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  1. Percona Server for MySQL
  2. PS-7019

Correct query results for LEFT JOIN with GROUP BY

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    Details

    • Type: Bug
    • Status: Done
    • Priority: High
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 8.0.20-11
    • Component/s: None
    • Labels:
      None

      Description

      This is a regression bug in MySQL 8.0.20, which changes behavior comparing to earlier 8.0 versions or 5.7.

      This report aims to help to avoid this regression in upcoming Percona Server release of the same version.

      I belive it is the same one as https://bugs.mysql.com/bug.php?id=99398

       

      There is a test case in upstream version, but below is how to reproduce with a little bit different case:

      – create two sandboxes to compare both

      dbdeployer deploy single 8.0.19
      dbdeployer deploy single 8.0.20

      – copy the .sh script to sandbox dir and .sql files to /tmp/

      – install mysql_random_data_load tool

      – run the test, the result should be different for GROUP BY query variant on both

      bash test_1.sh

       

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          1. 7019.tar.gz
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          2. PS-7019.diff
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              People

              Assignee:
              marcelo.altmann Marcelo Altmann
              Reporter:
              przemyslaw.malkowski@percona.com Przemyslaw Malkowski
              Votes:
              1 Vote for this issue
              Watchers:
              5 Start watching this issue

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                Resolved:

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