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  1. MariaDB Server
  2. MDEV-38876

Investigate conjunctive predicate reordering

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Details

    • New Feature
    • Status: Open (View Workflow)
    • Major
    • Resolution: Unresolved
    • 12.3
    • Optimizer
    • None

    Description

      Found when looking at TPC-H query 6

      Significant differences are observed here
      https://database-doctor.com/posts/tpch-q06
      when predicates below

      SELECT SUM(l_extendedprice * l_discount) AS revenue
      FROM tpch.lineitem
      WHERE l_shipdate >= '1994-01-01'
        AND l_shipdate < '1995-01-01'
        AND l_discount BETWEEN 0.03 AND 0.05
        AND l_quantity < 24
      

      are re-ordered, from most lowest selectivity to highest, meaning less of the expression is evaluated across the whole dataset.

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            Unassigned Unassigned
            Johnston Rex Johnston
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              Created:
              Updated:

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