Horton

Re: Postgres 11 release notes

Alexander Korotkov <a.korotkov@postgrespro.ru>

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From: Alexander Korotkov <a.korotkov@postgrespro.ru>
To: Darafei Praliaskouski <me@komzpa.net>
Cc: Bruce Momjian <bruce@momjian.us>, Andrey Borodin <x4mmm@yandex-team.ru>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2018-06-19T09:15:28Z
Lists: pgsql-hackers 
On Sat, Jun 16, 2018 at 3:57 PM Darafei "Komяpa" Praliaskouski
<me@komzpa.net> wrote:
>>
>> > I'm not sure it is usefull in release notes since it is more about API, and not
>> > user-facing change. Just in case.
>> > GiST opclasses now can omit compress and decompress functions. If compress
>> > function is omited, IndexOnlyScan is enabled for opclass without any extra
>> > change.
>> > https://github.com/postgres/postgres/commit/
>> > d3a4f89d8a3e500bd7c0b7a8a8a5ce1b47859128
>>
>> Uh, we do have this for SP-GiST:
>>
>>         Allow SP-GiST indexes to optionally use compression (Teodor Sigaev,
>>         Heikki Linnakangas, Alexander Korotkov, Nikita Glukhov)
>>
>> I am unclear how far downt the API stack I should go in documenting
>> changes like this.
>
>
> It is also a bit misleading - the idea in that change is that now index representation can be a lossy version of actual data type (a box instead of polygon as a referende, so a changelog entry can tell "Allow SP-GiST index creation for polygon datatype.").  There is no "decompression" for such thing. "compression" sounds like gzip for me in user-facing context.

+1 that current wording looks confusing.  But I think we need to
highlight that we have general SP-GiST improvement, not just support
for particular datatype.  So, I propose following wording: "Allow
SP-GiST to use lossy representation of leaf keys, and add SP-GiST
support for polygon type using that".

I would also like to highlight, that there is a set of typos found my
Liudmila Mantrova in documentation including release notes [1].  As
you know, I'm not native English speaker, but fixes proposed by
Liudmila looks correct for me.

1. https://www.postgresql.org/message-id/275fc450-bbc9-a715-04bb-3b7104fecfcd%40postgrespro.ru

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company

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.