Squeal.PostgreSQL.Session.Statement

A top-level Statement type wraps a Query or Manipulation together with an EncodeParams and a DecodeRow.

Statement

data Statement db x y where

A Statement consists of a Manipulation or a Query that can be run in a MonadPQ.

Constructors

Manipulation

Constructor for a data manipulation language Statement

Fields

• :: (All (OidOfNull db) params, SListI row)
• => EncodeParams db params x

  encoding of parameters

• -> DecodeRow row y

  decoding of returned rows

• -> Manipulation '[] db params row

  insertInto, update, or deleteFrom, ...

• -> Statement db x y

Query

Constructor for a structured query language Statement

Fields

• :: (All (OidOfNull db) params, SListI row)
• => EncodeParams db params x

  encoding of parameters

• -> DecodeRow row y

  decoding of returned rows

• -> Query '[] '[] db params row

  select, values, ...

• -> Statement db x y

Instances

Profunctor (Statement db)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

dimap :: (a -> b) -> (c -> d) -> Statement db b c -> Statement db a d

lmap :: (a -> b) -> Statement db b c -> Statement db a c

rmap :: (b -> c) -> Statement db a b -> Statement db a c

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

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

Functor (Statement db x)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

fmap :: (a -> b) -> Statement db x a -> Statement db x b

(<$) :: a -> Statement db x b -> Statement db x a

RenderSQL (Statement db x y)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

renderSQL :: Statement db x y -> ByteString

query

Arguments

:: (GenericParams db params x xs, GenericRow row y ys)

=> Query '[] '[] db params row

select, values, ...

-> Statement db x y

Smart constructor for a structured query language Statement

manipulation

Arguments

:: (GenericParams db params x xs, GenericRow row y ys)

=> Manipulation '[] db params row

insertInto, update, or deleteFrom, ...

-> Statement db x y

Smart constructor for a data manipulation language Statement

Prepared

data Prepared m x y

prepare and prepare_ create a Prepared statement. A Prepared statement is a server-side object that can be used to optimize performance. When prepare or prepare_ is executed, the specified Statement is parsed, analyzed, and rewritten.

When the runPrepared command is subsequently issued, the Prepared statement is planned and executed. This division of labor avoids repetitive parse analysis work, while allowing the execution plan to depend on the specific parameter values supplied.

Prepared statements only last for the duration of the current database session. Prepared statements can be manually cleaned up using the deallocate command.

Constructors

Prepared

Fields

• runPrepared :: x -> m y

  execute a prepared statement

• deallocate :: m ()

  manually clean up a prepared statement

Instances

Monad m => Arrow (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

arr :: (b -> c) -> Prepared m b c

first :: Prepared m b c -> Prepared m (b, d) (c, d)

second :: Prepared m b c -> Prepared m (d, b) (d, c)

(***) :: Prepared m b c -> Prepared m b' c' -> Prepared m (b, b') (c, c')

(&&&) :: Prepared m b c -> Prepared m b c' -> Prepared m b (c, c')

MonadPlus m => ArrowZero (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

zeroArrow :: Prepared m b c

MonadPlus m => ArrowPlus (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

(<+>) :: Prepared m b c -> Prepared m b c -> Prepared m b c

Monad m => ArrowChoice (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

left :: Prepared m b c -> Prepared m (Either b d) (Either c d)

right :: Prepared m b c -> Prepared m (Either d b) (Either d c)

(+++) :: Prepared m b c -> Prepared m b' c' -> Prepared m (Either b b') (Either c c')

(|||) :: Prepared m b d -> Prepared m c d -> Prepared m (Either b c) d

MonadFix m => ArrowLoop (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

loop :: Prepared m (b, d) (c, d) -> Prepared m b c

Monad m => Traversing (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

traverse' :: Traversable f => Prepared m a b -> Prepared m (f a) (f b)

wander :: (forall (f :: Type -> Type). Applicative f => (a -> f b) -> s -> f t) -> Prepared m a b -> Prepared m s t

Monad m => Choice (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

left' :: Prepared m a b -> Prepared m (Either a c) (Either b c)

right' :: Prepared m a b -> Prepared m (Either c a) (Either c b)

Monad m => Strong (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

first' :: Prepared m a b -> Prepared m (a, c) (b, c)

second' :: Prepared m a b -> Prepared m (c, a) (c, b)

MonadFix m => Costrong (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

unfirst :: Prepared m (a, d) (b, d) -> Prepared m a b

unsecond :: Prepared m (d, a) (d, b) -> Prepared m a b

Functor m => Profunctor (Prepared m)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

dimap :: (a -> b) -> (c -> d) -> Prepared m b c -> Prepared m a d

lmap :: (a -> b) -> Prepared m b c -> Prepared m a c

rmap :: (b -> c) -> Prepared m a b -> Prepared m a c

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

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

Monad m => Category (Prepared m :: Type -> Type -> Type)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

id :: forall (a :: k). Prepared m a a

(.) :: forall (b :: k) (c :: k) (a :: k). Prepared m b c -> Prepared m a b -> Prepared m a c

Generic1 (Prepared m x :: Type -> Type)

Defined in Squeal.PostgreSQL.Session.Statement

Associated Types

type Rep1 (Prepared m x) :: k -> Type

Methods

from1 :: forall (a :: k). Prepared m x a -> Rep1 (Prepared m x) a

to1 :: forall (a :: k). Rep1 (Prepared m x) a -> Prepared m x a

Functor m => Functor (Prepared m x)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

fmap :: (a -> b) -> Prepared m x a -> Prepared m x b

(<$) :: a -> Prepared m x b -> Prepared m x a

Applicative m => Applicative (Prepared m x)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

pure :: a -> Prepared m x a

(<*>) :: Prepared m x (a -> b) -> Prepared m x a -> Prepared m x b

liftA2 :: (a -> b -> c) -> Prepared m x a -> Prepared m x b -> Prepared m x c

(*>) :: Prepared m x a -> Prepared m x b -> Prepared m x b

(<*) :: Prepared m x a -> Prepared m x b -> Prepared m x a

Alternative m => Alternative (Prepared m x)

Defined in Squeal.PostgreSQL.Session.Statement

Methods

empty :: Prepared m x a

(<|>) :: Prepared m x a -> Prepared m x a -> Prepared m x a

some :: Prepared m x a -> Prepared m x [a]

many :: Prepared m x a -> Prepared m x [a]

Generic (Prepared m x y)

Defined in Squeal.PostgreSQL.Session.Statement

Associated Types

type Rep (Prepared m x y) :: Type -> Type

Methods

from :: Prepared m x y -> Rep (Prepared m x y) x0

to :: Rep (Prepared m x y) x0 -> Prepared m x y

type Rep1 (Prepared m x :: Type -> Type)

Defined in Squeal.PostgreSQL.Session.Statement

type Rep1 (Prepared m x :: Type -> Type) = D1 ('MetaData "Prepared" "Squeal.PostgreSQL.Session.Statement" "squeal-postgresql-0.9.0.0-D17NIjlcsGRAwJTaCTXyvM" 'False) (C1 ('MetaCons "Prepared" 'PrefixI 'True) (S1 ('MetaSel ('Just "runPrepared") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (((->) x :: Type -> Type) :.: Rec1 m) :*: S1 ('MetaSel ('Just "deallocate") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (m ()))))

type Rep (Prepared m x y)

Defined in Squeal.PostgreSQL.Session.Statement

type Rep (Prepared m x y) = D1 ('MetaData "Prepared" "Squeal.PostgreSQL.Session.Statement" "squeal-postgresql-0.9.0.0-D17NIjlcsGRAwJTaCTXyvM" 'False) (C1 ('MetaCons "Prepared" 'PrefixI 'True) (S1 ('MetaSel ('Just "runPrepared") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (x -> m y)) :*: S1 ('MetaSel ('Just "deallocate") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (m ()))))