Re: POC, WIP: OR-clause support for indexes

Alena Rybakina <a.rybakina@postgrespro.ru>

From: Alena Rybakina <a.rybakina@postgrespro.ru>

To: Andrei Lepikhov <a.lepikhov@postgrespro.ru>, pgsql-hackers@postgresql.org

Cc: Peter Geoghegan <pg@bowt.ie>, Robert Haas <robertmhaas@gmail.com>, "Finnerty, Jim" <jfinnert@amazon.com>, Marcos Pegoraro <marcos@f10.com.br>, teodor@sigaev.ru, Ranier Vilela <ranier.vf@gmail.com>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Peter Eisentraut <peter@eisentraut.org>, Alexander Korotkov <aekorotkov@gmail.com>

Date: 2023-11-24T05:05:14Z

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 →

Make group_similar_or_args() reorder clause list as little as possible
- 775a06d44c04 18.0 landed
Allow usage of match_orclause_to_indexcol() for joins
- 627d63419e22 18.0 landed
Skip not SOAP-supported indexes while transforming an OR clause into SAOP
- 5bba0546eecb 18.0 landed
Remove the wrong assertion from match_orclause_to_indexcol()
- d4d11940df94 18.0 landed
Teach bitmap path generation about transforming OR-clauses to SAOP's
- ae4569161a27 18.0 landed
Transform OR-clauses to SAOP's during index matching
- d4378c0005e6 18.0 landed
Fix the value of or_to_any_transform_limit in postgresql.conf.sample
- 2af75e117478 17.0 landed
Transform OR clauses to ANY expression
- 72bd38cc99a1 17.0 landed
MergeAttributes code deduplication
- 64444ce071f6 17.0 cited
SEARCH and CYCLE clauses
- 3696a600e229 14.0 cited
Improve estimation of OR clauses using extended statistics.
- 25a9e54d2db3 14.0 cited
Teach btree to handle ScalarArrayOpExpr quals natively.
- 9e8da0f75731 9.2.0 cited
Revise collation derivation method and expression-tree representation.
- b310b6e31ce5 9.1.0 cited
Instead of trying to force WHERE clauses into CNF or DNF normal form,
- 9888192fb773 8.0.0 cited

On 23.11.2023 12:23, Andrei Lepikhov wrote:
> I think the usage of nodeToString for the generation of clause hash is 
> too expensive and buggy.
> Also, in the code, you didn't resolve hash collisions. So, I've 
> rewritten the patch a bit (see the attachment).
> One more thing: I propose to enable transformation by default at least 
> for quick detection of possible issues.
> This code changes tests in many places. But, as I see it, it mostly 
> demonstrates the positive effect of the transformation.

On 24.11.2023 06:30, Andrei Lepikhov wrote:

> On 23/11/2023 16:23, Andrei Lepikhov wrote:
>> This code changes tests in many places. But, as I see it, it mostly 
>> demonstrates the positive effect of the transformation.
>
> I found out that the postgres_fdw tests were impacted by the feature. 
> Fix it, because the patch is on the commitfest and passes buildfarm.
> Taking advantage of this, I suppressed the expression evaluation 
> procedure to make regression test changes more clear.

Thank you for your work. You are right, the patch with the current 
changes looks better and works more correctly.

To be honest, I didn't think we could use JumbleExpr in this way.

-- 
Regards,
Alena Rybakina
Postgres Professional