This request allows a support function to replace a function call
appearing in FROM (typically a set-returning function) with an
equivalent SELECT subquery. The subquery will then be subject
to the planner's usual optimizations, potentially allowing a much
better plan to be generated. While the planner has long done this
automatically for simple SQL-language functions, it's now possible
for extensions to do it for functions outside that group.
Notably, this could be useful for functions that are presently
implemented in PL/pgSQL and work by generating and then EXECUTE'ing
a SQL query.
Author: Paul A Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/09de6afa-c33d-4d94-a5cb-afc6cea0d2bb@illuminatedcomputing.com
The existing range_minus function raises an exception when the range is
"split", because then the result can't be represented by a single range.
For example '[0,10)'::int4range - '[4,5)' would be '[0,4)' and '[5,10)'.
This commit adds new set-returning functions so that callers can get
results even in the case of splits. There is no risk of an exception for
multiranges, but a set-returning function lets us handle them the same
way we handle ranges.
Both functions return zero results if the subtraction would give an
empty range/multirange.
The main use-case for these functions is to implement UPDATE/DELETE FOR
PORTION OF, which must compute the application-time of "temporal
leftovers": the part of history in an updated/deleted row that was not
changed. To preserve the untouched history, we will implicitly insert
one record for each result returned by range/multirange_minus_multi.
Using a set-returning function will also let us support user-defined
types for application-time update/delete in the future.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/ec498c3d-5f2b-48ec-b989-5561c8aa2024%40illuminatedcomputing.com
There was no easy way to run specific tests in the meson based builds.
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: postgr.es/m/CAExHW5tK-QqayUN0%2BN3MF5bjV6vLKDCkRuGwoDJwc7vGjwCygQ%40mail.gmail.com
Makes the code a little simpler.
The old implementation accepted trailing whitespace, but that was
unnecessary. Firstly, its sibling function for parsing decimals,
strtodouble(), does not accept trailing whitespace. Secondly, none of
the callers can pass a string with trailing whitespace to it.
In the passing, check specifically for ERANGE before printing the "out
of range" error. On some systems, strtoul() and strtod() return EINVAL
on an empty or all-spaces string, and "invalid input syntax" is more
appropriate for that than "out of range". For the existing
strtodouble() function this is purely academical because it's never
called with errorOK==false, but let's be tidy. (Perhaps we should
remove the dead codepaths altogether, but I'll leave that for another
day.)
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: Yuefei Shi <shiyuefei1004@gmail.com>
Reviewed-by: Neil Chen <carpenter.nail.cz@gmail.com>
Discussion: https://www.postgresql.org/message-id/861dd5bd-f2c9-4ff5-8aa0-f82bdb75ec1f@iki.fi
This changes a few union members that only existed to ensure
alignments and replaces them with the C11 alignas specifier.
This change only uses fundamental alignments (meaning approximately
alignments of basic types), which all C11 compilers must support.
There are opportunities for similar changes using extended alignments,
for example in PGIOAlignedBlock, but these are not necessarily
supported by all compilers, so they are kept as a separate change.
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/46f05236-d4d4-4b4e-84d4-faa500f14691%40eisentraut.org
This conforms more closely with the style of other struct initializers
in the code base. Initializing multiple fields on a single line is
unpopular in part because pgindent won't permit a space after the comma
before the next field's period.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reported-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://postgr.es/m/87see87fnq.fsf%40wibble.ilmari.org
This generates a more accurate code count because 'make distclean'
doesn't always remove build files.
Author: idea from David Rowley
Discussion: https://postgr.es/m/aR4hoOotVHB7TXo5@momjian.us
Backpatch-through: master
During pruning and freezing in phase I of vacuum, we delay clearing
all_visible and all_frozen in the presence of dead items. This allows
opportunistic freezing if the page would otherwise be fully frozen,
since those dead items are later removed in vacuum phase III.
To move the VM update into the same WAL record that
prunes and freezes tuples, we must know whether the page will
be marked all-visible/all-frozen before emitting WAL. Previously we
waited until after emitting WAL to update all_visible/all_frozen to
their correct values.
The only barrier to updating these flags immediately after deciding
whether to opportunistically freeze was that while emitting WAL for a
record freezing tuples, we use the pre-corrected value of all_frozen to
compute the snapshot conflict horizon. By determining the conflict
horizon earlier, we can update the flags immediately after making the
opportunistic freeze decision.
This is required to set the VM in the XLOG_HEAP2_PRUNE_VACUUM_SCAN
record emitted by pruning and freezing.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZMw6Npd_qm2KM%2BFwQ3cMOMx1Dh3VMhp8-V7SOLxdK9-g%40mail.gmail.com
When running in Docker, the container may not have privileges needed by
get_mempolicy(). This is called by numa_available() in libnuma, but
versions prior to 2.0.19 did not expect that. The numa_available() call
seemingly succeeds, but then we get unexpected failures when trying to
query status of pages:
postgres =# select * from pg_shmem_allocations_numa;
ERROR: XX000: failed NUMA pages inquiry status: Operation not
permitted
LOCATION: pg_get_shmem_allocations_numa, shmem.c:691
The best solution is to call get_mempolicy() first, and proceed to
numa_available() only when it does not fail with EPERM. Otherwise we'd
need to treat older libnuma versions as insufficient, which seems a bit
too harsh, as this only affects containerized systems.
Fix by me, based on suggestions by Christoph. Backpatch to 18, where the
NUMA functions were introduced.
Reported-by: Christoph Berg <myon@debian.org>
Reviewed-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/aPDZOxjrmEo_1JRG@msg.df7cb.de
Backpatch-through: 18
The upstream timezone code uses a bool variable as an array subscript.
Back when PostgreSQL's bool was char, this would have caused a warning
from gcc -Wchar-subscripts, which is included in -Wall. But this has
been obsolete since probably commit d26a810ebf, but certainly since
bool is now the C standard bool. So we can remove this deviation from
the upstream code, to make future code merges simpler.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/9ad2749f-77ab-4ecb-a321-1ca915480b05%40eisentraut.org
Commit 792353f7d5 updated the pg_dump and pg_dumpall documentation to
clarify which statistics are not included in their output. The pg_upgrade
documentation contained a nearly identical description, but it was not updated
at the same time.
This commit updates the pg_upgrade documentation to match those changes.
Backpatch to v18, where commit 792353f7d5 was backpatched to.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Bruce Momjian <bruce@momjian.us>
Discussion: https://postgr.es/m/CAHGQGwFnfgdGz8aGWVzgFCFwoWQU7KnFFjmxinf4RkQAkzmR+w@mail.gmail.com
Backpatch-through: 18
MSVCRT predated C99 and invented non-standard placeholders for 64-bit
numbers, and then later used them in standard macros when C99
<inttypes.h> arrived. The macros just use %lld etc when building with
UCRT, so there should be no way for our interposed sprintf.c code to
receive the pre-standard kind these days. Time to drop the code that
parses them.
That code was in fact already dead when commit 962da900 landed, as we'd
disclaimed MSVCRT support a couple of weeks earlier in commit 1758d424,
but patch development overlapped and the history of these macros hadn't
been investigated.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/4d8b1a67-aab2-4429-b44b-f03988095939%40eisentraut.org
If both sides of the operator have most-common-value statistics,
eqjoinsel wants to check which MCVs have matches on the other side.
Formerly it did this with a dumb compare-all-the-entries loop,
which had O(N^2) behavior for long MCV lists. When that code was
written, twenty-plus years ago, that seemed tolerable; but nowadays
people frequently use much larger statistics targets, so that the
O(N^2) behavior can hurt quite a bit.
To add insult to injury, when asked for semijoin semantics, the
entire comparison loop was done over, even though we frequently
know that it will yield exactly the same results.
To improve matters, switch to using a hash table to perform the
matching. Testing suggests that depending on the data type, we may
need up to about 100 MCVs on each side to amortize the extra costs
of setting up the hash table and performing hash-value computations;
so continue to use the old looping method when there are fewer MCVs
than that.
Also, refactor so that we don't repeat the matching work unless
we really need to, which occurs only in the uncommon case where
eqjoinsel_semi decides to truncate the set of inner MCVs it
considers. The refactoring also got rid of the need to use the
presented operator's commutator. Real-world operators that are
using eqjoinsel should pretty much always have commutators, but
at the very least this saves a few syscache lookups.
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Co-authored-by: David Geier <geidav.pg@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20ea8bf5-3569-4e46-92ef-ebb2666debf6@tantorlabs.com
The fix for bug #19055 (commit b0cc0a71e) allowed CTE references in
sub-selects within aggregate functions to affect the semantic levels
assigned to such aggregates. It turns out this broke some related
cases, leading to assertion failures or strange planner errors such
as "unexpected outer reference in CTE query". After experimenting
with some alternative rules for assigning the semantic level in
such cases, we've come to the conclusion that changing the level
is more likely to break things than be helpful.
Therefore, this patch undoes what b0cc0a71e changed, and instead
installs logic to throw an error if there is any reference to a
CTE that's below the semantic level that standard SQL rules would
assign to the aggregate based on its contained Var and Aggref nodes.
(The SQL standard disallows sub-selects within aggregate functions,
so it can't reach the troublesome case and hence has no rule for
what to do.)
Perhaps someone will come along with a legitimate query that this
logic rejects, and if so probably the example will help us craft
a level-adjustment rule that works better than what b0cc0a71e did.
I'm not holding my breath for that though, because the previous
logic had been there for a very long time before bug #19055 without
complaints, and that bug report sure looks to have originated from
fuzzing not from real usage.
Like b0cc0a71e, back-patch to all supported branches, though
sadly that no longer includes v13.
Bug: #19106
Reported-by: Kamil Monicz <kamil@monicz.dev>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19106-9dd3668a0734cd72@postgresql.org
Backpatch-through: 14
This file is written for 8-space tabs, since we expect that most
users who edit their configuration files use 8-space tabs.
However, most of PostgreSQL is written for 4-space tabs, and at
least one popular web interface defaults to 4-space tabs. Rather
than trying to standardize on a particular tab width for this file,
let's just switch to spaces.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/aReNUKdMgKxLqmq7%40nathan
This patch renames the sync_error_count column to sync_table_error_count
in the pg_stat_subscription_stats view. The new name makes the purpose
explicit now that a separate column exists to track sequence
synchronization errors.
Additionally, the column seq_sync_error_count is renamed to
sync_seq_error_count to maintain a consistent naming pattern, making it
easier for users to group, and query synchronization related counters.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/CALDaNm3WwJmz=-4ybTkhniB-Nf3qmFG9Zx1uKjyLLoPF5NYYXA@mail.gmail.com
Remove bogus stripping of RelabelTypes: that can result in building
an output SAOP tree with incorrect exposed exprType for the operands,
which might confuse polymorphic operators. Moreover it demonstrably
prevents folding some OR-trees to SAOPs when the RHS expressions
have different base types that were coerced to the same type by
RelabelTypes.
Reduce prohibition on type_is_rowtype to just disallow type RECORD.
We need that because otherwise we would happily fold multiple RECORD
Consts into a RECORDARRAY Const even if they aren't the same record
type. (We could allow that perhaps, if we checked that they all have
the same typmod, but the case doesn't seem worth that much effort.)
However, there is no reason at all to disallow the transformation
for named composite types, nor domains over them: as long as we can
find a suitable array type we're good.
Remove some assertions that seem rather out of place (it's not
this code's duty to verify that the RestrictInfo structure is
sane). Rewrite some comments.
The issues with RelabelType stripping seem severe enough to
back-patch this into v18 where the code was introduced.
Author: Tender Wang <tndrwang@gmail.com>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAHewXN=aH7GQBk4fXU-WaEeVmQWUmBAeNyBfJ3VKzPphyPKUkQ@mail.gmail.com
Backpatch-through: 18
