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6793 commits

Author SHA1 Message Date
Tom Lane
97d6716723 Fix failure for generated column with a not-null domain constraint.
If a GENERATED column is declared to have a domain data type where
the domain's constraints disallow null values, INSERT commands failed
because we built a targetlist that included coercing a null constant
to the domain's type.  The failure occurred even when the generated
value would have been perfectly OK.  This is adjacent to the issues
fixed in 0da39aa76, but we didn't notice for lack of testing a domain
with such a constraint.

We aren't going to use the result of the targetlist entry for the
generated column --- ExecComputeStoredGenerated will overwrite it.
So it's not really necessary that it have the exact datatype of
the generated column.  This patch fixes the problem by changing
the targetlist entry to be a null Const of the domain's base type,
which should be sufficiently legal.  (We do have to tweak
ExecCheckPlanOutput to accept the situation, though.)

This has been broken since we implemented generated columns.
However, this patch only applies easily as far back as v14, partly
because I (tgl) only carried 0da39aa76 back that far, but mostly
because v14 significantly refactored the handling of INSERT/UPDATE
targetlists.  Given the lack of field complaints and the short
remaining support lifetime of v13, I judge the cost-benefit ratio
not good for devising a version that would work in v13.

Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACJufxG59tip2+9h=rEv-ykOFjt0cbsPVchhi0RTij8bABBA0Q@mail.gmail.com
Backpatch-through: 14
2025-04-15 12:08:34 -04:00
Tom Lane
ede29a1e40 Fix parse_cte.c's failure to examine sub-WITHs in DML statements.
makeDependencyGraphWalker thought that only SelectStmt nodes could
contain a WithClause.  Which was true in our original implementation
of WITH, but astonishingly we missed updating this code when we added
the ability to attach WITH to INSERT/UPDATE/DELETE (and later MERGE).
Moreover, since it was coded to deliberately block recursion to a
WithClause, even updating raw_expression_tree_walker didn't save it.

The upshot of this was that we didn't see references to outer CTE
names appearing within an inner WITH, and would neither complain about
disallowed recursion nor account for such references when sorting CTEs
into a usable order.  The lack of complaints about this is perhaps not
so surprising, because typical usage of WITH wouldn't hit either case.
Still, it's pretty broken; failing to detect recursion here leads to
assert failures or worse later on.

Fix by factoring out the processing of sub-WITHs into a new function
WalkInnerWith, and invoking that for all the statement types that
can have WITH.

Bug: #18878
Reported-by: Yu Liang <luy70@psu.edu>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18878-a26fa5ab6be2f2cf@postgresql.org
Backpatch-through: 13
2025-04-05 15:01:33 -04:00
Tom Lane
f5069f0264 Repair misbehavior with duplicate entries in FK SET column lists.
Since v15 we've had an option to apply a foreign key constraint's
ON DELETE SET DEFAULT or SET NULL action to just some of the
referencing columns.  There was not a check for duplicate entries in
the list of columns-to-set, though.  That caused a potential memory
stomp in CreateConstraintEntry(), which incautiously assumed that
the list of columns-to-set couldn't be longer than the number of key
columns.  Even after fixing that, the case doesn't work because you
get an error like "multiple assignments to same column" from the SQL
command that is generated to do the update.

We could either raise an error for duplicate columns or silently
suppress the dups, and after a bit of thought I chose to do the
latter.  This is motivated by the fact that duplicates in the FK
column list are legal, so it's not real clear why duplicates
in the columns-to-set list shouldn't be.  Of course there's no
need to actually set the column more than once.

I left in the fix in CreateConstraintEntry() too, just because
it didn't seem like such low-level code ought to be making
assumptions about what it's handed.

Bug: #18879
Reported-by: Yu Liang <luy70@psu.edu>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18879-259fc59d072bd4d7@postgresql.org
Backpatch-through: 15
2025-04-04 20:11:48 -04:00
Fujii Masao
7b565bad85 Fix logical decoding test to correctly check slot removal on standby.
The regression test for logical decoding verifies whether a logical slot
is correctly dropped on a standby when its associated database is dropped.
However, the test mistakenly retrieved slot information from the primary
instead of the standby, causing incorrect behavior.

This commit fixes the issue by ensuring the test correctly checks the slot
on the standby.

Back-patch to all supported versions.

Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/1fdfd020-a509-403c-bd8f-a04664aba148@oss.nttdata.com
Backpatch-through: 13
2025-04-04 13:34:04 +09:00
Fujii Masao
84fe9f1eb3 Fix logical decoding regression tests to correctly check slot existence.
The regression tests for logical decoding verify whether a logical slot
exists or has been dropped. Previously, these tests attempted to
retrieve "slot_name" from the result of slot(), but since "slot_name" was
not included in the result, slot()->{'slot_name'} always returned undef,
leading to incorrect behavior.

This commit fixes the issue by checking the "plugin" field in the result
of slot() instead, ensuring the tests properly verify slot existence.

Back-patch to all supported versions.

Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB149667EC4E738769CA80B7EA5F5AE2@OSCPR01MB14966.jpnprd01.prod.outlook.com
Backpatch-through: 13
2025-04-04 13:11:05 +09:00
Tom Lane
2d6cfb0cdd Need to do CommandCounterIncrement after StoreAttrMissingVal.
Without this, an additional change to the same pg_attribute row
within the same command will fail.  This is possible at least with
ALTER TABLE ADD COLUMN on a multiple-inheritance-pathway structure.
(Another potential hazard is that immediately-following operations
might not see the missingval.)

Introduced by 95f650674, which split the former coding that
used a single pg_attribute update to change both atthasdef and
atthasmissing/attmissingval into two updates, but missed that
this should entail two CommandCounterIncrements as well.  Like
that fix, back-patch through v13.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/025a3ffa-5eff-4a88-97fb-8f583b015965@gmail.com
Backpatch-through: 13
2025-04-02 11:13:01 -04:00
Dean Rasheed
14a33d3f0a Fix MERGE with DO NOTHING actions into a partitioned table.
ExecInitPartitionInfo() duplicates much of the logic in
ExecInitMerge(), except that it failed to handle DO NOTHING
actions. This would cause an "unknown action in MERGE WHEN clause"
error if a MERGE with any DO NOTHING actions attempted to insert into
a partition not already initialised by ExecInitModifyTable().

Bug: #18871
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Gurjeet Singh <gurjeet@singh.im>
Discussion: https://postgr.es/m/18871-b44e3c96de3bd2e8%40postgresql.org
Backpatch-through: 15
2025-03-29 09:52:18 +00:00
Tom Lane
13dd6f7726 Fix ARRAY_SUBLINK and ARRAY[] for int2vector and oidvector input.
If the given input_type yields valid results from both
get_element_type and get_array_type, initArrayResultAny believed the
former and treated the input as an array type.  However this is
inconsistent with what get_promoted_array_type does, leading to
situations where the output of an ARRAY() subquery is labeled with
the wrong type: it's labeled as oidvector[] but is really a 2-D
array of OID.  That at least results in strange output, and can
result in crashes if further processing such as unnest() is applied.
AFAIK this is only possible with the int2vector and oidvector
types, which are special-cased to be treated mostly as true arrays
even though they aren't quite.

Fix by switching the logic to match get_promoted_array_type by
testing get_array_type not get_element_type, and remove an Assert
thereby made pointless.  (We need not introduce a symmetrical
check for get_element_type in the other if-branch, because
initArrayResultArr will check it.)  This restores the behavior
that existed before bac27394a introduced initArrayResultAny:
the output really is int2vector[] or oidvector[].

Comparable confusion exists when an input of an ARRAY[] construct
is int2vector or oidvector: transformArrayExpr decides it's dealing
with a multidimensional array constructor, and we end up with
something that's a multidimensional OID array but is alleged to be
of type oidvector.  I have not found a crashing case here, but it's
easy to demonstrate totally-wrong results.  Adjust that code so
that what you get is an oidvector[] instead, for consistency with
ARRAY() subqueries.  (This change also makes these types work like
domains-over-arrays in this context, which seems correct.)

Bug: #18840
Reported-by: yang lei <ylshiyu@126.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18840-fbc9505f066e50d6@postgresql.org
Backpatch-through: 13
2025-03-13 16:07:55 -04:00
Tom Lane
ae0be2f0bd Build whole-row Vars the same way during parsing and planning.
makeWholeRowVar() has different rules for constructing a
whole-row Var depending on the kind of RTE it's representing.
This turns out to be problematic because the rewriter and planner
can convert view RTEs and set-returning-function RTEs into
subquery RTEs; so a whole-row Var made during planning might
look different from one made by the parser.  In isolation this
doesn't cause any problem, but if a query contains Vars made
both ways for the same varno, there are cross-checks in the
executor that will complain.  This manifests for UPDATE, DELETE,
and MERGE queries that use whole-row table references.

To fix, we need makeWholeRowVar() to produce the same result
from an inlined RTE as it would have for the original.  For
an inlined view, we can use RangeTblEntry.relid to detect
that this had been a view RTE.  For inlined SRFs, make a
data structure definition change akin to commit 47bb9db75,
and say that we won't clear RangeTblEntry.functions until
the end of planning.  That allows makeWholeRowVar() to
repeat what it would have done with the unmodified RTE.

Reported-by: Duncan Sands <duncan.sands@deepbluecap.com>
Reported-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Diagnosed-by: Tender Wang <tndrwang@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/3518c50a-ab18-482f-b916-a37263622501@deepbluecap.com
Backpatch-through: 13
2025-03-12 11:47:19 -04:00
Álvaro Herrera
bf1e2d2db5
Fix ALTER TABLE error message
This bogus error message was introduced in 2013 by commit f177cbfe67,
because of misunderstanding the processCASbits() API; at the time, no
test cases were added that would be affected by this change.  Only in
ca87c415e2 was one added (along with a couple of typos), with an XXX
note that the error message was bogus.  Fix the whole, add some test
cases.

Backpatch all the way back.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/202503041822.aobpqke3igvb@alvherre.pgsql
2025-03-04 20:07:30 +01:00
Tom Lane
1d180931cc Fix broken handling of domains in atthasmissing logic.
If a domain type has a default, adding a column of that type (without
any explicit DEFAULT clause) failed to install the domain's default
value in existing rows, instead leaving the new column null.  This
is unexpected, and it used to work correctly before v11.  The cause
is confusion in the atthasmissing mechanism about which default value
to install: we'd only consider installing an explicitly-specified
default, and then we'd decide that no table rewrite is needed.

To fix, take the responsibility for filling attmissingval out of
StoreAttrDefault, and instead put it into ATExecAddColumn's existing
logic that derives the correct value to fill the new column with.
Also, centralize the logic that determines the need for
default-related table rewriting there, instead of spreading it over
four or five places.

In the back branches, we'll leave the attmissingval-filling code
in StoreAttrDefault even though it's now dead, for fear that some
extension may be depending on that functionality to exist there.
A separate HEAD-only patch will clean up the now-useless code.

Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACJufxHFssPvkP1we7WMhPD_1kwgbG52o=kQgL+TnVoX5LOyCQ@mail.gmail.com
Backpatch-through: 13
2025-03-03 12:43:29 -05:00
Michael Paquier
f9b76fd696 test_escape: Fix output of --help
The short option name -f was not listed, only its long option name
--force-unsupported.

Author: Japin Li
Discussion: https://postgr.es/m/ME0P300MB04452BD1FB1B277D4C1C20B9B6C52@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
Backpatch-through: 13
2025-02-20 09:31:05 +09:00
Andres Freund
70b650d185 tests: BackgroundPsql: Fix potential for lost errors on windows
This addresses various corner cases in BackgroundPsql:

- On windows stdout and stderr may arrive out of order, leading to errors not
  being reported, or attributed to the wrong statement.

  To fix, emit the "query-separation banner" on both stdout and stderr and
  wait for both.

- Very occasionally the "query-separation banner" would not get removed, because
  we waited until the banner arrived, but then replaced the banner plus
  newline.

  To fix, wait for banner and newline.

- For interactive psql replacing $banner\n is not sufficient, interactive psql
  outputs \r\n.

- For interactive psql, where commands are echoed to stdout, the \echo
  command, rather than its output, would be matched.

  This would sometimes lead to output from the prior query, or wait_connect(),
  being returned in the next command.

  This also affected wait_connect(), leading to sometimes sending queries to
  psql before the connection actually was established.

While debugging these issues I also found that it's hard to know whether a
query separation banner was attributed to the right query. Make that easier by
counting the queries each BackgroundPsql instance has emitted and include the
number in the banner.

Also emit psql stdout/stderr in query() and wait_connect() as Test::More
notes, without that it's rather hard to debug some issues in CI and buildfarm.

As this can cause issues not just to-be-added tests, but also existing ones,
backpatch the fix to all supported versions.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/wmovm6xcbwh7twdtymxuboaoarbvwj2haasd3sikzlb3dkgz76@n45rzycluzft
Backpatch-through: 13
2025-02-19 10:46:45 -05:00
Andres Freund
c0bc11aebb backport: Extend background_psql() to be able to start asynchronously
This is a backport of ba08edb065. Originally it was only applied to master,
but I (Andres) am planning to fix a few bugs in BackgroundPsql, which would be
somewhat harder with the behavioural differences across branches. It's also
generally good for test infrastructure to behave similarly across branches, to
avoid pain during backpatching.

Discussion: https://postgr.es/m/ilcctzb5ju2gulvnadjmhgatnkxsdpac652byb2u3d3wqziyvx@fbuqcglker46

Michael's original commit message:

This commit extends the constructor routine of BackgroundPsql.pm with a
new "wait" parameter.  If set to 0, the routine returns without waiting
for psql to start, ready to consume input.

background_psql() in Cluster.pm gains the same "wait" parameter.  The
default behavior is still to wait for psql to start.  It becomes now
possible to not wait, giving to TAP scripts the possibility to perform
actions between a BackgroundPsql startup and its wait_connect() call.

Author: Jacob Champion
Discussion: https://postgr.es/m/CAOYmi+=60deN20WDyCoHCiecgivJxr=98s7s7-C8SkXwrCfHXg@mail.gmail.com
2025-02-19 09:45:09 -05:00
Andres Freund
f4b08ccb4e backport: Improve handling of empty query results in BackgroundPsql
This is a backport of 70291a3c66. Originally it was only applied to master,
but I (Andres) am planning to fix a few bugs in BackgroundPsql that are harder
to fix in the backbranches with the old behavior. It's also generally good for
test infrastructure to behave similarly across branches, to avoid pain during
backpatching.  70291a3c66 changes the behavior in some cases, but after
discussing it, we are ok with that, it seems unlikely that there are
out-of-core tests relying on the prior behavior.

Discussion: https://postgr.es/m/ilcctzb5ju2gulvnadjmhgatnkxsdpac652byb2u3d3wqziyvx@fbuqcglker46

Michael's original commit message:

A newline is not added at the end of an empty query result, causing the
banner of the hardcoded \echo to not be discarded.  This would reflect
on scripts that expect an empty result by showing the "QUERY_SEPARATOR"
in the output returned back to the caller, which was confusing.

This commit changes BackgroundPsql::query() so as empty results are able
to work correctly, making the first newline before the banner optional,
bringing more flexibility.

Note that this change affects 037_invalid_database.pl, where three
queries generated an empty result, with the script relying on the data
from the hardcoded banner to exist in the expected output.  These
queries are changed to use query_safe(), leading to a simpler script.

The author has also proposed a test in a different patch where empty
results would exist when using BackgroundPsql.

Author: Jacob Champion
Reviewed-by: Andrew Dunstan, Michael Paquier
Discussion: https://postgr.es/m/CAOYmi+=60deN20WDyCoHCiecgivJxr=98s7s7-C8SkXwrCfHXg@mail.gmail.com
2025-02-19 09:45:09 -05:00
Michael Paquier
9844eb67cc test_escape: Fix handling of short options in getopt_long()
This addresses two errors in the module, based on the set of options
supported:
- '-c', for --conninfo, was not listed.
- '-f', for --force-unsupported, was not listed.

While on it, these are now listed in an alphabetical order.

Author: Japin Li
Discussion: https://postgr.es/m/ME0P300MB04451FB20CE0346A59C25CADB6FA2@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
Backpatch-through: 13
2025-02-19 09:45:57 +09:00
Andres Freund
22ffbbf24d Fix PQescapeLiteral()/PQescapeIdentifier() length handling
In 5dc1e42b4f I fixed bugs in various escape functions, unfortunately as part
of that I introduced a new bug in PQescapeLiteral()/PQescapeIdentifier(). The
bug is that I made PQescapeInternal() just use strlen(), rather than taking
the specified input length into account.

That's bad, because it can lead to including input that wasn't intended to be
included (in case len is shorter than null termination of the string) and
because it can lead to reading invalid memory if the input string is not null
terminated.

Expand test_escape to this kind of bug:

a) for escape functions with length support, append data that should not be
   escaped and check that it is not

b) add valgrind requests to detect access of bytes that should not be touched

Author: Tom Lane <tgl@sss.pgh.pa.us>
Author: Andres Freund <andres@anarazel.de
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/Z64jD3u46gObCo1p@pryzbyj2023
Backpatch: 13
2025-02-14 18:09:24 -05:00
Michael Paquier
a37c83d1e4 Fix MakeTransitionCaptureState() to return a consistent result
When an UPDATE trigger referencing a new table and a DELETE trigger
referencing an old table are both present, MakeTransitionCaptureState()
returns an inconsistent result for UPDATE commands in its set of flags
and tuplestores holding the TransitionCaptureState for transition
tables.

As proved by the test added here, this issue causes a crash in v14 and
earlier versions (down to 11, actually, older versions do not support
triggers on partitioned tables) during cross-partition updates on a
partitioned table.  v15 and newer versions are safe thanks to
7103ebb7aa.

This commit fixes the function so that it returns a consistent state
by using portions of the changes made in commit 7103ebb7aa for v13 and
v14.  v15 and newer versions are slightly tweaked to match with the
older versions, mainly for consistency across branches.

Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20250207.150238.968446820828052276.horikyota.ntt@gmail.com
Backpatch-through: 13
2025-02-13 16:31:10 +09:00
Andres Freund
a085fa7316 Fix type in test_escape test
On machines where char is unsigned this could lead to option parsing looping
endlessly. It's also too narrow a type on other hardware.

Found via Tom Lane's monitoring of the buildfarm.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Security: CVE-2025-1094
Backpatch-through: 13
2025-02-10 12:12:58 -05:00
Andres Freund
de4b92f333 Add test of various escape functions
As highlighted by the prior commit, writing correct escape functions is less
trivial than one might hope.

This test module tries to verify that different escaping functions behave
reasonably. It e.g. tests:

- Invalidly encoded input to an escape function leads to invalidly encoded
  output

- Trailing incomplete multi-byte characters are handled sensibly

- Escaped strings are parsed as single statement by psql's parser (which
  derives from the backend parser)

There are further tests that would be good to add. But even in the current
state it was rather useful for writing the fix in the prior commit.

Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 13
Security: CVE-2025-1094
2025-02-10 10:03:39 -05:00
Andres Freund
703b3fd5de Add pg_encoding_set_invalid()
There are cases where we cannot / do not want to error out for invalidly
encoded input. In such cases it can be useful to replace e.g. an incomplete
multi-byte characters with bytes that will trigger an error when getting
validated as part of a larger string.

Unfortunately, until now, for some encoding no such sequence existed. For
those encodings this commit removes one previously accepted input combination
- we consider that to be ok, as the chosen bytes are outside of the valid
ranges for the encodings, we just previously failed to detect that.

As we cannot add a new field to pg_wchar_table without breaking ABI, this is
implemented "in-line" in the newly added function.

Author: Noah Misch <noah@leadboat.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Backpatch-through: 13
Security: CVE-2025-1094
2025-02-10 10:03:39 -05:00
Álvaro Herrera
1bc092519b
Fix detach of a partition that has a toplevel FK to a partitioned table
In common cases, foreign keys are defined on the toplevel partitioned
table; but if instead one is defined on a partition and references a
partitioned table, and the referencing partition is detached, we would
examine the pg_constraint row on the partition being detached, and fail
to realize that the sub-constraints must be left alone.  This causes the
ALTER TABLE DETACH process to fail with

 ERROR:  could not find ON INSERT check triggers of foreign key constraint NNN

This is similar but not quite the same as what was fixed by
53af9491a0.  This bug doesn't affect branches earlier than 15, because
the detach procedure was different there, so we only backpatch down to
15.

Fix by skipping such modifying constraints that are children of other
constraints being detached.

Author: Amul Sul <sulamul@gmail.com>
Diagnosys-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b97GuPh6wQPbxQS-Zpy16Oh+0aMv-w64QcGrLhCOZZ6p+g@mail.gmail.com
2025-01-21 14:53:46 +01:00
Tom Lane
8856267284 Avoid using timezone Asia/Manila in regression tests.
The freshly-released 2025a version of tzdata has a refined estimate
for the longitude of Manila, changing their value for LMT in
pre-standardized-timezone days.  This changes the output of one of
our test cases.  Since we need to be able to run with system tzdata
files that may or may not contain this update, we'd better stop
making that specific test.

I switched it to use Asia/Singapore, which has a roughly similar UTC
offset.  That LMT value hasn't changed in tzdb since 2003, so we can
hope that it's well established.

I also noticed that this set of make_timestamptz tests only exercises
zones east of Greenwich, which seems rather sad, and was not the
original intent AFAICS.  (We've already changed these tests once
to stabilize their results across tzdata updates, cf 66b737cd9;
it looks like I failed to consider the UTC-offset-sign aspect then.)
To improve that, add a test with Pacific/Honolulu.  That LMT offset
is also quite old in tzdb, so we'll cross our fingers that it doesn't
get improved.

Reported-by: Christoph Berg <cb@df7cb.de>
Discussion: https://postgr.es/m/Z46inkznCxesvDEb@msg.df7cb.de
Backpatch-through: 13
2025-01-20 15:47:53 -05:00
Michael Paquier
26554faccc Fix header check for continuation records where standbys could be stuck
XLogPageRead() checks immediately for an invalid WAL record header on a
standby, to be able to handle the case of continuation records that need
to be read across two different sources.  As written, the check was too
generic, applying to any target LSN.  Based on an analysis by Kyotaro
Horiguchi, what really matters is to make sure that the page header is
checked when attempting to read a LSN at the boundary of a segment, to
handle the case of a continuation record that spawns across multiple
pages when dealing with multiple segments, as WAL receivers are spawned
they request WAL from the beginning of a segment.  This fix has been
proposed by Kyotaro Horiguchi.

This could cause standbys to loop infinitely when dealing with a
continuation record during a timeline jump, in the case where the
contents of the record in the follow-up page are invalid.

Some regression tests are added to check such scenarios, able to
reproduce the original problem.  In the test, the contents of a
continuation record are overwritten with junk zeros on its follow-up
page, and replayed on standbys.  This is inspired by 039_end_of_wal.pl,
and is enough to show how standbys should react on promotion by not
being stuck.  Without the fix, the test would fail with a timeout.  The
test to reproduce the problem has been written by Alexander Kukushkin.

The original check has been introduced in 0668719801, for a similar
problem.

Author: Kyotaro Horiguchi, Alexander Kukushkin
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAFh8B=mozC+e1wGJq0H=0O65goZju+6ab5AU7DEWCSUA2OtwDg@mail.gmail.com
Backpatch-through: 13
2025-01-20 09:30:37 +09:00
Michael Paquier
42c900d31e Revert recent changes related to handling of 2PC files at recovery
This commit reverts 8f67f994e8 (down to v13) and c3de0f9eed (down to
v17), as these are proving to not be completely correct regarding two
aspects:
- In v17 and newer branches, c3de0f9eed38's check for epoch handling is
incorrect, and does not correctly handle frozen epochs.  A logic closer
to widen_snapshot_xid() should be used.  The 2PC code should try to
integrate deeper with FullTransactionIds, 5a1dfde833 being not enough.
- In v13 and newer branches, 8f67f994e8 is a workaround for the real
issue, which is that we should not attempt CLOG lookups without reaching
consistency.  This exists since 728bd991c3, and this is reachable with
ProcessTwoPhaseBuffer() called by restoreTwoPhaseData() at the beginning
of recovery.

Per discussion with Noah Misch.

Discussion: https://postgr.es/m/20250116010051.f3.nmisch@google.com
Backpatch-through: 13
2025-01-17 13:27:45 +09:00
Tom Lane
724ebebb11 Fix setrefs.c's failure to do expression processing on prune steps.
We should run the expression subtrees of PartitionedRelPruneInfo
structs through fix_scan_expr.  Failure to do so means that
AlternativeSubPlans within those expressions won't be cleaned up
properly, resulting in "unrecognized node type" errors since v14.

It seems fairly likely that at least some of the other steps done
by fix_scan_expr are important here as well, resulting in as-yet-
undetected bugs.  Therefore, I've chosen to back-patch this to
all supported branches including v13, even though the known
symptom doesn't manifest in v13.

Per bug #18778 from Alexander Lakhin.

Discussion: https://postgr.es/m/18778-24cd399df6c806af@postgresql.org
2025-01-16 20:40:07 -05:00
Michael Paquier
e5d113057d Move routines to manipulate WAL into PostgreSQL::Test::Cluster
These facilities were originally in the recovery TAP test
039_end_of_wal.pl.  A follow-up bug fix with a TAP test doing similar
WAL manipulations requires them, and all these had better not be
duplicated due to their complexity.  The routine names are tweaked to
use "wal" more consistently, similarly to the existing "advance_wal".

In v14 and v13, the new routines are moved to PostgresNode.pm.
039_end_of_wal.pl is updated to use the refactored routines, without
changing its coverage.

Reviewed-by: Alexander Kukushkin
Discussion: https://postgr.es/m/CAFh8B=mozC+e1wGJq0H=0O65goZju+6ab5AU7DEWCSUA2OtwDg@mail.gmail.com
Backpatch-through: 13
2025-01-16 09:26:28 +09:00
Dean Rasheed
7c0379516f Fix XMLTABLE() deparsing to quote namespace names if necessary.
When deparsing an XMLTABLE() expression, XML namespace names were not
quoted. However, since they are parsed as ColLabel tokens, some names
require double quotes to ensure that they are properly interpreted.
Fix by using quote_identifier() in the deparsing code.

Back-patch to all supported versions.

Dean Rasheed, reviewed by Tom Lane.

Discussion: https://postgr.es/m/CAEZATCXTpAS%3DncfLNTZ7YS6O5puHeLg_SUYAit%2Bcs7wsrd9Msg%40mail.gmail.com
2025-01-12 12:59:40 +00:00
Michael Paquier
d9ade6f2d4 Fix handling of orphaned 2PC files in the future at recovery
Before 728bd991c3, that has improved the support for 2PC files during
recovery, the initial logic scanning files in pg_twophase was done so as
files in the future of the transaction ID horizon were checked first,
followed by a check if a transaction ID is aborted or committed which
could involve a pg_xact lookup.  After this commit, these checks have
been done in reverse order.

Files detected as in the future do not have a state that can be checked
in pg_xact, hence this caused recovery to fail abruptly should an
orphaned 2PC file in the future of the transaction ID horizon exist in
pg_twophase at the beginning of recovery.

A test is added to check for this scenario, using an empty 2PC with a
transaction ID large enough to be in the future when running the test.
This test is added in 16 and older versions for now.  17 and newer
versions are impacted by a second bug caused by the addition of the
epoch in the 2PC file names.  An equivalent test will be added in these
branches in a follow-up commit, once the second set of issues reported
are fixed.

Author: Vitaly Davydov, Michael Paquier
Discussion: https://postgr.es/m/11e597-676ab680-8d-374f23c0@145466129
Backpatch-through: 13
2024-12-30 08:06:43 +09:00
Noah Misch
83bb523756 In REASSIGN OWNED of a database, lock the tuple as mandated.
Commit aac2c9b4fd mandated such locking
and attempted to fulfill that mandate, but it missed REASSIGN OWNED.
Hence, it remained possible to lose VACUUM's inplace update of
datfrozenxid if a REASSIGN OWNED processed that database at the same
time.  This didn't affect the other inplace-updated catalog, pg_class.
For pg_class, REASSIGN OWNED calls ATExecChangeOwner() instead of the
generic AlterObjectOwner_internal(), and ATExecChangeOwner() fulfills
the locking mandate.

Like in GRANT, implement this by following the locking protocol for any
catalog subject to the generic AlterObjectOwner_internal().  It would
suffice to do this for IsInplaceUpdateOid() catalogs only.  Back-patch
to v13 (all supported versions).

Kirill Reshke.  Reported by Alexander Kukushkin.

Discussion: https://postgr.es/m/CAFh8B=mpKjAy4Cuun-HP-f_vRzh2HSvYFG3rhVfYbfEBUhBAGg@mail.gmail.com
2024-12-28 07:16:26 -08:00
David Rowley
ef178d38bb Fix Assert failure in WITH RECURSIVE UNION queries
If the non-recursive part of a recursive CTE ended up using
TTSOpsBufferHeapTuple as the table slot type, then a duplicate value
could cause an Assert failure in CheckOpSlotCompatibility() when
checking the hash table for the duplicate value.  The expected slot type
for the deform step was TTSOpsMinimalTuple so the Assert failed when the
TTSOpsBufferHeapTuple slot was used.

This is a long-standing bug which we likely didn't notice because it
seems much more likely that the non-recursive term would have required
projection and used a TTSOpsVirtual slot, which CheckOpSlotCompatibility
is ok with.

There doesn't seem to be any harm done here other than the Assert
failure.  Both TTSOpsMinimalTuple and TTSOpsBufferHeapTuple slot types
require tuple deformation, so the EEOP_*_FETCHSOME ExprState step would
have properly existed in the ExprState.

The solution is to pass NULL for the ExecBuildGroupingEqual's 'lops'
parameter.  This means the ExprState's EEOP_*_FETCHSOME step won't
expect a fixed slot type.  This makes CheckOpSlotCompatibility() happy as
no checking is performed when the ExprEvalStep is not expecting a fixed
slot type.

Reported-by: Richard Guo
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAMbWs4-8U9q2LAtf8+ghV11zeUReA3AmrYkxzBEv0vKnDxwkKA@mail.gmail.com
Backpatch-through: 13, all supported versions
2024-12-19 13:13:01 +13:00
Heikki Linnakangas
2af2457fa6 Make 009_twophase.pl test pass with recovery_min_apply_delay set
The test failed if you ran the regression tests with TEMP_CONFIG with
recovery_min_apply_delay = '500ms'. Fix the race condition by waiting
for transaction to be applied in the replica, like in a few other
tests.

The failing test was introduced in commit cbfbda7841. Backpatch to all
supported versions like that commit (except v12, which is no longer
supported).

Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/09e2a70a-a6c2-4b5c-aeae-040a7449c9f2@gmail.com
2024-12-16 15:59:34 +02:00
David Rowley
d54378e984 Fix possible crash during WindowAgg evaluation
When short-circuiting WindowAgg node evaluation on the top-level
WindowAgg node using quals on monotonic window functions, because the
WindowAgg run condition can mean there's no need to evaluate subsequent
window function results in the same partition once the run condition
becomes false, it was possible that the executor would use stale results
from the previous invocation of the window function in some cases.

A fix for this was partially done by a5832722, but that commit only
fixed the issue for non-top-level WindowAgg nodes.  I mistakenly thought
that the top-level WindowAgg didn't have this issue, but Jayesh's example
case clearly shows that's incorrect.  At the time, I also thought that
this only affected 32-bit systems as all window functions which then
supported run conditions returned BIGINT, however, that's wrong as
ExecProject is still called and that could cause evaluation of any other
window function belonging to the same WindowAgg node, one of which may
return a byref type.

The only queries affected by this are WindowAggs with a "Run Condition"
which contains at least one window function with a byref result type,
such as lead() or lag() on a byref column.  The window clause must also
contain a PARTITION BY clause (without a PARTITION BY, execution of the
WindowAgg stops immediately when the run condition becomes false and
there's no risk of using the stale results).

Reported-by: Jayesh Dehankar
Discussion: https://postgr.es/m/193261e2c4d.3dd3cd7c1842.871636075166132237@zohocorp.com
Backpatch-through: 15, where WindowAgg run conditions were added
2024-12-09 14:24:54 +13:00
Tom Lane
d2f59497a3 Fix is_digit labeling of to_timestamp's FFn format codes.
These format codes produce or consume strings of digits, so they
should be labeled with is_digit = true, but they were not.
This has effect in only one place, where is_next_separator()
is checked to see if the preceding format code should slurp up
all the available digits.  Thus, with a format such as '...SSFF3'
with remaining input '12345', the 'SS' code would consume all
five digits (and then complain about seconds being out of range)
when it should eat only two digits.

Per report from Nick Davies.  This bug goes back to d589f9446
where the FFn codes were introduced, so back-patch to v13.

Discussion: https://postgr.es/m/AM8PR08MB6356AC979252CFEA78B56678B6312@AM8PR08MB6356.eurprd08.prod.outlook.com
2024-12-07 13:12:32 -05:00
Tom Lane
80cd33bad1 Fix NULLIF()'s handling of read-write expanded objects.
If passed a read-write expanded object pointer, the EEOP_NULLIF
code would hand that same pointer to the equality function
and then (unless equality was reported) also return the same
pointer as its value.  This is no good, because a function that
receives a read-write expanded object pointer is fully entitled
to scribble on or even delete the object, thus corrupting the
NULLIF output.  (This problem is likely unobservable with the
equality functions provided in core Postgres, but it's easy to
demonstrate with one coded in plpgsql.)

To fix, make sure the pointer passed to the equality function
is read-only.  We can still return the original read-write
pointer as the NULLIF result, allowing optimization of later
operations.

Per bug #18722 from Alexander Lakhin.  This has been wrong
since we invented expanded objects, so back-patch to all
supported branches.

Discussion: https://postgr.es/m/18722-fd9e645448cc78b4@postgresql.org
2024-11-25 18:09:10 -05:00
Noah Misch
941e0c0df2 Avoid "you don't own a lock of type ExclusiveLock" in GRANT TABLESPACE.
This WARNING appeared because SearchSysCacheLocked1() read
cc_relisshared before catcache initialization, when the field is false
unconditionally.  On the basis of reading false there, it constructed a
locktag as though pg_tablespace weren't relisshared.  Only shared
catalogs could be affected, and only GRANT TABLESPACE was affected in
practice.  SearchSysCacheLocked1() callers use one other shared-relation
syscache, DATABASEOID.  DATABASEOID is initialized by the end of
CheckMyDatabase(), making the problem unreachable for pg_database.

Back-patch to v13 (all supported versions).  This has no known impact
before v16, where ExecGrant_common() first appeared.  Earlier branches
avoid trouble by having a separate ExecGrant_Tablespace() that doesn't
use LOCKTAG_TUPLE.  However, leaving this unfixed in v15 could ensnare a
future back-patch of a SearchSysCacheLocked1() call.

Reported by Aya Iwata.

Discussion: https://postgr.es/m/OS7PR01MB11964507B5548245A7EE54E70EA212@OS7PR01MB11964.jpnprd01.prod.outlook.com
2024-11-25 14:42:39 -08:00
Noah Misch
edf80895f6 Fix per-session activation of ALTER {ROLE|DATABASE} SET role.
After commit 5a2fed911a, the catalog state
resulting from these commands ceased to affect sessions.  Restore the
longstanding behavior, which is like beginning the session with a SET
ROLE command.  If cherry-picking the CVE-2024-10978 fixes, default to
including this, too.  (This fixes an unintended side effect of fixing
CVE-2024-10978.)  Back-patch to v12, like that commit.  The release team
decided to include v12, despite the original intent to halt v12 commits
earlier this week.

Tom Lane and Noah Misch.  Reported by Etienne LAFARGE.

Discussion: https://postgr.es/m/CADOZwSb0UsEr4_UTFXC5k7=fyyK8uKXekucd+-uuGjJsGBfxgw@mail.gmail.com
2024-11-15 20:39:59 -08:00
Tom Lane
2496c3f6f1 Avoid assertion due to disconnected NFA sub-graphs in regex parsing.
In commit 08c0d6ad6 which introduced "rainbow" arcs in regex NFAs,
I didn't think terribly hard about what to do when creating the color
complement of a rainbow arc.  Clearly, the complement cannot match any
characters, and I took the easy way out by just not building any arcs
at all in the complement arc set.  That mostly works, but Nikolay
Shaplov found a case where it doesn't: if we decide to delete that
sub-NFA later because it's inside a "{0}" quantifier, delsub()
suffered an assertion failure.  That's because delsub() relies on
the target sub-NFA being fully connected.  That was always true
before, and the best fix seems to be to restore that property.
Hence, invent a new arc type CANTMATCH that can be generated in
place of an empty color complement, and drop it again later when we
start NFA optimization.  (At that point we don't need to do delsub()
any more, and besides there are other cases where NFA optimization can
lead to disconnected subgraphs.)

It appears that this bug has no consequences in a non-assert-enabled
build: there will be some transiently leaked NFA states/arcs, but
they'll get cleaned up eventually.  Still, we don't like assertion
failures, so back-patch to v14 where rainbow arcs were introduced.

Per bug #18708 from Nikolay Shaplov.

Discussion: https://postgr.es/m/18708-f94f2599c9d2c005@postgresql.org
2024-11-15 18:23:38 -05:00
Tom Lane
a5d2e6205f Fix improper interactions between session_authorization and role.
The SQL spec mandates that SET SESSION AUTHORIZATION implies
SET ROLE NONE.  We tried to implement that within the lowest-level
functions that manipulate these settings, but that was a bad idea.
In particular, guc.c assumes that it doesn't matter in what order
it applies GUC variable updates, but that was not the case for these
two variables.  This problem, compounded by some hackish attempts to
work around it, led to some security-grade issues:

* Rolling back a transaction that had done SET SESSION AUTHORIZATION
would revert to SET ROLE NONE, even if that had not been the previous
state, so that the effective user ID might now be different from what
it had been.

* The same for SET SESSION AUTHORIZATION in a function SET clause.

* If a parallel worker inspected current_setting('role'), it saw
"none" even when it should see something else.

Also, although the parallel worker startup code intended to cope
with the current role's pg_authid row having disappeared, its
implementation of that was incomplete so it would still fail.

Fix by fully separating the miscinit.c functions that assign
session_authorization from those that assign role.  To implement the
spec's requirement, teach set_config_option itself to perform "SET
ROLE NONE" when it sets session_authorization.  (This is undoubtedly
ugly, but the alternatives seem worse.  In particular, there's no way
to do it within assign_session_authorization without incompatible
changes in the API for GUC assign hooks.)  Also, improve
ParallelWorkerMain to directly set all the relevant user-ID variables
instead of relying on some of them to get set indirectly.  That
allows us to survive not finding the pg_authid row during worker
startup.

In v16 and earlier, this includes back-patching 9987a7bf3 which
fixed a violation of GUC coding rules: SetSessionAuthorization
is not an appropriate place to be throwing errors from.

Security: CVE-2024-10978
2024-11-11 10:29:54 -05:00
Nathan Bossart
6db5ea8de8 Ensure cached plans are correctly marked as dependent on role.
If a CTE, subquery, sublink, security invoker view, or coercion
projection references a table with row-level security policies, we
neglected to mark the plan as potentially dependent on which role
is executing it.  This could lead to later executions in the same
session returning or hiding rows that should have been hidden or
returned instead.

Reported-by: Wolfgang Walther
Reviewed-by: Noah Misch
Security: CVE-2024-10976
Backpatch-through: 12
2024-11-11 09:00:00 -06:00
Noah Misch
e530835c6c Block environment variable mutations from trusted PL/Perl.
Many process environment variables (e.g. PATH), bypass the containment
expected of a trusted PL.  Hence, trusted PLs must not offer features
that achieve setenv().  Otherwise, an attacker having USAGE privilege on
the language often can achieve arbitrary code execution, even if the
attacker lacks a database server operating system user.

To fix PL/Perl, replace trusted PL/Perl %ENV with a tied hash that just
replaces each modification attempt with a warning.  Sites that reach
these warnings should evaluate the application-specific implications of
proceeding without the environment modification:

  Can the application reasonably proceed without the modification?

    If no, switch to plperlu or another approach.

    If yes, the application should change the code to stop attempting
    environment modifications.  If that's too difficult, add "untie
    %main::ENV" in any code executed before the warning.  For example,
    one might add it to the start of the affected function or even to
    the plperl.on_plperl_init setting.

In passing, link to Perl's guidance about the Perl features behind the
security posture of PL/Perl.

Back-patch to v12 (all supported versions).

Andrew Dunstan and Noah Misch

Security: CVE-2024-10979
2024-11-11 06:23:47 -08:00
Amit Langote
33040b1715 Disallow partitionwise join when collations don't match
If the collation of any join key column doesn’t match the collation of
the corresponding partition key, partitionwise joins can yield incorrect
results. For example, rows that would match under the join key collation
might be located in different partitions due to the partitioning
collation. In such cases, a partitionwise join would yield different
results from a non-partitionwise join, so disallow it in such cases.

Reported-by: Tender Wang <tndrwang@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com
Backpatch-through: 12
2024-11-08 17:18:55 +09:00
Amit Langote
0a620659c5 Disallow partitionwise grouping when collations don't match
If the collation of any grouping column doesn’t match the collation of
the corresponding partition key, partitionwise grouping can yield
incorrect results. For example, rows that would be grouped under the
grouping collation may end up in different partitions under the
partitioning collation. In such cases, full partitionwise grouping
would produce results that differ from those without partitionwise
grouping, so disallowed that.

Partial partitionwise aggregation is still allowed, as the Finalize
step reconciles partition-level aggregates with grouping requirements
across all partitions, ensuring that the final output remains
consistent.

This commit also fixes group_by_has_partkey() by ensuring the
RelabelType node is stripped from grouping expressions when matching
them to partition key expressions to avoid false mismatches.

Bug: #18568
Reported-by: Webbo Han <1105066510@qq.com>
Author: Webbo Han <1105066510@qq.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/18568-2a9afb6b9f7e6ed3@postgresql.org
Discussion: https://postgr.es/m/tencent_9D9103CDA420C07768349CC1DFF88465F90A@qq.com
Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com
Backpatch-through: 12
2024-11-08 16:06:58 +09:00
Peter Eisentraut
38f506470f Message style improvement
Backpatch the part of edee0c621d that applies to a90bdd7a44, which
was also backpatched.  That way, the message is consistent in all
branches.
2024-11-08 07:31:48 +01:00
Noah Misch
27642d8908 Revert "For inplace update, send nontransactional invalidations."
This reverts commit 95c5acb3fc (v17) and
counterparts in each other non-master branch.  If released, that commit
would have caused a worst-in-years minor release regression, via
undetected LWLock self-deadlock.  This commit and its self-deadlock fix
warrant more bake time in the master branch.

Reported by Alexander Lakhin.

Discussion: https://postgr.es/m/10ec0bc3-5933-1189-6bb8-5dec4114558e@gmail.com
2024-11-02 09:05:04 -07:00
Álvaro Herrera
1b216fceff
Fix some more bugs in foreign keys connecting partitioned tables
* In DetachPartitionFinalize() we were applying a tuple conversion map
  to tuples that didn't need one, which can lead to erratic behavior if
  a partitioned table has a partition with a different column order, as
  reported by Alexander Lakhin. This was introduced by 53af9491a0.
  Don't do that.  Also, modify a recently added test case to exercise
  this.

* The same function as well as CloneFkReferenced() were acquiring
  AccessShareLock on a partition, only to have CreateTrigger() later
  acquire ShareRowExclusiveLock on it.  This can lead to deadlock by
  lock escalation, unnecessarily.  Avoid that by acquiring the stronger
  lock to begin with.  This probably dates back to branch 12, but I have
  never seen a report of this being a problem in the field.

* Innocuous but wasteful: also introduced by 53af9491a0, we were
  reading a pg_constraint tuple from syscache that we don't need, as
  reported by Tender Wang.  Don't.

Backpatch to 15.

Discussion: https://postgr.es/m/461e9c26-2076-8224-e119-84998b6a784e@gmail.com
2024-10-30 10:54:03 +01:00
Noah Misch
4eac5a1fa7 For inplace update, send nontransactional invalidations.
The inplace update survives ROLLBACK.  The inval didn't, so another
backend's DDL could then update the row without incorporating the
inplace update.  In the test this fixes, a mix of CREATE INDEX and ALTER
TABLE resulted in a table with an index, yet relhasindex=f.  That is a
source of index corruption.  Back-patch to v12 (all supported versions).
The back branch versions don't change WAL, because those branches just
added end-of-recovery SIResetAll().  All branches change the ABI of
extern function PrepareToInvalidateCacheTuple().  No PGXN extension
calls that, and there's no apparent use case in extensions.

Reviewed by Nitin Motiani and (in earlier versions) Andres Freund.

Discussion: https://postgr.es/m/20240523000548.58.nmisch@google.com
2024-10-25 06:51:07 -07:00
Noah Misch
d34ffbaa10 Stop reading uninitialized memory in heap_inplace_lock().
Stop computing a never-used value.  This removes the read; the read had
no functional implications.  Back-patch to v12, like commit
a07e03fd8f.

Reported by Alexander Lakhin.

Discussion: https://postgr.es/m/6c92f59b-f5bc-e58c-9bdd-d1f21c17c786@gmail.com
2024-10-24 09:16:18 -07:00
Álvaro Herrera
5d83bad6b8
Restructure foreign key handling code for ATTACH/DETACH
... to fix bugs when the referenced table is partitioned.

The catalog representation we chose for foreign keys connecting
partitioned tables (in commit f56f8f8da6) is inconvenient, in the
sense that a standalone table has a different way to represent the
constraint when referencing a partitioned table, than when the same
table becomes a partition (and vice versa).  Because of this, we need to
create additional catalog rows on detach (pg_constraint and pg_trigger),
and remove them on attach.  We were doing some of those things, but not
all of them, leading to missing catalog rows in certain cases.

The worst problem seems to be that we are missing action triggers after
detaching a partition, which means that you could update/delete rows
from the referenced partitioned table that still had referencing rows on
that table, the server failing to throw the required errors.

!!!
Note that this means existing databases with FKs that reference
partitioned tables might have rows that break relational integrity, on
tables that were once partitions on the referencing side of the FK.

Another possible problem is that trying to reattach a table
that had been detached would fail indicating that internal triggers
cannot be found, which from the user's point of view is nonsensical.

In branches 15 and above, we fix this by creating a new helper function
addFkConstraint() which is in charge of creating a standalone
pg_constraint row, and repurposing addFkRecurseReferencing() and
addFkRecurseReferenced() so that they're only the recursive routine for
each side of the FK, and they call addFkConstraint() to create
pg_constraint at each partitioning level and add the necessary triggers.
These new routines can be used during partition creation, partition
attach and detach, and foreign key creation.  This reduces redundant
code and simplifies the flow.

In branches 14 and 13, we have a much simpler fix that consists on
simply removing the constraint on detach.  The reason is that those
branches are missing commit f4566345cf, which reworked the way this
works in a way that we didn't consider back-patchable at the time.

We opted to leave branch 12 alone, because it's different from branch 13
enough that the fix doesn't apply; and because it is going in EOL mode
very soon, patching it now might be worse since there's no way to undo
the damage if it goes wrong.

Existing databases might need to be repaired.

In the future we might want to rethink the catalog representation to
avoid this problem, but for now the code seems to do what's required to
make the constraints operate correctly.

Co-authored-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Co-authored-by: Tender Wang <tndrwang@gmail.com>
Co-authored-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Guillaume Lelarge <guillaume@lelarge.info>
Reported-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Reported-by: Thomas Baehler (SBB CFF FFS) <thomas.baehler2@sbb.ch>
Discussion: https://postgr.es/m/20230420144344.40744130@karst
Discussion: https://postgr.es/m/20230705233028.2f554f73@karst
Discussion: https://postgr.es/m/GVAP278MB02787E7134FD691861635A8BC9032@GVAP278MB0278.CHEP278.PROD.OUTLOOK.COM
Discussion: https://postgr.es/m/18541-628a61bc267cd2d3@postgresql.org
2024-10-22 16:01:18 +02:00
Tom Lane
c80a1e0483 Fix wrong assertion and poor error messages in "COPY (query) TO".
If the query is rewritten into a NOTIFY command by a DO INSTEAD
rule, we'd get an assertion failure, or in non-assert builds
issue a rather confusing error message.  Improve that.

Also fix a longstanding grammar mistake in a nearby error message.

Per bug #18664 from Alexander Lakhin.  Back-patch to all supported
branches.

Tender Wang and Tom Lane

Discussion: https://postgr.es/m/18664-ffd0ebc2386598df@postgresql.org
2024-10-21 15:08:22 -04:00