Commit Graph

50087 Commits

Author SHA1 Message Date
Tom Lane
805093113d First-draft release notes for 13.2.
As usual, the release notes for other branches will be made by cutting
these down, but put them up for community review first.
2021-02-05 15:05:06 -05:00
Heikki Linnakangas
c87cbd51ee Fix backslash-escaping multibyte chars in COPY FROM.
If a multi-byte character is escaped with a backslash in TEXT mode input,
and the encoding is one of the client-only encodings where the bytes after
the first one can have an ASCII byte "embedded" in the char, we didn't
skip the character correctly. After a backslash, we only skipped the first
byte of the next character, so if it was a multi-byte character, we would
try to process its second byte as if it was a separate character. If it
was one of the characters with special meaning, like '\n', '\r', or
another '\\', that would cause trouble.

One such exmple is the byte sequence '\x5ca45c2e666f6f' in Big5 encoding.
That's supposed to be [backslash][two-byte character][.][f][o][o], but
because the second byte of the two-byte character is 0x5c, we incorrectly
treat it as another backslash. And because the next character is a dot, we
parse it as end-of-copy marker, and throw an "end-of-copy marker corrupt"
error.

Backpatch to all supported versions.

Reviewed-by: John Naylor, Kyotaro Horiguchi
Discussion: https://www.postgresql.org/message-id/a897f84f-8dca-8798-3139-07da5bb38728%40iki.fi
2021-02-05 11:19:48 +02:00
Etsuro Fujita
984384129b postgres_fdw: Fix assertion in estimate_path_cost_size().
Commit 08d2d58a2 added an assertion assuming that the retrieved_rows
estimate for a foreign relation, which is re-used to cost pre-sorted
foreign paths with local stats, is set to at least one row in
estimate_path_cost_size(), which isn't correct because if the relation
is a foreign table with tuples=0, the estimate would be set to 0 there
when not using remote estimates.

Per bug #16807 from Alexander Lakhin.  Back-patch to v13 where the
aforementioned commit went in.

Author: Etsuro Fujita
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/16807-9fe4e08fbaa5c7ce%40postgresql.org
2021-02-05 15:30:02 +09:00
Tom Lane
6467661b6d Fix bug in HashAgg's selective-column-spilling logic.
Commit 230230223 taught nodeAgg.c that, when spilling tuples from
memory in an oversized hash aggregation, it only needed to spill
input columns referenced in the node's tlist and quals.  Unfortunately,
that's wrong: we also have to save the grouping columns.  The error
is masked in common cases because the grouping columns also appear
in the tlist, but that's not necessarily true.  The main category
of plans where it's not true seem to come from semijoins ("WHERE
outercol IN (SELECT innercol FROM innertable)") where the innercol
needs an implicit promotion to make it comparable to the outercol.
The grouping column will be "innercol::promotedtype", but that
expression appears nowhere in the Agg node's own tlist and quals;
only the bare "innercol" is found in the tlist.

I spent quite a bit of time looking for a suitable regression test
case for this, without much success.  If the number of distinct
values of the innercol is large enough to make spilling happen,
the planner tends to prefer a non-HashAgg plan, at least for
problem sizes that are reasonable to use in the regression tests.
So, no new regression test.  However, this patch does demonstrably
fix the originally-reported test case.

Per report from s.p.e (at) gmx-topmail.de.  Backpatch to v13
where the troublesome code came in.

Discussion: https://postgr.es/m/trinity-1c565d44-159f-488b-a518-caf13883134f-1611835701633@3c-app-gmx-bap78
2021-02-04 23:01:33 -05:00
Tom Lane
10fcb83da6 Fix YA incremental sort bug.
switchToPresortedPrefixMode() did the wrong thing if it detected
a batch boundary just at the last tuple of a fullsort group.

The initially-reported symptom was a "retrieved too many tuples in a
bounded sort" error, but the test case added here just silently gives
the wrong answer without this patch.

I (tgl) am not really happy about committing this patch without review
from the incremental-sort authors, but they seem AWOL and we are hard
against a release deadline.  This does demonstrably make some cases
better, anyway.

Per bug #16846 from Yoran Heling.  Back-patch to v13 where incremental
sort was introduced.

Neil Chen

Discussion: https://postgr.es/m/16846-ae49f51ac379a4cb@postgresql.org
2021-02-04 19:12:09 -05:00
Tom Lane
57868d957e Avoid crash when rolling back within a prepared statement.
If a portal is used to run a prepared CALL or DO statement that
contains a ROLLBACK, PortalRunMulti fails because the portal's
statement list gets cleared by the rollback.  (Since the grammar
doesn't allow CALL/DO in PREPARE, the only easy way to get to this is
via extended query protocol, which treats all inputs as prepared
statements.)  It's difficult to avoid resetting the portal early
because of resource-management issues, so work around this by teaching
PortalRunMulti to be wary of portal->stmts having suddenly become NIL.

The crash has only been seen to occur in v13 and HEAD (as a
consequence of commit 1cff1b95a having added an extra touch of
portal->stmts).  But even before that, the code involved touching a
List that the portal no longer has any claim on.  In the test case at
hand, the List will still exist because of another refcount on the
cached plan; but I'm far from convinced that it's impossible for the
cached plan to have been dropped by the time control gets back to
PortalRunMulti.  Hence, backpatch to v11 where nested transactions
were added.

Thomas Munro and Tom Lane, per bug #16811 from James Inform

Discussion: https://postgr.es/m/16811-c1b599b2c6c2d622@postgresql.org
2021-02-03 19:38:29 -05:00
Peter Eisentraut
1d3ce0223c pg_dump: Fix dumping of inherited generated columns
Generation expressions of generated columns are always inherited, so
there is no need to set them separately in child tables, and there is
no syntax to do so either.  The code previously used the code paths
for the handling of default values, for which different rules apply;
in particular it might want to set a default value explicitly for an
inherited column.  This resulted in unrestorable dumps.  For generated
columns, just skip them in inherited tables.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/15830.1575468847%40sss.pgh.pa.us
2021-02-03 11:43:01 +01:00
Tom Lane
0fe8b1f7d4 Remove extra increment of plpgsql's statement counter for FOR loops.
This left gaps in the internal statement numbering, which is not
terribly harmful (else we'd have noticed sooner), but it's not
great either.

Oversight in bbd5c207b; backpatch to v12 where that came in.

Pavel Stehule

Discussion: https://postgr.es/m/CAFj8pRDXyQaJmpotNTQVc-t-WxdWZC35V2PnmwOaV1-taidFWA@mail.gmail.com
2021-02-02 14:35:20 -05:00
Tom Lane
5868913943 Fix ancient memory leak in contrib/auto_explain.
The ExecutorEnd hook is invoked in a context that could be quite
long-lived, not the executor's own per-query context as I think
we were sort of assuming.  Thus, any cruft generated while producing
the EXPLAIN output could accumulate over multiple queries.  This can
result in spectacular leakage if log_nested_statements is on, and
even without that I'm surprised nobody complained before.

To fix, just switch into the executor's context so that anything we
allocate will be released when standard_ExecutorEnd frees the executor
state.  We might as well nuke the code's retail pfree of the explain
output string, too; that's laughably inadequate to the need.

Japin Li, per report from Jeff Janes.  This bug is old, so
back-patch to all supported branches.

Discussion: https://postgr.es/m/CAMkU=1wCVtbeRn0s9gt12KwQ7PLXovbpM8eg25SYocKW3BT4hg@mail.gmail.com
2021-02-02 13:49:08 -05:00
Tom Lane
dae5af6c19 Doc: work a little harder on the initial examples for regex matching.
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
2021-02-01 16:38:52 -05:00
Noah Misch
d798ea750d Revive "snapshot too old" with wal_level=minimal and SET TABLESPACE.
Given a permanent relation rewritten in the current transaction, the
old_snapshot_threshold mechanism assumed the relation had never been
subject to early pruning.  Hence, a query could fail to report "snapshot
too old" when the rewrite followed an early truncation.  ALTER TABLE SET
TABLESPACE is probably the only rewrite mechanism capable of exposing
this bug.  REINDEX sets indcheckxmin, avoiding the problem.  CLUSTER has
zeroed page LSNs since before old_snapshot_threshold existed, so
old_snapshot_threshold has never cooperated with it.  ALTER TABLE
... SET DATA TYPE makes the table look empty to every past snapshot,
which is strictly worse.  Back-patch to v13, where commit
c6b92041d3 broke this.

Kyotaro Horiguchi and Noah Misch

Discussion: https://postgr.es/m/20210113.160705.2225256954956139776.horikyota.ntt@gmail.com
2021-01-30 00:13:58 -08:00
Noah Misch
e8e3e67490 Fix error with CREATE PUBLICATION, wal_level=minimal, and new tables.
CREATE PUBLICATION has failed spuriously when applied to a permanent
relation created or rewritten in the current transaction.  Make the same
change to another site having the same semantic intent; the second
instance has no user-visible consequences.  Back-patch to v13, where
commit c6b92041d3 broke this.

Kyotaro Horiguchi

Discussion: https://postgr.es/m/20210113.160705.2225256954956139776.horikyota.ntt@gmail.com
2021-01-30 00:12:05 -08:00
Noah Misch
86a5b309c9 Fix CREATE INDEX CONCURRENTLY for simultaneous prepared transactions.
In a cluster having used CREATE INDEX CONCURRENTLY while having enabled
prepared transactions, queries that use the resulting index can silently
fail to find rows.  Fix this for future CREATE INDEX CONCURRENTLY by
making it wait for prepared transactions like it waits for ordinary
transactions.  This expands the VirtualTransactionId structure domain to
admit prepared transactions.  It may be necessary to reindex to recover
from past occurrences.  Back-patch to 9.5 (all supported versions).

Andrey Borodin, reviewed (in earlier versions) by Tom Lane and Michael
Paquier.

Discussion: https://postgr.es/m/2E712143-97F7-4890-B470-4A35142ABC82@yandex-team.ru
2021-01-30 00:00:42 -08:00
Tom Lane
2a01bc275b Doc: improve cross-references for SET/SHOW.
The corresponding functions set_config and current_setting were
mostly not hyperlinked.  Clarify their descriptions a tad, too.

Discussion: https://postgr.es/m/161183356250.4077.687338658090583892@wrigleys.postgresql.org
2021-01-29 10:46:14 -05:00
Alexander Korotkov
9915fe2296 Document behavior of the .** jsonpath accessor in the lax mode
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
2021-01-29 15:28:14 +03:00
Tom Lane
4a9ce085ab Silence another gcc 11 warning.
Per buildfarm and local experimentation, bleeding-edge gcc isn't
convinced that the MemSet in reorder_function_arguments() is safe.
Shut it up by adding an explicit check that pronargs isn't negative,
and by changing MemSet to memset.  (It appears that either change is
enough to quiet the warning at -O2, but let's do both to be sure.)
2021-01-28 17:19:17 -05:00
Alvaro Herrera
16f69062e5
Remove bogus restriction from BEFORE UPDATE triggers
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
2021-01-28 16:56:07 -03:00
Tom Lane
7f1921cb92 Fix hash partition pruning with asymmetric partition sets.
perform_pruning_combine_step() was not taught about the number of
partition indexes used in hash partitioning; more embarrassingly,
get_matching_hash_bounds() also had it wrong.  These errors are masked
in the common case where all the partitions have the same modulus
and no partition is missing.  However, with missing or unequal-size
partitions, we could erroneously prune some partitions that need
to be scanned, leading to silently wrong query answers.

While a minimal-footprint fix for this could be to export
get_partition_bound_num_indexes and make the incorrect functions use it,
I'm of the opinion that that function should never have existed in the
first place.  It's not reasonable data structure design that
PartitionBoundInfoData lacks any explicit record of the length of
its indexes[] array.  Perhaps that was all right when it could always
be assumed equal to ndatums, but something should have been done about
it as soon as that stopped being true.  Putting in an explicit
"nindexes" field makes both partition_bounds_equal() and
partition_bounds_copy() simpler, safer, and faster than before,
and removes explicit knowledge of the number-of-partition-indexes
rules from some other places too.

This change also makes get_hash_partition_greatest_modulus obsolete.
I left that in place in case any external code uses it, but no core
code does anymore.

Per bug #16840 from Michał Albrycht.  Back-patch to v11 where the
hash partitioning code came in.  (In the back branches, add the new
field at the end of PartitionBoundInfoData to minimize ABI risks.)

Discussion: https://postgr.es/m/16840-571a22976f829ad4@postgresql.org
2021-01-28 13:41:55 -05:00
Tom Lane
1449770d31 Make ecpg's rjulmdy() and rmdyjul() agree with their declarations.
We had "short *mdy" in the extern declarations, but "short mdy[3]"
in the actual function definitions.  Per C99 these are equivalent,
but recent versions of gcc have started to issue warnings about
the inconsistency.  Clean it up before the warnings get any more
widespread.

Back-patch, in case anyone wants to build older PG versions with
bleeding-edge compilers.

Discussion: https://postgr.es/m/2401575.1611764534@sss.pgh.pa.us
2021-01-28 11:17:28 -05:00
Alvaro Herrera
ef2a83323c
pgbench: Remove dead code
doConnect() never returns connections in state CONNECTION_BAD, so
checking for that is pointless.  Remove the code that does.

This code has been dead since ba708ea3dc, 20 years ago.

Discussion: https://postgr.es/m/20210126195224.GA20361@alvherre.pgsql
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2021-01-28 12:53:10 -03:00
Andrew Gierth
75e3cca42d Don't add bailout adjustment for non-strict deserialize calls.
When building aggregate expression steps, strict checks need a bailout
jump for when a null value is encountered, so there is a list of steps
that require later adjustment. Adding entries to that list for steps
that aren't actually strict would be harmless, except that there is an
Assert which catches them. This leads to spurious errors on asserts
builds, for data sets that trigger parallel aggregation of an
aggregate with a non-strict deserialization function (no such
aggregates exist in the core system).

Repair by not adding the adjustment entry when it's not needed.

Backpatch back to 11 where the code was introduced.

Per a report from Darafei (Komzpa) of the PostGIS project; analysis
and patch by me.

Discussion: https://postgr.es/m/87mty7peb3.fsf@news-spur.riddles.org.uk
2021-01-28 11:09:40 +00:00
Tom Lane
bfda0a0244 Doc: improve documentation for UNNEST().
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
2021-01-27 12:50:17 -05:00
Michael Paquier
2378d9232e doc: Remove reference to views for TRUNCATE privilege
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
2021-01-27 13:41:03 +09:00
Alvaro Herrera
f17e8f33f7
Report the true database name on connection errors
When reporting connection errors, we might show a database name in the
message that's not the one we actually tried to connect to, if the
database was taken from libpq defaults instead of from user parameters.
Fix such error messages to use PQdb(), which reports the correct name.

(But, per commit 2930c05634, make sure not to try to print NULL.)

Apply to branches 9.5 through 13.  Branch master has already been
changed differently by commit 58cd8dca3d.

Reported-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA+TgmobssJ6rS22dspWnu-oDxXevGmhMD8VcRBjmj-b9UDqRjw@mail.gmail.com
2021-01-26 16:42:13 -03:00
Tom Lane
64bdb6e5f8 Code review for psql's helpSQL() function.
The loops to identify word boundaries could access past the end of
the input string.  Likely that would never result in an actual
crash, but it makes valgrind unhappy.

The logic to try different numbers of words didn't work when the
input has two words but we only have a match to the first, eg
"\h with select".  (We must "continue" the pass loop, not "break".)

The logic to compute nl_count was bizarrely managed, and in at
least two code paths could end up calling PageOutput with
nl_count = 0, resulting in failing to paginate output that should
have been fed to the pager.  Also, in v12 and up, the nl_count
calculation hadn't been updated to account for the addition of a URL.

The PQExpBuffer holding the command syntax details wasn't freed,
resulting in a session-lifespan memory leak.

While here, improve some comments, choose a more descriptive name
for a variable, fix inconsistent datatype choice for another variable.

Per bug #16837 from Alexander Lakhin.  This code is very old,
so back-patch to all supported branches.

Kyotaro Horiguchi and Tom Lane

Discussion: https://postgr.es/m/16837-479bcd56040c71b3@postgresql.org
2021-01-26 13:04:52 -05:00
Tom Lane
366d302d14 Don't clobber the calling user's credentials cache in Kerberos test.
Embarrassing oversight in this test script, which fortunately is not
run by default.

Report and patch by Jacob Champion.

Discussion: https://postgr.es/m/1fcb175bafef6560f47a8c31229fa7c938486b8d.camel@vmware.com
2021-01-25 14:53:13 -05:00
Tom Lane
a26194f22b Fix broken ruleutils support for function TRANSFORM clauses.
I chanced to notice that this dumped core due to a faulty Assert.
To add insult to injury, the output has been misformatted since v11.
Obviously we need some regression testing here.

Discussion: https://postgr.es/m/d1cc628c-3953-4209-957b-29427acc38c8@www.fastmail.com
2021-01-25 13:03:11 -05:00
Tom Lane
652f7818bf Doc: improve documentation of pg_proc.protrftypes.
Add a "references" link pointing to pg_type, as we have for other arrays
of type OIDs.  Wordsmith the explanation a bit.

Joel Jacobson, additional editing by me

Discussion: https://postgr.es/m/d1cc628c-3953-4209-957b-29427acc38c8@www.fastmail.com
2021-01-25 11:20:17 -05:00
David Rowley
7632ef5a71 Fix hypothetical bug in heap backward scans
Both heapgettup() and heapgettup_pagemode() incorrectly set the first page
to scan in a backward scan in which the number of pages to scan was
specified by heap_setscanlimits().  The code incorrectly started the scan
at the end of the relation when startBlk was 0, or otherwise at
startBlk - 1, neither of which is correct when only scanning a subset of
pages.

The fix here checks if heap_setscanlimits() has changed the number of
pages to scan and if so we set the first page to scan as the final page in
the specified range during backward scans.

Proper adjustment of this code was forgotten when heap_setscanlimits() was
added in 7516f5259 back in 9.5.  However, practice, nowhere in core code
performs backward scans after having used heap_setscanlimits(), yet, it is
possible an extension uses the heap functions in this way, hence
backpatch.

An upcoming patch does use heap_setscanlimits() with backward scans, so
this must be fixed before that can go in.

Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvpGc9h0_oVD2CtgBcxCS1N-qDYZSeBRnUh+0CWJA9cMaA@mail.gmail.com
Backpatch-through: 9.5, all supported versions
2021-01-25 19:52:52 +13:00
Tom Lane
58a5453441 Update time zone data files to tzdata release 2021a.
DST law changes in Russia (Volgograd zone) and South Sudan.
Historical corrections for Australia, Bahamas, Belize, Bermuda,
Ghana, Israel, Kenya, Nigeria, Palestine, Seychelles, and Vanuatu.
Notably, the Australia/Currie zone has been corrected to the point
where it is identical to Australia/Hobart.
2021-01-24 16:29:47 -05:00
Tom Lane
8fe8a5539e Doc: improve directions for building on macOS.
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
2021-01-22 18:58:40 -05:00
Tom Lane
35a7eef08a Doc: remove misleading claim in documentation of PQreset().
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
2021-01-22 11:29:52 -05:00
Tom Lane
73fc2e5bab Fix pull_varnos' miscomputation of relids set for a PlaceHolderVar.
Previously, pull_varnos() took the relids of a PlaceHolderVar as being
equal to the relids in its contents, but that fails to account for the
possibility that we have to postpone evaluation of the PHV due to outer
joins.  This could result in a malformed plan.  The known cases end up
triggering the "failed to assign all NestLoopParams to plan nodes"
sanity check in createplan.c, but other symptoms may be possible.

The right value to use is the join level we actually intend to evaluate
the PHV at.  We can get that from the ph_eval_at field of the associated
PlaceHolderInfo.  However, there are some places that call pull_varnos()
before the PlaceHolderInfos have been created; in that case, fall back
to the conservative assumption that the PHV will be evaluated at its
syntactic level.  (In principle this might result in missing some legal
optimization, but I'm not aware of any cases where it's an issue in
practice.)  Things are also a bit ticklish for calls occurring during
deconstruct_jointree(), but AFAICS the ph_eval_at fields should have
reached their final values by the time we need them.

The main problem in making this work is that pull_varnos() has no
way to get at the PlaceHolderInfos.  We can fix that easily, if a
bit tediously, in HEAD by passing it the planner "root" pointer.
In the back branches that'd cause an unacceptable API/ABI break for
extensions, so leave the existing entry points alone and add new ones
with the additional parameter.  (If an old entry point is called and
encounters a PHV, it'll fall back to using the syntactic level,
again possibly missing some valid optimization.)

Back-patch to v12.  The computation is surely also wrong before that,
but it appears that we cannot reach a bad plan thanks to join order
restrictions imposed on the subquery that the PlaceHolderVar came from.
The error only became reachable when commit 4be058fe9 allowed trivial
subqueries to be collapsed out completely, eliminating their join order
restrictions.

Per report from Stephan Springl.

Discussion: https://postgr.es/m/171041.1610849523@sss.pgh.pa.us
2021-01-21 15:37:23 -05:00
Tom Lane
6671e81946 Further tweaking of PG_SYSROOT heuristics for macOS.
It emerges that in some phases of the moon (perhaps to do with
directory entry order?), xcrun will report that the SDK path is
  /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk
which is normally a symlink to a version-numbered sibling directory.
Our heuristic to skip non-version-numbered pathnames was rejecting
that, which is the wrong thing to do.  We'd still like to end up
with a version-numbered PG_SYSROOT value, but we can have that by
dereferencing the symlink.

Like the previous fix, back-patch to all supported versions.

Discussion: https://postgr.es/m/522433.1611089678@sss.pgh.pa.us
2021-01-20 12:07:31 -05:00
Tom Lane
a57dbfcda5 Disable vacuum page skipping in selected test cases.
By default VACUUM will skip pages that it can't immediately get
exclusive access to, which means that even activities as harmless
and unpredictable as checkpoint buffer writes might prevent a page
from being processed.  Ordinarily this is no big deal, but we have
a small number of test cases that examine the results of VACUUM's
processing and therefore will fail if the page of interest is skipped.
This seems to be the explanation for some rare buildfarm failures.
To fix, add the DISABLE_PAGE_SKIPPING option to the VACUUM commands
in tests where this could be an issue.

In passing, remove a duplicated query in pageinspect/sql/page.sql.

Back-patch as necessary (some of these cases are as old as v10).

Discussion: https://postgr.es/m/413923.1611006484@sss.pgh.pa.us
2021-01-20 11:49:29 -05:00
Heikki Linnakangas
b8403d140f Fix bug in detecting concurrent page splits in GiST insert
In commit 9eb5607e69, I got the condition on checking for split or
deleted page wrong: I used && instead of ||. The comment correctly said
"concurrent split _or_ deletion".

As a result, GiST insertion could miss a concurrent split, and insert to
wrong page. Duncan Sands demonstrated this with a test script that did a
lot of concurrent inserts.

Backpatch to v12, where this was introduced. REINDEX is required to fix
indexes that were affected by this bug.

Backpatch-through: 12
Reported-by: Duncan Sands
Discussion: https://www.postgresql.org/message-id/a9690483-6c6c-3c82-c8ba-dc1a40848f11%40deepbluecap.com
2021-01-20 11:58:25 +02:00
Michael Paquier
31e0f9d76b Fix ALTER DEFAULT PRIVILEGES with duplicated objects
Specifying duplicated objects in this command would lead to unique
constraint violations in pg_default_acl or "tuple already updated by
self" errors.  Similarly to GRANT/REVOKE, increment the command ID after
each subcommand processing to allow this case to work transparently.

A regression test is added by tweaking one of the existing queries of
privileges.sql to stress this case.

Reported-by: Andrus
Author: Michael Paquier
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/ae2a7dc1-9d71-8cba-3bb9-e4cb7eb1f44e@hot.ee
Backpatch-through: 9.5
2021-01-20 11:39:14 +09:00
Tom Lane
188cd4f440 Remove faulty support for MergeAppend plan with WHERE CURRENT OF.
Somebody extended search_plan_tree() to treat MergeAppend exactly
like Append, which is 100% wrong, because unlike Append we can't
assume that only one input node is actively returning tuples.
Hence a cursor using a MergeAppend across a UNION ALL or inheritance
tree could falsely match a WHERE CURRENT OF query at a row that
isn't actually the cursor's current output row, but coincidentally
has the same TID (in a different table) as the current output row.

Delete the faulty code; this means that such a case will now return
an error like 'cursor "foo" is not a simply updatable scan of table
"bar"', instead of silently misbehaving.  Users should not find that
surprising though, as the same cursor query could have failed that way
already depending on the chosen plan.  (It would fail like that if the
sort were done with an explicit Sort node instead of MergeAppend.)

Expand the clearly-inadequate commentary to be more explicit about
what this code is doing, in hopes of forestalling future mistakes.

It's been like this for awhile, so back-patch to all supported
branches.

Discussion: https://postgr.es/m/482865.1611075182@sss.pgh.pa.us
2021-01-19 13:25:40 -05:00
Bruce Momjian
6c183aff18 doc: adjust alignment of doc file list for "pg_waldump.sgml"
Backpatch-through: 10
2021-01-18 18:48:25 -05:00
Tom Lane
f0f53195b5 Avoid crash with WHERE CURRENT OF and a custom scan plan.
execCurrent.c's search_plan_tree() assumed that ForeignScanStates
and CustomScanStates necessarily have a valid ss_currentRelation.
This is demonstrably untrue for postgres_fdw's remote join and
remote aggregation plans, and non-leaf custom scans might not have
an identifiable scan relation either.  Avoid crashing by ignoring
such nodes when the field is null.

This solution will lead to errors like 'cursor "foo" is not a
simply updatable scan of table "bar"' in cases where maybe we
could have allowed WHERE CURRENT OF to work.  That's not an issue
for postgres_fdw's usages, since joins or aggregations would render
WHERE CURRENT OF invalid anyway.  But an otherwise-transparent
upper level custom scan node might find this annoying.  When and if
someone cares to expend work on such a scenario, we could invent a
custom-scan-provider callback to determine what's safe.

Report and patch by David Geier, commentary by me.  It's been like
this for awhile, so back-patch to all supported branches.

Discussion: https://postgr.es/m/0253344d-9bdd-11c4-7f0d-d88c02cd7991@swarm64.com
2021-01-18 18:32:40 -05:00
Noah Misch
b8daf894f0 Fix pg_dump for GRANT OPTION among initial privileges.
The context is an object that no longer bears some aclitem that it bore
initially.  (A user issued REVOKE or GRANT statements upon the object.)
pg_dump is forming SQL to reproduce the object ACL.  Since initdb
creates no ACL bearing GRANT OPTION, reaching this bug requires an
extension where the creation script establishes such an ACL.  No PGXN
extension does that.  If an installation did reach the bug, pg_dump
would have omitted a semicolon, causing a REVOKE and the next SQL
statement to fail.  Separately, since the affected code exists to
eliminate an entire aclitem, it wants plain REVOKE, not REVOKE GRANT
OPTION FOR.  Back-patch to 9.6, where commit
23f34fa4ba first appeared.

Discussion: https://postgr.es/m/20210109102423.GA160022@rfd.leadboat.com
2021-01-16 12:21:38 -08:00
Noah Misch
6eb3fc7fcd Prevent excess SimpleLruTruncate() deletion.
Every core SLRU wraps around.  With the exception of pg_notify, the wrap
point can fall in the middle of a page.  Account for this in the
PagePrecedes callback specification and in SimpleLruTruncate()'s use of
said callback.  Update each callback implementation to fit the new
specification.  This changes SerialPagePrecedesLogically() from the
style of asyncQueuePagePrecedes() to the style of CLOGPagePrecedes().
(Whereas pg_clog and pg_serial share a key space, pg_serial is nothing
like pg_notify.)  The bug fixed here has the same symptoms and user
followup steps as 592a589a04.  Back-patch
to 9.5 (all supported versions).

Reviewed by Andrey Borodin and (in earlier versions) by Tom Lane.

Discussion: https://postgr.es/m/20190202083822.GC32531@gust.leadboat.com
2021-01-16 12:21:38 -08:00
Tomas Vondra
d26d4c717d Disallow CREATE STATISTICS on system catalogs
Add a check that CREATE STATISTICS does not add extended statistics on
system catalogs, similarly to indexes etc.  It can be overriden using
the allow_system_table_mods GUC.

This bug exists since 7b504eb282, adding the extended statistics, so
backpatch all the way back to PostgreSQL 10.

Author: Tomas Vondra
Reported-by: Dean Rasheed
Backpatch-through: 10
Discussion: https://postgr.es/m/CAEZATCXAPrrOKwEsyZKQ4uzzJQWBCt6QAvOcgqRGdWwT1zb%2BrQ%40mail.gmail.com
2021-01-15 23:32:54 +01:00
Tom Lane
f44ae4db5f Improve our heuristic for selecting PG_SYSROOT on macOS.
In cases where Xcode is newer than the underlying macOS version,
asking xcodebuild for the SDK path will produce a pointer to the
SDK shipped with Xcode, which may end up building code that does
not work on the underlying macOS version.  It appears that in
such cases, xcodebuild's answer also fails to match the default
behavior of Apple's compiler: assuming one has installed Xcode's
"command line tools", there will be an SDK for the OS's own version
in /Library/Developer/CommandLineTools, and the compiler will
default to using that.  This is all pretty poorly documented,
but experimentation suggests that "xcrun --show-sdk-path" gives
the sysroot path that the compiler is actually using, at least
in some cases.  Hence, try that first, but revert to xcodebuild
if xcrun fails (in very old Xcode, it is missing or lacks the
--show-sdk-path switch).

Also, "xcrun --show-sdk-path" may give a path that is valid but lacks
any OS version identifier.  We don't really want that, since most
of the motivation for wiring -isysroot into the build flags at all
is to ensure that all parts of a PG installation are built against
the same SDK, even when considering extensions built later and/or on
a different machine.  Insist on finding "N.N" in the directory name
before accepting the result.  (Adding "--sdk macosx" to the xcrun
call seems to produce the same answer as xcodebuild, but usually
more quickly because it's cached, so we also try that as a fallback.)

The core reason why we don't want to use Xcode's default SDK in cases
like this is that Apple's technology for introducing new syscalls
does not play nice with Autoconf: for example, configure will think
that preadv/pwritev exist when using a Big Sur SDK, even when building
on an older macOS version where they don't exist.  It'd be nice to
have a better solution to that problem, but this patch doesn't attempt
to fix that.

Per report from Sergey Shinderuk.  Back-patch to all supported versions.

Discussion: https://postgr.es/m/ed3b8e5d-0da8-6ebd-fd1c-e0ac80a4b204@postgrespro.ru
2021-01-15 11:29:05 -05:00
Fujii Masao
60369db86f Fix calculation of how much shared memory is required to store a TOC.
Commit ac883ac453 refactored shm_toc_estimate() but changed its calculation
of shared memory size for TOC incorrectly. Previously this could cause too
large memory to be allocated.

Back-patch to v11 where the bug was introduced.

Author: Takayuki Tsunakawa
Discussion: https://postgr.es/m/TYAPR01MB2990BFB73170E2C4921E2C4DFEA80@TYAPR01MB2990.jpnprd01.prod.outlook.com
2021-01-15 12:45:25 +09:00
Tom Lane
79d3ac72f6 pg_dump: label PUBLICATION TABLE ArchiveEntries with an owner.
This is the same fix as commit 9eabfe300 applied to INDEX ATTACH
entries, but for table-to-publication attachments.  As in that
case, even though the backend doesn't record "ownership" of the
attachment, we still ought to label it in the dump archive with
the role name that should run the ALTER PUBLICATION command.
The existing behavior causes the ALTER to be done by the original
role that started the restore; that will usually work fine, but
there may be corner cases where it fails.

The bulk of the patch is concerned with changing struct
PublicationRelInfo to include a pointer to the associated
PublicationInfo object, so that we can get the owner's name
out of that when the time comes.  While at it, I rewrote
getPublicationTables() to do just one query of pg_publication_rel,
not one per table.

Back-patch to v10 where this code was introduced.

Discussion: https://postgr.es/m/1165710.1610473242@sss.pgh.pa.us
2021-01-14 16:19:38 -05:00
Alvaro Herrera
5b01a6f13f
Prevent drop of tablespaces used by partitioned relations
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>
2021-01-14 15:32:14 -03:00
Fujii Masao
8523a0971b Stabilize timeline switch regression test.
Commit fef5b47f6b added the regression test to check whether a standby is
able to follow a primary on a newer timeline when WAL archiving is enabled.
But the buildfarm member florican reported that this test failed because
the requested WAL segment was removed and replication failed. This is a
timing issue. Since neither replication slot is used nor wal_keep_size is set
in the test, checkpoint could remove the WAL segment that's still necessary
for replication.

This commit stabilizes the test by setting wal_keep_size.

Back-patch to v13 where the regression test that this commit stabilizes
was added.

Author: Fujii Masao
Discussion: https://postgr.es/m/X//PsenxcC50jDzX@paquier.xyz
2021-01-14 23:56:45 +09:00
Fujii Masao
94f52929a0 Ensure that a standby is able to follow a primary on a newer timeline.
Commit 709d003fbd refactored WAL-reading code, but accidentally caused
WalSndSegmentOpen() to fail to follow a timeline switch while reading from
a historic timeline. This issue caused a standby to fail to follow a primary
on a newer timeline when WAL archiving is enabled.

If there is a timeline switch within the segment, WalSndSegmentOpen() should
read from the WAL segment belonging to the new timeline. But previously
since it failed to follow a timeline switch, it tried to read the WAL segment
with old timeline. When WAL archiving is enabled, that WAL segment with
old timeline doesn't exist because it's renamed to .partial. This leads
a primary to have tried to read non-existent WAL segment, and which caused
replication to faill with the error "ERROR:  requested WAL segment ... has
 already been removed".

This commit fixes WalSndSegmentOpen() so that it's able to follow a timeline
switch, to ensure that a standby is able to follow a primary on a newer
timeline even when WAL archiving is enabled.

This commit also adds the regression test to check whether a standby is
able to follow a primary on a newer timeline when WAL archiving is enabled.

Back-patch to v13 where the bug was introduced.

Reported-by: Kyotaro Horiguchi
Author: Kyotaro Horiguchi, tweaked by Fujii Masao
Reviewed-by:  Alvaro Herrera, Fujii Masao
Discussion: https://postgr.es/m/20201209.174314.282492377848029776.horikyota.ntt@gmail.com
2021-01-14 12:28:47 +09:00
Alvaro Herrera
c285a244f6
Call out vacuum considerations in create index docs
Backpatch to pg12, which is as far as it goes without conflicts.

Author: James Coleman <jtc331@gmail.com>
Reviewed-by: "David G. Johnston" <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAAaqYe9oEfbz7AxXq7OX+FFVi5w5p1e_Of8ON8ZnKO9QqBfmjg@mail.gmail.com
2021-01-13 17:55:41 -03:00