Re: Asymmetric partition-wise JOIN

On 5/7/21 23:15, Zhihong Yu wrote:
> On Mon, Jul 5, 2021 at 2:57 AM Andrey Lepikhov
> <a.lepikhov@postgrespro.ru <mailto:a.lepikhov@postgrespro.ru>> wrote:
> +            * Can't imagine situation when join relation already
> exists. But in
> +            * the 'partition_join' regression test it happens.
> +            * It may be an indicator of possible problems.
>
> Should a log be added in the above case ?
I worked more on this case and found more serious mistake. During
population of additional paths on the existed RelOptInfo we can remove
some previously generated paths that pointed from a higher-level list of
subplans and it could cause to lost of subplan links. I prohibit such
situation (you can read comments in the new version of the patch).
Also, choosing of a cheapest path after appendrel creation was added.
Unstable tests were fixed.

--
regards,
Andrey Lepikhov
Postgres Professional