Re: Incorrect result of bitmap heap scan.

Matthias van de Meent <boekewurm+postgres@gmail.com>

From: Matthias van de Meent <boekewurm+postgres@gmail.com>

To:

Cc: Andres Freund <andres@anarazel.de>, Andrew Dunstan <andrew@dunslane.net>, Melanie Plageman <melanieplageman@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, Konstantin Knizhnik <knizhnik@garret.ru>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Alexander Kuzmenkov <akuzmenkov@timescale.com>, Tom Lane <tgl@sss.pgh.pa.us>

Date: 2025-01-07T17:46:44Z

Lists: pgsql-hackers

Attachments

v3-0001-Remove-BitmapScan-s-skip_fetch-optimization.patch (application/octet-stream) patch v3-0001
v3-0002-isolationtester-showing-broken-index-only-bitmap-.patch (application/octet-stream) patch v3-0002

Hi,

I've rebased my earlier patch to fix some minor conflicts with the
work done on bitmaps in December last year. I've also included Andres'
cursor-based isolation test as 0002; which now passes.

This should take care of cfbot's misidentification of which patch to
test, and thus get CFBot to succeed again.

The patches for the back-branches didn't need updating, as those
branches have not diverged enough for those patches to have gotten
stale. They're still available in my initial mail over at [0].

Kind regards,

Matthias van de Meent
Neon (https://neon.tech)

[0] https://www.postgresql.org/message-id/CAEze2Wg1Q4gWzm9RZ0yXydm23Mj3iScu8LA__Zz3JJEgpnoGPQ%40mail.gmail.com

Commits

Add test for HeapBitmapScan's broken skip_fetch optimization
- 24da5b239a4b 18.0 landed
Remove HeapBitmapScan's skip_fetch optimization
- 459e7bf8e2f8 18.0 landed
- b9ec8125d167 13.21 landed
- 4934d38759cd 14.18 landed
- 77d90d6d6334 15.13 landed
- 980727b84107 16.9 landed
- 78cb2466f752 17.5 landed
Allow bitmap scans to operate as index-only scans when possible.
- 7c70996ebf09 11.0 cited