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  1. MariaDB Server
  2. MDEV-21012

Very bad query optimization on DELETE with subquery

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    Details

    • Type: Task
    • Status: Open (View Workflow)
    • Priority: Major
    • Resolution: Unresolved
    • Fix Version/s: None
    • Component/s: Optimizer
    • Labels:
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      Description

      DELETEs using "WHERE ... IN (SELECT ...)" subquery syntax are much slower than DELETEs using the multi query delete syntax and a JOIN instead of a subquery.

      Original, still active, upstream report on the MySQL side is:

      https://bugs.mysql.com/bug.php?id=35794

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            Assignee:
            ralf.gebhardt@mariadb.com Ralf Gebhardt
            Reporter:
            hholzgra Hartmut Holzgraefe
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              Dates

              Created:
              Updated: