ty)

735+ :: (Has relation relations columns, Has column columns ty)

968− => Alias table

969− -> Alias column

736+ => (Alias relation, Alias column)

970− -> By from '(table, column)

737+ -> By relations '(relation, column)

971−deriving instance Show (By from by)

738+deriving instance Show (By relations by)

972−deriving instance Eq (By from by)

739+deriving instance Eq (By relations by)

973−deriving instance Ord (By from by)

740+deriving instance Ord (By relations by)

974−instance RenderSQL (By from by) where

741+

975− renderSQL = \case

742+-- | Renders a `By`.

743+renderBy :: By relations by -> ByteString

744+renderBy = \case

976− By1 column -> renderSQL column

745+ By column -> renderAlias column

977− By2 rel column -> renderSQL rel <> "." <> renderSQL column

746+ By2 (rel, column) -> renderAlias rel <> "." <> renderAlias column

978−

979−instance (HasUnique rel rels cols, Has col cols ty, by ~ '(rel, col))

980− => IsLabel col (By rels by) where fromLabel = By1 fromLabel

981−instance (HasUnique rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])

982− => IsLabel col (NP (By rels) bys) where fromLabel = By1 fromLabel :* Nil

983−instance (Has rel rels cols, Has col cols ty, by ~ '(rel, col))

984− => IsQualified rel col (By rels by) where (!) = By2

985−instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])

986− => IsQualified rel col (NP (By rels) bys) where

987− rel ! col = By2 rel col :* Nil

988

747

989-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.

748-- | A `GroupByClause` indicates the `Grouping` of a `TableExpression`.

990-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.

749-- A `NoGroups` indicates `Ungrouped` while a `Group` indicates `Grouped`.

@@ -992,107 +751,82 @@ instance (Has rel rels cols, Has col cols ty, bys ~ '[ '(rel, col)])

992-- done on @NoGroups@ while all output `Expression`s must be aggregated

751-- done on @NoGroups@ while all output `Expression`s must be aggregated

993-- in @Group Nil@. In general, all output `Expression`s in the

752-- in @Group Nil@. In general, all output `Expression`s in the

994-- complement of @bys@ must be aggregated in @Group bys@.

753-- complement of @bys@ must be aggregated in @Group bys@.

995−newtype GroupByClause grp from = UnsafeGroupByClause

754+data GroupByClause relations grouping where

996− { renderGroupByClause :: ByteString }

997− deriving (GHC.Generic,Show,Eq,Ord,NFData)

998−instance RenderSQL (GroupByClause grp from) where

999− renderSQL = renderGroupByClause

1000−noGroups :: GroupByClause 'Ungrouped from

755+ NoGroups :: GroupByClause relations 'Ungrouped

1001−noGroups = UnsafeGroupByClause ""

756+ Group

1002−group

1003− :: SListI bys

757+ :: SListI bys

1004− => NP (By from) bys

758+ => NP (By relations) bys

1005− -> GroupByClause ('Grouped bys) from

759+ -> GroupByClause relations ('Grouped bys)

1006−group bys = UnsafeGroupByClause $ case bys of

760+

761+-- | Renders a `GroupByClause`.

762+renderGroupByClause :: GroupByClause relations grouping -> ByteString

763+renderGroupByClause = \case

764+ NoGroups -> ""

1007− Nil -> ""

765+ Group Nil -> ""

1008− bys' -> " GROUP BY" <+> renderCommaSeparated renderSQL bys'

766+ Group bys -> " GROUP BY" <+> renderCommaSeparated renderBy bys

1009

767

1010-- | A `HavingClause` is used to eliminate groups that are not of interest.

768-- | A `HavingClause` is used to eliminate groups that are not of interest.

1011-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`

769-- An `Ungrouped` `TableExpression` may only use `NoHaving` while a `Grouped`

1012-- `TableExpression` must use `Having` whose conditions are combined with

770-- `TableExpression` must use `Having` whose conditions are combined with

1013-- `.&&`.

771-- `.&&`.

1014−data HavingClause outer commons grp schemas params from where

772+data HavingClause relations grouping params where

1015− NoHaving :: HavingClause outer commons 'Ungrouped schemas params from

773+ NoHaving :: HavingClause relations 'Ungrouped params

1016 Having

774 Having

1017− :: [Condition outer commons ('Grouped bys) schemas params from]

775+ :: [Condition relations ('Grouped bys) params]

1018− -> HavingClause outer commons ('Grouped bys) schemas params from

776+ -> HavingClause relations ('Grouped bys) params

1019−deriving instance Show (HavingClause outer commons grp schemas params from)

777+deriving instance Show (HavingClause relations grouping params)

1020−deriving instance Eq (HavingClause outer commons grp schemas params from)

778+deriving instance Eq (HavingClause relations grouping params)

1021−deriving instance Ord (HavingClause outer commons grp schemas params from)

779+deriving instance Ord (HavingClause relations grouping params)

1022

780

1023-- | Render a `HavingClause`.

781-- | Render a `HavingClause`.

1024−instance RenderSQL (HavingClause outer commons grp schemas params from) where

782+renderHavingClause :: HavingClause relations grouping params -> ByteString

1025− renderSQL = \case

783+renderHavingClause = \case

1026− NoHaving -> ""

784+ NoHaving -> ""

1027− Having [] -> ""

785+ Having [] -> ""

1028− Having conditions ->

786+ Having conditions ->

1029− " HAVING" <+> commaSeparated (renderSQL <$> conditions)

787+ " HAVING" <+> commaSeparated (renderExpression <$> conditions)

1030−

1031−-- | A `CommonTableExpression` is an auxiliary statement in a `with` clause.

1032−data CommonTableExpression statement

1033− (schemas :: SchemasType)

1034− (params :: [NullityType])

1035− (commons0 :: FromType)

1036− (commons1 :: FromType) where

1037− CommonTableExpression

1038− :: Aliased (statement commons schemas params) (cte ::: common)

1039− -> CommonTableExpression statement schemas params commons (cte ::: common ': commons)

1040−instance

1041− ( KnownSymbol cte

1042− , commons1 ~ (cte ::: common ': commons)

1043− ) => Aliasable cte

1044− (statement commons schemas params common)

1045− (CommonTableExpression statement schemas params commons commons1) where

1046− statement `as` cte = CommonTableExpression (statement `as` cte)

1047−instance

1048− ( KnownSymbol cte

1049− , commons1 ~ (cte ::: common ': commons)

1050− ) => Aliasable cte

1051− (statement commons schemas params common)

1052− (Path (CommonTableExpression statement schemas params) commons commons1) where

1053− statement `as` cte = csingleton (statement `as` cte)

1054−

1055−instance (forall c s p r. RenderSQL (statement c s p r)) => RenderSQL

1056− (CommonTableExpression statement schemas params commons0 commons1) where

1057− renderSQL (CommonTableExpression (statement `As` cte)) =

1058− renderSQL cte <+> "AS" <+> parenthesized (renderSQL statement)

1059−

1060−-- | `with` provides a way to write auxiliary statements for use in a larger query.

1061−-- These statements, referred to as `CommonTableExpression`s, can be thought of as

1062−-- defining temporary tables that exist just for one query.

1063−class With statement where

1064− with

1065− :: Path (CommonTableExpression statement schemas params) commons0 commons1

1066− -- ^ common table expressions

1067− -> statement commons1 schemas params row

1068− -- ^ larger query

1069− -> statement commons0 schemas params row

1070−instance With (Query outer) where

1071− with Done query = query

1072− with ctes query = UnsafeQuery $

1073− "WITH" <+> commaSeparated (ctoList renderSQL ctes) <+> renderSQL query

1074

788

1075−{- |

789+{-----------------------------------------

1076−>>> import Data.Monoid (Sum (..))

790+Sorting

1077−>>> import Data.Int (Int64)

791+-----------------------------------------}

1078−>>> :{

792+

1079− let

793+-- | `SortExpression`s are used by `sortBy` to optionally sort the results

1080− query :: Query_ schema () (Sum Int64)

794+-- of a `Query`. `Asc` or `Desc` set the sort direction of a `NotNull` result

1081− query = withRecursive

795+-- column to ascending or descending. Ascending order puts smaller values

1082− ( values_ ((1 & astype int) `as` #n)

796+-- first, where "smaller" is defined in terms of the `.<` operator. Similarly,

1083− `unionAll`

797+-- descending order is determined with the `.>` operator. `AscNullsFirst`,

1084− select_ ((#n + 1) `as` #n)

798+-- `AscNullsLast`, `DescNullsFirst` and `DescNullsLast` options are used to

1085− (from (common #t) & where_ (#n .< 100)) `as` #t )

799+-- determine whether nulls appear before or after non-null values in the sort

1086− ( select_ (fromNull 0 (sum_ (All #n)) `as` #getSum) (from (common #t) & groupBy Nil))

800+-- ordering of a `Null` result column.

1087− in printSQL query

801+data SortExpression relations grouping params where

1088−:}

802+ Asc

1089−WITH RECURSIVE "t" AS ((SELECT * FROM (VALUES ((1 :: int))) AS t ("n")) UNION ALL (SELECT ("n" + 1) AS "n" FROM "t" AS "t" WHERE ("n" < 100))) SELECT COALESCE(sum(ALL "n"), 0) AS "getSum" FROM "t" AS "t"

803+ :: Expression relations grouping params ('NotNull ty)

1090−-}

804+ -> SortExpression relations grouping params

1091−withRecursive

805+ Desc

1092− :: Aliased (Query outer (recursive ': commons) schemas params) recursive

806+ :: Expression relations grouping params ('NotNull ty)

1093− -> Query outer (recursive ': commons) schemas params row

807+ -> SortExpression relations grouping params

1094− -> Query outer commons schemas params row

808+ AscNullsFirst

1095−withRecursive (recursive `As` cte) query = UnsafeQuery $

809+ :: Expression relations grouping params ('Null ty)

1096− "WITH RECURSIVE" <+> renderSQL cte

810+ -> SortExpression relations grouping params

1097− <+> "AS" <+> parenthesized (renderSQL recursive)

811+ AscNullsLast

1098− <+> renderSQL query

812+ :: Expression relations grouping params ('Null ty)

813+ -> SortExpression relations grouping params

814+ DescNullsFirst

815+ :: Expression relations grouping params ('Null ty)

816+ -> SortExpression relations grouping params

817+ DescNullsLast

818+ :: Expression relations grouping params ('Null ty)

819+ -> SortExpression relations grouping params

820+deriving instance Show (SortExpression relations grouping params)

821+

822+-- | Render a `SortExpression`.

823+renderSortExpression :: SortExpression relations grouping params -> ByteString

824+renderSortExpression = \case

825+ Asc expression -> renderExpression expression <+> "ASC"

826+ Desc expression -> renderExpression expression <+> "DESC"

827+ AscNullsFirst expression -> renderExpression expression

828+ <+> "ASC NULLS FIRST"

829+ DescNullsFirst expression -> renderExpression expression

830+ <+> "DESC NULLS FIRST"

831+ AscNullsLast expression -> renderExpression expression <+> "ASC NULLS LAST"

832+ DescNullsLast expression -> renderExpression expression <+> "DESC NULLS LAST"

squeal-postgresql/src/Squeal/PostgreSQL/Render.hs+6−72

@@ -9,62 +9,39 @@ Rendering helper functions.

9-}

11{-# LANGUAGE

12− AllowAmbiguousTypes

13− , ConstraintKinds

14− , FlexibleContexts

15− , LambdaCase

16− , MagicHash

12+ MagicHash

17 , OverloadedStrings

13 , OverloadedStrings

18 , PolyKinds

14 , PolyKinds

19 , RankNTypes

15 , RankNTypes

20 , ScopedTypeVariables

16 , ScopedTypeVariables

21− , TypeApplications

22#-}

17#-}

24module Squeal.PostgreSQL.Render

19module Squeal.PostgreSQL.Render

25 ( -- * Render

20 ( -- * Render

26− RenderSQL (..)

27− , printSQL

28− , escape

29− , parenthesized

21+ parenthesized

30− , bracketed

31 , (<+>)

22 , (<+>)

32 , commaSeparated

23 , commaSeparated

33 , doubleQuoted

24 , doubleQuoted

34− , singleQuotedText

35− , singleQuotedUtf8

36 , renderCommaSeparated

25 , renderCommaSeparated

37− , renderCommaSeparatedConstraint

38 , renderCommaSeparatedMaybe

26 , renderCommaSeparatedMaybe

39 , renderNat

27 , renderNat

40− , renderSymbol

41 ) where

28 ) where

43−import Control.Monad.IO.Class (MonadIO (..))

44import Data.ByteString (ByteString)

30import Data.ByteString (ByteString)

45−import Data.Maybe (catMaybes)

31+import Data.Maybe

46import Data.Monoid ((<>))

32import Data.Monoid ((<>))

47−import Data.Text (Text)

48import Generics.SOP

33import Generics.SOP

49import GHC.Exts

34import GHC.Exts

50−import GHC.TypeLits hiding (Text)

35+import GHC.TypeLits

52−import qualified Data.Text as Text

53−import qualified Data.Text.Encoding as Text

54import qualified Data.ByteString as ByteString

37import qualified Data.ByteString as ByteString

55−import qualified Data.ByteString.Char8 as Char8

57-- | Parenthesize a `ByteString`.

39-- | Parenthesize a `ByteString`.

58parenthesized :: ByteString -> ByteString

40parenthesized :: ByteString -> ByteString

59parenthesized str = "(" <> str <> ")"

41parenthesized str = "(" <> str <> ")"

61−-- | Square bracket a `ByteString`

62−bracketed :: ByteString -> ByteString

63−bracketed str = "[" <> str <> "]"

64−

65-- | Concatenate two `ByteString`s with a space between.

43-- | Concatenate two `ByteString`s with a space between.

66(<+>) :: ByteString -> ByteString -> ByteString

44(<+>) :: ByteString -> ByteString -> ByteString

67−infixr 7 <+>

68str1 <+> str2 = str1 <> " " <> str2

45str1 <+> str2 = str1 <> " " <> str2

70-- | Comma separate a list of `ByteString`s.

47-- | Comma separate a list of `ByteString`s.

@@ -75,15 +52,6 @@ commaSeparated = ByteString.intercalate ", "

75doubleQuoted :: ByteString -> ByteString

52doubleQuoted :: ByteString -> ByteString

76doubleQuoted str = "\"" <> str <> "\""

53doubleQuoted str = "\"" <> str <> "\""

78−-- | Add single quotes around a `Text` and escape single quotes within it.

79−singleQuotedText :: Text -> ByteString

80−singleQuotedText str =

81− "'" <> Text.encodeUtf8 (Text.replace "'" "''" str) <> "'"

82−

83−-- | Add single quotes around a `ByteString` and escape single quotes within it.

84−singleQuotedUtf8 :: ByteString -> ByteString

85−singleQuotedUtf8 = singleQuotedText . Text.decodeUtf8

86−

87-- | Comma separate the renderings of a heterogeneous list.

55-- | Comma separate the renderings of a heterogeneous list.

88renderCommaSeparated

56renderCommaSeparated

89 :: SListI xs

57 :: SListI xs

@@ -94,16 +62,6 @@ renderCommaSeparated render

94 . hcollapse

62 . hcollapse

95 . hmap (K . render)

63 . hmap (K . render)

97−-- | Comma separate the renderings of a heterogeneous list.

98−renderCommaSeparatedConstraint

99− :: forall c xs expression. (All c xs, SListI xs)

100− => (forall x. c x => expression x -> ByteString)

101− -> NP expression xs -> ByteString

102−renderCommaSeparatedConstraint render

103− = commaSeparated

104− . hcollapse

105− . hcmap (Proxy @c) (K . render)

106−

107-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping

65-- | Comma separate the `Maybe` renderings of a heterogeneous list, dropping

108-- `Nothing`s.

66-- `Nothing`s.

109renderCommaSeparatedMaybe

67renderCommaSeparatedMaybe

@@ -117,29 +75,5 @@ renderCommaSeparatedMaybe render

117 . hmap (K . render)

75 . hmap (K . render)

118

119-- | Render a promoted `Nat`.

77-- | Render a promoted `Nat`.

120−renderNat :: forall n. KnownNat n => ByteString

78+renderNat :: KnownNat n => proxy n -> ByteString

121−renderNat = fromString (show (natVal' (proxy# :: Proxy# n)))

79+renderNat (_ :: proxy n) = fromString (show (natVal' (proxy# :: Proxy# n)))

122−

123−-- | Render a promoted `Symbol`.

124−renderSymbol :: forall s. KnownSymbol s => ByteString

125−renderSymbol = fromString (symbolVal' (proxy# :: Proxy# s))

126−

127−-- | A class for rendering SQL

128−class RenderSQL sql where renderSQL :: sql -> ByteString

129−

130−-- | Print SQL.

131−printSQL :: (RenderSQL sql, MonadIO io) => sql -> io ()

132−printSQL = liftIO . Char8.putStrLn . renderSQL

133−

134−-- | `escape` a character to prevent injection

135−escape :: Char -> String

136−escape = \case

137− '\NUL' -> "\\0"

138− '\'' -> "''"

139− '"' -> "\\\""

140− '\b' -> "\\b"

141− '\n' -> "\\n"

142− '\r' -> "\\r"

143− '\t' -> "\\t"

144− '\\' -> "\\\\"

145− c -> [c]

squeal-postgresql/src/Squeal/PostgreSQL/Schema.hs+394−335

@@ -1,15 +1,13 @@

1{-|

2Module: Squeal.PostgreSQL.Schema

3Description: Embedding of PostgreSQL type and alias system

4−Copyright: (c) Eitan Chatav, 2019

4+Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

8−`Squeal.PostgreSQL.Schema` provides a type-level DSL for kinds of Postgres types,

8+A type-level DSL for kinds of PostgreSQL types, constraints, and aliases.

9−tables, schema, constraints, aliases, enumerated labels, and groupings.

10−It also defines useful type families to operate on these. Finally,

11−it defines an embedding of Haskell types into Postgres types.

12-}

9-}

10+

13{-# LANGUAGE

11{-# LANGUAGE

14 AllowAmbiguousTypes

12 AllowAmbiguousTypes

15 , ConstraintKinds

13 , ConstraintKinds

@@ -19,9 +17,7 @@ it defines an embedding of Haskell types into Postgres types.

19 , FlexibleInstances

17 , FlexibleInstances

20 , FunctionalDependencies

18 , FunctionalDependencies

21 , GADTs

19 , GADTs

22− , LambdaCase

23 , OverloadedStrings

20 , OverloadedStrings

24− , QuantifiedConstraints

25 , RankNTypes

21 , RankNTypes

26 , ScopedTypeVariables

22 , ScopedTypeVariables

27 , StandaloneDeriving

23 , StandaloneDeriving

@@ -34,85 +30,102 @@ it defines an embedding of Haskell types into Postgres types.

34#-}

30#-}

36module Squeal.PostgreSQL.Schema

32module Squeal.PostgreSQL.Schema

37− ( -- * Postgres Types

33+ ( -- * Types

38 PGType (..)

34 PGType (..)

35+ , HasOid (..)

39 , NullityType (..)

36 , NullityType (..)

40− , RowType

41− , FromType

42− -- * Schema Types

43 , ColumnType

37 , ColumnType

44 , ColumnsType

38 , ColumnsType

39+ , RelationType

40+ , NilRelation

41+ , RelationsType

45 , TableType

42 , TableType

46− , SchemumType (..)

43+ -- * Grouping

47− , IndexType (..)

44+ , Grouping (..)

48− , FunctionType

45+ , GroupedBy

49− , OperatorType (..)

50− , ReturnsType (..)

51− , SchemaType

52− , SchemasType

53− , Public

54 -- * Constraints

46 -- * Constraints

55 , (:=>)

47 , (:=>)

56 , ColumnConstraint (..)

48 , ColumnConstraint (..)

57 , TableConstraint (..)

49 , TableConstraint (..)

58 , TableConstraints

50 , TableConstraints

51+ , NilTableConstraints

59 , Uniquely

52 , Uniquely

60− -- * Enumerated Labels

53+ -- * Aliases

61− , IsPGlabel (..)

54+ , (:::)

62− , PGlabel (..)

55+ , Alias (Alias)

63− -- * Data Definitions

56+ , renderAlias

57+ , renderAliases

58+ , Aliased (As)

59+ , renderAliasedAs

60+ , AliasesOf

61+ , Has

62+ , HasUnique

63+ , HasAll

64+ , IsLabel (..)

65+ , IsQualified (..)

66+ -- * Type Families

67+ , Join

64 , Create

68 , Create

65− , CreateIfNotExists

66− , CreateOrReplace

67 , Drop

69 , Drop

68− , DropSchemum

69− , DropIfExists

70− , DropSchemumIfExists

71 , Alter

70 , Alter

72− , AlterIfExists

73 , Rename

71 , Rename

74− , RenameIfExists

72+ , Elem

75− , ConstraintInvolves

73+ , In

76− , DropIfConstraintsInvolve

77− , IsNotElem

78− , AllUnique

79− -- * Type Classifications

80 , PGNum

74 , PGNum

81 , PGIntegral

75 , PGIntegral

82 , PGFloating

76 , PGFloating

83 , PGTypeOf

77 , PGTypeOf

84− , PGJsonType

78+ , SameTypes

85− , PGJsonKey

86 , SamePGType

79 , SamePGType

87 , AllNotNull

80 , AllNotNull

88 , NotAllNull

81 , NotAllNull

89− -- * Nullifications

90 , NullifyType

82 , NullifyType

91− , NullifyRow

83+ , NullifyRelation

92− , NullifyFrom

84+ , NullifyRelations

93− -- * Table Conversions

85+ , ColumnsToRelation

86+ , RelationToColumns

94 , TableToColumns

87 , TableToColumns

95− , ColumnsToRow

88+ , ConstraintInvolves

96− , TableToRow

89+ , DropIfConstraintsInvolve

90+ -- * Generics

91+ , SameField

92+ , SameFields

93+ , SameLabel

94+ , SameLabels

95+ , MapMaybes (..)

96+ , Nulls

97+ , IsPGlabel (..)

98+ , PGlabel (..)

99+ , renderLabel

100+ , renderLabels

101+ , LabelOf

102+ , LabelsOf

103+ , DatatypeLabels

104+ -- * Schema

105+ , SchemumType (..)

106+ , SchemaType

107+ , With

97 ) where

108 ) where

109

99−import Control.Category

110+import Control.DeepSeq

111+import Data.ByteString

100import Data.Kind

112import Data.Kind

101import Data.Monoid hiding (All)

113import Data.Monoid hiding (All)

114+import Data.String

115+import Data.Word

102import Data.Type.Bool

116import Data.Type.Bool

103−import Generics.SOP

117+import GHC.OverloadedLabels

104import GHC.TypeLits

118import GHC.TypeLits

105−import Prelude hiding (id, (.))

106

119

107−import Squeal.PostgreSQL.Alias

120+import qualified GHC.Generics as GHC

108−import Squeal.PostgreSQL.List

121+import qualified Generics.SOP as SOP

109−import Squeal.PostgreSQL.Render

122+import qualified Generics.SOP.Type.Metadata as Type

110

123

111−-- $setup

112−-- >>> import Squeal.PostgreSQL

124+import Squeal.PostgreSQL.Render

113

125

114-- | `PGType` is the promoted datakind of PostgreSQL types.

126-- | `PGType` is the promoted datakind of PostgreSQL types.

115--

127--

128+-- >>> import Squeal.PostgreSQL.Schema

116-- >>> :kind 'PGbool

129-- >>> :kind 'PGbool

117-- 'PGbool :: PGType

130-- 'PGbool :: PGType

118data PGType

131data PGType

@@ -123,7 +136,6 @@ data PGType

123 | PGnumeric -- ^ arbitrary precision numeric type

136 | PGnumeric -- ^ arbitrary precision numeric type

124 | PGfloat4 -- ^ single precision floating-point number (4 bytes)

137 | PGfloat4 -- ^ single precision floating-point number (4 bytes)

125 | PGfloat8 -- ^ double precision floating-point number (8 bytes)

138 | PGfloat8 -- ^ double precision floating-point number (8 bytes)

126− | PGmoney -- ^ currency amount

127 | PGchar Nat -- ^ fixed-length character string

139 | PGchar Nat -- ^ fixed-length character string

128 | PGvarchar Nat -- ^ variable-length character string

140 | PGvarchar Nat -- ^ variable-length character string

129 | PGtext -- ^ variable-length character string

141 | PGtext -- ^ variable-length character string

@@ -138,16 +150,40 @@ data PGType

138 | PGinet -- ^ IPv4 or IPv6 host address

150 | PGinet -- ^ IPv4 or IPv6 host address

139 | PGjson -- ^ textual JSON data

151 | PGjson -- ^ textual JSON data

140 | PGjsonb -- ^ binary JSON data, decomposed

152 | PGjsonb -- ^ binary JSON data, decomposed

141− | PGvararray NullityType -- ^ variable length array

153+ | PGvararray PGType -- ^ variable length array

142− | PGfixarray [Nat] NullityType -- ^ fixed length array

154+ | PGfixarray Nat PGType -- ^ fixed length array

143− | PGenum [Symbol] -- ^ enumerated (enum) types are data types that comprise a static, ordered set of values.

155+ | PGenum [Symbol]

144− | PGcomposite RowType -- ^ a composite type represents the structure of a row or record; it is essentially just a list of field names and their data types.

156+ | PGcomposite [(Symbol, PGType)]

145− | PGtsvector -- ^ A tsvector value is a sorted list of distinct lexemes, which are words that have been normalized to merge different variants of the same word.

146− | PGtsquery -- ^ A tsquery value stores lexemes that are to be searched for.

147− | PGoid -- Object identifiers (OIDs) are used internally by PostgreSQL as primary keys for various system tables.

148− | PGrange PGType -- ^ Range types are data types representing a range of values of some element type (called the range's subtype).

149 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types

157 | UnsafePGType Symbol -- ^ an escape hatch for unsupported PostgreSQL types

150

158

159+-- | The object identifier of a `PGType`.

160+--

161+-- >>> :set -XTypeApplications

162+-- >>> oid @'PGbool

163+-- 16

164+class HasOid (ty :: PGType) where oid :: Word32

165+instance HasOid 'PGbool where oid = 16

166+instance HasOid 'PGint2 where oid = 21

167+instance HasOid 'PGint4 where oid = 23

168+instance HasOid 'PGint8 where oid = 20

169+instance HasOid 'PGnumeric where oid = 1700

170+instance HasOid 'PGfloat4 where oid = 700

171+instance HasOid 'PGfloat8 where oid = 701

172+instance HasOid ('PGchar n) where oid = 18

173+instance HasOid ('PGvarchar n) where oid = 1043

174+instance HasOid 'PGtext where oid = 25

175+instance HasOid 'PGbytea where oid = 17

176+instance HasOid 'PGtimestamp where oid = 1114

177+instance HasOid 'PGtimestamptz where oid = 1184

178+instance HasOid 'PGdate where oid = 1082

179+instance HasOid 'PGtime where oid = 1083

180+instance HasOid 'PGtimetz where oid = 1266

181+instance HasOid 'PGinterval where oid = 1186

182+instance HasOid 'PGuuid where oid = 2950

183+instance HasOid 'PGinet where oid = 869

184+instance HasOid 'PGjson where oid = 114

185+instance HasOid 'PGjsonb where oid = 3802

186+

151-- | `NullityType` encodes the potential presence or definite absence of a

187-- | `NullityType` encodes the potential presence or definite absence of a

152-- @NULL@ allowing operations which are sensitive to such to be well typed.

188-- @NULL@ allowing operations which are sensitive to such to be well typed.

153--

189--

@@ -166,6 +202,14 @@ data NullityType

166type (:=>) constraint ty = '(constraint,ty)

202type (:=>) constraint ty = '(constraint,ty)

167infixr 7 :=>

203infixr 7 :=>

168

204

205+-- | The alias operator `:::` is like a promoted version of `As`,

206+-- a type level pair between

207+-- an alias and some type, like a column alias and either a `ColumnType` or

208+-- `NullityType` or a table alias and either a `TableType` or a `RelationType`

209+-- or a constraint alias and a `TableConstraint`.

210+type (:::) (alias :: Symbol) ty = '(alias,ty)

211+infixr 6 :::

212+

169-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.

213-- | `ColumnConstraint` encodes the availability of @DEFAULT@ for inserts and updates.

170-- A column can be assigned a default value.

214-- A column can be assigned a default value.

171-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also

215-- A data `Squeal.PostgreSQL.Manipulations.Manipulation` command can also

@@ -207,14 +251,11 @@ data TableConstraint

207 | PrimaryKey [Symbol]

251 | PrimaryKey [Symbol]

208 | ForeignKey [Symbol] Symbol [Symbol]

252 | ForeignKey [Symbol] Symbol [Symbol]

209

253

210−{- | A `TableConstraints` is a row of `TableConstraint`s.

254+-- | A `TableConstraints` is a row of `TableConstraint`s.

211−

212−>>> :{

213−type family UsersConstraints :: TableConstraints where

214− UsersConstraints = '[ "pk_users" ::: 'PrimaryKey '["id"] ]

215−:}

216−-}

217type TableConstraints = [(Symbol,TableConstraint)]

255type TableConstraints = [(Symbol,TableConstraint)]

256+-- | A monokinded empty `TableConstraints`.

257+type family NilTableConstraints :: TableConstraints where

258+ NilTableConstraints = '[]

218

259

219-- | A `ForeignKey` must reference columns that either are

260-- | A `ForeignKey` must reference columns that either are

220-- a `PrimaryKey` or form a `Unique` constraint.

261-- a `PrimaryKey` or form a `Unique` constraint.

@@ -238,65 +279,190 @@ type family Uniquely

238-- :}

279-- :}

239type TableType = (TableConstraints,ColumnsType)

280type TableType = (TableConstraints,ColumnsType)

240

281

241−{- | A `RowType` is a row of `NullityType`. They correspond to Haskell

282+-- | `RelationType` is a row of `NullityType`

242−record types by means of `Squeal.PostgreSQL.Binary.RowPG` and are used in many places.

283+--

243−

244−>>> :{

284+-- >>> :{

245−type family PersonRow :: RowType where

285+-- type family PersonRelation :: RelationType where

246− PersonRow =

286+-- PersonRelation =

247− '[ "name" ::: 'NotNull 'PGtext

287+-- '[ "name" ::: 'NotNull 'PGtext

248− , "age" ::: 'NotNull 'PGint4

288+-- , "age" ::: 'NotNull 'PGint4

249− , "dateOfBirth" ::: 'Null 'PGdate

289+-- , "dateOfBirth" ::: 'Null 'PGdate

250− ]

290+-- ]

251−:}

291+-- :}

252−-}

253−type RowType = [(Symbol,NullityType)]

292+type RelationType = [(Symbol,NullityType)]

293+-- | A monokinded empty `RelationType`.

294+type family NilRelation :: RelationType where NilRelation = '[]

254

295

255−{- | `FromType` is a row of `RowType`s. It can be thought of as

296+-- | `RelationsType` is a row of `RelationType`s, thought of as a product.

256−a product, or horizontal gluing and is used in `Squeal.PostgreSQL.Query.FromClause`s

297+type RelationsType = [(Symbol,RelationType)]

257−and `Squeal.PostgreSQL.Query.TableExpression`s.

298+

258−-}

259−type FromType = [(Symbol,RowType)]

260−

261−-- | `ColumnsToRow` removes column constraints.

299+-- | `ColumnsToRelation` removes column constraints.

262−type family ColumnsToRow (columns :: ColumnsType) :: RowType where

300+type family ColumnsToRelation (columns :: ColumnsType) :: RelationType where

263− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': column5 ::: _ :=> ty5 ': columns) =

301+ ColumnsToRelation '[] = '[]

264− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': ColumnsToRow columns

302+ ColumnsToRelation (column ::: constraint :=> ty ': columns) =

265− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': column4 ::: _ :=> ty4 ': columns) =

303+ column ::: ty ': ColumnsToRelation columns

266− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': ColumnsToRow columns

304+

267− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': column3 ::: _ :=> ty3 ': columns) =

305+-- | `RelationToColumns` adds `'NoDef` column constraints.

268− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': ColumnsToRow columns

306+type family RelationToColumns (relation :: RelationType) :: ColumnsType where

269− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': column2 ::: _ :=> ty2 ': columns) =

307+ RelationToColumns '[] = '[]

270− column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': ColumnsToRow columns

271− ColumnsToRow (column ::: _ :=> ty ': column1 ::: _ :=> ty1 ': columns) =

308+ RelationToColumns (column ::: ty ': columns) =

272− column ::: ty ': column1 ::: ty1 ': ColumnsToRow columns

309+ column ::: 'NoDef :=> ty ': RelationToColumns columns

273− ColumnsToRow (column ::: _ :=> ty ': columns) =

274− column ::: ty ': ColumnsToRow columns

275− ColumnsToRow '[] = '[]

276

310

277-- | `TableToColumns` removes table constraints.

311-- | `TableToColumns` removes table constraints.

278type family TableToColumns (table :: TableType) :: ColumnsType where

312type family TableToColumns (table :: TableType) :: ColumnsType where

279 TableToColumns (constraints :=> columns) = columns

313 TableToColumns (constraints :=> columns) = columns

280

314

281−-- | Convert a table to a row type.

315+-- | `Grouping` is an auxiliary namespace, created by

282−type family TableToRow (table :: TableType) :: RowType where

316+-- @GROUP BY@ clauses (`Squeal.PostgreSQL.Query.group`), and used

283− TableToRow tab = ColumnsToRow (TableToColumns tab)

317+-- for typesafe aggregation

318+data Grouping

319+ = Ungrouped -- ^ no aggregation permitted

320+ | Grouped [(Symbol,Symbol)] -- ^ aggregation required for any column which is not grouped

284

321

285−-- | Numeric Postgres types.

322+{- | A `GroupedBy` constraint indicates that a table qualified column is

286−type PGNum =

323+a member of the auxiliary namespace created by @GROUP BY@ clauses and thus,

324+may be called in an output `Squeal.PostgreSQL.Expression.Expression` without aggregating.

325+-}

326+class (KnownSymbol relation, KnownSymbol column)

327+ => GroupedBy relation column bys where

328+instance {-# OVERLAPPING #-} (KnownSymbol relation, KnownSymbol column)

329+ => GroupedBy relation column ('(table,column) ': bys)

330+instance {-# OVERLAPPABLE #-}

331+ ( KnownSymbol relation

332+ , KnownSymbol column

333+ , GroupedBy relation column bys

334+ ) => GroupedBy relation column (tabcol ': bys)

335+

336+-- | `Alias`es are proxies for a type level string or `Symbol`

337+-- and have an `IsLabel` instance so that with @-XOverloadedLabels@

338+--

339+-- >>> :set -XOverloadedLabels

340+-- >>> #foobar :: Alias "foobar"

341+-- Alias

342+data Alias (alias :: Symbol) = Alias

343+ deriving (Eq,GHC.Generic,Ord,Show,NFData)

344+instance alias1 ~ alias2 => IsLabel alias1 (Alias alias2) where

345+ fromLabel = Alias

346+instance aliases ~ '[alias] => IsLabel alias (SOP.NP Alias aliases) where

347+ fromLabel = fromLabel SOP.:* SOP.Nil

348+

349+-- | >>> renderAlias #jimbob

350+-- "\"jimbob\""

351+renderAlias :: KnownSymbol alias => Alias alias -> ByteString

352+renderAlias = doubleQuoted . fromString . symbolVal

353+

354+-- | >>> import Generics.SOP (NP(..))

355+-- >>> renderAliases (#jimbob :* #kandi :* Nil)

356+-- ["\"jimbob\"","\"kandi\""]

357+renderAliases

358+ :: SOP.All KnownSymbol aliases => SOP.NP Alias aliases -> [ByteString]

359+renderAliases = SOP.hcollapse

360+ . SOP.hcmap (SOP.Proxy @KnownSymbol) (SOP.K . renderAlias)

361+

362+-- | The `As` operator is used to name an expression. `As` is like a demoted

363+-- version of `:::`.

364+--

365+-- >>> Just "hello" `As` #hi :: Aliased Maybe ("hi" ::: String)

366+-- As (Just "hello") Alias

367+data Aliased expression aliased where

368+ As

369+ :: KnownSymbol alias

370+ => expression ty

371+ -> Alias alias

372+ -> Aliased expression (alias ::: ty)

373+deriving instance Show (expression ty)

374+ => Show (Aliased expression (alias ::: ty))

375+deriving instance Eq (expression ty)

376+ => Eq (Aliased expression (alias ::: ty))

377+deriving instance Ord (expression ty)

378+ => Ord (Aliased expression (alias ::: ty))

379+

380+-- | >>> let renderMaybe = fromString . maybe "Nothing" (const "Just")

381+-- >>> renderAliasedAs renderMaybe (Just (3::Int) `As` #an_int)

382+-- "Just AS \"an_int\""

383+renderAliasedAs

384+ :: (forall ty. expression ty -> ByteString)

385+ -> Aliased expression aliased

386+ -> ByteString

387+renderAliasedAs render (expression `As` alias) =

388+ render expression <> " AS " <> renderAlias alias

389+

390+-- | `AliasesOf` retains the AliasesOf in a row.

391+type family AliasesOf aliaseds where

392+ AliasesOf '[] = '[]

393+ AliasesOf (alias ::: ty ': tys) = alias ': AliasesOf tys

394+

395+-- | @HasUnique alias fields field@ is a constraint that proves that

396+-- @fields@ is a singleton of @alias ::: field@.

397+type HasUnique alias fields field = fields ~ '[alias ::: field]

398+

399+-- | @Has alias fields field@ is a constraint that proves that

400+-- @fields@ has a field of @alias ::: field@.

401+class KnownSymbol alias =>

402+ Has (alias :: Symbol) (fields :: [(Symbol,kind)]) (field :: kind)

403+ | alias fields -> field where

404+instance {-# OVERLAPPING #-} KnownSymbol alias

405+ => Has alias (alias ::: field ': fields) field

406+instance {-# OVERLAPPABLE #-} (KnownSymbol alias, Has alias fields field)

407+ => Has alias (field' ': fields) field

408+

409+class

410+ ( SOP.All KnownSymbol aliases

411+ ) => HasAll

412+ (aliases :: [Symbol])

413+ (fields :: [(Symbol,kind)])

414+ (subfields :: [(Symbol,kind)])

415+ | aliases fields -> subfields where

416+instance {-# OVERLAPPING #-} HasAll '[] fields '[]

417+instance {-# OVERLAPPABLE #-}

418+ (Has alias fields field, HasAll aliases fields subfields)

419+ => HasAll (alias ': aliases) fields (alias ::: field ': subfields)

420+

421+-- | Analagous to `IsLabel`, the constraint

422+-- `IsQualified` defines `!` for a column alias qualified

423+-- by a table alias.

424+class IsQualified table column expression where

425+ (!) :: Alias table -> Alias column -> expression

426+ infixl 9 !

427+instance IsQualified table column (Alias table, Alias column) where (!) = (,)

428+

429+-- | @Elem@ is a promoted `Data.List.elem`.

430+type family Elem x xs where

431+ Elem x '[] = 'False

432+ Elem x (x ': xs) = 'True

433+ Elem x (_ ': xs) = Elem x xs

434+

435+-- | @In x xs@ is a constraint that proves that @x@ is in @xs@.

436+type family In x xs :: Constraint where In x xs = Elem x xs ~ 'True

437+

438+-- | `PGNum` is a constraint on `PGType` whose

439+-- `Squeal.PostgreSQL.Expression.Expression`s have a `Num` constraint.

440+type PGNum ty =

287− '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]

441+ In ty '[ 'PGint2, 'PGint4, 'PGint8, 'PGnumeric, 'PGfloat4, 'PGfloat8]

288−

442+

289−-- | Floating Postgres types.

443+-- | `PGFloating` is a constraint on `PGType` whose

444+-- `Squeal.PostgreSQL.Expression.Expression`s

445+-- have `Fractional` and `Floating` constraints.

290−type PGFloating = '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]

446+type PGFloating ty = In ty '[ 'PGfloat4, 'PGfloat8, 'PGnumeric]

291−

447+

292−-- | Integral Postgres types.

448+-- | `PGIntegral` is a constraint on `PGType` whose

449+-- `Squeal.PostgreSQL.Expression.Expression`s

450+-- have `Squeal.PostgreSQL.Expression.div_` and

451+-- `Squeal.PostgreSQL.Expression.mod_` functions.

293−type PGIntegral = '[ 'PGint2, 'PGint4, 'PGint8]

452+type PGIntegral ty = In ty '[ 'PGint2, 'PGint4, 'PGint8]

294

453

295-- | `PGTypeOf` forgets about @NULL@ and any column constraints.

454-- | `PGTypeOf` forgets about @NULL@ and any column constraints.

296type family PGTypeOf (ty :: NullityType) :: PGType where

455type family PGTypeOf (ty :: NullityType) :: PGType where

297 PGTypeOf (nullity pg) = pg

456 PGTypeOf (nullity pg) = pg

298

457

299−-- | Equality constraint on the underlying `PGType` of two columns.

458+-- | `SameTypes` is a constraint that proves two `ColumnsType`s have the same

459+-- length and the same `ColumnType`s.

460+type family SameTypes (columns0 :: ColumnsType) (columns1 :: ColumnsType)

461+ :: Constraint where

462+ SameTypes '[] '[] = ()

463+ SameTypes (column0 ::: def0 :=> ty0 ': columns0) (column1 ::: def1 :=> ty1 ': columns1)

464+ = (ty0 ~ ty1, SameTypes columns0 columns1)

465+

300class SamePGType

466class SamePGType

301 (ty0 :: (Symbol,ColumnType)) (ty1 :: (Symbol,ColumnType)) where

467 (ty0 :: (Symbol,ColumnType)) (ty1 :: (Symbol,ColumnType)) where

302instance ty0 ~ ty1 => SamePGType

468instance ty0 ~ ty1 => SamePGType

@@ -305,63 +471,39 @@ instance ty0 ~ ty1 => SamePGType

305

471

306-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.

472-- | `AllNotNull` is a constraint that proves a `ColumnsType` has no @NULL@s.

307type family AllNotNull (columns :: ColumnsType) :: Constraint where

473type family AllNotNull (columns :: ColumnsType) :: Constraint where

308− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

309− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

310− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

311− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

312− AllNotNull (_ ::: _ :=> 'NotNull _ ': _ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

313− AllNotNull (_ ::: _ :=> 'NotNull _ ': columns) = AllNotNull columns

314 AllNotNull '[] = ()

474 AllNotNull '[] = ()

475+ AllNotNull (column ::: def :=> 'NotNull ty ': columns) = AllNotNull columns

315

476

316-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some

477-- | `NotAllNull` is a constraint that proves a `ColumnsType` has some

317-- @NOT NULL@.

478-- @NOT NULL@.

318type family NotAllNull (columns :: ColumnsType) :: Constraint where

479type family NotAllNull (columns :: ColumnsType) :: Constraint where

319− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

480+ NotAllNull (column ::: def :=> 'NotNull ty ': columns) = ()

320− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

321− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

322− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

323− NotAllNull (_ ::: _ :=> _ _ ': _ ::: _ :=> 'NotNull _ ': _) = ()

324− NotAllNull (_ ::: _ :=> 'NotNull _ ': _) = ()

325− NotAllNull (_ ::: _ :=> 'Null _ ': columns) = NotAllNull columns

481+ NotAllNull (column ::: def :=> 'Null ty ': columns) = NotAllNull columns

326−

482+

327−-- | `NullifyType` is an idempotent that nullifies a `NullityType`.

483+-- | `NullifyType` is an idempotent that nullifies a `ColumnType`.

328type family NullifyType (ty :: NullityType) :: NullityType where

484type family NullifyType (ty :: NullityType) :: NullityType where

329 NullifyType ('Null ty) = 'Null ty

485 NullifyType ('Null ty) = 'Null ty

330 NullifyType ('NotNull ty) = 'Null ty

486 NullifyType ('NotNull ty) = 'Null ty

331

487

332−-- | `NullifyRow` is an idempotent that nullifies a `RowType`.

488+-- | `NullifyRelation` is an idempotent that nullifies a `ColumnsType`.

333−type family NullifyRow (columns :: RowType) :: RowType where

489+type family NullifyRelation (columns :: RelationType) :: RelationType where

334− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': column5 ::: ty5 ': columns) =

490+ NullifyRelation '[] = '[]

335− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': column5 ::: NullifyType ty5 ': NullifyRow columns

491+ NullifyRelation (column ::: ty ': columns) =

336− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': column4 ::: ty4 ': columns) =

492+ column ::: NullifyType ty ': NullifyRelation columns

337− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': column4 ::: NullifyType ty4 ': NullifyRow columns

493+

338− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': column3 ::: ty3 ': columns) =

339− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': column3 ::: NullifyType ty3 ': NullifyRow columns

340− NullifyRow (column ::: ty ': column1 ::: ty1 ': column2 ::: ty2 ': columns) =

341− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': column2 ::: NullifyType ty2 ': NullifyRow columns

342− NullifyRow (column ::: ty ': column1 ::: ty1 ': columns) =

343− column ::: NullifyType ty ': column1 ::: NullifyType ty1 ': NullifyRow columns

344− NullifyRow (column ::: ty ': columns) =

345− column ::: NullifyType ty ': NullifyRow columns

346− NullifyRow '[] = '[]

347−

348−-- | `NullifyFrom` is an idempotent that nullifies a `FromType`

494+-- | `NullifyRelations` is an idempotent that nullifies a `RelationsType`

349-- used to nullify the left or right hand side of an outer join

495-- used to nullify the left or right hand side of an outer join

350-- in a `Squeal.PostgreSQL.Query.FromClause`.

496-- in a `Squeal.PostgreSQL.Query.FromClause`.

351−type family NullifyFrom (tables :: FromType) :: FromType where

497+type family NullifyRelations (tables :: RelationsType) :: RelationsType where

352− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': table5 ::: columns5 ': tables) =

498+ NullifyRelations '[] = '[]

353− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns5 ': table5 ::: NullifyRow columns4 ': NullifyFrom tables

499+ NullifyRelations (table ::: columns ': tables) =

354− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': table4 ::: columns4 ': tables) =

500+ table ::: NullifyRelation columns ': NullifyRelations tables

355− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': table4 ::: NullifyRow columns4 ': NullifyFrom tables

501+

356− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': table3 ::: columns3 ': tables) =

502+-- | `Join` is simply promoted `++` and is used in @JOIN@s in

357− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': table3 ::: NullifyRow columns3 ': NullifyFrom tables

503+-- `Squeal.PostgreSQL.Query.FromClause`s.

358− NullifyFrom (table ::: columns ': table1 ::: columns1 ': table2 ::: columns2 ': tables) =

504+type family Join xs ys where

359− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': table2 ::: NullifyRow columns2 ': NullifyFrom tables

505+ Join '[] ys = ys

360− NullifyFrom (table ::: columns ': table1 ::: columns1 ': tables) =

506+ Join (x ': xs) ys = x ': Join xs ys

361− table ::: NullifyRow columns ': table1 ::: NullifyRow columns1 ': NullifyFrom tables

362− NullifyFrom (table ::: columns ': tables) =

363− table ::: NullifyRow columns ': NullifyFrom tables

364− NullifyFrom '[] = '[]

365

507

366-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in

508-- | @Create alias x xs@ adds @alias ::: x@ to the end of @xs@ and is used in

367-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@

509-- `Squeal.PostgreSQL.Definition.createTable` statements and in @ALTER TABLE@

@@ -371,100 +513,91 @@ type family Create alias x xs where

371 Create alias x (alias ::: y ': xs) = TypeError

513 Create alias x (alias ::: y ': xs) = TypeError

372 ('Text "Create: alias "

514 ('Text "Create: alias "

373 ':<>: 'ShowType alias

515 ':<>: 'ShowType alias

374− ':<>: 'Text "already exists")

516+ ':<>: 'Text "already in use")

375 Create alias y (x ': xs) = x ': Create alias y xs

517 Create alias y (x ': xs) = x ': Create alias y xs

376

518

377−type family CreateIfNotExists alias x xs where

378− CreateIfNotExists alias x '[] = '[alias ::: x]

379− CreateIfNotExists alias x (alias ::: y ': xs) = alias ::: y ': xs

380− CreateIfNotExists alias y (x ': xs) = x ': CreateIfNotExists alias y xs

381−

382−type family CreateOrReplace alias x xs where

383− CreateOrReplace alias x '[] = '[alias ::: x]

384− CreateOrReplace alias x (alias ::: x ': xs) = alias ::: x ': xs

385− CreateOrReplace alias x (alias ::: y ': xs) = TypeError

386− ('Text "CreateOrReplace: expected type "

387− ':<>: 'ShowType x

388− ':<>: 'Text " but alias "

389− ':<>: 'ShowType alias

390− ':<>: 'Text " has type "

391− ':<>: 'ShowType y)

392− CreateOrReplace alias y (x ': xs) = x ': CreateOrReplace alias y xs

393−

394-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@

519-- | @Drop alias xs@ removes the type associated with @alias@ in @xs@

395-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements

520-- and is used in `Squeal.PostgreSQL.Definition.dropTable` statements

396-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.

521-- and in @ALTER TABLE@ `Squeal.PostgreSQL.Definition.dropColumn` statements.

397type family Drop alias xs where

522type family Drop alias xs where

398− Drop alias '[] = TypeError

399− ('Text "Drop: alias "

400− ':<>: 'ShowType alias

401− ':<>: 'Text " does not exist" )

402− Drop alias (alias ::: x ': xs) = xs

523+ Drop alias ((alias ::: x) ': xs) = xs

403 Drop alias (x ': xs) = x ': Drop alias xs

524 Drop alias (x ': xs) = x ': Drop alias xs

404

525

405−type family DropSchemum alias sch xs where

406− DropSchemum alias sch '[] = TypeError

407− ('Text "DropSchemum: alias "

408− ':<>: 'ShowType alias

409− ':<>: 'Text " does not exist" )

410− DropSchemum alias sch (alias ::: sch x ': xs) = xs

411− DropSchemum alias sch0 (alias ::: sch1 x ': xs) = TypeError

412− ('Text "DropSchemum: expected schemum "

413− ':<>: 'ShowType sch0

414− ':<>: 'Text " but alias "

415− ':<>: 'ShowType alias

416− ':<>: 'Text " has schemum "

417− ':<>: 'ShowType sch1)

418− DropSchemum alias sch (x ': xs) = x ': DropSchemum alias sch xs

419−

420−type family DropIfExists alias xs where

421− DropIfExists alias '[] = '[]

422− DropIfExists alias (alias ::: x ': xs) = xs

423− DropIfExists alias (x ': xs) = x ': DropIfExists alias xs

424−

425−type family DropSchemumIfExists alias sch xs where

426− DropSchemumIfExists alias sch '[] = '[]

427− DropSchemumIfExists alias sch (alias ::: sch x ': xs) = xs

428− DropSchemumIfExists alias sch0 (alias ::: sch1 x ': xs) = TypeError

429− ('Text "DropSchemumIfExists: expected schemum "

430− ':<>: 'ShowType sch1

431− ':<>: 'Text " but alias "

432− ':<>: 'ShowType alias

433− ':<>: 'Text " has schemum "

434− ':<>: 'ShowType sch0)

435− DropSchemumIfExists alias sch (x ': xs) = x ': DropSchemumIfExists alias sch xs

436−

437-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@

526-- | @Alter alias x xs@ replaces the type associated with an @alias@ in @xs@

438−-- with the type @x@ and is used in `Squeal.PostgreSQL.Definition.alterTable`

527+-- with the type `x` and is used in `Squeal.PostgreSQL.Definition.alterTable`

439-- and `Squeal.PostgreSQL.Definition.alterColumn`.

528-- and `Squeal.PostgreSQL.Definition.alterColumn`.

440type family Alter alias x xs where

529type family Alter alias x xs where

441− Alter alias x '[] = TypeError

442− ('Text "Alter: alias "

443− ':<>: 'ShowType alias

444− ':<>: 'Text " does not exist" )

445 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

530 Alter alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

446 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs

531 Alter alias x1 (x0 ': xs) = x0 ': Alter alias x1 xs

447

532

448−type family AlterIfExists alias x xs where

533+-- type family AddConstraint constraint ty where

449− AlterIfExists alias x '[] = '[]

534+-- AddConstraint constraint (constraints :=> ty)

450− AlterIfExists alias x1 (alias ::: x0 ': xs) = alias ::: x1 ': xs

535+-- = AsSet (constraint ': constraints) :=> ty

451− AlterIfExists alias x1 (x0 ': xs) = x0 ': AlterIfExists alias x1 xs

536+

537+-- type family DeleteFromList (e :: elem) (list :: [elem]) where

538+-- DeleteFromList elem '[] = '[]

539+-- DeleteFromList elem (x ': xs) =

540+-- If (Cmp elem x == 'EQ) xs (x ': DeleteFromList elem xs)

541+

542+-- type family DropConstraint constraint ty where

543+-- DropConstraint constraint (constraints :=> ty)

544+-- = (AsSet (DeleteFromList constraint constraints)) :=> ty

452

545

453-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@

546-- | @Rename alias0 alias1 xs@ replaces the alias @alias0@ by @alias1@ in @xs@

454-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and

547-- and is used in `Squeal.PostgreSQL.Definition.alterTableRename` and

455-- `Squeal.PostgreSQL.Definition.renameColumn`.

548-- `Squeal.PostgreSQL.Definition.renameColumn`.

456type family Rename alias0 alias1 xs where

549type family Rename alias0 alias1 xs where

457− Rename alias0 alias1 '[] = TypeError

458− ('Text "Rename: alias "

459− ':<>: 'ShowType alias0

460− ':<>: 'Text " does not exist" )

461 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs

550 Rename alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs

462 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs

551 Rename alias0 alias1 (x ': xs) = x ': Rename alias0 alias1 xs

463

552

464−type family RenameIfExists alias0 alias1 xs where

553+-- | A `SameField` constraint is an equality constraint on a

465− RenameIfExists alias x '[] = '[]

554+-- `Generics.SOP.Type.Metadata.FieldInfo` and the column alias in a `:::` pair.

466− RenameIfExists alias0 alias1 ((alias0 ::: x0) ': xs) = (alias1 ::: x0) ': xs

555+class SameField

467− RenameIfExists alias0 alias1 (x ': xs) = x ': RenameIfExists alias0 alias1 xs

556+ (fieldInfo :: Type.FieldInfo) (fieldty :: (Symbol,NullityType)) where

557+instance field ~ column => SameField ('Type.FieldInfo field) (column ::: ty)

558+

559+-- | A `SameFields` constraint proves that a

560+-- `Generics.SOP.Type.Metadata.DatatypeInfo` of a record type has the same

561+-- field names as the column AliasesOf of a `ColumnsType`.

562+type family SameFields

563+ (datatypeInfo :: Type.DatatypeInfo) (columns :: [(Symbol,ty)])

564+ :: Constraint where

565+ SameFields

566+ ('Type.ADT _module _datatype '[ 'Type.Record _constructor fields])

567+ columns

568+ = SOP.AllZip SameField fields columns

569+ SameFields

570+ ('Type.Newtype _module _datatype ('Type.Record _constructor fields))

571+ columns

572+ = SOP.AllZip SameField fields columns

573+

574+class SameLabel

575+ (constrInfo :: Type.ConstructorInfo) (label :: Symbol) where

576+instance name ~ label => SameLabel ('Type.Constructor name) label

577+

578+type family SameLabels

579+ (datatypeInfo :: Type.DatatypeInfo) (labels :: [Symbol])

580+ :: Constraint where

581+ SameLabels

582+ ('Type.ADT _module _datatype constructors) labels

583+ = SOP.AllZip SameLabel constructors labels

584+

585+class MapMaybes xs where

586+ type family Maybes (xs :: [Type]) = (mxs :: [Type]) | mxs -> xs

587+ maybes :: SOP.NP Maybe xs -> SOP.NP SOP.I (Maybes xs)

588+ unMaybes :: SOP.NP SOP.I (Maybes xs) -> SOP.NP Maybe xs

589+instance MapMaybes '[] where

590+ type Maybes '[] = '[]

591+ maybes SOP.Nil = SOP.Nil

592+ unMaybes SOP.Nil = SOP.Nil

593+instance MapMaybes xs => MapMaybes (x ': xs) where

594+ type Maybes (x ': xs) = Maybe x ': Maybes xs

595+ maybes (x SOP.:* xs) = SOP.I x SOP.:* maybes xs

596+ unMaybes (SOP.I mx SOP.:* xs) = mx SOP.:* unMaybes xs

597+

598+type family Nulls tys where

599+ Nulls '[] = '[]

600+ Nulls (field ::: ty ': tys) = field ::: 'Null ty ': Nulls tys

468

601

469-- | Check if a `TableConstraint` involves a column

602-- | Check if a `TableConstraint` involves a column

470type family ConstraintInvolves column constraint where

603type family ConstraintInvolves column constraint where

@@ -482,115 +615,41 @@ type family DropIfConstraintsInvolve column constraints where

482 (DropIfConstraintsInvolve column constraints)

615 (DropIfConstraintsInvolve column constraints)

483 (alias ::: constraint ': DropIfConstraintsInvolve column constraints)

616 (alias ::: constraint ': DropIfConstraintsInvolve column constraints)

484

617

485−-- | A `SchemumType` is a user-defined type, either a `Table`,

486−-- `View` or `Typedef`.

487data SchemumType

618data SchemumType

488 = Table TableType

619 = Table TableType

489− | View RowType

620+ | View RelationType

490 | Typedef PGType

621 | Typedef PGType

491− | Index IndexType

622+

492− | Function FunctionType

493− | Operator OperatorType

494− | UnsafeSchemum Symbol

495−

496−type FunctionType = ([NullityType], ReturnsType)

497−

498−data IndexType

499− = Btree

500− | Hash

501− | Gist

502− | Spgist

503− | Gin

504− | Brin

505−

506−data ReturnsType

507− = Returns NullityType

508− | ReturnsTable RowType

509−

510−data OperatorType

511− = BinaryOp NullityType NullityType NullityType

512− | LeftOp NullityType NullityType

513− | RightOp NullityType NullityType

514−

515−{- | The schema of a database consists of a list of aliased,

516−user-defined `SchemumType`s.

517−

518−>>> :{

519−type family Schema :: SchemaType where

520− Schema =

521− '[ "users" ::: 'Table (

522− '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>

523− '[ "id" ::: 'Def :=> 'NotNull 'PGint4

524− , "name" ::: 'NoDef :=> 'NotNull 'PGtext

525− ])

526− , "emails" ::: 'Table (

527− '[ "pk_emails" ::: 'PrimaryKey '["id"]

528− , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]

529− ] :=>

530− '[ "id" ::: 'Def :=> 'NotNull 'PGint4

531− , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4

532− , "email" ::: 'NoDef :=> 'Null 'PGtext

533− ])

534− ]

535−:}

536−-}

537type SchemaType = [(Symbol,SchemumType)]

623type SchemaType = [(Symbol,SchemumType)]

538

624

539−{- |

625+type family With

540−A database contains one or more named schemas, which in turn contain tables.

626+ (relations :: RelationsType)

541−The same object name can be used in different schemas without conflict;

627+ (schema :: SchemaType)

542−for example, both schema1 and myschema can contain tables named mytable.

628+ :: SchemaType where

543−Unlike databases, schemas are not rigidly separated:

629+ With '[] schema = schema

544−a user can access objects in any of the schemas in the database they are connected to,

630+ With (alias ::: rel ': rels) schema =

545−if they have privileges to do so.

631+ alias ::: 'View rel ': With rels schema

546

632

547−There are several reasons why one might want to use schemas:

633+class IsPGlabel (label :: Symbol) expr where label :: expr

634+instance label ~ label'

635+ => IsPGlabel label (PGlabel label') where label = PGlabel

636+data PGlabel (label :: Symbol) = PGlabel

548

637

549− * To allow many users to use one database without interfering with each other.

638+renderLabel :: KnownSymbol label => proxy label -> ByteString

550− * To organize database objects into logical groups to make them more manageable.

639+renderLabel (_ :: proxy label) =

551− * Third-party applications can be put into separate schemas

640+ "\'" <> fromString (symbolVal (SOP.Proxy @label)) <> "\'"

552− so they do not collide with the names of other objects.

553−-}

554−type SchemasType = [(Symbol,SchemaType)]

555

641

556−-- | A type family to use for a single schema database.

642+renderLabels

557−type family Public (schema :: SchemaType) :: SchemasType

643+ :: SOP.All KnownSymbol labels => SOP.NP PGlabel labels -> [ByteString]

558− where Public schema = '["public" ::: schema]

644+renderLabels = SOP.hcollapse

645+ . SOP.hcmap (SOP.Proxy @KnownSymbol) (SOP.K . renderLabel)

559

646

560−-- | `IsPGlabel` looks very much like the `IsLabel` class. Whereas

647+type family LabelOf (cons :: Type.ConstructorInfo) :: Symbol where

561−-- the overloaded label, `fromLabel` is used for column references,

648+ LabelOf ('Type.Constructor name) = name

562−-- `label`s are used for enum terms. A `label` is called with

649+

563−-- type application like `label @"beef"`.

650+type family LabelsOf (conss :: [Type.ConstructorInfo]) :: [Symbol] where

564−class IsPGlabel (label :: Symbol) expr where label :: expr

651+ LabelsOf '[] = '[]

565−instance label ~ label1

652+ LabelsOf (cons ': conss) = LabelOf cons ': LabelsOf conss

566− => IsPGlabel label (PGlabel label1) where label = PGlabel

653+

567−instance labels ~ '[label]

654+type family DatatypeLabels (info :: Type.DatatypeInfo) :: [Symbol] where

568− => IsPGlabel label (NP PGlabel labels) where label = PGlabel :* Nil

655+ DatatypeLabels ('Type.ADT _module _datatype constructors) = LabelsOf constructors

569−-- | A `PGlabel` unit type with an `IsPGlabel` instance

570−data PGlabel (label :: Symbol) = PGlabel

571−instance KnownSymbol label => RenderSQL (PGlabel label) where

572− renderSQL _ = "\'" <> renderSymbol @label <> "\'"

573−instance All KnownSymbol labels => RenderSQL (NP PGlabel labels) where

574− renderSQL

575− = commaSeparated

576− . hcollapse

577− . hcmap (Proxy @KnownSymbol) (K . renderSQL)

578−

579−-- | Is a type a valid JSON key?

580−type PGJsonKey = '[ 'PGint2, 'PGint4, 'PGtext ]

581−

582−-- | Is a type a valid JSON type?

583−type PGJsonType = '[ 'PGjson, 'PGjsonb ]

584−

585−-- | Utility class for `AllUnique` to provide nicer error messages.

586−class IsNotElem x isElem where

587−instance IsNotElem x 'False where

588−instance (TypeError ( 'Text "Cannot assign to "

589− ':<>: 'ShowType alias

590− ':<>: 'Text " more than once"))

591− => IsNotElem '(alias, a) 'True where

592−

593−-- | No elem of @xs@ appears more than once, in the context of assignment.

594−class AllUnique (xs :: [(Symbol, a)]) where

595−instance AllUnique '[] where

596−instance (IsNotElem x (Elem x xs), AllUnique xs) => AllUnique (x ': xs) where

squeal-postgresql/src/Squeal/PostgreSQL/Transaction.hs+78−105

@@ -1,7 +1,7 @@

1{-|

2Module: Squeal.PostgreSQL.Transaction

3Description: Squeal transaction control language

4−Copyright: (c) Eitan Chatav, 2019

4+Copyright: (c) Eitan Chatav, 2017

5Maintainer: eitan@morphism.tech

6Stability: experimental

@@ -9,125 +9,98 @@ Squeal transaction control language.

9-}

11{-# LANGUAGE

12− DataKinds

13− , FlexibleContexts

12+ FlexibleContexts

14 , LambdaCase

13 , LambdaCase

15 , OverloadedStrings

14 , OverloadedStrings

16− , TypeInType

17#-}

15#-}

19module Squeal.PostgreSQL.Transaction

17module Squeal.PostgreSQL.Transaction

20 ( -- * Transaction

18 ( -- * Transaction

21 transactionally

19 transactionally

22 , transactionally_

20 , transactionally_

23− , transactionallyRetry

24− , ephemerally

25− , ephemerally_

26 , begin

21 , begin

27 , commit

22 , commit

28 , rollback

23 , rollback

24+ , transactionallySchema

25+ , transactionallySchema_

29 -- * Transaction Mode

26 -- * Transaction Mode

30 , TransactionMode (..)

27 , TransactionMode (..)

31 , defaultMode

28 , defaultMode

32 , longRunningMode

29 , longRunningMode

33 , IsolationLevel (..)

30 , IsolationLevel (..)

31+ , renderIsolationLevel

34 , AccessMode (..)

32 , AccessMode (..)

33+ , renderAccessMode

35 , DeferrableMode (..)

34 , DeferrableMode (..)

35+ , renderDeferrableMode

36 ) where

38−import UnliftIO

38+import Control.Exception.Lifted

39+import Control.Monad.Base

40+import Control.Monad.Trans.Control

41+import Data.ByteString

42+import Data.Monoid

43+import Generics.SOP

44+

45+import qualified Database.PostgreSQL.LibPQ as LibPQ

40import Squeal.PostgreSQL.Manipulation

47import Squeal.PostgreSQL.Manipulation

41import Squeal.PostgreSQL.Render

48import Squeal.PostgreSQL.Render

42import Squeal.PostgreSQL.PQ

49import Squeal.PostgreSQL.PQ

50+import Squeal.PostgreSQL.Schema

44−{- | Run a computation `transactionally`;

52+-- | Run a schema invariant computation `transactionally`.

45−first `begin`,

46−then run the computation,

47−`onException` `rollback` and rethrow the exception,

48−otherwise `commit` and `return` the result.

49−-}

50transactionally

53transactionally

51− :: (MonadUnliftIO tx, MonadPQ schemas tx)

54+ :: (MonadBaseControl IO tx, MonadPQ schema tx)

52 => TransactionMode

55 => TransactionMode

53 -> tx x -- ^ run inside a transaction

56 -> tx x -- ^ run inside a transaction

54 -> tx x

57 -> tx x

55transactionally mode tx = mask $ \restore -> do

58transactionally mode tx = mask $ \restore -> do

56− manipulate_ $ begin mode

59+ _ <- begin mode

57− result <- restore tx `onException` (manipulate_ rollback)

60+ result <- restore tx `onException` rollback

58− manipulate_ commit

61+ _ <- commit

59 return result

62 return result

61−-- | Run a computation `transactionally_`, in `defaultMode`.

64+-- | Run a schema invariant computation `transactionally_` in `defaultMode`.

62transactionally_

65transactionally_

63− :: (MonadUnliftIO tx, MonadPQ schemas tx)

66+ :: (MonadBaseControl IO tx, MonadPQ schema tx)

64 => tx x -- ^ run inside a transaction

67 => tx x -- ^ run inside a transaction

65 -> tx x

68 -> tx x

66transactionally_ = transactionally defaultMode

69transactionally_ = transactionally defaultMode

68−{- |

69−`transactionallyRetry` a computation;

70−

71−* first `begin`,

72−* then `try` the computation,

73− - if it raises a serialization failure then `rollback` and restart the transaction,

74− - if it raises any other exception then `rollback` and rethrow the exception,

75− - otherwise `commit` and `return` the result.

76−-}

77−transactionallyRetry

78− :: (MonadUnliftIO tx, MonadPQ schemas tx)

79− => TransactionMode

80− -> tx x -- ^ run inside a transaction

81− -> tx x

82−transactionallyRetry mode tx = mask $ \restore ->

83− loop . try $ do

84− x <- restore tx

85− manipulate_ commit

86− return x

87− where

88− loop attempt = do

89− manipulate_ $ begin mode

90− attempt >>= \case

91− Left (PQException (PQState _ (Just "40001") _)) -> do

92− manipulate_ rollback

93− loop attempt

94− Left err -> do

95− manipulate_ rollback

96− throwIO err

97− Right x -> return x

98−

99−{- | Run a computation `ephemerally`;

100−Like `transactionally` but always `rollback`, useful in testing.

101−-}

102−ephemerally

103− :: (MonadUnliftIO tx, MonadPQ schemas tx)

104− => TransactionMode

105− -> tx x -- ^ run inside an ephemeral transaction

106− -> tx x

107−ephemerally mode tx = mask $ \restore -> do

108− manipulate_ $ begin mode

109− result <- restore tx `onException` (manipulate_ rollback)

110− manipulate_ rollback

111− return result

112−

113−{- | Run a computation `ephemerally` in `defaultMode`. -}

114−ephemerally_

115− :: (MonadUnliftIO tx, MonadPQ schemas tx)

116− => tx x -- ^ run inside an ephemeral transaction

117− -> tx x

118−ephemerally_ = ephemerally defaultMode

119−

120-- | @BEGIN@ a transaction.

71-- | @BEGIN@ a transaction.

121−begin :: TransactionMode -> Manipulation_ schemas () ()

72+begin :: MonadPQ schema tx => TransactionMode -> tx (K Result NilRelation)

122−begin mode = UnsafeManipulation $ "BEGIN" <+> renderSQL mode

73+begin mode = manipulate . UnsafeManipulation $

74+ "BEGIN" <+> renderTransactionMode mode <> ";"

123

124−-- | @COMMIT@ a transaction.

76+-- | @COMMIT@ a schema invariant transaction.

125−commit :: Manipulation_ schemas () ()

77+commit :: MonadPQ schema tx => tx (K Result NilRelation)

126−commit = UnsafeManipulation "COMMIT"

78+commit = manipulate $ UnsafeManipulation "COMMIT;"

127

128−-- | @ROLLBACK@ a transaction.

80+-- | @ROLLBACK@ a schema invariant transaction.

129−rollback :: Manipulation_ schemas () ()

81+rollback :: MonadPQ schema tx => tx (K Result NilRelation)

130−rollback = UnsafeManipulation "ROLLBACK"

82+rollback = manipulate $ UnsafeManipulation "ROLLBACK;"

83+

84+-- | Run a schema changing computation `transactionallySchema`.

85+transactionallySchema

86+ :: MonadBaseControl IO io

87+ => TransactionMode

88+ -> PQ schema0 schema1 io x

89+ -> PQ schema0 schema1 io x

90+transactionallySchema mode u = PQ $ \ conn -> mask $ \ restore -> do

91+ _ <- liftBase . LibPQ.exec (unK conn) $

92+ "BEGIN" <+> renderTransactionMode mode <> ";"

93+ x <- restore (unPQ u conn)

94+ `onException` (liftBase (LibPQ.exec (unK conn) "ROLLBACK"))

95+ _ <- liftBase $ LibPQ.exec (unK conn) "COMMIT"

96+ return x

97+

98+-- | Run a schema changing computation `transactionallySchema_` in `DefaultMode`.

99+transactionallySchema_

100+ :: MonadBaseControl IO io

101+ => PQ schema0 schema1 io x

102+ -> PQ schema0 schema1 io x

103+transactionallySchema_ = transactionallySchema defaultMode

131

104

132-- | The available transaction characteristics are the transaction `IsolationLevel`,

105-- | The available transaction characteristics are the transaction `IsolationLevel`,

133-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.

106-- the transaction `AccessMode` (`ReadWrite` or `ReadOnly`), and the `DeferrableMode`.

@@ -140,7 +113,7 @@ data TransactionMode = TransactionMode

140-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

113-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

141-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.

114-- `ReadWrite` `AccessMode` and `NotDeferrable` `DeferrableMode`.

142defaultMode :: TransactionMode

115defaultMode :: TransactionMode

143−defaultMode = TransactionMode ReadCommitted ReadWrite NotDeferrable

116+defaultMode = TransactionMode Serializable ReadWrite NotDeferrable

144

117

145-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

118-- | `TransactionMode` with a `Serializable` `IsolationLevel`,

146-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.

119-- `ReadOnly` `AccessMode` and `Deferrable` `DeferrableMode`.

@@ -149,12 +122,12 @@ longRunningMode :: TransactionMode

149longRunningMode = TransactionMode Serializable ReadOnly Deferrable

122longRunningMode = TransactionMode Serializable ReadOnly Deferrable

150

123

151-- | Render a `TransactionMode`.

124-- | Render a `TransactionMode`.

152−instance RenderSQL TransactionMode where

125+renderTransactionMode :: TransactionMode -> ByteString

153− renderSQL mode =

126+renderTransactionMode mode =

154− "ISOLATION LEVEL"

127+ "ISOLATION LEVEL"

155− <+> renderSQL (isolationLevel mode)

128+ <+> renderIsolationLevel (isolationLevel mode)

156− <+> renderSQL (accessMode mode)

129+ <+> renderAccessMode (accessMode mode)

157− <+> renderSQL (deferrableMode mode)

130+ <+> renderDeferrableMode (deferrableMode mode)

158

131

159-- | The SQL standard defines four levels of transaction isolation.

132-- | The SQL standard defines four levels of transaction isolation.

160-- The most strict is `Serializable`, which is defined by the standard in a paragraph

133-- The most strict is `Serializable`, which is defined by the standard in a paragraph

@@ -185,32 +158,32 @@ data IsolationLevel

185 = Serializable

158 = Serializable

186 -- ^ Dirty read is not possible.

159 -- ^ Dirty read is not possible.

187 -- Nonrepeatable read is not possible.

160 -- Nonrepeatable read is not possible.

188− -- Phantom read is not possible.

161+ -- Phantom read is not possible.

189 -- Serialization anomaly is not possible.

162 -- Serialization anomaly is not possible.

190 | RepeatableRead

163 | RepeatableRead

191 -- ^ Dirty read is not possible.

164 -- ^ Dirty read is not possible.

192 -- Nonrepeatable read is not possible.

165 -- Nonrepeatable read is not possible.

193− -- Phantom read is not possible.

166+ -- Phantom read is not possible.

194 -- Serialization anomaly is possible.

167 -- Serialization anomaly is possible.

195 | ReadCommitted

168 | ReadCommitted

196 -- ^ Dirty read is not possible.

169 -- ^ Dirty read is not possible.

197 -- Nonrepeatable read is possible.

170 -- Nonrepeatable read is possible.

198− -- Phantom read is possible.

171+ -- Phantom read is possible.

199 -- Serialization anomaly is possible.

172 -- Serialization anomaly is possible.

200 | ReadUncommitted

173 | ReadUncommitted

201 -- ^ Dirty read is not possible.

174 -- ^ Dirty read is not possible.

202 -- Nonrepeatable read is possible.

175 -- Nonrepeatable read is possible.

203− -- Phantom read is possible.

176+ -- Phantom read is possible.

204 -- Serialization anomaly is possible.

177 -- Serialization anomaly is possible.

205 deriving (Show, Eq)

178 deriving (Show, Eq)

206

179

207-- | Render an `IsolationLevel`.

180-- | Render an `IsolationLevel`.

208−instance RenderSQL IsolationLevel where

181+renderIsolationLevel :: IsolationLevel -> ByteString

209− renderSQL = \case

182+renderIsolationLevel = \case

210− Serializable -> "SERIALIZABLE"

183+ Serializable -> "SERIALIZABLE"

211− ReadCommitted -> "READ COMMITTED"

184+ ReadCommitted -> "READ COMMITTED"

212− ReadUncommitted -> "READ UNCOMMITTED"

185+ ReadUncommitted -> "READ UNCOMMITTED"

213− RepeatableRead -> "REPEATABLE READ"

186+ RepeatableRead -> "REPEATABLE READ"

214

187

215-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.

188-- | The transaction access mode determines whether the transaction is `ReadWrite` or `ReadOnly`.

216-- `ReadWrite` is the default. When a transaction is `ReadOnly`,

189-- `ReadWrite` is the default. When a transaction is `ReadOnly`,

@@ -227,10 +200,10 @@ data AccessMode

227 deriving (Show, Eq)

200 deriving (Show, Eq)

228

201

229-- | Render an `AccessMode`.

202-- | Render an `AccessMode`.

230−instance RenderSQL AccessMode where

203+renderAccessMode :: AccessMode -> ByteString

231− renderSQL = \case

204+renderAccessMode = \case

232− ReadWrite -> "READ WRITE"

205+ ReadWrite -> "READ WRITE"

233− ReadOnly -> "READ ONLY"

206+ ReadOnly -> "READ ONLY"

234

207

235-- | The `Deferrable` transaction property has no effect

208-- | The `Deferrable` transaction property has no effect

236-- unless the transaction is also `Serializable` and `ReadOnly`.

209-- unless the transaction is also `Serializable` and `ReadOnly`.

@@ -246,7 +219,7 @@ data DeferrableMode

246 deriving (Show, Eq)

219 deriving (Show, Eq)

247

220

248-- | Render a `DeferrableMode`.

221-- | Render a `DeferrableMode`.

249−instance RenderSQL DeferrableMode where

222+renderDeferrableMode :: DeferrableMode -> ByteString

250− renderSQL = \case

223+renderDeferrableMode = \case

251− Deferrable -> "DEFERRABLE"

224+ Deferrable -> "DEFERRABLE"

252− NotDeferrable -> "NOT DEFERRABLE"

225+ NotDeferrable -> "NOT DEFERRABLE"

squeal-postgresql/test/Doc.hsdeleted−6

@@ -1,6 +0,0 @@

1−module Main (main) where

2−

3−import Test.DocTest

4−

5−main :: IO ()

6−main = doctest [ "-isrc", "src" ]

squeal-postgresql/test/DocTest.hsnew file+18

@@ -0,0 +1,18 @@

1+module Main (main) where

3+import Test.DocTest

5+main :: IO ()

6+main = doctest

7+ [ "-isrc"

8+ , "src/Squeal/PostgreSQL.hs"

9+ , "src/Squeal/PostgreSQL/Binary.hs"

10+ , "src/Squeal/PostgreSQL/Definition.hs"

11+ , "src/Squeal/PostgreSQL/Manipulation.hs"

12+ , "src/Squeal/PostgreSQL/Query.hs"

13+ , "src/Squeal/PostgreSQL/Expression.hs"

14+ , "src/Squeal/PostgreSQL/PQ.hs"

15+ , "src/Squeal/PostgreSQL/Migration.hs"

16+ , "src/Squeal/PostgreSQL/Transaction.hs"

17+ , "src/Squeal/PostgreSQL/Pool.hs"

18+ ]

squeal-postgresql/test/Property.hsdeleted−166

@@ -1,166 +0,0 @@

1−{-# LANGUAGE

2− DataKinds

3− , GADTs

4− , LambdaCase

5− , OverloadedLabels

6− , OverloadedStrings

7− , TypeApplications

8− , TypeOperators

9−#-}

10−

11−module Main (main) where

12−

13−import Control.Monad.Trans

14−import Data.ByteString (ByteString)

15−import Data.ByteString.Char8 (unpack)

16−import Data.Scientific (fromFloatDigits)

17−import Data.Fixed (Fixed(MkFixed), Micro, Pico)

18−import Data.String (IsString(fromString))

19−import Data.Time

20−import Squeal.PostgreSQL hiding (check, defaultMain, Group)

21−import Hedgehog hiding (Range)

22−import qualified Hedgehog.Gen as Gen

23−import qualified Hedgehog.Main as Main

24−import qualified Hedgehog.Range as Range

25−

26−main :: IO ()

27−main = Main.defaultMain [checkSequential roundtrips]

28−

29−roundtrips :: Group

30−roundtrips = Group "roundtrips"

31− [ roundtrip int2 genInt16

32− , roundtrip int4 genInt32

33− , roundtrip int8 genInt64

34− , roundtrip bool Gen.bool

35− , roundtrip numeric genScientific

36− , roundtrip float4 genFloat

37− , roundtrip float8 genDouble

38− , roundtripOn normalizeTimeOfDay time genTimeOfDay

39− -- , roundtrip timetz genTimeWithZone normalizeTimeWithZone

40− , roundtripOn normalizeLocalTime timestamp genLocalTime

41− , roundtrip timestamptz genUTCTime

42− , roundtrip date genDay

43− , roundtrip interval genDiffTime

44− , roundtripOn normalizeIntRange int4range (genRange genInt32)

45− , roundtripOn normalizeIntRange int8range (genRange genInt64)

46− , roundtrip numrange (genRange genScientific)

47− , roundtripOn (fmap normalizeLocalTime) tsrange (genRange genLocalTime)

48− , roundtrip tstzrange (genRange genUTCTime)

49− , roundtripOn normalizeIntRange daterange (genRange genDay)

50− ]

51− where

52− genInt16 = Gen.int16 Range.exponentialBounded

53− genInt32 = Gen.int32 Range.exponentialBounded

54− genInt64 = Gen.int64 Range.exponentialBounded

55− genScientific = fromFloatDigits <$> genFloat

56− genPosFloat = Gen.float

57− (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)

58− genFloat = Gen.prune $ Gen.choice

59− [ genPosFloat

60− , negate <$> genPosFloat

61− , Gen.element [0,1/0] ]

62− genPosDouble = Gen.double

63− (Range.exponentialFloatFrom 1 minPosFloat maxPosFloat)

64− genDouble = Gen.prune $ Gen.choice

65− [ genPosDouble

66− , negate <$> genPosDouble

67− , Gen.element [0,1/0] ]

68− genRange gen = do

69− lb <- gen

70− ub <- Gen.filter (lb <) gen

71− Gen.element

72− [ Empty, singleton lb, whole

73− , lb <=..<= ub , lb <=..< ub, lb <..<= ub, lb <..< ub

74− , atLeast lb, moreThan lb, atMost ub, lessThan ub ]

75− genDay = do

76− y <- toInteger <$> Gen.int (Range.constant 2000 2019)

77− m <- Gen.int (Range.constant 1 12)

78− d <- Gen.int (Range.constant 1 28)

79− return $ fromGregorian y m d

80− genDiffTime = secondsToDiffTime . toInteger <$>

81− Gen.int (Range.constant 0 86401)

82− genUTCTime = UTCTime <$> genDay <*> genDiffTime

83− genTimeOfDay = do

84− h <- Gen.int (Range.constant 0 23)

85− m <- Gen.int (Range.constant 0 59)

86− s <- MkFixed . toInteger <$> Gen.int (Range.constant 0 59)

87− return $ TimeOfDay h m s

88− genLocalTime = LocalTime <$> genDay <*> genTimeOfDay

89− -- genTimeZone = Gen.element $ map (read @TimeZone)

90− -- [ "UTC", "UT", "GMT", "EST", "EDT", "CST"

91− -- , "CDT", "MST", "MDT", "PST", "PDT" ]

92− -- genTimeWithZone = (,) <$> genTimeOfDay <*> genTimeZone

93−

94−roundtrip

95− :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)

96− => TypeExpression schemas ('NotNull ty)

97− -> Gen x

98− -> (PropertyName, Property)

99−roundtrip = roundtripOn id

100−

101−roundtripOn

102− :: (OidOf ty, ToParam x ty, FromValue ty x, Show x, Eq x)

103− => (x -> x)

104− -> TypeExpression schemas ('NotNull ty)

105− -> Gen x

106− -> (PropertyName, Property)

107−roundtripOn norm ty gen = propertyWithName $ do

108− x <- forAll gen

109− Just (Only y) <- lift . withConnection connectionString $

110− firstRow =<< runQueryParams

111− (values_ (parameter @1 ty `as` #fromOnly)) (Only x)

112− norm x === y

113− where

114− propertyWithName prop =

115− (fromString (unpack (renderSQL ty)), property prop)

116−

117−maxPosFloat :: RealFloat a => a

118−maxPosFloat = x

119− where

120− n = floatDigits x

121− b = floatRadix x

122− (_, u) = floatRange x

123− x = encodeFloat (b^n - 1) (u - n)

124−

125−minPosFloat :: RealFloat a => a

126−minPosFloat = x

127− where

128− n = floatDigits x

129− b = floatRadix x

130− (l, _) = floatRange x

131− x = encodeFloat (b^n - 1) (l - n - 1)

132−

133−connectionString :: ByteString

134−connectionString = "host=localhost port=5432 dbname=exampledb"

135−

136−normalizeIntRange :: (Enum int, Ord int) => Range int -> Range int

137−normalizeIntRange = \case

138− Empty -> Empty

139− NonEmpty l u ->

140− let

141− l' = normalizeL l

142− u' = normalizeU u

143− in if emptyNormalized l' u' then Empty else NonEmpty l' u'

144− where

145− normalizeL = \case

146− Open l -> Closed (succ l)

147− normalized -> normalized

148− normalizeU = \case

149− Closed u -> Open (succ u)

150− normalized -> normalized

151− emptyNormalized (Closed l) (Open u) = l >= u

152− emptyNormalized _ _ = False

153−

154−normalizeTimeOfDay :: TimeOfDay -> TimeOfDay

155−normalizeTimeOfDay (TimeOfDay h m s) = TimeOfDay h m

156− . fromRational @Pico

157− . toRational @Micro

158− . fromRational @Micro

159− . toRational @Pico

160− $ s

161−

162−normalizeLocalTime :: LocalTime -> LocalTime

163−normalizeLocalTime (LocalTime d t) = LocalTime d (normalizeTimeOfDay t)

164−

165−-- normalizeTimeWithZone :: (TimeOfDay, TimeZone) -> (TimeOfDay, TimeZone)

166−-- normalizeTimeWithZone (t, z) = (normalizeTimeOfDay t, z)

squeal-postgresql/test/Spec.hsdeleted−136

@@ -1,136 +0,0 @@

1−{-# LANGUAGE

2− DataKinds

3− , DeriveAnyClass

4− , DeriveGeneric

5− , DerivingStrategies

6− , DuplicateRecordFields

7− , FlexibleContexts

8− , OverloadedLabels

9− , OverloadedLists

10− , OverloadedStrings

11− , TypeApplications

12− , TypeFamilies

13− , TypeInType

14− , TypeOperators

15−#-}

16−

17−module Main (main) where

18−

19−import Control.Concurrent.Async (replicateConcurrently)

20−import Data.ByteString (ByteString)

21−import Data.Int (Int32)

22−import Data.Text (Text)

23−import Test.Hspec

24−

25−import qualified Generics.SOP as SOP

26−import qualified GHC.Generics as GHC

27−

28−import Squeal.PostgreSQL

29−

30−main :: IO ()

31−main = hspec spec

32−

33−type Schemas = Public

34− '[ "users" ::: 'Table (

35− '[ "pk_users" ::: 'PrimaryKey '["id"]

36− , "unique_names" ::: 'Unique '["name"]

37− ] :=>

38− '[ "id" ::: 'Def :=> 'NotNull 'PGint4

39− , "name" ::: 'NoDef :=> 'NotNull 'PGtext ] ) ]

40−

41−data User = User

42− { userName :: Text

43− } deriving stock (Eq, Show, GHC.Generic)

44− deriving anyclass (SOP.Generic, SOP.HasDatatypeInfo)

45−

46−insertUser :: Manipulation_ Schemas User ()

47−insertUser = insertInto_ #users

48− (Values_ (Default `as` #id :* Set (param @1) `as` #name))

49−

50−setup :: Definition (Public '[]) Schemas

51−setup =

52− createTable #users

53− ( serial `as` #id :*

54− notNullable text `as` #name )

55− ( primaryKey #id `as` #pk_users :*

56− unique #name `as` #unique_names )

57−

58−teardown :: Definition Schemas (Public '[])

59−teardown = dropTable #users

60−

61−silence :: MonadPQ schemas pq => pq ()

62−silence = manipulate_ $

63− UnsafeManipulation "SET client_min_messages TO WARNING;"

64−

65−setupDB :: IO ()

66−setupDB = withConnection connectionString $

67− silence & pqThen (define setup)

68−

69−dropDB :: IO ()

70−dropDB = withConnection connectionString $

71− silence & pqThen (define teardown)

72−

73−connectionString :: ByteString

74−connectionString = "host=localhost port=5432 dbname=exampledb"

75−

76−spec :: Spec

77−spec = before_ setupDB . after_ dropDB $ do

78−

79− describe "Exceptions" $ do

80−

81− let

82− testUser = User "TestUser"

83− newUser = manipulateParams_ insertUser

84− insertUserTwice = newUser testUser >> newUser testUser

85− err23505 = PQException $ PQState FatalError (Just "23505")

86− (Just "ERROR: duplicate key value violates unique constraint \"unique_names\"\nDETAIL: Key (name)=(TestUser) already exists.\n")

87−

88− it "should be thrown for constraint violation" $

89− withConnection connectionString insertUserTwice

90− `shouldThrow` (== err23505)

91−

92− it "should be rethrown for constraint violation in a transaction" $

93− withConnection connectionString (transactionally_ insertUserTwice)

94− `shouldThrow` (== err23505)

95−

96− describe "Pools" $

97−

98− it "should manage concurrent transactions" $ do

99− pool <- createConnectionPool

100− "host=localhost port=5432 dbname=exampledb" 1 0.5 10

101− let

102− query :: Query_ (Public '[]) () (Only Char)

103− query = values_ (literal 'a' `as` #fromOnly)

104− session = usingConnectionPool pool . transactionally_ $ do

105− result <- runQuery query

106− Just (Only chr) <- firstRow result

107− return chr

108− chrs <- replicateConcurrently 10 session

109− chrs `shouldSatisfy` all (== 'a')

110−

111− describe "Ranges" $

112−

113− it "should correctly decode ranges" $ do

114−

115− rangesOut <- withConnection connectionString $ do

116− let

117− query :: Query_ (Public '[]) () (Only (Range Int32))

118− query = values

119− ( range int4range (atLeast 3) `as` #fromOnly )

120− [ range int4range (3 <=..< 5) `as` #fromOnly

121− , range int4range Empty `as` #fromOnly

122− , range int4range whole `as` #fromOnly ]

123− getRows =<< runQuery query

124− (fromOnly <$> rangesOut :: [Range Int32]) `shouldBe`

125− [ atLeast 3, 3 <=..< 5, Empty, whole ]

126−

127− describe "Parameters" $ do

128−

129− it "should run queries that don't reference all their parameters" $ do

130−

131− out <- withConnection connectionString $ do

132− let

133− query :: Query_ (Public '[]) (Char,Int32) (Only Int32)

134− query = values_ (param @2 `as` #fromOnly)

135− firstRow =<< runQueryParams query ('a', 3 :: Int32)

136− (fromOnly <$> out :: Maybe Int32) `shouldBe` Just 3

squeal-presentation-raveline.mddeleted−794

@@ -1,794 +0,0 @@

1−# Squeal

2−

3−_A bridge between SQL and Haskell_

4−

5−by [@Raveline](https://github.com/raveline)

6−

7−---

8−

9−# Rationale

10−

11−Using `postgresql-simple` you have a typical "Trial, error, despair" workflow:

12−

13−- Write query manually or semi-automatically

14−

15−- Write haskell code using the query

16−

17−- Pray that the query syntax is correct

18−

19−- Pray that it returns what you want

20−

21−- Realize the inefficiency of prayer when it comes to SQL

22−

23−- Iterate till it works

24−

25−---

26−

27−![Can't take this anymore](http://gif.eraveline.eu/static/img/0x16e.gif)

28−

29−---

30−

31−# Use your best friend: GHC

32−

33−Squeal provides several eDSL to make your SQL typesafe:

34−

35−- Type level eDSL to express schema;

36−

37−- Value level eDSL to manipulate schema (plus migration, yeehaw !);

38−

39−- Type level eDSL to express queries;

40−

41−- Value level eDSL to perform queries

42−

43−However, it's not an ORM. There's no caching, lazy loading - you retain control over your memory. Also, joins - and mostly aggregation after joins - have to be handled manually.

44−

45−---

46−

47−# Part I. Schema & migration

48−

49−---

50−

51−# The Schema

52−

53−- The schema will be used to validate _everything_: migration, queries, etc.

54−

55−- A schema is mostly a collection of tables.

56−

57−- In this presentation, we will create a very basic database modeling a parliament. We will store _members of parliament_ and _parliamentary groups_.

58−

59−- A simple Schema to represent a Parliament could be:

60−

61−```haskell

62−type Schema = '[ "mp" ::: 'Table MemberOfParliament

63− , "groupp" ::: 'Table ParliamentGroup ]

64−```

65−

66−---

67−

68−> _note_ We need the `DataKinds` extension to be able to express heterogenous lists containing

69−> specific types like this one.

70−

71−> You can perfectly call your table "group" and not "groupp" even though it is a

72−> keyword in SQL - Squeal queries will be properly escaped.

73−

74−---

75−

76−# A small example

77−

78−```haskell

79−type ParliamentaryGroup =

80− '[ "pk_groupp" ::: 'PrimaryKey '["groupp_id"]]

81− :=>

82− '[ "groupp_id" ::: 'NoDef :=> 'NotNull 'PGuuid

83− , "name" ::: 'NoDef :=> 'NotNull 'PGtext

84− ]

85−```

86−

87−- That's a whole simple table defined in one go.

88−

89−- `:::` lets us define a column or a constraint.

90−

91−- `:=>` associates the constraints to the column.

92−

93−- Let's split constraints and column to study the syntax a bit more.

94−

95−---

96−

97−> _note_ We are using `:::` and `:=>` to quickly express associations when writing

98−> our schema. We need the `TypeOperators` extension.]

99−

100−---

101−

102−![What does this means ?!](http://gif.eraveline.eu/static/img/0x27e.gif)

103−

104−---

105−

106−# Defining a table

107−

108−```haskell

109−type MemberOfParliament =

110− '[ "pk_mp" ::: 'PrimaryKey '["mp_id"]

111− , "fk_mp_groupp" ::: 'ForeignKey '["mp_group"] "groupp" '["groupp_id"]

112− ] :=> MpCols

113−```

114−

115−- A table is a collection of constraints associated to a collection of columns.

116−

117−- We defined a table named "mp".

118−

119−- It has a constraint named "pk_mp", defining its primary key on column "mp_id".

120−

121−- It has a constraint named "fk_mp_groupp" defining a foreign key on column "mg_group", connected to the column "groupp_id" of table "groupp".

122−

123−- These constraints will be associated to the columns defined in `MpCols`.

124−

125−---

126−

127−# Defining columns

128−

129−```haskell

130−type MpCols =

131− '[ "mp_id" ::: 'NoDef :=> 'NotNull 'PGuuid

132− , "first_name" ::: 'NoDef :=> 'NotNull 'PGtext

133− , "last_name" ::: 'NoDef :=> 'NotNull 'PGtext

134− ]

135−```

136−

137−- A listing of column associate, for each element:

138−

139− * a name;

140−

141− * the mention of an eventual default value;

142−

143− * the nullability;

144−

145− * the type (obviously).

146−

147−---

148−

149−> _note_ GHC is already helping. If I named the "mp_id" column differently,

150−> GHC would yell because I promised a primary key constraint on a column named `mp_id`, so there must be one.]

151−

152−---

153−

154−# Implementating the schema

155−

156−- We will carry this schema type pretty much everywhere.

157−

158−- But before we play with this schema, we need to implement it.

159−

160−---

161−

162−```haskell

163−setup :: Definition '[] Schema

164−setup =

165− createTable #groupp

166− ( notNullable uuid `as` #groupp_id

167− :* notNullable text `as` #name)

168− ( primaryKey #groupp_id `as` #pk_groupp )

169− >>> createTable #mp

170− ( notNullable uuid `as` #mp_id

171− :* notNullable text `as` #first_name

172− :* notNullable text `as` #last_name

173− :* notNullable text `as` #mp_group)

174− ( primaryKey #mp_id `as` #pk_mp

175− :* foreignKey #mp_group #groupp #groupp_id

176− OnDeleteCascade OnUpdateCascade

177− `as` #fk_mp_groupp)

178−```

179−

180−---

181−

182−# Damn, that's verbose

183−

184−- Yes. But you need verbosity to get type safety.

185−

186−- On the plus side, it's fairly straightforward.

187−

188−- You use `:*` to compose the element of the heterogenous list of columns.

189−

190−- You use `>>>` to compose table creation.

191−

192−> _note_ The compiler will catch any mistype between Schema and

193−> definition; wrong nullability, wrong type, wrong name, etc.

194−

195−---

196−

197−> _note_ You'll also need `OverloadedLabels`, for naming stuff.

198−> This is mostly to avoid having to write manual proxies all

199−> the time and for convenience.

200−

201−---

202−

203−# Setting up the schema

204−

205−- Squeal comes with a very good migration manager, handling _upgrades_ AND

206−_downgrades_.

207−

208−- A migration is a simple type:

209−

210−```haskell

211−Migration io schema0 schema1

212−```

213−

214−- The first parameter is a BaseMonad (typically, IO).

215−

216−- The second parameter is "the current schema of your DB".

217−

218−- The last one is "what you will migrate to".

219−

220−- The `Definition` type used to define upgrade and downgrade functions use the

221− same logic (from one schema to the other).

222−

223−---

224−

225−# Defining our first migration

226−

227−- We have the setup bit, we need the teardown:

228−

229−```haskell

230−tearDown :: Definition Schema '[]

231−tearDown = dropTable #mp >>> dropTable #groupp

232−```

233−

234−> _note_ GHC will also detect the _proper_ order of what you typed in

235−> downgrade and upgrade should there be any conflict (with foreign keys).

236−

237−```haskell

238−initDB :: Migration IO '[] Schema

239−initDB =

240− Migration { name = "Schema creation"

241− , up = void $ define setup

242− , down = void $ define tearDown }

243−```

244−

245−---

246−

247−# Simple migrator example

248−

249−```haskell

250−main :: IO ()

251−main = do

252− printSQL setup

253− void $ withConnection connectionString $

254− migrateUp $ single initDB

255−```

256−

257−- We print the migration query; you can do this for all queries generated through Squeal.

258−

259−- We use `migrateUp` to perform the migration.

260−

261−- You can run several migration at the same time, to run only one use `single`.

262−

263−---

264−

265−![That was easy](http://gif.eraveline.eu/static/img/0x47f.gif)

266−

267−---

268−

269−# Part II. Insertions

270−

271−---

272−

273−# Manipulations & Queries

274−

275−Besides the specific case of migration, you will mostly perform:

276−

277−- `Manipulation` : inserting, updating and deleting data.

278−

279−- `Query` : fetching data.

280−

281−- Both types are parametric over the same things:

282−

283− * A schema

284−

285− * Input parameters

286−

287− * Output

288−

289−- Simplified, they look like this:

290−

291−```haskell

292−Manipulation schema params columns

293−

294−Query schema params columns

295−```

296−

297−

298−---

299−

300−# Our Haskell model

301−

302−```haskell

303−type Parliament = [Group]

304−

305−data Group =

306− Group { name :: Text

307− , members :: [MemberOfParliament] }

308−

309−data MemberOfParliament =

310− MemberOfParliament { firstName :: Text

311− , lastName :: Text }

312−```

313−

314−> _note_ We didn't use anything from Squeal.

315−> The model can be entirely separated from the persistence layer.

316−

317−---

318−

319−# Inserting a Parliamentary Group

320−

321−- A group is very simple: it's a uuid and a name. Let's define our params:

322−

323−```haskell

324−type GroupInsertionParams = '[ 'NotNull 'PGuuid

325− , 'NotNull 'PGtext ]

326−```

327−

328−- Params are not named, but they are indexed. You just need nullability and type.

329−

330−---

331−

332−```haskell

333−groupInsertion :: Manipulation Schema GroupInsertionParams '[]

334−groupInsertion =

335− insertRow_ #groupp ( Set (param @1) `as` #groupp_id

336− :* Set (param @2) `as` #name )

337−```

338−

339−---

340−

341−- `TypeApplication` lets us use the index of parameters (counting from 1).

342−

343−- Once again: all this is checked by the compiler. Wrong name, wrong type... you'll get a compile error.

344−

345−- `insertRow_` is a simplified version of `insertRow`. `insertRow` lets you express a `RETURNING` clause and the expected behaviour in case of conflict.

346−

347−---

348−

349−_Inserting a Member of Parliament_

350−# Doing an INSERT INTO ... SELECT

351−

352−- We could create a naive query that takes MP uuid, first name, last name and group uuid...

353−

354−---

355−

356−- But that's boring. So let's use the `INSERT INTO ... SELECT`.

357−

358−---

359−

360−- We will build a query that will return as constants our MP's uuid, first name and last name...

361−

362−---

363−

364−- ... and fetch the uuid of a group given the name of the group.

365−

366−---

367−

368−- There's a `insertQuery` utility function for that. All we have to do is write the `select` !

369−

370−```haskell

371−mpInsertion :: Manipulation Schema MpParams '[]

372−mpInsertion =

373− insertQuery_ #mp selectGroup -- we just have to write selectGroup !

374−```

375−

376−---

377−

378−_Inserting a Member of Parliament_

379−# The query type

380−

381−- A query looks just like a `Manipulation`:

382−

383−```haskell

384−Query schema params returns

385−```

386−

387−- Returns use a special syntax, that demands names, nullability and types:

388−

389−```haskell

390−type ExampleReturnType = '[ "some_column" ::: 'NotNull 'PGuuid

391− , "other_column" ::: 'Null 'PGtext ]

392−```

393−

394−- It is not the same as the column definition we used in the schema. That one also expects that you specify, for each column, an eventual default:

395−

396−```haskell

397−type ExampleSchemaCols =

398− '[ "some_column" ::: 'NoDef :=> 'NotNull 'PGuuid

399− , "other_column" ::: 'NoDef :=> 'Null 'PGtext ]

400−```

401−

402−---

403−

404−_Inserting a Member of Parliament_

405−# Don't rewrite column definitions

406−

407−- We want our return type to be "all columns from table MP expressed as return type".

408−

409−- But we cannot reuse our neat `MpCols` alias, since the type do not match as we've just seen.

410−

411−- Hopefully, there's a neat Type Family that will let you convert any table you defined to the type of the equivalent row: `TableToRow`.

412−

413−- We finally have the signature for our SELECT query.

414−

415−```haskell

416−selectGroup :: Query Schema MpParams (TableToRow MemberOfParliament)

417−```

418−

419−---

420−

421−_Inserting a Member of Parliament_

422−# Our final Select query

423−

424−- Our intermediate query looks like this:

425−

426−```haskell

427−selectGroup =

428− select

429− ( param @1 `as` #mp_id

430− :* param @2 `as` #first_name

431− :* param @3 `as` #last_name

432− :* #groupp ! #groupp_id `as` #mp_group

433− )

434− ( from (table #groupp)

435− & where_ ( #groupp ! #name .== param @4 )

436− )

437−```

438−

439−- The first three columns are constant defined through our params;

440−

441−- ... we alias the column name using `as`...

442−

443−- ... and when we need the result from the table we use the `#table ! #column` syntax.

444−

445−- We'll go back to the "from" block later.

446−

447−---

448−

449−# Dealing with the connection context

450−

451−- Queries are runned in a connection context:

452−

453− * When dealing with a single-connection context, use the type `PQ`.

454−

455− * When dealing with a pool of connection, use the type `PoolPQ`.

456−

457−- Or get rid of the context and use `mtl` style, with the typeclass `MonadPQ`.

458−

459−- We'll use that to demonstrate how to actually run our queries.

460−

461−---

462−

463−# Inserting a whole group

464−

465−```haskell

466−insertGroup :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()

467−insertGroup g@(Group name _) = do

468− uuid' <- liftBase nextRandom

469− void $ manipulateParams groupInsertion (uuid', name)

470− insertMps g

471−```

472−

473−- Remember that we defined a group as a name and a list of MPs.

474−

475−- We are in `MonadBaseControl`, so we cannot use `liftIO`, we need `liftBase`.

476−

477−- To perform a simple insertion, use `manipulateParams`. It takes into parameter

478−instances of `ToParam`, but you will typically use tuples or Generic-SOP.

479−

480−---

481−

482−# Inserting a bunch of MPs

483−

484−```haskell

485−insertMps :: (MonadPQ Schema m, MonadBaseControl IO m) => Group -> m ()

486−insertMps (Group groupName mps) =

487− let tuplify Mp{..} = (, firstName, lastName, groupName) <$> nextRandom

488− params = traverse tuplify mps

489− in void $ liftBase params >>= traversePrepared mpInsertion

490−```

491−

492−- This time, we want to do a `preparedStatement`. We'll use `traversePrepare`

493−which behaves like `manipulateParams`, but expect a list of `ToParam`

494−instances.

495−

496−- We build our tuple manually again, mostly because we want to generate UUID on

497−the fly and we don't want to have them in our model.

498−

499−---

500−

501−# Inserting a whole parliament

502−

503−```haskell

504−insertParliament ::

505− (MonadPQ Schema m, MonadBaseControl IO m) => Parliament -> m ()

506−insertParliament = traverse_ insertGroup

507−```

508−

509−- That's simple enough !

510−

511−- If we want to be a bit safer, though, we can wrap this call in a

512−`transactionally_` function, which will put all that in a transaction.

513−

514−---

515−

516−![Very simple](https://media1.tenor.com/images/0188c63209aced59f1583e1ca94e509e/tenor.gif?itemid=3550689)

517−

518−

519−---

520−

521−# Part III. Selects

522−

523−---

524−

525−# Composable queries

526−

527−- Building basic queries is easy, and is well documented.

528−

529−- However, the real interest of a tool like Squeal is in DRYness, and the documentation is still lacking in "how-to" related to composability.

530−

531−- I'll build an example showing how column selections and from clause can be factorized.

532−

533−- We want to write two queries:

534−

535− * One to get all members of a specific group.

536−

537− * One to get all the parliament.

538−

539−---

540−

541−# Decomposing a `Query`

542−

543−- A query typically stars with `select` (variants are available).

544−

545−- It then takes:

546−

547− * A heterogenous list of fields with a scary signature;

548−

549− * A virtual table (the from clause and filter clauses), called a `TableExpression`.

550−

551−- And return fields. Ours will look like this:

552−

553−```haskell

554−type GroupRowResult =

555− '[ "groupName" ::: 'NotNull 'PGtext

556− , "firstName" ::: 'NotNull 'PGtext

557− , "lastName" ::: 'NotNull 'PGtext ]

558−```

559−

560−---

561−

562−# The Table Expression

563−

564−- It necessarily contains a `fromClause` (table, view or subquery, plus optional joins).

565−

566−- You can add where, groups, "HAVING" clause, order, etc.

567−

568−- `from` creates a basic `TableExpression` that you extend through various function to add clauses.

569−

570−- For our queries, we will share a common `FromClause`.

571−

572−---

573−

574−# The From Clause

575−

576−```

577−FromClause schema params from

578−```

579−

580−- We need Schema, input parameters and a `FromType` giving the available fields of the expression.

581−

582−- In our case, we'll join the table `mp` and the table `groupp`, meaning the `from` will be all fields of these tables.

583−

584−- We can use `TableToRow` to be more DRY:

585−

586−```haskell

587−type BaseParliamentSelection =

588− '[ "g" ::: TableToRow GroupCols

589− , "m" ::: TableToRow MpCols ]

590−```

591−

592−> _note_ We've also put everything with table aliases: "g" and "m".

593−

594−---

595−

596−# Writing our from clause

597−

598−```haskell

599−baseParliamentTables ::

600− FromClause Schema (param :: [NullityType]) BaseParliamentSelection

601−baseParliamentTables =

602− table

603− (#groupp `as` #g)

604− & innerJoin

605− (table (#mp `as` #m))

606− (#m ! #mp_group .== #g ! #groupp_id)

607−```

608−

609−- When picking "from" something, you need to specify the type with a function: `table` for a table, `view` for a view, etc.

610−

611−- All joins are available. `innerJoin` is the most basic one. It takes the joined table and the joining condition.

612−

613−- We have to specifiy the type of `param` (current limitation of the lib), even though _any_ params will be compatible with this, so we can plug `where` clauses depending on params should we need to !

614−

615−---

616−

617−# Typing the common selection

618−

619−- Both our querie will need the same fields. This has to be factorized too.

620−

621−- The scary signature of selection fields:

622−

623−```haskell

624−NP (Aliased (Expression schema from grouping params)) cols

625−```

626−

627−- `NP` is for heterogenous lists ("n-ary product").

628−

629−- `from` is the virtual table type, so our `BaseParliamentSelection`.

630−

631−- `grouping` is there to make a distinction between aggregated / unaggregated queries.

632−

633−- And finally, cols is the return type.

634−

635−---

636−

637−# Our common selection

638−

639−```haskell

640−groupSelection ::

641− NP (Aliased (Expression Schema BaseParliamentSelection 'Ungrouped param))

642− GroupRowResult

643−groupSelection =

644− #g ! #name `as` #groupName

645− :* #m ! #first_name `as` #firstName

646− :* #m ! #last_name `as` #lastName

647−```

648−

649−- I hope you like big signatures.

650−

651−- But it's what let GHC checks that all alias and columns are available.

652−

653−- And that you're returning what you really intend to return.

654−

655−---

656−

657−# Putting it all together

658−

659−```haskell

660−selectParliament :: Query Schema '[] GroupRowResult

661−selectParliament =

662− select groupSelection (from baseParliamentTables)

663−```

664−

665−```haskell

666−selectGroupMembers :: Query Schema '[ 'NotNull 'PGtext] GroupRowResult

667−selectGroupMembers =

668− select groupSelection

669− (from baseParliamentTables

670− & where_ (#g ! #name .== param @1))

671−```

672−

673−- That is fairly DRY. And _entirely typesafe_.

674−

675−---

676−

677−# Actually fetching the data

678−

679−- We'll build an intermediary datatype representing our rows.

680−

681−- We'll make it match our row.

682−

683−- And we'll add generic-SOP so that we can build them from query results.

684−

685−```haskell

686−type GroupRowResult =

687− '[ "groupName" ::: 'NotNull 'PGtext

688− , "firstName" ::: 'NotNull 'PGtext

689− , "lastName" ::: 'NotNull 'PGtext ]

690−```

691−

692−```haskell

693−data GroupRow =

694− GroupRow { groupName :: Text

695− , firstName :: Text

696− , lastName :: Text }

697− deriving (Generic)

698−

699−instance SOP.Generic GroupRow

700−instance SOP.HasDatatypeInfo GroupRow

701−```

702−

703−---

704−

705−# Aggregate result logic

706−

707−- We will get tabular, SQL data.

708−

709−- Our results will be `[GroupRow]`.

710−

711−- We'll build `Groups` from this:

712−

713−```haskell

714−buildGroup :: NE.NonEmpty GroupRow -> Group

715−buildGroup grs =

716− let buildMP (GroupRow _ f l) = Mp f l

717− name = groupName . NE.head $ grs

718− members = NE.toList (buildMP <$> grs)

719− in Group{..}

720−

721−rowToGroups :: [GroupRow] -> [Group]

722−rowToGroups =

723− let grouped = fmap NE.fromList . L.groupBy ((==) `on` groupName)

724− in fmap buildGroup . grouped

725−```

726−

727−---

728−

729−# Finally calling our queries

730−

731−- Query with params will use `runQueryParams`.

732−

733−- Query without params will use `runQuery`.

734−

735−- Result is inside a `MonadPQ` and of type `K` from generic-sop.

736−

737−- You get your actual result using `getRows`. Exemple:

738−

739−```haskell

740−getParliament :: (MonadPQ Schema m, MonadBaseControl IO m) => m [Group]

741−getParliament = do

742− res <- runQuery selectParliament

743− rows <- getRows res

744− pure $ rowToGroups rows

745−```

746−

747−- In real life of course you'll write:

748−

749−```haskell

750−getParliament =

751− rowToGroups <$> (runQuery selectParliament >>= getRows)

752−```

753−

754−---

755−

756−# Our query with params

757−

758−```haskell

759−getGroupMembers ::

760− (MonadPQ Schema m, MonadBaseControl IO m) => Text -> m (Maybe Group)

761−getGroupMembers =

762− listToMaybe . rowToGroups <$>

763− (runQueryParams selectGroupMembers (Only t) >>= getRows)

764−```

765−

766−- And that's it.

767−

768−---

769−

770−![Eazy](https://media.tenor.com/images/8fc7c4077efe11b4a3a3b9ae4e643e87/tenor.gif)

771−

772−---

773−

774−# Conclusion

775−

776−---

777−

778−# Pros & Cons

779−

780−- Not everything is included: some cool stuff like array_agg and window functions are not available yet.

781−

782−- But development is _very_ active. `IN` clauses were missing but were added in the 4.0 released recently.

783−

784−- It's bleeding edge. You need latest LTS to be comfortable and psql >= 9.5.

785−

786−- It's Postgres-only but I would say that's a feature. Multi-DB tools are even more complex.

787−

788−- The author & maintainer is <3.

789−

790−- Typesafe. 'nuff said.

791−

792−---

793−

794−# Thank you !

stack.yaml+1−6

@@ -1,8 +1,3 @@

1−resolver: nightly-2019-07-14

1+resolver: lts-11.1

2packages:

3- squeal-postgresql

4−

5−extra-deps:

6−- unliftio-pool-0.2.1.0

7−- github: morphismtech/free-categories

8− commit: c0e555fbefb5c21619e532264c4dfeac556d0630