Re: constraint exclusion and nulls in IN (..) clause

Emre Hasegeli <emre@hasegeli.com> writes:
> I am not sure if we are covering the case when clause_const and
> pred_const are both NULL.  In this case, we should be able to return
> true only by checking op_strict(pred_op) or maybe even without
> checking that.  Am I mistaken?

Yeah, that's there.  We need both operators to be strict, I think;
otherwise we can't really assume anything about what they'd return
for NULL inputs.  But if they are, we have NULL => NULL which is
valid for all proof cases.

            regards, tom lane