"Thomas F.O'Connell" <tfo(at)sitening(dot)com> writes:
> UPDATE groups
> SET count1 = v_group_count1, count2 = v_group_count2, count3 =
>
> For instance, when run, this stored procedure could try to acquire a lock on
> users2_groups despite not directly referencing it.
Does the users2_groups contain a foreign key reference to the groups table? If
so then if you need to update the groups table regularly you'll want an index
on the referring column. Otherwise in order to check the constraint Postgres
needs to do a sequential scan of the referring table to make sure your update
doesn't break a reference.
I don't know how this plays with locks though.
--
greg