Opaleye.Select

A Select represents an SQL SELECT statment. To run a Select use the functions in Opaleye.RunSelect. To create a Select you probably want to start by querying one of your Tables using selectTable. SelectArr is a parametrised version of Select, i.e. it can be passed arguments.

Documentation

type Select = SelectArr ()

A SELECT, i.e. an SQL query which produces a collection of rows.

Select a is analogous to a Haskell value [a].

data SelectArr a b

A parametrised Select. A SelectArr a b accepts an argument of type a.

SelectArr a b is analogous to a Haskell function a -> [b].

Instances

Arrow QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

arr :: (b -> c) -> QueryArr b c

first :: QueryArr b c -> QueryArr (b, d) (c, d)

second :: QueryArr b c -> QueryArr (d, b) (d, c)

(***) :: QueryArr b c -> QueryArr b' c' -> QueryArr (b, b') (c, c')

(&&&) :: QueryArr b c -> QueryArr b c' -> QueryArr b (c, c')

ArrowChoice QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

left :: QueryArr b c -> QueryArr (Either b d) (Either c d)

right :: QueryArr b c -> QueryArr (Either d b) (Either d c)

(+++) :: QueryArr b c -> QueryArr b' c' -> QueryArr (Either b b') (Either c c')

(|||) :: QueryArr b d -> QueryArr c d -> QueryArr (Either b c) d

ArrowApply QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

app :: QueryArr (QueryArr b c, b) c

Profunctor QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

dimap :: (a -> b) -> (c -> d) -> QueryArr b c -> QueryArr a d

lmap :: (a -> b) -> QueryArr b c -> QueryArr a c

rmap :: (b -> c) -> QueryArr a b -> QueryArr a c

(#.) :: forall a b c q. Coercible c b => q b c -> QueryArr a b -> QueryArr a c

(.#) :: forall a b c q. Coercible b a => QueryArr b c -> q a b -> QueryArr a c

ProductProfunctor QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

purePP :: b -> QueryArr a b

(****) :: QueryArr a (b -> c) -> QueryArr a b -> QueryArr a c

empty :: QueryArr () ()

(***!) :: QueryArr a b -> QueryArr a' b' -> QueryArr (a, a') (b, b')

Monad (QueryArr a)

Defined in Opaleye.Internal.QueryArr

Methods

(>>=) :: QueryArr a a0 -> (a0 -> QueryArr a b) -> QueryArr a b

(>>) :: QueryArr a a0 -> QueryArr a b -> QueryArr a b

return :: a0 -> QueryArr a a0

Functor (QueryArr a)

Defined in Opaleye.Internal.QueryArr

Methods

fmap :: (a0 -> b) -> QueryArr a a0 -> QueryArr a b

(<$) :: a0 -> QueryArr a b -> QueryArr a a0

Applicative (QueryArr a)

Defined in Opaleye.Internal.QueryArr

Methods

pure :: a0 -> QueryArr a a0

(<*>) :: QueryArr a (a0 -> b) -> QueryArr a a0 -> QueryArr a b

liftA2 :: (a0 -> b -> c) -> QueryArr a a0 -> QueryArr a b -> QueryArr a c

(*>) :: QueryArr a a0 -> QueryArr a b -> QueryArr a b

(<*) :: QueryArr a a0 -> QueryArr a b -> QueryArr a a0

Category QueryArr

Defined in Opaleye.Internal.QueryArr

Methods

id :: forall (a :: k). QueryArr a a

(.) :: forall (b :: k) (c :: k) (a :: k). QueryArr b c -> QueryArr a b -> QueryArr a c