Horton

Re: NaNs in numeric_power (was Re: Postgres 11 release notes)

David Rowley <david.rowley@2ndquadrant.com>

View thread View on postgr.es
From: David Rowley <david.rowley@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Bruce Momjian <bruce@momjian.us>, Đặng Minh Hướng <kakalot49@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2018-05-16T21:49:18Z
Lists: pgsql-hackers 
On 16 May 2018 at 09:55, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> David Rowley <david.rowley@2ndquadrant.com> writes:
>> On 16 May 2018 at 02:01, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> I'm not particularly fussed about getting credit for that.  However,
>>> looking again at how that patch series turned out --- ie, that
>>> we ensured POSIX behavior for NaNs only in HEAD --- I wonder
>>> whether we shouldn't do what was mentioned in the commit log for
>>> 6bdf1303, and teach numeric_pow() about these same special cases.
>>> It seems like it would be more consistent to change both functions
>>> for v11, rather than letting that other shoe drop in some future
>>> major release.
>
>> I'm inclined to agree. It's hard to imagine these two functions
>> behaving differently in regards to NaN input is useful to anyone.
>
> Here's a proposed patch for that.

Looks good to me.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

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.