Uploaded image for project: 'MariaDB Server'
  1. MariaDB Server
  2. MDEV-4017

GET_LOCK() with negative timeouts has strange behavior

    XMLWordPrintable

    Details

    • Type: Bug
    • Status: Closed (View Workflow)
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 10.0.0, 5.5.28a, 5.3.11, 5.2.13, 5.1.66
    • Fix Version/s: 5.5.45, 10.0.21, 10.1.7
    • Component/s: OTHER
    • Labels:
    • Environment:
      5.5

      Description

      I know that passing a negative timeout to GET_LOCK() makes no sense. But if you do it by mistake (perhaps with dynamic sql) there are 2 cases:

      • If the number is high, it is like passing 0:

        MariaDB [(none)]> SELECT GET_LOCK('x', -100);
        +---------------------+
        | GET_LOCK('x', -100) |
        +---------------------+
        |                   0 |
        +---------------------+
        1 row in set (0.01 sec)

      • if number is very low, it considers it as a positive number (you will need to kill the query):

        SELECT GET_LOCK('x', -1500000000);

        In both cases, I get no errors or warnings.

        Attachments

          Issue Links

            Activity

              People

              Assignee:
              svoj Sergey Vojtovich
              Reporter:
              f_razzoli Federico Razzoli
              Votes:
              0 Vote for this issue
              Watchers:
              5 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: