If a MERGE command contains WHEN NOT MATCHED BY SOURCE actions, the
merge join condition is used by the executor to distinguish MATCHED
from NOT MATCHED BY SOURCE cases. However, this qual is executed using
the output from the join subplan node, which nulls the output from the
source relation in the not matched case, and so the result may be
incorrect if the join condition is "non-strict" -- for example,
something like "src.col IS NOT DISTINCT FROM tgt.col".
Fix this by enhancing the join recheck condition with an additional
"src IS NOT NULL" check, so that it does the right thing when
evaluated using the output from the join subplan.
Noted by Tom Lane while investigating bug #18634 from Alexander
Lakhin.
Back-patch to v17, where WHEN NOT MATCHED BY SOURCE support was added
to MERGE.
Discussion: https://postgr.es/m/18634-db5299c937877f2b%40postgresql.org
Use pqParseIntParam (nee parse_int_param) instead of using strtol
directly. This allows trailing whitespace, which the previous coding
didn't, and makes the spelling of the error message consistent with
other similar cases.
This seems to be an oversight in commit e7a221797, which introduced
parse_int_param. That fixed places that were using atoi(), but missed
this place which was randomly using strtol() instead.
Ordinarily I'd consider this minor cleanup not worth back-patching.
However, it seems that ecpg assumes it can add trailing whitespace
to URL parameters, so that use of the keepalives option fails in
that context. Perhaps that's worth improving as a separate matter.
In the meantime, back-patch this to all supported branches.
Yuto Sasaki (some further cleanup by me)
Discussion: https://postgr.es/m/TY2PR01MB36286A7B97B9A15793335D18C1772@TY2PR01MB3628.jpnprd01.prod.outlook.com
The fork name is always separated with the block number by an underscore
in the names of the files generated, but the docs stuck them together
without a separator, which was confusing.
Author: Christoph Berg
Discussion: https://postgr.es/m/ZvxtSLiix9eceMRM@msg.df7cb.de
Backpatch-through: 16
There were unnecessary non-breaking spaces (nbsp, U+00A0, 0xc2a0 in
UTF-8) in the docs. This commit replaces them with ASCII spaces
(0x20).
config.sgml is backpatched through 17.
ref/drop_extension.sgml is backpatched through 13.
Discussion: https://postgr.es/m/20240930.153404.202479334310259810.ishii%40postgresql.org
Reviewed-by: Yugo Nagata, Daniel Gustafsson
Backpatch-through: 17, 13
COMMIT PREPARED removes on-disk 2PC files near its end, but the state
checked if a file is on-disk or not gets read from shared memory while
not holding the two-phase state lock.
Because of that, there was a small window where a second backend doing a
PREPARE TRANSACTION could reuse the GlobalTransaction put back into the
2PC free list by the COMMIT PREPARED, overwriting the "ondisk" flag read
afterwards by the COMMIT PREPARED to decide if its on-disk two-phase
state file should be removed, preventing the file deletion.
This commit fixes this issue so as the "ondisk" flag in the
GlobalTransaction is read while holding the two-phase state lock, not
from shared memory after its entry has been added to the free list.
Orphaned two-phase state files flushed to disk after a checkpoint are
discarded at the beginning of recovery. However, a truncation of
pg_xact/ would make the startup process issue a FATAL when it cannot
read the SLRU page holding the state of the transaction whose 2PC file
was orphaned, which is a necessary step to decide if the 2PC file should
be removed or not. Removing manually the file would be necessary in
this case.
Issue introduced by effe7d9552dd, so backpatch all the way down.
Mea culpa.
Author: wuchengwen
Discussion: https://postgr.es/m/tencent_A7F059B5136A359625C7B2E4A386B3C3F007@qq.com
Backpatch-through: 12
For some reason this listed "-f" and "-w" as valid switches, though
the code doesn't implement any such thing nor do the docs mention
them. The effect of this was that if you tried to use one of these
switches, you'd get an unhelpful error message.
Yusuke Sugie
Discussion: https://postgr.es/m/68e72a2a70f4d84c1c7847b13bcdaef8@oss.nttdata.com
Reindexing temp tables or indexes of other sessions is not allowed.
However, reindexdb in parallel mode previously listed them as
the objects to process, leading to failures.
This commit ensures reindexdb in parallel mode skips temporary tables
and indexes by adding a condition based on the relpersistence column
in pg_class to the object listing queries, preventing these issues.
Note that this commit does not affect reindexdb when temporary tables
or indexes are explicitly specified using the -t or -j options;
reindexdb in that case still does not skip them and can cause an error.
Back-patch to v13 where parallel mode was introduced in reindexdb.
Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/5f37ee56-14fb-44fe-9150-9eb97e10538b@oss.nttdata.com
Defect in last week's commit aac2c9b4fde889d13f859c233c2523345e72d32b,
per Coverity. Reaching this would need catalog corruption. Back-patch
to v12, like that commit.
Since v17, CREATE MATERIALIZED VIEW has set search_path to
"pg_catalog, pg_temp" while running the query. The docs for the
other commands that restrict search_path mention it, but the page
for CREATE MATERIALIZED VIEW does not. Fix that.
Oversight in commit 4b74ebf726.
Author: Yugo Nagata
Reviewed-by: Jeff Davis
Discussion: https://postgr.es/m/20240805160502.d2a4975802a832b1e04afb80%40sraoss.co.jp
Backpatch-through: 17
An invalid toast index is skipped in reindex_relation(). These would be
remnants of a failed REINDEX CONCURRENTLY and they should never been
rebuilt as there can only be one valid toast index at a time.
REINDEX_REL_SUPPRESS_INDEX_USE, used by CLUSTER and VACUUM FULL, needs
to maintain a list of the indexes being processed. The list of indexes
is retrieved from the relation cache, and includes invalid indexes. The
code has missed that invalid toast indexes are ignored in
reindex_relation() as this leads to a hard failure in reindex_index(),
and they were left in the reindex pending list, making the list
inconsistent when rechecked. The incorrect memory access was happening
when scanning pg_class for the refresh of pg_database.datfrozenxid, when
doing a scan of pg_class.
This issue exists since REINDEX CONCURRENTLY exists, where invalid toast
indexes can exist, so backpatch all the way down.
Reported-by: Alexander Lakhin
Author: Tender Wang
Discussion: https://postgr.es/m/18630-9aed99c38830657d@postgresql.org
Backpatch-through: 12
There's no need to add another level of indentation to this status
message. pg_log() will put it in the right place.
Oversight in commit 347758b120.
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/ZunW7XHLd2uTts4f%40nathan
Backpatch-through: 17
Running vacuumdb with a non-superuser while another user has created a
temporary table would lead to a mid-flight permission failure,
interrupting the operation. vacuum_rel() skips temporary relations of
other backends, and it makes no sense for vacuumdb to know about these
relations, so let's switch it to ignore temporary relations entirely.
Adding a qual in the query based on relpersistence simplifies the
generation of its WHERE clause in vacuum_one_database(), per se the
removal of "has_where".
Author: VaibhaveS, Michael Paquier
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CAM_eQjwfAR=y3G1fGyS1U9FTmc+FyJm9amNfY2QCZBnDDbNPZg@mail.gmail.com
Backpatch-through: 12
The previous commit fixed some ways of losing an inplace update. It
remained possible to lose one when a backend working toward a
heap_update() copied a tuple into memory just before inplace update of
that tuple. In catalogs eligible for inplace update, use LOCKTAG_TUPLE
to govern admission to the steps of copying an old tuple, modifying it,
and issuing heap_update(). This includes MERGE commands. To avoid
changing most of the pg_class DDL, don't require LOCKTAG_TUPLE when
holding a relation lock sufficient to exclude inplace updaters.
Back-patch to v12 (all supported versions). In v13 and v12, "UPDATE
pg_class" or "UPDATE pg_database" can still lose an inplace update. The
v14+ UPDATE fix needs commit 86dc90056dfdbd9d1b891718d2e5614e3e432f35,
and it wasn't worth reimplementing that fix without such infrastructure.
Reviewed by Nitin Motiani and (in earlier versions) Heikki Linnakangas.
Discussion: https://postgr.es/m/20231027214946.79.nmisch@google.com
As previously-added tests demonstrated, heap_inplace_update() could
instead update an unrelated tuple of the same catalog. It could lose
the update. Losing relhasindex=t was a source of index corruption.
Inplace-updating commands like VACUUM will now wait for heap_update()
commands like GRANT TABLE and GRANT DATABASE. That isn't ideal, but a
long-running GRANT already hurts VACUUM progress more just by keeping an
XID running. The VACUUM will behave like a DELETE or UPDATE waiting for
the uncommitted change.
For implementation details, start at the systable_inplace_update_begin()
header comment and README.tuplock. Back-patch to v12 (all supported
versions). In back branches, retain a deprecated heap_inplace_update(),
for extensions.
Reported by Smolkin Grigory. Reviewed by Nitin Motiani, (in earlier
versions) Heikki Linnakangas, and (in earlier versions) Alexander
Lakhin.
Discussion: https://postgr.es/m/CAMp+ueZQz3yDk7qg42hk6-9gxniYbp-=bG2mgqecErqR5gGGOA@mail.gmail.com
The current use always releases this locktag. A planned use will
continue that intent. It will involve more areas of code, making unlock
omissions easier. Warn under debug_assertions, like we do for various
resource leaks. Back-patch to v12 (all supported versions), the plan
for the commit of the new use.
Reviewed by Heikki Linnakangas.
Discussion: https://postgr.es/m/20240512232923.aa.nmisch@google.com
Commit d1379ebf4 carelessly broke printACLColumn for pre-9.4 servers,
by using the cardinality() function which we introduced in 9.4.
We expect psql's describe-related commands to work back to 9.2, so
this is bad. Use the longstanding array_length() function instead.
Per report from Christoph Berg. Back-patch to v17.
Discussion: https://postgr.es/m/ZvLXYglRS6hMMhtr@msg.df7cb.de
Commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution, made
parallel index scans work with the new design for arrays via explicit
scheduling of primitive index scans. Under this scheme a parallel index
scan with array keys will perform the same number of index descents as
an equivalent serial index scan (barring corner cases where an
individual parallel worker discovers that it can advance the scan's
array keys without anybody needing to perform another descent of the
index to get to the relevant page on the leaf level).
Despite all this, the pgstats accounting wasn't updated; it continued to
increment the total number of index scans for the rel once per _bt_first
call, no matter the details. As a result, the number of (primitive)
index scans could be over-counted during parallel scans.
To fix, delay incrementing the count of index scans until after we've
established that another descent of the index (using either _bt_search
or _bt_endpoint) is required. That way pg_stat_user_tables.idx_scan
always advances in the same way, regardless of whether or not the scan
makes use of parallelism.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2-Wz=E7XrkvscBN0U6V81NK3Q-dQOmivvbEsjG-zwEfDdFpg@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkRqvaqR2CTNqTZP0z6FuL4-3ED6eQB0yx38XBNj1v-4Q@mail.gmail.com
Backpatch: 17-, where nbtree SAOP execution was enhanced.
FYI, during PDF builds, this link type generates a "Unresolved ID
reference found" warning because it is suppressed from the PDF output.
Backpatch-through: 12
Calling \bind repeatedly would cause the memory allocated for the list
of bind parameters to be leaked after each call, as the list is reset
when beginning a single call.
This issue is fixed by making the cleanup of the bind parameter list
more aggressive, refactoring it into a single routine called after
processing a query and before running an individual \bind.
HEAD required more surgery and has been fixed by 87eeadaea143. Issue
introduced by 5b66de3433e2.
Reported-by: Anthonin Bonnefoy
Discussion: https://postgr.es/m/2e5b89af-a351-ff0a-000c-037ac28314ab@gmail.com
Backpatch-through: 16
The previous documentation stated that num_timed reflects the number of
scheduled checkpoints performed. However, checkpoints may be skipped
if the server has been idle, and num_timed counts both skipped and completed
checkpoints. This commit clarifies the description to make it clear that
the counter includes both skipped and completed checkpoints.
Back-patch to v17 where pg_stat_checkpointer was added.
Author: Fujii Masao
Reviewed-by: Alexander Korotkov
Discussion: https://postgr.es/m/9ea77f40-818d-4841-9dee-158ac8f6e690@oss.nttdata.com
This commit adds query ID reports for two code paths when processing
extended query protocol messages:
- When receiving a bind message, setting it to the first Query retrieved
from a cached cache.
- When receiving an execute message, setting it to the first PlannedStmt
stored in a portal.
An advantage of this method is that this is able to cover all the types
of portals handled in the extended query protocol, particularly these
two when the report done in ExecutorStart() is not enough (neither is an
addition in ExecutorRun(), actually, for the second point):
- Multiple execute messages, with multiple ExecutorRun().
- Portal with execute/fetch messages, like a query with a RETURNING
clause and a fetch size that stores the tuples in a first execute
message going though ExecutorStart() and ExecuteRun(), followed by one
or more execute messages doing only fetches from the tuplestore created
in the first message. This corresponds to the case where
execute_is_fetch is set, for example.
Note that the query ID reporting done in ExecutorStart() is still
necessary, as an EXECUTE requires it. Query ID reporting is optimistic
and more calls to pgstat_report_query_id() don't matter as the first
report takes priority except if the report is forced. The comment in
ExecutorStart() is adjusted to reflect better the reality with the
extended query protocol.
The test added in pg_stat_statements is a courtesy of Robert Haas. This
uses psql's \bind metacommand, hence this part is backpatched down to
v16.
Reported-by: Kaido Vaikla, Erik Wienhold
Author: Sami Imseih
Reviewed-by: Jian He, Andrei Lepikhov, Michael Paquier
Discussion: https://postgr.es/m/CA+427g8DiW3aZ6pOpVgkPbqK97ouBdf18VLiHFesea2jUk3XoQ@mail.gmail.com
Discussion: https://postgr.es/m/CA+TgmoZxtnf_jZ=VqBSyaU8hfUkkwoJCJ6ufy4LGpXaunKrjrg@mail.gmail.com
Discussion: https://postgr.es/m/1391613709.939460.1684777418070@office.mailbox.org
Backpatch-through: 14
Commits 041b9680 and 6377e12a changed the interface of
scan_analyze_next_block() to take a ReadStream instead of a BlockNumber
and a BufferAccessStrategy, and to return a value to indicate when the
stream has run out of blocks.
This caused integration problems for at least one known extension that
uses specially encoded BlockNumber values that map to different
underlying storage, because acquire_sample_rows() sets up the stream so
that read_stream_next_buffer() reads blocks from the main fork of the
relation's SMgrRelation.
Provide read_stream_next_block(), as a way for such an extension to
access the stream of raw BlockNumbers directly and forward them to its
own ReadBuffer() calls after decoding, as it could in earlier releases.
The new function returns the BlockNumber and BufferAccessStrategy that
were previously passed directly to scan_analyze_next_block().
Alternatively, an extension could wrap the stream of BlockNumbers in
another ReadStream with a callback that performs any decoding required
to arrive at real storage manager BlockNumber values, so that it could
benefit from the I/O combining and concurrency provided by
read_stream.c.
Another class of table access method that does nothing in
scan_analyze_next_block() because it is not block-oriented could use
this function to control the number of block sampling loops. It could
match the previous behavior with "return read_stream_next_block(stream,
&bas) != InvalidBlockNumber".
Ongoing work is expected to provide better ANALYZE support for table
access methods that don't behave like heapam with respect to storage
blocks, but that will be for future releases.
Back-patch to 17.
Reported-by: Mats Kindahl <mats@timescale.com>
Reviewed-by: Mats Kindahl <mats@timescale.com>
Discussion: https://postgr.es/m/CA%2B14425%2BCcm07ocG97Fp%2BFrD9xUXqmBKFvecp0p%2BgV2YYR258Q%40mail.gmail.com
Since we introduced unlogged sequences in v15, identity sequences
have defaulted to having the same persistence as their owning table.
However, it is possible to change that with ALTER SEQUENCE, and
pg_dump tries to preserve the logged-ness of sequences when it doesn't
match (as indeed it wouldn't for an unlogged table from before v15).
The fly in the ointment is that ALTER SEQUENCE SET [UN]LOGGED fails
in binary-upgrade mode, because it needs to assign a new relfilenode
which we cannot permit in that mode. Thus, trying to pg_upgrade a
database containing a mismatching identity sequence failed.
To fix, add syntax to ADD/ALTER COLUMN GENERATED AS IDENTITY to allow
the sequence's persistence to be set correctly at creation, and use
that instead of ALTER SEQUENCE SET [UN]LOGGED in pg_dump. (I tried to
make SET [UN]LOGGED work without any pg_dump modifications, but that
seems too fragile to be a desirable answer. This way should be
markedly faster anyhow.)
In passing, document the previously-undocumented SEQUENCE NAME option
that pg_dump also relies on for identity sequences; I see no value
in trying to pretend it doesn't exist.
Per bug #18618 from Anthony Hsu.
Back-patch to v15 where we invented this stuff.
Discussion: https://postgr.es/m/18618-d4eb26d669ed110a@postgresql.org
Commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution, made
parallel index scans work with the new design for arrays via explicit
scheduling of primitive index scans. A backend that successfully
scheduled the scan's next primitive index scan saved its backend local
array keys in shared memory. Any backend could pick up the scheduled
primitive scan within _bt_first. This scheme decouples scheduling a
primitive scan from starting the scan (by performing another descent of
the index via a _bt_search call from _bt_first) to make things robust.
The scheme had a deadlock hazard, at least when the leader process
participated in the scan. _bt_parallel_seize had a code path that made
backends that were not in an immediate position to start a scheduled
primitive index scan wait for some other backend to do so instead.
Under the right circumstances, the leader process could wait here
forever: the leader would wait for any other backend to start the
primitive scan, while every worker was busy waiting on the leader to
consume tuples from the scan's tuple queue.
To fix, don't wait for a scheduled primitive index scan to be started by
some other eligible backend from within _bt_parallel_seize (when the
calling backend isn't in a position to do so itself). Return false
instead, while recording that the scan has a scheduled primitive index
scan in backend local state. This leaves the backend in the same state
as the existing case where a backend schedules (or tries to schedule)
another primitive index scan from within _bt_advance_array_keys, before
calling _bt_parallel_seize. _bt_parallel_seize already handles that
case by returning false without waiting, and without unsetting the
backend local state. Leaving the backend in this state enables it to
start a previously scheduled primitive index scan once it gets back to
_bt_first.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Matthias van de Meent, with tweaks by me.
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reported-By: Tomas Vondra <tomas@vondra.me>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzmMGaPa32u9x_FvEbPTUkP5e95i=QxR8054nvCRydP-sw@mail.gmail.com
Backpatch: 17-, where nbtree SAOP execution was enhanced.
In existing releases of libxml2, xmlXPathCompile can be driven
to stack overflow because it fails to protect itself against
too-deeply-nested input. While there is an upstream fix as of
yesterday, it will take years for that to propagate into all
shipping versions. In the meantime, we can protect our own
usages basically for free by calling xmlXPathCtxtCompile instead.
(The actual bug is that libxml2 keeps its nesting counter in the
xmlXPathContext, and its parsing code was willing to just skip
counting nesting levels if it didn't have a context. So if we supply
a context, all is well. It seems odd actually that it works at all
to not supply a context, because this means that XPath parsing does
not have access to XML namespace info. Apparently libxml2 never
checks namespaces until runtime? Anyway, this seems like good
future-proofing even if its only immediate effect is to dodge a bug.)
Sadly, this hack only offers protection with libxml2 2.9.11 and newer.
Before that there are multiple similar problems, so if you are
processing untrusted XML it behooves you to get a newer version.
But we have some pretty old libxml2 in the buildfarm, so it seems
impractical to add a regression test to verify this fix.
Per bug #18617 from Jingzhou Fu. Back-patch to all supported
versions.
Discussion: https://postgr.es/m/18617-1cee4d2ed1f4e7ae@postgresql.org
Discussion: https://gitlab.gnome.org/GNOME/libxml2/-/issues/799
Historically we've used timezone "PST8PDT", but the recent release
2024b of tzdb changes the definition of that zone in a way that
breaks many test cases concerned with dates before 1970. Although
we've not yet adopted 2024b into our own tree, this is already
problematic for people using --with-system-tzdata if their platform
has already adopted 2024b. To work with both older and newer
versions of tzdb, switch to using "America/Los_Angeles", accepting
the ensuing changes in regression test results.
Back-patch to all supported branches.
Per report and patch from Wolfgang Walther.
Discussion: https://postgr.es/m/0a997455-5aba-4cf2-a354-d26d8bcbfae6@technowledgy.de
The current method of detecting perl build flags breaks if the path to
perl contains a space. This change makes two improvements. First,
instead of getting a list of ldflags and ccdlflags and then trying to
filter those out of the reported ldopts, we tell perl to suppress
reporting those in the first instance. Second, it tells perl to parse
those and output them, one per line. Thus any space on the option in a
file name, for example, is preserved.
Issue reported off-list by Muralikrishna Bandaru
Discussion: https://postgr.es/01117f88-f465-bf6c-9362-083bd72ca305@dunslane.net
Backpatch to release 16.
Latest versions of Strawberry Perl define USE_THREAD_SAFE_LOCALE, and we
therefore get a handshake error when building against such instances.
The solution is to perform a test to see if USE_THREAD_SAFE_LOCALE is
defined and only define NO_THREAD_SAFE_LOCALE if it isn't.
Backpatch the meson.build fix back to release 16 and apply the same
logic to Mkvcbuild.pm in releases 12 through 16.
Original report of the issue from Muralikrishna Bandaru.
