rescanLatestTimeLine() contains a guard against switching to
a timeline that forked off from the current one prior to the
current recovery point, but that guard does not work if the
timeline switch occurs before the first WAL recod (which must
be the checkpoint record) is read. Without this patch, an
improper timeline switch is therefore possible in such cases.
This happens because rescanLatestTimeLine() relies on the global
variable EndRecPtr to understand the current position of WAL
replay. However, EndRecPtr at this point in the code contains
the endpoint of the last-replayed record, not the startpoint or
endpoint of the record being replayed now. Thus, before any
records have been replayed, it's zero, which causes the sanity
check to always pass.
To fix, pass down the correct timeline explicitly. The
EndRecPtr value we want is the one from the xlogreader, which
will be the starting position of the record we're about to
try to read, rather than the global variable, which is the
ending position of the last record we successfully read.
They're usually the same, but not in the corner case described
here.
No back-patch, because in v14 and earlier branhes, we were using
the wrong TLI here as well as the wrong LSN. In master, that was
fixed by commit 4a92a1c3d1, but
that and it's prerequisite patches are too invasive to
back-patch for such a minor issue.
Patch by me, reviewed by Amul Sul.
Discussion: http://postgr.es/m/CA+Tgmoao96EuNeSPd+hspRKcsCddu=b1h-QNRuKfY8VmfNQdfg@mail.gmail.com
If an error occurs when writing the LZ4 file header, LZ4F_compressEnd()
was called in the error code path of write(), followed by
LZ4F_freeCompressionContext() to finish the cleanup. The code as-is was
not broken, but the LZ4F_compressEnd() proves to not be necessary as
there are no contents to flush at this stage, so remove it.
Per gripe from Jeevan Ladhe and Robert Haas.
Discussion: https://postgr.es/m/CAOgcT0PE33wbD7giAT1OSkNJt=p-vu8huq++qh=ny9O=SCP5aA@mail.gmail.com
It's possible that a subplan below a Memoize node contains a parameter
from above the Memoize node. If this parameter changes then cache entries
may become out-dated due to the new parameter value.
Previously Memoize was mistakenly not aware of this. We fix this here by
flushing the cache whenever a parameter that's not part of the cache
key changes.
Bug: #17213
Reported by: Elvis Pranskevichus
Author: David Rowley
Discussion: https://postgr.es/m/17213-988ed34b225a2862@postgresql.org
Backpatch-through: 14, where Memoize was added
Documentation and any code paths related to VS are updated to keep the
whole consistent. Similarly to 2017 and 2019, the version of VS and the
version of nmake that we use to determine which code paths to use for
the build are still inconsistent in their own way.
Backpatch down to 10, so as buildfarm members are able to use this new
version of Visual Studio on all the stable branches supported.
Author: Hans Buschmann
Discussion: https://postgr.es/m/1633101364685.39218@nidsa.net
Backpatch-through: 10
Same macro names for SnapBuildOnDiskNotChecksummedSize and
SnapBuildOnDiskChecksummedSize are being used in slot.c and snapbuild.c.
This patch renames them, in slot.c, to
ReplicationSlotOnDiskNotChecksummedSize and
ReplicationSlotOnDiskChecksummedSize similar to the other macros. This
makes all macro names look consistent in slot.c.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACVZo-piDGzBOJRY4ob=_goFR6t9DhZMDMjJWN7LQs34Aw@mail.gmail.com
It's possible that a subplan below a Memoize node contains a parameter
from above the Memoize node. If this parameter changes then cache entries
may become out-dated due to the new parameter value.
Previously Memoize was mistakenly not aware of this. We fix this here by
flushing the cache whenever a parameter that's not part of the cache
key changes.
Bug: #17213
Reported by: Elvis Pranskevichus
Author: David Rowley
Discussion: https://postgr.es/m/17213-988ed34b225a2862@postgresql.org
Backpatch-through: 14, where Memoize was added
Memoize would always use the hash equality operator for the cache key
types to determine if the current set of parameters were the same as some
previously cached set. Certain types such as floating points where -0.0
and +0.0 differ in their binary representation but are classed as equal by
the hash equality operator may cause problems as unless the join uses the
same operator it's possible that whichever join operator is being used
would be able to distinguish the two values. In which case we may
accidentally return in the incorrect rows out of the cache.
To fix this here we add a binary mode to Memoize to allow it to the
current set of parameters to previously cached values by comparing
bit-by-bit rather than logically using the hash equality operator. This
binary mode is always used for LATERAL joins and it's used for normal
joins when any of the join operators are not hashable.
Reported-by: Tom Lane
Author: David Rowley
Discussion: https://postgr.es/m/3004308.1632952496@sss.pgh.pa.us
Backpatch-through: 14, where Memoize was added
This commit adds a set of functions able to look at the contents of
various paths related to replication slots:
- pg_ls_logicalsnapdir, for pg_logical/snapshots/
- pg_ls_logicalmapdir, for pg_logical/mappings/
- pg_ls_replslotdir, for pg_replslot/<slot_name>/
These are intended to be used by monitoring tools. Unlike pg_ls_dir(),
execution permission can be granted to non-superusers. Roles members of
pg_monitor gain have access to those functions.
Bump catalog version.
Author: Bharath Rupireddy
Reviewed-by: Nathan Bossart, Justin Pryzby
Discussion: https://postgr.es/m/CALj2ACWsfizZjMN6bzzdxOk1ADQQeSw8HhEjhmVXn_Pu+7VzLw@mail.gmail.com
When a stored expression depends on a user-defined cast, the backend
records the dependency as being on the cast's implementation function
--- or indeed, if there's no cast function involved but just
RelabelType or CoerceViaIO, no dependency is recorded at all. This
is problematic for pg_dump, which is at risk of dumping things in the
wrong order leading to restore failures. Given the lack of previous
reports, the risk isn't that high, but it can be demonstrated if the
cast is used in some view whose rowtype is then used as an input or
result type for some other function. (That results in the view
getting hoisted into the functions portion of the dump, ahead of
the cast.)
A logically bulletproof fix for this would require including the
cast's OID in the parsed form of the expression, whence it could be
extracted by dependency.c, and then the stored dependency would force
pg_dump to do the right thing. Such a change would be fairly invasive,
and certainly not back-patchable. Moreover, since we'd prefer that
an expression using cast syntax be equal() to one doing the same
thing by explicit function call, the cast OID field would have to
have special ignored-by-comparisons semantics, making things messy.
So, let's instead fix this by a very simple hack in pg_dump: change
the object-type priority order so that casts are initially sorted
before functions, immediately after types. This fixes the problem
in a fairly direct way for casts that have no implementation function.
For those that do, the implementation function will be hoisted to just
before the cast by the dependency sorting step, so that we still have
a valid dump order. (I'm not sure that this provides a full guarantee
of no problems; but since it's been like this for many years without
any previous reports, this is probably enough to fix it in practice.)
Per report from Дмитрий Иванов.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAPL5KHoGa3uvyKp6z6m48LwCnTsK+LRQ_mcA4uKGfqAVSEjV_A@mail.gmail.com
If a table contains a generated column that's preceded by a dropped
column, dumpTableData_insert failed to account for the dropped
column, and would emit DEFAULT placeholder(s) in the wrong column(s).
This resulted in failures at restore time. The default COPY code path
did not have this bug, likely explaining why it wasn't noticed sooner.
While we're fixing this, we can be a little smarter about the
situation: (1) avoid unnecessarily fetching the values of generated
columns, (2) omit generated columns from the output, too, if we're
using --column-inserts. While these modes aren't expected to be
as high-performance as the COPY path, we might as well be as
efficient as we can; it doesn't add much complexity.
Per report from Дмитрий Иванов.
Back-patch to v12 where generated columns came in.
Discussion: https://postgr.es/m/CAPL5KHrkBniyQt5e1rafm5DdXvbgiiqfEQEJ9GjtVzN71Jj5pA@mail.gmail.com
Normally "prove" and "perl" come from the same Perl installation,
but we support the case where they don't (mainly because the MSys
buildfarm animals need this). In that case, AX_PROG_PERL_MODULES
is completely the wrong thing to use, because it's checking what
"perl" has. Instead, make a little TAP test script including the
required modules, and run that under "prove".
We don't need ax_prog_perl_modules.m4 at all after this change,
so remove it.
Back-patch to all supported branches, for the buildfarm's benefit.
(In v10, this also back-patches the effects of commit 264eb03aa.)
Andrew Dunstan and Tom Lane, per an observation by Noah Misch
Discussion: https://postgr.es/m/E1moZHS-0002Cu-Ei@gemulon.postgresql.org
A couple of spots can benefit from an added errdetail(), which matches
what we were already doing in other places; and those that cannot
withstand errdetail() can get a more descriptive primary message.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/CALj2ACV+cX1eM03GfcA=ZMLXh5fSn1X1auJLz3yuS1duPSb9QA@mail.gmail.com
A few strings (one WARNING and some memory context names) in the
autovacuum code were written in a world where "worker" had no other
possible meaning than "autovacuum worker", but that's long time gone.
Be more specific about it.
Also, change the WARNING from elog() to ereport(), to add translability.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Nathan Bossart <bossartn@amazon.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CALj2ACX2UHp76dqdoZq92a7v4APFuV5wJQ+AUrb+2HURrKN=NQ@mail.gmail.com
This doesn't belong next to very high level discussion of the tasks that
lazy_scan_heap performs. There is already a similar, longer comment
block at the top of vacuumlazy.c that mentions lazy_scan_heap directly.
Previously it was impossible to terminate these programs via control-C
while they were prompting for a password. We can fix that trivially
for their initial password prompts, by moving setup of the SIGINT
handler from just before to just after their initial GetConnection()
calls.
This fix doesn't permit escaping out of later re-prompts, but those
should be exceedingly rare, since the user's password or the server's
authentication setup would have to have changed meanwhile. We
considered applying a fix similar to commit 46d665bc2, but that
seemed more complicated than it'd be worth. Moreover, this way is
back-patchable, which that wasn't.
The misbehavior exists in all supported versions, so back-patch to all.
Tom Lane and Nathan Bossart
Discussion: https://postgr.es/m/747443.1635536754@sss.pgh.pa.us
Oversights in commit 405f32fc4.
Also, add a tip (discovered the hard way) about getting Test::More
0.98 to pass its regression tests on recent Linux platforms.
Commit ac9099fc1 rearranged the logic in spgGetCache() that determines
the index's attType (nominal input data type) and leafType (actual
type stored in leaf index tuples). Turns out this broke things for
the case where (a) the actual input data type is different from the
nominal type, (b) the opclass's config function leaves leafType
defaulted, and (c) the opclass has no "compress" function. (b) caused
us to assign the actual input data type as leafType, and then since
that's not attType, we complained that a "compress" function is
required. For non-polymorphic opclasses, condition (a) arises in
binary-compatible cases, such as using SP-GiST text_ops for a varchar
column, or using any opclass on a domain over its nominal input type.
To fix, use attType for leafType when the index's declared column type
is different from but binary-compatible with attType. Do this only in
the defaulted-leafType case, to avoid overriding any explicit
selection made by the opclass.
Per bug #17294 from Ilya Anfimov. Back-patch to v14.
Discussion: https://postgr.es/m/17294-8f6c7962ce877edc@postgresql.org
This fills in the work left un-done by 5f1148224. \prompt can
be canceled out of now, and so can password prompts issued during
\connect. (We don't need to do anything for password prompts
issued during startup, because we aren't yet trapping SIGINT
at that point.)
Nathan Bossart
Discussion: https://postgr.es/m/747443.1635536754@sss.pgh.pa.us
This allows a later commit to reduce the number of branches in performance
sensitive functions during normal running, compared to a very minor saving
during bootstrapping.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-By: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAAKRu_Yeg+vh6SHNEo1+=O7e-BPX35cU0XQM=YwQRnkFyv_y+w@mail.gmail.com
While determining xid horizons, we skip over backends that are running
Vacuum. We also ignore Create Index Concurrently, or Reindex Concurrently
for the purposes of computing Xmin for Vacuum. But we were not setting the
flags corresponding to these operations when they are performed in
parallel which was preventing Xid horizon from advancing.
The optimization related to skipping Create Index Concurrently, or Reindex
Concurrently operations was implemented in PG-14 but the fix is the same
for the Parallel Vacuum as well so back-patched till PG-13.
Author: Masahiko Sawada
Reviewed-by: Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CAD21AoCLQqgM1sXh9BrDFq0uzd3RBFKi=Vfo6cjjKODm0Onr5w@mail.gmail.com
The following improvements are done:
- Addition of some tab completion for CREATE DOMAIN.
- Addition of some tab completion for CREATE TRANSFORM.
- Addition of type completion for CREATE SEQUENCE AS.
Author: Ken Kato
Reviewed-by: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/8d370135aef066659eef8e8fbfa6315b@oss.nttdata.com
We use "clang" to compile bitcode files for LLVM inlining. That might
be different from the build's main C compiler, so it needs its own set
of compiler flags. To simplify configure, we don't bother adding any
-W switches to that flag set; there's little need since the main build
will show us any warnings. However, if we don't want to see unwanted
warnings, we still have to add any -Wno-warning switches we'd normally
use with clang.
This escaped notice before commit 9ff47ea41, which tried to add
-Wno-compound-token-split-by-macro; buildfarm animals using mismatched
CC and CLANG still showed those warnings. I'm not sure why we never
saw any effects from the lack of -Wno-unused-command-line-argument
(maybe that's only activated by -Wall?). clang does not currently
support -Wno-format-truncation or -Wno-stringop-truncation, although
in the interests of future-proofing and consistency I included tests
for those.
Back-patch to v11 where we started building bitcode files.
Discussion: https://postgr.es/m/2921539.1637254619@sss.pgh.pa.us
This commit adds to the main regression test suite a table with all
the in-core data types (some exceptions apply). This table is not
dropped, so as pg_upgrade would be able to check the binary
compatibility of the types tracked in the table. If a new type is added
in core, this part of the tests would need a refresh but the tests are
designed to fail if that were to happen.
As this is useful for upgrades and that these rely on the objects
created in the regression test suite of the old version upgraded from,
a backpatch down to 12 is done, which is the last point where a binary
incompatible change has been done (7c15cef). This will hopefully be
enough to find out if something gets broken during the development of a
new version of Postgres, so as it is possible to take actions in
pg_upgrade itself in this case (like 0ccfc28 for sql_identifier).
An area that is not covered yet is related to external modules, which
may create their own types. The testing infrastructure of pg_upgrade is
not integrated yet with the external modules stored in core
(src/test/modules/ or contrib/, all use the same database name for their
tests so there would be an overlap). This could be improved in the
future.
Author: Justin Pryzby
Reviewed-by: Jacob Champion, Peter Eisentraut, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20201206180248.GI24052@telsasoft.com
Backpatch-through: 12
Up to now, you couldn't escape out of psql's \password command
by typing control-C (or other local spelling of SIGINT). This
is pretty user-unfriendly, so improve it. To do so, we have to
modify the functions provided by pg_get_line.c; but we don't
want to mess with psql's SIGINT handler setup, so provide an
API that lets that handler cause the cancel to occur.
This relies on the assumption that we won't do any major harm by
longjmp'ing out of fgets(). While that's obviously a little shaky,
we've long had the same assumption in the main input loop, and few
issues have been reported.
psql has some other simple_prompt() calls that could usefully
be improved the same way; for now, just deal with \password.
Nathan Bossart, minor tweaks by me
Discussion: https://postgr.es/m/747443.1635536754@sss.pgh.pa.us
This fills in some gaps in planner support for starts_with() and
the equivalent ^@ operator:
* A condition such as "textcol ^@ constant" can now use a regular
btree index, not only an SP-GiST index, so long as the index's
collation is C. (This works just like "textcol LIKE 'foo%'".)
* "starts_with(textcol, constant)" can be optimized the same as
"textcol ^@ constant".
* Fixed-prefix LIKE and regex patterns are now more like starts_with()
in another way: if you apply one to an SPGiST-indexed column, you'll
get an index condition using ^@ rather than two index conditions with
>= and <.
Per a complaint from Shay Rojansky. Patch by me; thanks to
Nathan Bossart for review.
Discussion: https://postgr.es/m/232599.1633800229@sss.pgh.pa.us
The error handling here was a mess, as a result of a fundamentally
bad design (relying on errno to keep its value much longer than is
safe to assume) as well as a lot of just plain sloppiness, both as
to noticing errors at all and as to reporting the correct errno.
Moreover, the recent addition of LZ4 compression broke things
completely, because liblz4 doesn't use errno to report errors.
To improve matters, keep the error state in the DirectoryMethodData or
TarMethodData struct, and add a string field so we can handle cases
that don't set errno. (The tar methods already had a version of this,
but it can be done more efficiently since all these cases use a
constant error string.) Make the dir and tar methods handle errors
in basically identical ways, which they didn't before.
This requires copying errno into the state struct in a lot of places,
which is a bit tedious, but it has the virtue that we can get rid of
ad-hoc code to save and restore errno in a number of places ... not
to mention that it fixes other places that should've saved/restored
errno but neglected to.
In passing, fix some pointlessly static buffers to be ordinary
local variables.
There remains an issue about exactly how to handle errors from
fsync(), but that seems like material for its own patch.
While the LZ4 problems are new, all the rest of this is fixes for
old bugs, so backpatch to v10 where walmethods.c was introduced.
Patch by me; thanks to Michael Paquier for review.
Discussion: https://postgr.es/m/1343113.1636489231@sss.pgh.pa.us
Coverity complained that applying get_gz_error after a failed gzclose,
as we did in one place in pg_basebackup, is unsafe. I think it's
right: it's entirely likely that the call is touching freed memory.
Change that to inspect errno, as we do for other gzclose calls.
Also, be careful to initialize errno to zero immediately before any
gzclose() call where we care about the error status. (There are
some calls where we don't, because we already failed at some previous
step.) This ensures that we don't get a misleadingly irrelevant
error code if gzclose() fails in a way that doesn't set errno.
We could work harder at that, but it looks to me like all such cases
are basically can't-happen if we're not misusing zlib, so it's
not worth the extra notational cruft that would be required.
Also, fix several places that simply failed to check for close-time
errors at all, mostly at some remove from the close or gzclose itself;
and one place that did check but didn't bother to report the errno.
Back-patch to v12. These mistakes are older than that, but between
the frontend logging API changes that happened in v12 and the fact
that frontend code can't rely on %m before that, the patch would need
substantial revision to work in older branches. It doesn't quite
seem worth the trouble given the lack of related field complaints.
Patch by me; thanks to Michael Paquier for review.
Discussion: https://postgr.es/m/1343113.1636489231@sss.pgh.pa.us
If a SQL-standard function body contains an INSERT ... SELECT statement,
any function parameters referenced within the SELECT were always printed
in $N style, rather than using the parameter name if any. While not
strictly incorrect, this wasn't the intention, and it's inconsistent
with the way that such parameters would be printed in any other kind
of statement.
The cause is that the recursion to get_query_def from
get_insert_query_def neglected to pass down the context->namespaces
list, passing constant NIL instead. This is a very ancient oversight,
but AFAICT it had no visible consequences before commit e717a9a18
added an outermost namespace with function parameters. We don't allow
INSERT ... SELECT as a sub-query, except in a top-level WITH clause,
where it couldn't contain any outer references that might need to access
upper namespaces. So although that's arguably a bug, I don't see any
point in changing it before v14.
In passing, harden the code added to get_parameter by e717a9a18 so that
it won't crash if a PARAM_EXTERN Param appears in an unexpected place.
Per report from Erki Eessaar. Code fix by me, regression test case
by Masahiko Sawada.
Discussion: https://postgr.es/m/AM9PR01MB8268347BED344848555167FAFE949@AM9PR01MB8268.eurprd01.prod.exchangelabs.com
Commit 81d5995b4b introduced more fine-grained errormessages for
incorrect relkinds for publication, while unlogged and temporary
tables were reported with using the same message. This provides
separate error messages for these types of relpersistence.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Jeevan Ladhe <jeevan.ladhe@enterprisedb.com>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://postgr.es/m/CALj2ACW9S=AswyQHjtO6WMcsergMkCBTtzXGrM8DX26DzfeTLQ@mail.gmail.com
The "See also" section on the reference page for CREATE PUBLICATION
didn't match the cross references on CREATE SUBSCRIPTION and their
ALTER counterparts. Fixed by adding an xref to the CREATE and ALTER
SUBSCRIPTION pages. Backpatch down to v10 where CREATE PUBLICATION
was introduced.
Author: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAHut+PvGWd3-Ktn96c-z6uq-8TGVVP=TPOkEovkEfntoo2mRhw@mail.gmail.com
Backpatch-through: 10
At present, there is an undocumented coding rule that you must call
RecoveryInProgress(), or do something else that results in a call
to InitXLogInsert(), before trying to write WAL. Otherwise, the
WAL construction buffers won't be initialized, resulting in
failures.
Since it's not good to rely on a status inquiry function like
RecoveryInProgress() having the side effect of initializing
critical data structures, instead do the initialization eariler,
when the backend first starts up.
Patch by me. Reviewed by Nathan Bossart and Michael Paquier.
Discussion: http://postgr.es/m/CA+TgmoY7b65qRjzHN_tWUk8B4sJqk1vj1d31uepVzmgPnZKeLg@mail.gmail.com
When changing REPLICA IDENTITY INDEX to another one, the target table's
relcache was not being invalidated. This leads to skipping update/delete
operations during apply on the subscriber side as the columns required to
search corresponding rows won't get logged.
Author: Tang Haiying, Hou Zhijie
Reviewed-by: Euler Taveira, Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/OS0PR01MB61133CA11630DAE45BC6AD95FB939@OS0PR01MB6113.jpnprd01.prod.outlook.com
Add a comment explaining why the pgstats accounting used during
opportunistic heap pruning operations (to maintain the current number of
dead tuples in the relation) needs to compensate by subtracting away the
number of new LP_DEAD items. This is needed so it can avoid completely
forgetting about tuples that become LP_DEAD items during pruning -- they
should still count.
It seems more natural to discuss this issue at the only relevant call
site (opportunistic pruning), since the same issue does not apply to the
only other caller (the VACUUM call site). Move everything there too.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzm7f+A6ej650gi_ifTgbhsadVW5cujAL3punpupHff5Yg@mail.gmail.com
Commit 90627cf98 added support for retaining the data directory even on
successful tests, but failed to document the environment variable which
controls retention. This adds a small note to the TAP test README about
PG_TEST_NOCLEAN which when set skips removing the data directories from
successful tests.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2B02C1B3-3F41-4E14-92B9-005D83623A0B@yesql.se
The documentation says plainly that \password acts on "the current user"
by default. What it actually acted on, or tried to, was the username
used to log into the current session. This is not the same thing if
one has since done SET ROLE or SET SESSION AUTHENTICATION. Aside from
the possible surprise factor, it's quite likely that the current role
doesn't have permissions to set the password of the original role.
To fix, use "SELECT CURRENT_USER" to get the role name to act on.
(This syntax works with servers at least back to 7.0.) Also, in
hopes of reducing confusion, include the role name that will be
acted on in the password prompt.
The discrepancy from the documentation makes this a bug, so
back-patch to all supported branches.
Patch by me; thanks to Nathan Bossart for review.
Discussion: https://postgr.es/m/747443.1635536754@sss.pgh.pa.us
When deparsing an expression of the form "remote_var OP constant",
we'd normally apply a cast to the constant to make sure that the
remote parser thinks it's of the same type we do. However, doing
so is often not necessary, and it causes problems if the user has
intentionally declared the local column as being of a different
type than the remote column. A plausible use-case for that is
using text to represent a type that's an enum on the remote side.
A comparison on such a column will get shipped as "var = 'foo'::text",
which blows up on the remote side because there's no enum = text
operator. But if we simply leave off the explicit cast, the
comparison will do exactly what the user wants.
It's possible to do this without major risk of semantic problems, by
relying on the longstanding parser heuristic that "if one operand of
an operator is of type unknown, while the other one has a known type,
assume that the unknown operand is also of that type". Hence, this
patch leaves off the cast only if (a) the operator inputs have the same
type locally; (b) the constant will print as a string literal or NULL,
both of which are initially taken as type unknown; and (c) the non-Const
input is a plain foreign Var. Rule (c) guarantees that the remote
parser will know the type of the non-Const input; moreover, it means
that if this cast-omission does cause any semantic surprises, that can
only happen in cases where the local column has a different type than
the remote column. That wasn't guaranteed to work anyway, and this
patch should represent a net usability gain for such cases.
One point that I (tgl) remain slightly uncomfortable with is that we
will ignore an implicit RelabelType when deciding if the non-Const input
is a plain Var. That makes it a little squishy to argue that the remote
should resolve the Const as being of the same type as its Var, because
then our Const is not the same type as our Var. However, if we don't do
that, then this hack won't work as desired if the user chooses to use
varchar rather than text to represent some remote column. That seems
useful, so do it like this for now. We might have to give up the
RelabelType-ignoring bit if any problems surface.
Dian Fay, with review and kibitzing by me
Discussion: https://postgr.es/m/C9LU294V7K4F.34LRRDU449O45@lamia
Configure tests for the presence of perl modules required for TAP tests,
and that they meet specified minimum version requirements. This patch
makes it report the version of the module that's actually found rather
than just an 'ok' message. This will help in deciding if we can upgrade
minimum requirements for these modules.
Discussion: https://postgr.es/m/f5e1d308-4e33-37a7-bdf1-f6e0c75119de@dunslane.net
pg_stat_get_slru() in pgstatfuncs.c would point to one element after the
end of the array PgStat_SLRUStats when finishing to scan its entries.
This had no direct consequences as no data from the extra memory area
was read, but static analyzers would rightfully complain here. So let's
be clean.
While on it, this adds one regression test in the area reserved for
system views.
Reported-by: Alexander Kozhemyakin, via AddressSanitizer
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/17280-37da556e86032070@postgresql.org
Backpatch-through: 13
