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  1. Hive
  2. HIVE-1783

CommonJoinOperator optimize the case of 1:1 join

    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 0.7.0
    • Component/s: None
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      CommonJoinOperator.genObject() is expensive. It does a recursive and keeps lots of states because it has to:
      1. handle null cases for outer joins
      2. handle the case of duplicated keys from one join party
      We can do a minor optimization to detect a 1:1 join (which is quite common) before calling CommonJoinOperator.genObject() and forward columns in a simple for-loop if we are sure neither of 1 or 2 will happen.

        Attachments

        1. HIVE-1783.4.patch
          54 kB
          Siying Dong
        2. HIVE-1783.3.patch
          32 kB
          Siying Dong
        3. HIVE-1783.2.patch
          32 kB
          Siying Dong
        4. HIVE-1783.1.patch
          4 kB
          Siying Dong

          Activity

            People

            • Assignee:
              sdong Siying Dong
              Reporter:
              sdong Siying Dong
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              Dates

              • Created:
                Updated:
                Resolved: