Re: Removing unneeded self joins

Konstantin Knizhnik <k.knizhnik@postgrespro.ru>

From: Konstantin Knizhnik <k.knizhnik@postgrespro.ru>

To: Andrey Lepikhov <a.lepikhov@postgrespro.ru>, Thomas Munro <thomas.munro@gmail.com>

Cc: David Rowley <david.rowley@2ndquadrant.com>, Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Arseny Sher <a.sher@postgrespro.ru>

Date: 2019-08-07T16:23:34Z

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 →

Remove GUC_NOT_IN_SAMPLE from enable_self_join_elimination
- 717d0e8dd945 18.0 landed
Put enable_self_join_elimination into postgresql.conf.sample
- c2d329260cd8 18.0 landed
Get rid of ojrelid local variable in remove_rel_from_query()
- e167191dc146 18.0 landed
Implement Self-Join Elimination
- fc069a3a6319 18.0 cited
Revert: Remove useless self-joins
- d1d286d83c0e 17.0 landed
Replace lateral references to removed rels in subqueries
- 466979ef031a 17.0 landed
Replace relids in lateral subquery parse tree during SJE
- 489072ab7a9e 17.0 landed
Forbid SJE with result relation
- 8c441c082797 17.0 landed
Fix misuse of RelOptInfo.unique_for_rels cache by SJE
- 30b4955a4668 17.0 landed
Replace the relid in some missing fields during SJE
- a7928a57b9f0 17.0 landed
Revert 56-bit relfilenode change and follow-up commits.
- a448e49bcbe4 16.0 cited
Stabilize timetz test across DST transitions.
- 4a071afbd056 14.0 cited
Speed up finding EquivalenceClasses for a given set of rels
- 3373c7155350 13.0 cited
Fix mark-and-restore-skipping test case to not be a self-join.
- 24d08f3c0a1f 12.0 landed

Attachments

0001-Remove-self-joins-v19.patch (text/x-patch) patch v19-0001


On 05.08.2019 14:24, Andrey Lepikhov wrote:
>
>
> On 02/08/2019 04:54, Thomas Munro wrote:
>> On Thu, Jun 27, 2019 at 6:42 PM Andrey Lepikhov
>> <a.lepikhov@postgrespro.ru> wrote:
>>> Version v.17 of the patch that fix the bug see in attachment.
>>
>> While moving this to the September CF, I noticed that it needs to be
>> updated for the recent pg_list.h API changes.
> The patch was updated:
> 1. Changes caused by pg_list.h API changes.
> 2. Fix the problem of joint clause_relids and required_relids changes 
> [1].
> 3. Add eclass mentions of removed relation into the kept relation 
> (field eclass_indexes was introduced by commit 3373c71553).
>
> [1] 
> https://www.postgresql.org/message-id/flat/5c21029d-81a2-c999-6744-6a898fcc9a19%40postgrespro.ru
>

One more bug is fixed in this patch: OR clauses were not correctly 
updated in case of self join removal.



-- 
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company