Clarify that the results of nextval and setval are not guaranteed
persistent until the calling transaction commits. Some people
seem to have drawn the opposite conclusion from the statement that
these functions are never rolled back, so re-word to avoid saying
it quite that way.
Discussion: https://postgr.es/m/CAKU4AWohO=NfM-4KiZWvdc+z3c1C9FrUBR6xnReFJ6sfy0i=Lw@mail.gmail.com
Documentation and any code paths related to VS are updated to keep the
whole consistent. Similarly to 2017 and 2019, the version of VS and the
version of nmake that we use to determine which code paths to use for
the build are still inconsistent in their own way.
Backpatch down to 10, so as buildfarm members are able to use this new
version of Visual Studio on all the stable branches supported.
Author: Hans Buschmann
Discussion: https://postgr.es/m/1633101364685.39218@nidsa.net
Backpatch-through: 10
The "See also" section on the reference page for CREATE PUBLICATION
didn't match the cross references on CREATE SUBSCRIPTION and their
ALTER counterparts. Fixed by adding an xref to the CREATE and ALTER
SUBSCRIPTION pages. Backpatch down to v10 where CREATE PUBLICATION
was introduced.
Author: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAHut+PvGWd3-Ktn96c-z6uq-8TGVVP=TPOkEovkEfntoo2mRhw@mail.gmail.com
Backpatch-through: 10
protocol.sgml documented the layout for Type messages, but completely
dropped the ball otherwise, failing to explain what they are, when
they are sent, or what they're good for. While at it, do a little
copy-editing on the description of Relation messages.
In passing, adjust the comment for apply_handle_type() to make it
clearer that we choose not to do anything when receiving a Type
message, not that we think it has no use whatsoever.
Per question from Stefen Hillman.
Discussion: https://postgr.es/m/CAPgW8pMknK5pup6=T4a_UG=Cz80Rgp=KONqJmTdHfaZb0RvnFg@mail.gmail.com
libpq collects up to a bufferload of data whenever it reads data from
the socket. When SSL or GSS encryption is requested during startup,
any additional data received with the server's yes-or-no reply
remained in the buffer, and would be treated as already-decrypted data
once the encryption handshake completed. Thus, a man-in-the-middle
with the ability to inject data into the TCP connection could stuff
some cleartext data into the start of a supposedly encryption-protected
database session.
This could probably be abused to inject faked responses to the
client's first few queries, although other details of libpq's behavior
make that harder than it sounds. A different line of attack is to
exfiltrate the client's password, or other sensitive data that might
be sent early in the session. That has been shown to be possible with
a server vulnerable to CVE-2021-23214.
To fix, throw a protocol-violation error if the internal buffer
is not empty after the encryption handshake.
Our thanks to Jacob Champion for reporting this problem.
Security: CVE-2021-23222
The documentation was imprecise about the starting LSN used for WAL
streaming if nothing can be found in the local archive directory
defined with the pg_receivewal command, so be more talkative on this
matter.
Extracted from a larger patch by the same author.
Author: Ronan Dunklau, Michael Paquier
Discussion: https://postgr.es/m/18708360.4lzOvYHigE@aivenronan
Backpatch-through: 10
queries.sgml failed to mention the rather important point that
INTERSECT binds more tightly than UNION or EXCEPT. I thought
it could also use more discussion of the role of parentheses
in these constructs.
Per gripe from Christopher Painter-Wakefield.
Discussion: https://postgr.es/m/163338891727.12510.3939775743980651160@wrigleys.postgresql.org
The old URL was HTTP 404 and the git link didn't build. Also update two
other ICU links. If we ever get a good link we will add it back.
Reported-by: Anton Voloshin
Author: Laurenz Albe
Backpatch-through: 10
Be a little more vocal about the risks of remote collations not
matching local ones. Actually fixing these risks seems hard,
and I've given up on the idea that it might be back-patchable.
So the best we can do for the back branches is add documentation.
Per discussion of bug #16583 from Jiří Fejfar.
Discussion: https://postgr.es/m/2438715.1632510693@sss.pgh.pa.us
OpenSSL 3 introduced the concept of providers to support modularization,
and moved the outdated ciphers to the new legacy provider. In case it's
not loaded in the users openssl.cnf file there will be a lot of regress
test failures, so add alternative outputs covering those.
Also document the need to load the legacy provider in order to use older
ciphers with OpenSSL-enabled pgcrypto.
This will be backpatched to all supported version once there is sufficient
testing in the buildfarm of OpenSSL 3.
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/FEF81714-D479-4512-839B-C769D2605F8A@yesql.se
Backpatch-through: 9.6
Index vacuums may happen multiple times depending on the number of dead
tuples stored, as of maintenance_work_mem for a manual VACUUM. For
autovacuum, this is controlled by autovacuum_work_mem instead, if set.
The documentation mentioned the former, but not the latter in the
context of autovacuum.
Reported-by: Nikolai Berkoff
Author: Laurenz Albe, Euler Taveira
Discussion: https://postgr.es/m/161545365522.10134.12195402324485546870@wrigleys.postgresql.org
Backpatch-through: 9.6
Formerly, we sent signals for outgoing NOTIFY messages within
ProcessCompletedNotifies, which was also responsible for sending
relevant ones of those messages to our connected client. It therefore
had to run during the main-loop processing that occurs just before
going idle. This arrangement had two big disadvantages:
* Now that procedures allow intra-command COMMITs, it would be
useful to send NOTIFYs to other sessions immediately at COMMIT
(though, for reasons of wire-protocol stability, we still shouldn't
forward them to our client until end of command).
* Background processes such as replication workers would not send
NOTIFYs at all, since they never execute the client communication
loop. We've had requests to allow triggers running in replication
workers to send NOTIFYs, so that's a problem.
To fix these things, move transmission of outgoing NOTIFY signals
into AtCommit_Notify, where it will happen during CommitTransaction.
Also move the possible call of asyncQueueAdvanceTail there, to
ensure we don't bloat the async SLRU if a background worker sends
many NOTIFYs with no one listening.
We can also drop the call of asyncQueueReadAllNotifications,
allowing ProcessCompletedNotifies to go away entirely. That's
because commit 790026972 added a call of ProcessNotifyInterrupt
adjacent to PostgresMain's call of ProcessCompletedNotifies,
and that does its own call of asyncQueueReadAllNotifications,
meaning that we were uselessly doing two such calls (inside two
separate transactions) whenever inbound notify signals coincided
with an outbound notify. We need only set notifyInterruptPending
to ensure that ProcessNotifyInterrupt runs, and we're done.
The existing documentation suggests that custom background workers
should call ProcessCompletedNotifies if they want to send NOTIFY
messages. To avoid an ABI break in the back branches, reduce it
to an empty routine rather than removing it entirely. Removal
will occur in v15.
Although the problems mentioned above have existed for awhile,
I don't feel comfortable back-patching this any further than v13.
There was quite a bit of churn in adjacent code between 12 and 13.
At minimum we'd have to also backpatch 51004c717, and a good deal
of other adjustment would also be needed, so the benefit-to-risk
ratio doesn't look attractive.
Per bug #15293 from Michael Powers (and similar gripes from others).
Artur Zakirov and Tom Lane
Discussion: https://postgr.es/m/153243441449.1404.2274116228506175596@wrigleys.postgresql.org
In ec34040af I added a mention that there was no point in setting
maintenance_work_limit to anything higher than 1GB for vacuum, but that
was incorrect as ginInsertCleanup() also looks at what
maintenance_work_mem is set to during VACUUM and that's not limited to
1GB.
Here I attempt to make it more clear that the limitation is only around
the number of dead tuple identifiers that we can collect during VACUUM.
I've also added a note to autovacuum_work_mem to mention this limitation.
I didn't do that in ec34040af as I'd had some wrong-headed ideas about
just limiting the maximum value for that GUC to 1GB.
Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvpGwOAvunp-E-bN_rbAs3hmxMoasm5pzkYDbf36h73s7w@mail.gmail.com
Backpatch-through: 9.6, same as ec34040af
Since commit e462856a7a, pg_upgrade automatically creates a script to
update extensions, so mention that instead of ALTER EXTENSION.
Backpatch-through: 9.6
Copy-and-pasteo in 665c5855e, evidently. The 9.6 docs toolchain
whined about duplicate index entries, though our modern toolchain
doesn't. In any case, these GUCs surely are not about the
default settings of these values.
postgres_fdw imported generated columns from the remote tables as plain
columns, and caused failures like "ERROR: cannot insert a non-DEFAULT
value into column "foo"" when inserting into the foreign tables, as it
tried to insert values into the generated columns. To fix, we do the
following under the assumption that generated columns in a postgres_fdw
foreign table are defined so that they represent generated columns in
the underlying remote table:
* Send DEFAULT for the generated columns to the foreign server on insert
or update, not generated column values computed on the local server.
* Add to postgresImportForeignSchema() an option "import_generated" to
include column generated expressions in the definitions of foreign
tables imported from a foreign server. The option is true by default.
The assumption seems reasonable, because that would make a query of the
postgres_fdw foreign table return values for the generated columns that
are consistent with the generated expression.
While here, fix another issue in postgresImportForeignSchema(): it tried
to include column generated expressions as column default expressions in
the foreign table definitions when the import_default option was enabled.
Per bug #16631 from Daniel Cherniy. Back-patch to v12 where generated
columns were added.
Discussion: https://postgr.es/m/16631-e929fe9db0ffc7cf%40postgresql.org
It wasn't all that clear which lock levels, if any, would be held on the
DEFAULT partition during an ATTACH PARTITION operation.
Also, clarify which locks will be taken if the DEFAULT partition or the
table being attached are themselves partitioned tables.
Here I'm only backpatching to v12 as before then we obtained an ACCESS
EXCLUSIVE lock on the partitioned table. It seems much less relevant to
mention which locks are taken on other tables when the partitioned table
itself is locked with an ACCESS EXCLUSIVE lock.
Author: Matthias van de Meent, David Rowley
Discussion: https://postgr.es/m/CAEze2WiTB6iwrV8W_J=fnrnZ7fowW3qu-8iQ8zCHP3FiQ6+o-A@mail.gmail.com
Backpatch-through: 12
The error messages using the word "non-negative" are confusing
because it's ambiguous about whether it accepts zero or not.
This commit improves those error messages by replacing it with
less ambiguous word like "greater than zero" or
"greater than or equal to zero".
Also this commit added the note about the word "non-negative" to
the error message style guide, to help writing the new error messages.
When postgres_fdw option fetch_size was set to zero, previously
the error message "fetch_size requires a non-negative integer value"
was reported. This error message was outright buggy. Therefore
back-patch to all supported versions where such buggy error message
could be thrown.
Reported-by: Hou Zhijie
Author: Bharath Rupireddy
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/OS0PR01MB5716415335A06B489F1B3A8194569@OS0PR01MB5716.jpnprd01.prod.outlook.com
Add pg_resetxlog -u option to set the oldest xid in pg_control.
Previously -x set this value be -2 billion less than the -x value.
However, this causes the server to immediately scan all relation's
relfrozenxid so it can advance pg_control's oldest xid to be inside the
autovacuum_freeze_max_age range, which is inefficient and might disrupt
diagnostic recovery. pg_upgrade will use this option to better create
the new cluster to match the old cluster.
Reported-by: Jason Harvey, Floris Van Nee
Discussion: https://postgr.es/m/20190615183759.GB239428@rfd.leadboat.com, 87da83168c644fd9aae38f546cc70295@opammb0562.comp.optiver.com
Author: Bertrand Drouvot
Backpatch-through: 9.6
We had documentation of default_transaction_isolation et al,
but for some reason not of transaction_isolation et al.
AFAICS this is just an ancient oversight, so repair.
Per bug #17077 from Yanliang Lei.
Discussion: https://postgr.es/m/17077-ade8e166a01e1374@postgresql.org
This commit fixes wrong wording like "a fewer kinds"
in the description about track_planning option.
Back-patch to v13 where pg_stat_statements.track_planning was added.
Author: Justin Pryzby
Reviewed-by: Julien Rouhaud, Fujii Masao
Discussion: https://postgr.es/m/20210418233615.GB7256@telsasoft.com
These are the same as world and install-world respectively, but without
building or installing the documentation. There are many reasons for
wanting to be able to do this, including speed, lack of documentation
building tools, and wanting to build other formats of the documentation.
Plans for simplifying the buildfarm client code include using these
targets.
Backpatch to all live branches.
Discussion: https://postgr.es/m/6a421136-d462-b043-a8eb-e75b2861f3df@dunslane.net
The syntax summaries for CREATE FUNCTION and allied commands
made it look like LEAKPROOF is an alternative to
IMMUTABLE/STABLE/VOLATILE, when of course it is an orthogonal
option. Improve that.
Per gripe from aazamrafeeque0. Thanks to David Johnston for
suggestions.
Discussion: https://postgr.es/m/162444349581.694.5818572718530259025@wrigleys.postgresql.org
In a synchronous logical setup, locking [user] catalog tables can cause
deadlock. This is because logical decoding of transactions can lock
catalog tables to access them so exclusively locking those in transactions
can lead to deadlock. To avoid this users must refrain from having
exclusive locks on catalog tables.
Author: Takamichi Osumi
Reviewed-by: Vignesh C, Amit Kapila
Backpatch-through: 9.6
Discussion: https://www.postgresql.org/message-id/20210222222847.tpnb6eg3yiykzpky%40alap3.anarazel.de
PersistHoldablePortal has long assumed that it should store the
entire output of the query-to-be-persisted, which requires rewinding
and re-reading the output. This is problematic if the query is not
stable: we might get different row contents, or even a different
number of rows, which'd confuse the cursor state mightily.
In the case where the cursor is NO SCROLL, this is very easy to
solve: just store the remaining query output, without any rewinding,
and tweak the portal's cursor state to match. Aside from removing
the semantic problem, this could be significantly more efficient
than storing the whole output.
If the cursor is scrollable, there's not much we can do, but it
was already the case that scrolling a volatile query's result was
pretty unsafe. We can just document more clearly that getting
correct results from that is not guaranteed.
There are already prohibitions in place on using SCROLL with
FOR UPDATE/SHARE, which is one way for a SELECT query to have
non-stable results. We could imagine prohibiting SCROLL when
the query contains volatile functions, but that would be
expensive to enforce. Moreover, it could break applications
that work just fine, if they have functions that are in fact
stable but the user neglected to mark them so. So settle for
documenting the hazard.
While this problem has existed in some guise for a long time,
it got a lot worse in v11, which introduced the possibility
of persisting plpgsql cursors (perhaps implicit ones) even
when they violate the rules for what can be marked WITH HOLD.
Hence, I've chosen to back-patch to v11 but not further.
Per bug #17050 from Алексей Булгаков.
Discussion: https://postgr.es/m/17050-f77aa827dc85247c@postgresql.org
The following parameters have been imprecise, or incorrect, about their
description (PGC_POSTMASTER or PGC_SIGHUP):
- autovacuum_work_mem (docs, as of 9.6~)
- huge_page_size (docs, as of 14~)
- max_logical_replication_workers (docs, as of 10~)
- max_sync_workers_per_subscription (docs, as of 10~)
- min_dynamic_shared_memory (docs, as of 14~)
- recovery_init_sync_method (postgresql.conf.sample, as of 14~)
- remove_temp_files_after_crash (docs, as of 14~)
- restart_after_crash (docs, as of 9.6~)
- ssl_min_protocol_version (docs, as of 12~)
- ssl_max_protocol_version (docs, as of 12~)
This commit adjusts the description of all these parameters to be more
consistent with the practice used for the others.
Revewed-by: Justin Pryzby
Discussion: https://postgr.es/m/YK2ltuLpe+FbRXzA@paquier.xyz
Backpatch-through: 9.6
The error messages, docs, and one of the options were using
'parallel degree' to indicate parallelism used by vacuum command. We
normally use 'parallel workers' at other places so change it for parallel
vacuum accordingly.
Author: Bharath Rupireddy
Reviewed-by: Dilip Kumar, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CALj2ACWz=PYrrFXVsEKb9J1aiX4raA+UBe02hdRp_zqDkrWUiw@mail.gmail.com
Formerly we just relied on operator classes that assert longValuesOK
to eventually shorten the leaf value enough to fit on an index page.
That fails since the introduction of INCLUDE-column support (commit
09c1c6ab4), because the INCLUDE columns might alone take up more
than a page, meaning no amount of leaf-datum compaction will get
the job done. At least with spgtextproc.c, that leads to an infinite
loop, since spgtextproc.c won't throw an error for not being able
to shorten the leaf datum anymore.
To fix without breaking cases that would otherwise work, add logic
to spgdoinsert() to verify that the leaf tuple size is decreasing
after each "choose" step. Some opclasses might not decrease the
size on every single cycle, and in any case, alignment roundoff
of the tuple size could obscure small gains. Therefore, allow
up to 10 cycles without additional savings before throwing an
error. (Perhaps this number will need adjustment, but it seems
quite generous right now.)
As long as we've developed this logic, let's back-patch it.
The back branches don't have INCLUDE columns to worry about, but
this seems like a good defense against possible bugs in operator
classes. We already know that an infinite loop here is pretty
unpleasant, so having a defense seems to outweigh the risk of
breaking things. (Note that spgtextproc.c is actually the only
known opclass with longValuesOK support, so that this is all moot
for known non-core opclasses anyway.)
Per report from Dilip Kumar.
Discussion: https://postgr.es/m/CAFiTN-uxP_soPhVG840tRMQTBmtA_f_Y8N51G7DKYYqDh7XN-A@mail.gmail.com
Make sample like_regex match string values of the root object instead of the
whole document. The corrected example seems to represent a more relevant
use case.
Backpatch to 12, when jsonpath was introduced.
Discussion: https://postgr.es/m/13440f8b-4c1f-5875-c8e3-f3f65606af2f%40xs4all.nl
Author: Erik Rijkers
Reviewed-by: Michael Paquier, Alexander Korotkov
Backpatch-through: 12
Mention specifically that you can't call aggregates, window functions,
or procedures this way (the inability to call SRFs was already
mentioned).
Also, the claim that PQfn doesn't support NULL arguments or results
has been a lie since we invented protocol 3.0. Not sure why this
text was never updated for that, but do it now.
Discussion: https://postgr.es/m/2039442.1615317309@sss.pgh.pa.us
For some reason, the "julian" option for extract()/date_part() has
never gotten listed in the manual. Also, while Appendix B mentioned
in passing that we don't conform to the usual astronomical definition
that a Julian date starts at noon UTC, it was kind of vague about what
we do instead. Clarify that, and add an example showing how to get
the astronomical definition if you want it.
It's been like this for ages, so back-patch to all supported branches.
Discussion: https://postgr.es/m/1197050.1619123213@sss.pgh.pa.us
Previously it was documented that if using "-X none" option there was
no guarantee that all required WAL files were archived at the end of
pg_basebackup when taking a backup from the standby. But this limitation
was removed by commit 52f8a59dd9. Now, even when taking a backup
from the standby, pg_basebackup can wait for all required WAL files
to be archived. Therefore this commit removes such obsolete
description from the docs.
Also this commit adds new description about the limitation when
taking a backup from the standby, into the docs. The limitation is that
pg_basebackup cannot force the standbfy to switch to a new WAL file
at the end of backup, which may cause pg_basebackup to wait a long
time for the last required WAL file to be switched and archived,
especially when write activity on the primary is low.
Back-patch to v10 where the issue was introduced.
Reported-by: Kyotaro Horiguchi
Author: Kyotaro Horiguchi, Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/20210420.133235.1342729068750553399.horikyota.ntt@gmail.com
Comment fixes are applied on HEAD, and documentation improvements are
applied on back-branches where needed.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20210408164008.GJ6592@telsasoft.com
Backpatch-through: 9.6
Command-line options, or previous "ALTER (ROLE|DATABASE) ...
SET ROLE ..." commands, can change the value of the default role
for a session. In the presence of one of these, RESET ROLE will
change the current user identifier to the default role rather
than the session user identifier. Fix the documentation to
reflect this reality. Backpatch to all supported versions.
Author: Nathan Bossart
Reviewed-By: Laurenz Albe, David G. Johnston, Joe Conway
Reported by: Nathan Bossart
Discussion: https://postgr.es/m/flat/925134DB-8212-4F60-8AB1-B1231D750CB4%40amazon.com
Backpatch-through: 9.6
The current instructions describing how to write the backup_label and
tablespace_map files are confusing. For example, opening a file in text
mode on Windows and copy-pasting the file's contents would result in a
failure at recovery because of the extra CRLF characters generated. The
documentation was not stating that clearly, and per discussion this is
not considered as a supported scenario.
This commit extends a bit the documentation to mention that it may be
required to open the file in binary mode before writing its data.
Reported-by: Wang Shenhao
Author: David Steele
Reviewed-by: Andrew Dunstan, Magnus Hagander
Discussion: https://postgr.es/m/8373f61426074f2cb6be92e02f838389@G08CNEXMBPEKD06.g08.fujitsu.local
Backpatch-through: 9.6
Some sections of the documentation used "exclusive lock" to describe
that an ACCESS EXCLUSIVE lock is taken during a given operation. This
can be confusing to the reader as ACCESS SHARE is allowed with an
EXCLUSIVE lock is used, but that would not be the case with what is
described on those parts of the documentation.
Author: Greg Rychlewski
Discussion: https://postgr.es/m/CAKemG7VptD=7fNWckFMsMVZL_zzvgDO6v2yVmQ+ZiBfc_06kCQ@mail.gmail.com
Backpatch-through: 9.6
The new appendix groups information on renamed or removed settings,
commands, etc into an out-of-the-way part of the docs.
The original id elements are retained in each subsection to ensure that
the same filenames are produced for HTML docs. This prevents /current/
links on the web from breaking, and allows users of the web docs
to follow links from old version pages to info on the changes in the
new version. Prior to this change, a link to /current/ for renamed
sections like the recovery.conf docs would just 404. Similarly if
someone searched for recovery.conf they would find the pg11 docs,
but there would be no /12/ or /current/ link, so they couldn't easily
find out that it was removed in pg12 or how to adapt.
Index entries are also added so that there's a breadcrumb trail for
users to follow when they know the old name, but not what we changed it
to. So a user who is trying to find out how to set standby_mode in
PostgreSQL 12+, or where pg_resetxlog went, now has more chance of
finding that information.
Craig Ringer and Stephen Frost
Reviewed-by: Euler Taveira
Discussion: https://postgr.es/m/CAGRY4nzPNOyYQ_1-pWYToUVqQ0ThqP5jdURnJMZPm539fdizOg%40mail.gmail.com
Backpatch-through: 10
On partition detach, we acquire a SHARE lock on all tables that
reference the partitioned table that we're detaching a partition from,
but failed to document this fact. My oversight in commit f56f8f8da6.
Repair. Backpatch to 12.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20210325180244.GA12738@alvherre.pgsql
A couple error messages and comments used 'statistic kind', not the
correct 'statistics kind'. Fix and backpatch all the way back to 10,
where extended statistics were introduced.
Backpatch-through: 10
Robert Foggia of Trustwave reported that read_tablespace_map()
fails to prevent an overrun of its on-stack input buffer.
Since the tablespace map file is presumed trustworthy, this does
not seem like an interesting security vulnerability, but still
we should fix it just in the name of robustness.
While here, document that pg_basebackup's --tablespace-mapping option
doesn't work with tar-format output, because it doesn't. To make it
work, we'd have to modify the tablespace_map file within the tarball
sent by the server, which might be possible but I'm not volunteering.
(Less-painful solutions would require changing the basebackup protocol
so that the source server could adjust the map. That's not very
appetizing either.)
GENERATED ALWAYS AS IDENTITY implies NOT NULL, but the code failed
to complain if you overrode that with "GENERATED ALWAYS AS IDENTITY
NULL". One might think the old behavior was a feature, but it was
inconsistent because the outcome varied depending on the order of
the clauses, so it seems to have been just an oversight.
Per bug #16913 from Pavel Boev. Back-patch to v10 where identity
columns were introduced.
Vik Fearing (minor tweaks by me)
Discussion: https://postgr.es/m/16913-3b5198410f67d8c6@postgresql.org
Remove the entire idea of "stale stats" within nbtree VACUUM (stop
caring about stats involving the number of inserted tuples). Also
remove the vacuum_cleanup_index_scale_factor GUC/param on the master
branch (though just disable them on postgres 13).
The vacuum_cleanup_index_scale_factor/stats interface made the nbtree AM
partially responsible for deciding when pg_class.reltuples stats needed
to be updated. This seems contrary to the spirit of the index AM API,
though -- it is not actually necessary for an index AM's bulk delete and
cleanup callbacks to provide accurate stats when it happens to be
inconvenient. The core code owns that. (Index AMs have the authority
to perform or not perform certain kinds of deferred cleanup based on
their own considerations, such as page deletion and recycling, but that
has little to do with pg_class.reltuples/num_index_tuples.)
This issue was fairly harmless until the introduction of the
autovacuum_vacuum_insert_threshold feature by commit b07642db, which had
an undesirable interaction with the vacuum_cleanup_index_scale_factor
mechanism: it made insert-driven autovacuums perform full index scans,
even though there is no real benefit to doing so. This has been tied to
a regression with an append-only insert benchmark [1].
Also have remaining cases that perform a full scan of an index during a
cleanup-only nbtree VACUUM indicate that the final tuple count is only
an estimate. This prevents vacuumlazy.c from setting the index's
pg_class.reltuples in those cases (it will now only update pg_class when
vacuumlazy.c had TIDs for nbtree to bulk delete). This arguably fixes
an oversight in deduplication-related bugfix commit 48e12913.
[1] https://smalldatum.blogspot.com/2021/01/insert-benchmark-postgres-is-still.html
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAD21AoA4WHthN5uU6+WScZ7+J_RcEjmcuH94qcoUPuB42ShXzg@mail.gmail.com
Backpatch: 13-, where autovacuum_vacuum_insert_threshold was added.
Clarify the discussion in "User-Defined Procedures", by laying out
the key differences between functions and procedures in a bulleted
list. Notably, this avoids burying the lede about procedures being
able to do transaction control. Make the back-link in the CREATE
FUNCTION reference page more prominent, and add one in CREATE
PROCEDURE.
Per gripe from Guyren Howe. Thanks to David Johnston for discussion.
Discussion: https://postgr.es/m/BYAPR03MB4903C53A8BB7EFF5EA289674A6949@BYAPR03MB4903.namprd03.prod.outlook.com
Break the synopsis into named parts to make it less confusing.
Make more than zero effort at applying SGML markup. Do a bit
of copy-editing of nearby text.
The synopsis revision is by Alvaro Herrera and Paul Förster,
the rest is my fault. Back-patch to v10 where multi-host
connection strings appeared.
Discussion: https://postgr.es/m/6E752D6B-487C-463E-B6E2-C32E7FB007EA@gmail.com
Building the docs with STYLE=website referenced a stylesheet that long
longer exists on the website, since we changed it to use versioned
references.
To make it less likely for this to happen again, point to a single
stylesheet on the website which will in turn import the required one.
That puts the process entirely within the scope of the website
repository, so next time a version is switched that's the only place
changes have to be made, making them less likely to be missed.
Per (off-list) discussion with Peter Geoghegan and Jonathan Katz.
FreeBSD 13 gained O_DSYNC, which would normally cause wal_sync_method to
choose open_datasync as its default value. That may not be a good
choice for all systems, and performs worse than fdatasync in some
scenarios. Let's preserve the existing default behavior for now.
Like commit 576477e73c, which did the same for Linux, back-patch to all
supported releases.
Discussion: https://postgr.es/m/CA%2BhUKGLsAMXBQrCxCXoW-JsUYmdOL8ALYvaX%3DCrHqWxm-nWbGA%40mail.gmail.com
The manual did not mention whether its return value is (first arg -
second arg) or (second arg - first arg). The order matters because the
return value could have a sign. Fix the manual so that it mentions the
function returns (first arg - second arg).
Patch reviewed by Tom Lane.
Back-patch through v13. Older version's doc format is difficult to add
more description.
Discussion: https://postgr.es/m/flat/20210206.151125.960423226279810864.t-ishii%40sraoss.co.jp
Writing unnecessary '.*' at start and end of a POSIX regex doesn't
do much except confuse the reader about whether that might be
necessary after all. Make the examples in table 9.16 a tad more
realistic, and try to turn the next group of examples into something
self-contained.
Per gripe from rmzgrimes. Back-patch to v13 because it's easy.
Discussion: https://postgr.es/m/161215841824.14653.8969016349304314299@wrigleys.postgresql.org
When the .** jsonpath accessor handles the array, it selects both array and
each of its elements. When using lax mode, subsequent accessors automatically
unwrap arrays. So, the content of each array element may be selected twice.
Even though this behavior is counterintuitive, it's correct because everything
works as designed. This commit documents it.
Backpatch to 12 where the jsonpath language was introduced.
Reported-by: Thomas Kellerer
Bug: #16828
Discussion: https://postgr.es/m/16828-2b0229babfad2d8c%40postgresql.org
Discussion: https://postgr.es/m/CAPpHfdtS-nNidT%3DEqZbAYOPcnNOWh_sd6skVdu2CAQUGdvpT8Q%40mail.gmail.com
Author: Alexandex Korotkov, revised by Tom Lane
Reviewed-by: Alvaro Herrera, Thomas Kellerer, Tom Lane
Backpatch-through: 12
In trying to protect the user from inconsistent behavior, commit
487e9861d0 "Enable BEFORE row-level triggers for partitioned tables"
tried to prevent BEFORE UPDATE FOR EACH ROW triggers from moving the row
from one partition to another. However, it turns out that the
restriction is wrong in two ways: first, it fails spuriously, preventing
valid situations from working, as in bug #16794; and second, they don't
protect from any misbehavior, because tuple routing would cope anyway.
Fix by removing that restriction.
We keep the same restriction on BEFORE INSERT FOR EACH ROW triggers,
though. It is valid and useful there. In the future we could remove it
by having tuple reroute work for inserts as it does for updates.
Backpatch to 13.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Phillip Menke <pg@pmenke.de>
Discussion: https://postgr.es/m/16794-350a655580fbb9ae@postgresql.org
Per a user question, spell out that UNNEST() returns array elements
in storage order; also provide an example to clarify the behavior for
multi-dimensional arrays.
While here, also clarify the SELECT reference page's description of
WITH ORDINALITY. These details were already given in 7.2.1.4, but
a reference page should not omit details.
Back-patch to v13; there's not room in the table in older versions.
Discussion: https://postgr.es/m/FF1FB31F-0507-4F18-9559-2DE6E07E3B43@gmail.com
The page about privilege rights mentioned that TRUNCATE could be applied
to views or even other relation types. This is confusing as this
command can be used only on tables and on partitioned tables.
Oversight in afc4a78.
Reported-by: Harisai Hari
Reviewed-by: Laurenz Albe
Discussion: https://postgr.es/m/161157636877.14625.15340884663716426087@wrigleys.postgresql.org
Backpatch-through: 12
In light of recent discussions, we should instruct people to
install Apple's command line tools; installing Xcode is secondary.
Also, fix sample command for finding out the default sysroot,
as we now know that the command originally recommended can give
a result that doesn't match your OS version.
Also document the workaround to use if you really don't want
configure to select a sysroot at all.
Discussion: https://postgr.es/m/20210119111625.20435-1-james.hilliard1@gmail.com
This text claimed that the reconnection would occur "to the same
server", but there is no such guarantee in the code, nor would
insisting on that be an improvement.
Back-patch to v10 where multi-host connection strings were added.
Discussion: https://postgr.es/m/1095901.1611268376@sss.pgh.pa.us
When a tablespace is used in a partitioned relation (per commits
ca4103025d in pg12 for tables and 33e6c34c32 in pg11 for indexes),
it is possible to drop the tablespace, potentially causing various
problems. One such was reported in bug #16577, where a rewriting ALTER
TABLE causes a server crash.
Protect against this by using pg_shdepend to keep track of tablespaces
when used for relations that don't keep physical files; we now abort a
tablespace if we see that the tablespace is referenced from any
partitioned relations.
Backpatch this to 11, where this problem has been latent all along. We
don't try to create pg_shdepend entries for existing partitioned
indexes/tables, but any ones that are modified going forward will be
protected.
Note slight behavior change: when trying to drop a tablespace that
contains both regular tables as well as partitioned ones, you'd
previously get ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE and now you'll
get ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST. Arguably, the latter is more
correct.
It is possible to add protecting pg_shdepend entries for existing
tables/indexes, by doing
ALTER TABLE ONLY some_partitioned_table SET TABLESPACE pg_default;
ALTER TABLE ONLY some_partitioned_table SET TABLESPACE original_tablespace;
for each partitioned table/index that is not in the database default
tablespace. Because these partitioned objects do not have storage, no
file needs to be actually moved, so it shouldn't take more time than
what's required to acquire locks.
This query can be used to search for such relations:
SELECT ... FROM pg_class WHERE relkind IN ('p', 'I') AND reltablespace <> 0
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/16577-881633a9f9894fd5@postgresql.org
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
The point of this restriction is to avoid trying to substitute variables
into timestamp literal values, which may contain strings like '12:34'.
There is a good deal more that should be done to reduce pgbench's
tendency to substitute where it shouldn't. But this is sufficient to
solve the case complained of by Jaime Soler, and it's simple enough
to back-patch.
Back-patch to v11; before commit 9d36a3866, pgbench had a slightly
different definition of what a variable name is, and anyway it seems
unwise to change long-stable branches for this.
Fabien Coelho
Discussion: https://postgr.es/m/alpine.DEB.2.22.394.2006291740420.805678@pseudo
The default value of recovery_target_timeline was changed in v12,
but the description about the default behavior of that was not updated.
Back-patch to v12 where the default behavior of recovery_target_timeline
was changed.
Author: Benoit Lobréau
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CAPE8EZ7c3aruEmM24GYkj8y8WmHKD1m9TtPtgCF0nQ3zw4LCkQ@mail.gmail.com
The behavior of cross-type comparisons among date/time data types was
not really explained anywhere. You could probably infer it if you
recognized the applicability of comments elsewhere about datatype
conversions, but it seems worthy of explicit documentation.
Per bug #16797 from Dana Burd.
Discussion: https://postgr.es/m/16797-f264b0b980b53b8b@postgresql.org
secure_open_gssapi() installed the krb_server_keyfile setting as
KRB5_KTNAME unconditionally, so long as it's not empty. However,
pg_GSS_recvauth() only installed it if KRB5_KTNAME wasn't set already,
leading to a troubling inconsistency: in theory, clients could see
different sets of server principal names depending on whether they
use GSSAPI encryption. Always using krb_server_keyfile seems like
the right thing, so make both places do that. Also fix up
secure_open_gssapi()'s lack of a check for setenv() failure ---
it's unlikely, surely, but security-critical actions are no place
to be sloppy.
Also improve the associated documentation.
This patch does nothing about secure_open_gssapi()'s use of setenv(),
and indeed causes pg_GSS_recvauth() to use it too. That's nominally
against project portability rules, but since this code is only built
with --with-gssapi, I do not feel a need to do something about this
in the back branches. A fix will be forthcoming for HEAD though.
Back-patch to v12 where GSSAPI encryption was introduced. The
dubious behavior in pg_GSS_recvauth() goes back further, but it
didn't have anything to be inconsistent with, so let it be.
Discussion: https://postgr.es/m/2187460.1609263156@sss.pgh.pa.us
90fbf7c has taken care of that for HEAD. This includes the portion of
the fixes that applies to the documentation, where needed depending on
the branch.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20201227202604.GC26311@telsasoft.com
Backpatch-through: 9.5
Unrecoverable errors detected by GSSAPI encryption can't just be
reported with elog(ERROR) or elog(FATAL), because attempting to
send the error report to the client is likely to lead to infinite
recursion or loss of protocol sync. Instead make this code do what
the SSL encryption code has long done, which is to just report any
such failure to the server log (with elevel COMMERROR), then pretend
we've lost the connection by returning errno = ECONNRESET.
Along the way, fix confusion about whether message translation is done
by pg_GSS_error() or its callers (the latter should do it), and make
the backend version of that function work more like the frontend
version.
Avoid allocating the port->gss struct until it's needed; we surely
don't need to allocate it in the postmaster.
Improve logging of "connection authorized" messages with GSS enabled.
(As part of this, I back-patched the code changes from dc11f31a1.)
Make BackendStatusShmemSize() account for the GSS-related space that
will be allocated by CreateSharedBackendStatus(). This omission
could possibly cause out-of-shared-memory problems with very high
max_connections settings.
Remove arbitrary, pointless restriction that only GSS authentication
can be used on a GSS-encrypted connection.
Improve documentation; notably, document the fact that libpq now
prefers GSS encryption over SSL encryption if both are possible.
Per report from Mikael Gustavsson. Back-patch to v12 where
this code was introduced.
Discussion: https://postgr.es/m/e5b0b6ed05764324a2f3fe7acfc766d5@smhi.se
The jsonb || jsonb operator arbitrarily rejected certain combinations
of scalar and non-scalar inputs, while being willing to concatenate
other combinations. This was of course quite undocumented. Rather
than trying to document it, let's just remove the restriction,
creating a uniform rule that unless we are handling an object-to-object
concatenation, non-array inputs are converted to one-element arrays,
resulting in an array-to-array concatenation. (This does not change
the behavior for any case that didn't throw an error before.)
Per complaint from Joel Jacobson. Back-patch to all supported branches.
Discussion: https://postgr.es/m/163099.1608312033@sss.pgh.pa.us
The separate "cd" command before invoking psql made sense (or at least
I thought so) when it was added in commit ed1939332. But 4e3a61635
removed the supporting text that explained when to use it, making it
just confusing. So drop it.
Also switch from four-dot to three-dot filler for the unsupplied
part of the path, since at least one person has read the four-dot
filler as a typo for "../..". And fix these/those inconsistency.
Discussion: https://postgr.es/m/160837647714.673.5195186835607800484@wrigleys.postgresql.org
It was not clear how COPY TO behaved with partitioning/inheritance
because the paragraphs were so far apart. Also reword to simplify.
Discussion: https://postgr.es/m/20201203211723.GR24052@telsasoft.com
Author: Justin Pryzby
Backpatch-through: 10
The SQL standard says that redundant unique constraints are disallowed,
but we long ago decided that throwing an error would be too
user-unfriendly, so we just drop redundant ones. The docs weren't very
clear about that though, as this behavior was only explained for PRIMARY
KEY vs UNIQUE, not UNIQUE vs UNIQUE.
While here, I couldn't resist doing some copy-editing and markup-fixing
on the adjacent text about INCLUDE options.
Per bug #16767 from Matthias vd Meent.
Discussion: https://postgr.es/m/16767-1714a2056ca516d0@postgresql.org
In a few places, the long-version options were listed before the
single-letter ones in the command summary of a few commands. This
didn't match other commands, and didn't match the option ordering later
in the same reference page.
Backpatch-through: 9.5
Because regular CREATE INDEX commands are independent, and there's no
logical data dependency, it's not immediately obvious that transactions
held by concurrent index builds on one table will block the second phase
of concurrent index creation on an unrelated table, so document this
caveat.
Backpatch this all the way back. In branch master, mention that only
some indexes are involved.
Author: James Coleman <jtc331@gmail.com>
Reviewed-by: David Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAAaqYe994=PUrn8CJZ4UEo_S-FfRr_3ogERyhtdgHAb2WG_Ufg@mail.gmail.com
Checking for DocBook being installed was valuable when we were on the
OpenSP docs toolchain, because that was rather hard to get installed
fully. Nowadays, as long as you have xmllint and xsltproc installed,
you're good, because those programs will fetch the DocBook files off
the net at need. Moreover, testing this at configure time means that
a network access may well occur whether or not you have any interest
in building the docs later. That can be slow (typically 2 or 3
seconds, though much higher delays have been reported), and it seems
not very nice to be doing an off-machine access without warning, too.
Hence, drop the PGAC_CHECK_DOCBOOK probe, and adjust related
documentation. Without that macro, there's not much left of
config/docbook.m4 at all, so I just removed it.
Back-patch to v11, where we started to use xmllint in the
PGAC_CHECK_DOCBOOK probe.
Discussion: https://postgr.es/m/E2EE6B76-2D96-408A-B961-CAE47D1A86F0@yesql.se
Discussion: https://postgr.es/m/A55A7FC9-FA60-47FE-98B5-139CDC57CE6E@gmail.com
Through my misreading of what the existing code actually did,
commits 85c54287a et al. broke psql's behavior for the case where
"\c connstring" provides a password in the connstring. We should
use that password in such a case, but as of 85c54287a we ignored it
(and instead, prompted for a password).
Commit 94929f1cf fixed that in HEAD, but since I thought it was
cleaning up a longstanding misbehavior and not one I'd just created,
I didn't back-patch it.
Hence, back-patch the portions of 94929f1cf having to do with
password management. In addition to fixing the introduced bug,
this means that "\c -reuse-previous=on connstring" will allow
re-use of an existing connection's password if the connstring
doesn't change user/host/port. That didn't happen before, but
it seems like a bug fix, and anyway I'm loath to have significant
differences in this code across versions.
Also fix an error with the same root cause about whether or not to
override a connstring's setting of client_encoding. As of 85c54287a
we always did so; restore the previous behavior of overriding only
when stdin/stdout are a terminal and there's no environment setting
of PGCLIENTENCODING. (I find that definition a bit surprising, but
right now doesn't seem like the time to revisit it.)
Per bug #16746 from Krzysztof Gradek. As with the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16746-44b30e2edf4335d4@postgresql.org
The documentation omitted the critical tidbit that a keyword-array entry
is simply ignored if its corresponding value-array entry is NULL or an
empty string; it will *not* override any previously-obtained value for
the parameter. (See conninfo_array_parse().) I'd supposed that would
force the setting back to default, which is what led me into bug #16746;
but it doesn't.
While here, I couldn't resist the temptation to do some copy-editing,
both in the description of PQconnectdbParams() and in the section
about connection URI syntax.
Discussion: https://postgr.es/m/931505.1606618746@sss.pgh.pa.us