Squeal.PostgreSQL.Expression.Sort

Sort expressions

Documentation

data SortExpression outer commons grp schemas params from where

SortExpressions are used by orderBy to optionally sort the results of a Query. Asc or Desc set the sort direction of a NotNull result column to ascending or descending. Ascending order puts smaller values first, where "smaller" is defined in terms of the .< operator. Similarly, descending order is determined with the .> operator. AscNullsFirst, AscNullsLast, DescNullsFirst and DescNullsLast options are used to determine whether nulls appear before or after non-null values in the sort ordering of a Null result column.

Constructors

Asc :: Expression outer commons grp schemas params from (NotNull ty) -> SortExpression outer commons grp schemas params from

Desc :: Expression outer commons grp schemas params from (NotNull ty) -> SortExpression outer commons grp schemas params from

AscNullsFirst :: Expression outer commons grp schemas params from (Null ty) -> SortExpression outer commons grp schemas params from

AscNullsLast :: Expression outer commons grp schemas params from (Null ty) -> SortExpression outer commons grp schemas params from

DescNullsFirst :: Expression outer commons grp schemas params from (Null ty) -> SortExpression outer commons grp schemas params from

DescNullsLast :: Expression outer commons grp schemas params from (Null ty) -> SortExpression outer commons grp schemas params from

Instances

Show (SortExpression outer commons grp schemas params from)

Defined in Squeal.PostgreSQL.Expression.Sort

Methods

showsPrec :: Int -> SortExpression outer commons grp schemas params from -> ShowS

show :: SortExpression outer commons grp schemas params from -> String

showList :: [SortExpression outer commons grp schemas params from] -> ShowS

RenderSQL (SortExpression outer commons grp schemas params from)

Defined in Squeal.PostgreSQL.Expression.Sort

Methods

renderSQL :: SortExpression outer commons grp schemas params from -> ByteString

class OrderBy expr where

The orderBy clause causes the result rows of a TableExpression to be sorted according to the specified SortExpression(s). If two rows are equal according to the leftmost expression, they are compared according to the next expression and so on. If they are equal according to all specified expressions, they are returned in an implementation-dependent order.

You can also control the order in which rows are processed by window functions using orderBy within Over.

Methods

orderBy :: [SortExpression outer commons grp schemas params from] -> expr outer commons grp schemas params from -> expr outer commons grp schemas params from

Instances

OrderBy WindowDefinition

Defined in Squeal.PostgreSQL.Expression.Window

Methods

orderBy :: [SortExpression outer commons grp schemas params from] -> WindowDefinition outer commons grp schemas params from -> WindowDefinition outer commons grp schemas params from

OrderBy TableExpression

Defined in Squeal.PostgreSQL.Query

Methods

orderBy :: [SortExpression outer commons grp schemas params from] -> TableExpression outer commons grp schemas params from -> TableExpression outer commons grp schemas params from