Re: pg_plan_advice

On Mon, Feb 9, 2026 at 10:55 AM Alexandra Wang
<alexandra(dot)wang(dot)oss(at)gmail(dot)com> wrote:
> On Sat, Feb 7, 2026 at 9:38 AM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> > Here is a new patch set (v14).
>
> Thanks for the patches! 0003 - 0005 look good to me.

I have committed those, as well as 0001 and 0002. Here's v15. The main
patch is now 0002, and has the following changes since the last
version:

- Added a new GUC pg_plan_advice.feedback_warnings, disabled by
default, which can be set to true to produce a warning about plan
advice strings that aren't fully working. (Previously, you had to use
EXPLAIN to get this information.)

- Use get_namespace_name_or_temp, rather than get_name_namespace,
consistently. One use of the latter function crept in, breaking
INDEX_SCAN and INDEX_ONLY_SCAN advice for temporary tables.

- Fix a problem in pgpa_scan.c that could cause spurious NO_GATHER
advice to be generated in certain situations, such as when joins were
proven empty.

- Fix a logic error in the handling of JOIN_ORDER advice that could
cause it to be marked as conflicting with PARTITIONWISE advice when
that was not in reality the case.

- Incorporate documentation corrections from David G. Johnston. I
didn't take all of his suggestions, but I took many of them, sometimes
with some additional wordsmithing on my part.

- Remove a stray comment.

Also a reminder that 0003 and 0004 (previously 0008 and 0009) don't
properly belong to this thread, but I've included them here because
otherwise the tests in the last patch don't pass. See
http://postgr.es/m/CA+TgmobRufbUSksBoxytGJS1P+mQY4rWctCk-d0iAUO6-k9Wrg@mail.gmail.com
for discussion of those patches.

--
Robert Haas
EDB: http://www.enterprisedb.com