Instead of emitting a separate XLOG_HEAP2_VISIBLE WAL record for each
page that becomes all-visible in vacuum's third phase, specify the VM
changes in the already emitted XLOG_HEAP2_PRUNE_VACUUM_CLEANUP record.
Visibility checks are now performed before marking dead items unused.
This is safe because the heap page is held under exclusive lock for the
entire operation.
This reduces the number of WAL records generated by VACUUM phase III by
up to 50%.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZMw6Npd_qm2KM%2BFwQ3cMOMx1Dh3VMhp8-V7SOLxdK9-g%40mail.gmail.com
log_error() would probably fail completely if used, and would
certainly print garbage for anything that needed to be interpolated
into the message, because it was failing to use the correct printing
subroutine for a va_list argument.
This bug likely went undetected because the error cases this code
is used for are rarely exercised - they only occur when Windows
security API calls fail catastrophically (out of memory, security
subsystem corruption, etc).
The FRONTEND variant can be fixed just by calling vfprintf()
instead of fprintf(). However, there was no va_list variant
of write_stderr(), so create one by refactoring that function.
Following the usual naming convention for such things, call
it vwrite_stderr().
Author: Bryan Green <dbryan.green@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAF+pBj8goe4fRmZ0V3Cs6eyWzYLvK+HvFLYEYWG=TzaM+tWPnw@mail.gmail.com
Backpatch-through: 13
Remove a variable that is no longer in use following commit 9a2e2a28.
It's not immediately clear why there were no compiler warnings about
this oversight.
Author: Peter Geoghegan <pg@bowt.ie>
Backpatch-through: 18
Commit 71f4c8c6f7 (which implemented DETACH CONCURRENTLY) added code
to create a separate table constraint when a table is detached
concurrently, identical to the partition constraint, on the theory that
such a constraint was needed in case the optimizer had constructed any
query plans that depended on the constraint being there. However, that
theory was apparently bogus because any such plans would be invalidated.
For hash partitioning, those constraints are problematic, because their
expressions reference the OID of the parent partitioned table, to which
the detached table is no longer related; this causes all sorts of
problems (such as inability of restoring a pg_dump of that table, and
the table no longer working properly if the partitioned table is later
dropped).
We'd like to get rid of all those constraints. In fact, for branch
master, do that -- no longer create any substitute constraints.
However, out of fear that some users might somehow depend on these
constraints for other partitioning strategies, for stable branches
(back to 14, which added DETACH CONCURRENTLY), only do it for hash
partitioning.
(If you repeatedly DETACH CONCURRENTLY and then ATTACH a partition, then
with this constraint addition you don't need to scan the table in the
ATTACH step, which presumably is good. But if users really valued this
feature, they would have requested that it worked for non-concurrent
DETACH also.)
Author: Haiyang Li <mohen.lhy@alibaba-inc.com>
Reported-by: Fei Changhong <feichanghong@qq.com>
Reported-by: Haiyang Li <mohen.lhy@alibaba-inc.com>
Backpatch-through: 14
Discussion: https://postgr.es/m/18371-7fef49f63de13f02@postgresql.org
Discussion: https://postgr.es/m/19070-781326347ade7c57@postgresql.org
An assertion in _bt_killitems expected the scan's currPos state to
contain a valid LSN, saved from when currPos's page was initially read.
The assertion failed to account for the fact that even logged relations
can have leaf pages with an invalid LSN when built with wal_level set to
"minimal". Remove the faulty assertion.
Oversight in commit e6eed40e (though note that the assertion was
backpatched to stable branches before 18 by commit 7c319f54).
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Matthijs van der Vleuten <postgresql@zr40.nl>
Bug: #19082
Discussion: https://postgr.es/m/19082-628e62160dbbc1c1@postgresql.org
Backpatch-through: 13
An error happening while a slot data is saved on disk in
SaveSlotToPath() could cause a state.tmp file (temporary file holding
the slot state data, renamed to its permanent name at the end of the
function) to remain around after it has been created. This temporary
file is created with O_EXCL, meaning that if an existing state.tmp is
found, its creation would fail. This would prevent the slot data to be
saved, requiring a manual intervention to remove state.tmp before being
able to save again a slot. Possible scenarios where this temporary file
could remain on disk is for example a ENOSPC case (no disk space) while
writing, syncing or renaming it. The bug reports point to a write
failure as the principal cause of the problems.
Using O_TRUNC has been argued back in 2019 as a potential solution to
discard any temporary file that could exist. This solution was rejected
as O_EXCL can also act as a safety measure when saving the slot state,
crash recovery offering cleanup guarantees post-crash. This commit uses
the alternative approach that has been suggested by Andres Freund back
in 2019. When the temporary state file cannot be written, synced,
closed or renamed (note: not when created!), an unlink() is used to
remove the temporary state file while holding the in-progress I/O
LWLock, so as any follow-up attempts to save a slot's data would not
choke on an existing file that remained around because of a previous
failure.
This problem has been reported a few times across the years, going back
to 2019, but for some reason I have never come back to do something
about it and it has been forgotten. A recent report has reminded me
that this was still a problem.
Reported-by: Kevin K Biju <kevinkbiju@gmail.com>
Reported-by: Sergei Kornilov <sk@zsrv.org>
Reported-by: Grigory Smolkin <g.smolkin@postgrespro.ru>
Discussion: https://postgr.es/m/CAM45KeHa32soKL_G8Vk38CWvTBeOOXcsxAPAs7Jt7yPRf2mbVA@mail.gmail.com
Discussion: https://postgr.es/m/3559061693910326@qy4q4a6esb2lebnz.sas.yp-c.yandex.net
Discussion: https://postgr.es/m/08bbfab1-a61d-3750-fc18-4ab2c1aa7f09@postgrespro.ru
Backpatch-through: 13
The processing of the PARALLEL option for VACUUM was not quite
following what the DefElem code had intended. defGetInt32() already has
code to handle missing parameters and returns a perfectly good error
message for when that happens.
Here we get rid of the ExecVacuum() error:
ERROR: parallel option requires a value between 0 and N
and leave defGetInt32() handle it, which will give:
ERROR: parallel requires an integer value
defGetInt32() was already handling the non-integer parameter case, so it
may as well handle the missing parameter case too.
Additionally, parameterize the option name to make translator work easier,
and also use errhint_internal() rather than errhint() for the
BUFFER_USAGE_LIMIT option since there isn't any work for a translator to
do for "%s".
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAApHDvovH14tNWB+WvP6TSbfi7-=TysQ9h5tQ5AgavwyWRWKHA@mail.gmail.com
An error context callback function might leak some memory into
ErrorContext, since those functions are run with ErrorContext as
current context. In the case where the elevel is ERROR, this is
no problem since the code level that catches the error should do
FlushErrorState to clean up, and that will reset ErrorContext.
However, if the elevel is less than ERROR then no such cleanup occurs.
In principle, repeated leaks while emitting log messages or client
notices could accumulate arbitrarily much leaked data, if no ERROR
occurs in the session.
To fix, let errfinish() perform an ErrorContext reset if it is
at the outermost error nesting level. (If it isn't, we'll delay
cleanup until the outermost nesting level is exited.)
The only actual leakage of this sort that I've been able to observe
within our regression tests was recently introduced by commit
f727b63e8. While it seems plausible that there are other such
leaks not reached in the regression tests, the lack of field
reports suggests that they're not a big problem. Accordingly,
I won't take the risk of back-patching this now. We can always
back-patch later if we get field reports of leaks.
Reported-by: Andres Freund <andres@anarazel.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/jngsjonyfscoont4tnwi2qoikatpd5hifsg373vmmjvugwiu6g@m6opxh7uisgd
While pgoutput caches relation synchronization information in
RelationSyncCache that resides in CacheMemoryContext, each entry's
information (such as row filter expressions and column lists) is
stored in the entry's private memory context (entry_cxt in
RelationSyncEntry), which is a descendant memory context of the
decoding context. If a logical decoding invoked via SQL functions like
pg_logical_slot_get_binary_changes fails with an error, subsequent
logical decoding executions could access already-freed memory of the
entry's cache, resulting in a crash.
With this change, it's ensured that RelationSyncCache is cleaned up
even in error cases by using a memory context reset callback function.
Backpatch to 15, where entry_cxt was introduced for column filtering
and row filtering.
While the backbranches v13 and v14 have a similar issue where
RelationSyncCache persists even after an error when pgoutput is used
via SQL API, we decided not to backport this fix. This decision was
made because v13 is approaching its final minor release, and we won't
have an chance to fix any new issues that might arise. Additionally,
since using pgoutput via SQL API is not a common use case, the risk
outwights the benefit. If we receive bug reports, we can consider
backporting the fixes then.
Author: vignesh C <vignesh21@gmail.com>
Co-authored-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://postgr.es/m/CALDaNm0x-aCehgt8Bevs2cm=uhmwS28MvbYq1=s2Ekf0aDPkOA@mail.gmail.com
Backpatch-through: 15
Some of the buildfarm is still unhappy with WinGetFuncArgInPartition
even after 2273fa32b. While it seems to be just very old compilers,
we can suppress the warnings and arguably make the code more readable
by not initializing these variables till closer to where they are
used. While at it, make a couple of cosmetic comment improvements.
This patch adds support for the ALL SEQUENCES clause in publications,
enabling synchronization/replication of all sequences that is useful for
upgrades.
Publications can now include all sequences via FOR ALL SEQUENCES.
psql enhancements:
\d shows publications for a given sequence.
\dRp indicates if a publication includes all sequences.
ALL SEQUENCES can be combined with ALL TABLES, but not with other options
like TABLE or TABLES IN SCHEMA. We can extend support for more granular
clauses in future.
The view pg_publication_sequences provides information about the mapping
between publications and sequences.
This patch enables publishing of sequences; subscriber-side support will
be added in upcoming patches.
Author: vignesh C <vignesh21@gmail.com>
Author: Tomas Vondra <tomas@vondra.me>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CAA4eK1LC+KJiAkSrpE_NwvNdidw9F2os7GERUeSxSKv71gXysQ@mail.gmail.com
SQL/JSON functions such as JSON_VALUE could fail with "unrecognized
node type" errors when a DEFAULT clause contained an explicit COLLATE
expression. That happened because assign_collations_walker() could
invoke exprSetCollation() on a JsonBehavior expression whose DEFAULT
still contained a CollateExpr, which exprSetCollation() does not
handle.
For example:
SELECT JSON_VALUE('{"a":1}', '$.c' RETURNING text
DEFAULT 'A' COLLATE "C" ON EMPTY);
Fix by validating in transformJsonBehavior() that the DEFAULT
expression's collation matches the enclosing JSON expression’s
collation. In exprSetCollation(), replace the recursive call on the
JsonBehavior expression with an assertion that its collation already
matches the target, since the parser now enforces that condition.
Reported-by: Jian He <jian.universality@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CACJufxHVwYYSyiVQ6o+PsRX6zQ7rAFinh_fv1kCfTsT1xG4Zeg@mail.gmail.com
Backpatch-through: 17
truncate_useless_pathkeys() seems to have neglected to account for
PathKeys that might be useful for WindowClause evaluation. Modify it so
that it properly accounts for that.
Making this work required adjusting two things:
1. Change from checking query_pathkeys to check sort_pathkeys instead.
2. Add explicit check for window_pathkeys
For #1, query_pathkeys gets set in standard_qp_callback() according to the
sort order requirements for the first operation to be applied after the
join planner is finished, so this changes depending on which upper
planner operations a particular query needs. If the query has window
functions and no GROUP BY, then query_pathkeys gets set to
window_pathkeys. Before this change, this meant PathKeys useful for the
ORDER BY were not accounted for in queries with window functions.
Because of #1, #2 is now required so that we explicitly check to ensure
we don't truncate away PathKeys useful for window functions.
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvrj3HTKmXoLMbUjTO=_MNMxM=cnuCSyBKidAVibmYPnrg@mail.gmail.com
Previously StrategyGetBuffer() acquired the buffer header spinlock for every
buffer, whether it was reusable or not. If reusable, it'd be returned, with
the lock held, to GetVictimBuffer(), which then would pin the buffer with
PinBuffer_Locked(). That's somewhat violating the spirit of the guidelines for
holding spinlocks (i.e. that they are only held for a few lines of consecutive
code) and necessitates using PinBuffer_Locked(), which scales worse than
PinBuffer() due to holding the spinlock. This alone makes it worth changing
the code.
However, the main reason to change this is that a future commit will make
PinBuffer_Locked() slower (due to making UnlockBufHdr() slower), to gain
scalability for the much more common case of pinning a pre-existing buffer. By
pinning the buffer with a single atomic operation, iff the buffer is reusable,
we avoid any potential regression for miss-heavy workloads. There strictly are
fewer atomic operations for each potential buffer after this change.
The price for this improvement is that freelist.c needs two CAS loops and
needs to be able to set up the resource accounting for pinned buffers. The
latter is achieved by exposing a new function for that purpose from bufmgr.c,
that seems better than exposing the entire private refcount infrastructure.
The improvement seems worth the complexity.
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/fvfmkr5kk4nyex56ejgxj3uzi63isfxovp2biecb4bspbjrze7@az2pljabhnff
We're planning to merge buffer content locks into BufferDesc.state. To reduce
the size of that patch, centralize calls to BufferDescriptorGetContentLock().
The biggest part of the change is in assertions, by introducing
BufferIsLockedByMe[InMode]() (and removing BufferIsExclusiveLocked()). This
seems like an improvement even without aforementioned plans.
Additionally replace some direct calls to LWLockAcquire() with calls to
LockBuffer().
Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/fvfmkr5kk4nyex56ejgxj3uzi63isfxovp2biecb4bspbjrze7@az2pljabhnff
BM_PERMANENT is defined as 1U<<31, which is a negative number when interpreted
as a signed integer. Unfortunately the mask variable in BufferSync() was
signed. This has been wrong for a long time, but failed to fail, due to
integer conversion rules.
However, in an upcoming patch the width of the state variable will be
increased, with the wrong signedness leading to never flushing permanent
buffers - luckily caught in a test.
It seems better to fix this separately, instead of doing so as part of a
large, otherwise mechanical, patch.
Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/fvfmkr5kk4nyex56ejgxj3uzi63isfxovp2biecb4bspbjrze7@az2pljabhnff
While testing a new potential use for ReadRecentBuffer(), Andres
reported that it scales badly when called concurrently for the same
buffer by many backends. Instead of a naive (but wrong) coding with
PinBuffer(), it used the spinlock, so that it could be careful to pin
only if the buffer was valid and holding the expected block, to avoid
breaking invariants in eg GetVictimBuffer(). Unfortunately that made it
less scalable than PinBuffer(), which uses compare-exchange instead.
We can fix that by giving PinBuffer() a new skip_if_not_valid mode that
doesn't pin invalid buffers. It might occasionally skip when it
shouldn't due to the unlocked read of the header flags, but that's
unlikely and perfectly acceptable for an opportunistic optimisation
routine, and it can only succeed when it really should due to the
compare-exchange loop.
Note that this fixes ReadRecentBuffer()'s failure to bump the usage
count. While this could be seen as a bug, there currently aren't cases
affected by this in core, so it doesn't seem worth backpatching that portion.
Author: Thomas Munro <thomas.munro@gmail.com>
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/20230627020546.t6z4tntmj7wmjrfh%40awork3.anarazel.de
Discussion: https://postgr.es/m/fvfmkr5kk4nyex56ejgxj3uzi63isfxovp2biecb4bspbjrze7@az2pljabhnff
These hooks allow plugins to get control at the earliest point at
which the PlannerGlobal object is fully initialized, and then just
before it gets destroyed. This is useful in combination with the
extendable plan state facilities (see extendplan.h) and perhaps for
other purposes as well.
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CA+TgmoYWKHU2hKr62Toyzh-kTDEnMDeLw7gkOOnjL-TnOUq0kQ@mail.gmail.com
This allows extensions to have access to any data they've stored
in the ExplainState during planning. Unfortunately, it won't help
with EXPLAIN EXECUTE is used, but since that case is less common,
this still seems like an improvement.
Since planner() has quite a few arguments now, also add some
documentation of those arguments and the return value.
Author: Robert Haas <rhaas@postgresql.org>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CA+TgmoYWKHU2hKr62Toyzh-kTDEnMDeLw7gkOOnjL-TnOUq0kQ@mail.gmail.com
Eager aggregation is a query optimization technique that partially
pushes aggregation past a join, and finalizes it once all the
relations are joined. Eager aggregation may reduce the number of
input rows to the join and thus could result in a better overall plan.
In the current planner architecture, the separation between the
scan/join planning phase and the post-scan/join phase means that
aggregation steps are not visible when constructing the join tree,
limiting the planner's ability to exploit aggregation-aware
optimizations. To implement eager aggregation, we collect information
about aggregate functions in the targetlist and HAVING clause, along
with grouping expressions from the GROUP BY clause, and store it in
the PlannerInfo node. During the scan/join planning phase, this
information is used to evaluate each base or join relation to
determine whether eager aggregation can be applied. If applicable, we
create a separate RelOptInfo, referred to as a grouped relation, to
represent the partially-aggregated version of the relation and
generate grouped paths for it.
Grouped relation paths can be generated in two ways. The first method
involves adding sorted and hashed partial aggregation paths on top of
the non-grouped paths. To limit planning time, we only consider the
cheapest or suitably-sorted non-grouped paths in this step.
Alternatively, grouped paths can be generated by joining a grouped
relation with a non-grouped relation. Joining two grouped relations
is currently not supported.
To further limit planning time, we currently adopt a strategy where
partial aggregation is pushed only to the lowest feasible level in the
join tree where it provides a significant reduction in row count.
This strategy also helps ensure that all grouped paths for the same
grouped relation produce the same set of rows, which is important to
support a fundamental assumption of the planner.
For the partial aggregation that is pushed down to a non-aggregated
relation, we need to consider all expressions from this relation that
are involved in upper join clauses and include them in the grouping
keys, using compatible operators. This is essential to ensure that an
aggregated row from the partial aggregation matches the other side of
the join if and only if each row in the partial group does. This
ensures that all rows within the same partial group share the same
"destiny", which is crucial for maintaining correctness.
One restriction is that we cannot push partial aggregation down to a
relation that is in the nullable side of an outer join, because the
NULL-extended rows produced by the outer join would not be available
when we perform the partial aggregation, while with a
non-eager-aggregation plan these rows are available for the top-level
aggregation. Pushing partial aggregation in this case may result in
the rows being grouped differently than expected, or produce incorrect
values from the aggregate functions.
If we have generated a grouped relation for the topmost join relation,
we finalize its paths at the end. The final paths will compete in the
usual way with paths built from regular planning.
The patch was originally proposed by Antonin Houska in 2017. This
commit reworks various important aspects and rewrites most of the
current code. However, the original patch and reviews were very
useful.
Author: Richard Guo <guofenglinux@gmail.com>
Author: Antonin Houska <ah@cybertec.at> (in an older version)
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me> (in an older version)
Reviewed-by: Andy Fan <zhihuifan1213@163.com> (in an older version)
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com> (in an older version)
Discussion: https://postgr.es/m/CAMbWs48jzLrPt1J_00ZcPZXWUQKawQOFE8ROc-ADiYqsqrpBNw@mail.gmail.com
It is possible to call pg_stat_reset_single_function_counters() for a
single function, but the reset time was missing the system view showing
its statistics. Like all the fields of pg_stat_user_functions, the GUC
track_functions needs to be enabled to show the statistics about
function executions.
Bump catalog version.
Bump PGSTAT_FILE_FORMAT_ID, as a result of the new field added to
PgStat_StatFuncEntry.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aONjnsaJSx-nEdfU@paquier.xyz
Fix several issues pointed out by Coverity (reported by Tome Lane).
- In row_is_in_frame(), return value of window_gettupleslot() was not
checked.
- WinGetFuncArgInPartition() tried to derefference "isout" pointer
even if it could be NULL in some places.
Besides the issues, I also fixed a compiler warning reported by Álvaro
Herrera.
Moreover, in WinGetFuncArgInPartition refactor the do...while loop so
that the codes inside the loop simpler. Also simplify the case when
abs_pos < 0.
Author: Tatsuo Ishii <ishii@postgresql.org>
Reviewed-by: Paul Ramsey <pramsey@cleverelephant.ca>
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/1686755.1759679957%40sss.pgh.pa.us
Discussion: https://postgr.es/m/202510051612.gw67jlc2iqpw%40alvherre.pgsql
Instead, use the new mechanism that allows planner extensions to store
private state inside a PlannerInfo, treating GEQO as an in-core planner
extension. This is a useful test of the new facility, and also buys
back a few bytes of storage.
To make this work, we must remove innerrel_is_unique_ext's hack of
testing whether join_search_private is set as a proxy for whether
the join search might be retried. Add a flag that extensions can
use to explicitly signal their intentions instead.
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CA+TgmoYWKHU2hKr62Toyzh-kTDEnMDeLw7gkOOnjL-TnOUq0kQ@mail.gmail.com
Extension that make extensive use of planner hooks may want to
coordinate their efforts, for example to avoid duplicate computation,
but that's currently difficult because there's no really good way to
pass data between different hooks.
To make that easier, allow for storage of extension-managed private
state in PlannerGlobal, PlannerInfo, and RelOptInfo, along very
similar lines to what we have permitted for ExplainState since commit
c65bc2e1d1.
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CA+TgmoYWKHU2hKr62Toyzh-kTDEnMDeLw7gkOOnjL-TnOUq0kQ@mail.gmail.com
Previously, subqueries were given names only after they were planned,
which makes it difficult to use information from a previous execution of
the query to guide future planning. If, for example, you knew something
about how you want "InitPlan 2" to be planned, you won't know whether
the subquery you're currently planning will end up being "InitPlan 2"
until after you've finished planning it, by which point it's too late to
use the information that you had.
To fix this, assign each subplan a unique name before we begin planning
it. To improve consistency, use textual names for all subplans, rather
than, as we did previously, a mix of numbers (such as "InitPlan 1") and
names (such as "CTE foo"), and make sure that the same name is never
assigned more than once.
We adopt the somewhat arbitrary convention of using the type of sublink
to set the plan name; for example, a query that previously had two
expression sublinks shown as InitPlan 2 and InitPlan 1 will now end up
named expr_1 and expr_2. Because names are assigned before rather than
after planning, some of the regression test outputs show the numerical
part of the name switching positions: what was previously SubPlan 2 was
actually the first one encountered, but we finished planning it later.
We assign names even to subqueries that aren't shown as such within the
EXPLAIN output. These include subqueries that are a FROM clause item or
a branch of a set operation, rather than something that will be turned
into an InitPlan or SubPlan. The purpose of this is to make sure that,
below the topmost query level, there's always a name for each subquery
that is stable from one planning cycle to the next (assuming no changes
to the query or the database schema).
Author: Robert Haas <rhaas@postgresql.org>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: http://postgr.es/m/3641043.1758751399@sss.pgh.pa.us
When either inputs of an INTERSECT [ALL] operator are proven not to return
any results (a dummy rel), then mark the entire INTERSECT operation as
dummy.
Likewise, if an EXCEPT [ALL] operation's left input is proven empty, then
mark the entire operation as dummy.
With EXCEPT ALL, we can easily handle the right input being dummy as
we can return the left input without any processing. That can lead to
significant performance gains during query execution. We can't easily
handle dummy right inputs for EXCEPT (without ALL), as that would require
deduplication of the left input. Wiring up those Paths is likely more
complex than it's worth as the gains during execution aren't that great,
so let's leave that one to be handled by the normal Path generation code.
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAApHDvri53PPF76c3M94_QNWbJfXjyCnjXuj_2=LYM-0m8WZtw@mail.gmail.com
The prior code, added in 03d40e4b5 attempted to use the targetlist of the
first UNION child when all UNION children were proven as dummy rels.
That's not going to work when some operation atop of the Result node must
find target entries within the Result's targetlist. This could have been
something as simple as trying to sort the results of the UNION operation,
which would lead to:
ERROR: could not find pathkey item to sort
Instead, use the top-level UNION's targetlist and fix the varnos in
setrefs.c. Because set operation targetlists always use varno==0, we
can rewrite those to become varno==1, i.e. use the Vars from the first
UNION child. This does result in showing Vars from relations that are
not present in the final plan, but that's no different to what we see
when normal base relations are proven dummy.
Without this fix it would be possible to see the following error in
EXPLAIN VERBOSE when all UNION inputs were proven empty.
ERROR: bogus varno: 0
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvrUASy9sfULMEsM2udvZJP6AoBRCZvHYXYxZTy2tX9FYw@mail.gmail.com
Previously, we attempted to form a posting list tuple even when
ginCompressPostingList() failed to compress the posting list due to
its size. While there was no functional failure, it always wasted one
GinFormTuple() call when item pointers didn't fit in a posting list
tuple.
This commit ensures that a GIN index tuple is formed only when all
item pointers in the posting list are successfully compressed.
Author: Arseniy Mukhin <arseniy.mukhin.dev@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAE7r3M+C=jcpTD93f_RBHrQp3C+=TAXFs+k4tTuZuuxboK8AvA@mail.gmail.com
The hex_encode() and hex_decode() functions serve as the workhorses
for hexadecimal data for bytea's text format conversion functions,
and some workloads are sensitive to their performance. This commit
adds new implementations that use routines from port/simd.h, which
testing indicates are much faster for larger inputs. For small or
invalid inputs, we fall back on the existing scalar versions.
Since we are using port/simd.h, these optimizations apply to both
x86-64 and AArch64.
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Chiranmoy Bhattacharya <chiranmoy.bhattacharya@fujitsu.com>
Co-authored-by: Susmitha Devanga <devanga.susmitha@fujitsu.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/aLhVWTRy0QPbW2tl%40nathan
The WAL records XLOG_GIN_INSERT and XLOG_GIN_VACUUM_DATA_LEAF_PAGE
included some information about the blocks added to the record.
This information is already provided by XLogRecGetBlockRefInfo() with
much more details about the blocks included in each record, like the
compression information, for example. This commit removes the block
information that existed in the record descriptions specific to GIN.
Author: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/CALdSSPgk=9WRoXhZy5fdk+T1hiau7qbL_vn94w_L1N=gtEdbsg@mail.gmail.com
It is possible to call pg_stat_reset_single_table_counters() on a
relation (index or table) but the reset time was missing from the system
views showing their statistics.
This commit adds the reset time as an attribute of pg_stat_all_tables,
pg_stat_all_indexes, and other relations related to them.
Bump catalog version.
Bump PGSTAT_FILE_FORMAT_ID, as a result of the new field added to
PgStat_StatTabEntry.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/aN8l182jKxEq1h9f@paquier.xyz
This adjusts UNION planning so that the planner produces more optimal
plans when one or more of the UNION's subqueries have been proven to be
empty (a dummy rel).
If any of the inputs are empty, then that input can be removed from the
Append / MergeAppend. Previously, a const-false "Result" node would
appear to represent this. Removing empty inputs has a few extra
benefits when only 1 union child remains as it means the Append or
MergeAppend can be removed in setrefs.c, making the plan slightly faster
to execute. Also, we can provide better n_distinct estimates by looking
at the sole remaining input rel's statistics.
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAApHDvri53PPF76c3M94_QNWbJfXjyCnjXuj_2=LYM-0m8WZtw@mail.gmail.com
bms_union() causes a new set to be allocated. What this caller needs is
members added to an existing set. bms_add_members() is the tool for
that job.
This is just a matter of fixing an inefficiency due to surplus memory
allocations. No bugs being fixed.
The only other place I found that might be valid to apply this change is
in markNullableIfNeeded(), but I opted not to do that due to the risk to
reward ratio not looking favorable. The risk being that there *could* be
another pointer pointing to the Bitmapset.
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Greg Burd <greg@burd.me>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAApHDvoCcoS-p5tZNJLTxFOKTYNjqVh7Dwf+5ikDUBwnvWftRw@mail.gmail.com
Make some use of anonymous unions, which are allowed as of C11, as
examples and encouragement for future code, and to test compilers.
This commit changes the DSMRegistryEntry struct.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/aNKsDg0fJwqhZdXX%40nathan
In similar vein to commit ccc8194e42, a reset instance of a shared
memory TID store happened to occupy the same private memory as the old
one for the entry point, since the chunk freed after the last round
of index vacuuming was put on the context's freelist. The failure
to update the vacrel->dead_items pointer was evident by nudging the
system to allocate memory in a different area. This was not discovered
at the time of the earlier commit since our regression tests didn't
cover multiple index passes with parallel vacuum.
Backpatch to v17, when TidStore came in.
Author: Kevin Oommen Anish <kevin.o@zohocorp.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Tested-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/199a07cbdfc.7a1c4aac25838.1675074408277594551%40zohocorp.com
Backpatch-through: 17
Add IGNORE NULLS/RESPECT NULLS option (null treatment clause) to lead,
lag, first_value, last_value and nth_value window functions. If
unspecified, the default is RESPECT NULLS which includes NULL values
in any result calculation. IGNORE NULLS ignores NULL values.
Built-in window functions are modified to call new API
WinCheckAndInitializeNullTreatment() to indicate whether they accept
IGNORE NULLS/RESPECT NULLS option or not (the API can be called by
user defined window functions as well). If WinGetFuncArgInPartition's
allowNullTreatment argument is true and IGNORE NULLS option is given,
WinGetFuncArgInPartition() or WinGetFuncArgInFrame() will return
evaluated function's argument expression on specified non NULL row (if
it exists) in the partition or the frame.
When IGNORE NULLS option is given, window functions need to visit and
evaluate same rows over and over again to look for non null rows. To
mitigate the issue, 2-bit not null information array is created while
executing window functions to remember whether the row has been
already evaluated to NULL or NOT NULL. If already evaluated, we could
skip the evaluation work, thus we could get better performance.
Author: Oliver Ford <ojford@gmail.com>
Co-authored-by: Tatsuo Ishii <ishii@postgresql.org>
Reviewed-by: Krasiyan Andreev <krasiyan@gmail.com>
Reviewed-by: Andrew Gierth <andrew@tao11.riddles.org.uk>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Fetter <david@fetter.org>
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Reviewed-by: "David G. Johnston" <david.g.johnston@gmail.com>
Reviewed-by: Chao Li <lic@highgo.com>
Discussion: https://postgr.es/m/flat/CAGMVOdsbtRwE_4+v8zjH1d9xfovDeQAGLkP_B6k69_VoFEgX-A@mail.gmail.com
