If you get corrupted tables or if mysqld always fails after some update commands, you can test whether this bug is reproducible by doing the following:
Take down the MySQL daemon (with mysqladmin shutdown).
Make a backup of the tables (to guard against the very unlikely case that the repair does something bad).
            Check all tables with myisamchk -s
            database/*.MYI. Repair any wrong tables with
            myisamchk -r
            database/table.MYI.
          
Make a second backup of the tables.
Remove (or move away) any old log files from the MySQL data directory if you need more space.
            Start mysqld with
            --log-bin. See
            Abschnitt 5.12.3, „Die binäre Update-Logdatei“. If you want to find a query
            that crashes mysqld, you should use
            --log --log-bin.
          
            When you have gotten a crashed table, stop the
            mysqld server.
          
Restore the backup.
            Restart the mysqld server
            without
            --log-bin
          
            Re-execute the commands with mysqlbinlog
            update-log-file | mysql. The update log is saved
            in the MySQL database directory with the name
            hostname-bin.#.
          
            If the tables are corrupted again or you can get
            mysqld to die with the above command, you
            have found reproducible bug that should be easy to fix! FTP
            the tables and the binary log to
            ftp://ftp.mysql.com/pub/mysql/upload/ and
            report it in our bugs database using the instructions given
            in Abschnitt 1.8, „Wie man Bugs oder Probleme meldet“. (Please note that the
            /pub/mysql/upload/ FTP directory is not
            listable, so you'll not see what you've uploaded in your FTP
            client.) If you are a support customer, you can use the
            MySQL Customer Support Center
            https://support.mysql.com/ to alert the MySQL
            team about the problem and have it fixed as soon as
            possible.
          
        You can also use the script mysql_find_rows
        to just execute some of the update statements if you want to
        narrow down the problem.
      
Dies ist eine Übersetzung des MySQL-Referenzhandbuchs, das sich auf dev.mysql.com befindet. Das ursprüngliche Referenzhandbuch ist auf Englisch, und diese Übersetzung ist nicht notwendigerweise so aktuell wie die englische Ausgabe. Das vorliegende deutschsprachige Handbuch behandelt MySQL bis zur Version 5.1.

