On Thu, Apr 22, 2010 at 11:47:34AM +0930, Samuel Stearns wrote: > Howdy, > > I'm running in an 8.3.3 environment. What could cause, or how can I > diagnose, why an 'ALTER TABLE <name> ADD COLUMN' statement runs for hours > eventually locking users out and requiring to be killed in the end? >
ALTER TABLE commands require an exclusive lock on the table. I'm guessing you've got a long-running transaction ahead of the ALTER TABLE. take a look at pg_stat_activity, in particular 'waiting' and pg_locks. Ross -- Ross Reedstrom, Ph.D. [email protected] Systems Engineer & Admin, Research Scientist phone: 713-348-6166 The Connexions Project http://cnx.org fax: 713-348-3665 Rice University MS-375, Houston, TX 77005 GPG Key fingerprint = F023 82C8 9B0E 2CC6 0D8E F888 D3AE 810E 88F0 BEDE -- Sent via pgsql-admin mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
