@@ -19,7 +19,6 @@ Squeal data definition language.
1919 , GADTs
2020 , LambdaCase
2121 , MultiParamTypeClasses
22− , OverloadedLabels
2322 , OverloadedStrings
2423 , RankNTypes
2524 , ScopedTypeVariables
@@ -27,7 +26,6 @@ Squeal data definition language.
2726 , TypeInType
2827 , TypeOperators
2928 , UndecidableSuperClasses
30− , UndecidableInstances
3129#-}
3230
3331module Squeal.PostgreSQL.Definition
@@ -35,16 +33,81 @@ module Squeal.PostgreSQL.Definition
3533 Definition (..)
3634 , (>>>)
3735 , manipDefinition
36+ -- * Tables
37+ -- ** Create
38+ , createSchema
39+ , createSchemaIfNotExists
40+ , createTable
41+ , createTableIfNotExists
42+ , createView
43+ , createTypeEnum
44+ , createTypeEnumFrom
45+ , createTypeComposite
46+ , createTypeCompositeFrom
47+ , FieldTyped (..)
48+ , createDomain
49+ , createTypeRange
50+ , createIndex
51+ , TableConstraintExpression (..)
52+ , check
53+ , unique
54+ , primaryKey
55+ , foreignKey
56+ , ForeignKeyed
57+ , OnDeleteClause (..)
58+ , OnUpdateClause (..)
59+ -- ** Drop
60+ , dropSchema
61+ , dropTable
62+ , dropView
63+ , dropType
64+ -- ** Alter
65+ , alterTable
66+ , alterTableRename
67+ , AlterTable (..)
68+ , addConstraint
69+ , dropConstraint
70+ , AddColumn (..)
71+ , dropColumn
72+ , renameColumn
73+ , alterColumn
74+ , AlterColumn (..)
75+ , setDefault
76+ , dropDefault
77+ , setNotNull
78+ , dropNotNull
79+ , alterType
80+ -- * Columns
81+ , ColumnTypeExpression (..)
82+ , nullable
83+ , notNullable
84+ , default_
85+ , serial2
86+ , smallserial
87+ , serial4
88+ , serial
89+ , serial8
90+ , bigserial
3891 ) where
3992
4093import Control.Category
4194import Control.DeepSeq
4295import Data.ByteString
4396import Data.Monoid
97+import GHC.TypeLits
4498import Prelude hiding ((.), id)
4599
100+import qualified Generics.SOP as SOP
46101import qualified GHC.Generics as GHC
47102
103+import Squeal.PostgreSQL.Alias
104+import Squeal.PostgreSQL.Expression
105+import Squeal.PostgreSQL.Expression.Logic
106+import Squeal.PostgreSQL.Expression.Sort
107+import Squeal.PostgreSQL.Expression.Type
108+import Squeal.PostgreSQL.List
109+import Squeal.PostgreSQL.PG
110+import Squeal.PostgreSQL.Query
48111import Squeal.PostgreSQL.Manipulation
49112import Squeal.PostgreSQL.Render
50113import Squeal.PostgreSQL.Schema
@@ -80,3 +143,1039 @@ manipDefinition
80143 -- ^ no input or output
81144 -> Definition schemas schemas
82145manipDefinition = UnsafeDefinition . (<> ";") . renderSQL
146+
147+{-----------------------------------------
148+CREATE statements
149+-----------------------------------------}
150+
151+{- |
152+`createSchema` enters a new schema into the current database.
153+The schema name must be distinct from the name of any existing schema
154+in the current database.
155+
156+A schema is essentially a namespace: it contains named objects
157+(tables, data types, functions, and operators) whose names
158+can duplicate those of other objects existing in other schemas.
159+Named objects are accessed by `QualifiedAlias`es with the schema
160+name as a prefix.
161+-}
162+createSchema
163+ :: KnownSymbol sch
164+ => Alias sch
165+ -> Definition schemas (Create sch '[] schemas)
166+createSchema sch = UnsafeDefinition $
167+ "CREATE" <+> "SCHEMA" <+> renderSQL sch <> ";"
168+
169+{- | Idempotent version of `createSchema`. -}
170+createSchemaIfNotExists
171+ :: (KnownSymbol sch, Has sch schemas schema)
172+ => Alias sch
173+ -> Definition schemas schemas
174+createSchemaIfNotExists sch = UnsafeDefinition $
175+ "CREATE" <+> "SCHEMA" <+> "IF" <+> "NOT" <+> "EXISTS"
176+ <+> renderSQL sch <> ";"
177+
178+{- | `createTable` adds a table to the schema.
179+
180+>>> :set -XOverloadedLabels
181+>>> :{
182+type Table = '[] :=>
183+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4
184+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
185+:}
186+
187+>>> :{
188+let
189+ setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table])
190+ setup = createTable #tab
191+ (nullable int `as` #a :* nullable real `as` #b) Nil
192+in printSQL setup
193+:}
194+CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
195+-}
196+createTable
197+ :: ( KnownSymbol sch
198+ , KnownSymbol tab
199+ , columns ~ (col ': cols)
200+ , SOP.SListI columns
201+ , SOP.SListI constraints
202+ , Has sch schemas0 schema0
203+ , schemas1 ~ Alter sch (Create tab ('Table (constraints :=> columns)) schema0) schemas0 )
204+ => QualifiedAlias sch tab -- ^ the name of the table to add
205+ -> NP (Aliased (ColumnTypeExpression schemas0)) columns
206+ -- ^ the names and datatype of each column
207+ -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
208+ -- ^ constraints that must hold for the table
209+ -> Definition schemas0 schemas1
210+createTable tab columns constraints = UnsafeDefinition $
211+ "CREATE TABLE" <+> renderCreation tab columns constraints
212+
213+{-| `createTableIfNotExists` creates a table if it doesn't exist, but does not add it to the schema.
214+Instead, the schema already has the table so if the table did not yet exist, the schema was wrong.
215+`createTableIfNotExists` fixes this. Interestingly, this property makes it an idempotent in
216+the `Category` of `Definition`s.
217+
218+>>> :set -XOverloadedLabels -XTypeApplications
219+>>> :{
220+type Table = '[] :=>
221+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4
222+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
223+:}
224+
225+>>> type Schemas = Public '["tab" ::: 'Table Table]
226+
227+>>> :{
228+let
229+ setup :: Definition Schemas Schemas
230+ setup = createTableIfNotExists #tab
231+ (nullable int `as` #a :* nullable real `as` #b) Nil
232+in printSQL setup
233+:}
234+CREATE TABLE IF NOT EXISTS "tab" ("a" int NULL, "b" real NULL);
235+-}
236+createTableIfNotExists
237+ :: ( Has sch schemas schema
238+ , Has tab schema ('Table (constraints :=> columns))
239+ , SOP.SListI columns
240+ , SOP.SListI constraints )
241+ => QualifiedAlias sch tab -- ^ the name of the table to add
242+ -> NP (Aliased (ColumnTypeExpression schemas)) columns
243+ -- ^ the names and datatype of each column
244+ -> NP (Aliased (TableConstraintExpression sch tab schemas)) constraints
245+ -- ^ constraints that must hold for the table
246+ -> Definition schemas schemas
247+createTableIfNotExists tab columns constraints = UnsafeDefinition $
248+ "CREATE TABLE IF NOT EXISTS"
249+ <+> renderCreation tab columns constraints
250+
251+-- helper function for `createTable` and `createTableIfNotExists`
252+renderCreation
253+ :: ( KnownSymbol sch
254+ , KnownSymbol tab
255+ , SOP.SListI columns
256+ , SOP.SListI constraints )
257+ => QualifiedAlias sch tab -- ^ the name of the table to add
258+ -> NP (Aliased (ColumnTypeExpression schemas0)) columns
259+ -- ^ the names and datatype of each column
260+ -> NP (Aliased (TableConstraintExpression sch tab schemas1)) constraints
261+ -- ^ constraints that must hold for the table
262+ -> ByteString
263+renderCreation tab columns constraints = renderSQL tab
264+ <+> parenthesized
265+ ( renderCommaSeparated renderColumnDef columns
266+ <> ( case constraints of
267+ Nil -> ""
268+ _ -> ", " <>
269+ renderCommaSeparated renderConstraint constraints ) )
270+ <> ";"
271+ where
272+ renderColumnDef :: Aliased (ColumnTypeExpression schemas) x -> ByteString
273+ renderColumnDef (ty `As` column) =
274+ renderSQL column <+> renderColumnTypeExpression ty
275+ renderConstraint
276+ :: Aliased (TableConstraintExpression sch tab schemas) constraint
277+ -> ByteString
278+ renderConstraint (constraint `As` alias) =
279+ "CONSTRAINT" <+> renderSQL alias <+> renderSQL constraint
280+
281+-- | Data types are a way to limit the kind of data that can be stored in a
282+-- table. For many applications, however, the constraint they provide is
283+-- too coarse. For example, a column containing a product price should
284+-- probably only accept positive values. But there is no standard data type
285+-- that accepts only positive numbers. Another issue is that you might want
286+-- to constrain column data with respect to other columns or rows.
287+-- For example, in a table containing product information,
288+-- there should be only one row for each product number.
289+-- `TableConstraint`s give you as much control over the data in your tables
290+-- as you wish. If a user attempts to store data in a column that would
291+-- violate a constraint, an error is raised. This applies
292+-- even if the value came from the default value definition.
293+newtype TableConstraintExpression
294+ (sch :: Symbol)
295+ (tab :: Symbol)
296+ (schemas :: SchemasType)
297+ (constraint :: TableConstraint)
298+ = UnsafeTableConstraintExpression
299+ { renderTableConstraintExpression :: ByteString }
300+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
301+instance RenderSQL
302+ (TableConstraintExpression sch tab schemas constraint) where
303+ renderSQL = renderTableConstraintExpression
304+
305+{-| A `check` constraint is the most generic `TableConstraint` type.
306+It allows you to specify that the value in a certain column must satisfy
307+a Boolean (truth-value) expression.
308+
309+>>> :{
310+type Schema = '[
311+ "tab" ::: 'Table ('[ "inequality" ::: 'Check '["a","b"]] :=> '[
312+ "a" ::: 'NoDef :=> 'NotNull 'PGint4,
313+ "b" ::: 'NoDef :=> 'NotNull 'PGint4
314+ ])]
315+:}
316+
317+>>> :{
318+let
319+ definition :: Definition (Public '[]) (Public Schema)
320+ definition = createTable #tab
321+ ( (int & notNullable) `as` #a :*
322+ (int & notNullable) `as` #b )
323+ ( check (#a :* #b) (#a .> #b) `as` #inequality )
324+:}
325+
326+>>> printSQL definition
327+CREATE TABLE "tab" ("a" int NOT NULL, "b" int NOT NULL, CONSTRAINT "inequality" CHECK (("a" > "b")));
328+-}
329+check
330+ :: ( Has sch schemas schema
331+ , Has tab schema ('Table table)
332+ , HasAll aliases (TableToRow table) subcolumns )
333+ => NP Alias aliases
334+ -- ^ specify the subcolumns which are getting checked
335+ -> (forall t. Condition '[] '[] 'Ungrouped schemas '[] '[t ::: subcolumns])
336+ -- ^ a closed `Condition` on those subcolumns
337+ -> TableConstraintExpression sch tab schemas ('Check aliases)
338+check _cols condition = UnsafeTableConstraintExpression $
339+ "CHECK" <+> parenthesized (renderSQL condition)
340+
341+{-| A `unique` constraint ensure that the data contained in a column,
342+or a group of columns, is unique among all the rows in the table.
343+
344+>>> :{
345+type Schema = '[
346+ "tab" ::: 'Table( '[ "uq_a_b" ::: 'Unique '["a","b"]] :=> '[
347+ "a" ::: 'NoDef :=> 'Null 'PGint4,
348+ "b" ::: 'NoDef :=> 'Null 'PGint4
349+ ])]
350+:}
351+
352+>>> :{
353+let
354+ definition :: Definition (Public '[]) (Public Schema)
355+ definition = createTable #tab
356+ ( (int & nullable) `as` #a :*
357+ (int & nullable) `as` #b )
358+ ( unique (#a :* #b) `as` #uq_a_b )
359+:}
360+
361+>>> printSQL definition
362+CREATE TABLE "tab" ("a" int NULL, "b" int NULL, CONSTRAINT "uq_a_b" UNIQUE ("a", "b"));
363+-}
364+unique
365+ :: ( Has sch schemas schema
366+ , Has tab schema('Table table)
367+ , HasAll aliases (TableToRow table) subcolumns )
368+ => NP Alias aliases
369+ -- ^ specify subcolumns which together are unique for each row
370+ -> TableConstraintExpression sch tab schemas ('Unique aliases)
371+unique columns = UnsafeTableConstraintExpression $
372+ "UNIQUE" <+> parenthesized (renderSQL columns)
373+
374+{-| A `primaryKey` constraint indicates that a column, or group of columns,
375+can be used as a unique identifier for rows in the table.
376+This requires that the values be both unique and not null.
377+
378+>>> :{
379+type Schema = '[
380+ "tab" ::: 'Table ('[ "pk_id" ::: 'PrimaryKey '["id"]] :=> '[
381+ "id" ::: 'Def :=> 'NotNull 'PGint4,
382+ "name" ::: 'NoDef :=> 'NotNull 'PGtext
383+ ])]
384+:}
385+
386+>>> :{
387+let
388+ definition :: Definition (Public '[]) (Public Schema)
389+ definition = createTable #tab
390+ ( serial `as` #id :*
391+ (text & notNullable) `as` #name )
392+ ( primaryKey #id `as` #pk_id )
393+:}
394+
395+>>> printSQL definition
396+CREATE TABLE "tab" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_id" PRIMARY KEY ("id"));
397+-}
398+primaryKey
399+ :: ( Has sch schemas schema
400+ , Has tab schema ('Table table)
401+ , HasAll aliases (TableToColumns table) subcolumns
402+ , AllNotNull subcolumns )
403+ => NP Alias aliases
404+ -- ^ specify the subcolumns which together form a primary key.
405+ -> TableConstraintExpression sch tab schemas ('PrimaryKey aliases)
406+primaryKey columns = UnsafeTableConstraintExpression $
407+ "PRIMARY KEY" <+> parenthesized (renderSQL columns)
408+
409+{-| A `foreignKey` specifies that the values in a column
410+(or a group of columns) must match the values appearing in some row of
411+another table. We say this maintains the referential integrity
412+between two related tables.
413+
414+>>> :{
415+type Schema =
416+ '[ "users" ::: 'Table (
417+ '[ "pk_users" ::: 'PrimaryKey '["id"] ] :=>
418+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
419+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
420+ ])
421+ , "emails" ::: 'Table (
422+ '[ "pk_emails" ::: 'PrimaryKey '["id"]
423+ , "fk_user_id" ::: 'ForeignKey '["user_id"] "users" '["id"]
424+ ] :=>
425+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
426+ , "user_id" ::: 'NoDef :=> 'NotNull 'PGint4
427+ , "email" ::: 'NoDef :=> 'Null 'PGtext
428+ ])
429+ ]
430+:}
431+
432+>>> :{
433+let
434+ setup :: Definition (Public '[]) (Public Schema)
435+ setup =
436+ createTable #users
437+ ( serial `as` #id :*
438+ (text & notNullable) `as` #name )
439+ ( primaryKey #id `as` #pk_users ) >>>
440+ createTable #emails
441+ ( serial `as` #id :*
442+ (int & notNullable) `as` #user_id :*
443+ (text & nullable) `as` #email )
444+ ( primaryKey #id `as` #pk_emails :*
445+ foreignKey #user_id #users #id
446+ OnDeleteCascade OnUpdateCascade `as` #fk_user_id )
447+in printSQL setup
448+:}
449+CREATE TABLE "users" ("id" serial, "name" text NOT NULL, CONSTRAINT "pk_users" PRIMARY KEY ("id"));
450+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);
451+
452+A `foreignKey` can even be a table self-reference.
453+
454+>>> :{
455+type Schema =
456+ '[ "employees" ::: 'Table (
457+ '[ "employees_pk" ::: 'PrimaryKey '["id"]
458+ , "employees_employer_fk" ::: 'ForeignKey '["employer_id"] "employees" '["id"]
459+ ] :=>
460+ '[ "id" ::: 'Def :=> 'NotNull 'PGint4
461+ , "name" ::: 'NoDef :=> 'NotNull 'PGtext
462+ , "employer_id" ::: 'NoDef :=> 'Null 'PGint4
463+ ])
464+ ]
465+:}
466+
467+>>> :{
468+let
469+ setup :: Definition (Public '[]) (Public Schema)
470+ setup =
471+ createTable #employees
472+ ( serial `as` #id :*
473+ (text & notNullable) `as` #name :*
474+ (integer & nullable) `as` #employer_id )
475+ ( primaryKey #id `as` #employees_pk :*
476+ foreignKey #employer_id #employees #id
477+ OnDeleteCascade OnUpdateCascade `as` #employees_employer_fk )
478+in printSQL setup
479+:}
480+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);
481+-}
482+foreignKey
483+ :: (ForeignKeyed schemas sch schema child parent
484+ table reftable
485+ columns refcolumns
486+ constraints cols
487+ reftys tys )
488+ => NP Alias columns
489+ -- ^ column or columns in the table
490+ -> Alias parent
491+ -- ^ reference table
492+ -> NP Alias refcolumns
493+ -- ^ reference column or columns in the reference table
494+ -> OnDeleteClause
495+ -- ^ what to do when reference is deleted
496+ -> OnUpdateClause
497+ -- ^ what to do when reference is updated
498+ -> TableConstraintExpression sch child schemas
499+ ('ForeignKey columns parent refcolumns)
500+foreignKey keys parent refs ondel onupd = UnsafeTableConstraintExpression $
501+ "FOREIGN KEY" <+> parenthesized (renderSQL keys)
502+ <+> "REFERENCES" <+> renderSQL parent
503+ <+> parenthesized (renderSQL refs)
504+ <+> renderSQL ondel
505+ <+> renderSQL onupd
506+
507+-- | A constraint synonym between types involved in a foreign key constraint.
508+type ForeignKeyed schemas
509+ sch
510+ schema
511+ child parent
512+ table reftable
513+ columns refcolumns
514+ constraints cols
515+ reftys tys =
516+ ( Has sch schemas schema
517+ , Has child schema ('Table table)
518+ , Has parent schema ('Table reftable)
519+ , HasAll columns (TableToColumns table) tys
520+ , reftable ~ (constraints :=> cols)
521+ , HasAll refcolumns cols reftys
522+ , SOP.AllZip SamePGType tys reftys
523+ , Uniquely refcolumns constraints )
524+
525+-- | `OnDeleteClause` indicates what to do with rows that reference a deleted row.
526+data OnDeleteClause
527+ = OnDeleteNoAction
528+ -- ^ if any referencing rows still exist when the constraint is checked,
529+ -- an error is raised
530+ | OnDeleteRestrict -- ^ prevents deletion of a referenced row
531+ | OnDeleteCascade
532+ -- ^ specifies that when a referenced row is deleted,
533+ -- row(s) referencing it should be automatically deleted as well
534+ deriving (GHC.Generic,Show,Eq,Ord)
535+instance NFData OnDeleteClause
536+-- | Render `OnDeleteClause`.
537+instance RenderSQL OnDeleteClause where
538+ renderSQL = \case
539+ OnDeleteNoAction -> "ON DELETE NO ACTION"
540+ OnDeleteRestrict -> "ON DELETE RESTRICT"
541+ OnDeleteCascade -> "ON DELETE CASCADE"
542+
543+-- | Analagous to `OnDeleteClause` there is also `OnUpdateClause` which is invoked
544+-- when a referenced column is changed (updated).
545+data OnUpdateClause
546+ = OnUpdateNoAction
547+ -- ^ if any referencing rows has not changed when the constraint is checked,
548+ -- an error is raised
549+ | OnUpdateRestrict -- ^ prevents update of a referenced row
550+ | OnUpdateCascade
551+ -- ^ the updated values of the referenced column(s) should be copied
552+ -- into the referencing row(s)
553+ deriving (GHC.Generic,Show,Eq,Ord)
554+instance NFData OnUpdateClause
555+
556+-- | Render `OnUpdateClause`.
557+instance RenderSQL OnUpdateClause where
558+ renderSQL = \case
559+ OnUpdateNoAction -> "ON UPDATE NO ACTION"
560+ OnUpdateRestrict -> "ON UPDATE RESTRICT"
561+ OnUpdateCascade -> "ON UPDATE CASCADE"
562+
563+{-----------------------------------------
564+DROP statements
565+-----------------------------------------}
566+
567+-- | >>> :{
568+-- let
569+-- definition :: Definition '["muh_schema" ::: schema, "public" ::: public] '["public" ::: public]
570+-- definition = dropSchema #muh_schema
571+-- :}
572+--
573+-- >>> printSQL definition
574+-- DROP SCHEMA "muh_schema";
575+dropSchema
576+ :: Has sch schemas schema
577+ => Alias sch
578+ -> Definition schemas (Drop sch schemas)
579+dropSchema sch = UnsafeDefinition $ "DROP SCHEMA" <+> renderSQL sch <> ";"
580+
581+-- | `dropTable` removes a table from the schema.
582+--
583+-- >>> :{
584+-- let
585+-- definition :: Definition '["public" ::: '["muh_table" ::: 'Table t]] (Public '[])
586+-- definition = dropTable #muh_table
587+-- :}
588+--
589+-- >>> printSQL definition
590+-- DROP TABLE "muh_table";
591+dropTable
592+ :: ( Has sch schemas schema
593+ , Has tab schema ('Table table))
594+ => QualifiedAlias sch tab -- ^ table to remove
595+ -> Definition schemas (Alter sch (Drop tab schema) schemas)
596+dropTable tab = UnsafeDefinition $ "DROP TABLE" <+> renderSQL tab <> ";"
597+
598+{-----------------------------------------
599+ALTER statements
600+-----------------------------------------}
601+
602+-- | `alterTable` changes the definition of a table from the schema.
603+alterTable
604+ :: (Has sch schemas schema, Has tab schema ('Table table0))
605+ => QualifiedAlias sch tab -- ^ table to alter
606+ -> AlterTable sch tab schemas table1 -- ^ alteration to perform
607+ -> Definition schemas (Alter sch (Alter tab ('Table table1) schema) schemas)
608+alterTable tab alteration = UnsafeDefinition $
609+ "ALTER TABLE"
610+ <+> renderSQL tab
611+ <+> renderAlterTable alteration
612+ <> ";"
613+
614+-- | `alterTableRename` changes the name of a table from the schema.
615+--
616+-- >>> printSQL $ alterTableRename #foo #bar
617+-- ALTER TABLE "foo" RENAME TO "bar";
618+alterTableRename
619+ :: (KnownSymbol table0, KnownSymbol table1)
620+ => Alias table0 -- ^ table to rename
621+ -> Alias table1 -- ^ what to rename it
622+ -> Definition schema (Rename table0 table1 schema)
623+alterTableRename table0 table1 = UnsafeDefinition $
624+ "ALTER TABLE" <+> renderSQL table0
625+ <+> "RENAME TO" <+> renderSQL table1 <> ";"
626+
627+-- | An `AlterTable` describes the alteration to perform on the columns
628+-- of a table.
629+newtype AlterTable
630+ (sch :: Symbol)
631+ (tab :: Symbol)
632+ (schemas :: SchemasType)
633+ (table :: TableType) =
634+ UnsafeAlterTable {renderAlterTable :: ByteString}
635+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
636+
637+-- | An `addConstraint` adds a table constraint.
638+--
639+-- >>> :{
640+-- let
641+-- definition :: Definition
642+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
643+-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: 'Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
644+-- definition = alterTable #tab (addConstraint #positive (check #col (#col .> 0)))
645+-- in printSQL definition
646+-- :}
647+-- ALTER TABLE "tab" ADD CONSTRAINT "positive" CHECK (("col" > 0));
648+addConstraint
649+ :: ( KnownSymbol alias
650+ , Has sch schemas schema
651+ , Has tab schema ('Table table0)
652+ , table0 ~ (constraints :=> columns)
653+ , table1 ~ (Create alias constraint constraints :=> columns) )
654+ => Alias alias
655+ -> TableConstraintExpression sch tab schemas constraint
656+ -- ^ constraint to add
657+ -> AlterTable sch tab schemas table1
658+addConstraint alias constraint = UnsafeAlterTable $
659+ "ADD" <+> "CONSTRAINT" <+> renderSQL alias
660+ <+> renderSQL constraint
661+
662+-- | A `dropConstraint` drops a table constraint.
663+--
664+-- >>> :{
665+-- let
666+-- definition :: Definition
667+-- '["public" ::: '["tab" ::: 'Table ('["positive" ::: Check '["col"]] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
668+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
669+-- definition = alterTable #tab (dropConstraint #positive)
670+-- in printSQL definition
671+-- :}
672+-- ALTER TABLE "tab" DROP CONSTRAINT "positive";
673+dropConstraint
674+ :: ( KnownSymbol constraint
675+ , Has sch schemas schema
676+ , Has tab schema ('Table table0)
677+ , table0 ~ (constraints :=> columns)
678+ , table1 ~ (Drop constraint constraints :=> columns) )
679+ => Alias constraint
680+ -- ^ constraint to drop
681+ -> AlterTable sch tab schemas table1
682+dropConstraint constraint = UnsafeAlterTable $
683+ "DROP" <+> "CONSTRAINT" <+> renderSQL constraint
684+
685+-- | An `AddColumn` is either @NULL@ or has @DEFAULT@.
686+class AddColumn ty where
687+ -- | `addColumn` adds a new column, initially filled with whatever
688+ -- default value is given or with @NULL@.
689+ --
690+ -- >>> :{
691+ -- let
692+ -- definition :: Definition
693+ -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
694+ -- '["public" ::: '["tab" ::: 'Table ('[] :=>
695+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
696+ -- , "col2" ::: 'Def :=> 'Null 'PGtext ])]]
697+ -- definition = alterTable #tab (addColumn #col2 (text & nullable & default_ "foo"))
698+ -- in printSQL definition
699+ -- :}
700+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL DEFAULT E'foo';
701+ --
702+ -- >>> :{
703+ -- let
704+ -- definition :: Definition
705+ -- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
706+ -- '["public" ::: '["tab" ::: 'Table ('[] :=>
707+ -- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
708+ -- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
709+ -- definition = alterTable #tab (addColumn #col2 (text & nullable))
710+ -- in printSQL definition
711+ -- :}
712+ -- ALTER TABLE "tab" ADD COLUMN "col2" text NULL;
713+ addColumn
714+ :: ( KnownSymbol column
715+ , Has sch schemas schema
716+ , Has tab schema ('Table table0)
717+ , table0 ~ (constraints :=> columns) )
718+ => Alias column -- ^ column to add
719+ -> ColumnTypeExpression schemas ty -- ^ type of the new column
720+ -> AlterTable sch tab schemas (constraints :=> Create column ty columns)
721+ addColumn column ty = UnsafeAlterTable $
722+ "ADD COLUMN" <+> renderSQL column <+> renderColumnTypeExpression ty
723+instance {-# OVERLAPPING #-} AddColumn ('Def :=> ty)
724+instance {-# OVERLAPPABLE #-} AddColumn ('NoDef :=> 'Null ty)
725+
726+-- | A `dropColumn` removes a column. Whatever data was in the column
727+-- disappears. Table constraints involving the column are dropped, too.
728+-- However, if the column is referenced by a foreign key constraint of
729+-- another table, PostgreSQL will not silently drop that constraint.
730+--
731+-- >>> :{
732+-- let
733+-- definition :: Definition
734+-- '["public" ::: '["tab" ::: 'Table ('[] :=>
735+-- '[ "col1" ::: 'NoDef :=> 'Null 'PGint4
736+-- , "col2" ::: 'NoDef :=> 'Null 'PGtext ])]]
737+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col1" ::: 'NoDef :=> 'Null 'PGint4])]]
738+-- definition = alterTable #tab (dropColumn #col2)
739+-- in printSQL definition
740+-- :}
741+-- ALTER TABLE "tab" DROP COLUMN "col2";
742+dropColumn
743+ :: ( KnownSymbol column
744+ , Has sch schemas schema
745+ , Has tab schema ('Table table0)
746+ , table0 ~ (constraints :=> columns)
747+ , table1 ~ (constraints :=> Drop column columns) )
748+ => Alias column -- ^ column to remove
749+ -> AlterTable sch tab schemas table1
750+dropColumn column = UnsafeAlterTable $
751+ "DROP COLUMN" <+> renderSQL column
752+
753+-- | A `renameColumn` renames a column.
754+--
755+-- >>> :{
756+-- let
757+-- definition :: Definition
758+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["foo" ::: 'NoDef :=> 'Null 'PGint4])]]
759+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["bar" ::: 'NoDef :=> 'Null 'PGint4])]]
760+-- definition = alterTable #tab (renameColumn #foo #bar)
761+-- in printSQL definition
762+-- :}
763+-- ALTER TABLE "tab" RENAME COLUMN "foo" TO "bar";
764+renameColumn
765+ :: ( KnownSymbol column0
766+ , KnownSymbol column1
767+ , Has sch schemas schema
768+ , Has tab schema ('Table table0)
769+ , table0 ~ (constraints :=> columns)
770+ , table1 ~ (constraints :=> Rename column0 column1 columns) )
771+ => Alias column0 -- ^ column to rename
772+ -> Alias column1 -- ^ what to rename the column
773+ -> AlterTable sch tab schemas table1
774+renameColumn column0 column1 = UnsafeAlterTable $
775+ "RENAME COLUMN" <+> renderSQL column0 <+> "TO" <+> renderSQL column1
776+
777+-- | An `alterColumn` alters a single column.
778+alterColumn
779+ :: ( KnownSymbol column
780+ , Has sch schemas schema
781+ , Has tab schema ('Table table0)
782+ , table0 ~ (constraints :=> columns)
783+ , Has column columns ty0
784+ , table1 ~ (constraints :=> Alter column ty1 columns))
785+ => Alias column -- ^ column to alter
786+ -> AlterColumn schemas ty0 ty1 -- ^ alteration to perform
787+ -> AlterTable sch tab schemas table1
788+alterColumn column alteration = UnsafeAlterTable $
789+ "ALTER COLUMN" <+> renderSQL column <+> renderAlterColumn alteration
790+
791+-- | An `AlterColumn` describes the alteration to perform on a single column.
792+newtype AlterColumn (schemas :: SchemasType) (ty0 :: ColumnType) (ty1 :: ColumnType) =
793+ UnsafeAlterColumn {renderAlterColumn :: ByteString}
794+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
795+
796+-- | A `setDefault` sets a new default for a column. Note that this doesn't
797+-- affect any existing rows in the table, it just changes the default for
798+-- future insert and update commands.
799+--
800+-- >>> :{
801+-- let
802+-- definition :: Definition
803+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
804+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
805+-- definition = alterTable #tab (alterColumn #col (setDefault 5))
806+-- in printSQL definition
807+-- :}
808+-- ALTER TABLE "tab" ALTER COLUMN "col" SET DEFAULT 5;
809+setDefault
810+ :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty -- ^ default value to set
811+ -> AlterColumn schemas (constraint :=> ty) ('Def :=> ty)
812+setDefault expression = UnsafeAlterColumn $
813+ "SET DEFAULT" <+> renderExpression expression
814+
815+-- | A `dropDefault` removes any default value for a column.
816+--
817+-- >>> :{
818+-- let
819+-- definition :: Definition
820+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'Def :=> 'Null 'PGint4])]]
821+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
822+-- definition = alterTable #tab (alterColumn #col dropDefault)
823+-- in printSQL definition
824+-- :}
825+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP DEFAULT;
826+dropDefault :: AlterColumn schemas ('Def :=> ty) ('NoDef :=> ty)
827+dropDefault = UnsafeAlterColumn $ "DROP DEFAULT"
828+
829+-- | A `setNotNull` adds a @NOT NULL@ constraint to a column.
830+-- The constraint will be checked immediately, so the table data must satisfy
831+-- the constraint before it can be added.
832+--
833+-- >>> :{
834+-- let
835+-- definition :: Definition
836+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
837+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
838+-- definition = alterTable #tab (alterColumn #col setNotNull)
839+-- in printSQL definition
840+-- :}
841+-- ALTER TABLE "tab" ALTER COLUMN "col" SET NOT NULL;
842+setNotNull
843+ :: AlterColumn schemas (constraint :=> 'Null ty) (constraint :=> 'NotNull ty)
844+setNotNull = UnsafeAlterColumn $ "SET NOT NULL"
845+
846+-- | A `dropNotNull` drops a @NOT NULL@ constraint from a column.
847+--
848+-- >>> :{
849+-- let
850+-- definition :: Definition
851+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
852+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'Null 'PGint4])]]
853+-- definition = alterTable #tab (alterColumn #col dropNotNull)
854+-- in printSQL definition
855+-- :}
856+-- ALTER TABLE "tab" ALTER COLUMN "col" DROP NOT NULL;
857+dropNotNull
858+ :: AlterColumn schemas (constraint :=> 'NotNull ty) (constraint :=> 'Null ty)
859+dropNotNull = UnsafeAlterColumn $ "DROP NOT NULL"
860+
861+-- | An `alterType` converts a column to a different data type.
862+-- This will succeed only if each existing entry in the column can be
863+-- converted to the new type by an implicit cast.
864+--
865+-- >>> :{
866+-- let
867+-- definition :: Definition
868+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGint4])]]
869+-- '["public" ::: '["tab" ::: 'Table ('[] :=> '["col" ::: 'NoDef :=> 'NotNull 'PGnumeric])]]
870+-- definition =
871+-- alterTable #tab (alterColumn #col (alterType (numeric & notNullable)))
872+-- in printSQL definition
873+-- :}
874+-- ALTER TABLE "tab" ALTER COLUMN "col" TYPE numeric NOT NULL;
875+alterType :: ColumnTypeExpression schemas ty -> AlterColumn schemas ty0 ty
876+alterType ty = UnsafeAlterColumn $ "TYPE" <+> renderColumnTypeExpression ty
877+
878+{- | Create a view.
879+>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]
880+>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]
881+>>> :{
882+let
883+ definition :: Definition
884+ '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]
885+ '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc" ::: 'View BC]]
886+ definition =
887+ createView #bc (select_ (#b :* #c) (from (table #abc)))
888+in printSQL definition
889+:}
890+CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";
891+-}
892+createView
893+ :: (KnownSymbol sch, KnownSymbol vw, Has sch schemas schema)
894+ => QualifiedAlias sch vw -- ^ the name of the view to add
895+ -> Query '[] '[] schemas '[] view -- ^ query
896+ -> Definition schemas (Alter sch (Create vw ('View view) schema) schemas)
897+createView alias query = UnsafeDefinition $
898+ "CREATE" <+> "VIEW" <+> renderSQL alias <+> "AS"
899+ <+> renderQuery query <> ";"
900+
901+-- | Drop a view.
902+--
903+-- >>> :{
904+-- let
905+-- definition :: Definition
906+-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
907+-- , "bc" ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]
908+-- '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]
909+-- definition = dropView #bc
910+-- in printSQL definition
911+-- :}
912+-- DROP VIEW "bc";
913+dropView
914+ :: (Has sch schemas schema, Has vw schema ('View view))
915+ => QualifiedAlias sch vw -- ^ view to remove
916+ -> Definition schemas (Alter sch (Drop vw schema) schemas)
917+dropView vw = UnsafeDefinition $ "DROP VIEW" <+> renderSQL vw <> ";"
918+
919+-- | Enumerated types are created using the `createTypeEnum` command, for example
920+--
921+-- >>> printSQL $ (createTypeEnum #mood (label @"sad" :* label @"ok" :* label @"happy") :: Definition (Public '[]) '["public" ::: '["mood" ::: 'Typedef ('PGenum '["sad","ok","happy"])]])
922+-- CREATE TYPE "mood" AS ENUM ('sad', 'ok', 'happy');
923+createTypeEnum
924+ :: (KnownSymbol enum, Has sch schemas schema, SOP.All KnownSymbol labels)
925+ => QualifiedAlias sch enum
926+ -- ^ name of the user defined enumerated type
927+ -> NP PGlabel labels
928+ -- ^ labels of the enumerated type
929+ -> Definition schemas (Alter sch (Create enum ('Typedef ('PGenum labels)) schema) schemas)
930+createTypeEnum enum labels = UnsafeDefinition $
931+ "CREATE" <+> "TYPE" <+> renderSQL enum <+> "AS" <+> "ENUM" <+>
932+ parenthesized (renderSQL labels) <> ";"
933+
934+-- | Enumerated types can also be generated from a Haskell type, for example
935+--
936+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
937+-- >>> instance SOP.Generic Schwarma
938+-- >>> instance SOP.HasDatatypeInfo Schwarma
939+-- >>> :{
940+-- let
941+-- createSchwarma :: Definition (Public '[]) '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]]
942+-- createSchwarma = createTypeEnumFrom @Schwarma #schwarma
943+-- in
944+-- printSQL createSchwarma
945+-- :}
946+-- CREATE TYPE "schwarma" AS ENUM ('Beef', 'Lamb', 'Chicken');
947+createTypeEnumFrom
948+ :: forall hask sch enum schemas schema.
949+ ( SOP.Generic hask
950+ , SOP.All KnownSymbol (LabelsPG hask)
951+ , KnownSymbol enum
952+ , Has sch schemas schema )
953+ => QualifiedAlias sch enum
954+ -- ^ name of the user defined enumerated type
955+ -> Definition schemas (Alter sch (Create enum ('Typedef (PG (Enumerated hask))) schema) schemas)
956+createTypeEnumFrom enum = createTypeEnum enum
957+ (SOP.hpure label :: NP PGlabel (LabelsPG hask))
958+
959+{- | `createTypeComposite` creates a composite type. The composite type is
960+specified by a list of attribute names and data types.
961+
962+>>> :{
963+type PGcomplex = 'PGcomposite
964+ '[ "real" ::: 'NotNull 'PGfloat8
965+ , "imaginary" ::: 'NotNull 'PGfloat8 ]
966+:}
967+
968+>>> :{
969+let
970+ setup :: Definition (Public '[]) '["public" ::: '["complex" ::: 'Typedef PGcomplex]]
971+ setup = createTypeComposite #complex
972+ (float8 `as` #real :* float8 `as` #imaginary)
973+in printSQL setup
974+:}
975+CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
976+-}
977+createTypeComposite
978+ :: (KnownSymbol ty, Has sch schemas schema, SOP.SListI fields)
979+ => QualifiedAlias sch ty
980+ -- ^ name of the user defined composite type
981+ -> NP (Aliased (TypeExpression schemas)) fields
982+ -- ^ list of attribute names and data types
983+ -> Definition schemas (Alter sch (Create ty ('Typedef ('PGcomposite fields)) schema) schemas)
984+createTypeComposite ty fields = UnsafeDefinition $
985+ "CREATE" <+> "TYPE" <+> renderSQL ty <+> "AS" <+> parenthesized
986+ (renderCommaSeparated renderField fields) <> ";"
987+ where
988+ renderField :: Aliased (TypeExpression schemas) x -> ByteString
989+ renderField (typ `As` alias) =
990+ renderSQL alias <+> renderSQL typ
991+
992+-- | Composite types can also be generated from a Haskell type, for example
993+--
994+-- >>> data Complex = Complex {real :: Double, imaginary :: Double} deriving GHC.Generic
995+-- >>> instance SOP.Generic Complex
996+-- >>> instance SOP.HasDatatypeInfo Complex
997+-- >>> type Schema = '["complex" ::: 'Typedef (PG (Composite Complex))]
998+-- >>> :{
999+-- let
1000+-- createComplex :: Definition (Public '[]) (Public Schema)
1001+-- createComplex = createTypeCompositeFrom @Complex #complex
1002+-- in
1003+-- printSQL createComplex
1004+-- :}
1005+-- CREATE TYPE "complex" AS ("real" float8, "imaginary" float8);
1006+createTypeCompositeFrom
1007+ :: forall hask sch ty schemas schema.
1008+ ( SOP.All (FieldTyped schemas) (RowPG hask)
1009+ , KnownSymbol ty
1010+ , Has sch schemas schema )
1011+ => QualifiedAlias sch ty
1012+ -- ^ name of the user defined composite type
1013+ -> Definition schemas (Alter sch (Create ty ( 'Typedef (PG (Composite hask))) schema) schemas)
1014+createTypeCompositeFrom ty = createTypeComposite ty
1015+ (SOP.hcpure (SOP.Proxy :: SOP.Proxy (FieldTyped schemas)) fieldtype
1016+ :: NP (Aliased (TypeExpression schemas)) (RowPG hask))
1017+
1018+{-|
1019+`createDomain` creates a new domain. A domain is essentially a data type
1020+with constraints (restrictions on the allowed set of values).
1021+
1022+Domains are useful for abstracting common constraints on fields
1023+into a single location for maintenance. For example, several tables might
1024+contain email address columns, all requiring the same `check` constraint
1025+to verify the address syntax. Define a domain rather than setting up
1026+each table's constraint individually.
1027+
1028+>>> :{
1029+let
1030+ createPositive :: Definition (Public '[]) (Public '["positive" ::: 'Typedef 'PGfloat4])
1031+ createPositive = createDomain #positive real (#value .> 0 .&& (#value & isNotNull))
1032+in printSQL createPositive
1033+:}
1034+CREATE DOMAIN "positive" AS real CHECK ((("value" > 0) AND "value" IS NOT NULL));
1035+-}
1036+createDomain
1037+ :: (Has sch schemas schema, KnownSymbol dom)
1038+ => QualifiedAlias sch dom
1039+ -> (forall null. TypeExpression schemas (null ty))
1040+ -> (forall tab. Condition '[] '[] 'Ungrouped schemas '[] '[tab ::: '["value" ::: 'Null ty]])
1041+ -> Definition schemas (Alter sch (Create dom ('Typedef ty) schema) schemas)
1042+createDomain dom ty condition =
1043+ UnsafeDefinition $ "CREATE DOMAIN" <+> renderSQL dom
1044+ <+> "AS" <+> renderTypeExpression ty
1045+ <+> "CHECK" <+> parenthesized (renderSQL condition) <> ";"
1046+
1047+{- |
1048+>>> :{
1049+let
1050+ createSmallIntRange :: Definition (Public '[]) (Public '["int2range" ::: 'Typedef ('PGrange 'PGint2)])
1051+ createSmallIntRange = createTypeRange #int2range int2
1052+in printSQL createSmallIntRange
1053+:}
1054+CREATE TYPE "int2range" AS RANGE (subtype = int2);
1055+-}
1056+createTypeRange
1057+ :: (Has sch schemas schema, KnownSymbol range)
1058+ => QualifiedAlias sch range
1059+ -> (forall null. TypeExpression schemas (null ty))
1060+ -> Definition schemas (Alter sch (Create range ('Typedef ('PGrange ty)) schema) schemas)
1061+createTypeRange range ty = UnsafeDefinition $
1062+ "CREATE" <+> "TYPE" <+> renderSQL range <+> "AS" <+> "RANGE" <+>
1063+ parenthesized ("subtype" <+> "=" <+> renderTypeExpression ty) <> ";"
1064+
1065+{- |
1066+>>> :{
1067+type Table = '[] :=>
1068+ '[ "a" ::: 'NoDef :=> 'Null 'PGint4
1069+ , "b" ::: 'NoDef :=> 'Null 'PGfloat4 ]
1070+:}
1071+
1072+>>> :{
1073+let
1074+ setup :: Definition (Public '[]) (Public '["tab" ::: 'Table Table, "ix" ::: 'Index])
1075+ setup =
1076+ createTable #tab (nullable int `as` #a :* nullable real `as` #b) Nil >>>
1077+ createIndex #ix #tab Gin [#a & AscNullsFirst, #b & AscNullsLast]
1078+in printSQL setup
1079+:}
1080+CREATE TABLE "tab" ("a" int NULL, "b" real NULL);
1081+CREATE INDEX "ix" ON "tab" USING gin (("a" ASC NULLS FIRST), ("b" ASC NULLS LAST));
1082+-}
1083+createIndex
1084+ :: (Has sch schemas schema, Has tab schema ('Table table), KnownSymbol ix)
1085+ => Alias ix
1086+ -> QualifiedAlias sch tab
1087+ -> IndexMethod
1088+ -> [SortExpression '[] '[] 'Ungrouped schemas '[] '[tab ::: TableToRow table]]
1089+ -> Definition schemas (Alter sch (Create ix 'Index schema) schemas)
1090+createIndex ix tab method cols = UnsafeDefinition $
1091+ "CREATE" <+> "INDEX" <+> renderSQL ix <+> "ON" <+> renderSQL tab
1092+ <+> "USING" <+> renderSQL method
1093+ <+> parenthesized (commaSeparated (parenthesized . renderSQL <$> cols))
1094+ <> ";"
1095+
1096+data IndexMethod
1097+ = Btree
1098+ | Hash
1099+ | Gist
1100+ | Spgist
1101+ | Gin
1102+ | Brin
1103+ deriving stock (Eq, Ord, Show, GHC.Generic)
1104+ deriving anyclass (SOP.HasDatatypeInfo, SOP.Generic)
1105+instance RenderSQL IndexMethod where
1106+ renderSQL = \case
1107+ Btree -> "btree"
1108+ Hash -> "hash"
1109+ Gist -> "gist"
1110+ Spgist -> "spgist"
1111+ Gin -> "gin"
1112+ Brin -> "brin"
1113+
1114+-- | Lift `PGTyped` to a field
1115+class FieldTyped schemas ty where
1116+ fieldtype :: Aliased (TypeExpression schemas) ty
1117+instance (KnownSymbol alias, PGTyped schemas ty)
1118+ => FieldTyped schemas (alias ::: ty) where
1119+ fieldtype = pgtype `As` Alias
1120+
1121+-- | Drop a type.
1122+--
1123+-- >>> data Schwarma = Beef | Lamb | Chicken deriving GHC.Generic
1124+-- >>> instance SOP.Generic Schwarma
1125+-- >>> instance SOP.HasDatatypeInfo Schwarma
1126+-- >>> printSQL (dropType #schwarma :: Definition '["public" ::: '["schwarma" ::: 'Typedef (PG (Enumerated Schwarma))]] (Public '[]))
1127+-- DROP TYPE "schwarma";
1128+dropType
1129+ :: (Has sch schemas schema, Has td schema ('Typedef ty))
1130+ => QualifiedAlias sch td
1131+ -- ^ name of the user defined type
1132+ -> Definition schemas (Alter sch (Drop td schema) schemas)
1133+dropType tydef = UnsafeDefinition $ "DROP" <+> "TYPE" <+> renderSQL tydef <> ";"
1134+
1135+-- | `ColumnTypeExpression`s are used in `createTable` commands.
1136+newtype ColumnTypeExpression (schemas :: SchemasType) (ty :: ColumnType)
1137+ = UnsafeColumnTypeExpression { renderColumnTypeExpression :: ByteString }
1138+ deriving (GHC.Generic,Show,Eq,Ord,NFData)
1139+instance RenderSQL (ColumnTypeExpression schemas ty) where
1140+ renderSQL = renderColumnTypeExpression
1141+
1142+-- | used in `createTable` commands as a column constraint to note that
1143+-- @NULL@ may be present in a column
1144+nullable
1145+ :: TypeExpression schemas (nullity ty)
1146+ -> ColumnTypeExpression schemas ('NoDef :=> 'Null ty)
1147+nullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NULL"
1148+
1149+-- | used in `createTable` commands as a column constraint to ensure
1150+-- @NULL@ is not present in a column
1151+notNullable
1152+ :: TypeExpression schemas (nullity ty)
1153+ -> ColumnTypeExpression schemas ('NoDef :=> 'NotNull ty)
1154+notNullable ty = UnsafeColumnTypeExpression $ renderSQL ty <+> "NOT NULL"
1155+
1156+-- | used in `createTable` commands as a column constraint to give a default
1157+default_
1158+ :: Expression '[] '[] 'Ungrouped schemas '[] '[] ty
1159+ -> ColumnTypeExpression schemas ('NoDef :=> ty)
1160+ -> ColumnTypeExpression schemas ('Def :=> ty)
1161+default_ x ty = UnsafeColumnTypeExpression $
1162+ renderSQL ty <+> "DEFAULT" <+> renderExpression x
1163+
1164+-- | not a true type, but merely a notational convenience for creating
1165+-- unique identifier columns with type `PGint2`
1166+serial2, smallserial
1167+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint2)
1168+serial2 = UnsafeColumnTypeExpression "serial2"
1169+smallserial = UnsafeColumnTypeExpression "smallserial"
1170+-- | not a true type, but merely a notational convenience for creating
1171+-- unique identifier columns with type `PGint4`
1172+serial4, serial
1173+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint4)
1174+serial4 = UnsafeColumnTypeExpression "serial4"
1175+serial = UnsafeColumnTypeExpression "serial"
1176+-- | not a true type, but merely a notational convenience for creating
1177+-- unique identifier columns with type `PGint8`
1178+serial8, bigserial
1179+ :: ColumnTypeExpression schemas ('Def :=> 'NotNull 'PGint8)
1180+serial8 = UnsafeColumnTypeExpression "serial8"
1181+bigserial = UnsafeColumnTypeExpression "bigserial"