Previously socket errors such as invalid socket or socket wait method failures
during benchmark caused pgbench to exit with status 0. Instead, errors during
the run should result in exit status 2.
Back-patch to v12 where pgbench started reporting exit status.
Original complaint and patch by Hayato Kuroda.
Author: Yugo Nagata, Fabien COELHO
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/TYCPR01MB5870057375ACA8A73099C649F5349@TYCPR01MB5870.jpnprd01.prod.outlook.com
The failure of socket wait method like "select()" doesn't terminate pgbench.
So the log level of error message when that failure happens should be ERROR.
But previously FATAL was used in that case.
Back-patch to v13 where pgbench started using common logging API.
Author: Yugo Nagata, Fabien COELHO
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/20210617005934.8bd37bf72efd5f1b38e6f482@sraoss.co.jp
The code inconsistently used "statistic object" or "statistics" where
the correct term, as discussed, is actually "statistics object". This
improves the state of the code to be more consistent.
While on it, fix an incorrect error message introduced in a4d75c8. This
error should never happen, as the code states, but it would be
misleading.
Author: Justin Pryzby
Reviewed-by: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/20210924215827.GS831@telsasoft.com
Backpatch-through: 14
A forked logging collector in EXEC_BACKEND builds passes down file
descriptors (or HANDLEs in WIN32) through a command for files to be
reopened (for stderr and csvlog). Some of its logic was duplicated, and
this commit refactors the code with some wrapper routines for file
reopening after forking and fd grabbing when building the command for
the fork.
While on it, this simplifies a use of "long" in the code, introduced by
ab0ba6e to take care of a warning related to MinGW-W64 when mapping a
intptr_t to a printed value. "long" is 32-bit long on Windows, and
interoperability of Win32 and Win64 ensures that handles are always
32-bit significant, so we can just use "int" for the same result. This
also makes the new routines more symmetric.
This change makes easier the introduction of new log destinations in the
logging collector, and this is not the only piece of refactoring
planned. I have tested this change with EXEC_BACKEND on linux, macos,
and of course MSVC (both Win32 and Win64), but not MinGW so the
buildfarm may have something to say here.
Author: Sehrope Sarkuni, Michael Paquier
Discussion: https://postgr.es/m/CAH7T-aqswBM6JWe4pDehi1uOiufqe06DJWaU5=X7dDLyqUExHg@mail.gmail.com
Sequences were left out of the list of relation kinds that
verify_heapam knew how to check, though it is fairly trivial to allow
them. Doing that, and while at it, updating pg_amcheck to include
sequences in relations matched by table and relation patterns.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/81ad4757-92c1-4aa3-7bee-f609544837e3%40enterprisedb.com
Several mistakes have piled in the code comments over the time,
including incorrect grammar, function names and simple typos. This
commit takes care of a portion of these.
No backpatch is done as this is only cosmetic.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20210924215827.GS831@telsasoft.com
Discussing the low level issue of nbtree VACUUM and recovery conflicts
in btvacuumpage() now seems inappropriate. The same issue is discussed
in nbtxlog.h, as well as in a comment block above _bt_delitems_vacuum().
The comment block made more sense when it was part of a broader
discussion of nbtree VACUUM "pin scans". These were removed by commit
9f83468b.
Splitting the time field into days and microseconds is pretty
useless when we're just going to recombine those values.
It's unclear if anyone will notice the speedup in real-world
cases, but a cycle shaved is a cycle earned.
Discussion: https://postgr.es/m/2629129.1632675713@sss.pgh.pa.us
_bt_delitems_delete() is no longer the high-level entry point used by
index tuple deletion driven by index tuples whose LP_DEAD bits are set
(now called "simple index tuple deletion"). It became a lower level
routine that's only called by _bt_delitems_delete_check() following
commit d168b66682.
Remove obsolete reference to lazy_vacuum()'s onecall argument. The
function argument was removed by commit 3499df0dee.
Also remove adjoining comment block that introduces the wraparound
failsafe concept. Talking about the failsafe here no longer makes
sense, since lazy_vacuum() (and related functions) are no longer the
only place where the failsafe might be triggered. This has been the
case since commit c242baa4a8 taught VACUUM to consider triggering the
failsafe mechanism during its initial heap scan.
Point out that index tuple deletion generally needs a latestRemovedXid
value for the deletion operation's WAL record. This is bound to be the
most expensive part of the whole deletion operation now that it takes
place up front, during original execution.
This was arguably an oversight in commit 558a9165e0, which moved the
work required to generate these values from index deletion REDO routines
to original execution of index deletion operations.
unicode_east_asian_fw_table.h should not be compiled standalone, similarly
to unicode_combining_table.h, but cpluspluscheck did not get the memo.
Oversight in bab982161.
Per report from Tom Lane
That allows to include just visibilitymapdefs.h from file.c, and in turn,
remove include of postgres.h from relcache.h.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/20210913232614.czafiubr435l6egi%40alap3.anarazel.de
Author: Alexander Korotkov
Reviewed-by: Andres Freund, Tom Lane, Alvaro Herrera
Backpatch-through: 13
Calculating degree of a functional dependency may allocate a lot of
memory - we have released mot of the explicitly allocated memory, but
e.g. detoasted varlena values were left behind. That may be an issue,
because we consider a lot of dependencies (all combinations), and the
detoasting may happen for each one again.
Fixed by calling dependency_degree() in a dedicated context, and
resetting it after each call. We only need the calculated dependency
degree, so we don't need to copy anything.
Backpatch to PostgreSQL 10, where extended statistics were introduced.
Backpatch-through: 10
Discussion: https://www.postgresql.org/message-id/20210915200928.GP831%40telsasoft.com
Until now, all extended statistics on a given relation were built in the
same memory context, without resetting. Some of the memory was released
explicitly, but not all of it - for example memory allocated while
detoasting values is hard to free. This is how it worked since extended
statistics were introduced in PostgreSQL 10, but adding support for
extended stats on expressions made the issue somewhat worse as it
increases the number of statistics to build.
Fixed by adding a memory context which gets reset after building each
statistics object (all the statistics kinds included in it). Resetting
it after building each statistics kind would be even better, but it
would require more invasive changes and copying of results, making it
harder to backpatch.
Backpatch to PostgreSQL 10, where extended statistics were introduced.
Author: Justin Pryzby
Reported-by: Justin Pryzby
Reviewed-by: Tomas Vondra
Backpatch-through: 10
Discussion: https://www.postgresql.org/message-id/20210915200928.GP831%40telsasoft.com
Checking that an offset number isn't past the end of a heap page's line
pointer array was just a defensive sanity check for HOT-chain traversal
code before commit 3c3b8a4b. It's etrictly necessary now, though. Add
comments that reference the issue to code in heapam that needs to get it
right.
Per suggestion from Alexander Lakhin.
Discussion: https://postgr.es/m/f76a292c-9170-1aef-91a0-59d9443b99a3@gmail.com
Updates/Deletes on a partition were allowed even without replica identity
after the parent table was added to a publication. This would later lead
to an error on subscribers. The reason was that we were not invalidating
the partition's relcache and the publication information for partitions
was not getting rebuilt. Similarly, we were not invalidating the
partitions' relcache after dropping a partitioned table from a publication
which will prohibit Updates/Deletes on its partition without replica
identity even without any publication.
Reported-by: Haiying Tang
Author: Hou Zhijie and Vignesh C
Reviewed-by: Vignesh C and Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/OS0PR01MB6113D77F583C922F1CEAA1C3FBD29@OS0PR01MB6113.jpnprd01.prod.outlook.com
It is not appropriate for deduplication to apply single value strategy
when triggered by a bottom-up index deletion pass. This wastes cycles
because later bottom-up deletion passes will overinterpret older
duplicate tuples that deduplication actually just skipped over "by
design". It also makes bottom-up deletion much less effective for low
cardinality indexes that happen to cross a meaningless "index has single
key value per leaf page" threshold.
To fix, slightly narrow the conditions under which deduplication's
single value strategy is considered. We already avoided the strategy
for a unique index, since our high level goal must just be to buy time
for VACUUM to run (not to buy space). We'll now also avoid it when we
just had a bottom-up pass that reported failure. The two cases share
the same high level goal, and already overlapped significantly, so this
approach is quite natural.
Oversight in commit d168b666, which added bottom-up index deletion.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WznaOvM+Gyj-JQ0X=JxoMDxctDTYjiEuETdAGbF5EUc3MA@mail.gmail.com
Backpatch: 14-, where bottom-up deletion was introduced.
This addresses two issues with the tests added in 0c39c292 for runtime
GUCs:
- Re-enable the test on Msys. The test could fail because of \r\n
generated by Msys perl. 0d91c52a has taken care of this issue.
- Allow the test to run in the context of a privileged account. CIs
running under privileged accounts would fail on permission failures, as
reported by Andres Freund. This issue is fixed by wrapping the postgres
command within pg_ctl as the latter will take care of any permissions
needed. The test checking a failure of postgres -C for a runtime
parameter with an instance running is removed, as pg_ctl produces an
unstable error code (no need for a CI to reproduce that).
Discussion: https://postgr.es/m/20210921032040.lyl4lcax37aedx2x@alap3.anarazel.de
Contrary to the output of native perl, Msys perl generates outputs with
CRLFs characters. There are already places in the TAP code where CRLFs
(\r\n) are automatically converted to LF (\n) on Msys, but we missed a
couple of places when running commands and using their output for
comparison, that would lead to failures.
This problem has been found thanks to the test added in 5adb067 using
TestLib::command_checks_all(), but after a closer look more code paths
were missing a filter.
This is backpatched all the way down to prevent any surprises if a new
test is introduced in stable branches.
Reviewed-by: Andrew Dunstan, Álvaro Herrera
Discussion: https://postgr.es/m/1252480.1631829409@sss.pgh.pa.us
Backpatch-through: 9.6
Before commit 84f5c2908, a STABLE function in a plpgsql CALL
statement's argument list would see an up-to-date snapshot,
because exec_stmt_call would push a new snapshot. I got rid of
that because the possibility of the snapshot disappearing within
COMMIT made it too hard to manage a snapshot across the CALL
statement. That's fine so far as the procedure itself goes,
but I forgot to think about the possibility of STABLE functions
within the CALL argument list. As things now stand, those'll
be executed with the Portal's snapshot as ActiveSnapshot,
keeping them from seeing updates more recent than Portal startup.
(VOLATILE functions don't have a problem because they take their
own snapshots; which indeed is also why the procedure itself
doesn't have a problem. There are no STABLE procedures.)
We can fix this by pushing a new snapshot transiently within
ExecuteCallStmt itself. Popping the snapshot before we get
into the procedure proper eliminates the management problem.
The possibly-useless extra snapshot-grab is slightly annoying,
but it's no worse than what happened before 84f5c2908.
Per bug #17199 from Alexander Nawratil. Back-patch to v11,
like the previous patch.
Discussion: https://postgr.es/m/17199-1ab2561f0d94af92@postgresql.org
I noticed that commit 0bead9af48 left this flag undocumented in
XLogSetRecordFlags, which led me to discover that the flag doesn't
actually do what the one comment on it said it does. Improve the
situation by adding some more comments.
Backpatch to 14, where the aforementioned commit appears.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/202109212119.c3nhfp64t2ql@alvherre.pgsql
This runtime-computed GUC shows the number of huge pages required
for the server's main shared memory area, taking advantage of the
work done in 0c39c29 and 0bd305e. This is useful for users to estimate
the amount of huge pages required for a server as it becomes possible to
do an estimation without having to start the server and potentially
allocate a large chunk of shared memory.
The number of huge pages is calculated based on the existing GUC
huge_page_size if set, or by using the system's default by looking at
/proc/meminfo on Linux. There is nothing new here as this commit reuses
the existing calculation methods, and just exposes this information
directly to the user. The routine calculating the huge page size is
refactored to limit the number of files with platform-specific flags.
This new GUC's name was the most popular choice based on the discussion
done. This is only supported on Linux.
I have taken the time to test the change on Linux, Windows and MacOS,
though for the last two ones large pages are not supported. The first
one calculates correctly the number of pages depending on the existing
GUC huge_page_size or the system's default.
Thanks to Andres Freund, Robert Haas, Kyotaro Horiguchi, Tom Lane,
Justin Pryzby (and anybody forgotten here) for the discussion.
Author: Nathan Bossart
Discussion: https://postgr.es/m/F2772387-CE0F-46BF-B5F1-CC55516EB885@amazon.com
A broken HOT chain is not an unexpected condition, even when the offset
number points past the end of the page's line pointer array.
heap_prune_chain() does not (and never has) treated this condition as
unexpected, so derivative code in heap_index_delete_tuples() shouldn't
do so either.
Oversight in commit 4228817449.
The assertion can probably only fail on Postgres 14 and master. Earlier
releases don't have commit 3c3b8a4b, which taught VACUUM to truncate the
line pointer array of heap pages. Backpatch all the same, just to be
consistent.
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/17197-9438f31f46705182@postgresql.org
Backpatch: 12-, just like commit 4228817449.
The upcoming shared memory stats patch drops stats for dropped objects in a
transactional manner, rather than removing them later as part of vacuum. This
means that stats for DROP inside a transaction needs to handle aborted
(sub-)transactions similar to TRUNCATE: The stats up to the DROP should be
restored.
Rename the existing infrastructure in preparation.
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210405092914.mmxqe7j56lsjfsej@alap3.anarazel.de
An upcoming patch will add additional work to these functions. To avoid the
functions getting too complicated / doing too many things at once, split out
sub-tasks into their own functions.
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210405092914.mmxqe7j56lsjfsej@alap3.anarazel.de
Since introduction of extended statistics, we've disallowed references
to system columns. So for example
CREATE STATISTICS s ON ctid FROM t;
would fail. But with extended statistics on expressions, it was possible
to work around this limitation quite easily
CREATE STATISTICS s ON (ctid::text) FROM t;
This is an oversight in a4d75c86bf, fixed by adding a simple check.
Backpatch to PostgreSQL 14, where support for extended statistics on
expressions was introduced.
Backpatch-through: 14
Discussion: https://postgr.es/m/20210816013255.GS10479%40telsasoft.com
It was harder than necessary to understand PostgresMain() because the code for
a normal backend was interspersed with single-user mode specific code. Split
most of the single-user mode code into its own function
PostgresSingleUserMain(), that does all the necessary setup for single-user
mode, and then hands off after that to PostgresMain().
There still is some single-user mode code in InitPostgres(), and it'd likely
be worth moving at least some of it out. But that's for later.
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210802164124.ufo5buo4apl6yuvs@alap3.anarazel.de
The following things are improved:
- Fetch the system identifier from the source server before any
WAL streaming loop. This triggers extra checks to make sure that
pg_receivewal is still connected to a server with the same system ID
with a correct timeline.
- Switch umask() (for file creation mode mask) and RetrieveWalSegSize()
(to fetch the size of WAL segments) a bit later before the initial
stream attempt. If the connection was done with a database,
pg_receivewal would fail but those commands were still executed, which
was a waste. The slot creation and drop are now done before retrieving
the segment size.
Author: Bharath Rupireddy
Reviewed-by: Ronan Dunklau, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACX00YYeyBfoi55Cy=NrP-FcfMgiYYx1qRUEib3yjCVoaA@mail.gmail.com
Commit 55dc86eca changed pull_varnos to use (if possible) the associated
ph_eval_at for a PlaceHolderVar. I missed a fine point though: we might
be looking at a PHV in the quals or tlist of a child appendrel, in which
case we need to compute a ph_eval_at value that's been translated in the
same way that the PHV itself has been (cf. adjust_appendrel_attrs).
Fortunately, enough info is available in the PlaceHolderInfo to make
such translation possible without additional outside data, so we don't
need another round of uglification of planner APIs. This is a little
bit complicated, but since it's a hard-to-hit corner case, I'm not much
worried about adding cycles here.
Per report from Jaime Casanova. Back-patch to v12, like the previous
commit.
Discussion: https://postgr.es/m/20210915230959.GB17635@ahch-to
A WAL segment closed during a WAL stream for pg_receivewal would
generate incorrect error messages depending on the context, as the file
name used when referring to a WAL segment ignored partial files or the
compression method used. In such cases, the error message generated
(failure on close, seek or rename) would not match a physical file
name. The same code paths are used by pg_basebackup, but it uses no
partial suffix so it is not impacted.
7fbe0c8 has introduced in walmethods.c a callback to get the exact
physical file name used for a given context, this commit makes use of it
to improve those error messages. This could be extended to more code
paths of pg_basebackup/ in the future, if necessary.
Extracted from a larger patch by the same author.
Author: Georgios Kokolatos
Discussion: https://postgr.es/m/ZCm1J5vfyQ2E6dYvXz8si39HQ2gwxSZ3IpYaVgYa3lUwY88SLapx9EEnOf5uEwrddhx2twG7zYKjVeuP5MwZXCNPybtsGouDsAD1o2L_I5E=@pm.me
The output generated on Msys is incorrect because of the different way
IPC::Run processes outputs with native Perl (converts natively \r\n to
\n) and Msys perl (\r\n kept as-is), causing this test to fail.
For now, just disable the test to bring the buildfarm to a green state.
I think that the correct long-term solution would be to tweak all the
routines command_checks_* in PostgresNode.pm to handle this output like
psql does when using Msys, by discarding \r automatically before
comparing it.
Per report from jacana and fairywren. Thanks to Tom Lane for the ping.
Discussion: https://postgr.es/m/1252480.1631829409@sss.pgh.pa.us
The rewriter transformation for SEARCH BREADTH FIRST produces a
FieldSelect on a Var of type RECORD, where the Var references the
recursive union's worktable output. EXPLAIN VERBOSE failed to handle
this case, because it only expected such Vars to appear in CteScans
not WorkTableScans. Fix that, and add some test cases exercising
EXPLAIN on SEARCH and CYCLE queries.
In principle this oversight is an old bug, but it seems that the
case is unreachable without SEARCH BREADTH FIRST, because the
parser fails when attempting to create such a reference manually.
So for today I'll just patch HEAD/v14. Someday we might find that
the code portion of this patch needs to be back-patched further.
Per report from Atsushi Torikoshi.
Discussion: https://postgr.es/m/5bafa66ad529e11860339565c9e7c166@oss.nttdata.com
An upcoming patch splits single user mode into its own function. This makes
that easier. Split out for easier review / testing.
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210802164124.ufo5buo4apl6yuvs@alap3.anarazel.de
Session statistics, as introduced by 960869da08, had several shortcomings:
- an additional GetCurrentTimestamp() call that also impaired the accuracy of
the data collected
This can be avoided by passing the current timestamp we already have in
pgstat_report_stat().
- an additional statistics UDP packet sent every 500ms
This is solved by adding the new statistics to PgStat_MsgTabstat.
This is conceptually ugly, because session statistics are not
table statistics. But the struct already contains data unrelated
to tables, so there is not much damage done.
Connection and disconnection are reported in separate messages, which
reduces the number of additional messages to two messages per session and a
slight increase in PgStat_MsgTabstat size (but the same number of table
stats fit).
- Session time computation could overflow on systems where long is 32 bit.
Reported-By: Andres Freund <andres@anarazel.de>
Author: Andres Freund <andres@anarazel.de>
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/20210801205501.nyxzxoelqoo4x2qc%40alap3.anarazel.de
Backpatch: 14-, where the feature was introduced.
ProcArrayGroupClearXid function has a parameter named "proc",
but the same name was used for its local variables. This commit fixes
this variable shadowing, to improve code readability.
Back-patch to all supported versions, to make future back-patching
easy though this patch is classified as refactoring only.
Reported-by: Ranier Vilela
Author: Ranier Vilela, Aleksander Alekseev
https://postgr.es/m/CAEudQAqyoTZC670xWi6w-Oe2_Bk1bfu2JzXz6xRfiOUzm7xbyQ@mail.gmail.com
All size_t variables declared in procarray.c are actually int ones.
Let's use int instead of size_t for those variables. Which would
reduce Wsign-compare compiler warnings.
Back-patch to v14 where commit 941697c3c1 added size_t variables
in procarray.c, to make future back-patching easy though
this patch is classified as refactoring only.
Reported-by: Ranier Vilela
Author: Ranier Vilela, Aleksander Alekseev
https://postgr.es/m/CAEudQAqyoTZC670xWi6w-Oe2_Bk1bfu2JzXz6xRfiOUzm7xbyQ@mail.gmail.com
Until now, the -C option of postgres was handled before a small subset
of GUCs computed at runtime are initialized, leading to incorrect
results as GUC machinery would fall back to default values for such
parameters.
For example, data_checksums could report "off" for a cluster as the
control file is not loaded yet. Or wal_segment_size would show a
segment size at 16MB even if initdb --wal-segsize used something else.
Worse, the command would fail to properly report the recently-introduced
shared_memory, that requires to load shared_preload_libraries as these
could ask for a chunk of shared memory.
Support for runtime GUCs comes with a limitation, as the operation is
now allowed on a running server. One notable reason for this is that
_PG_init() functions of loadable libraries are called before all
runtime-computed GUCs are initialized, and this is not guaranteed to be
safe to do on running servers. For the case of shared_memory_size,
where we want to know how much memory would be used without allocating
it, this limitation is fine. Another case where this will help is for
huge pages, with the introduction of a different GUC to evaluate the
amount of huge pages required for a server before starting it, without
having to allocate large chunks of memory.
This feature is controlled with a new GUC flag, and four parameters are
classified as runtime-computed as of this change:
- data_checksums
- shared_memory_size
- data_directory_mode
- wal_segment_size
Some TAP tests are added to provide some coverage here, using
data_checksums in the tests of pg_checksums.
Per discussion with Andres Freund, Justin Pryzby, Magnus Hagander and
more.
Author: Nathan Bossart
Discussion: https://postgr.es/m/F2772387-CE0F-46BF-B5F1-CC55516EB885@amazon.com
An upcoming patch splits single user mode handling out of PostgresMain(). The
startup time only needs to be determined in single user mode. Currently the
initialization happens late, which makes the split a bit harder. As postmaster
determines the time earlier it makes sense to move the time for single user
mode to a roughly similar point in time.
Reviewd-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210802164124.ufo5buo4apl6yuvs@alap3.anarazel.de
Up to now the size of a query's rangetable has been limited by the
constants INNER_VAR et al, which mustn't be equal to any real
rangetable index. 65000 doubtless seemed like enough for anybody,
and it still is orders of magnitude larger than the number of joins
we can realistically handle. However, we need a rangetable entry
for each child partition that is (or might be) processed by a query.
Queries with a few thousand partitions are getting more realistic,
so that the day when that limit becomes a problem is in sight,
even if it's not here yet. Hence, let's raise the limit.
Rather than just increase the values of INNER_VAR et al, this patch
adopts the approach of making them small negative values, so that
rangetables could theoretically become as long as INT_MAX.
The bulk of the patch is concerned with changing Var.varno and some
related variables from "Index" (unsigned int) to plain "int". This
is basically cosmetic, with little actual effect other than to help
debuggers print their values nicely. As such, I've only bothered
with changing places that could actually see INNER_VAR et al, which
the parser and most of the planner don't. We do have to be careful
in places that are performing less/greater comparisons on varnos,
but there are very few such places, other than the IS_SPECIAL_VARNO
macro itself.
A notable side effect of this patch is that while it used to be
possible to add INNER_VAR et al to a Bitmapset, that will now
draw an error. I don't see any likelihood that it wouldn't be a
bug to include these fake varnos in a bitmapset of real varnos,
so I think this is all to the good.
Although this touches outfuncs/readfuncs, I don't think a catversion
bump is required, since stored rules would never contain Vars
with these fake varnos.
Andrey Lepikhov and Tom Lane, after a suggestion by Peter Eisentraut
Discussion: https://postgr.es/m/43c7f2f5-1e27-27aa-8c65-c91859d15190@postgrespro.ru
Fujii Masao
Michael Paquier
Peter Eisentraut
Magnus Hagander
Peter Geoghegan
Thomas Munro
Tom Lane
John Naylor
Alexander Korotkov
Tomas Vondra
Amit Kapila
Alvaro Herrera
Andres Freund