Re: BUG #18692: Segmentation fault when extending a varchar column with a gist index with custom signal length

Alexander Korotkov <aekorotkov@gmail.com> writes:
> On Thu, Nov 7, 2024 at 8:47 AM Tender Wang <tndrwang@gmail.com> wrote:
>> Based on Tom's analysis, I  provide a POC patch. I'm not sure if it is right
>> to use DEFAULT_COLLATION_OID in the patch.

> Thank you.  But I'm not sure about DEFAULT_COLLATION_OID.

I don't quite trust that either.  But since we only care about
equality, wouldn't it be OK to use C_COLLATION_OID?

> Therefore, we can compare two text[] just with datumIsEqual().
> Attached patch implements this.

I think this is nonsense.  What about toasted datums, or even
just short-header ones?  The one coming from an on-disk tuple
is pretty likely to be short-header for plausible sizes of
the options, but the one we just constructed in memory will
not be.

            regards, tom lane