Copyright	(c) Eitan Chatav 2019
Maintainer	eitan@morphism.tech
Stability	experimental
Safe Haskell	Safe-Inferred
Language	Haskell2010

Squeal.PostgreSQL.Session.Statement

Contents

Statement
Prepared

Description

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

Synopsis

data Statement db x y where
- Manipulation :: (All (OidOfNull db) params, SListI row) => EncodeParams db params x -> DecodeRow row y -> Manipulation '[] db params row -> Statement db x y
- Query :: (All (OidOfNull db) params, SListI row) => EncodeParams db params x -> DecodeRow row y -> Query '[] '[] db params row -> Statement db x y
query :: (GenericParams db params x xs, GenericRow row y ys) => Query '[] '[] db params row -> Statement db x y
manipulation :: (GenericParams db params x xs, GenericRow row y ys) => Manipulation '[] db params row -> Statement db x y
data Prepared m x y = Prepared {
- runPrepared :: x -> m y
- deallocate :: m ()
}

Statement

data Statement db x y where Source #

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

Instances details

Profunctor (Statement db) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement Methods renderSQL :: Statement db x y -> ByteString Source #

query Source #

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 Source #

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 Source #

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

Instances details

Monad m => Category (Prepared m :: Type -> Type -> Type) Source #
Instance details 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) Source #
Instance details 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 #
Monad m => Arrow (Prepared m) Source #
Instance details 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') #
Monad m => ArrowChoice (Prepared m) Source #
Instance details 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) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement Methods loop :: Prepared m (b, d) (c, d) -> Prepared m b c #
MonadPlus m => ArrowPlus (Prepared m) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement Methods (<+>) :: Prepared m b c -> Prepared m b c -> Prepared m b c #
MonadPlus m => ArrowZero (Prepared m) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement Methods zeroArrow :: Prepared m b c #
Monad m => Choice (Prepared m) Source #
Instance details 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) #
MonadFix m => Costrong (Prepared m) Source #
Instance details 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 #
Monad m => Strong (Prepared m) Source #
Instance details 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) #
Monad m => Traversing (Prepared m) Source #
Instance details 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 #
Functor m => Profunctor (Prepared m) Source #
Instance details 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 #
Alternative m => Alternative (Prepared m x) Source #
Instance details 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] #
Applicative m => Applicative (Prepared m x) Source #
Instance details 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 #
Functor m => Functor (Prepared m x) Source #
Instance details 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 #
Generic (Prepared m x y) Source #
Instance details 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) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement type Rep1 (Prepared m x :: Type -> Type) = D1 ('MetaData "Prepared" "Squeal.PostgreSQL.Session.Statement" "squeal-postgresql-0.9.1.3-FfCgbPNg57H53ZAGizr3Nu" 'False) (C1 ('MetaCons "Prepared" 'PrefixI 'True) (S1 ('MetaSel ('Just "runPrepared") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) ((FUN 'Many x :: TYPE LiftedRep -> Type) :.: Rec1 m) :*: S1 ('MetaSel ('Just "deallocate") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (m ()))))
type Rep (Prepared m x y) Source #
Instance details Defined in Squeal.PostgreSQL.Session.Statement type Rep (Prepared m x y) = D1 ('MetaData "Prepared" "Squeal.PostgreSQL.Session.Statement" "squeal-postgresql-0.9.1.3-FfCgbPNg57H53ZAGizr3Nu" '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 ()))))