squeal-postgresql-0.6.0.0: Squeal PostgreSQL Library

Copyright(c) Eitan Chatav 2019
Maintainereitan@morphism.tech
Stabilityexperimental
Safe HaskellNone
LanguageHaskell2010

Squeal.PostgreSQL.Definition.View

Contents

Description

create and drop views

Synopsis

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";