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  1. Hive
  2. HIVE-7151

NULL keys should not be shuffled for inner equi joins

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Details

    • Bug
    • Status: Resolved
    • Major
    • Resolution: Duplicate
    • 0.14.0
    • None
    • Query Processor
    • None

    Description

      There is a huge skew in reducer load for NULL keys in shuffle joins, resulting in one slow reducer out of many.

      The NULL keys will not contribute towards the inner JOIN condition for equality (unless using null-safes).

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          is superceded by

          Bug - A problem which impairs or prevents the functions of the product. HIVE-7159 For inner joins push a 'is not null predicate' to the join sources for every non nullSafe join condition

          • Major - Major loss of function.
          • Closed

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              Unassigned Unassigned
              gopalv Gopal Vijayaraghavan
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                Created:
                Updated:
                Resolved: