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>

Cc: Marcos Pegoraro <marcos@f10.com.br>, teodor@sigaev.ru, Ranier Vilela <ranier.vf@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Peter Geoghegan <pg@bowt.ie>

Date: 2023-07-06T10:20:46Z

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

Attachments

delta.diff (text/plain) patch

On 6/7/2023 03:06, Alena Rybakina wrote:
>> I corrected this constant in the patch.
The patch don't apply cleanly: it contains some trailing spaces.

Also, quick glance into the code shows some weak points;
1. transformBoolExprOr should have input type BoolExpr.
2. You can avoid the switch operator at the beginning of the function, 
because you only need one option.
3. Stale comments: RestrictIinfos definitely not exists at this point.
4. I don't know, you really need to copy the expr or not, but it is 
better to do as late, as possible.
5. You assume, that leftop is non-constant and rightop - constant. Why?
6.I doubt about equivalence operator. Someone can invent a custom '=' 
operator with another semantics, than usual. May be better to check 
mergejoinability?
7. I don't know how to confidently identify constant expressions at this 
level. So, I guess, You can only merge here expressions like 
"F(X)=Const", not an 'F(X)=ConstExpression'.

See delta.diff with mentioned changes in attachment.

-- 
regards,
Andrey Lepikhov
Postgres Professional