Opaleye.Join

Documentation

leftJoin :: (Default Unpackspec columnsA columnsA, Default Unpackspec columnsB columnsB, Default NullMaker columnsB nullableColumnsB) => Query columnsA -> Query columnsB -> ((columnsA, columnsB) -> Column PGBool) -> Query (columnsA, nullableColumnsB)

Example specialization:

leftJoin :: Query (Column a, Column b)
         -> Query (Column c, Column (Nullable d))
         -> (((Column a, Column b), (Column c, Column (Nullable d))) -> Column PGBool)
         -> Query ((Column a, Column b), (Column (Nullable c), Column (Nullable d)))

leftJoinExplicit :: Unpackspec columnsA columnsA -> Unpackspec columnsB columnsB -> NullMaker columnsB nullableColumnsB -> Query columnsA -> Query columnsB -> ((columnsA, columnsB) -> Column PGBool) -> Query (columnsA, nullableColumnsB)