An error occurred fetching the project authors.
  1. 21 Jan, 2008 1 commit
  2. 15 Nov, 2007 1 commit
    • istruewing@stella.local's avatar
      Bug#26379 - Combination of FLUSH TABLE and REPAIR TABLE · 06052741
      istruewing@stella.local authored
                  corrupts a MERGE table
      Bug 26867 - LOCK TABLES + REPAIR + merge table result in
                  memory/cpu hogging
      Bug 26377 - Deadlock with MERGE and FLUSH TABLE
      Bug 25038 - Waiting TRUNCATE
      Bug 25700 - merge base tables get corrupted by
                  optimize/analyze/repair table
      Bug 30275 - Merge tables: flush tables or unlock tables
                  causes server to crash
      Bug 19627 - temporary merge table locking
      Bug 27660 - Falcon: merge table possible
      Bug 30273 - merge tables: Can't lock file (errno: 155)
      
      The problems were:
      
      Bug 26379 - Combination of FLUSH TABLE and REPAIR TABLE
                      corrupts a MERGE table
      
        1. A thread trying to lock a MERGE table performs busy waiting while
           REPAIR TABLE or a similar table administration task is ongoing on
           one or more of its MyISAM tables.
        
        2. A thread trying to lock a MERGE table performs busy waiting until all
           threads that did REPAIR TABLE or similar table administration tasks
           on one or more of its MyISAM tables in LOCK TABLES segments do UNLOCK
           TABLES. The difference against problem #1 is that the busy waiting
           takes place *after* the administration task. It is terminated by
           UNLOCK TABLES only.
        
        3. Two FLUSH TABLES within a LOCK TABLES segment can invalidate the
           lock. This does *not* require a MERGE table. The first FLUSH TABLES
           can be replaced by any statement that requires other threads to
           reopen the table. In 5.0 and 5.1 a single FLUSH TABLES can provoke
           the problem.
      
      Bug 26867 - LOCK TABLES + REPAIR + merge table result in
                  memory/cpu hogging
      
        Trying DML on a MERGE table, which has a child locked and
        repaired by another thread, made an infinite loop in the server.
      
      Bug 26377 - Deadlock with MERGE and FLUSH TABLE
      
        Locking a MERGE table and its children in parent-child order
        and flushing the child deadlocked the server.
      
      Bug 25038 - Waiting TRUNCATE
      
        Truncating a MERGE child, while the MERGE table was in use,
        let the truncate fail instead of waiting for the table to
        become free.
      
      Bug 25700 - merge base tables get corrupted by
                  optimize/analyze/repair table
      
        Repairing a child of an open MERGE table corrupted the child.
        It was necessary to FLUSH the child first.
      
      Bug 30275 - Merge tables: flush tables or unlock tables
                  causes server to crash
      
        Flushing and optimizing locked MERGE children crashed the server.
      
      Bug 19627 - temporary merge table locking
      
        Use of a temporary MERGE table with non-temporary children
        could corrupt the children.
      
        Temporary tables are never locked. So we do now prohibit
        non-temporary chidlren of a temporary MERGE table.
      
      Bug 27660 - Falcon: merge table possible
      
        It was possible to create a MERGE table with non-MyISAM children.
      
      Bug 30273 - merge tables: Can't lock file (errno: 155)
      
        This was a Windows-only bug. Table administration statements
        sometimes failed with "Can't lock file (errno: 155)".
      
      These bugs are fixed by a new implementation of MERGE table open.
      
      When opening a MERGE table in open_tables() we do now add the
      child tables to the list of tables to be opened by open_tables()
      (the "query_list"). The children are not opened in the handler at
      this stage.
      
      After opening the parent, open_tables() opens each child from the
      now extended query_list. When the last child is opened, we remove
      the children from the query_list again and attach the children to
      the parent. This behaves similar to the old open. However it does
      not open the MyISAM tables directly, but grabs them from the already
      open children.
      
      When closing a MERGE table in close_thread_table() we detach the
      children only. Closing of the children is done implicitly because
      they are in thd->open_tables.
      
      For more detail see the comment at the top of ha_myisammrg.cc.
      
      Changed from open_ltable() to open_and_lock_tables() in all places
      that can be relevant for MERGE tables. The latter can handle tables
      added to the list on the fly. When open_ltable() was used in a loop
      over a list of tables, the list must be temporarily terminated
      after every table for open_and_lock_tables().
      table_list->required_type is set to FRMTYPE_TABLE to avoid open of
      special tables. Handling of derived tables is suppressed.
      These details are handled by the new function
      open_n_lock_single_table(), which has nearly the same signature as
      open_ltable() and can replace it in most cases.
      
      In reopen_tables() some of the tables open by a thread can be
      closed and reopened. When a MERGE child is affected, the parent
      must be closed and reopened too. Closing of the parent is forced
      before the first child is closed. Reopen happens in the order of
      thd->open_tables. MERGE parents do not attach their children
      automatically at open. This is done after all tables are reopened.
      So all children are open when attaching them.
      
      Special lock handling like mysql_lock_abort() or mysql_lock_remove()
      needs to be suppressed for MERGE children or forwarded to the parent.
      This depends on the situation. In loops over all open tables one
      suppresses child lock handling. When a single table is touched,
      forwarding is done.
      
      Behavioral changes:
      ===================
      
      This patch changes the behavior of temporary MERGE tables.
      Temporary MERGE must have temporary children.
      The old behavior was wrong. A temporary table is not locked. Hence
      even non-temporary children were not locked. See
      Bug 19627 - temporary merge table locking.
      
      You cannot change the union list of a non-temporary MERGE table
      when LOCK TABLES is in effect. The following does *not* work:
      CREATE TABLE m1 ... ENGINE=MRG_MYISAM ...;
      LOCK TABLES t1 WRITE, t2 WRITE, m1 WRITE;
      ALTER TABLE m1 ... UNION=(t1,t2) ...;
      However, you can do this with a temporary MERGE table.
      
      You cannot create a MERGE table with CREATE ... SELECT, neither
      as a temporary MERGE table, nor as a non-temporary MERGE table.
      CREATE TABLE m1 ... ENGINE=MRG_MYISAM ... SELECT ...;
      Gives error message: table is not BASE TABLE.
      06052741
  3. 31 May, 2007 1 commit
  4. 30 Mar, 2007 1 commit
  5. 24 Jul, 2006 2 commits
  6. 24 Feb, 2006 1 commit
  7. 22 Dec, 2005 1 commit
  8. 02 Dec, 2005 1 commit
  9. 28 Jul, 2005 1 commit
  10. 26 Apr, 2005 1 commit
  11. 25 Mar, 2005 1 commit
  12. 23 Mar, 2005 1 commit
  13. 26 Jan, 2005 1 commit
  14. 09 Dec, 2004 1 commit
  15. 30 Nov, 2004 1 commit
  16. 21 Sep, 2004 1 commit
  17. 25 May, 2004 1 commit
  18. 22 Jan, 2004 1 commit
  19. 10 Dec, 2003 1 commit
  20. 30 Oct, 2003 1 commit
  21. 16 Sep, 2003 1 commit
  22. 25 Jul, 2003 1 commit
  23. 26 Jun, 2003 1 commit
  24. 13 Mar, 2003 1 commit
  25. 11 Mar, 2003 1 commit
  26. 07 Mar, 2003 1 commit
  27. 05 Jan, 2003 1 commit
  28. 13 Dec, 2002 1 commit
  29. 04 Dec, 2002 1 commit
  30. 15 Oct, 2002 1 commit
  31. 12 Oct, 2002 1 commit
    • pem@mysql.com's avatar
      Task 430: Allowing braces in joins by simply removing them. · 8bd61c3f
      pem@mysql.com authored
      This is a simple fix, allowing a join_table_list in the right reduction of a
      normal_join sequence, instead of just a join_table. This makes things like
      "t1, (t2 left join t3)" work, but it also allows "join" and "cross join" instead
      of ",".
      
      This should fix the bug reported as:
        Subject: ODBC SQL syntax issue 
        From: Ivan Vazharov 
        Date: Mon, 30 Sep 2002 12:02:42 +0200 
      8bd61c3f
  32. 11 Oct, 2002 1 commit
  33. 03 Sep, 2002 1 commit
    • monty@mashka.mysql.fi's avatar
      Some trivial optimzations · a01a0840
      monty@mashka.mysql.fi authored
      Check if AND/OR expression can be NULL; Fixed bug in GROUP BY and-or-expression where expression could be NULL
      Bug fix for SHOW OPEN TABLES when user didn't have privilege to access all open tables.
      Better fix for ALTER TABLE on BDB tables.
      a01a0840
  34. 17 Aug, 2002 1 commit
  35. 16 Aug, 2002 1 commit
  36. 15 Jun, 2002 1 commit
  37. 17 Dec, 2001 1 commit
  38. 03 Jun, 2001 1 commit
  39. 21 Mar, 2001 1 commit