Class RemoveRedundantTopN

  • All Implemented Interfaces:
    Rule<TopNNode>

    public class RemoveRedundantTopN
    extends Object
    implements Rule<TopNNode>
    Replace TopN node 1. With a Sort node when the subplan is guaranteed to produce fewer rows than N 2. With its source when the subplan produces only one row 3. With a empty ValuesNode when N is 0