Horton

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

Peter Geoghegan <pg@bowt.ie>

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From: Peter Geoghegan <pg@bowt.ie>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Alexander Korotkov <aekorotkov@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Alena Rybakina <a.rybakina@postgrespro.ru>, jian he <jian.universality@gmail.com>, Nikolay Shaplov <dhyan@nataraj.su>, pgsql-hackers@lists.postgresql.org, pgsql-hackers@postgresql.org, Marcos Pegoraro <marcos@f10.com.br>, teodor@sigaev.ru, Peter Eisentraut <peter@eisentraut.org>, Ranier Vilela <ranier.vf@gmail.com>, Andrei Lepikhov <lepihov@gmail.com>
Date: 2024-10-04T14:20:20Z
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,

On Fri, Oct 4, 2024 at 8:31 AM Robert Haas <robertmhaas@gmail.com> wrote:
> Personally, I don't think this particular limitation is a problem. I
> don't think it will be terribly frequent in practice, and it doesn't
> seem any weirder than any of the other things that happen as a result
> of small and large integer constants being differently typed.

While it's not enough of a problem to hold up the patch, the behavior
demonstrated by my test case does seem worse than what happens as a
result of mixing integer constants in other, comparable contexts. That
was the basis of my concern, really.

The existing IN() syntax somehow manages to produce a useful bigint[]
SAOP when I use the same mix of integer types/constants that were used
for my original test case from yesterday:

pg@regression:5432 =# explain (analyze,buffers) select * from tenk1
where four in (1, 2_147_483_648) order by four, ten limit 5;
┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│                                                              QUERY
PLAN                                                               │
├───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
│ Limit  (cost=0.29..1.73 rows=5 width=244) (actual time=0.009..0.010
rows=5 loops=1)                                                   │
│   Buffers: shared hit=4
                                                                 │
│   ->  Index Scan using tenk1_four_ten_idx on tenk1
(cost=0.29..721.25 rows=2500 width=244) (actual time=0.008..0.009
rows=5 loops=1) │
│         Index Cond: (four = ANY ('{1,2147483648}'::bigint[]))
                                                                 │
│         Index Searches: 1
                                                                 │
│         Buffers: shared hit=4
                                                                 │
│ Planning Time: 0.046 ms
                                                                 │
│ Execution Time: 0.017 ms
                                                                 │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
(8 rows)

-- 
Peter Geoghegan