Re: Reducing memory consumed by RestrictInfo list translations in partitionwise join planning

amit <amitlangote09@gmail.com>

From: Amit Langote <amitlangote09@gmail.com>

To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>

Cc: David Rowley <dgrowleyml@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Dmitry Dolgov <9erthalion6@gmail.com>, tomas@vondra.me, vignesh C <vignesh21@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Richard Guo <guofenglinux@gmail.com>

Date: 2025-04-03T03:28:09Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Add assertion to verify derived clause has constant RHS
- 887160d1beae 18.0 landed
Make derived clause lookup in EquivalenceClass more efficient
- 88f55bc97622 18.0 landed
Doc: improve documentation for jsonpath behavior.
- 7014c9a4bba2 17.0 cited
Work around implementation restriction in adjust_appendrel_attrs.
- 767c598954bb 16.0 cited

Attachments

v9-0002-Make-derived-clause-lookup-in-EquivalenceClass-mo.patch (application/octet-stream) patch v9-0002
v9-0001-Add-assertion-to-verify-derived-clause-has-consta.patch (application/octet-stream) patch v9-0001

On Wed, Apr 2, 2025 at 9:52 PM Ashutosh Bapat
<ashutosh.bapat.oss@gmail.com> wrote:
> On Wed, Apr 2, 2025 at 1:00 PM Amit Langote <amitlangote09@gmail.com> wrote:
> > I'm feeling good about this version, but let me know if you have any
> > further thoughts / comments.
>
> Thanks for incorporating the changes and fixing initial hash table size.
>
> + #define EC_DERIVES_HASH_THRESHOLD 32
>
> Given that the constant is being used only at a single place, we don't
> need a macro. But I am not against the macro.

Yeah, let's keep it, because it documents well.

> PFA patch set with some minor edits in 0003. Also I have edited commit
> message of 0001 and 0002.
>
> In the commit messages of 0002,
> 1. mentioning that the lookup happens only for join clause generation
> is not accurate, since we lookup EM = constant clauses as well which
> are not join clauses.
> 2. In the second paragraph em1 and em2 are mentioned without
> mentioning what are they. I have rephrased it so as to avoid
> mentioning names of structure member.

Incorporated, thanks.

I'll plan to commit these tomorrow barring objections.

-- 
Thanks, Amit Langote