Class MergeJoinStrategy

  • Direct Known Subclasses:
    EnhancedSortMergeJoinStrategy, NestedLoopJoinStrategy

    public class MergeJoinStrategy
    extends JoinStrategy
    MergeJoinStrategy supports generalized Full, Left Outer, and Inner Joins (containing non-equi join criteria) as long as there is at least one equi-join criteria Additionally supports Semi and Anti-Semi Joins. These too allow for generalized non-equi join criteria. TODO: when there is no non-equi join criteria matching duplicates from the outer side can be output immediately TODO: semi joins should only output left tuples Support for Intersect and Except is controlled by the grouping flag, which changes comparisons to check for null equality.