Re: [bug?] Missed parallel safety checks, and wrong parallel safety

On Thu, Jun 17, 2021 at 4:54 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
> I have responded about heavy-weight locking stuff in my next email [1]
> and why I think the approach I mentioned will work. I don't deny that
> I might be missing something here.
>
> [1] - https://www.postgresql.org/message-id/CAA4eK1%2BT2CWqp40YqYttDA1Skk7wK6yDrkCD5GZ80QGr5ze-6g%40mail.gmail.com

I mean I saw that but I don't see how it addresses the visibility
issue. There could be a relation that is not visible to your snapshot
and upon which AccessExclusiveLock is held which needs to be
invalidated. You can't lock it because it's AccessExclusiveLock'd
already.

-- 
Robert Haas
EDB: http://www.enterprisedb.com