On Tue, Dec 28, 2010 at 8:55 AM, kakarukeys <kakaruk...@gmail.com> wrote:
> > > How long did you wait? > hours in the past. > For recent happenings, I aborted after 10 mins. > > Since it's a new table's creation, 'bbb' is empty. > The 'alter table' never finished, so the lock was not released. > aaa.id, bbb.topic_id are integers (id is auto-increament key) > That surely is a _long_ time for an empty table's ALTER. > > > I also saw this: > > http://postgresql.1045698.n5.nabble.com/Update-INSERT-RULE-while-running-for-Partitioning-td2057708.html > > "Note that using ALTER TABLE to add a constraint as well as > using DROP TABLE or TRUNCATE to remove/recycle partitions are > DDL commands that require exclusive locks. This will block > both readers and writers to the table(s) and can also cause readers > and writers to now interfere with each other. " > > In your case ALTER TABLE would lock bbb, but not aaa; other sessions should still be able to read aaa. Regards, -- gurjeet.singh @ EnterpriseDB - The Enterprise Postgres Company http://www.EnterpriseDB.com singh.gurj...@{ gmail | yahoo }.com Twitter/Skype: singh_gurjeet Mail sent from my BlackLaptop device
