Horton

Re: PG 18 release notes draft committed

Atsushi Torikoshi <torikoshia.tech@gmail.com>

View thread
From: Atsushi Torikoshi <torikoshia.tech@gmail.com>
To: Bruce Momjian <bruce@momjian.us>
Cc: PostgreSQL-development <pgsql-hackers@lists.postgresql.org>
Date: 2025-05-04T13:41:30Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. doc PG 18 relnotes: add AFTER trigger user change item

  2. doc PG 18 relnotes: modify async I/O item for other improvements

  3. doc PG 18 relnotes: split apart log_connections item

  4. doc PG 18 relnotes: move ANALYZE item,split ANALYZE/EXPLAIN item

  5. doc PG 18 relnotes: clarify multiplication item

  6. doc PG 18 relnotes: add removal details to MD5 item

  7. doc PG 18 relnotes: fix markup

  8. doc PG 18 relnotes: clarify btree skip-scan item

  9. doc PG 18 relnotes: update to current

  10. doc PG 18 relnotes: adjust CREATE SUBSCRIPTION attribution

  11. doc PG 18 relnotes: clarify btree skip scan item

  12. doc PG 18 relnotes: mv. hash joins and GROUP BY item to General

  13. Add support for runtime arguments in injection points

  14. doc PG 18 relnotes: fix missing parens for crc32c()

  15. PG 18 relnotes: adjust RETURNING new/old item

  16. doc PG 18 relnotes: adjust pg_log_backend_memory_contexts()

  17. doc PG 18 relnotes: add pg_log_backend_memory_contexts() mention

  18. doc PG 18 relnotes: adjust pgbench per-script reporting item

  19. doc PG 18 relnotes: mention GROUP SET fixes

  20. doc PG 18 relnotes: adjust partition planning item

  21. doc PG 18 relnotes: small adjustments regarding options

  22. doc PG 18 relnotes: move partition locking item to General Perf

  23. doc PG 18 relnotes: adjust partition items

  24. doc PG 18 relnotes: reword OAuth item

  25. doc PG 18 relnotes: add mention of pg_stat_reset_backend_stats()

  26. doc PG 18 relnotes: adjust hash item

  27. doc PG 18 relnotes: split partition optimizer item into two

  28. doc PG 18 relnotes: adjust COPY and REJECT_LIMIT items

  29. doc PG 18 relnotes: move and clarify constraint items

  30. doc PG 18 relnotes: add commit for cancel key and protocol neg.

  31. doc PG 18 relnotes: fix libpq wording

  32. doc PG 18 relnotes: add GROUP BY column elimination item

  33. doc PG 18 relnotes: move protocol version item to "server"

  34. doc PG 18 relnotes: adjust libpq trace & potocol version items

  35. doc PG 18 relnotes: reword and reorder items

  36. doc: Fix memory context level in pg_log_backend_memory_contexts() example.

  37. Make levels 1-based in pg_log_backend_memory_contexts()

  38. Introduce file_copy_method setting.

  39. libpq: Handle NegotiateProtocolVersion message differently

  40. Add timingsafe_bcmp(), for constant-time memory comparison

  41. Optimization for lower(), upper(), casefold() functions.

  42. Fix ALTER SUBSCRIPTION ... SET PUBLICATION ... command.

  43. Add connection establishment duration logging

  44. Modularize log_connections output

  45. Ensure that AFTER triggers run as the instigating user.

  46. Detect redundant GROUP BY columns using UNIQUE indexes

  47. Move cancel key generation to after forking the backend

Hi,

On Fri, May 2, 2025 at 11:44 AM Bruce Momjian <bruce@momjian.us> wrote:
>
> I have committd the first draft of the PG 18 release notes.  The item
> count looks strong:
>
>         release-7.4:  263
>         release-8.0:  230
>         release-8.1:  174
>         release-8.2:  215
>         release-8.3:  214
>         release-8.4:  314
>         release-9.0:  237
>         release-9.1:  203
>         release-9.2:  238
>         release-9.3:  177
>         release-9.4:  211
>         release-9.5:  193
>         release-9.6:  214
>         release-10:   189
>         release-11:   170
>         release-12:   180
>         release-13:   178
>         release-14:   220
>         release-15:   184
>         release-16:   206
>         release-17:   182
>         release-18:   209
>
> I will continue improving it until beta 1, and until the final release.
> I will probably add markup in 1-3 weeks.  Let the feedback begin.  ;-)

Thanks for your work!

> Add REJECT_LIMIT to control the number of invalid rows COPY IN can ignore (Atsushi Torikoshi)

Since REJECT_LIMIT cannot be used with COPY IN but can be used with
COPY FROM, I think "IN" should be "FROM".

  =# COPY t1 TO '/tmp/a' WITH (REJECT_LIMIT 3);
  ERROR:  COPY REJECT_LIMIT requires ON_ERROR to be set to IGNORE
  =# COPY t1 TO '/tmp/a' WITH ( ON_ERROR ignore, REJECT_LIMIT 3);
  ERROR:  COPY ON_ERROR cannot be used with COPY TO
  LINE 1: COPY t1 to '/tmp/a' WITH (ON_ERROR ignore, REJECT_LIMIT 3);


> This is active when ON_ERROR = 'ignore'.

As a non-native English speaker, I may be misunderstanding this, but
the word "active" might suggest that REJECT_LIMIT always takes effect
by default, causing the COPY operation to stop after a certain number
of errors.
However, in reality, REJECT_LIMIT does not have any effect by default
— unless explicitly set, there is no limit on the number of rows that
can be skipped when ON_ERROR is set to ignore.
To avoid this potential confusion, a phrasing like:

  This option must be used with ON_ERROR ignore.

might be clearer.

Also, in the v17 release notes, COPY option values are not enclosed in
single quotes but written in <literal> tag.
For consistency, it might be better to follow the same style in the
v18 notes as well.

  -- https://www.postgresql.org/docs/current/release-17.html
  Add new COPY option ON_ERROR ignore to discard error rows
  The default behavior is ON_ERROR stop


> Add COPY log_verbosity level "silent" to suppress all log output (Atsushi Torikoshi)

Similarly, in the v17 release notes, the log_verbosity option was
written in uppercase (LOG_VERBOSITY).
For consistency, it may be preferable to use the same case formatting
in this entry as well.

  -- https://www.postgresql.org/docs/current/release-17.html
  Add new COPY option LOG_VERBOSITY which reports COPY FROM ignored error rows

Also, the phrase "suppress all log output" may be slightly misleading.
Even with log_verbosity = 'silent', COPY still outputs logs — it only
suppresses log messages related to skipped rows when ON_ERROR ignore
is used.
It might help to clarify this nuance to avoid confusion.
For example, how about "Add COPY LOG_VERBOSITY silent to suppress logs
related to skipped rows"?


> Add on_error and log_verbosity options to file_fdw (Atsushi Torikoshi)
> Add REJECT_LIMIT to control the number of invalid rows file_fdw can ignore (Atsushi Torikoshi)
> This is active when ON_ERROR = 'ignore'.

The case of option names for file_fdw is inconsistent — some are
lowercase (on_error, log_verbosity), while others use uppercase
(REJECT_LIMIT, ON_ERROR).
For consistency, it might be better to standardize the option names
throughout the release notes.
Since the file_fdw documentation consistently uses lowercase for all
options, using lowercase in the release notes as well might feel more
natural.


--
Regards,
Atsushi Torikoshi