Grouping algorithms

Grouping algorithms compute a summary of their input. They are applicable only if the query contains a GROUP BY clause, or if the query contains aggregate functions (such as SELECT COUNT(*) FROM T).

For more information, see HashGroupBy algorithm (GrByH), OrderedGroupBy algorithm (GrByO), and SingleRowGroupBy algorithm (GrByS).


HashGroupBy algorithm (GrByH)
ClusteredHashGroupBy algorithm (GrByHClust)
HashGroupBySets algorithm (GrByHSets)
OrderedGroupBy algorithm (GrByO)
OrderedGroupBySets algorithm (GrByOSets)
SingleRowGroupBy algorithm (GrByS)
SortedGroupBySets algorithm (GrBySSets)