Portability	unknown
Stability	experimental
Maintainer	[email protected]
Safe Haskell	None

Database.Relational.Query.Projectable

Contents

Conversion between individual Projections
Projectable from SQL strings
Projections of values
Placeholders
Projectable into SQL strings
Operators
Terms for Window function types
Zipping projections
Maybe type projecitoins
ProjectableFunctor and ProjectableApplicative

Description

This module defines operators on various polymorphic projections.

Synopsis

Conversion between individual Projections

expr :: Projection p a -> Expr p aSource

Project from Projection type into expression type.

Projectable from SQL strings

class SqlProjectable p whereSource

Interface to project SQL terms unsafely.

Methods

unsafeProjectSqlTerms Source

Arguments

:: [String]	SQL expression strings
-> p t	Result projection object

Unsafely project from SQL expression strings.

Instances

SqlProjectable (Expr p)	Unsafely make `Expr` from SQL terms.
SqlProjectable (Projection OverWindow)	Unsafely make `Projection` from SQL terms.
SqlProjectable (Projection Aggregated)	Unsafely make `Projection` from SQL terms.
SqlProjectable (Projection Flat)	Unsafely make `Projection` from SQL terms.

unsafeProjectSql :: SqlProjectable p => String -> p tSource

Unsafely Project single SQL term.

Projections of values

value :: (ShowConstantTermsSQL t, SqlProjectable p) => t -> p tSource

Generate polymorphic projection of SQL constant values from Haskell value.

valueTrue :: (SqlProjectable p, ProjectableMaybe p) => p (Maybe Bool)Source

Polymorphic proejction of SQL true value.

valueFalse :: (SqlProjectable p, ProjectableMaybe p) => p (Maybe Bool)Source

Polymorphic proejction of SQL false value.

values :: (ShowConstantTermsSQL t, SqlProjectable p) => [t] -> ListProjection p tSource

Polymorphic proejction of SQL set value from Haskell list.

unsafeValueNull :: SqlProjectable p => p (Maybe a)Source

Polymorphic projection of SQL null value.

Placeholders

data PlaceHolders p Source

Placeholder parameter type which has real parameter type arguemnt p.

Instances

ProjectableApplicative PlaceHolders	Compose record type `PlaceHolders` using applicative style.
ProjectableFunctor PlaceHolders	Compose seed of record type `PlaceHolders`.
ProjectableIdZip PlaceHolders	Zipping except for identity element laws against placeholder parameter type.
ProjectableMaybe PlaceHolders	Control phantom `Maybe` type in placeholder parameters.

addPlaceHolders :: Functor f => f a -> f (PlaceHolders p, a)Source

Unsafely add placeholder parameter to queries.

unsafePlaceHolders :: PlaceHolders pSource

Unsafely get placeholder parameter

placeholder' :: (PersistableWidth t, SqlProjectable p) => (p t -> a) -> (PlaceHolders t, a)Source

Provide scoped placeholder and return its parameter object.

placeholder :: (PersistableWidth t, SqlProjectable p, Monad m) => (p t -> m a) -> m (PlaceHolders t, a)Source

Provide scoped placeholder and return its parameter object. Monadic version.

Projectable into SQL strings

unsafeShowSqlExpr :: Expr p t -> String Source

Unsafely get SQL term from Expr.

unsafeShowSqlProjection :: Projection c r -> String Source

Unsafely get SQL term from Proejction.

class ProjectableShowSql p whereSource

Interface to get SQL term from projections.

Methods

unsafeShowSql Source

Arguments

:: p a	Source projection object
-> String	Result SQL expression string.

Unsafely generate SQL expression string from projection object.

Instances

ProjectableShowSql (Expr p)	Unsafely get SQL term from `Expr`.
ProjectableShowSql (Projection c)	Unsafely get SQL term from `Proejction`.

Operators

type SqlBinOp = Keyword -> Keyword -> Keyword Source

Binary operator type for SQL String.

unsafeBinOp :: (SqlProjectable p, ProjectableShowSql p) => SqlBinOp -> p a -> p b -> p cSource

Unsafely make projection binary operator from string binary operator.

unsafeUniOp :: (ProjectableShowSql p0, SqlProjectable p1) => (Keyword -> Keyword) -> p0 a -> p1 bSource

Unsafely make projection unary operator from SQL keyword.

(.=.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL = .

(.<.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL < .

(.<=.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL <= .

(.>.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL > .

(.>=.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL >= .

(.<>.) :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Compare operator corresponding SQL <> .

casesOrElse Source

Arguments

:: (SqlProjectable p, ProjectableShowSql p)
=> [(p (Maybe Bool), p a)]	Each when clauses
-> p a	Else result projection
-> p a	Result projection

Same as caseSearch, but you can write like list casesOrElse clause.

casesOrElse'Source

Arguments

:: (SqlProjectable p, ProjectableShowSql p)
=> (p a, [(p a, p b)])	Projection value to match and each when clauses list
-> p b	Else result projection
-> p b	Result projection

Uncurry version of case', and you can write like ... casesOrElse' clause.

caseSearch Source

Arguments

:: (SqlProjectable p, ProjectableShowSql p)
=> [(p (Maybe Bool), p a)]	Each when clauses
-> p a	Else result projection
-> p a	Result projection

Search case operator correnponding SQL search CASE. Like, CASE WHEN p0 THEN a WHEN p1 THEN b ... ELSE c END

caseSearchMaybe Source

Arguments

:: (ProjectableShowSql p, SqlProjectable p)
=> [(p (Maybe Bool), p (Maybe a))]	Each when clauses
-> p (Maybe a)	Result projection

Null default version of caseSearch.

case'Source

Arguments

:: (SqlProjectable p, ProjectableShowSql p)
=> p a	Projection value to match
-> [(p a, p b)]	Each when clauses
-> p b	Else result projection
-> p b	Result projection

Simple case operator correnponding SQL simple CASE. Like, CASE x WHEN v THEN a WHEN w THEN b ... ELSE c END

caseMaybe Source

Arguments

:: (SqlProjectable p, ProjectableShowSql p, ProjectableMaybe p)
=> p a	Projection value to match
-> [(p a, p (Maybe b))]	Each when clauses
-> p (Maybe b)	Result projection

Null default version of case'.

in' :: (SqlProjectable p, ProjectableShowSql p) => p t -> ListProjection p t -> p (Maybe Bool)Source

Binary operator corresponding SQL IN .

and' :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Logical operator corresponding SQL AND .

or' :: (SqlProjectable p, ProjectableShowSql p) => p ft -> p ft -> p (Maybe Bool)Source

Logical operator corresponding SQL OR .

isNothing :: (SqlProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)Source

Operator corresponding SQL IS NULL , and extended against record types.

isJust :: (SqlProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c (Maybe r) -> Projection c (Maybe Bool)Source

Operator corresponding SQL NOT (... IS NULL) , and extended against record type.

fromMaybe :: (SqlProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c r -> Projection c (Maybe r) -> Projection c rSource

Operator from maybe type using record extended isNull.

fromMaybe' :: (SqlProjectable (Projection c), ProjectableShowSql (Projection c), HasColumnConstraint NotNull r) => Projection c r -> Projection c (Maybe r) -> Projection c rSource

Deprecated: Use fromMaybe instead of this.

Deprecated. Operator from maybe type using record extended isNull.

not' :: (SqlProjectable p, ProjectableShowSql p) => p (Maybe Bool) -> p (Maybe Bool)Source

Logical operator corresponding SQL NOT .

exists :: (SqlProjectable p, ProjectableShowSql p) => ListProjection (Projection Exists) r -> p (Maybe Bool)Source

Logical operator corresponding SQL EXISTS .

(.||.) :: (SqlProjectable p, ProjectableShowSql p, IsString a) => p a -> p a -> p aSource

Concatinate operator corresponding SQL || .

(?||?) :: (SqlProjectable p, ProjectableShowSql p, IsString a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)Source

Concatinate operator corresponding SQL || . Maybe type version.

(.+.) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p aSource

Number operator corresponding SQL + .

(.-.) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p aSource

Number operator corresponding SQL - .

(./.) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p aSource

Number operator corresponding SQL / .

(.*.) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p a -> p a -> p aSource

Number operator corresponding SQL * .

negate' :: (SqlProjectable p, ProjectableShowSql p, Num a) => p a -> p aSource

Number negate uni-operator corresponding SQL -.

fromIntegral' :: (SqlProjectable p, ProjectableShowSql p, Integral a, Num b) => p a -> p bSource

Number fromIntegral uni-operator.

showNum :: (SqlProjectable p, ProjectableShowSql p, Num a, IsString b) => p a -> p bSource

Unsafely show number into string-like type in projections.

(?+?) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)Source

Number operator corresponding SQL + .

(?-?) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)Source

Number operator corresponding SQL - .

(?/?) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)Source

Number operator corresponding SQL / .

(?*?) :: (SqlProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a) -> p (Maybe a)Source

Number operator corresponding SQL * .

negateMaybe :: (SqlProjectable p, ProjectableShowSql p, Num a) => p (Maybe a) -> p (Maybe a)Source

Number negate uni-operator corresponding SQL -.

fromIntegralMaybe :: (SqlProjectable p, ProjectableShowSql p, Integral a, Num b) => p (Maybe a) -> p (Maybe b)Source

Number fromIntegral uni-operator.

showNumMaybe :: (SqlProjectable p, ProjectableShowSql p, Num a, IsString b) => p (Maybe a) -> p (Maybe b)Source

Unsafely show number into string-like type in projections.

Terms for Window function types

rank :: Projection OverWindow Int64 Source

RANK() term.

denseRank :: Projection OverWindow Int64 Source

DENSE_RANK() term.

rowNumber :: Projection OverWindow Int64 Source

ROW_NUMBER() term.

percentRank :: Projection OverWindow Double Source

PERCENT_RANK() term.

cumeDist :: Projection OverWindow Double Source

CUME_DIST() term.

dense_rank :: Projection OverWindow Int64 Source

Deprecated: Use denseRank instead of this.

DENSE_RANK() term.

row_number :: Projection OverWindow Int64 Source

Deprecated: Use rowNumber instead of this.

ROW_NUMBER() term.

percent_rank :: Projection OverWindow Double Source

Deprecated: Use percentRank instead of this.

PERCENT_RANK() term.

cume_dist :: Projection OverWindow Double Source

Deprecated: Use cumeDist instead of this.

CUME_DIST() term.

Zipping projections

projectZip :: ProjectableApplicative p => p a -> p b -> p (a, b)Source

Zipping projections.

(><) :: ProjectableApplicative p => p a -> p b -> p (a, b)Source

Binary operator the same as projectZip.

class ProjectableApplicative p => ProjectableIdZip p whereSource

Zipping except for identity element laws.

Methods

leftId :: p ((), a) -> p aSource

rightId :: p (a, ()) -> p aSource

Instances

ProjectableIdZip PlaceHolders

Zipping except for identity element laws against placeholder parameter type.

`Maybe` type projecitoins

class ProjectableMaybe p whereSource

Interface to control Maybe of phantom type in projections.

Methods

just :: p a -> p (Maybe a)Source

Cast projection phantom type into Maybe.

flattenMaybe :: p (Maybe (Maybe a)) -> p (Maybe a)Source

Compose nested Maybe phantom type on projection.

Instances

ProjectableMaybe PlaceHolders	Control phantom `Maybe` type in placeholder parameters.
ProjectableMaybe (Expr p)	Control phantom `Maybe` type in SQL expression type `Expr`.
ProjectableMaybe (Projection c)	Control phantom `Maybe` type in projection type `Projection`.

ProjectableFunctor and ProjectableApplicative

class ProjectableFunctor p whereSource

Weaken functor on projections.

Methods

(|$|) :: ProductConstructor (a -> b) => (a -> b) -> p a -> p bSource

Method like fmap.

Instances

ProjectableFunctor PlaceHolders	Compose seed of record type `PlaceHolders`.
ProjectableFunctor (Pi a)	Compose seed of projection path `Pi` which has record result type.
ProjectableFunctor (Projection c)	Compose seed of record type `Projection`.

class ProjectableFunctor p => ProjectableApplicative p whereSource

Weaken applicative functor on projections.

Methods

(|*|) :: p (a -> b) -> p a -> p bSource

Method like <*>.

Instances

ProjectableApplicative PlaceHolders	Compose record type `PlaceHolders` using applicative style.
ProjectableApplicative (Pi a)	Compose projection path `Pi` which has record result type using applicative style.
ProjectableApplicative (Projection c)	Compose record type `Projection` using applicative style.

ipfmap :: (ProjectableFunctor p, ProductConstructor (a -> b)) => p a -> p bSource

Same as |$| other than using infered record constructor.

Conversion between individual Projections

Projectable from SQL strings

Projections of values

Placeholders

Projectable into SQL strings

Operators

Terms for Window function types

Zipping projections

Maybe type projecitoins

ProjectableFunctor and ProjectableApplicative

`Maybe` type projecitoins