Copyright	(c) Eitan Chatav 2019
Maintainer	[email protected]
Stability	experimental
Safe Haskell	None
Language	Haskell2010

Squeal.PostgreSQL.Definition.View

Contents

Create
Drop

Description

create and drop views

Synopsis

createView :: (Has sch db schema, KnownSymbol vw) => QualifiedAlias sch vw -> Query '[] '[] db '[] view -> Definition db (Alter sch (Create vw (View view) schema) db)
createOrReplaceView :: (Has sch db schema, KnownSymbol vw) => QualifiedAlias sch vw -> Query '[] '[] db '[] view -> Definition db (Alter sch (CreateOrReplace vw (View view) schema) db)
dropView :: (Has sch db schema, KnownSymbol vw) => QualifiedAlias sch vw -> Definition db (Alter sch (DropSchemum vw View schema) db)
dropViewIfExists :: (Has sch db schema, KnownSymbol vw) => QualifiedAlias sch vw -> Definition db (Alter sch (DropIfExists vw schema) db)

Create

createView Source #

Arguments

:: (Has sch db schema, KnownSymbol vw)
=> QualifiedAlias sch vw	the name of the view to add
-> Query '[] '[] db '[] view	query
-> Definition db (Alter sch (Create vw (View view) schema) db)

Create a view.

>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]
>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]
>>> :{
let
  definition :: Definition
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc"  ::: 'View BC]]
  definition =
    createView #bc (select_ (#b :* #c) (from (table #abc)))
in printSQL definition
:}
CREATE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";

createOrReplaceView Source #

Arguments

:: (Has sch db schema, KnownSymbol vw)
=> QualifiedAlias sch vw	the name of the view to add
-> Query '[] '[] db '[] view	query
-> Definition db (Alter sch (CreateOrReplace vw (View view) schema) db)

Create or replace a view.

>>> type ABC = '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4]
>>> type BC = '["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4]
>>> :{
let
  definition :: Definition
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC)]]
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> ABC), "bc"  ::: 'View BC]]
  definition =
    createOrReplaceView #bc (select_ (#b :* #c) (from (table #abc)))
in printSQL definition
:}
CREATE OR REPLACE VIEW "bc" AS SELECT "b" AS "b", "c" AS "c" FROM "abc" AS "abc";

Drop

dropView Source #

Arguments

:: (Has sch db schema, KnownSymbol vw)
=> QualifiedAlias sch vw	view to remove
-> Definition db (Alter sch (DropSchemum vw View schema) db)

Drop a view.

>>> :{
let
  definition :: Definition
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
     , "bc"  ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]
  definition = dropView #bc
in printSQL definition
:}
DROP VIEW "bc";

dropViewIfExists Source #

Arguments

:: (Has sch db schema, KnownSymbol vw)
=> QualifiedAlias sch vw	view to remove
-> Definition db (Alter sch (DropIfExists vw schema) db)

Drop a view if it exists.

>>> :{
let
  definition :: Definition
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])
     , "bc"  ::: 'View ('["b" ::: 'Null 'PGint4, "c" ::: 'Null 'PGint4])]]
    '[ "public" ::: '["abc" ::: 'Table ('[] :=> '["a" ::: 'NoDef :=> 'Null 'PGint4, "b" ::: 'NoDef :=> 'Null 'PGint4, "c" ::: 'NoDef :=> 'Null 'PGint4])]]
  definition = dropViewIfExists #bc
in printSQL definition
:}
DROP VIEW IF EXISTS "bc";