To deparse a reference to a field of a RECORD-type output of a
subquery, EXPLAIN normally digs down into the subquery's plan to try
to discover exactly which anonymous RECORD type is meant. However,
this can fail if the subquery has been optimized out of the plan
altogether on the grounds that no rows could pass the WHERE quals,
which has been possible at least since 3fc6e2d7f. There isn't
anything remaining in the plan tree that would help us, so fall back
to printing the field name as "fN" for the N'th column of the record.
(This will actually be the right thing some of the time, since it
matches the column names we assign to RowExprs.)
In passing, fix a comment typo in create_projection_plan, which
I noticed while experimenting with an alternative fix for this.
Per bug #18576 from Vasya B. Back-patch to all supported branches.
Richard Guo and Tom Lane
Discussion: https://postgr.es/m/18576-9feac34e132fea9e@postgresql.org
This used to be part of CREATE OPERATOR CLASS and ALTER OPERATOR
FAMILY, but it has done nothing (except issue a NOTICE) since
PostgreSQL 8.4. Commit 30e7c175b8 removed support for dumping from
pre-9.2 servers, so this no longer serves any need.
This now removes it completely, and you'd get a normal parse error if
you used it.
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/113ef2d2-3657-4353-be97-f28fceddbca1%40eisentraut.org
The apply worker was using XactLastCommitEnd as local end_lsn for applying
prepare and rollback_prepare. The XactLastCommitEnd value is the end lsn
of the last commit applied before the prepare transaction which makes no
sense. This LSN is used to decide whether we can send the acknowledgment
of the corresponding remote LSN to the server.
It is okay not to set the local_end LSN with the actual WAL position for
the prepare because we always flush the prepare record. So, we can send
the acknowledgment of the remote_end LSN as soon as prepare is finished.
The current code is misleading but as such doesn't create any problem, so
decided not to backpatch.
Author: Hayato Kuroda
Reviewed-by: Shveta Malik, Amit Kapila
Discussion: https://postgr.es/m/TYAPR01MB5692FA4926754B91E9D7B5F0F5AA2@TYAPR01MB5692.jpnprd01.prod.outlook.com
In future commits we're going to trace authentication related messages.
Some of these messages contain challenge bytes as part of a
challenge-response flow. Since these bytes are different for every
connection, we want to normalize them when the PQTRACE_REGRESS_MODE
trace flag is set. This commit modifies pqTraceOutputNchar to take a
suppress argument, which makes it possible to do so.
Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com
Trying to attach a table as a partition which is already on the
referenced side of a foreign key on the partitioned table that it is
being attached to, leads to strange behavior: we try to clone the
foreign key from the parent to the partition, but this new FK points to
the partition itself, and the mix of pg_constraint rows and triggers
doesn't behave well.
Rather than trying to untangle the mess (which might be possible given
sufficient time), I opted to forbid the ATTACH. This doesn't seem a
problematic restriction, given that we already fail to create the
foreign key if you do it the other way around, that is, having the
partition first and the FK second.
Backpatch to all supported branches.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/18541-628a61bc267cd2d3@postgresql.org
I also took the liberty of changing
errmsg("COPY DEFAULT only available using COPY FROM")
to
errmsg("COPY %s cannot be used with %s", "DEFAULT", "COPY TO")
because the original wording is unlike all other messages that indicate
option incompatibility. This message was added by commit 9f8377f7a2
(16-era), in whose development thread there was no discussion on this
point.
Backpatch to 17.
getTimelineHistory() is called twice, to read the source and the
target timeline history files. However, the loop to print the file
with the --debug option used the wrong variable when dealing with the
source. As a result, the source's history was always printed as empty.
Spotted while debugging bug #18575, but this does not fix that bug,
just the debugging output. Backpatch to all supported versions.
Discussion: https://www.postgresql.org/message-id/092dd515-b7b4-4fd0-8407-ceca2f02f6ec@iki.fi
If the plancache entry for the CALL statement is already stale,
it's possible for us to fetch an old procedure OID out of it,
and then fail with "cache lookup failed for function NNN".
In ordinary usage this never happens because make_callstmt_target
is called just once immediately after building the plancache
entry. It can be forced however by setting up an erroneous CALL
(that causes make_callstmt_target itself to report an error),
then dropping/recreating the target procedure, then repeating
the erroneous CALL.
To fix, use SPI_plan_get_cached_plan() to fetch the plancache's
plan, rather than assuming we can use SPI_plan_get_plan_sources().
This shouldn't add any noticeable overhead in the normal case,
and in the stale-plan case we'd have had to replan anyway a little
further down.
The other callers of SPI_plan_get_plan_sources() seem OK, because
either they don't need up-to-date plans or they know that the
query was just (re) planned. But add some commentary in hopes
of not falling into this trap again.
Per bug #18574 from Song Hongyu. Back-patch to v14 where this coding
was introduced. (Older branches have comparable code, but it's run
after any required replanning, so there's no issue.)
Discussion: https://postgr.es/m/18574-2ce7ba3249221389@postgresql.org
Make it clear that "astreamer" stands for "archive streamer".
Generalize comments that still believe this code can only be used
by pg_basebackup. Add some comments explaining the asymmetry
between the gzip, lz4, and zstd astreamers, in the hopes of making
life easier for anyone who hacks on this code in the future.
Robert Haas, reviewed by Amul Sul.
Discussion: http://postgr.es/m/CAAJ_b97O2kkKVTWxt8MxDN1o-cDfbgokqtiN2yqFf48=gXpcxQ@mail.gmail.com
Replace a static scratch buffer with a local variable, because a
static buffer makes the function not thread-safe. This function is
used in client-code in libpq, so it needs to be thread-safe. It was
until commit b67b57a966, which replaced the implementation with the
one from pgcrypto.
Backpatch to v14, where we switched to the new implementation.
Reviewed-by: Robert Haas, Michael Paquier
Discussion: https://www.postgresql.org/message-id/dfa2015d-ad21-4802-a4cc-3850fc5fff3f@iki.fi
Commit 0b9466fce added a dependency on fe_memutils' pnstrdup() inside
informix.c. This adds an exit() path in a library, which we don't
want. (Unlike libpq, the ecpg libraries don't have an automated check
for that, but it makes sense to keep them to a similar standard.) The
ecpg code can already handle failure results from the *strdup() call
by itself.
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/CAOYmi+=pg=W5L1h=3MEP_EB24jaBu2FyATrLXqQHGe7cpuvwyg@mail.gmail.com
These callbacks are receiving hash values as arguments, which doesn't allow
direct lookups for AttoptCacheHash and TypeCacheHash. This is why subject
callbacks currently use full iteration over corresponding hashes.
This commit avoids full hash iteration in InvalidateAttoptCacheCallback(),
and TypeCacheTypCallback(). At first, we switch AttoptCacheHash and
TypeCacheHash to use same hash function as syscache. As second, we
use hash_seq_init_with_hash_value() to iterate only hash entries with matching
hash value.
Discussion: https://postgr.es/m/5812a6e5-68ae-4d84-9d85-b443176966a1%40sigaev.ru
Author: Teodor Sigaev
Reviewed-by: Aleksander Alekseev, Tom Lane, Michael Paquier, Roman Zharkov
Reviewed-by: Andrei Lepikhov
This new function iterates hash entries with given hash values. This function
is designed to avoid full sequential hash search in the syscache invalidation
callbacks.
Discussion: https://postgr.es/m/5812a6e5-68ae-4d84-9d85-b443176966a1%40sigaev.ru
Author: Teodor Sigaev
Reviewed-by: Aleksander Alekseev, Tom Lane, Michael Paquier, Roman Zharkov
Reviewed-by: Andrei Lepikhov
The buffer allocation was correct, but looked archaic and scary:
- It was weird to calculate the buffer size before determining which
format string was used. With the same effort, we could've used the
right-sized buffer for each branch.
- Commit aa0d350456 added one more possible return string ("all true
bits"), but didn't adjust the code at the top of the function to
calculate the returned string's max size. It was not a live bug,
because the new string was smaller than the existing ones, but
seemed wrong in principle.
- Use of sprintf() is generally eyebrow-raising these days
Switch to psprintf(). psprintf() allocates a larger buffer than what
was allocated before, 128 bytes vs 80 bytes, which is acceptable as
this code is not performance or space critical.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/54c29fb0-edf2-48ea-9814-44e918bbd6e8@iki.fi
I started by marking VoidString as const, and fixing the fallout by
marking more fields and function arguments as const. It proliferated
quite a lot, but all within spell.c and spell.h.
A more narrow patch to get rid of the static VoidString buffer would
be to replace it with '#define VoidString ""', as C99 allows assigning
"" to a non-const pointer, even though you're not allowed to modify
it. But it seems like good hygiene to mark all these as const. In the
structs, the pointers can point to the constant VoidString, or a
buffer allocated with palloc(), or with compact_palloc(), so you
should not modify them.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/54c29fb0-edf2-48ea-9814-44e918bbd6e8@iki.fi
There was no need for these to be static buffers, local variables work
just as well. I think they were marked as 'static' to imply that they
are read-only, but 'const' is more appropriate for that, so change
them to const.
To make it possible to mark the variables as 'const', also add 'const'
decorations to the transformRelOptions() signature.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/54c29fb0-edf2-48ea-9814-44e918bbd6e8@iki.fi
pg_strxfrm() takes a pg_locale_t, so it works properly with all
providers. This improves estimates for ICU when performing linear
interpolation within a histogram bin.
Previously, convert_string_datum() always used strxfrm() and relied on
setlocale(). That did not produce good estimates for non-default or
non-libc collations.
Discussion: https://postgr.es/m/89475ee5487d795124f4e25118ea8f1853edb8cb.camel@j-davis.com
Parallel workers failed after a sequence like
BEGIN;
CREATE USER foo;
SET SESSION AUTHORIZATION foo;
because check_session_authorization could not see the uncommitted
pg_authid row for "foo". This is because we ran RestoreGUCState()
in a separate transaction using an ordinary just-created snapshot.
The same disease afflicts any other GUC that requires catalog lookups
and isn't forgiving about the lookups failing.
To fix, postpone RestoreGUCState() into the worker's main transaction
after we've set up a snapshot duplicating the leader's. This affects
check_transaction_isolation and check_transaction_deferrable, which
think they should only run during transaction start. Make them
act like check_transaction_read_only, which already knows it should
silently accept the value when InitializingParallelWorker.
This un-reverts commit f5f30c22e. The original plan was to back-patch
that, but the fact that 0ae5b763e proved to be a pre-requisite shows
that the subtle API change for GUC hooks might actually break some of
them. The problem we're trying to fix seems not worth taking such a
risk for in stable branches.
Per bug #18545 from Andrey Rachitskiy.
Discussion: https://postgr.es/m/18545-feba138862f19aaa@postgresql.org
The previous coding here threw an error from assign_client_encoding
if it was invoked in a parallel worker. That's a very fundamental
violation of the GUC hook API: assign hooks must not throw errors.
The place to complain is in the check hook, so move the test to
there, and use the regular check-hook API (ie return false) to
report it.
The reason this coding is a problem is that it breaks GUC rollback,
which may occur after we leave InitializingParallelWorker state.
That case seems not actually reachable before now, but commit
f5f30c22e made it reachable, so we need to fix this before that
can be un-reverted.
In passing, improve the commentary in ParallelWorkerMain, and
add a check for failure of SetClientEncoding. That's another
case that can't happen now but might become possible after
foreseeable code rearrangements (notably, if the shortcut of
skipping PrepareClientEncoding stops being OK).
Discussion: https://postgr.es/m/18545-feba138862f19aaa@postgresql.org
Prior to commit 0709b7ee72, which changed the spinlock primitives
to function as compiler barriers, access to variables within a
spinlock-protected section required using a volatile pointer, but
that is no longer necessary.
Reviewed-by: Bertrand Drouvot, Michael Paquier
Discussion: https://postgr.es/m/Zqkv9iK7MkNS0KaN%40nathan
Previously, passing NULL for pg_locale_t meant "use the libc provider
and the server environment". Now that the database collation is
represented as a proper pg_locale_t (not dependent on setlocale()),
remove special cases for NULL.
Leave wchar2char() and char2wchar() unchanged for now, because the
callers don't always have a libc-based pg_locale_t available.
Discussion: https://postgr.es/m/cfd9eb85-c52a-4ec9-a90e-a5e4de56e57d@eisentraut.org
Reviewed-by: Peter Eisentraut, Andreas Karlsson
Unlike the rest of the astreamer (formerly bbstreamer) infrastructure
which is reusable by other tools, astreamer_inject.c seems extremely
specific to pg_basebackup. Hence, move the corresponding declarations
to a separate header file, so that we can move the rest of the code
without moving this.
Amul Sul, reviewed by Sravan Kumar and by me.
Discussion: http://postgr.es/m/CAAJ_b94StvLWrc_p4q-f7n3OPfr6GhL8_XuAg2aAaYZp1tF-nw@mail.gmail.com
I (rhaas) intended "bbstreamer" to stand for "base backup streamer,"
but that implies that this infrastructure can only ever be used by
pg_basebackup. In fact, it is a generally useful way of streaming
data from a tar or compressed tar file, and it could be extended to
work with other archive formats as well if we ever wanted to do that.
Hence, rename it to "astreamer" (archive streamer) in preparation for
reusing the infrastructure from pg_verifybackup (and perhaps
eventually also other utilities, such as pg_combinebackup or
pg_waldump).
This is purely a renaming commit. Comment adjustments and relocation
of the actual code to someplace from which it can be reused are left
to future commits.
Amul Sul, reviewed by Sravan Kumar and by me.
Discussion: http://postgr.es/m/CAAJ_b94StvLWrc_p4q-f7n3OPfr6GhL8_XuAg2aAaYZp1tF-nw@mail.gmail.com
When pg_dump retrieves the list of database objects and performs the
data dump, there was possibility that objects are replaced with others
of the same name, such as views, and access them. This vulnerability
could result in code execution with superuser privileges during the
pg_dump process.
This issue can arise when dumping data of sequences, foreign
tables (only 13 or later), or tables registered with a WHERE clause in
the extension configuration table.
To address this, pg_dump now utilizes the newly introduced
restrict_nonsystem_relation_kind GUC parameter to restrict the
accesses to non-system views and foreign tables during the dump
process. This new GUC parameter is added to back branches too, but
these changes do not require cluster recreation.
Back-patch to all supported branches.
Reviewed-by: Noah Misch
Security: CVE-2024-7348
Backpatch-through: 12
Here we adjust escape_json_with_len() to make use of SIMD to allow
processing of up to 16-bytes at a time rather than processing a single
byte at a time. This has been shown to speed up escaping of JSON
strings significantly.
Escaping is required for both JSON string properties and also the
property names themselves, so this should also help improve the speed of
the conversion from JSON into text for JSON objects that have property
names 16 or more bytes long.
Escaping JSON strings was often a significant bottleneck for longer
strings. With these changes, some benchmarking has shown a query
performing nearly 4 times faster when escaping a JSON object with a 1MB
text property. Tests with shorter text properties saw smaller but still
significant performance improvements. For example, a test outputting 1024
JSON strings with a text property length ranging from 1 char to 1024 chars
became around 2 times faster.
Author: David Rowley
Reviewed-by: Melih Mutlu
Discussion: https://postgr.es/m/CAApHDvpLXwMZvbCKcdGfU9XQjGCDm7tFpRdTXuB9PVgpNUYfEQ@mail.gmail.com
Like 75534436a4, this acts mainly as a template to show what can be
achieved with fixed-numbered stats (like WAL, bgwriter, etc.) with the
pluggable cumulative statistics APIs introduced in 7949d95945.
Fixed-numbered stats are defined in their own file, named
injection_stats_fixed.c, separated entirely from the variable-numbered
case in injection_stats.c. This is mainly for clarity as having both
examples in the same file would be confusing.
Note that this commit uses the helper routines added in 2eff9e678d.
The stats stored track globally the number of times injection points
have been attached, detached or run. Two more fields should be added
later for the number of times a point has been cached or loaded, but
what's here is enough as a template.
More TAP tests are added, providing coverage for fixed-numbered custom
stats.
Author: Michael Paquier
Reviewed-by: Dmitry Dolgov, Bertrand Drouvot
Discussion: https://postgr.es/m/Zmqm9j5EO0I4W8dx@paquier.xyz
This acts as a template of what can be achieved with the pluggable
cumulative stats APIs introduced in 7949d95945 for the
variable-numbered case where stats entries are stored in the pgstats
dshash, while being potentially useful on its own for injection points,
say to add starting and/or stopping conditions based on the statistics
(want to trigger a callback after N calls, for example?).
Currently, the only data gathered is the number of times an injection
point is run. More fields can always be added as required. All the
routines related to the stats are located in their own file, called
injection_stats.c in the test module injection_points, for clarity.
The stats can be used only if the test module is loaded through
shared_preload_libraries. The key of the dshash uses InvalidOid for the
database, and an int4 hash of the injection point name as object ID.
A TAP test is added to provide coverage for the new custom cumulative
stats APIs, showing the persistency of the data across restarts, for
example.
Author: Michael Paquier
Reviewed-by: Dmitry Dolgov, Bertrand Drouvot
Discussion: https://postgr.es/m/Zmqm9j5EO0I4W8dx@paquier.xyz
This is useful for extensions to get snapshot and shmem data for custom
cumulative statistics when these have a fixed number of objects, so as
these do not need to know about the snapshot internals, aka pgStatLocal.
An upcoming commit introducing an example template for custom cumulative
stats with fixed-numbered objects will make use of these. I have
noticed that this is useful for extension developers while hacking my
own example, actually.
Author: Michael Paquier
Reviewed-by: Dmitry Dolgov, Bertrand Drouvot
Discussion: https://postgr.es/m/Zmqm9j5EO0I4W8dx@paquier.xyz
This commit adds support in the backend for $subject, allowing
out-of-core extensions to plug their own custom kinds of cumulative
statistics. This feature has come up a few times into the lists, and
the first, original, suggestion came from Andres Freund, about
pg_stat_statements to use the cumulative statistics APIs in shared
memory rather than its own less efficient internals. The advantage of
this implementation is that this can be extended to any kind of
statistics.
The stats kinds are divided into two parts:
- The in-core "builtin" stats kinds, with designated initializers, able
to use IDs up to 128.
- The "custom" stats kinds, able to use a range of IDs from 128 to 256
(128 slots available as of this patch), with information saved in
TopMemoryContext. This can be made larger, if necessary.
There are two types of cumulative statistics in the backend:
- For fixed-numbered objects (like WAL, archiver, etc.). These are
attached to the snapshot and pgstats shmem control structures for
efficiency, and built-in stats kinds still do that to avoid any
redirection penalty. The data of custom kinds is stored in a first
array in snapshot structure and a second array in the shmem control
structure, both indexed by their ID, acting as an equivalent of the
builtin stats.
- For variable-numbered objects (like tables, functions, etc.). These
are stored in a dshash using the stats kind ID in the hash lookup key.
Internally, the handling of the builtin stats is unchanged, and both
fixed and variabled-numbered objects are supported. Structure
definitions for builtin stats kinds are renamed to reflect better the
differences with custom kinds.
Like custom RMGRs, custom cumulative statistics can only be loaded with
shared_preload_libraries at startup, and must allocate a unique ID
shared across all the PostgreSQL extension ecosystem with the following
wiki page to avoid conflicts:
https://wiki.postgresql.org/wiki/CustomCumulativeStats
This makes the detection of the stats kinds and their handling when
reading and writing stats much easier than, say, allocating IDs for
stats kinds from a shared memory counter, that may change the ID used by
a stats kind across restarts. When under development, extensions can
use PGSTAT_KIND_EXPERIMENTAL.
Two examples that can be used as templates for fixed-numbered and
variable-numbered stats kinds will be added in some follow-up commits,
with tests to provide coverage.
Some documentation is added to explain how to use this plugin facility.
Author: Michael Paquier
Reviewed-by: Dmitry Dolgov, Bertrand Drouvot
Discussion: https://postgr.es/m/Zmqm9j5EO0I4W8dx@paquier.xyz
Otherwise, this would break if using C and C++ compilers from
different families and they understand different options. It already
used the right flags for compiling, this is only for linking. Also,
the meson setup already did this correctly.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/228700.1722717983@sss.pgh.pa.us
These should have been switched from %d to %u in 3188a4582a in the
debugging elogs added in ca1ba50fcb. PgStat_Kind should never be
higher than INT32_MAX, but let's be clean.
Issue noticed while hacking more on this area.
This warning flag detects global variables not declared in header
files. This is similar to what -Wmissing-prototypes does for
functions. (More correctly, it is similar to what
-Wmissing-declarations does for functions, but -Wmissing-prototypes is
a superset of that in C.)
This flag is new in GCC 14. Clang has supported it for a while.
Several recent commits have cleaned up warnings triggered by this, so
it should now be clean.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/e0a62134-83da-4ba4-8cdb-ceb0111c95ce@eisentraut.org
Since commit 4b74ebf726, the refresh logic is used to populate
materialized views, so we can simplify the error message in
ExecCreateTableAs().
Also, RefreshMatViewByOid() is moved to just after
create_ctas_nodata() call to improve code readability.
Author: Yugo Nagata
Discussion: https://postgr.es/m/20240802161301.d975daca9ba7a706fa05ecd7@sraoss.co.jp
pg_wal_replay_wait() is to be used on standby and specifies waiting for
the specific WAL location to be replayed. This option is useful when
the user makes some data changes on primary and needs a guarantee to see
these changes are on standby.
The queue of waiters is stored in the shared memory as an LSN-ordered pairing
heap, where the waiter with the nearest LSN stays on the top. During
the replay of WAL, waiters whose LSNs have already been replayed are deleted
from the shared memory pairing heap and woken up by setting their latches.
pg_wal_replay_wait() needs to wait without any snapshot held. Otherwise,
the snapshot could prevent the replay of WAL records, implying a kind of
self-deadlock. This is why it is only possible to implement
pg_wal_replay_wait() as a procedure working without an active snapshot,
not a function.
Catversion is bumped.
Discussion: https://postgr.es/m/eb12f9b03851bb2583adab5df9579b4b%40postgrespro.ru
Author: Kartyshov Ivan, Alexander Korotkov
Reviewed-by: Michael Paquier, Peter Eisentraut, Dilip Kumar, Amit Kapila
Reviewed-by: Alexander Lakhin, Bharath Rupireddy, Euler Taveira
Reviewed-by: Heikki Linnakangas, Kyotaro Horiguchi
Before Bison 3.4, the generated parser implementation files run afoul
of -Wmissing-variable-declarations (in spite of commit ab61c40bfa)
because declarations for yylval and possibly yylloc are missing. The
generated header files contain an extern declaration, but the
implementation files don't include the header files. Since Bison 3.4,
the generated implementation files automatically include the generated
header files, so then it works.
To make this work with older Bison versions as well, include the
generated header file from the .y file.
(With older Bison versions, the generated implementation file contains
effectively a copy of the header file pasted in, so including the
header file is redundant. But we know this works anyway because the
core grammar uses this arrangement already.)
Discussion: https://www.postgresql.org/message-id/flat/e0a62134-83da-4ba4-8cdb-ceb0111c95ce@eisentraut.org
Tom Lane