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  1. MariaDB Server
  2. MDEV-33892

Spider: query JOINing 2 tables on different servers has performance issues

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    Description

      JOIN of 2 tables that residing on different servers by one common field, such as 

      select count(1) from t1 l inner join t2 le on l.lot_num = le.lot_num;

      exhibit performance issue.
      It takes hours if t1 and t2 are on different servers. And a few minutes if tables are on the same server.

      Attachments

        1. ddl.txt
          23 kB
        2. explain_json_local.txt
          3 kB
        3. explain_json_remote.txt
          3 kB
        4. mdev_33892.cnf
          0.1 kB
        5. mdev_33892.test
          2 kB
        6. profile_local.txt
          2 kB
        7. profile_remote.txt
          2 kB

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            holyfoot Alexey Botchkov
            YK Yakov Kushnirsky
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            Dates

              Created:
              Updated:

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