Safe Haskell | None |
---|---|
Language | Haskell2010 |
Binary relational operations on Select
s, that is, operations
which take two Select
s as arguments and return a single Select
.
All the binary relational operations have the same type specializations. For example:
unionAll :: S.Select (Column a, Column b) -> S.Select (Column a, Column b) -> S.Select (Column a, Column b)
Assuming the makeAdaptorAndInstance
splice has been run for the product type Foo
:
unionAll :: S.Select (Foo (Column a) (Column b) (Column c)) -> S.Select (Foo (Column a) (Column b) (Column c)) -> S.Select (Foo (Column a) (Column b) (Column c))
Please note that by design there are no binary relational functions
of type S.SelectArr a b -> S.SelectArr a b -> S.SelectArr a b
. Such
functions would allow violation of SQL's scoping rules and lead to
invalid queries.
unionAll
is very close to being the <|>
operator of a
Control.Applicative.Alternative
instance but it fails to work
only because of the typeclass constraint it has.
Synopsis
- unionAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- union :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- intersectAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- intersect :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- exceptAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- except :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields
- unionAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
- unionExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
- intersectAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
- intersectExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
- exceptAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
- exceptExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields'
Binary operations
unionAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
union :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
The same as unionAll, except that it additionally removes any duplicate rows.
intersectAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
intersect :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
The same as intersectAll, except that it additionally removes any duplicate rows.
exceptAll :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
except :: Default Binaryspec fields fields => Select fields -> Select fields -> Select fields Source #
The same as exceptAll, except that it additionally removes any duplicate rows.
Explicit versions
unionAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #
unionExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #
intersectAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #
intersectExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #
exceptAllExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #
exceptExplicit :: Binaryspec fields fields' -> Select fields -> Select fields -> Select fields' Source #