On 30/10/2023 14:55, Richard Guo wrote:
On Thu, Oct 26, 2023 at 12:07 PM Andrei Lepikhov <a.lepik...@postgrespro.ru <mailto:a.lepik...@postgrespro.ru>> wrote:Do you've thought about the case, fixed with the commit 1db5667? As I see, that bugfix still isn't covered by regression tests. Could your approach of a PARAM_EXEC slot reusing break that case? Hm, I don't think so. The issue fixed by commit 1db5667 was caused by sharing PARAM_EXEC slots between different levels of NestLoop. AFAICS it's safe to share PARAM_EXEC slots within the same level of NestLoop. The change here is about sharing PARAM_EXEC slots between subquery's subplan_params and outer-relation variables, which happens within the same level of NestLoop. ... Did you notice a case that the change here breaks? Hi Tom, could you share your insights on this issue and the proposed fix?
I think your patch works correctly so far. I mentioned the commit 1db5667 because, as I see, the origin of the problem was parallel workers. I have thought about pushing Memoize down to a parallel worker and couldn't imagine whether such a solution would be correct.
Sorry if I disturbed you in vain. -- regards, Andrei Lepikhov Postgres Professional
