PostgreSQL Weekly News - May 23, 2021

# PostgreSQL Weekly News - May 23, 2021

PostgreSQL 14 Beta 1 released. [Test!](https://www.postgresql.org/about/news/postgresql-14-beta-1-released-2213/)

The official IRC channels have moved from Freenode to Libera. Details
[here](https://www.postgresql.org/about/news/migration-of-postgresql-irc-channels-2216/).

# PostgreSQL Product News

DBD::Pg 3.15.0, a Perl driver for PostgreSQL, [released](https://github.com/bucardo/dbdpg).

pg_back 2.0.1, is a tool that can dump PostgreSQL databases to files, [released](https://github.com/orgrim/pg_back).

# PostgreSQL Jobs for May

[https://archives.postgresql.org/pgsql-jobs/2021-05/](https://archives.postgresql.org/pgsql-jobs/2021-05/)

# PostgreSQL in the News

Planet PostgreSQL: [https://planet.postgresql.org/](https://planet.postgresql.org/)

PostgreSQL Weekly News is brought to you this week by David Fetter

Submit news and announcements by Sunday at 3:00pm PST8PDT to david(at)fetter(dot)org(dot)

# Applied Patches

Bruce Momjian pushed:

- doc: update PG 14 relnotes from feedback by Tom, Alvaro, Julien.
[https://git.postgresql.org/pg/commitdiff/07af57dbad589bbef9d7178d9b1cb354412e823f](https://git.postgresql.org/pg/commitdiff/07af57dbad589bbef9d7178d9b1cb354412e823f)

- doc: PG 14 relnotes adjustments from Fujii Masao.
[https://git.postgresql.org/pg/commitdiff/fe2fb9ebcae8445fdb3915ecf8402a3a887effc2](https://git.postgresql.org/pg/commitdiff/fe2fb9ebcae8445fdb3915ecf8402a3a887effc2)

- doc: add PG 14 rel item about vacuum_cleanup_index_scale_factor.
[https://git.postgresql.org/pg/commitdiff/2e7c17837064297f25c427d58154dce8d4287302](https://git.postgresql.org/pg/commitdiff/2e7c17837064297f25c427d58154dce8d4287302)

- doc: partial completion of XML markup for PG 14 release notes.
[https://git.postgresql.org/pg/commitdiff/6a5bde7d4f96ef153578eaeb624ae12e48b46e85](https://git.postgresql.org/pg/commitdiff/6a5bde7d4f96ef153578eaeb624ae12e48b46e85)

- doc: add xreflabel for libpq chapter, needed for PG 14 relnotes.
[https://git.postgresql.org/pg/commitdiff/1e7d53bd019e9d86ef1013308715622a2e400d3b](https://git.postgresql.org/pg/commitdiff/1e7d53bd019e9d86ef1013308715622a2e400d3b)

- doc: revert 1e7d53bd01 so libpq chapter number is accessable. Fix PG 14
relnotes to use <link> instead of <xref>. This was discussed in commit
message 59fa7eb603.
[https://git.postgresql.org/pg/commitdiff/4f7d1c30966cc02fd5eba2f0d51d1f53be07d457](https://git.postgresql.org/pg/commitdiff/4f7d1c30966cc02fd5eba2f0d51d1f53be07d457)

- doc: change PG 14 relnotes as suggested by Justin Pryzby.
[https://git.postgresql.org/pg/commitdiff/4f586fe244a296d7c781de3f06c54755f2ae222b](https://git.postgresql.org/pg/commitdiff/4f586fe244a296d7c781de3f06c54755f2ae222b)

- doc: more XML markup for PG 14 release notes.
[https://git.postgresql.org/pg/commitdiff/55370f8db96c8416940ad0b05be7a00a9f059a9f](https://git.postgresql.org/pg/commitdiff/55370f8db96c8416940ad0b05be7a00a9f059a9f)

- doc: complete adding XML markup to PG 14 relnotes.
[https://git.postgresql.org/pg/commitdiff/0cdaa05b40e9f28e5d6d58ccd06fe19f3cd920c9](https://git.postgresql.org/pg/commitdiff/0cdaa05b40e9f28e5d6d58ccd06fe19f3cd920c9)

- Update PG 14 relnotes for vacuum_cost_page_miss. Reported-by: Peter Geoghegan
Discussion:
[https://postgr.es/m/CAH2-WzmgSnDX9WVoxRZxuKeCy2MzLO9Dmo4+go0RzNW0VBdhmw@mail.gmail.com](https://postgr.es/m/CAH2-WzmgSnDX9WVoxRZxuKeCy2MzLO9Dmo4+go0RzNW0VBdhmw@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/8dcae7f0a3d6aba1afad1599ab18d259c417b4ee](https://git.postgresql.org/pg/commitdiff/8dcae7f0a3d6aba1afad1599ab18d259c417b4ee)

- doc: PG 14 relnotes, adjust `pg_{read|write}_all_data` entry. Reported-by:
Stephen Frost Discussion:
[https://postgr.es/m/20210522232945.GO20766@tamriel.snowman.net](https://postgr.es/m/20210522232945.GO20766@tamriel.snowman.net)
[https://git.postgresql.org/pg/commitdiff/7ce7d07e1c5fb33ee56bda235ae3d53f162f3bc0](https://git.postgresql.org/pg/commitdiff/7ce7d07e1c5fb33ee56bda235ae3d53f162f3bc0)

- doc: word-wrap and indent PG 14 relnotes.
[https://git.postgresql.org/pg/commitdiff/8f73ed6b659464274eb9cc8358588b569960d0be](https://git.postgresql.org/pg/commitdiff/8f73ed6b659464274eb9cc8358588b569960d0be)

Etsuro Fujita pushed:

- Doc: Update documentation for asynchronous execution. Add a note of caution on
the performance of asynchronous execution by postgres_fdw. Follow-up for
commit 27e1f1456. Stephen Frost, a little bit expanded by me. Discussion:
[https://postgr.es/m/20210506171224.GV20766%40tamriel.snowman.net](https://postgr.es/m/20210506171224.GV20766%40tamriel.snowman.net)
[https://git.postgresql.org/pg/commitdiff/15fcd33e0694428d0567a6796891b759bc91e6f9](https://git.postgresql.org/pg/commitdiff/15fcd33e0694428d0567a6796891b759bc91e6f9)

Magnus Hagander pushed:

- Fix wording in description of pg_stat_statements.toplevel. Incorrect wording
got applied in 7531fcb1fcf. Reported-By: Fujii Masao Discussion:
[https://postgr.es/m/e5512912-eac9-b163-df2b-e2601ce06d27@oss.nttdata.com](https://postgr.es/m/e5512912-eac9-b163-df2b-e2601ce06d27@oss.nttdata.com)
[https://git.postgresql.org/pg/commitdiff/f9e6d00df029144fd8f4ec70c52b5a1d2444f895](https://git.postgresql.org/pg/commitdiff/f9e6d00df029144fd8f4ec70c52b5a1d2444f895)

- Remove obsolete reference to winflex download. We used to distribute a binary
version of flex for windows on our download site, but it hasn't been working
for many years. The "old documentation" referenced was also for versions that
have been EOL for many years. So, remove it. Discussion:
[https://postgr.es/m/CABUevEwXLJpVpab62f7AFXNWQ5=U0kvErCLq4VEsikidLyzSQg@mail.gmail.com](https://postgr.es/m/CABUevEwXLJpVpab62f7AFXNWQ5=U0kvErCLq4VEsikidLyzSQg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/cff8436f19e1c0c278f1ee96d450507fbd43f9ef](https://git.postgresql.org/pg/commitdiff/cff8436f19e1c0c278f1ee96d450507fbd43f9ef)

Peter Eisentraut pushed:

- Translation updates. Source-Git-URL:
git://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash:
9bbd9c3714d0c76daaa806588b1fbf744aa60496
[https://git.postgresql.org/pg/commitdiff/6292b83074243db94df89271842bda0877cbc4ce](https://git.postgresql.org/pg/commitdiff/6292b83074243db94df89271842bda0877cbc4ce)

- Put some psql documentation pieces back into alphabetical order.
[https://git.postgresql.org/pg/commitdiff/124966c1a35b950210e12048e64533963960febd](https://git.postgresql.org/pg/commitdiff/124966c1a35b950210e12048e64533963960febd)

Tom Lane pushed:

- Stamp 14beta1.
[https://git.postgresql.org/pg/commitdiff/e4f9737fac77a5cb03a84d1f4038d300ffd28afd](https://git.postgresql.org/pg/commitdiff/e4f9737fac77a5cb03a84d1f4038d300ffd28afd)

- Avoid creating testtablespace directories where not wanted. Recently we
refactored things so that pg_regress makes the "testtablespace" subdirectory
used by the core regression tests, instead of doing that in the makefiles.
That had the undesirable side effect of making such a subdirectory in every
directory that has "input" or "output" test files. Since these subdirectories
remain empty, git doesn't complain about them, but nonetheless they're
clutter. To fix, invent an explicit --make-testtablespace-dir switch, so that
pg_regress only makes the subdirectory when explicitly told to. Discussion:
[https://postgr.es/m/2854388.1621284789@sss.pgh.pa.us](https://postgr.es/m/2854388.1621284789@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/413c1ef98e0c9c708c4a9a13a838a55b65b16a80](https://git.postgresql.org/pg/commitdiff/413c1ef98e0c9c708c4a9a13a838a55b65b16a80)

- Clean up cpluspluscheck violation. "typename" is a C++ keyword, so
pg_upgrade.h fails to compile in C++. Fortunately, there seems no likely
reason for somebody to need to do that. Nonetheless, it's project policy that
all .h files should pass cpluspluscheck, so rename the argument to fix that.
Oversight in 57c081de0; back-patch as that was. (The policy requiring
pg_upgrade.h to pass cpluspluscheck only goes back to v12, but it seems best
to keep this code looking the same in all branches.)
[https://git.postgresql.org/pg/commitdiff/6d59a218c38adf5b993200a804713df4982a0c75](https://git.postgresql.org/pg/commitdiff/6d59a218c38adf5b993200a804713df4982a0c75)

- Avoid detoasting failure after COMMIT inside a plpgsql FOR loop.
exec_for_query() normally tries to prefetch a few rows at a time from the
query being iterated over, so as to reduce executor entry/exit overhead.
Unfortunately this is unsafe if we have COMMIT or ROLLBACK within the loop,
because there might be TOAST references in the data that we prefetched but
haven't yet examined. Immediately after the COMMIT/ROLLBACK, we have no
snapshots in the session, meaning that VACUUM is at liberty to remove
recently-deleted TOAST rows. This was originally reported as a case
triggering the "no known snapshots" error in init_toast_snapshot(), but even
if you miss hitting that, you can get "missing toast chunk", as illustrated by
the added isolation test case. To fix, just disable prefetching in non-atomic
contexts. Maybe there will be performance complaints prompting us to work
harder later, but it's not clear at the moment that this really costs much,
and I doubt we'd want to back-patch any complicated fix. In passing, adjust
that error message in init_toast_snapshot() to be a little clearer about the
likely cause of the problem. Patch by me, based on earlier investigation by
Konstantin Knizhnik. Per bug #15990 from Andreas Wicht. Back-patch to v11
where intra-procedure COMMIT was added. Discussion:
[https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org](https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org)
[https://git.postgresql.org/pg/commitdiff/f21fadafaf0fb5ea4c9622d915972651273d62ce](https://git.postgresql.org/pg/commitdiff/f21fadafaf0fb5ea4c9622d915972651273d62ce)

- Restore the portal-level snapshot after procedure COMMIT/ROLLBACK.
COMMIT/ROLLBACK necessarily destroys all snapshots within the session. The
original implementation of intra-procedure transactions just cavalierly did
that, ignoring the fact that this left us executing in a rather different
environment than normal. In particular, it turns out that handling of toasted
datums depends rather critically on there being an outer ActiveSnapshot:
otherwise, when SPI or the core executor pop whatever snapshot they used and
return, it's unsafe to dereference any toasted datums that may appear in the
query result. It's possible to demonstrate "no known snapshots" and "missing
chunk number N for toast value" errors as a result of this oversight.
Historically this outer snapshot has been held by the Portal code, and that
seems like a good plan to preserve. So add infrastructure to pquery.c to
allow re-establishing the Portal-owned snapshot if it's not there anymore, and
add enough bookkeeping support that we can tell whether it is or not. We
can't, however, just re-establish the Portal snapshot as part of
COMMIT/ROLLBACK. As in normal transaction start, acquiring the first snapshot
should wait until after SET and LOCK commands. Hence, teach spi.c about doing
this at the right time. (Note that this patch doesn't fix the problem for any
PLs that try to run intra-procedure transactions without using SPI to execute
SQL commands.) This makes SPI's no_snapshots parameter rather a misnomer, so
in HEAD, rename that to allow_nonatomic. replication/logical/worker.c also
needs some fixes, because it wasn't careful to hold a snapshot open around
AFTER trigger execution. That code doesn't use a Portal, which I suspect
someday we're gonna have to fix. But for now, just rearrange the order of
operations. This includes back-patching the recent addition of finish_estate()
to centralize the cleanup logic there. This also back-patches commit
2ecfeda3e into v13, to improve the test coverage for worker.c (it was that
test that exposed that worker.c's snapshot management is wrong). Per bug
#15990 from Andreas Wicht. Back-patch to v11 where intra-procedure COMMIT was
added. Discussion:
[https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org](https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org)
[https://git.postgresql.org/pg/commitdiff/84f5c2908dad81e8622b0406beea580e40bb03ac](https://git.postgresql.org/pg/commitdiff/84f5c2908dad81e8622b0406beea580e40bb03ac)

- Fix usage of "tableoid" in GENERATED expressions. We consider this supported
(though I've got my doubts that it's a good idea, because tableoid is not
immutable). However, several code paths failed to fill the field in soon
enough, causing such a GENERATED expression to see zero or the wrong value.
This occurred when ALTER TABLE adds a new GENERATED column to a table with
existing rows, and during regular INSERT or UPDATE on a foreign table with
GENERATED columns. Noted during investigation of a report from Vitaly
Ustinov. Back-patch to v12 where GENERATED came in. Discussion:
[https://postgr.es/m/CAM_DEiWR2DPT6U4xb-Ehigozzd3n3G37ZB1+867zbsEVtYoJww@mail.gmail.com](https://postgr.es/m/CAM_DEiWR2DPT6U4xb-Ehigozzd3n3G37ZB1+867zbsEVtYoJww@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/2b0ee126bbf01cbfd657bd53c94f9284ba903ca2](https://git.postgresql.org/pg/commitdiff/2b0ee126bbf01cbfd657bd53c94f9284ba903ca2)

- Disallow whole-row variables in GENERATED expressions. This was previously
allowed, but I think that was just an oversight. It's a clear violation of the
rule that a generated column cannot depend on itself or other generated
columns. Moreover, because the code was relying on the assumption that no
such cross-references exist, it was pretty easy to crash ALTER TABLE and
perhaps other places. Even if you managed not to crash, you got quite
unstable, implementation-dependent results. Per report from Vitaly Ustinov.
Back-patch to v12 where GENERATED came in. Discussion:
[https://postgr.es/m/CAM_DEiWR2DPT6U4xb-Ehigozzd3n3G37ZB1+867zbsEVtYoJww@mail.gmail.com](https://postgr.es/m/CAM_DEiWR2DPT6U4xb-Ehigozzd3n3G37ZB1+867zbsEVtYoJww@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/4b10074453d182b5fc11a5667bab2ef8532ff3a6](https://git.postgresql.org/pg/commitdiff/4b10074453d182b5fc11a5667bab2ef8532ff3a6)

- Remove plpgsql's special-case code paths for SET/RESET. In the wake of
84f5c2908, it's no longer necessary for plpgsql to handle SET/RESET specially.
The point of that was just to avoid taking a new transaction snapshot
prematurely, which the regular code path through `_SPI_execute_plan()` now does
just fine (in fact better, since it now does the right thing for LOCK too).
Hence, rip out a few lines of code, going back to the old way of treating
SET/RESET as a generic SQL command. This essentially reverts all but the test
cases from b981275b6. Discussion:
[https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org](https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org)
[https://git.postgresql.org/pg/commitdiff/30168be8f75b95183abccf48f0da7a64a0cfbd9f](https://git.postgresql.org/pg/commitdiff/30168be8f75b95183abccf48f0da7a64a0cfbd9f)

- Fix access to no-longer-open relcache entry in logical-rep worker. If we
redirected a replicated tuple operation into a partition child table, and then
tried to fire AFTER triggers for that event, the relation cache entry for the
child table was already closed. This has no visible ill effects as long as
the entry is still there and still valid, but an unluckily-timed cache flush
could result in a crash or other misbehavior. To fix, postpone the
ExecCleanupTupleRouting call (which is what closes the child table) until
after we've fired triggers. This requires a bit of refactoring so that the
cleanup function can have access to the necessary state. In HEAD, I took the
opportunity to simplify some of worker.c's function APIs based on use of the
new ApplyExecutionData struct. However, it doesn't seem safe/practical to
back-patch that aspect, at least not without a lot of analysis of possible
interactions with a04daa97a. In passing, add an Assert to
afterTriggerInvokeEvents to catch such cases. This seems worthwhile because
we've grown a number of fairly unstructured ways of calling
AfterTriggerEndQuery. Back-patch to v13, where worker.c grew the ability to
deal with partitioned target tables. Discussion:
[https://postgr.es/m/3382681.1621381328@sss.pgh.pa.us](https://postgr.es/m/3382681.1621381328@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/b39630fd41f25b414d0ea9b30804f4105f2a0aff](https://git.postgresql.org/pg/commitdiff/b39630fd41f25b414d0ea9b30804f4105f2a0aff)

- Be more verbose when the postmaster unexpectedly quits. Emit a LOG message
when the postmaster stops because of a failure in the startup process. There
already is a similar message if we exit for that reason during PM_STARTUP
phase, so it seems inconsistent that there was none if the startup process
fails later on. Also emit a LOG message when the postmaster stops after a
crash because restart_after_crash is disabled. This seems potentially helpful
in case DBAs (or developers) forget that that's set. Also, it was the only
remaining place where the postmaster would do an abnormal exit without any
comment as to why. In passing, remove an unreachable call of
ExitPostmaster(0). Discussion:
[https://postgr.es/m/194914.1621641288@sss.pgh.pa.us](https://postgr.es/m/194914.1621641288@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/bc2a389efb3b52d259cefd53c16cfa00742116f2](https://git.postgresql.org/pg/commitdiff/bc2a389efb3b52d259cefd53c16cfa00742116f2)

- Re-order pg_attribute columns to eliminate some padding space. Now that
attcompression is just a char, there's a lot of wasted padding space after it.
Move it into the group of char-wide columns to save a net of 4 bytes per
pg_attribute entry. While we're at it, swap the order of attstorage and
attalign to make for a more logical grouping of these columns. Also re-order
actions in related code to match the new field ordering. This patch also
fixes one outright bug: equalTupleDescs() failed to compare attcompression.
That could, for example, cause relcache reload to fail to adopt a new value
following a change. Michael Paquier and Tom Lane, per a gripe from Andres
Freund. Discussion:
[https://postgr.es/m/20210517204803.iyk5wwvwgtjcmc5w@alap3.anarazel.de](https://postgr.es/m/20210517204803.iyk5wwvwgtjcmc5w@alap3.anarazel.de)
[https://git.postgresql.org/pg/commitdiff/f5024d8d7b04de2f5f4742ab433cc38160354861](https://git.postgresql.org/pg/commitdiff/f5024d8d7b04de2f5f4742ab433cc38160354861)

David Rowley pushed:

- Fix typo and outdated information in README.barrier. README.barrier didn't
seem to get the memo when atomics were added. Fix that. Author: Tatsuo Ishii,
David Rowley Discussion:
[https://postgr.es/m/20210516.211133.2159010194908437625.t-ishii%40sraoss.co.jp](https://postgr.es/m/20210516.211133.2159010194908437625.t-ishii%40sraoss.co.jp)
Backpatch-through: 9.6, oldest supported release
[https://git.postgresql.org/pg/commitdiff/2ded19fa3a4dafbae80245710fa371d5163bdad4](https://git.postgresql.org/pg/commitdiff/2ded19fa3a4dafbae80245710fa371d5163bdad4)

- Fix planner's use of Result Cache with unique joins. When the planner
considered using a Result Cache node to cache results from the inner side of a
Nested Loop Join, it failed to consider that the inner path's parameterization
may not be the entire join condition. If the join was marked as inner_unique
then we may accidentally put the cache in singlerow mode. This meant that
entries would be marked as complete after caching the first row. That was
wrong as if only part of the join condition was parameterized then the
uniqueness of the unique join was not guaranteed at the Result Cache's level.
The uniqueness is only guaranteed after Nested Loop applies the join filter.
If subsequent rows were found, this would lead to: ERROR: cache entry already
complete This could have been fixed by only putting the cache in singlerow
mode if the entire join condition was parameterized. However, Nested Loop
will only read its inner side so far as the first matching row when the join
is unique, so that might mean we never get an opportunity to mark cache
entries as complete. Since non-complete cache entries are useless for
subsequent lookups, we just don't bother considering a Result Cache path in
this case. In passing, remove the XXX comment that claimed the above ERROR
might be better suited to be an Assert. After there being an actual case
which triggered it, it seems better to keep it an ERROR. Reported-by: David
Christensen Discussion:
[https://postgr.es/m/CAOxo6X+dy-V58iEPFgst8ahPKEU+38NZzUuc+a7wDBZd4TrHMQ@mail.gmail.com](https://postgr.es/m/CAOxo6X+dy-V58iEPFgst8ahPKEU+38NZzUuc+a7wDBZd4TrHMQ@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/9e215378d7fbb7d4615be917917c52f246cc6c61](https://git.postgresql.org/pg/commitdiff/9e215378d7fbb7d4615be917917c52f246cc6c61)

Michaël Paquier pushed:

- Add --no-toast-compression to pg_dumpall. This is an oversight from bbe0a81d,
where the equivalent option exists in pg_dump. This is useful to be able to
reset the compression methods cluster-wide when restoring the data based on
default_toast_compression. Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion:
[https://postgr.es/m/YKHC+qCJvzCRVCpY@paquier.xyz](https://postgr.es/m/YKHC+qCJvzCRVCpY@paquier.xyz)
[https://git.postgresql.org/pg/commitdiff/694da1983e9569b2a2f96cd786ead6b8dba31f1d](https://git.postgresql.org/pg/commitdiff/694da1983e9569b2a2f96cd786ead6b8dba31f1d)

Fujii Masao pushed:

- Fix issues in pg_stat_wal. 1) Previously there were both pgstat_send_wal() and
pgstat_report_wal() in order to send WAL activity to the stats collector.
With the former being used by wal writer, the latter by most other
processes. They were a bit redundant and so this commit merges them into
pgstat_send_wal() to simplify the code. 2) Previously WAL global
statistics counters were calculated and then compared with zero-filled
buffer in order to determine whether any WAL activity has happened since
the last submission. These calculation and comparison were not cheap. This
was regularly exercised even in read-only workloads. This commit fixes the
issue by making some WAL activity counters directly be checked to determine
if there's WAL activity stats to send. 3) Previously pgstat_report_stat()
did not check if there's WAL activity stats to send as part of the "Don't
expend a clock check if nothing to do" check at the top. It's probably rare
to have pending WAL stats without also passing one of the other conditions,
but for safely this commit changes pgstat_report_stats() so that it checks
also some WAL activity counters at the top. This commit also adds the
comments about the design of WAL stats. Reported-by: Andres Freund Author:
Masahiro Ikeda Reviewed-by: Kyotaro Horiguchi, Atsushi Torikoshi, Andres
Freund, Fujii Masao Discussion:
[https://postgr.es/m/20210324232224.vrfiij2rxxwqqjjb@alap3.anarazel.de](https://postgr.es/m/20210324232224.vrfiij2rxxwqqjjb@alap3.anarazel.de)
[https://git.postgresql.org/pg/commitdiff/d8735b8b4651f5ed50afc472e236a8e6120f07f2](https://git.postgresql.org/pg/commitdiff/d8735b8b4651f5ed50afc472e236a8e6120f07f2)

- Make standby promotion reset the recovery pause state to 'not paused'. If a
promotion is triggered while recovery is paused, the paused state ends and
promotion continues. But previously in that case
pg_get_wal_replay_pause_state() returned 'paused' wrongly while a promotion
was ongoing. This commit changes a standby promotion so that it marks the
recovery pause state as 'not paused' when it's triggered, to fix the issue.
Author: Fujii Masao Reviewed-by: Dilip Kumar, Kyotaro Horiguchi Discussion:
[https://postgr.es/m/f706876c-4894-0ba5-6f4d-79803eeea21b@oss.nttdata.com](https://postgr.es/m/f706876c-4894-0ba5-6f4d-79803eeea21b@oss.nttdata.com)
[https://git.postgresql.org/pg/commitdiff/167bd4804995afd654bd97ca9486acbece24377e](https://git.postgresql.org/pg/commitdiff/167bd4804995afd654bd97ca9486acbece24377e)

Amit Kapila pushed:

- Fix 020_messages.pl test. We were not waiting for a publisher to catch up with
the subscriber after creating a subscription. Now, it can happen that apply
worker starts replication even after we have disabled the subscription in the
test. This will make the test expect that there is no active slot whereas
there exists one. Fix this symptom by allowing the publisher to wait for
catching up with the subscription. It is not a good idea to ensure if the
slot is still active by checking for walsender existence as we release the
slot after we clean up the walsender related memory. Fix that by checking the
slot status in pg_replication_slots. Also, it is better to avoid repeated
enabling/disabling of the subscription. Finally, we make autovacuum off for
this test to avoid any empty transaction appearing in the test while consuming
changes. Reported-by: as per buildfarm Author: Vignesh C Reviewed-by: Amit
Kapila, Michael Paquier Discussion:
[https://postgr.es/m/CAA4eK1+uW1UGDHDz-HWMHMen76mKP7NJebOTZN4uwbyMjaYVww@mail.gmail.com](https://postgr.es/m/CAA4eK1+uW1UGDHDz-HWMHMen76mKP7NJebOTZN4uwbyMjaYVww@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/0a442a408b40d2c6710de7e5397cb2e769d8c630](https://git.postgresql.org/pg/commitdiff/0a442a408b40d2c6710de7e5397cb2e769d8c630)

- Fix deadlock for multiple replicating truncates of the same table. While
applying the truncate change, the logical apply worker acquires
RowExclusiveLock on the relation being truncated. This allowed truncate on the
relation at a time by two apply workers which lead to a deadlock. The reason
was that one of the workers after updating the pg_class tuple tries to acquire
SHARE lock on the relation and started to wait for the second worker which has
acquired RowExclusiveLock on the relation. And when the second worker tries to
update the pg_class tuple, it starts to wait for the first worker which leads
to a deadlock. Fix it by acquiring AccessExclusiveLock on the relation before
applying the truncate change as we do for normal truncate operation. Author:
Peter Smith, test case by Haiying Tang Reviewed-by: Dilip Kumar, Amit Kapila
Backpatch-through: 11 Discussion:
[https://postgr.es/m/CAHut+PsNm43p0jM+idTvWwiGZPcP0hGrHMPK9TOAkc+a4UpUqw@mail.gmail.com](https://postgr.es/m/CAHut+PsNm43p0jM+idTvWwiGZPcP0hGrHMPK9TOAkc+a4UpUqw@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/6d0eb38557155855539cd007f04736dc3b2ba16f](https://git.postgresql.org/pg/commitdiff/6d0eb38557155855539cd007f04736dc3b2ba16f)

Dean Rasheed pushed:

- Fix pgbench permute tests. One of the tests for the pgbench permute() function
added by 6b258e3d68 fails on some 32-bit platforms, due to variations in the
floating point computations in getrand(). The remaining tests give sufficient
coverage, so just remove the failing test. Reported by Christoph Berg.
Analysis by Thomas Munro and Tom Lane. Based on patch by Fabien Coelho.
Discussion:
[https://postgr.es/m/YKQnUoYV63GRJBDD@msg.df7cb.de](https://postgr.es/m/YKQnUoYV63GRJBDD@msg.df7cb.de)
[https://git.postgresql.org/pg/commitdiff/0f516d039d8023163e82fa51104052306068dd69](https://git.postgresql.org/pg/commitdiff/0f516d039d8023163e82fa51104052306068dd69)

Andrew Dunstan pushed:

- Use a more portable way to get the version string in PostgresNode. Older
versions of perl on Windows don't like the list form of pipe open, and
perlcritic doesn't like the string form of open, so we avoid both with a
simpler formulation using qx{}. Per complaint from Amit Kapila.
[https://git.postgresql.org/pg/commitdiff/8bdd6f563aa2456de602e78991e6a9f61b8ec86d](https://git.postgresql.org/pg/commitdiff/8bdd6f563aa2456de602e78991e6a9f61b8ec86d)

- Install PostgresVersion.pm. A lamentable oversight on my part meant that when
PostgresVersion.pm was added in commit 4c4eaf3d19 provision to install it was
not added to the Makefile, so it was not installed along with the other perl
modules.
[https://git.postgresql.org/pg/commitdiff/bdbb2ce7d51e93ca2ec68e25e2fafb271b34e72d](https://git.postgresql.org/pg/commitdiff/bdbb2ce7d51e93ca2ec68e25e2fafb271b34e72d)

# Pending Patches

Yugo Nagata sent in another revision of a patch to implement incrementally
materialized views.

Amul Sul sent in another revision of a patch to separate the WAL writing code
from StartupXLOG(), implement WAL prohibit state using global barriers, error or
Assert before START_CRIT_SECTION for WAL write, and document all this. This is
infrastructure for, among other things, ALTER SYSTEM READ {ONLY | WRITE}.

Pavel Stěhule sent in another revision of a patch to implement schema variables.

Bharath Rupireddy sent in another revision of a patch to avoid catalog accesses
in slot_store_error_callback and conversion_error_callback.

Amit Langote sent in a patch to reword some comments in pathnodes.h for clarity.

Ranier Vilela sent in another revision of a patch to fix a possible memory
corruption in zic.

Bharath Rupireddy sent in three revisions of a patch to tighten up batch_size
and fetch_size options against non-numeric values in the PostgreSQL FDW.

Masahiro Ikeda sent in two more revisions of a patch to improve the performance
of reporting WAL stats without introducing a new variable.

Hou Zhijie and Amit Langote traded patches to skip partition tuple routing when
there is a constant partition key.

Peter Smith and Ajin Cherian traded patches to add support for prepared
transactions to built-in logical replication, add prepare API support for
streaming transactions, and skip empty transactions for logical replication.

Amit Langote sent in four more revisions of a patch to pgoutput to fix memory
management of RelationSyncEntry.map by releasing memory allocated when creating
the tuple-conversion map and its component TupleDescs when its owning sync entry
is invalidated and freeing TupleDescs when no map is deemed necessary to begin
with.

Nitin Jadhav sent in two more revisions of a patch to remove an extra malloc
from create_list_bounds(), allocate the PartitionListValue as a single chunk, do
the same in create_hash_bounds for PartitionHashBound, allocate datum arrays in
bulk to avoid palloc overhead, and pfree intermediate results in
create_range_bounds().

Bertrand Drouvot sent in another revision of a patch to keep oldestxid in
pgupgrade.

Andrew Dunstan sent in another revision of a patch to implement SQL/JSON
functions.

Andrew Dunstan sent in another revision of a patch to implement SQL/JSON
JSON_TABLE.

Matthias van de Meent sent in another revision of a patch to improve the usage
of line pointer array truncation in heapam.

Heikki Linnakangas sent in a patch to allow specifying pg_waldump --rmgr option
multiple times.

Robert Haas, Dilip Kumar, and Kyotaro HORIGUCHI traded patches intended to
fix a bug that manifested as a race condition in recovery.

Takashi Menjo sent in another revision of a patch to map WAL segment files on
PMEM as WAL buffers.

Justin Pryzby sent in another revision of a patch to implement different
compression methods for FPI.

Takamichi Osumi sent in a patch to disallow TRUNCATE on user_catalog_table.

Peter Eisentraut and Álvaro Herrera traded patches to add a NO_INSTALL option to
pgxs.

Bharath Rupireddy sent in three more revisions of a patch to disambiguate error
messages that use "non-negative".

Daniel Gustafsson sent in two revisions of a patch to extend
configure_test_server_for_ssl to add extensions, and add tests for sslinfo.

Mathis Rudolf sent in a patch intended to fix a bug that manifested as an alias
collision in REFRESH MATERIALIZED VIEW CONCURRENTLY by adding adds the prefix
`_pg_internal_` to aliases like 'mv' and 'newdata' in
'refresh_by_match_merge()', which makes it unlikely to cause any collisions with
user-created MVs.

Yura Sokolov sent in a patch to add a PortalDrop call to exec_execute_message().

Bharath Rupireddy and Peter Smith traded patches to refactor "mutually exclusive
options" error reporting code in parse_subscription_options.

Michaël Paquier sent in another revision of a patch to switch tests of
pg_upgrade to use TAP.

Greg Nancarrow sent in another revision of a patch to fix a parallel worker
failed assertion and coredump.

Kirill Reshke sent in a patch intended to fix a bug that manifested as slow
standby snapshot by using a doubly linked list in KnownAssignedXids.

Paul Guo sent in a patch to fix a pg_rewind failure due to read only file open()
error by making it writable.

Alexander Pyhalov sent in a patch to make it possible to push joins with
function RTEs to PostgreSQL data sources.

Nitin Jadhav sent in another revision of a patch to support tzh tzm patterns.

Michaël Paquier sent in a patch to force disable of SSL renegotiation in the
server.

Ivan Panchenko sent in another revision of a patch to make it possible to
trigger actions on login.

Takayuki Tsunakawa sent in another revision of a patch to propagate CTE property
flags in the rewriter.

Ashutosh Bapat sent in two revisions of a patch to report new catalog_xmin
candidate in LogicalIncreaseXminForSlot().

Michaël Paquier sen in another revision of a patch to add authenticated data to
pg_stat_activity.

Bharath Rupireddy sent in another revision of a patch to reword error messages
and docs for parallel vacuum.

Hou Zhijie sent in two revisions of a patch intended to fix a bug that
manifested as caused FDW batched inserts to fail when batch_size `>` 65535.

Dmitry Dolgov sent in another revision of a patch to implement index skip scans.

Tomáš Vondra sent in a patch intended to fix a bug that manifested as
performance degradation of REFRESH MATERIALIZED VIEW.

Michaël Paquier and Tom Lane traded patches to reduce the memory footprint of
the pg_attribute struct.

David Rowley sent in another revision of a patch to speed up NOT IN() with a set
of Consts.

Vigneshwaran C sent in another revision of a patch to add tab completion for
missing options in PUBLICATION and SUBSCRIPTION commands.