Safe Haskell	None
Language	Haskell98

Opaleye.Operators

Description

Operators on Columns. Numeric Column types are instances of Num, so you can use *, /, +, - on them.

Synopsis

Documentation

restrict :: QueryArr (Column PGBool) () Source

Restrict query results to a particular condition. Corresponds to the guard method of the MonadPlus class. You would typically use restrict if you want to use Arrow notation.

keepWhen :: (a -> Column PGBool) -> QueryArr a a Source

Filter a QueryArr to only those rows where the given condition holds. This is the QueryArr equivalent of filter from the Prelude. You would typically use keepWhen if you want to use a "point free" style.

doubleOfInt :: Column PGInt4 -> Column PGFloat8 Source

(.==) :: Column a -> Column a -> Column PGBool infix 4 Source

(./=) :: Column a -> Column a -> Column PGBool infix 4 Source

(.===) :: Default EqPP columns columns => columns -> columns -> Column PGBool infix 4 Source

A polymorphic equality operator that works for all types that you have run makeAdaptorAndInstance on. This may be unified with .== in a future version.

(./==) :: Default EqPP columns columns => columns -> columns -> Column PGBool infix 4 Source

A polymorphic inequality operator that works for all types that you have run makeAdaptorAndInstance on. This may be unified with .== in a future version.

(.>) :: PGOrd a => Column a -> Column a -> Column PGBool infix 4 Source

(.<) :: PGOrd a => Column a -> Column a -> Column PGBool infix 4 Source

(.<=) :: PGOrd a => Column a -> Column a -> Column PGBool infix 4 Source

(.>=) :: PGOrd a => Column a -> Column a -> Column PGBool infix 4 Source

case_ :: [(Column PGBool, Column a)] -> Column a -> Column a Source

ifThenElse :: Column PGBool -> Column a -> Column a -> Column a Source

(.||) :: Column PGBool -> Column PGBool -> Column PGBool infixr 2 Source

not :: Column PGBool -> Column PGBool Source

(.++) :: Column PGText -> Column PGText -> Column PGText Source

lower :: Column PGText -> Column PGText Source

upper :: Column PGText -> Column PGText Source

like :: Column PGText -> Column PGText -> Column PGBool Source

ors :: Foldable f => f (Column PGBool) -> Column PGBool Source

True when any element of the container is true

in_ :: (Functor f, Foldable f) => f (Column a) -> Column a -> Column PGBool Source

(.&&) :: Column PGBool -> Column PGBool -> Column PGBool infixr 3 Source