On 3/5/18, 7:08 PM, "Andres Freund" <andres@anarazel.de> wrote:
> On 2018-03-05 19:57:44 -0500, Tom Lane wrote:
>> Andres Freund <andres@anarazel.de> writes:
>>> One wrinkle in that plan is that it'd not be trivial to discern whether
>>> a lock couldn't be acquired or whether the object vanished. I don't
>>> really have good idea how to tackle that yet.
>> Do we really care which case applies?
>
> I think there might be cases where we do. As expand_vacuum_rel()
> wouldn't use missing_ok = true, it'd not be an issue for this specific
> callsite though.
I think it might be enough to simply note the ambiguity of returning
InvalidOid when skip-locked and missing-ok are both specified. Even
if RangeVarGetRelidExtended() did return whether skip-locked or
missing-ok applied, such a caller would likely not be able to trust
it anyway, as no lock would be held.
Nathan