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  1. MariaDB Server
  2. MDEV-21029

Incorrect result for expression with the <=> operator and IS NULL

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    Details

    • Type: Bug
    • Status: Confirmed (View Workflow)
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: 5.5, 10.0, 10.1, 10.2, 10.3, 10.4, 10.5
    • Fix Version/s: 10.2, 10.3, 10.4, 10.5
    • Component/s: None
    • Labels:
      None
    • Environment:
      Ubuntu 19.04

      Description

      Hi everyone,

      On the latest trunk version (0308de9), I could observe a bug, as demonstrated by the following test case:

      CREATE TABLE t0(c0 INT);
      		 
      INSERT INTO t0 VALUES (1);
      		 
      SELECT (c0 > (NULL <=> 0)) IS NULL FROM t0; -- expected: 0, actual: 1

      The expression seems to work correctly when it is used in a WHERE condition:

      SELECT * FROM t0 WHERE (c0 > (NULL <=> 0)) IS NULL; -- no row is fetched

        Attachments

          Issue Links

          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-21034 GREATEST() and LEAST() malfunction for NULL

          • Major - Major loss of function.
          • Confirmed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-21065 UNIQUE constraint causes a query with string comparison to omit a row in the result set

          • Major - Major loss of function.
          • Closed

            Activity

              People

              Assignee:
              igor Igor Babaev
              Reporter:
              mrigger Manuel Rigger
              Votes:
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              Watchers:
              3 Start watching this issue

                Dates

                Created:
                Updated:

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