Re: Hash table scans outside transactions

On Wed, May 21, 2025 at 3:02 AM Aidar Imamov <a(dot)imamov(at)postgrespro(dot)ru> wrote:
>
> Hi!
> I tried to resend this thread directly to myself, but for some reason it
> ended up in the whole hackers list..
>
> I thought I'd chime in on this topic since it hasn't really been
> discussed
> anywhere else (or maybe I missed it).
> I've attached two patches: the first one is a little test extension to
> demonstrate the problem (just add "hash_test" to
> "shared_preload_libraries"),
> and the second is a possible solution. Basically, the idea is that we
> don't
> reset the scan counter if we find scans that started outside of the
> current
> transaction at the end. I have to admit, though, that I can't
> immediately
> say what other implications this might have or what else we need to
> watch
> out for if we try this.
> Maybe any thoughts on that?

I haven't reviewed the complete patch or tested it, but I don't see
any issues with it.

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com