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

Andrei Lepikhov <a.lepikhov@postgrespro.ru>

From: Andrei Lepikhov <a.lepikhov@postgrespro.ru>
To: Alexander Korotkov <aekorotkov@gmail.com>
Cc: jian he <jian.universality@gmail.com>, Alena Rybakina <a.rybakina@postgrespro.ru>, Robert Haas <robertmhaas@gmail.com>, pgsql-hackers@postgresql.org, Peter Geoghegan <pg@bowt.ie>, "Finnerty, Jim" <jfinnert@amazon.com>, Marcos Pegoraro <marcos@f10.com.br>, teodor@sigaev.ru, Tomas Vondra <tomas.vondra@enterprisedb.com>, Peter Eisentraut <peter@eisentraut.org>, Ranier Vilela <ranier.vf@gmail.com>
Date: 2024-03-15T05:05:02Z
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 14/3/2024 17:39, Alexander Korotkov wrote:
> Thank you, Andrei.  Looks like a very undesirable side effect.  Do you
> have any idea why it happens?  Partition pruning should work correctly
> for both transformed and non-transformed quals, why does
> transformation hurt it?
Now we have the v23-0001-* patch with all issues resolved. The last one 
which caused execution stage pruning was about necessity to evaluate 
SAOP expression right after transformation. In previous version the core 
executed it on transformed expressions.

 > As you can see this case is not related to partial indexes.  Just no
 > index selective for the whole query.  However, splitting scan by the
 > OR qual lets use a combination of two selective indexes.
Thanks for the case. I will try to resolve it.

-- 
regards,
Andrei Lepikhov
Postgres Professional