This commit improves subject in two ways:
* It removes ugliness of 02f90879e7, which stores distance values and null
flags in two separate arrays after GISTSearchItem struct. Instead we pack
both distance value and null flag in IndexOrderByDistance struct. Alignment
overhead should be negligible, because we typically deal with at most few
"col op const" expressions in ORDER BY clause.
* It fixes handling of "col op NULL" expression in KNN-SP-GiST. Now, these
expression are not passed to support functions, which can't deal with them.
Instead, NULL result is implicitly assumed. It future we may decide to
teach support functions to deal with NULL arguments, but current solution is
bugfix suitable for backpatch.
Reported-by: Nikita Glukhov
Discussion: https://postgr.es/m/826f57ee-afc7-8977-c44c-6111d18b02ec%40postgrespro.ru
Author: Nikita Glukhov
Reviewed-by: Alexander Korotkov
Backpatch-through: 9.4
It's important users be able to know (without looking at the source code)
that running DDL or DDL-like commands can interrupt autovacuum which can
lead to a lot of dead tuples and hence slower database operations.
Reported-by: James Coleman
Author: James Coleman
Reviewed-by: Amit Kapila
Backpatch-through: 9.4
Discussion: https://postgr.es/m/CAAaqYe-XYyNwML1=f=gnd0qWg46PnvD=BDrCZ5-L94B887XVxQ@mail.gmail.com
1. Commit 7086be6e3 should have documented the limitation that the direct
modification is disabled when WCO constraints are present, but didn't,
which is definitely my fault. Update the documentation (Postgres 9.6
onwards).
2. Commit fc22b6623 should have documented the limitation that the direct
modification is disabled when generated columns are defined, but
didn't. Update the documentation (Postgres 12 onwards).
Author: Etsuro Fujita
Discussion: https://postgr.es/m/CAPmGK14AYCPunLb6TRz1CQsW5Le01Z2ox8LSOKH0P-cOVDcQRA%40mail.gmail.com
PostgreSQL has been unusable when built with xlc 13 and newer, which are
incompatible with our use of __fetch_and_add(). Back-patch to 9.5,
which introduced pg_atomic_fetch_add_u32().
Reviewed by Tom Lane.
Discussion: https://postgr.es/m/20190831071157.GA3251746@rfd.leadboat.com
Most WAL records are ignored in early SnapBuild snapshot build phases.
But it's critical to process some of them, so that later messages have
the correct transaction state after the snapshot is completely built; in
particular, XLOG_XACT_ASSIGNMENT messages are critical in order for
sub-transactions to be correctly assigned to their parent transactions,
or at least one assert misbehaves, as reported by Ildar Musin.
Diagnosed-by: Masahiko Sawada
Author: Masahiko Sawada
Discussion: https://postgr.es/m/CAONYFtOv+Er1p3WAuwUsy1zsCFrSYvpHLhapC_fMD-zNaRWxYg@mail.gmail.com
Lack of parens in the definitions could cause a statement using these
macros to have unexpected semantics. In current code no bug is
apparent, but best to fix the definitions to avoid problems down the
line.
Reported-by: Tom Lane
Discussion: https://postgr.es/m/19795.1568400476@sss.pgh.pa.us
Include newitemoff in rmgr desc output for nbtree page split records.
In passing, correct an obsolete comment that claimed that newitemoff is
only logged for _L variant nbtree page split WAL records.
Both issues were oversights in commit 2c03216d831, which revamped the
WAL format.
Author: Peter Geoghegan
Backpatch: 9.5-, where the WAL format was revamped.
Since WITH CHECK OPTION was introduced, ExecInitModifyTable has
initialized WCO expressions with the wrong plan node as parent -- that is,
it passed its input subplan not the ModifyTable node itself. Up to now
we thought this was harmless, but bug #16006 from Vinay Banakar shows it's
not: if the input node is a SubqueryScan then ExecInitWholeRowVar can get
confused into doing the wrong thing. (The fact that ExecInitWholeRowVar
contains such logic is certainly a horrid kluge that doesn't deserve to
live, but figuring out another way to do that is a task for some other day.)
Andres had already noticed the wrong-parent mistake and fixed it in commit
148e632c0, but not being aware of any user-visible consequences, he quite
reasonably didn't back-patch. This patch is simply a back-patch of
148e632c0, plus addition of a test case based on bug #16006. I also added
the test case to v12/HEAD, even though the bug is already fixed there.
Back-patch to all supported branches. 9.4 lacks RLS policies so the
new test case doesn't work there, but I'm pretty sure a test could be
devised based on using a whole-row Var in a plain WITH CHECK OPTION
condition. (I lack the cycles to do so myself, though.)
Andres Freund and Tom Lane
Discussion: https://postgr.es/m/16006-99290d2e4642cbd5@postgresql.org
Discussion: https://postgr.es/m/20181205225213.hiwa3kgoxeybqcqv@alap3.anarazel.de
9ee98cc3f added missing doc for pg_trgm.strict_word_similarity_threshold GUC.
But it was accidentally backpatched to 9.6, while this GUC was introduced only
in 11. This patch removes extra doc from 9.6 and 10.
Discussion: https://postgr.es/m/CAHE3wghn%3DRyPWY-nxX1SiYAfkuwLHMd9Z4r8v9ww_jSs1jF5pg%40mail.gmail.com
Author: Euler Taveira
Backpatch-through: 9.6 and 10
The example used to explain 'Looping Through Query Results' uses
pseudo-materialized views. Replace it with a more up-to-date example
which does the same thing with actual materialized views, which have
been available since PostgreSQL 9.3.
In the passing, change '%' as format specifier instead of '%s' as is used
in other examples in plpgsql.sgml.
Reported-by: Ian Barwick
Author: Ian Barwick
Reviewed-by: Amit Kapila
Backpatch-through: 9.4
Discussion: https://postgr.es/m/9a70d393-7904-4918-c97c-649f6d114b6a@2ndquadrant.com
Depending on the system used, t/*.pl may not be expanded into a list of
tests which can be consumed by prove when attempting to run TAP tests on
a given path. Fix that by using glob() directly in the script, to make
sure that a complete list of tests is provided. This has not proved to
be an issue with MSVC as the list was properly expanded, but it is on
Linux with perl's system().
This is extracted from a larger patch.
Author: Tom Lane
Discussion: https://postgr.es/m/6628.1567958876@sss.pgh.pa.us
Backpatch-through: 9.4
Back-patch relevant parts of these commits:
30717637c Fix isolationtester race condition for notices sent before blocking
ebd499282 Don't drop NOTICE messages in isolation tests
a28e10e82 Indicate session name in isolationtester notices
This ensures that older versions of the isolationtester will handle
NOTICE/WARNING messages the same way as HEAD and v12 do. While this
isn't fixing any critical problem right now, it seems like a prudent
change to prevent surprises (like we had yesterday...) with
back-patches of future isolation test changes.
Back-patch as far as 9.6. Due to the significant changes we made in
isolationtester in 9.6, back-patching isolation tests further than
that is going to be risky anyway; besides, this patch doesn't apply
cleanly before that.
Discussion: https://postgr.es/m/E1i7IqC-0000Uc-5H@gemulon.postgresql.org
Modern versions of msys2 have changed the treatment of "cmd /c" so that
the runtime will try to convert the switch to a native file path. This
patch adds a setting to inhibit that behaviour.
Discussion: https://postgr.es/m/3227042f-cfcc-745a-57dd-fb8c471f8ddf@2ndQuadrant.com
Backpatch to all live branches.
Some of these are quite old, but that doesn't make them not bugs.
We'd rather report a failure via elog than SIGSEGV.
While at it, uniformly spell the error check as !RelationIsValid(rel)
rather than a bare rel == NULL test. The machine code is the same
but it seems better to be consistent.
Coverity complained about this today, not sure why, because the
mistake is in fact old.
In order to implement NULL LAST semantic GiST previously assumed distance to
the NULL value to be Inf. However, our distance functions can return Inf and
NaN for non-null values. In such cases, NULL LAST semantic appears to be
broken. This commit fixes that by introducing separate array of null flags for
distances.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/CAPpHfdsNvNdA0DBS%2BwMpFrgwT6C3-q50sFVGLSiuWnV3FqOJuQ%40mail.gmail.com
Author: Alexander Korotkov
Backpatch-through: 9.4
Previously plain float comparison was used in GiST pairing heap. Such
comparison doesn't provide proper ordering for value sets containing Inf and Nan
values. This commit fixes that by usage of float8_cmp_internal(). Note, there
is remaining problem with NULL distances, which are represented as Inf in
pairing heap. It would be fixes in subsequent commit.
Backpatch to all supported versions.
Reported-by: Andrey Borodin
Discussion: https://postgr.es/m/CAPpHfdsNvNdA0DBS%2BwMpFrgwT6C3-q50sFVGLSiuWnV3FqOJuQ%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Heikki Linnakangas
Backpatch-through: 9.4
Some systems don't ship with "python" by default anymore, only
"python3" or "python2" or some combination, so include those in the
configure search.
Back-patch of commit 7291733ac. At the time that was only pushed
back as far as v10, because of concerns about interactions with
commit b21c569ce. Closer analysis shows that if we just
s/AC_PATH_PROG/AC_PATH_PROGS/, there is no effect on the older
branches' behavior when PYTHON is explicitly specified, so it should
be okay to back-patch: this will not break any configuration that
worked before. And the need to support platforms with only a
"python3" or "python2" executable is getting ever more urgent.
Original patch by Peter Eisentraut, back-patch analysis by me
Discussion: https://www.postgresql.org/message-id/flat/1457.1543184081%40sss.pgh.pa.us#c9cc1199338fd6a257589c6dcea6cf8d
The old code didn't differentiate between a read error and a
concurrent truncation. fread reports both of these by returning 0;
you have to use feof() or ferror() to distinguish between them,
which this code did not do.
It might be a better idea to use read() rather than fread() here,
so that we can display a less-generic error message, but I'm not
sure that would qualify as a back-patchable bug fix, so just do
this much for now.
Jeevan Chalke, reviewed by Jeevan Ladhe and by me.
Discussion: http://postgr.es/m/CA+TgmobG4ywMzL5oQq2a8YKp8x2p3p1LOMMcGqpS7aekT9+ETA@mail.gmail.com
The logic ending progress reporting for a backend entry introduced by
b6fb647 causes callers of pgstat_progress_end_command() to do some extra
work when track_activities is enabled as the process fields are reset in
the backend entry even if no command were started for reporting.
This resets the fields only if a command is registered for progress
reporting, and only if track_activities is enabled.
Author: Masahiho Sawada
Discussion: https://postgr.es/m/CAD21AoCry_vJ0E-m5oxJXGL3pnos-xYGCzF95rK5Bbi3Uf-rpA@mail.gmail.com
Backpatch-through: 9.6
After an unexpected connection loss and successful reconnection,
psql neglected to resynchronize its internal state about the server,
such as server version. Ordinarily we'd be reconnecting to the same
server and so this isn't really necessary, but there are scenarios
where we do need to update --- one example is where we have a list
of possible connection targets and they're not all alike.
Define "resynchronize" as including connection_warnings(), so that
this case acts the same as \connect. This seems useful; for example,
if the server version did change, the user might wish to know that.
An attuned user might also notice that the new connection isn't
SSL-encrypted, for example, though this approach isn't especially
in-your-face about such changes. Although this part is a behavioral
change, it only affects interactive sessions, so it should not break
any applications.
Also, in do_connect, make sure that we desynchronize correctly when
abandoning an old connection in non-interactive mode.
These problems evidently are the result of people patching only one
of the two places where psql deals with connection changes, so insert
some cross-referencing comments in hopes of forestalling future bugs
of the same ilk.
Lastly, in Windows builds, issue codepage mismatch warnings only at
startup, not during reconnections. psql's codepage can't change
during a reconnect, so complaining about it again seems like useless
noise.
Peter Billen and Tom Lane. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAMTXbE8e6U=EBQfNSe01Ej17CBStGiudMAGSOPaw-ALxM-5jXg@mail.gmail.com
The comment did not match what the code actually did for integers with
the 43rd bit set. You get an integer like that, if you have a posting
list with two adjacent TIDs that are more than 2^31 blocks apart.
According to the comment, we would store that in 6 bytes, with no
continuation bit on the 6th byte, but in reality, the code encodes it
using 7 bytes, with a continuation bit on the 6th byte as normal.
The decoding routine also handled these 7-byte integers correctly, except
for an overflow check that assumed that one integer needs at most 6 bytes.
Fix the overflow check, and fix the comment to match what the code
actually does. Also fix the comment that claimed that there are 17 unused
bits in the 64-bit representation of an item pointer. In reality, there
are 64-32-11=21.
Fitting any item pointer into max 6 bytes was an important property when
this was written, because in the old pre-9.4 format, item pointers were
stored as plain arrays, with 6 bytes for every item pointer. The maximum
of 6 bytes per integer in the new format guaranteed that we could convert
any page from the old format to the new format after upgrade, so that the
new format was never larger than the old format. But we hardly need to
worry about that anymore, and running into that problem during upgrade,
where an item pointer is expanded from 6 to 7 bytes such that the data
doesn't fit on a page anymore, is implausible in practice anyway.
Backpatch to all supported versions.
This also includes a little test module to test these large distances
between item pointers, without requiring a 16 TB table. It is not
backpatched, I'm including it more for the benefit of future development
of new posting list formats.
Discussion: https://www.postgresql.org/message-id/33bfc20a-5c86-f50c-f5a5-58e9925d05ff%40iki.fi
Reviewed-by: Masahiko Sawada, Alexander Korotkov
In this case, the transfer uses a libpq connection, which is subject to
the timeout parameters set at system level, and this can make the rewind
operation suddenly canceled which is not good for automation. One
workaround to such issues would be to use PGOPTIONS to enforce the
wanted timeout parameters, but that's annoying, and for example pg_dump,
which can run potentially long-running queries disables all types of
timeouts.
lock_timeout and statement_timeout are the ones which can cause problems
now. Note that pg_rewind does not use transactions, so disabling
idle_in_transaction_session_timeout is optional, but it feels safer to
do so for the future.
This is back-patched down to 9.5. idle_in_transaction_session_timeout
is only present since 9.6.
Author: Alexander Kukushkin
Discussion: https://postgr.es/m/CAFh8B=krcVXksxiwVQh1SoY+ziJ-JC=6FcuoBL3yce_40Es5_g@mail.gmail.com
Backpatch-through: 9.5
Section 4.2.7 says that unless otherwise specified, built-in
aggregates ignore rows in which any input is null. This is
not true of the JSON aggregates, but it wasn't documented.
Fix that.
Of the other entries in table 9.55, some were explicit about
ignoring nulls, and some weren't; for consistency and
self-contained-ness, make them all say it explicitly.
Per bug #15884 from Tim Möhlmann. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/15884-c32d848f787fcae3@postgresql.org
An empty file name or subdirectory name leads join_path_components() to
just produce the parent directory name, which leads to weird failures or
recursive inclusions. Let's throw a specific error for that. It takes
only slightly more code to detect all-blank names, so do so.
Also, detect direct recursion, ie a file calling itself. As coded
this will also detect recursion via "include_dir '.'", which is
perhaps more likely than explicitly including the file itself.
Detecting indirect recursion would require API changes for guc-file.l
functions, which seems not worth it since extensions might call them.
The nesting depth limit will catch such cases eventually, just not
with such an on-point error message.
In passing, adjust the example usages in postgresql.conf.sample
to perhaps eliminate the problem at the source: there's no reason
for the examples to suggest that an empty value is valid.
Per a trouble report from Brent Bates. Back-patch to 9.5; the
issue is old, but the code in 9.4 is enough different that the
patch doesn't apply easily, and it doesn't seem worth the trouble
to fix there.
Ian Barwick and Tom Lane
Discussion: https://postgr.es/m/8c8bcbca-3bd9-dc6e-8986-04a5abdef142@2ndquadrant.com
FD_SETSIZE needs to be declared before winsock2.h, or it is possible to
run into buffer overflow issues when using --jobs. This is similar to
pgbench's solution done in a23c641.
This has been introduced by 71d84ef, and older versions have been using
the default value of FD_SETSIZE, defined at 64. While on it, add a
missing newline to the previously-added error message.
Per buildfarm member jacana, but this impacts all Windows animals
running the TAP tests. I have reproduced the failure locally to check
the patch.
Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/20190826054000.GE7005@paquier.xyz
Backpatch-through: 9.5
On msys2, 'uname -s' reports a string starting MSYS instead on MINGW
as happens on msys1. Treat these both the same way. This reverts
608a710195a4b in favor of a more general solution.
Backpatch to all live branches.
When trying to use a high number of jobs, vacuumdb has only checked for
a maximum number of jobs used, causing confusing failures when running
out of file descriptors when the jobs open connections to Postgres.
This commit changes the error handling so as we do not check anymore for
a maximum number of allowed jobs when parsing the option value with
FD_SETSIZE, but check instead if a file descriptor is within the
supported range when opening the connections for the jobs so as this is
detected at the earliest time possible.
Also, improve the error message to give a hint about the number of jobs
recommended, using a wording given by the reviewers of the patch.
Reported-by: Andres Freund
Author: Michael Paquier
Reviewed-by: Andres Freund, Álvaro Herrera, Tom Lane
Discussion: https://postgr.es/m/20190818001858.ho3ev4z57fqhs7a5@alap3.anarazel.de
Backpatch-through: 9.5
POSIX permits getopt() to advance optind beyond argc when the last
argv entry is an option that requires an argument and hasn't got one.
It seems that no major platforms actually do that, but musl does,
so that something like "psql -f" would crash with that libc.
Add a check that optind is in range before trying to look at the
possibly-bogus option.
Report and fix by Quentin Rameau. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/20190825100617.GA6087@fifth.space
In early development patches, "replication origins" were called "identifiers";
almost everything was renamed, but these references to the old terminology
went unnoticed.
Reported-by: Craig Ringer
If a table inherits from multiple unrelated parents, we must disallow
changing the type of a column inherited from multiple such parents, else
it would be out of step with the other parents. However, it's possible
for the column to ultimately be inherited from just one common ancestor,
in which case a change starting from that ancestor should still be
allowed. (I would not be excited about preserving that option, were
it not that we have regression test cases exercising it already ...)
It's slightly annoying that this patch looks different from the logic
with the same end goal in renameatt(), and more annoying that it
requires an extra syscache lookup to make the test. However, the
recursion logic is quite different in the two functions, and a
back-patched bug fix is no place to be trying to unify them.
Per report from Manuel Rigger. Back-patch to 9.5. The bug exists in
9.4 too (and doubtless much further back); but the way the recursion
is done in 9.4 is a good bit different, so that substantial refactoring
would be needed to fix it in 9.4. I'm disinclined to do that, or risk
introducing new bugs, for a bug that has escaped notice for this long.
Discussion: https://postgr.es/m/CA+u7OA4qogDv9rz1HAb-ADxttXYPqQdUdPY_yd4kCzywNxRQXA@mail.gmail.com
This is a variant of the problem fixed in commit 25b692568, which
unfortunately we failed to detect at the time. If an update trigger
returns the "old" tuple, as it's entitled to do, then a subsequent
iteration of the loop in ExecBRUpdateTriggers would have "oldtuple"
equal to "trigtuple" and would fail to notice that it shouldn't
free that.
In addition to fixing the code, extend the test case added by
25b692568 so that it covers multiple-trigger-iterations cases.
This problem does not manifest in v12/HEAD, as a result of the
relevant code having been largely rewritten for slotification.
However, include the test case into v12/HEAD anyway, since this
is clearly an area that someone could break again in future.
Per report from Piotr Gabriel Kosinski. Back-patch into all
supported branches, since the bug seems quite old.
Diagnosis and code fix by Thomas Munro, test case by me.
Discussion: https://postgr.es/m/CAFMLSdP0rd7LqC3j-H6Fh51FYSt5A10DDh-3=W4PPc4LLUQ8YQ@mail.gmail.com
ALTER SYSTEM itself normally won't make duplicate entries (although
up till this patch, it was possible to confuse it by writing case
variants of a GUC's name). However, if some external tool has appended
entries to the file, that could result in duplicate entries for a single
GUC name. In such a situation, ALTER SYSTEM did exactly the wrong thing,
because it replaced or removed only the first matching entry, leaving
the later one(s) still there and hence still determining the active value.
This patch fixes that by making ALTER SYSTEM sweep through the file and
remove all matching entries, then (if not ALTER SYSTEM RESET) append the
new setting to the end. This means entries will be in order of last
setting rather than first setting, but that shouldn't hurt anything.
Also, make the comparisons case-insensitive so that the right things
happen if you do, say, ALTER SYSTEM SET "TimeZone" = 'whatever'.
This has been broken since ALTER SYSTEM was invented, so back-patch
to all supported branches.
Ian Barwick, with minor mods by me
Discussion: https://postgr.es/m/aed6cc9f-98f3-2693-ac81-52bb0052307e@2ndquadrant.com
Commit 07b39083c inserted an unconditional reference to pg_opfamily,
which of course fails on servers predating that catalog. Fortunately,
the case it's trying to solve can't occur on such old servers (AFAIK).
Hence, just skip the additional code when the source predates 8.3.
Per bug #15955 from sly. Back-patch to all supported branches,
like the previous patch.
Discussion: https://postgr.es/m/15955-1daa2e676e903d87@postgresql.org
With some newer gcc versions (8 and 9) you get a -Wformat-overflow
warning here. In PG11 and later this was already fixed. Since it's
trivial, backport it to get the older branches building without
warnings.
VACUUM's reference page had this text, but ANALYZE's didn't. That's
a clear oversight given that section 5.7 explicitly delegates the
responsibility to define permissions requirements to the individual
commands' man pages.
Per gripe from Isaac Morland. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAMsGm5fp3oBUs-2iRfii0iEO=fZuJALVyM2zJLhNTjG34gpAVQ@mail.gmail.com
In serializable mode, heap_hot_search_buffer() incorrectly acquired a
predicate lock on the root tuple, not the returned tuple that satisfied
the visibility checks. As explained in README-SSI, the predicate lock does
not need to be copied or extended to other tuple versions, but for that to
work, the correct, visible, tuple version must be locked in the first
place.
The original SSI commit had this bug in it, but it was fixed back in 2013,
in commit 81fbbfe335. But unfortunately, it was reintroduced a few months
later in commit b89e151054. Wising up from that, add a regression test
to cover this, so that it doesn't get reintroduced again. Also, move the
code that sets 't_self', so that it happens at the same time that the
other HeapTuple fields are set, to make it more clear that all the code in
the loop operate on the "current" tuple in the chain, not the root tuple.
Bug spotted by Andres Freund, analysis and original fix by Thomas Munro,
test case and some additional changes to the fix by Heikki Linnakangas.
Backpatch to all supported versions (9.4).
Discussion: https://www.postgresql.org/message-id/20190731210630.nqhszuktygwftjty%40alap3.anarazel.de
When parsing a timetz string with a dynamic timezone abbreviation or a
timezone not specified, it was possible to generate incorrect timestamps
based on a date which uses some non-initialized variables if the input
string did not specify fully a date to parse. This is already checked
when a full timezone spec is included in the input string, but the two
other cases mentioned above missed the same checks.
This gets fixed by generating an error as this input is invalid, or in
short when a date is not fully specified.
Valgrind was complaining about this problem.
Bug: #15910
Author: Alexander Lakhin
Discussion: https://postgr.es/m/15910-2eba5106b9aa0c61@postgresql.org
Backpatch-through: 9.4
contrib/intarray considers "arraycol <@ constant-array" to be indexable,
but its GiST opclass code fails to reliably find index entries for empty
array values (which of course should trivially match such queries).
This is because the test condition to see whether we should descend
through a non-leaf node is wrong.
Unfortunately, empty array entries could be anywhere in the index,
as these index opclasses are currently designed. So there's no way
to fix this except by lobotomizing <@ indexscans to scan the whole
index ... which is what this patch does. That's pretty unfortunate:
the performance is now actually worse than a seqscan, in most cases.
We'd be better off to remove <@ from the GiST opclasses entirely,
and perhaps a future non-back-patchable patch will do so.
In the meantime, applications whose performance is adversely impacted
have a couple of options. They could switch to a GIN index, which
doesn't have this bug, or they could replace "arraycol <@ constant-array"
with "arraycol <@ constant-array AND arraycol && constant-array".
That will provide about the same performance as before, and it will find
all non-empty subsets of the given constant-array, which is all that
could reliably be expected of the query before.
While at it, add some more regression test cases to improve code
coverage of contrib/intarray.
In passing, adjust resize_intArrayType so that when it's returning an
empty array, it uses construct_empty_array for that rather than
cowboy hacking on the input array. While the hack produces an array
that looks valid for most purposes, it isn't bitwise equal to empty
arrays produced by other code paths, which could have subtle odd
effects. I don't think this code path is performance-critical
enough to justify such shortcuts. (Back-patch this part only as far
as v11; before commit 01783ac36 we were not careful about this in
other intarray code paths either.)
Back-patch the <@ fixes to all supported versions, since this was
broken from day one.
Patch by me; thanks to Alexander Korotkov for review.
Discussion: https://postgr.es/m/458.1565114141@sss.pgh.pa.us
