On Tue, 18 Dec 2001, Tom Lane wrote:
> The ri_triggers code has a lot of places that open things NoLock,
> but it only looks into the relcache entry and doesn't try to scan
> the relation. Nonetheless that code bothers me; we could be using
> an obsolete relcache entry if someone has just committed an ALTER
> TABLE on the relation. Some of the cases may be safe because a lock
> is held higher up (eg, on the table from which the trigger was fired)
> but I doubt they all are.
Probably not, since it looks like that's being done for the other table of
the constraint (not the one on which the trigger was fired).