Copyright	(c) Eitan Chatav 2019
Maintainer	eitan@morphism.tech
Stability	experimental
Safe Haskell	None
Language	Haskell2010

Squeal.PostgreSQL.Manipulation.Delete

Contents

Delete

Description

delete statements

Synopsis

deleteFrom :: (SListI row, Has sch db schema, Has tab0 schema ('Table table)) => Aliased (QualifiedAlias sch) (tab ::: tab0) -> UsingClause with db params from -> Condition 'Ungrouped '[] with db params ((tab ::: TableToRow table) ': from) -> ReturningClause with db params ((tab ::: TableToRow table) ': from) row -> Manipulation with db params row
deleteFrom_ :: (Has sch db schema, Has tab0 schema ('Table table)) => Aliased (QualifiedAlias sch) (tab ::: tab0) -> Condition 'Ungrouped '[] with db params '[tab ::: TableToRow table] -> Manipulation with db params '[]

Delete

deleteFrom Source #

Arguments

:: (SListI row, Has sch db schema, Has tab0 schema ('Table table))
=> Aliased (QualifiedAlias sch) (tab ::: tab0)	table to delete from
-> UsingClause with db params from
-> Condition 'Ungrouped '[] with db params ((tab ::: TableToRow table) ': from)	condition under which to delete a row
-> ReturningClause with db params ((tab ::: TableToRow table) ': from) row	results to return
-> Manipulation with db params row

Delete rows from a table.

>>> type Columns = '["col1" ::: 'Def :=> 'NotNull 'PGint4, "col2" ::: 'NoDef :=> 'NotNull 'PGint4]
>>> type Schema = '["tab1" ::: 'Table ('[] :=> Columns), "tab2" ::: 'Table ('[] :=> Columns)]
>>> :{
let
  manp :: Manipulation with (Public Schema) '[] '["col1" ::: 'NotNull 'PGint4, "col2" ::: 'NotNull 'PGint4]
  manp = deleteFrom #tab1 (Using (table #tab2)) (#tab1 ! #col1 .== #tab2 ! #col2) (Returning (#tab1 & DotStar))
in printSQL manp
:}
DELETE FROM "tab1" AS "tab1" USING "tab2" AS "tab2" WHERE ("tab1"."col1" = "tab2"."col2") RETURNING "tab1".*

deleteFrom_ Source #

Arguments

:: (Has sch db schema, Has tab0 schema ('Table table))
=> Aliased (QualifiedAlias sch) (tab ::: tab0)	table to delete from
-> Condition 'Ungrouped '[] with db params '[tab ::: TableToRow table]	condition under which to delete a row
-> Manipulation with db params '[]

Delete rows returning Nil.

>>> type Columns = '["col1" ::: 'Def :=> 'NotNull 'PGint4]
>>> type Schema = '["tab" ::: 'Table ('[] :=> Columns)]
>>> :{
let
  manp :: Manipulation with (Public Schema) '[ 'NotNull 'PGint4] '[]
  manp = deleteFrom_ (#tab `as` #t) (#t ! #col1 .== param @1)
in printSQL manp
:}
DELETE FROM "tab" AS "t" WHERE ("t"."col1" = ($1 :: int4))