We are capable of optimizing MIN() and MAX() aggregates on indexed
columns into subqueries that exploit the index, rather than the normal
thing of scanning the whole table. When we do this, we replace the
Aggref node(s) with Params referencing subquery outputs. Such Params
really ought to be included in the per-plan-node extParam/allParam
sets computed by SS_finalize_plan. However, we've never done so
up to now because of an ancient implementation choice to perform
that substitution during set_plan_references, which runs after
SS_finalize_plan, so that SS_finalize_plan never sees these Params.
The cleanest fix would be to perform a separate tree walk to do
these substitutions before SS_finalize_plan runs. That seems
unattractive, first because a whole-tree mutation pass is expensive,
and second because we lack infrastructure for visiting expression
subtrees in a Plan tree, so that we'd need a new function knowing
as much as SS_finalize_plan knows about that. I also considered
swapping the order of SS_finalize_plan and set_plan_references,
but that fell foul of various assumptions that seem tricky to fix.
So the approach adopted here is to teach SS_finalize_plan itself
to check for such Aggrefs. I refactored things a bit in setrefs.c
to avoid having three copies of the code that does that.
Back-patch of v17 commits d0d44049d and 779ac2c74. When d0d44049d
went in, there was no evidence that it was fixing a reachable bug,
so I refrained from back-patching. Now we have such evidence.
Per bug #18465 from Hal Takahara. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18465-2fae927718976b22@postgresql.org
Discussion: https://postgr.es/m/2391880.1689025003@sss.pgh.pa.us
Specifically, it terminates a background worker even if the caller
couldn't terminate the background worker with pg_terminate_backend().
Commit 3a9b18b309 neglected to update
this. Back-patch to v13, which introduced DROP DATABASE FORCE.
Reviewed by Amit Kapila. Reported by Kirill Reshke.
Discussion: https://postgr.es/m/20240429212756.60.nmisch@google.com
9a974cbcba moved the query in binary_upgrade_set_pg_class_oids to the
outer level, but left the PQclear and query buffer destruction in the
is_index conditional. 353708e1fb fixed the leak of the query buffer
but left the PGresult leak. This moves clearing the result to the outer
level ensuring that it will be called.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/374550C1-F4ED-4D9D-9498-0FD029CCF674@yesql.se
Backpatch-through: v15
Underscores were added to numeric literals in faff8f8e47. This change
also affected the positional parameters (e.g., $1) rule, which uses
the same production for its digits. But this did not actually work,
because the digits for parameters are processed using atol(), which
does not handle underscores and ignores whatever it cannot parse.
The underscores notation is probably not useful for positional
parameters, so for simplicity revert that rule to its old form that
only accepts digits 0-9.
Author: Erik Wienhold <ewie@ewie.name>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/5d216d1c-91f6-4cbe-95e2-b4cbd930520c%40ewie.name
Most of the infrastructure for procedure arguments was already
okay with polymorphic output arguments, but it turns out that
CallStmtResultDesc() was a few bricks shy of a load here. It thought
all it needed to do was call build_function_result_tupdesc_t, but
that function specifically disclaims responsibility for resolving
polymorphic arguments. Failing to handle that doesn't seem to be
a problem for CALL in plpgsql, but CALL from plain SQL would get
errors like "cannot display a value of type anyelement", or even
crash outright.
In v14 and later we can simply examine the exposed types of the
CallStmt.outargs nodes to get the right type OIDs. But it's a lot
more complicated to fix in v12/v13, because those versions don't
have CallStmt.outargs, nor do they do expand_function_arguments
until ExecuteCallStmt runs. We have to duplicatively run
expand_function_arguments, and then re-determine which elements
of the args list are output arguments.
Per bug #18463 from Drew Kimball. Back-patch to all supported
versions, since it's busted in all of them.
Discussion: https://postgr.es/m/18463-f8cd77e12564d8a2@postgresql.org
Presently, when this function is called for an unlogged sequence on
a standby server, it will error out with a message like
ERROR: could not open file "base/5/16388": No such file or directory
Since the pg_sequences system view uses pg_sequence_last_value(),
it can error similarly. To fix, modify the function to return NULL
for unlogged sequences on standby servers. Since this bug is
present on all versions since v15, this approach is preferable to
making the ERROR nicer because we need to repair the pg_sequences
view without modifying its definition on released versions. For
consistency, this commit also modifies the function to return NULL
for other sessions' temporary sequences. The pg_sequences view
already appropriately filters out such sequences, so there's no bug
there, but we might as well offer some defense in case someone
invokes this function directly.
Unlogged sequences were first introduced in v15, but temporary
sequences are much older, so while the fix for unlogged sequences
is only back-patched to v15, the temporary sequence portion is
back-patched to all supported versions.
We could also remove the privilege check in the pg_sequences view
definition in v18 if we modify this function to return NULL for
sequences for which the current user lacks privileges, but that is
left as a future exercise for when v18 development begins.
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20240501005730.GA594666%40nathanxps13
Backpatch-through: 12
If we recursed to a new call of the same function, with a different
coldeflist (AS clause), it would fail because the inner call would
overwrite the outer call's idea of what to return. This is vaguely
like 1d2fe56e4 and c5bec5426, but it's not due to any API decisions:
it's just that we computed the actual output rowtype at the start of
the call, and saved it in the per-procedure data structure. We can
fix it at basically zero cost by doing the computation at the end
of each call instead of the start.
It's not clear that there's any real-world use-case for such a
function, but given that it doesn't cost anything to fix,
it'd be silly not to.
Per report from Andreas Karlsson. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/1651a46d-3c15-4028-a8c1-d74937b54e19@proxel.se
json_lex_string() relies on pg_encoding_mblen_bounded() to point to the
end of a JSON string when generating an error message, and the input it
uses is not guaranteed to be null-terminated.
It was possible to walk off the end of the input buffer by a few bytes
when the last bytes consist of an incomplete multi-byte sequence, as
token_terminator would point to a location defined by
pg_encoding_mblen_bounded() rather than the end of the input. This
commit switches token_terminator so as the error uses data up to the
end of the JSON input.
More work should be done so as this code could rely on an equivalent of
report_invalid_encoding() so as incorrect byte sequences can show in
error messages in a readable form. This requires work for at least two
cases in the JSON parsing API: an incomplete token and an invalid escape
sequence. A more complete solution may be too invasive for a backpatch,
so this is left as a future improvement, taking care of the overread
first.
A test is added on HEAD as test_json_parser makes this issue
straight-forward to check.
Note that pg_encoding_mblen_bounded() no longer has any callers. This
will be removed on HEAD with a separate commit, as this is proving to
encourage unsafe coding.
Author: Jacob Champion
Discussion: https://postgr.es/m/CAOYmi+ncM7pwLS3AnKCSmoqqtpjvA8wmCdoBtKA3ZrB2hZG6zA@mail.gmail.com
Backpatch-through: 13
If -l was specified together with selective-restore options such as -n
or -N, dependent TOC entries such as comments would be omitted from
the listing, even when an actual restore would have selected them.
This happened because PrintTOCSummary neglected to update the te->reqs
marking of the entry they depended on.
Per report from Justin Pryzby. This has been wrong since 0d4e6ed30
taught _tocEntryRequired to sometimes look at the "reqs" marking of
other TOC entries, so back-patch to all supported branches.
Discussion: https://postgr.es/m/ZjoeirG7yxODdC4P@pryzbyj2023
If a plpython-language trigger caused another one to be invoked,
the "TD" dictionary created for the inner one would overwrite the
outer one's "TD" dictionary. This is more or less the same problem
that 1d2fe56e4 fixed for ordinary functions in plpython, so fix it
the same way, by saving and restoring "TD" during a recursive
invocation.
This fix makes an ABI-incompatible change in struct PLySavedArgs.
I'm not too worried about that because it seems highly unlikely that
any extension is messing with those structs. We could imagine doing
something weird to preserve nominal ABI compatibility in the back
branches, like keeping the saved TD object in an extra element of
namedargs[]. However, that would only be very nominal compatibility:
if anything *is* touching PLySavedArgs, it would likely do the wrong
thing due to not knowing about the additional value. So I judge it
not worth the ugliness to do something different there.
(I also changed struct PLyProcedure, but its added field fits
into formerly-padding space, so that should be safe.)
Per bug #18456 from Jacques Combrink. This bug is very ancient,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/3008982.1714853799@sss.pgh.pa.us
The catalog view pg_stats_ext fails to consider privileges for
expression statistics. The catalog view pg_stats_ext_exprs fails
to consider privileges and row-level security policies. To fix,
restrict the data in these views to table owners or roles that
inherit privileges of the table owner. It may be possible to apply
less restrictive privilege checks in some cases, but that is left
as a future exercise. Furthermore, for pg_stats_ext_exprs, do not
return data for tables with row-level security enabled, as is
already done for pg_stats_ext.
On the back-branches, a fix-CVE-2024-4317.sql script is provided
that will install into the "share" directory. This file can be
used to apply the fix to existing clusters.
Bumps catversion on 'master' branch only.
Reported-by: Lukas Fittl
Reviewed-by: Noah Misch, Tomas Vondra, Tom Lane
Security: CVE-2024-4317
Backpatch-through: 14
The documentation said that you need to pick a suitable LC_COLLATE
setting in addition to setting the DETERMINISTIC flag. This would
have been correct if the libc provider supported nondeterministic
collations, but since it doesn't, you actually need to set the LOCALE
option.
Reviewed-by: Kashif Zeeshan <kashi.zeeshan@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/a71023c2-0ae0-45ad-9688-cf3b93d0d65b%40eisentraut.org
When testing pg_upgrade against an old server, ignore failures on the
check to upgrade invalid databases. This is necessary because old
servers don't know to raise the appropriate error of the database being
invalid.
This change causes no reduction in coverage, because such old versions
don't know to mark databases invalid when a drop is interrupted; but
testing against such old servers is useful in some circumstances.
Backpatch to 16, where it cherry-picks with minimal conflicts.
On 16, perltidy 20230309 chooses to change an unrelated line. I let it
do that because that's the version we document as preferred for that
branch, even though it would make other changes to many other files in
the tree.
Discussion: https://postgr.es/m/202404181539.lh42llaesnv3@alvherre.pgsql
94985c210 added code to detect when WindowFuncs were monotonic and
allowed additional quals to be "pushed down" into the subquery to be
used as WindowClause runConditions in order to short-circuit execution
in nodeWindowAgg.c.
The Node representation of runConditions wasn't well selected and
because we do qual pushdown before planning the subquery, the planning
of the subquery could perform subquery pull-up of nested subqueries.
For WindowFuncs with args, the arguments could be changed after pushing
the qual down to the subquery.
This was made more difficult by the fact that the code duplicated the
WindowFunc inside an OpExpr to include in the WindowClauses runCondition
field. This could result in duplication of subqueries and a pull-up of
such a subquery could result in another initplan parameter being issued
for the 2nd version of the subplan. This could result in errors such as:
ERROR: WindowFunc not found in subplan target lists
Here in the backbranches, we don't have the flexibility to improve the
Node representation to resolve this, so instead we just disable the
runCondition optimization for ntile() unless the argument is a Const,
(v16 only) and likewise for count(expr) (both v15 and v16). count(*) is
unaffected. All other window functions which support this optimization
all take zero arguments and therefore are unaffected.
Bug: #18170
Reported-by: Zuming Jiang
Discussion: https://postgr.es/m/18170-f1d17bf9a0d58b24@postgresql.org
Backpatch-through 15 (master will be fixed independently)
A parallel worker's buffer usage is accumulated to its pgBufferUsage
and then is accumulated into the leader's one at the end of the
parallel vacuum. However, since the leader process used to use
dedicated VacuumPage{Hit, Miss, Dirty} globals for the buffer usage
reporting, the worker's buffer usage was not included, leading to an
incorrect buffer usage report.
To fix the problem, this commit makes vacuum use pgBufferUsage
instruments for buffer usage reporting instead of VacuumPage{Hit,
Miss, Dirty} globals. These global variables are still used by ANALYZE
command and autoanalyze.
This also fixes the buffer usage report of vacuuming on temporary
tables, since the buffers dirtied by MarkLocalBufferDirty() were not
tracked by the VacuumPageDirty variable.
Parallel vacuum was introduced in 13, but the buffer usage reporting
for VACUUM command with the VERBOSE option was implemented in
15. So backpatch to 15.
Reported-by: Anthonin Bonnefoy
Author: Anthonin Bonnefoy
Reviewed-by: Alena Rybakina, Masahiko Sawada
Discussion: https://postgr.es/m/CAO6_XqrQk+QZQcYs_C6nk0cMfHuUWk85vT9CrcA1NffFbAVE2A@mail.gmail.com
Backpatch-through: 15
As an optimization, we store "name" columns as cstrings in btree
indexes.
Here we modify it so that Index Only Scans convert these cstrings back
to names with NAMEDATALEN bytes rather than storing the cstring in the
tuple slot, as was happening previously.
Bug: #17855
Reported-by: Alexander Lakhin
Reviewed-by: Alexander Lakhin, Tom Lane
Discussion: https://postgr.es/m/17855-5f523e0f9769a566@postgresql.org
Backpatch-through: 12, all supported versions
vac_update_datfrozenxid() did multiple loads of relfrozenxid and
relminmxid from buffer memory, and it assumed each would get the same
value. Not so if a concurrent vac_update_relstats() did an inplace
update. Commit 2d2e40e3be fixed the same
kind of bug in vac_truncate_clog(). Today's bug could cause the
rel-level field and XIDs in the rel's rows to precede the db-level
field. A cluster having such values should VACUUM affected tables.
Back-patch to v12 (all supported versions).
Discussion: https://postgr.es/m/20240423003956.e7.nmisch@google.com
ALTER COLUMN TYPE wasn't expecting to find any pg_proc objects
depending on the column whose type is to be altered. That indeed
wasn't possible when this code was written, but it is possible
since we introduced new-style SQL function bodies.
It's about as difficult to fix this case as it is to fix dependent
views, and we've been punting on those for years, so I don't feel
too awful about punting for functions too. (I sure wouldn't risk
back-patching such code.) So just throw a more user-facing error.
Also, adjust some of the existing comments to reflect that these
are all pretty much the same issue.
(This patch also fixes it so we will tolerate finding such a
dependency during ALTER COLUMN SET EXPRESSION; in that, we need
not do anything to the function, so no error is wanted. That
problem is new in HEAD.)
Per bug #18449 from Alexander Lakhin. Back-patch to v14 where
we added new-style SQL functions.
Discussion: https://postgr.es/m/18449-f8248467aaa294d5@postgresql.org
In commit 25cd2d640 I (tgl) opined that "The additions of the months
and microseconds fields could also overflow, of course. However,
I believe we need no additional checks there; the existing range
checks should catch such cases". This is demonstrably wrong however
for the microseconds field, and given that discovery it seems prudent
to be paranoid about the months addition as well.
Report and patch by Joseph Koshakow. As before, back-patch to all
supported branches. (However, the test case doesn't work before
v15 because we didn't allow wider-than-int32 numbers in interval
literals. A variant test could probably be built that fits within
that restriction, but it didn't seem worth the trouble.)
Discussion: https://postgr.es/m/CAAvxfHf77sRHKoEzUw9_cMYSpbpNS2C+J_+8Dq4+0oi8iKopeA@mail.gmail.com
In the wake of commits dac048f71 and ecaf7c5df, `make headerscheck`
no longer generated all headers that are included by other headers,
causing headerscheck/cpluspluscheck to fail. To fix, backpatch enough
makefile rules from 721856ff2 to generate all required headers.
Reported by Marina Polyakova
Backpatch to version 16 only, as the issue is not present on master
Discussion: https://postgr.es/m/231ea1127719b2b3d6d1c05f75808981%40postgrespro.ru
In e6927270cd I added a 'touch meson.build' to configure.ac, to ensure
conflicts between in-tree configure based builds and meson builds are
automatically detected. Unfortunately I omitted spaces around the condition
restricting this to in-tree builds, leading to touch meson.build to also be
executed in vpath builds. While the only consequence of this buglet is an
unnecessary empty file in build directories, it seems worth backpatching.
Reported-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/20240417230002.mb2gv3hyetyn67gk@awork3.anarazel.de
Backpatch: 16-, where the meson based build was added
We missed performing table sync if the invalidation happened while the
non-ready tables list was being prepared. This occurs because the sync
state was set to valid at the end of non-ready table list preparation
irrespective of the invalidations processed while the list is being
prepared.
Fix it by changing the boolean variable to a tri-state enum and by setting
table state to valid only if no invalidations have occurred while the list
is being prepared.
Reprted-by: Alexander Lakhin
Diagnosed-by: Alexander Lakhin
Author: Vignesh C
Reviewed-by: Hou Zhijie, Alexander Lakhin, Ajin Cherian, Amit Kapila
Backpatch-through: 15
Discussion: https://postgr.es/m/711a6afe-edb7-1211-cc27-1bef8239eec7@gmail.com
The paragraph describing the JavaScript string literals allowed in
jsonpath expressions unnecessarily mentions JSON by erroneously
listing \v as allowed by JSON and mentioning the \xNN and \u{N...}
backslash escapes as deviations from JSON when in fact both are
accepted by ECMAScript/JavaScript. Fix this by only referring to
JavaScript.
Author: Erik Wienhold <ewie@ewie.name>
Discussion: https://www.postgresql.org/message-id/flat/1EB17DF9-2636-484B-9DD0-3CAB19C4F5C4@justatheory.com
When specifying the createdb strategy, the documentation suggests valid
options are FILE_COPY and WAL_LOG, but the code does case-sensitive
comparison and accepts only "file_copy" and "wal_log" as valid.
Fixed by doing a case-insensitive comparison using pg_strcasecmp(), same
as for other string parameters nearby.
While at it, apply fmtId() to a nearby "locale_provider". This already
did the comparison in case-insensitive way, but the value would not be
double-quoted, confusing the parser and the error message.
Backpatch to 15, where the strategy was introduced.
Backpatch-through: 15
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/90c6913a-1dd2-42b4-8365-ce3b09c39b17@enterprisedb.com
This should have the same results for all practical purposes.
The advantage of selecting 'GMT' is that it's guaranteed to work
even when the remote system's timezone database is missing
entries, because pg_tzset() hard-wires handling of that,
at least in 9.2 and later.
(It seems like it would be a good idea to similarly hard-wire
correct handling of 'UTC', but that'll be a little more invasive
than I want to consider back-patching. Leave that for another
day when we're not in feature freeze.)
Per trouble report from Adnan Dautovic. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/465248.1712211585@sss.pgh.pa.us
The documents were clear that queryid should not be assumed to be stable
between major versions but said nothing about minor versions and left
the reader to guess if that was implied by the mention of the
instability of queryid between major versions.
Here we give minor versions an explicit mention to indicate queryid can
generally be assumed stable between minor versions.
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAApHDvpYGE6h0cD9UO-eHySPynPj1L3J%3DHxT%2BA7Ud8_Yo6AuzA%40mail.gmail.com
Backpatch-through: 12
These operators were removed by 2f70fdb064 in the v14 cycle but they were
accidentally left in the table of build-in operator classes. Backpatch down
to v14 where the operators where removed.
Author: Aleksander Alekseev <aleksander@timescale.com>
Reported-by: Colin Caine <cmcaine@gmail.com>
Discussion: https://postgr.es/m/CADwQTQbbr2UQ_fpbyc+8ay=RwEYgYk=TZxH3+RHDqAQfoG+EWA@mail.gmail.com
Backpatch-through: v14
While back-patching commit 6f0cef935, I forgot that the MSVC
build scripts would also need adjustment in the back branches.
This is a blind attempt at a fix, but it's basically copying
nearby code so I think it will work.
Per buildfarm (via Andrew Dunstan)
Discussion: https://postgr.es/m/4cc4dc47-ca2b-4129-8784-db69b5f82777@dunslane.net
The code associated with EXEC SQL DEFINE was unreadable and full of
bugs, notably:
* It'd attempt to free a non-malloced string if the ecpg program
tries to redefine a macro that was defined on the command line.
* Possible memory stomp if user writes "-D=foo".
* Undef'ing or redefining a macro defined on the command line would
change the state visible to the next file, when multiple files are
specified on the command line. (While possibly that could have been
an intentional choice, the code clearly intends to revert to the
original macro state; it's just failing to consider this interaction.)
* Missing "break" in defining a new macro meant that redefinition
of an existing name would cause an extra entry to be added to the
definition list. While not immediately harmful, a subsequent undef
would result in the prior entry becoming visible again.
* The interactions with input buffering are subtle and were entirely
undocumented.
It's not that surprising that we hadn't noticed these bugs,
because there was no test coverage at all of either the -D
command line switch or multiple input files. This patch adds
such coverage (in a rather hacky way I guess).
In addition to the code bugs, the user documentation was confused
about whether the -D switch defines a C macro or an ecpg one, and
it failed to mention that you can write "-Dsymbol=value".
These problems are old, so back-patch to all supported branches.
Discussion: https://postgr.es/m/998011.1713217712@sss.pgh.pa.us
When building a join clause derived from an EquivalenceClass, if the
clause is to be used with an appendrel child relation then make sure
its clause_relids include the relids of that child relation.
Normally this would be true already because the EquivalenceMember
would be a Var of that relation. However, if the appendrel represents
a flattened UNION ALL construct then some child EquivalenceMembers
could be constants with no relids. The resulting under-marked clause
is problematic because it could mislead join_clause_is_movable_into
about where the clause should be evaluated. We do not have an example
showing incorrect plan generation, but there are existing cases in
the regression tests that will fail the Asserts this patch adds to
get_baserel_parampathinfo. A similarly wrong conclusion about a
clause being considered by get_joinrel_parampathinfo would lead to
wrong placement of the clause. (This also squares with the way
that clause_relids is calculated for non-equijoin clauses in
adjust_appendrel_attrs.)
The other reason for wanting these new Asserts is that the previous
blithe assumption that the results of generate_join_implied_equalities
"necessarily satisfy join_clause_is_movable_into" turns out to be
wrong pre-v16. If it's still wrong it'd be good to find out.
Per bug #18429 from Benoît Ryder. The bug as filed was fixed by
commit 2489d76c4, but these changes correlate with the fix we
will need to apply in pre-v16 branches.
Discussion: https://postgr.es/m/18429-8982d4a348cc86c6@postgresql.org
Some functions are used in the tree and are currently marked as
deprecated by upstream. This commit refreshes the code to use the
recommended functions, leading to the following changes:
- xmlSubstituteEntitiesDefault() is gone, and needs to be replaced with
XML_PARSE_NOENT for the paths doing the parsing.
- xmlParseMemory() -> xmlReadMemory().
These functions, as well as more functions setting global states, have
been officially marked as deprecated by upstream in August 2022. Their
replacements exist since the 2001-ish area, as far as I have checked,
so that should be safe.
This has been originally applied as 65c5864d7f without a backpatch,
and this has come up as well when working on 400928b83. Per request
from Tom Lane, for new buildfarm member indri that is able to see
deprecation warnings with xmlSubstituteEntitiesDefault() in 16 and older
stable branches.
Author: Dmitry Koval
Discussion: https://postgr.es/m/18274-98d16bc03520665f@postgresql.org
Discussion: https://postgr.es/m/1012981.1713222862@sss.pgh.pa.us
Bakpatch-through: 12
Commit 2ed8f9a01 intended to institute a policy that if a
RangeTblFunction has a coldeflist, then the function return type is
certainly RECORD, and we should use the coldeflist as the source of
truth about what the columns of the record type are. When the
original function has been folded to a constant, inspection of the
constant might give a different answer. This situation will lead to
a tuple-type-mismatch error at execution, but up until that point we
need to consistently believe the coldeflist, or we'll have problems
from different bits of code reaching different conclusions.
expandRTE didn't get that memo though, and would try to produce a
tupdesc based on the constant in this situation, leading to an
assertion failure. (Desultory testing suggests that non-assert
builds often manage to give the expected error, although I also
saw a "cache lookup failed for type 0" error, and it seems at
least possible that a crash could happen.)
Some other callers of get_expr_result_type and get_expr_result_tupdesc
were also being incautious about this. While none of them seem to
have actual bugs, they're working harder than necessary in this case,
besides which it seems safest to have an explicit policy of not using
those functions on an RTE with a coldeflist. Adjust the code
accordingly, and add commentary to funcapi.c about this policy.
Also fix an obsolete comment that claimed "get_expr_result_type()
doesn't know how to extract type info from a RECORD constant".
That hasn't been true since commit d57534740.
Per bug #18422 from Alexander Lakhin.
As with the previous commit, back-patch to all supported branches.
Discussion: https://postgr.es/m/18422-89ca86c8eac5246d@postgresql.org
Commit 6bcda4a721 replaced PG_DETOAST_DATUM with PG_DETOAST_DATUM_PACKED
in two BRIN output functions, for minmax-multi and bloom opclasses. But
this is incorrect - the code is accessing the data through structs that
already include a 4B header, so the detoast needs to match that. But the
PACKED macro may keep the 1B header, which means the struct fields will
point to incorrect data.
Backpatch-through: 16
Discussion: https://postgr.es/m/1df00a66-db5a-4e66-809a-99b386a06d86%40enterprisedb.com
Properly update the number of bits set in the bitmap after merging the
filters in brin_bloom_union.
This is mostly harmless, as the counter is used only in the output
function, which means pageinspect may show incorrect information about
the BRIN summary. The counter does not affect correctness.
Discovered while adding a regression test comparing indexes built with
and without parallelism. The parallel index builds exercise the union
procedure when merging results from workers, which is otherwise very
hard to do in a test. Which is why this went unnoticed until now.
Backpatch through 14, where the BRIN bloom opclasses were introduced.
Backpatch-through: 14
Discussion: https://postgr.es/m/1df00a66-db5a-4e66-809a-99b386a06d86%40enterprisedb.com
GetPageWithFreeSpace() callers assume the returned block exists in the
main fork, failing with "could not read block" errors if that doesn't
hold. Make that assumption reliable now. It hadn't been guaranteed,
due to the weak WAL and data ordering of participating components. Most
operations on the fsm fork are not WAL-logged. Relation extension is
not WAL-logged. Hence, an fsm-fork block on disk can reference a
main-fork block that no WAL record has initialized. That could happen
after an OS crash, a replica promote, or a PITR restore. wal_log_hints
makes the trouble easier to hit; a replica promote or PITR ending just
after a relevant fsm-fork FPI_FOR_HINT may yield this broken state. The
v16 RelationAddBlocks() mechanism also makes the trouble easier to hit,
since it bulk-extends even without extension lock waiters. Commit
917dc7d239 stopped trouble around
truncation, but vectors involving PageIsNew() pages remained.
This implementation adds a RelationGetNumberOfBlocks() call when the
cached relation size doesn't confirm a block exists. We've been unable
to identify a benchmark that slows materially, but this may show up as
additional time in lseek(). An alternative without that overhead would
be a new ReadBufferMode such that ReadBufferExtended() returns NULL
after a 0-byte read, with all other errors handled normally. However,
each GetFreeIndexPage() caller would then need code for the return-NULL
case. Back-patch to v14, due to earlier versions not caching relation
size and the absence of a pre-v16 problem report.
Ronan Dunklau. Reported by Ronan Dunklau.
Discussion: https://postgr.es/m/1878547.tdWV9SEqCh%40aivenlaptop