List:Commits« Previous MessageNext Message »
From:Konstantin Osipov Date:July 23 2010 11:05am
Subject:Re: bzr commit into mysql-trunk-runtime branch (jon.hauglid:3084)
Bug#55498
View as plain text  
* Jon Olav Hauglid <jon.hauglid@stripped> [10/07/23 13:14]:
>  3084 Jon Olav Hauglid	2010-07-23
>       Bug #55498 SHOW CREATE TRIGGER takes wrong type of metadata lock
>       
>       The first problem was that SHOW CREATE TRIGGER took a stronger metadata
>       lock than required. This caused the statement to be blocked when it was
>       not needed. For example, LOCK TABLE WRITE in one connection would block
>       SHOW CREATE TRIGGER in another connection.
>       
>       Another problem was that a SHOW CREATE TRIGGER statement issued inside
>       a transaction did not release its metadata locks at the end of the
>       statement execution. This happened even if SHOW CREATE TRIGGER is an
>       information statement. The consequence was that SHOW CREATE TRIGGER
>       was able to block other connections from accessing the table
>       (e.g. using ALTER TABLE).
>       
>       This patch fixes the problem by changing SHOW CREATE TRIGGER to take
>       a MDL_SHARED_HIGH_PRIO metadata lock similar to what is already done
>       for SHOW CREATE TABLE. The patch also changes SHOW CREATE TRIGGER to
>       explicitly release any metadata locks taken by the statement after
>       it completes.

OK to push.

-- 
Thread
bzr commit into mysql-trunk-runtime branch (jon.hauglid:3084) Bug#55498Jon Olav Hauglid23 Jul
  • Re: bzr commit into mysql-trunk-runtime branch (jon.hauglid:3084)Bug#55498Konstantin Osipov23 Jul