Horton

Re: Postgres 11 release notes

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Bruce Momjian <bruce@momjian.us>
Cc: Andres Freund <andres@anarazel.de>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Adrien Nayrat <adrien.nayrat@anayrat.info>
Date: 2018-08-26T11:23:05Z
Lists: pgsql-hackers 
On Sun, Aug 26, 2018 at 12:17 AM Bruce Momjian <bruce@momjian.us> wrote:
>
> On Sat, Aug 25, 2018 at 11:42:35AM -0700, Andres Freund wrote:
> >
> >
> > On August 25, 2018 11:41:11 AM PDT, Bruce Momjian <bruce@momjian.us> wrote:
> > >On Sun, Aug 12, 2018 at 11:21:26AM +0200, Adrien Nayrat wrote:
> > >> Hello,
> > >>
> > >> It seems this feature is missing in releases notes ?
> > >>
> > >> commit 1f6d515a67ec98194c23a5db25660856c9aab944
> > >> Author: Robert Haas <rhaas@postgresql.org>
> > >> Date:   Mon Aug 21 14:43:01 2017 -0400
> > >>
> > >>     Push limit through subqueries to underlying sort, where possible.
> > >>
> > >>     Douglas Doole, reviewed by Ashutosh Bapat and by me.  Minor
> > >formatting
> > >>     change by me.
> > >>
> > >>     Discussion:
> > >>
> > >http://postgr.es/m/CADE5jYLuugnEEUsyW6Q_4mZFYTxHxaVCQmGAsF0yiY8ZDggi-w@mail.gmail.com
> > >
> > >I looked into this and it is usually a detail we don't have in the
> > >release notes.  It isn't generally interesting enough to user.
> >
> > This seems quite relevant. Both because it addresses concerns, but also can lead to a worse plan.

+1.

>
> Well, our normal logical is whether the average user would adjust their
> behavior based on this change, or whether it is user visible.
>

In general, I think this is okay because otherwise providing a lot of
information which most users won't care doesn't serve any purpose.
OTOH, I think it is not easy to decide which features to ignore.  I
think it won't be important to mention some of the code refactoring
commits or minor improvements in the code here and there, but we can't
say that about any of the performance or planner improvements.  Sure,
we might not want to mention everything, but it is better we discuss
such features before ignoring it.  I agree that it will be more work
for preparing release notes, but in the end, we might save some time
by not arguing later about which feature is important and which is
not.

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com

Commits

  1. doc: update PG 11 release notes

  2. Fix misspelled pg_trgm contrib name in PostgreSQL 11 release notes

  3. Doc: clarify release note text about v11's new window function features.

  4. Improve wording of release notes item

  5. Fix typos in release notes

  6. Doc: preliminary list of PG11 major features.

  7. Make numeric power() handle NaNs according to the modern POSIX spec.

  8. Various improvements of skipping index scan during vacuum technics

  9. Revert back-branch changes in power()'s behavior for NaN inputs.

  10. Avoid wrong results for power() with NaN input on more platforms.

  11. Avoid wrong results for power() with NaN input on some platforms.

  12. Skip full index scan during cleanup of B-tree indexes when possible

  13. Rewrite the code that applies scan/join targets to paths.

  14. Postpone generate_gather_paths for topmost scan/join rel.

  15. Add casts from jsonb

  16. Make plpgsql use its DTYPE_REC code paths for composite-type variables.

  17. Don't allow VACUUM VERBOSE ANALYZE VERBOSE.

  18. Pass InitPlan values to workers via Gather (Merge).

  19. Account for the effect of lossy pages when costing bitmap scans.

  20. Allow no-op GiST support functions to be omitted.

  21. Rearm statement_timeout after each executed query.

  22. Push limit through subqueries to underlying sort, where possible.