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  1. Hive
  2. HIVE-562

join does not work well if there is a very large skew in keys

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Details

    • Improvement
    • Status: Open
    • Major
    • Resolution: Unresolved
    • 0.4.0
    • None
    • Query Processor
    • None

    Description

      Only the last table is streamed in case of regular joins.

      So, for any other table, or for any small table (in case of map-joins), if the number of values for a given key are very large, it does not scale.

      Attachments

        Issue Links

          depends upon

          Improvement - An improvement or enhancement to an existing feature or task. HIVE-965 optimize skewed joins

          • Major - Major loss of function.
          • Open

          Improvement - An improvement or enhancement to an existing feature or task. HIVE-963 no out of memory errors for skewed join

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. HIVE-964 handle skewed keys for a join in a separate job

          • Major - Major loss of function.
          • Closed

          Activity

            People

              Unassigned Unassigned
              namit Namit Jain
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              Dates

                Created:
                Updated: