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  1. Hive
  2. HIVE-26514

Use ItemSketches in Filter and Join selectivity estimates for Strings

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Details

    • Improvement
    • Status: Open
    • Major
    • Resolution: Unresolved
    • None
    • None
    • Hive, Logical Optimizer
    • None

    Description

      Introduce datasketches in the Filter and Join selectivity estimates. Right now  FilterSelectivityEstimator uses NDVs as its best guess to estimate selectivity for String columns with Equality and IN predicates.

      Attachments

        1. Frequent Item Sketches.pdf
          56 kB
          Soubhik Chakraborty

        Activity

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            soubhik.c Soubhik Chakraborty
            soubhik.c Soubhik Chakraborty
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            Dates

              Created:
              Updated: