Re: Retiring is_pushed_down

vignesh C <vignesh21@gmail.com>

From: vignesh C <vignesh21@gmail.com>
To: Richard Guo <guofenglinux@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2024-01-21T12:37:47Z
Lists: pgsql-hackers
On Thu, 27 Jul 2023 at 08:25, Richard Guo <guofenglinux@gmail.com> wrote:
>
>
> On Tue, Jul 25, 2023 at 3:39 PM Richard Guo <guofenglinux@gmail.com> wrote:
>>
>> * This patch calculates the outer join relids that are being formed
>> generally in this way:
>>
>>     bms_difference(joinrelids, bms_union(outerrelids, innerrelids))
>>
>> Of course this can only be used after the outer join relids has been
>> added by add_outer_joins_to_relids().  This calculation is performed
>> multiple times during planning.  I'm not sure if this has performance
>> issues.  Maybe we can calculate it only once and store the result in
>> some place (such as in JoinPath)?
>
>
> In the v2 patch, I added a member in JoinPath to store the relid set of
> any outer joins that will be calculated at this join, and this would
> avoid repeating this calculation when creating nestloop/merge/hash join
> plan nodes.  Also fixed a comment in v2.

I'm seeing that there has been no activity in this thread for nearly 6
months, I'm planning to close this in the current commitfest unless
someone is planning to take it forward. It can be opened again when
there is more interest.

Regards,
Vignesh