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  1. Calcite
  2. CALCITE-3546

Improve EnumerableDefaults nested loop join

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    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 1.21.0
    • Fix Version/s: 1.22.0
    • Component/s: None

      Description

      The current implementation of EnumerableDefaults#nestedLoopJoin builds the complete join result in a list before returning it. As specified in a comment there, this is "easy, but hogs memory". Also, it is not very efficient if after the join there is a LIMIT.
      An alternative implementation of nested loop join can be proposed, based on iterating through the outer an inner enumerables, and returning the results step by step (something similar to EnumerableDefaults#correlateJoin).

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              • Assignee:
                rubenql Ruben Q L
                Reporter:
                rubenql Ruben Q L
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