Re: small exclusion constraints patch

Jeff Davis <pgsql@j-davis.com> writes:
> Currently, the check for exclusion constraints performs a sanity check
> that's slightly too strict -- it assumes that a tuple will conflict with
> itself. That is not always the case: the operator might be "<>", in
> which case it's perfectly valid for the search for conflicts to not find
> itself.

> This patch simply removes that sanity check, and leaves a comment in
> place.

I'm a bit uncomfortable with removing the sanity check; it seems like a
good thing to have, especially since this code hasn't even made it out
of beta yet.  AFAIK the "<>" case is purely hypothetical, because we
have no index opclasses supporting such an operator, no?  How about just
documenting that we'd need to remove the sanity check if we ever did add
support for such a case?
        regards, tom lane