Commit Graph

7848 Commits

Author SHA1 Message Date
Andres Freund
eba331ae2a pgstat: Mention pgstat_replslot.c in pgstat.c.
Oversight, by me, in commit 5891c7a8ed.

Author: "Drouvot, Bertrand" <bdrouvot@amazon.com>
Discussion: https://postgr.es/m/bd58e027-6598-57a2-679b-d576d17bfaa9@amazon.com
2022-06-22 16:50:14 -07:00
Tomas Vondra
e3fcca0d0d Revert changes in HOT handling of BRIN indexes
This reverts commits 5753d4ee32 and fe60b67250 that modified HOT to
ignore BRIN indexes. The commit message for 5753d4ee32 claims that:

    When determining whether an index update may be skipped by using
    HOT, we can ignore attributes indexed only by BRIN indexes. There
    are no index pointers to individual tuples in BRIN, and the page
    range summary will be updated anyway as it relies on visibility
    info.

This is partially incorrect - it's true BRIN indexes don't point to
individual tuples, so HOT chains are not an issue, but the visibitlity
info is not sufficient to keep the index up to date. This can easily
result in corrupted indexes, as demonstrated in the hackers thread.

This does not mean relaxing the HOT restrictions for BRIN is a lost
cause, but it needs to handle the two aspects (allowing HOT chains and
updating the page range summaries) as separate. But that requires a
major changes, and it's too late for that in the current dev cycle.

Reported-by: Tomas Vondra
Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com
2022-06-16 15:02:49 +02:00
Tom Lane
7ab5b4eb48 Be more careful about GucSource for internally-driven GUC settings.
The original advice for hard-wired SetConfigOption calls was to use
PGC_S_OVERRIDE, particularly for PGC_INTERNAL GUCs.  However,
that's really overkill for PGC_INTERNAL GUCs, since there is no
possibility that we need to override a user-provided setting.
Instead use PGC_S_DYNAMIC_DEFAULT in most places, so that the
value will appear with source = 'default' in pg_settings and thereby
not be shown by psql's new \dconfig command.  The one exception is
that when changing in_hot_standby in a hot-standby session, we still
use PGC_S_OVERRIDE, because people felt that seeing that in \dconfig
would be a good thing.

Similarly use PGC_S_DYNAMIC_DEFAULT for the auto-tune value of
wal_buffers (if possible, that is if wal_buffers wasn't explicitly
set to -1), and for the typical 2MB value of max_stack_depth.

In combination these changes remove four not-very-interesting
entries from the typical output of \dconfig, all of which people
fingered as "why is that showing up?" in the discussion thread.

Discussion: https://postgr.es/m/3118455.1649267333@sss.pgh.pa.us
2022-06-08 13:26:18 -04:00
Tom Lane
16c80e7d0c Ensure ParseTzFile() closes the input file after failing.
We hadn't noticed this because (a) few people feed invalid
timezone abbreviation files to the server, and (b) in typical
scenarios guc.c would throw ereport(ERROR) and then transaction
abort handling would silently clean up the leaked file reference.
However, it was possible to observe file leakage warnings if one
breaks an already-active abbreviation file, because guc.c does
not throw ERROR when loading supposedly-validated settings during
session start or SIGHUP processing.

Report and fix by Kyotaro Horiguchi (cosmetic adjustments by me)

Discussion: https://postgr.es/m/20220530.173740.748502979257582392.horikyota.ntt@gmail.com
2022-05-31 14:47:44 -04:00
Andres Freund
0107855b14 Align stats_fetch_consistency definition with guc.c default.
Somewhat embarrassing oversight in 98f897339b. Does not have a functional
impact, but is unnecessarily confusing.

Reported-By: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/Yo2351qVYqd/bJws@paquier.xyz
2022-05-28 13:11:59 -07:00
Michael Paquier
f1431f3bff Handle NULL for short descriptions of custom GUC variables
If a short description is specified as NULL in one of the various
DefineCustomXXXVariable() functions available to external modules to
define a custom parameter, SHOW ALL would crash.  This change teaches
SHOW ALL to properly handle NULL short descriptions, as well as any code
paths that manipulate it, to gain in flexibility.  Note that
help_config.c was already able to do that, when describing a set of GUCs
for postgres --describe-config.

Author: Steve Chavez
Reviewed by: Nathan Bossart, Andres Freund, Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com
Backpatch-through: 10
2022-05-28 12:12:40 +09:00
Tom Lane
6217053f4e Avoid ERRCODE_INTERNAL_ERROR in oracle_compat.c functions.
repeat() checked for integer overflow during its calculation of the
required output space, but it just passed the resulting integer to
palloc().  This meant that result sizes between 1GB and 2GB led to
ERRCODE_INTERNAL_ERROR, "invalid memory alloc request size" rather
than ERRCODE_PROGRAM_LIMIT_EXCEEDED, "requested length too large".
That seems like a bit of a wart, so add an explicit AllocSizeIsValid
check to make these error cases uniform.

Do likewise in the sibling functions lpad() etc.  While we're here,
also modernize their overflow checks to use pg_mul_s32_overflow() etc
instead of expensive divisions.

Per complaint from Japin Li.  This is basically cosmetic, so I don't
feel a need to back-patch.

Discussion: https://postgr.es/m/ME3P282MB16676ED32167189CB0462173B6D69@ME3P282MB1667.AUSP282.PROD.OUTLOOK.COM
2022-05-26 12:25:10 -04:00
Andres Freund
98f897339b Fix stats_fetch_consistency default value indicated in postgresql.conf.sample.
Mistake in 5891c7a8ed, likely made when switching the default value from none
to fetch during development.

Reported-By: Nathan Bossart <nathandbossart@gmail.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/20220524220147.GA1298892@nathanxps13
2022-05-24 21:26:39 -07:00
Michael Paquier
c9dfe2e83a Remove duplicated words in comments of pgstat.c and pgstat_internal.h
Author: Atsushi Torikoshi
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/d00ddbf29f9d09b3a471e64977560de1@oss.nttdata.com
2022-05-24 11:00:41 +09:00
John Naylor
6e647ef0e7 Remove debug messages from tuplesort_sort_memtuples()
These were of value only during development.

Reported by Justin Pryzby
Discussion: https://www.postgresql.org/message-id/20220519201254.GU19626%40telsasoft.com
2022-05-23 13:11:43 +07:00
Tom Lane
c7461fc255 Show 'AS "?column?"' explicitly when it's important.
ruleutils.c was coded to suppress the AS label for a SELECT output
expression if the column name is "?column?", which is the parser's
fallback if it can't think of something better.  This is fine, and
avoids ugly clutter, so long as (1) nothing further up in the parse
tree relies on that column name or (2) the same fallback would be
assigned when the rule or view definition is reloaded.  Unfortunately
(2) is far from certain, both because ruleutils.c might print the
expression in a different form from how it was originally written
and because FigureColname's rules might change in future releases.
So we shouldn't rely on that.

Detecting exactly whether there is any outer-level use of a SELECT
column name would be rather expensive.  This patch takes the simpler
approach of just passing down a flag indicating whether there *could*
be any outer use; for example, the output column names of a SubLink
are not referenceable, and we also do not care about the names exposed
by the right-hand side of a setop.  This is sufficient to suppress
unwanted clutter in all but one case in the regression tests.  That
seems like reasonable evidence that it won't be too much in users'
faces, while still fixing the cases we need to fix.

Per bug #17486 from Nicolas Lutic.  This issue is ancient, so
back-patch to all supported branches.

Discussion: https://postgr.es/m/17486-1ad6fd786728b8af@postgresql.org
2022-05-21 14:45:58 -04:00
Tom Lane
3ab9a63cb6 Rename JsonIsPredicate.value_type, fix JSON backend/nodes/ infrastructure.
I started out with the intention to rename value_type to item_type to
avoid a collision with a typedef name that appears on some platforms.

Along the way, I noticed that the adjacent field "format" was not being
correctly handled by the backend/nodes/ infrastructure functions:
copyfuncs.c erroneously treated it as a scalar, while equalfuncs,
outfuncs, and readfuncs omitted handling it at all.  This looks like
it might be cosmetic at the moment because the field is always NULL
after parse analysis; but that's likely a bug in itself, and the code's
certainly not very future-proof.  Let's fix it while we can still do so
without forcing an initdb on beta testers.

Further study found a few other inconsistencies in the backend/nodes/
infrastructure for the recently-added JSON node types, so fix those too.

catversion bumped because of potential change in stored rules.

Discussion: https://postgr.es/m/526703.1652385613@sss.pgh.pa.us
2022-05-13 11:40:08 -04:00
Robert Haas
4f2400cb3f Add a new shmem_request_hook hook.
Currently, preloaded libraries are expected to request additional
shared memory and LWLocks in _PG_init().  However, it is not unusal
for such requests to depend on MaxBackends, which won't be
initialized at that time.  Such requests could also depend on GUCs
that other modules might change.  This introduces a new hook where
modules can safely use MaxBackends and GUCs to request additional
shared memory and LWLocks.

Furthermore, this change restricts requests for shared memory and
LWLocks to this hook.  Previously, libraries could make requests
until the size of the main shared memory segment was calculated.
Unlike before, we no longer silently ignore requests received at
invalid times.  Instead, we FATAL if someone tries to request
additional shared memory or LWLocks outside of the hook.

Nathan Bossart and Julien Rouhaud

Discussion: https://postgr.es/m/20220412210112.GA2065815%40nathanxps13
Discussion: https://postgr.es/m/Yn2jE/lmDhKtkUdr@paquier.xyz
2022-05-13 09:31:06 -04:00
Peter Eisentraut
30ed71e423 Indent C code in flex and bison files
In the style of pgindent, done semi-manually.

Discussion: https://www.postgresql.org/message-id/flat/7d062ecc-7444-23ec-a159-acd8adf9b586%40enterprisedb.com
2022-05-13 07:17:29 +02:00
Tom Lane
23e7b38bfe Pre-beta mechanical code beautification.
Run pgindent, pgperltidy, and reformat-dat-files.
I manually fixed a couple of comments that pgindent uglified.
2022-05-12 15:17:30 -04:00
Robert Haas
ab02d702ef Remove non-functional code for unloading loadable modules.
The code for unloading a library has been commented-out for over 12
years, ever since commit 602a9ef5a7, and we're
no closer to supporting it now than we were back then.

Nathan Bossart, reviewed by Michael Paquier and by me.

Discussion: http://postgr.es/m/Ynsc9bRL1caUSBSE@paquier.xyz
2022-05-11 15:30:30 -04:00
David Rowley
c90c16591c Fix some incorrect preprocessor tests in tuplesort specializations
697492434 added 3 new quicksort specialization functions for common
datatypes.

That commit was not very consistent in how it would determine if we're
compiling for 32-bit or 64-bit machines.  It would sometimes use
USE_FLOAT8_BYVAL and at other times check if SIZEOF_DATUM == 8.  This
could cause theoretical problems due to the way USE_FLOAT8_BYVAL is now
defined based on SIZEOF_VOID_P >= 8.  If pointers for some reason were
ever larger than 8-bytes then we'd end up doing 32-bit comparisons
mistakenly.  Let's just always check SIZEOF_DATUM >= 8.

It also seems that ssup_datum_signed_cmp is just never used on 32-bit
builds, so let's just ifdef that out to make sure we never accidentally
use that comparison function on such machines.  This also allows us to
ifdef out 1 of the 3 new specialization quicksort functions in 32-bit
builds which seems to shrink down the binary by over 4KB on my machine.

In passing, also add the missing DatumGetInt32() / DatumGetInt64() macros
in the comparison functions.

Discussion: https://postgr.es/m/CAApHDvqcQExRhtRa9hJrJB_5egs3SUfOcutP3m+3HO8A+fZTPA@mail.gmail.com
Reviewed-by: John Naylor
2022-05-11 11:38:13 +12:00
Peter Eisentraut
9700b250c5 Formatting and punctuation improvements in sample configuration files 2022-05-10 21:15:56 +02:00
Tom Lane
29904f5f2f Revert "Disallow infinite endpoints in generate_series() for timestamps."
This reverts commit eafdf9de06
and its back-branch counterparts.  Corey Huinker pointed out that
we'd discussed this exact change back in 2016 and rejected it,
on the grounds that there's at least one usage pattern with LIMIT
where an infinite endpoint can usefully be used.  Perhaps that
argument needs to be re-litigated, but there's no time left before
our back-branch releases.  To keep our options open, restore the
status quo ante; if we do end up deciding to change things, waiting
one more quarter won't hurt anything.

Rather than just doing a straight revert, I added a new test case
demonstrating the usage with LIMIT.  That'll at least remind us of
the issue if we forget again.

Discussion: https://postgr.es/m/3603504.1652068977@sss.pgh.pa.us
Discussion: https://postgr.es/m/CADkLM=dzw0Pvdqp5yWKxMd+VmNkAMhG=4ku7GnCZxebWnzmz3Q@mail.gmail.com
2022-05-09 11:40:40 -04:00
Noah Misch
a117cebd63 Make relation-enumerating operations be security-restricted operations.
When a feature enumerates relations and runs functions associated with
all found relations, the feature's user shall not need to trust every
user having permission to create objects.  BRIN-specific functionality
in autovacuum neglected to account for this, as did pg_amcheck and
CLUSTER.  An attacker having permission to create non-temp objects in at
least one schema could execute arbitrary SQL functions under the
identity of the bootstrap superuser.  CREATE INDEX (not a
relation-enumerating operation) and REINDEX protected themselves too
late.  This change extends to the non-enumerating amcheck interface.
Back-patch to v10 (all supported versions).

Sergey Shinderuk, reviewed (in earlier versions) by Alexander Lakhin.
Reported by Alexander Lakhin.

Security: CVE-2022-1552
2022-05-09 08:35:08 -07:00
Robert Haas
701d918a42 Fix misleading comments about background worker registration.
Since 6bc8ef0b7f, the maximum number
of backends can't change as background workers are registered, but
these comments still reflect the way things worked prior to that.

Also, per recent discussion, some modules call SetConfigOption()
from _PG_init(). It's not entirely clear to me whether we want to
regard that as a fully supported operation, but since we know it's
a thing that happens, it at least deserves a mention in the comments,
so add that.

Nathan Bossart, reviewed by Anton A. Melnikov

Discussion: http://postgr.es/m/20220419154658.GA2487941@nathanxps13
2022-05-06 09:24:06 -04:00
Andrew Dunstan
9c3d25e178 Fix JSON_OBJECTAGG uniquefying bug
Commit f4fb45d15c contained a bug in removing items with null values when
unique keys are required, where the leading items that are sorted
contained such values. Fix that and add a test for it.

Discussion: https://postgr.es/m/CAJA4AWQ_XbSmsNbW226UqNyRLJ+wb=iQkQMj77cQyoNkqtf=2Q@mail.gmail.com
2022-04-28 15:28:20 -04:00
Peter Eisentraut
755df30e48 Fix incorrect format placeholders 2022-04-27 09:49:10 +02:00
Alvaro Herrera
0bd56172b2
Always pfree strings returned by GetDatabasePath
Several places didn't do it, and in many cases it didn't matter because
it would be a small allocation in a short-lived context; but other
places may accumulate a few (for example, in CreateDatabaseUsingFileCopy,
one per tablespace).  In most databases this is highly unlikely to be
very serious either, but it seems better to make the code consistent in
case there's future copy-and-paste.

The only case of actual concern seems to be the aforementioned routine,
which is new with commit 9c08aea6a3, so there's no need to backpatch.

As pointed out by Coverity.
2022-04-25 10:32:13 +02:00
David Rowley
99c754129d Fix performance regression in tuplesort specializations
697492434 added 3 new qsort specialization functions aimed to improve the
performance of sorting many of the common pass-by-value data types when
they're the leading or only sort key.

Unfortunately, that has caused a performance regression when sorting
datasets where many of the values being compared were equal.  What was
happening here was that we were falling back to the standard sort
comparison function to handle tiebreaks.  When the two given Datums
compared equally we would incur both the overhead of an indirect function
call to the standard comparer to perform the tiebreak and also the
standard comparer function would go and compare the leading key needlessly
all over again.

Here improve the situation in the 3 new comparison functions.  We now
return 0 directly when the two Datums compare equally and we're performing
a 1-key sort.

Here we don't do anything to help the multi-key sort case where the
leading key uses one of the sort specializations functions.  On testing
this case, even when the leading key's values are all equal, there
appeared to be no performance regression.  Let's leave it up to future
work to optimize that case so that the tiebreak function no longer
re-compares the leading key over again.

Another possible fix for this would have been to add 3 additional sort
specialization functions to handle single-key sorts for these
pass-by-value types.  The reason we didn't do that here is that we may
deem some other sort specialization to be more useful than single-key
sorts.  It may be impractical to have sort specialization functions for
every single combination of what may be useful and it was already decided
that further analysis into which ones are the most useful would be delayed
until the v16 cycle.  Let's not let this regression force our hand into
trying to make that decision for v15.

Author: David Rowley
Reviewed-by: John Naylor
Discussion: https://postgr.es/m/CA+hUKGJRbzaAOUtBUcjF5hLtaSHnJUqXmtiaLEoi53zeWSizeA@mail.gmail.com
2022-04-22 16:02:15 +12:00
Tom Lane
2cb1272445 Rethink method for assigning OIDs to the template0 and postgres DBs.
Commit aa0105141 assigned fixed OIDs to template0 and postgres
in a very ad-hoc way.  Notably, instead of teaching Catalog.pm
about these OIDs, the unused_oids script was just hacked to
not show them as unused.  That's problematic since, for example,
duplicate_oids wouldn't report any future conflict.  Hence,
invent a macro DECLARE_OID_DEFINING_MACRO() that can be used to
define an OID that is known to Catalog.pm and will participate
in duplicate-detection as well as renumbering by renumber_oids.pl.
(We don't anticipate renumbering these particular OIDs, but we
might as well build out all the Catalog.pm infrastructure while
we're here.)

Another issue is that aa0105141 neglected to touch IsPinnedObject,
with the result that it now claimed template0 and postgres are
pinned.  The right thing to do there seems to be to teach it that
no database is pinned, since in fact DROP DATABASE doesn't check
for pinned-ness (and at least for these cases, that is an
intentional choice).  It's not clear whether this wrong answer
had any visible effect, but perhaps it could have resulted in
erroneous management of dependency entries.

In passing, rename the TemplateDbOid macro to Template1DbOid
to reduce confusion (likely we should have done that way back
when we invented template0, but we didn't), and rename the
OID macros for template0 and postgres to have a similar style.

There are no changes to postgres.bki here, so no need for a
catversion bump.

Discussion: https://postgr.es/m/2935358.1650479692@sss.pgh.pa.us
2022-04-21 16:23:15 -04:00
Peter Geoghegan
8ab0ebb9a8 Fix CLUSTER tuplesorts on abbreviated expressions.
CLUSTER sort won't use the datum1 SortTuple field when clustering
against an index whose leading key is an expression.  This makes it
unsafe to use the abbreviated keys optimization, which was missed by the
logic that sets up SortSupport state.  Affected tuplesorts output tuples
in a completely bogus order as a result (the wrong SortSupport based
comparator was used for the leading attribute).

This issue is similar to the bug fixed on the master branch by recent
commit cc58eecc5d.  But it's a far older issue, that dates back to the
introduction of the abbreviated keys optimization by commit 4ea51cdfe8.

Backpatch to all supported versions.

Author: Peter Geoghegan <pg@bowt.ie>
Author: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA+hUKG+bA+bmwD36_oDxAoLrCwZjVtST2fqe=b4=qZcmU7u89A@mail.gmail.com
Backpatch: 10-
2022-04-20 17:17:43 -07:00
Tom Lane
eafdf9de06 Disallow infinite endpoints in generate_series() for timestamps.
Such cases will lead to infinite loops, so they're of no practical
value.  The numeric variant of generate_series() already threw error
for this, so borrow its message wording.

Per report from Richard Wesley.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/91B44E7B-68D5-448F-95C8-B4B3B0F5DEAF@duckdblabs.com
2022-04-20 18:08:23 -04:00
Alvaro Herrera
e70813fbc4
set_deparse_plan: Reuse variable to appease Coverity
Coverity complains that dpns->outer_plan is deferenced (to obtain
->targetlist) when possibly NULL.  We can avoid this by using
dpns->outer_tlist instead, which was already obtained a few lines up.

The fact that we end up with
  dpns->inner_tlist = dpns->outer_tlist
is a bit suspicious-looking and maybe worthy of more investigation, but
I'll leave that for another day.

Reviewed-by: Michaël Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/202204191345.qerjy3kxi3eb@alvherre.pgsql
2022-04-20 11:44:08 +02:00
Peter Eisentraut
f2a2bf66c8 Fix extract epoch from interval calculation
The new numeric code for extract epoch from interval accidentally
truncated the DAYS_PER_YEAR value to an integer, leading to results
that mismatched the floating-point interval_part calculations.

The commit a2da77cdb4 that introduced
this actually contains the regression test change that this reverts.
I suppose this was missed at the time.

Reported-by: Joseph Koshakow <koshy44@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/CAAvxfHd5n%3D13NYA2q_tUq%3D3%3DSuWU-CufmTf-Ozj%3DfrEgt7pXwQ%40mail.gmail.com
2022-04-19 21:04:52 +02:00
Andres Freund
4a736a161c pgstat: Use correct lock level in pgstat_drop_all_entries().
Previously we didn't, which lead to an assertion failure when resetting
partially loaded statistics. This was encountered on the buildfarm, for
as-of-yet unknown reasons.

Ttighten up a validity check when reading the stats file, verifying 'E'
signals the end of the file (rather than just stopping reading). That's then
used in a test appending to the stats file that crashed before the fix in
pgstat_drop_all_entries().

Reported by buildfarm animals mylodon and kestrel, via Tom Lane.

Discussion: https://postgr.es/m/1656446.1650043715@sss.pgh.pa.us
2022-04-16 14:44:58 -07:00
Tom Lane
9f4f0a0dad Fix incorrect logic in HaveRegisteredOrActiveSnapshot().
This function gave the wrong answer when there's more than one
RegisteredSnapshots entry, whether or not any of them is the
CatalogSnapshot.  This leads to assertion failure in some scenarios
involving fetching toasted data using a cursor.  (As per discussion,
I'm dubious that this is the right contract to be enforcing at all;
but it surely doesn't help to be enforcing it incorrectly.)

Fetching toasted data using a cursor is evidently under-tested,
so add a test case too.

Per report from Erik Rijkers.  This is new code, so no need for
back-patch.

Discussion: https://postgr.es/m/dc9dd229-ed30-6c62-4c41-d733ffff776b@xs4all.nl
2022-04-16 16:04:50 -04:00
Andrew Dunstan
f7a605f636 Small cleanups in SQL/JSON code
These are to keep Coverity happy. In one case remove a redundant NULL
check, and in another explicitly ignore a function result that is already
known.
2022-04-15 07:49:20 -04:00
Andres Freund
5cd1c40b3c pgstat: set timestamps of fixed-numbered stats after a crash.
When not loading stats at startup (i.e. pgstat_discard_stats() getting
called), reset timestamps of fixed numbered stats would be left at
0. Oversight in 5891c7a8ed.

Instead use pgstat_reset_after_failure() and add tests verifying that
fixed-numbered reset timestamps are set appropriately.

Reported-By: "David G. Johnston" <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAKFQuwamFuaQHKdhcMt4Gbw5+Hca2UE741B8gOOXoA=TtAd2Yw@mail.gmail.com
2022-04-14 17:40:25 -07:00
Alvaro Herrera
24d2b2680a
Remove extraneous blank lines before block-closing braces
These are useless and distracting.  We wouldn't have written the code
with them to begin with, so there's no reason to keep them.

Author: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20220411020336.GB26620@telsasoft.com
Discussion: https://postgr.es/m/attachment/133167/0016-Extraneous-blank-lines.patch
2022-04-13 19:16:02 +02:00
Andrew Dunstan
112fdb3528 Fix finalization for json_objectagg and friends
Commit f4fb45d15c misguidedly tried to free some state during aggregate
finalization for json_objectagg. This resulted in attempts to access
freed memory, especially when the function is used as a window function.
Commit 4eb9798879 attempted to ameliorate that, but in fact it should
just be ripped out, which is done here. Also add some regression tests
for json_objectagg in various flavors as a window function.

Original report from Jaime Casanova, diagnosis by Andres Freund.

Discussion: https://postgr.es/m/YkfeMNYRCGhySKyg@ahch-to
2022-04-13 10:37:43 -04:00
Peter Eisentraut
a038679cd8 Fix incorrect format placeholders 2022-04-13 14:04:51 +02:00
Robert Haas
7fc0e7de9f Revert the addition of GetMaxBackends() and related stuff.
This reverts commits 0147fc7, 4567596, aa64f23, and 5ecd018.
There is no longer agreement that introducing this function
was the right way to address the problem. The consensus now
seems to favor trying to make a correct value for MaxBackends
available to mdules executing their _PG_init() functions.

Nathan Bossart

Discussion: http://postgr.es/m/20220323045229.i23skfscdbvrsuxa@jrouhaud
2022-04-12 14:45:23 -04:00
Tom Lane
3c702b3ed1 Explicitly ignore guaranteed-true result from pgstat_lock_entry().
With nowait passed as false, pgstat_lock_entry() must return true
so there's no need to check its result.  Coverity seems unconvinced
of this, so whack it upside the head with a (void) cast.
2022-04-11 13:22:37 -04:00
Tom Lane
93fcf2d209 fgetc() returns int, not char.
This has no practical effect, since this code doesn't actually need to
distinguish EOF (-1) from \0377; but it silences a Coverity complaint.
2022-04-11 13:15:46 -04:00
David Rowley
b0e5f02ddc Fix various typos and spelling mistakes in code comments
Author: Justin Pryzby
Discussion: https://postgr.es/m/20220411020336.GB26620@telsasoft.com
2022-04-11 20:49:41 +12:00
Peter Eisentraut
38abc39c81 Add missing serial commas 2022-04-09 16:15:01 +02:00
Peter Eisentraut
708007dced Remove error message hints mentioning configure options
These are usually not useful since users will use packaged
distributions and won't be interested in rebuilding their installation
from source.  Also, we have only used these kinds of hints for some
features and in some places, not consistently throughout.

Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/2552aed7-d0e9-280a-54aa-2dc7073f371d%40enterprisedb.com
2022-04-08 07:41:55 +02:00
David Rowley
9d9c02ccd1 Teach planner and executor about monotonic window funcs
Window functions such as row_number() always return a value higher than
the previously returned value for tuples in any given window partition.

Traditionally queries such as;

SELECT * FROM (
   SELECT *, row_number() over (order by c) rn
   FROM t
) t WHERE rn <= 10;

were executed fairly inefficiently.  Neither the query planner nor the
executor knew that once rn made it to 11 that nothing further would match
the outer query's WHERE clause.  It would blindly continue until all
tuples were exhausted from the subquery.

Here we implement means to make the above execute more efficiently.

This is done by way of adding a pg_proc.prosupport function to various of
the built-in window functions and adding supporting code to allow the
support function to inform the planner if the window function is
monotonically increasing, monotonically decreasing, both or neither.  The
planner is then able to make use of that information and possibly allow
the executor to short-circuit execution by way of adding a "run condition"
to the WindowAgg to allow it to determine if some of its execution work
can be skipped.

This "run condition" is not like a normal filter.  These run conditions
are only built using quals comparing values to monotonic window functions.
For monotonic increasing functions, quals making use of the btree
operators for <, <= and = can be used (assuming the window function column
is on the left). You can see here that once such a condition becomes false
that a monotonic increasing function could never make it subsequently true
again.  For monotonically decreasing functions the >, >= and = btree
operators for the given type can be used for run conditions.

The best-case situation for this is when there is a single WindowAgg node
without a PARTITION BY clause.  Here when the run condition becomes false
the WindowAgg node can simply return NULL.  No more tuples will ever match
the run condition.  It's a little more complex when there is a PARTITION
BY clause.  In this case, we cannot return NULL as we must still process
other partitions.  To speed this case up we pull tuples from the outer
plan to check if they're from the same partition and simply discard them
if they are.  When we find a tuple belonging to another partition we start
processing as normal again until the run condition becomes false or we run
out of tuples to process.

When there are multiple WindowAgg nodes to evaluate then this complicates
the situation.  For intermediate WindowAggs we must ensure we always
return all tuples to the calling node.  Any filtering done could lead to
incorrect results in WindowAgg nodes above.  For all intermediate nodes,
we can still save some work when the run condition becomes false.  We've
no need to evaluate the WindowFuncs anymore.  Other WindowAgg nodes cannot
reference the value of these and these tuples will not appear in the final
result anyway.  The savings here are small in comparison to what can be
saved in the top-level WingowAgg, but still worthwhile.

Intermediate WindowAgg nodes never filter out tuples, but here we change
WindowAgg so that the top-level WindowAgg filters out tuples that don't
match the intermediate WindowAgg node's run condition.  Such filters
appear in the "Filter" clause in EXPLAIN for the top-level WindowAgg node.

Here we add prosupport functions to allow the above to work for;
row_number(), rank(), dense_rank(), count(*) and count(expr).  It appears
technically possible to do the same for min() and max(), however, it seems
unlikely to be useful enough, so that's not done here.

Bump catversion

Author: David Rowley
Reviewed-by: Andy Fan, Zhihong Yu
Discussion: https://postgr.es/m/CAApHDvqvp3At8++yF8ij06sdcoo1S_b2YoaT9D4Nf+MObzsrLQ@mail.gmail.com
2022-04-08 10:34:36 +12:00
Alvaro Herrera
a90641eac2
Revert "Rewrite some RI code to avoid using SPI"
This reverts commit 99392cdd78.
We'd rather rewrite ri_triggers.c as a whole rather than piecemeal.

Discussion: https://postgr.es/m/E1ncXX2-000mFt-Pe@gemulon.postgresql.org
2022-04-07 23:42:13 +02:00
Alvaro Herrera
99392cdd78
Rewrite some RI code to avoid using SPI
Modify the subroutines called by RI trigger functions that want to check
if a given referenced value exists in the referenced relation to simply
scan the foreign key constraint's unique index, instead of using SPI to
execute
  SELECT 1 FROM referenced_relation WHERE ref_key = $1
This saves a lot of work, especially when inserting into or updating a
referencing relation.

This rewrite allows to fix a PK row visibility bug caused by a partition
descriptor hack which requires ActiveSnapshot to be set to come up with
the correct set of partitions for the RI query running under REPEATABLE
READ isolation.  We now set that snapshot indepedently of the snapshot
to be used by the PK index scan, so the two no longer interfere.  The
buggy output in src/test/isolation/expected/fk-snapshot.out of the
relevant test case added by commit 00cb86e75d has been corrected.
(The bug still exists in branch 14, however, but this fix is too
invasive to backpatch.)

Author: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Li Japin <japinli@hotmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CA+HiwqGkfJfYdeq5vHPh6eqPKjSbfpDDY+j-kXYFePQedtSLeg@mail.gmail.com
2022-04-07 21:10:03 +02:00
Tomas Vondra
2c7ea57e56 Revert "Logical decoding of sequences"
This reverts a sequence of commits, implementing features related to
logical decoding and replication of sequences:

 - 0da92dc530
 - 80901b3291
 - b779d7d8fd
 - d5ed9da41d
 - a180c2b34d
 - 75b1521dae
 - 2d2232933b
 - 002c9dd97a
 - 05843b1aa4

The implementation has issues, mostly due to combining transactional and
non-transactional behavior of sequences. It's not clear how this could
be fixed, but it'll require reworking significant part of the patch.

Discussion: https://postgr.es/m/95345a19-d508-63d1-860a-f5c2f41e8d40@enterprisedb.com
2022-04-07 20:06:36 +02:00
Thomas Munro
5dc0418fab Prefetch data referenced by the WAL, take II.
Introduce a new GUC recovery_prefetch.  When enabled, look ahead in the
WAL and try to initiate asynchronous reading of referenced data blocks
that are not yet cached in our buffer pool.  For now, this is done with
posix_fadvise(), which has several caveats.  Since not all OSes have
that system call, "try" is provided so that it can be enabled where
available.  Better mechanisms for asynchronous I/O are possible in later
work.

Set to "try" for now for test coverage.  Default setting to be finalized
before release.

The GUC wal_decode_buffer_size limits the distance we can look ahead in
bytes of decoded data.

The existing GUC maintenance_io_concurrency is used to limit the number
of concurrent I/Os allowed, based on pessimistic heuristics used to
infer that I/Os have begun and completed.  We'll also not look more than
maintenance_io_concurrency * 4 block references ahead.

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com> (earlier version)
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> (earlier version)
Tested-by: Tomas Vondra <tomas.vondra@2ndquadrant.com> (earlier version)
Tested-by: Jakub Wartak <Jakub.Wartak@tomtom.com> (earlier version)
Tested-by: Dmitry Dolgov <9erthalion6@gmail.com> (earlier version)
Tested-by: Sait Talha Nisanci <Sait.Nisanci@microsoft.com> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKGJ4VJN8ttxScUFM8dOKX0BrBiboo5uz1cq%3DAovOddfHpA%40mail.gmail.com
2022-04-07 19:42:14 +12:00
Andres Freund
ad401664b8 pgstat: add pg_stat_have_stats() test helper.
Will be used by tests committed subsequently.

Bumps catversion (this time for real, the one in 0f96965c65 got lost when
rebasing over 5c279a6d35).

Author: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_aNxL1WegCa45r=VAViCLnpOU7uNC7bTtGw+=QAPyYivw@mail.gmail.com
2022-04-07 00:21:54 -07:00
Andres Freund
0f96965c65 pgstat: add pg_stat_force_next_flush(), use it to simplify tests.
In the stats collector days it was hard to write tests for the stats system,
because fundamentally delivery of stats messages over UDP was not
synchronous (nor guaranteed). Now we easily can force pending stats updates to
be flushed synchronously.

This moves stats.sql into a parallel group, there isn't a reason for it to run
in isolation anymore. And it may shake out some bugs.

Bumps catversion.

Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220303021600.hs34ghqcw6zcokdh@alap3.anarazel.de
2022-04-06 23:35:56 -07:00