Alvaro Herrera <alvherre@commandprompt.com> writes:
> Excerpts from Michael P. Soulier's message of mié jun 16 12:21:16 -0400 2010:
>> I'm trying to figure out why locking isn't working as I'm expecting. I have a
>> an operation wrapped in a transaction where I explicitely grab an exclusive
>> lock on my table. When another process concurrently runs to do the same, it
>> should block on attempting to acquire the exclusive lock, no?
>> 2010-06-16 12:14:31.913008500 LOG: statement: LOCK TABLE instances IN ROW
>> EXCLUSIVE MODE
> "row exclusive mode" does not block itself.
Specifically, see the table in
http://www.postgresql.org/docs/8.3/static/explicit-locking.html#LOCKING-TABLES
Exclusive lock modes are those that conflict with themselves; to wit,
SHARE ROW EXCLUSIVE mode or higher. The mode names are, um, historical.
regards, tom lane