Safe Haskell	None
Language	Haskell2010

PostgreSQL.Statement

Description

Tools to deal with templates and statements are defined here.

Synopsis

data Template a
code :: Text -> Template a
identifier :: Text -> Template a
string :: Text -> Template a
param :: forall b a. Param b => (a -> b) -> Template a
paramWith :: Info (a -> Value) -> Template a
constant :: forall b a. Param b => b -> Template a
data Statement a = Statement {
- statement_code :: ByteString
- statement_mkParams :: a -> [PackedParam]
- statement_types :: [Oid]
- statement_name :: ByteString
}
renderTemplate :: Template a -> Statement a
data PreparedStatement a = PreparedStatement {
- preparedStatement_name :: ByteString
- preparedStatement_mkParams :: a -> [PackedParamPrepared]
}
tpl :: QuasiQuoter
stmt :: QuasiQuoter

Documentation

data Template a Source #

SQL statement template

Since: 0.0.0

Instances

Instances details

Contravariant Template Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods contramap :: (a -> b) -> Template b -> Template a # (>$) :: b -> Template b -> Template a #
(HasField n r a, Param a) => IsLabel n (Template r) Source #	`OverloadedLabels` helper for `param` #myParam === param (getField @"myParam") Use this with a database: data MyFoo = MyFoo { bar :: Int, baz :: String } myStatementTpl :: Template MyFoo myStatementTpl = "SELECT * FROM my_foo WHERE bar = " <> #bar <> " AND baz = " <> #baz Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods fromLabel :: Template r #
IsString (Template a) Source #	`OverloadedStrings` helper for `code` "my code" === code "my code" Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods fromString :: String -> Template a #
Semigroup (Template a) Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods (<>) :: Template a -> Template a -> Template a # sconcat :: NonEmpty (Template a) -> Template a # stimes :: Integral b => b -> Template a -> Template a #
Monoid (Template a) Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods mempty :: Template a # mappend :: Template a -> Template a -> Template a # mconcat :: [Template a] -> Template a #

code :: Text -> Template a Source #

Create a code-only statement.

Since: 0.0.0

identifier :: Text -> Template a Source #

Create a code segment that mentions the given identifier (e.g. table or column name).

Since: 0.0.0

string :: Text -> Template a Source #

Encase the given string literal in single quotes. Single quotes in the literal are automatically escaped.

Since: 0.0.0

param :: forall b a. Param b => (a -> b) -> Template a Source #

Reference a parameter.

Since: 0.0.0

paramWith :: Info (a -> Value) -> Template a Source #

Reference a parameter.

Since: 0.0.0

constant :: forall b a. Param b => b -> Template a Source #

Constant part of a query.

Since: 0.0.0

data Statement a Source #

Rendered SQL statement

Since: 0.0.0

Constructors

Statement
Fields statement_code :: ByteString statement_mkParams :: a -> [PackedParam] statement_types :: [Oid] statement_name :: ByteString

Instances

Instances details

Contravariant Statement Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods contramap :: (a -> b) -> Statement b -> Statement a # (>$) :: b -> Statement b -> Statement a #
Executable Statement Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Query.Class Methods execute :: Query query => Statement param -> param -> query (NativeResult query) Source #

renderTemplate :: Template a -> Statement a Source #

Render the SQL statement.

Since: 0.0.0

data PreparedStatement a Source #

Prepared statement

Since: 0.0.0

Constructors

PreparedStatement
Fields preparedStatement_name :: ByteString preparedStatement_mkParams :: a -> [PackedParamPrepared]

Instances

Instances details

Contravariant PreparedStatement Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Statement Methods contramap :: (a -> b) -> PreparedStatement b -> PreparedStatement a # (>$) :: b -> PreparedStatement b -> PreparedStatement a #
Executable PreparedStatement Source #	Since: 0.0.0
Instance details Defined in PostgreSQL.Query.Class Methods execute :: Query query => PreparedStatement param -> param -> query (NativeResult query) Source #

tpl :: QuasiQuoter Source #

Produces a Template expression.

Supports the same features as stmt.

Since: 0.0.0

stmt :: QuasiQuoter Source #

Produces a Statement expression.

[stmt| SELECT $param * 2 |]

Use $$ to render a single $.

Parameters

Use $param or ${param} to reference a query parameter.

[stmt| ${x} |] is equivalent to param x.

Substitutions

Use $(substr) to embed another Template where substr :: Template a.

[stmt| $(x) |] is equivalent to x.

Examples

data MyParams = MyParams { foo :: Int, bar :: Text }

myStatement :: Statement MyParams
myStatement = [stmt| SELECT baz FROM my_table WHERE foo > ${foo} AND bar = ${bar} |]

Since: 0.0.0