On Thu, 2011-12-15 at 09:37 +0100, Adis Nezirovic wrote: > Wiki instructions for creating insert trigger for PostgreSQL are wrong > http://wiki.dovecot.org/Quota/Dict > > Calling INSERT on the table from within BEFORE INSERT trigger creates > cascading trigger.
Yes.. > Instead, one should return NEW record from the trigger, and it will be > inserted after trigger execution. But does this handle race conditions when a record is inserted/deleted while the trigger is being run? That's the reason this trigger is so complex. > BEGIN > IF NEW.messages = 0 THEN > RETURN NEW; > ELSE > NEW.messages = - NEW.messages; > RETURN NEW; > END IF; > EXCEPTION WHEN unique_violation THEN > -- someone just inserted the record, update it > END; I'd guess the unique_violation is never caught here, and instead the whole INSERT fails?
