Database.Relational.Query.Derives

This module defines typed SQLs derived from type informations.

Query derivation

specifiedKey

Arguments

:: PersistableWidth p

=> Pi a p

Unique key proof object which record type is a and key type is p.

-> Relation () a

Relation to add restriction.

-> Relation p a

Result restricted Relation

Query restricted with specified key.

unique

Arguments

:: PersistableWidth p

=> Key Unique a p

Unique key proof object which record type is a and key type is p.

-> Relation () a

Relation to add restriction.

-> Relation p a

Result restricted Relation

Query restricted with specified unique key.

primary'

Arguments

:: PersistableWidth p

=> Key Primary a p

Primary key proof object which record type is a and key type is p.

-> Relation () a

Relation to add restriction.

-> Relation p a

Result restricted Relation

Query restricted with specified primary key.

primary

Arguments

:: HasConstraintKey Primary a p

=> Relation () a

Relation to add restriction.

-> Relation p a

Result restricted Relation

Query restricted with infered primary key.

Update derivation

updateByConstraintKey

Arguments

:: Table r

Table to update

-> Key c r p

Key with constraint c, record type r and columns type p

-> KeyUpdate p r

Result typed Update

Typed KeyUpdate using specified constraint key.

primaryUpdate

Arguments

:: HasConstraintKey Primary r p

=> Table r

Table to update

-> KeyUpdate p r

Result typed Update

Typed KeyUpdate using infered primary key.

updateValuesWithKey :: ToSql q r => Pi r p -> r -> [q]

Convert from Haskell type r into SQL value q list expected by update form like

UPDATE <table> SET c0 = ?, c1 = ?, ..., cn = ? WHERE key0 = ? AND key1 = ? AND key2 = ? ...

using derived RecordToSql proof object.

Derived objects from table

derivedUniqueRelation

Arguments

:: TableDerivable r

=> Key Unique r k

Unique key proof object which record type is a and key type is p.

-> Projection c k

Unique key value to specify.

-> UniqueRelation () c r

Result restricted Relation

UniqueRelation infered from table.