"Simon Riggs" <[EMAIL PROTECTED]> writes: > As I've said elsewhere, we could have it lock each row, its just more > overhead if we do and not necessary at all for bulk data merging. > > I'll presume we want locking as an option, unless people say otherwise.
It's not so simple. If you look for a row to merge into and don't find one there's no row to lock. What unique constraints do is hold the lock on the index page where the entry would have to be added. That's the trick that plpgsql cannot implement. That's why users are forced to loop and retry until they manage to do an update successfully or insert successfully. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com Ask me about EnterpriseDB's Slony Replication support! -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
