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

Andrei Lepikhov <a.lepikhov@postgrespro.ru>

From: Andrey Lepikhov <a.lepikhov@postgrespro.ru>
To: Alena Rybakina <lena.ribackina@yandex.ru>, Ranier Vilela <ranier.vf@gmail.com>
Cc: Marcos Pegoraro <marcos@f10.com.br>, teodor@sigaev.ru, PostgreSQL-development <pgsql-hackers@postgresql.org>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Peter Geoghegan <pg@bowt.ie>
Date: 2023-07-11T08:47:45Z
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 →
  1. Make group_similar_or_args() reorder clause list as little as possible

  2. Allow usage of match_orclause_to_indexcol() for joins

  3. Skip not SOAP-supported indexes while transforming an OR clause into SAOP

  4. Remove the wrong assertion from match_orclause_to_indexcol()

  5. Teach bitmap path generation about transforming OR-clauses to SAOP's

  6. Transform OR-clauses to SAOP's during index matching

  7. Fix the value of or_to_any_transform_limit in postgresql.conf.sample

  8. Transform OR clauses to ANY expression

  9. MergeAttributes code deduplication

  10. SEARCH and CYCLE clauses

  11. Improve estimation of OR clauses using extended statistics.

  12. Teach btree to handle ScalarArrayOpExpr quals natively.

  13. Revise collation derivation method and expression-tree representation.

  14. Instead of trying to force WHERE clauses into CNF or DNF normal form,

Attachments

On 10/7/2023 15:38, Alena Rybakina wrote:
> I agreed with the changes. Thank you for your work.
> 
> I updated patch and added you to the authors.
> 
> I specified Ranier Vilela as a reviewer.
This patch looks much better than earlier. But it definitely needs some 
covering with tests. As a first simple approximation, here you can see 
the result of regression tests, where the transformation limit is set to 
0. See in the attachment some test changes induced by these diffs.

Also, I see some impact of the transformation to other queries:
create_view.out:
(NOT x > z) ----> (x <= z)
inherit.out:
(((a)::text = 'ab'::text) OR ((a)::text = ANY ('{NULL,cd}'::text[])))
to
(((a)::text = ANY ('{NULL,cd}'::text[])) OR ((a)::text = 'ab'::text))

Transformations, mentioned above, are correct, of course. But it can be 
a sign of possible unstable behavior.

-- 
regards,
Andrey Lepikhov
Postgres Professional