Commits 146604ec43 and a898b409f6 added overflow checks to
interval_mul(), but not to interval_div(), which contains almost
identical code, and so is susceptible to the same kinds of
overflows. In addition, those checks did not catch all possible
overflow conditions.
Add additional checks to the "cascade down" code in interval_mul(),
and copy all the overflow checks over to the corresponding code in
interval_div(), so that they both generate "interval out of range"
errors, rather than returning bogus results.
Given that these errors are relatively easy to hit, back-patch to all
supported branches.
Per bug #18200 from Alexander Lakhin, and subsequent investigation.
Discussion: https://postgr.es/m/18200-5ea288c7b2d504b1%40postgresql.org
examine_simple_variable() left this as an unimplemented case years
ago, with the result that plans for queries involving un-flattened
CTEs might be much stupider than necessary. It's not hard to extend
the existing logic for RTE_SUBQUERY cases to also be able to drill
down into CTEs, so let's do that.
There was some discussion of whether this patch breaks the idea
of a MATERIALIZED CTE being an optimization fence. We concluded
it's okay, because we already allow the outer planner level to
see the estimated width and rowcount of the CTE result, and
letting it see column statistics too seems fairly equivalent.
Basically, what we expect of the optimization fence is that the
outer query should not affect the plan chosen for the CTE query.
Once that plan is chosen, it's okay for the outer planner level
to make use of whatever information we have about it.
Jian Guo and Tom Lane, per complaint from Hans Buschmann
Discussion: https://postgr.es/m/4504e67078d648cdac3651b2960da6e7@nidsa.net
A few places in array_in() and plperl would report a misleading value
(always MAXDIM+1) for the number of dimensions in the input, because
we'd error out as soon as that was clearly too large rather than
scanning the entire input. There doesn't seem to be much value in
offering the true number, at least not enough to justify the extra
complication involved in trying to get it. So just remove that
parenthetical remark. We already have other places that do it
like that, anyway.
Per suggestions from Alexander Lakhin and Heikki Linnakangas.
Discussion: https://postgr.es/m/2794005.1683042087@sss.pgh.pa.us
The code previously relied on "long" as type to track block numbers,
which would be 4 bytes in all Windows builds or any 32-bit builds. This
limited the code to be able to handle up to 16TB of data with the
default block size of 8kB, like during a CLUSTER. This code now relies
on a more portable int64, which should be more than enough for at least
the next 20 years to come.
This issue has been reported back in 2017, but nothing was done about it
back then, so here we go now.
Reported-by: Peter Geoghegan
Reviewed-by: Heikki Linnakangas
Discussion: https://postgr.es/m/CAH2-WznCscXnWmnj=STC0aSa7QG+BRedDnZsP=Jo_R9GUZvUrg@mail.gmail.com
Currently, pg_stat_reset_shared() cannot reset the counters in the view
pg_stat_slru even if it is a type of shared stats. This patch adds
support for a new value in pg_stat_reset_shared(), called "slru", able
to do that. Note that pg_stat_reset_shared(NULL) also resets SLRU
counters.
There may be a point in removing pg_stat_reset_slru() that was
introduced in 28cac71bd3 (v13~) as the new option overlaps with this
function, but we would lose the ability to reset individual SLRU
counters. This is left for future reconsideration.
Author: Atsushi Torikoshi
Discussion: https://postgr.es/m/e3c25d72e81378e7b64f3c52e0306fc9@oss.nttdata.com
As of commit eaa5808e8e, MemoryContextResetAndDeleteChildren() is
just a backwards compatibility macro for MemoryContextReset(). Now
that some time has passed, this macro seems more likely to create
confusion.
This commit removes the macro and replaces all remaining uses with
calls to MemoryContextReset(). Any third-party code that use this
macro will need to be adjusted to call MemoryContextReset()
instead. Since the two have behaved the same way since v9.5, such
adjustments won't produce any behavior changes for all
currently-supported versions of PostgreSQL.
Reviewed-by: Amul Sul, Tom Lane, Alvaro Herrera, Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/20231113185950.GA1668018%40nathanxps13
The comments in dsa.c suggested that areas were owned by resource
owners, but it was not in fact tracked explicitly. The DSM attachments
held by the dsa were owned by resource owners, but not the area
itself. That led to confusion if you used one resource owner to
attach or create the area, but then switched to a different resource
owner before allocating or even just accessing the allocations in the
area with dsa_get_address(). The additional DSM segments associated
with the area would get owned by a different resource owner than the
initial segment. To fix, add an explicit 'resowner' field to
dsa_area. It replaces the 'mapping_pinned' flag; resowner == NULL now
indicates that the mapping is pinned.
This is arguably a bug fix, but I'm not backpatching because it
doesn't seem to be a live bug in the back branches. In 'master', it is
a bug because commit b8bff07daa made ResourceOwners more strict so
that you are no longer allowed to remember new resources in a
ResourceOwner after you have started to release it. Merely accessing a
dsa pointer might need to attach a new DSM segment, and before this
commit it was temporarily remembered in the current owner for a very
brief period even if the DSA was pinned. And that could happen in
AtEOXact_PgStat(), which is called after the owner is already released.
Reported-by: Alexander Lakhin
Reviewed-by: Alexander Lakhin, Thomas Munro, Andres Freund
Discussion: https://www.postgresql.org/message-id/11b70743-c5f3-3910-8e5b-dd6c115ff829%40gmail.com
This adds support for infinity to the interval data type, using the
same input/output representation as the other date/time data types
that support infinity. This allows various arithmetic operations on
infinite dates, timestamps and intervals.
The new values are represented by setting all fields of the interval
to INT32/64_MIN for -infinity, and INT32/64_MAX for +infinity. This
ensures that they compare as less/greater than all other interval
values, without the need for any special-case comparison code.
Note that, since those 2 values were formerly accepted as legal finite
intervals, pg_upgrade and dump/restore from an old database will turn
them from finite to infinite intervals. That seems OK, since those
exact values should be extremely rare in practice, and they are
outside the documented range supported by the interval type, which
gives us a certain amount of leeway.
Bump catalog version.
Joseph Koshakow, Jian He, and Ashutosh Bapat, reviewed by me.
Discussion: https://postgr.es/m/CAAvxfHea4%2BsPybKK7agDYOMo9N-Z3J6ZXf3BOM79pFsFNcRjwA%40mail.gmail.com
To generate a dummy probes.h file when dtrace is not available, we had
two different scripts: A sed version, which is the original version,
and a Perl version, which was generated by s2p. This split was
necessary because Perl was not a mandatory build dependency on Unix,
but sed was not guaranteed to be available on Windows.
(The Meson build system used the sed version even on Windows, which
was probably incorrect and probably would have had to be fixed before
elevating that build system from experimental status.)
As of 721856ff24, Perl is a required build dependency, so this split
is no longer necessary. We can just use the Perl script in all build
environments and remove a whole bunch of infrastructure to keep the
two variants in sync.
The new Gen_dummy_probes.pl is not the version generated by s2p but a
new implementation written by hand by adapting the sed version to Perl
syntax.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/3fd0f1bc-4483-4ba9-8aa0-64765b052039@eisentraut.org
Rewrite array_in() and its subroutines so that we make only one
pass over the input text, rather than two. This requires
potentially re-pallocing the working arrays values[] and nulls[]
larger than our initial guess, but that cost will hopefully be made
up by avoiding duplicate parsing. In any case this coding seems
much clearer and more straightforward than what we had before.
This also fixes array_in() to reject non-rectangular input (that is,
different brace depths in different parts of the input) more reliably
than before, and to give a better error message when it does so.
This is analogous to the plpython and plperl fixes in 0553528e7 and
f47004add. Like those PLs, we now accept input such as '{{},{}}'
as a valid representation of an empty array, which we did not before.
Additionally, reject explicit array subscripts that are outside the
integer range (previously you just got whatever atoi() converted
them to), and make some other minor improvements in error reporting.
Although this is arguably a bug fix, it's also a behavioral change
that might trip somebody up, so no back-patch.
Tom Lane, Heikki Linnakangas, and Jian He. Thanks to Alexander Lakhin
for the initial report and for review/testing.
Discussion: https://postgr.es/m/2794005.1683042087@sss.pgh.pa.us
Currently, pg_stat_reset_shared() can use an argument to specify the
target of statistics to reset, doing nothing for NULL as it is strict.
This patch adds to pg_stat_reset_shared() the possibility to reset all
the stats types already handled in this function rather than do nothing
if the argument value given is NULL or if nothing is specified
(proisstrict is switched to false). Like previously, SLRUs are not
included in what gets reset.
The idea to use NULL or no argument to control if all the shared stats
already covered by this function should be reset has been proposed by
Andres Freund.
Bump catalog version.
Author: Atsushi Torikoshi
Reviewed-by: Kyotaro Horiguchi, Michael Paquier, Bharath Rupireddy,
Matthias van de Meent
Discussion: https://postgr.es/m/4291a55137ddda77cf7cc5f46e846daf@oss.nttdata.com
We don't want existing slots in the old cluster to get invalidated during
the upgrade. During an upgrade, we set this variable to -1 via the command
line in an attempt to prevent such invalidations, but users have ways to
override it. This patch ensures the value is not overridden by the user.
Author: Kyotaro Horiguchi
Reviewed-by: Peter Smith, Alvaro Herrera
Discussion: http://postgr.es/m/20231027.115759.2206827438943188717.horikyota.ntt@gmail.com
When casting an interval to a time, the original code suffered from
64-bit integer overflow for inputs with a sufficiently large negative
"time" field, leading to bogus results.
Fix by rewriting the algorithm in a simpler form, that more obviously
cannot overflow. While at it, improve the test coverage to include
negative interval inputs.
Discussion: https://postgr.es/m/CAEZATCXoUKHkcuq4q63hkiPsKZJd0kZWzgKtU%2BNT0aU4wbf_Pw%40mail.gmail.com
When the hash table is in use, ResoureOwnerSort() moves any elements
from the small fixed-size array to the hash table, and sorts it. When
the hash table is not in use, it sorts the elements in the small
fixed-size array directly. However, ResourceOwnerSort() and
ResourceOwnerReleaseAll() had different idea on when the hash table is
in use: ResourceOwnerSort() checked owner->nhash != 0, and
ResourceOwnerReleaseAll() checked owner->hash != NULL. If the hash
table was allocated but was currently empty, you hit an assertion
failure.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://www.postgresql.org/message-id/be58d565-9e95-d417-4e47-f6bd408dea4b@gmail.com
This buys back some of the performance loss that we otherwise saw from the
previous commit.
Reviewed-by: Aleksander Alekseev, Michael Paquier, Julien Rouhaud
Reviewed-by: Kyotaro Horiguchi, Hayato Kuroda, Álvaro Herrera, Zhihong Yu
Reviewed-by: Peter Eisentraut, Andres Freund
Discussion: https://www.postgresql.org/message-id/d746cead-a1ef-7efe-fb47-933311e876a3%40iki.fi
Instead of having a separate array/hash for each resource kind, use a
single array and hash to hold all kinds of resources. This makes it
possible to introduce new resource "kinds" without having to modify
the ResourceOwnerData struct. In particular, this makes it possible
for extensions to register custom resource kinds.
The old approach was to have a small array of resources of each kind,
and if it fills up, switch to a hash table. The new approach also uses
an array and a hash, but now the array and the hash are used at the
same time. The array is used to hold the recently added resources, and
when it fills up, they are moved to the hash. This keeps the access to
recent entries fast, even when there are a lot of long-held resources.
All the resource-specific ResourceOwnerEnlarge*(),
ResourceOwnerRemember*(), and ResourceOwnerForget*() functions have
been replaced with three generic functions that take resource kind as
argument. For convenience, we still define resource-specific wrapper
macros around the generic functions with the old names, but they are
now defined in the source files that use those resource kinds.
The release callback no longer needs to call ResourceOwnerForget on
the resource being released. ResourceOwnerRelease unregisters the
resource from the owner before calling the callback. That needed some
changes in bufmgr.c and some other files, where releasing the
resources previously always called ResourceOwnerForget.
Each resource kind specifies a release priority, and
ResourceOwnerReleaseAll releases the resources in priority order. To
make that possible, we have to restrict what you can do between
phases. After calling ResourceOwnerRelease(), you are no longer
allowed to remember any more resources in it or to forget any
previously remembered resources by calling ResourceOwnerForget. There
was one case where that was done previously. At subtransaction commit,
AtEOSubXact_Inval() would handle the invalidation messages and call
RelationFlushRelation(), which temporarily increased the reference
count on the relation being flushed. We now switch to the parent
subtransaction's resource owner before calling AtEOSubXact_Inval(), so
that there is a valid ResourceOwner to temporarily hold that relcache
reference.
Other end-of-xact routines make similar calls to AtEOXact_Inval()
between release phases, but I didn't see any regression test failures
from those, so I'm not sure if they could reach a codepath that needs
remembering extra resources.
There were two exceptions to how the resource leak WARNINGs on commit
were printed previously: llvmjit silently released the context without
printing the warning, and a leaked buffer io triggered a PANIC. Now
everything prints a WARNING, including those cases.
Add tests in src/test/modules/test_resowner.
Reviewed-by: Aleksander Alekseev, Michael Paquier, Julien Rouhaud
Reviewed-by: Kyotaro Horiguchi, Hayato Kuroda, Álvaro Herrera, Zhihong Yu
Reviewed-by: Peter Eisentraut, Andres Freund
Discussion: https://www.postgresql.org/message-id/cbfabeb0-cd3c-e951-a572-19b365ed314d%40iki.fi
These are functions where a lot of things happen between the
ResourceOwnerEnlarge and ResourceOwnerRemember calls. It's important
that there are no unrelated ResourceOwnerRemember calls in the code in
between, otherwise the reserved entry might be used up by the
intervening ResourceOwnerRemember and not be available at the intended
ResourceOwnerRemember call anymore. I don't see any bugs here, but the
longer the code path between the calls is, the harder it is to verify.
In bufmgr.c, there is a function similar to ResourceOwnerEnlarge,
ReservePrivateRefCountEntry(), to ensure that the private refcount
array has enough space. The ReservePrivateRefCountEntry() calls were
made at different places than the ResourceOwnerEnlargeBuffers()
calls. Move the ResourceOwnerEnlargeBuffers() and
ReservePrivateRefCountEntry() calls together for consistency.
Reviewed-by: Aleksander Alekseev, Michael Paquier, Julien Rouhaud
Reviewed-by: Kyotaro Horiguchi, Hayato Kuroda, Álvaro Herrera, Zhihong Yu
Reviewed-by: Peter Eisentraut, Andres Freund
Discussion: https://www.postgresql.org/message-id/cbfabeb0-cd3c-e951-a572-19b365ed314d%40iki.fi
I added it by mistake in commit 7103ebb7aa. To clean up, struct
MergeAction needs to be moved to primnodes.h from parsenodes.h. (This
forces us to also move OverridingKind to primnodes.h).
Having to add parsenodes.h to bootstrap.h as fallout is a bit
surprising, since nothing nominally needs it there. However, per
comments in bootscanner.l, it is needed so that YYSTYPE can be declared.
I think this only started with commit dac048f71e, but I didn't
actually verify that.
In passing, stop including parsenodes.h in tcopprot.h. Nothing needs it
there.
Per discussion on a patch by Ashutosh Bapat.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202311071106.6y7b2ascqjlz@alvherre.pgsql
array_set_element() and related functions allow an array to be
enlarged by assigning to subscripts outside the current array bounds.
While these places were careful to check that the new bounds are
allowable, they neglected to consider the risk of integer overflow
in computing the new bounds. In edge cases, we could compute new
bounds that are invalid but get past the subsequent checks,
allowing bad things to happen. Memory stomps that are potentially
exploitable for arbitrary code execution are possible, and so is
disclosure of server memory.
To fix, perform the hazardous computations using overflow-detecting
arithmetic routines, which fortunately exist in all still-supported
branches.
The test cases added for this generate (after patching) errors that
mention the value of MaxArraySize, which is platform-dependent.
Rather than introduce multiple expected-files, use psql's VERBOSITY
parameter to suppress the printing of the message text. v11 psql
lacks that parameter, so omit the tests in that branch.
Our thanks to Pedro Gallegos for reporting this problem.
Security: CVE-2023-5869
A PostgreSQL release tarball contains a number of prebuilt files, in
particular files produced by bison, flex, perl, and well as html and
man documentation. We have done this consistent with established
practice at the time to not require these tools for building from a
tarball. Some of these tools were hard to get, or get the right
version of, from time to time, and shipping the prebuilt output was a
convenience to users.
Now this has at least two problems:
One, we have to make the build system(s) work in two modes: Building
from a git checkout and building from a tarball. This is pretty
complicated, but it works so far for autoconf/make. It does not
currently work for meson; you can currently only build with meson from
a git checkout. Making meson builds work from a tarball seems very
difficult or impossible. One particular problem is that since meson
requires a separate build directory, we cannot make the build update
files like gram.h in the source tree. So if you were to build from a
tarball and update gram.y, you will have a gram.h in the source tree
and one in the build tree, but the way things work is that the
compiler will always use the one in the source tree. So you cannot,
for example, make any gram.y changes when building from a tarball.
This seems impossible to fix in a non-horrible way.
Second, there is increased interest nowadays in precisely tracking the
origin of software. We can reasonably track contributions into the
git tree, and users can reasonably track the path from a tarball to
packages and downloads and installs. But what happens between the git
tree and the tarball is obscure and in some cases non-reproducible.
The solution for both of these issues is to get rid of the step that
adds prebuilt files to the tarball. The tarball now only contains
what is in the git tree (*). Getting the additional build
dependencies is no longer a problem nowadays, and the complications to
keep these dual build modes working are significant. And of course we
want to get the meson build system working universally.
This commit removes the make distprep target altogether. The make
dist target continues to do its job, it just doesn't call distprep
anymore.
(*) - The tarball also contains the INSTALL file that is built at make
dist time, but not by distprep. This is unchanged for now.
The make maintainer-clean target, whose job it is to remove the
prebuilt files in addition to what make distclean does, is now just an
alias to make distprep. (In practice, it is probably obsolete given
that git clean is available.)
The following programs are now hard build requirements in configure
(they were already required by meson.build):
- bison
- flex
- perl
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/e07408d9-e5f2-d9fd-5672-f53354e9305e@eisentraut.org
It was always false in single-user mode, in autovacuum workers, and in
background workers. This had no specifically-identified security
consequences, but non-core code or future work might make it
security-relevant. Back-patch to v11 (all supported versions).
Jelte Fennema-Nio. Reported by Jelte Fennema-Nio.
This function implements the standard XMLTest function, which
converts text into xml text nodes. It uses the libxml2 function
xmlEncodeSpecialChars to escape predefined entities (&"<>), so
that those do not cause any conflict when concatenating the text
node output with existing xml documents.
This also adds a note in features.sgml about not supporting
XML(SEQUENCE). The SQL specification defines a RETURNING clause
to a set of XML functions, where RETURNING CONTENT or RETURNING
SEQUENCE can be defined. Since PostgreSQL doesn't support
XML(SEQUENCE) all of these functions operate with an
implicit RETURNING CONTENT.
Author: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Discussion: https://postgr.es/m/86617a66-ec95-581f-8d54-08059cca8885@uni-muenster.de
As per the preceding commit, GUC APIs generally expose NULL-valued
string variables as empty strings. Extend that policy to
GetConfigOption() and GetConfigOptionResetString(), eliminating
a crash hazard for unwary callers, as well as a fundamental
ambiguity in GetConfigOption()'s API.
No back-patch, since this is an API change and conceivably somebody
somewhere is depending on this corner case.
Xing Guo, Aleksander Alekseev, Tom Lane
Discussion: https://postgr.es/m/CACpMh+AyDx5YUpPaAgzVwC1d8zfOL4JoD-uyFDnNSa1z0EsDQQ@mail.gmail.com
get_explain_guc_options() crashed if a string GUC marked GUC_EXPLAIN
has a NULL boot_val. Nosing around found a couple of other places
that seemed insufficiently cautious about NULL string values, although
those are likely unreachable in practice. Add some commentary
defining the expectations for NULL values of string variables,
in hopes of forestalling future additions of more such bugs.
Xing Guo, Aleksander Alekseev, Tom Lane
Discussion: https://postgr.es/m/CACpMh+AyDx5YUpPaAgzVwC1d8zfOL4JoD-uyFDnNSa1z0EsDQQ@mail.gmail.com
Introduce unicode_version(), icu_unicode_version(), and
unicode_assigned().
The latter requires introducing a new lookup table for the Unicode
General Category, which is generated along with the other Unicode
lookup tables.
Discussion: https://postgr.es/m/CA+TgmoYzYR-yhU6k1XFCADeyj=Oyz2PkVsa3iKv+keM8wp-F_A@mail.gmail.com
Reviewed-by: Peter Eisentraut
Historically, the statistics of the checkpointer have been always part
of pg_stat_bgwriter. This commit removes a few columns from
pg_stat_bgwriter, and introduces pg_stat_checkpointer with equivalent,
renamed columns (plus a new one for the reset timestamp):
- checkpoints_timed -> num_timed
- checkpoints_req -> num_requested
- checkpoint_write_time -> write_time
- checkpoint_sync_time -> sync_time
- buffers_checkpoint -> buffers_written
The fields of PgStat_CheckpointerStats and its SQL functions are renamed
to match with the new field names, for consistency. Note that
background writer and checkpointer have been split into two different
processes in commits 806a2aee37 and bf405ba8e4. The pgstat
structures were already split, making this change straight-forward.
Bump catalog version.
Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Andres Freund, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACVxX2ii=66RypXRweZe2EsBRiPMj0aHfRfHUeXJcC7kHg@mail.gmail.com
This commit refactors find_tabstat_entry() so as transaction counters
for inserted, updated and deleted tuples are included in the result
returned. If a shared entry is found for a relation, its result is now
a copy of the PgStat_TableStatus entry retrieved from shared memory.
This idea has been proposed by Andres Freund.
While on it, the following SQL functions, used in system views, are
refactored with macros, in the same spirit as 83a1a1b566, reducing the
amount of code:
- pg_stat_get_xact_tuples_deleted()
- pg_stat_get_xact_tuples_inserted()
- pg_stat_get_xact_tuples_updated()
There is now only one caller of find_tabstat_entry() in the tree.
Author: Bertrand Drouvot
Discussion: https://postgr.es/m/b9e1f543-ee93-8168-d530-d961708ad9d3@gmail.com
The original code did very little to guard against integer or floating
point overflow when computing the interval's fields. Detect any such
overflows and error out, rather than silently returning bogus results.
Joseph Koshakow, reviewed by Ashutosh Bapat and me.
Discussion: https://postgr.es/m/CAAvxfHcm1TPwH_zaGWuFoL8pZBestbRZTU6Z%3D-RvAdSXTPbKfg%40mail.gmail.com
Two attributes related to checkpointer statistics are removed in this
commit:
- buffers_backend, that counts the number of buffers written directly by
a backend.
- buffers_backend_fsync, that counts the number of times a backend had
to do fsync() by its own.
These are actually not checkpointer properties but backend properties.
Also, pg_stat_io provides a more accurate and equivalent report of these
numbers, by tracking all the I/O stats related to backends, including
writes and fsyncs, so storing them in pg_stat_checkpointer was
redundant.
Thanks also to Robert Haas and Amit Kapila for their input.
Bump catalog version.
Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Andres Freund
Discussion: https://postgr.es/m/20230210004604.mcszbscsqs3bc5nx@awork3.anarazel.de
f0efa5aec added initReadOnlyStringInfo to allow a StringInfo to be
initialized from an existing buffer and also relaxed the requirement
that a StringInfo's buffer must be NUL terminated at data[len]. Now
that we have that, there's no need for these aggregate deserial
functions to use appendBinaryStringInfo() as that rather wastefully
palloc'd a new buffer and memcpy'd in the bytea's buffer. Instead, we can
just use the bytea's buffer and point the StringInfo directly to that
using the new initializer function.
In Amdahl's law, this speeds up the serial portion of parallel
aggregates and makes sum(numeric), avg(numeric), var_pop(numeric),
var_samp(numeric), variance(numeric), stddev_pop(numeric),
stddev_samp(numeric), stddev(numeric), array_agg(anyarray),
string_agg(text) and string_agg(bytea) scale better in parallel queries.
Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvr%3De-YOigriSHHm324a40HPqcUhSp6pWWgjz5WwegR%3DcQ%40mail.gmail.com
Since C99, there can be a trailing comma after the last value in an
enum definition. A lot of new code has been introducing this style on
the fly. Some new patches are now taking an inconsistent approach to
this. Some add the last comma on the fly if they add a new last
value, some are trying to preserve the existing style in each place,
some are even dropping the last comma if there was one. We could
nudge this all in a consistent direction if we just add the trailing
commas everywhere once.
I omitted a few places where there was a fixed "last" value that will
always stay last. I also skipped the header files of libpq and ecpg,
in case people want to use those with older compilers. There were
also a small number of cases where the enum type wasn't used anywhere
(but the enum values were), which ended up confusing pgindent a bit,
so I left those alone.
Discussion: https://www.postgresql.org/message-id/flat/386f8c45-c8ac-4681-8add-e3b0852c1620%40eisentraut.org
There were various places in our codebase which conjured up a StringInfo
by manually assigning the StringInfo fields and setting the data field
to point to some existing buffer. There wasn't much consistency here as
to what fields like maxlen got set to and in one location we didn't
correctly ensure that the buffer was correctly NUL terminated at len
bytes, as per what was documented as required in stringinfo.h
Here we introduce 2 new functions to initialize StringInfos. One allows
callers to initialize a StringInfo passing along a buffer that is
already allocated by palloc. Here the StringInfo code uses this buffer
directly rather than doing any memcpying into a new allocation. Having
this as a function allows us to verify the buffer is correctly NUL
terminated. StringInfos initialized this way can be appended to and
reset just like any other normal StringInfo.
The other new initialization function also accepts an existing buffer,
but the given buffer does not need to be a pointer to a palloc'd chunk.
This buffer could be a pointer pointing partway into some palloc'd chunk
or may not even be palloc'd at all. StringInfos initialized this way
are deemed as "read-only". This means that it's not possible to
append to them or reset them.
For the latter of the two new initialization functions mentioned above,
we relax the requirement that the data buffer must be NUL terminated.
Relaxing this requirement is convenient in a few places as it can save
us from having to allocate an entire new buffer just to add the NUL
terminator or save us from having to temporarily add a NUL only to have to
put the original char back again later.
Incompatibility note:
Here we also forego adding the NUL in a few places where it does not
seem to be required. These locations are passing the given StringInfo
into a type's receive function. It does not seem like any of our
built-in receive functions require this, but perhaps there's some UDT
out there in the wild which does require this. It is likely worthy of
a mention in the release notes that a UDT's receive function mustn't rely
on the input StringInfo being NUL terminated.
Author: David Rowley
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAApHDvorfO3iBZ%3DxpiZvp3uHtJVLyFaPBSvcAhAq2HPLnaNSwQ%40mail.gmail.com
While reading information from the old cluster, a list of logical
slots is fetched. At the later part of upgrading, pg_upgrade revisits the
list and restores slots by executing pg_create_logical_replication_slot()
on the new cluster. Migration of logical replication slots is only
supported when the old cluster is version 17.0 or later.
If the old node has invalid slots or slots with unconsumed WAL records,
the pg_upgrade fails. These checks are needed to prevent data loss.
The significant advantage of this commit is that it makes it easy to
continue logical replication even after upgrading the publisher node.
Previously, pg_upgrade allowed copying publications to a new node. With
this patch, adjusting the connection string to the new publisher will
cause the apply worker on the subscriber to connect to the new publisher
automatically. This enables seamless continuation of logical replication,
even after an upgrade.
Author: Hayato Kuroda, Hou Zhijie
Reviewed-by: Peter Smith, Bharath Rupireddy, Dilip Kumar, Vignesh C, Shlok Kyal
Discussion: http://postgr.es/m/TYAPR01MB58664C81887B3AF2EB6B16E3F5939@TYAPR01MB5866.jpnprd01.prod.outlook.com
Discussion: http://postgr.es/m/CAA4eK1+t7xYcfa0rEQw839=b2MzsfvYDPz3xbD+ZqOdP3zpKYg@mail.gmail.com
The Self Join Elimination (SJE) feature removes an inner join of a plain table
to itself in the query tree if is proved that the join can be replaced with
a scan without impacting the query result. Self join and inner relation are
replaced with the outer in query, equivalence classes, and planner info
structures. Also, inner restrictlist moves to the outer one with removing
duplicated clauses. Thus, this optimization reduces the length of the range
table list (this especially makes sense for partitioned relations), reduces
the number of restriction clauses === selectivity estimations, and potentially
can improve total planner prediction for the query.
The SJE proof is based on innerrel_is_unique machinery.
We can remove a self-join when for each outer row:
1. At most one inner row matches the join clause.
2. Each matched inner row must be (physically) the same row as the outer one.
In this patch we use the next approach to identify a self-join:
1. Collect all merge-joinable join quals which look like a.x = b.x
2. Add to the list above the baseretrictinfo of the inner table.
3. Check innerrel_is_unique() for the qual list. If it returns false, skip
this pair of joining tables.
4. Check uniqueness, proved by the baserestrictinfo clauses. To prove
the possibility of self-join elimination inner and outer clauses must have
an exact match.
The relation replacement procedure is not trivial and it is partly combined
with the one, used to remove useless left joins. Tests, covering this feature,
were added to join.sql. Some regression tests changed due to self-join removal
logic.
Discussion: https://postgr.es/m/flat/64486b0b-0404-e39e-322d-0801154901f3%40postgrespro.ru
Author: Andrey Lepikhov, Alexander Kuzmenkov
Reviewed-by: Tom Lane, Robert Haas, Andres Freund, Simon Riggs, Jonathan S. Katz
Reviewed-by: David Rowley, Thomas Munro, Konstantin Knizhnik, Heikki Linnakangas
Reviewed-by: Hywel Carver, Laurenz Albe, Ronan Dunklau, vignesh C, Zhihong Yu
Reviewed-by: Greg Stark, Jaime Casanova, Michał Kłeczek, Alena Rybakina
Reviewed-by: Alexander Korotkov
Previously, ALTER SYSTEM failed if the target GUC wasn't present in
the session's GUC hashtable. That is a reasonable behavior for core
(single-part) GUC names, and for custom GUCs for which we have loaded
an extension that's reserved the prefix. But it's unnecessarily
restrictive otherwise, and it also causes inconsistent behavior:
you can "ALTER SYSTEM SET foo.bar" only if you did "SET foo.bar"
earlier in the session. That's fairly silly.
Hence, refactor things so that we can execute ALTER SYSTEM even
if the variable doesn't have a GUC hashtable entry, as long as the
name meets the custom-variable naming requirements and does not
have a reserved prefix. (It's safe to do this even if the
variable belongs to an extension we currently don't have loaded.
A bad value will at worst cause a WARNING when the extension
does get loaded.)
Also, adjust GRANT ON PARAMETER to have the same opinions about
whether to allow an unrecognized GUC name, and to throw the
same errors if not (it previously used a one-size-fits-all
message for several distinguishable conditions). By default,
only a superuser will be allowed to do ALTER SYSTEM SET on an
unrecognized name, but it's possible to GRANT the ability to
do it.
Patch by me, pursuant to a documentation complaint from
Gavin Panella. Arguably this is a bug fix, but given the
lack of other complaints I'll refrain from back-patching.
Discussion: https://postgr.es/m/2617358.1697501956@sss.pgh.pa.us
Discussion: https://postgr.es/m/169746329791.169914.16613647309012285391@wrigleys.postgresql.org
There was no I/O timing statistics for counting read and write timings
on local blocks, contrary to the counterparts for temp and shared
blocks. This information is available when track_io_timing is enabled.
The output of EXPLAIN is updated to show this information. An update of
pg_stat_statements is planned next.
Author: Nazir Bilal Yavuz
Reviewed-by: Robert Haas, Melanie Plageman
Discussion: https://postgr.es/m/CAN55FZ19Ss279mZuqGbuUNxka0iPbLgYuOQXqAKewrjNrp27VA@mail.gmail.com
These two counters, defined in BufferUsage to track respectively the
time spent while reading and writing blocks have historically only
tracked data related to shared buffers, when track_io_timing is enabled.
An upcoming patch to add specific counters for local buffers will take
advantage of this rename as it has come up that no data is currently
tracked for local buffers, and tracking local and shared buffers using
the same fields would be inconsistent with the treatment done for temp
buffers. Renaming the existing fields clarifies what the block type of
each stats field is.
pg_stat_statement is updated to reflect the rename. No extension
version bump is required as 5a3423ad8e has done one, affecting v17~.
Author: Nazir Bilal Yavuz
Reviewed-by: Robert Haas, Melanie Plageman
Discussion: https://postgr.es/m/CAN55FZ19Ss279mZuqGbuUNxka0iPbLgYuOQXqAKewrjNrp27VA@mail.gmail.com
Relation files extended by multiple blocks at a time have been counting
the number of blocks written, but forgot to increment the write time in
this case, as single-block write and relation extension are treated as
two different I/O operations in the shared stats: IOOP_EXTEND vs
IOOP_WRITE. In this case IOOP_EXTEND was forgotten for normal
(non-temporary) relations, still the number of blocks written was
incremented according to the relation extend done.
Write times are tracked when track_io_timing is enabled, which is not
the case by default.
Author: Nazir Bilal Yavuz
Reviewed-by: Robert Haas, Melanie Plageman
Discussion: https://postgr.es/m/CAN55FZ19Ss279mZuqGbuUNxka0iPbLgYuOQXqAKewrjNrp27VA@mail.gmail.com
Backpatch-through: 16
Use a modulo operator instead of implementing the same behavior
with a loop. The loop solution is doubtless microscopically
faster for the typical case of only wrapping into the very next
day, but maybe not so much for large interval values. In any
case, timetz is such a backwater that it's doubtful anybody
would notice any performance change anyway.
This avoids a compiler bug occurring in AIX's xlc, even in pretty
late-model revisions.
We did not have test coverage for the case where the initial
result->time value is negative, so add that.
For the moment, install this only in HEAD. My plan is to
back-patch the test case, and then the code change assuming that
buildfarm testing proves the bug occurs in the back branches.
(That seems pretty likely, but let's find out for sure.)
Per buildfarm results from commits 97957fdba and 2f0472030.
Thanks to Michael Paquier for the idea to use a modulo operation
to replace the faulty loop.
Discussion: https://postgr.es/m/CA+hUKGK=DOC+hE-62FKfZy=Ybt5uLkrg3zCZD-jFykM-iPn8yw@mail.gmail.com
The SIGTERM handler for the startup process immediately calls
proc_exit() for the duration of the restore_command, i.e., a call
to system(). This system() call forks a new process to execute the
shell command, and this child process inherits the parent's signal
handlers. If both the parent and child processes receive SIGTERM,
both will attempt to call proc_exit(). This can end badly. For
example, both processes will try to remove themselves from the
PGPROC shared array.
To fix this problem, this commit adds a check in
StartupProcShutdownHandler() to see whether MyProcPid == getpid().
If they match, this is the parent process, and we can proc_exit()
like before. If they do not match, this is a child process, and we
just emit a message to STDERR (in a signal safe manner) and
_exit(), thereby skipping any problematic exit callbacks.
This commit also adds checks in proc_exit(), ProcKill(), and
AuxiliaryProcKill() that verify they are not being called within
such child processes.
Suggested-by: Andres Freund
Reviewed-by: Thomas Munro, Andres Freund
Discussion: https://postgr.es/m/Y9nGDSgIm83FHcad%40paquier.xyz
Discussion: https://postgr.es/m/20230223231503.GA743455%40nathanxps13
Backpatch-through: 11
This commit introduces trigger on login event, allowing to fire some actions
right on the user connection. This can be useful for logging or connection
check purposes as well as for some personalization of environment. Usage
details are described in the documentation included, but shortly usage is
the same as for other triggers: create function returning event_trigger and
then create event trigger on login event.
In order to prevent the connection time overhead when there are no triggers
the commit introduces pg_database.dathasloginevt flag, which indicates database
has active login triggers. This flag is set by CREATE/ALTER EVENT TRIGGER
command, and unset at connection time when no active triggers found.
Author: Konstantin Knizhnik, Mikhail Gribkov
Discussion: https://postgr.es/m/0d46d29f-4558-3af9-9c85-7774e14a7709%40postgrespro.ru
Reviewed-by: Pavel Stehule, Takayuki Tsunakawa, Greg Nancarrow, Ivan Panchenko
Reviewed-by: Daniel Gustafsson, Teodor Sigaev, Robert Haas, Andres Freund
Reviewed-by: Tom Lane, Andrey Sokolov, Zhihong Yu, Sergey Shinderuk
Reviewed-by: Gregory Stark, Nikita Malakhov, Ted Yu
Commit dc7d70ea added functions that read the control file, but didn't
acquire ControlFileLock. With unlucky timing, file systems that have
weak interlocking like ext4 and ntfs could expose partially overwritten
contents, and the checksum would fail.
Back-patch to all supported releases.
Reviewed-by: David Steele <david@pgmasters.net>
Reviewed-by: Anton A. Melnikov <aamelnikov@inbox.ru>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/20221123014224.xisi44byq3cf5psi%40awork3.anarazel.de
Bruce Momjian
Dean Rasheed
Tom Lane
Michael Paquier
Nathan Bossart
Heikki Linnakangas
Peter Eisentraut
Amit Kapila
David Rowley
Alvaro Herrera
Noah Misch
Daniel Gustafsson
Jeff Davis
Alexander Korotkov
Thomas Munro