A few questionable partitioning designs have been cropping up lately
around the mailing lists. Generally, these cases have been partitioning
using too many partitions which have caused performance or OOM problems for
the users.
Since we have very little else to guide users into good design, here we
add a new section to the partitioning documentation with some best
practise guidelines for good design.
Reviewed-by: Justin Pryzby, Amit Langote, Alvaro Herrera
Discussion: https://postgr.es/m/CAKJS1f-2rx+E9mG3xrCVHupefMjAp1+tpczQa9SEOZWyU7fjEA@mail.gmail.com
Backpatch-through: 10
json_to_record(), when an output column is declared as type json or jsonb,
should emit the corresponding field of the input JSON object. But it got
this slightly wrong when the field is just a string literal: it failed to
escape the contents of the string. That typically resulted in syntax
errors if the string contained any double quotes or backslashes.
jsonb_to_record() handles such cases correctly, but I added corresponding
test cases for it too, to prevent future backsliding.
Improve the documentation, as it provided only a very hand-wavy
description of the conversion rules used by these functions.
Per bug report from Robert Vollmert. Back-patch to v10 where the
error was introduced (by commit cf35346e8).
Note that PG 9.4 - 9.6 also get this case wrong, but differently so:
they feed the de-escaped contents of the string literal to json[b]_in.
That behavior is less obviously wrong, so possibly it's being depended on
in the field, so I won't risk trying to make the older branches behave
like the newer ones.
Discussion: https://postgr.es/m/D6921B37-BD8E-4664-8D5F-DB3525765DCD@vllmrt.net
Vignesh found this bug in the check function for
default_table_access_method's check hook, but that was just copied
from older GUCs. Investigation by Michael and me then found the bug in
further places.
When not connected to a database (e.g. in a walsender connection), we
cannot perform (most) GUC checks that need database access. Even when
only shared tables are needed, unless they're
nailed (c.f. RelationCacheInitializePhase2()), they cannot be accessed
without pg_class etc. being present.
Fix by extending the existing IsTransactionState() checks to also
check for MyDatabaseOid.
Reported-By: Vignesh C, Michael Paquier, Andres Freund
Author: Vignesh C, Andres Freund
Discussion: https://postgr.es/m/CALDaNm1KXK9gbZfY-p_peRFm_XrBh1OwQO1Kk6Gig0c0fVZ2uw%40mail.gmail.com
Backpatch: 9.4-
Using PARTITION OF can result in column ordering being changed from the
database being dumped, if the partition uses a column layout different
from the parent's. It's not pg_dump's job to editorialize on table
definitions, so this is not acceptable; back-patch all the way back to
pg10, where partitioned tables where introduced.
This change also ensures that partitions end up in the correct
tablespace, if different from the parent's; this is an oversight in
ca4103025d (in pg12 only). Partitioned indexes (in pg11) don't have
this problem, because they're already created as independent indexes and
attached to their parents afterwards.
This change also has the advantage that the partition is restorable from
the dump (as a standalone table) even if its parent table isn't
restored.
The original commits (3b23552ad8 in branch master) failed to cover
subsidiary column elements correctly, such as NOT NULL constraint and
CHECK constraints, as reported by Rushabh Lathia (initially as a failure
to restore serial columns). They were reverted. This recapitulation
commit fixes those problems.
Add some pg_dump tests to verify these things more exhaustively,
including constraints with legacy-inheritance tables, which were not
tested originally. In branches 10 and 11, add a local constraint to the
pg_dump test partition that was added by commit 2d7eeb1b14 to master.
Author: Álvaro Herrera, David Rowley
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/CAKJS1f_1c260nOt_vBJ067AZ3JXptXVRohDVMLEBmudX1YEx-A@mail.gmail.com
Discussion: https://postgr.es/m/20190423185007.GA27954@alvherre.pgsql
Discussion: https://postgr.es/m/CAGPqQf0iQV=PPOv2Btog9J9AwOQp6HmuVd6SbGTR_v3Zp2XT1w@mail.gmail.com
Descriptions of pg_trgm GUC options have % replaced with %% like it was
a printf-like format. But that's not needed since they are just plain strings.
This commit fixed that. Backpatch to last supported version since this error
present from the beginning.
Reported-by: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoAgPKODUsu9gqUFiNqEOAqedStxJ-a0sapsJXWWAVp%3Dxg%40mail.gmail.com
Backpatch-through: 9.4
It's harmless to call PQfreemem() with a NULL argument, so the only
consequence was that if allocating 'schema' failed, but allocating 'table'
or 'field' succeeded, we would leak a bit of memory. That's highly
unlikely to happen, so this is just academical, but let's get it right.
Per bug #15838 from Timur Birsh. Backpatch back to 9.5, where the
PQfreemem() calls were introduced.
Discussion: https://www.postgresql.org/message-id/15838-3221652c72c5e69d@postgresql.org
Continuous operation cannot be achieved without applying this technique,
so it needs to be properly described.
Author: Álvaro Herrera
Reported-by: Tom Lane
Discussion: https://postgr.es/m/8756.1556302759@sss.pgh.pa.us
A parallel worker process should not be making any decisions of its
own about whether to auto-explain. If the parent session process
passed down flags asking for instrumentation data, do that, otherwise
not. Trying to enable instrumentation anyway leads to bugs like the
"could not find key N in shm TOC" failure reported in bug #15821
from Christian Hofstaedtler.
We can implement this cheaply by piggybacking on the existing logic
for not doing anything when we've chosen not to sample a statement.
While at it, clean up some tin-eared coding related to the sampling
feature, including an off-by-one error that meant that asking for 1.0
sampling rate didn't actually result in sampling every statement.
Although the specific case reported here only manifested in >= v11,
I believe that related misbehaviors can be demonstrated in any version
that has parallel query; and the off-by-one error is certainly there
back to 9.6 where that feature was added. So back-patch to 9.6.
Discussion: https://postgr.es/m/15821-5eb422e980594075@postgresql.org
It's not really supported to call systable_getnext() in a different
memory context than systable_beginscan() was called in, and it's
*definitely* not safe to do so and then reset that context between
calls. I'm not very clear on how this code survived
CLOBBER_CACHE_ALWAYS testing ... but Alexander Lakhin found a case
that would crash it pretty reliably.
Per bug #15828. Fix, and backpatch to v11 where this code came in.
Discussion: https://postgr.es/m/15828-f6ddd7df4852f473@postgresql.org
Support of CHECK OPTION for updatable views has been added in 9.4, but
the documentation of information_schema never got the call even if the
information displayed is correct.
Author: Gilles Darold
Discussion: https://postgr.es/m/75d07704-6c74-4f26-656a-10045c01a17e@darold.net
Backpatch-through: 9.4
Most errors reported in extended statistics are internal issues, and so
should use elog(). The MCV list code was already following this rule, but
the functional dependencies and ndistinct coefficients were using a mix
of elog() and ereport(). Fix this by changing most places to elog(), with
the exception of input functions.
This is a mostly cosmetic change, it makes the life a little bit easier
for translators, as elog() messages are not translated. So backpatch to
PostgreSQL 10, where extended statistics were introduced.
Author: Tomas Vondra
Backpatch-through: 10 where extended statistics were added
Discussion: https://postgr.es/m/20190503154404.GA7478@alvherre.pgsql
When this suite runs installcheck, redirect file creations from
src/test/regress to src/bin/pg_upgrade/tmp_check/regress. This closes a
race condition in "make -j check-world". If the pg_upgrade suite wrote
to a given src/test/regress/results file in parallel with the regular
src/test/regress invocation writing it, a test failed spuriously. Even
without parallelism, in "make -k check-world", the suite finishing
second overwrote the other's regression.diffs. This revealed test
"largeobject" assuming @abs_builddir@ is getcwd(), so fix that, too.
Buildfarm client REL_10, released fifty-four days ago, supports saving
regression.diffs from its new location. When an older client reports a
pg_upgradeCheck failure, it will no longer include regression.diffs.
Back-patch to 9.5, where pg_upgrade moved to src/bin.
Reviewed (in earlier versions) by Andrew Dunstan.
Discussion: https://postgr.es/m/20181224034411.GA3224776@rfd.leadboat.com
This allows "vcregress upgradecheck" to pass twice in immediate
succession, and it's more like how $(prove_check) works. Back-patch to
9.5, where pg_upgrade moved to src/bin.
Discussion: https://postgr.es/m/20190520012436.GA1480421@rfd.leadboat.com
On master (after 700538) the old version's installed psql was used -
even when the old version might not actually be installed / might be
installed into a temporary directory. As commonly the case when just
executing make check for pg_upgrade, as $oldbindir is just the current
version's $bindir.
In the back branches, with --install specified, psql from the new
version's temporary installation was used, without --install (e.g for
NO_TEMP_INSTALL, cf 47b3c26642), the new version's installed psql was
used (which might or might not exist).
Author: Andres Freund
Discussion: https://postgr.es/m/20190522175150.c26f4jkqytahajdg@alap3.anarazel.de
When there were duplicate columns in the hash key list, the array
sizes could be miscomputed, resulting in access off the end of the
array. Adjust the computation to ensure the array is always large
enough.
(I considered whether the duplicates could be removed in planning, but
I can't rule out the possibility that duplicate columns might have
different hash functions assigned. Simpler to just make sure it works
at execution time regardless.)
Bug apparently introduced in fc4b3dea2 as part of narrowing down the
tuples stored in the hashtable. Reported by Colm McHugh of Salesforce,
though I didn't use their patch. Backpatch back to version 10 where
the bug was introduced.
Discussion: https://postgr.es/m/CAFeeJoKKu0u+A_A9R9316djW-YW3-+Gtgvy3ju655qRHR3jtdA@mail.gmail.com
This uses a method similar to 68a7c24f and now b8c6014 (applied for
database creation), which guarantees that GRANT commands using the WITH
GRANT OPTION are dumped in a way so as cascading dependencies are
respected. Note that tablespaces do not have support for initial
privileges via pg_init_privs, so the same method needs to be applied
again. It would be nice to merge all the logic generating ACL queries
in dumps under the same banner, but this requires extending the support
of pg_init_privs to objects that cannot use it yet, so this is left as
future work.
Discussion: https://postgr.es/m/20190522071555.GB1278@paquier.xyz
Author: Michael Paquier
Reviewed-by: Nathan Bossart
Backpatch-through: 9.6
This uses a method similar to 68a7c24f, which guarantees that GRANT
commands using the WITH GRANT OPTION are dumped in a way so as cascading
dependencies are respected. As databases do not have support for
initial privileges via pg_init_privs, we need to repeat again the same
ACL reordering method.
ACL for databases have been moved from pg_dumpall to pg_dump in v11, so
this impacts pg_dump for v11 and above, and pg_dumpall for v9.6 and
v10.
Discussion: https://postgr.es/m/15788-4e18847520ebcc75@postgresql.org
Author: Nathan Bossart
Reviewed-by: Haribabu Kommi
Backpatch-through: 9.6
For partial aggregation combine steps,
AggStatePerTrans->numTransInputs was set to the transition function's
number of inputs, rather than the combine function's number of
inputs (always 1).
That lead to partial aggregates with strict combine functions to
wrongly check for NOT NULL input as required by strictness. When the
aggregate wasn't exactly passed one argument, the strictness check was
either omitted (in the 0 args case) or too many arguments were
checked. In the latter case we'd read beyond the end of
FunctionCallInfoData->args (only in master).
AggStatePerTrans->numTransInputs actually has been wrong since since
9.6, where partial aggregates were added. But it turns out to not be
an active problem in 9.6 and 10, because numTransInputs wasn't used at
all for combine functions: Before c253b722f6 there simply was no NULL
check for the input to strict trans functions, and after that the
check was simply hardcoded for the right offset in fcinfo, as it's
done by code specific to combine functions.
In bf6c614a2f (11) the strictness check was generalized, with common
code doing the strictness checks for both plain and combine transition
functions, based on numTransInputs. For combine functions this lead to
not emitting an expression step to check for strict input in the 0
arguments case, and in the > 1 arguments case, we'd check too many
arguments.Due to the fact that the relevant fcinfo->isnull[2..] was
always zero-initialized (more or less by accident, by being part of
the AggStatePerTrans struct, which is palloc0'ed), there was no
observable damage in the latter case before a9c35cf85c, we just
checked too many array elements.
Due to the changes in a9c35cf85c, > 1 argument bug became visible,
because these days fcinfo is a) dynamically allocated without being
zeroed b) exactly the length required for the number of specified
arguments (hardcoded to 2 in this case).
This commit only contains a fairly minimal fix, setting numTransInputs
to a hardcoded 1 when building a pertrans for a combine function. It
seems likely that we'll want to clean this up further (e.g. the
arguments build_pertrans_for_aggref() aren't particularly meaningful
for combine functions). But the wrap date for 12 beta1 is coming up
fast, so it seems good to have a minimal fix in place.
Backpatch to 11. While AggStatePerTrans->numTransInputs was set
wrongly before that, the value was not used for combine functions.
Reported-By: Rajkumar Raghuwanshi
Diagnosed-By: Kyotaro Horiguchi, Jeevan Chalke, Andres Freund, David Rowley
Author: David Rowley, Kyotaro Horiguchi, Andres Freund
Discussion: https://postgr.es/m/CAKcux6=uZEyWyLw0N7HtR9OBc-sWEFeByEZC7t-KDf15FKxVew@mail.gmail.com
When this suite runs installcheck, redirect file creations from
src/test/regress to src/bin/pg_upgrade/tmp_check/regress. This closes a
race condition in "make -j check-world". If the pg_upgrade suite wrote
to a given src/test/regress/results file in parallel with the regular
src/test/regress invocation writing it, a test failed spuriously. Even
without parallelism, in "make -k check-world", the suite finishing
second overwrote the other's regression.diffs. This revealed test
"largeobject" assuming @abs_builddir@ is getcwd(), so fix that, too.
Buildfarm client REL_10, released forty-five days ago, supports saving
regression.diffs from its new location. When an older client reports a
pg_upgradeCheck failure, it will no longer include regression.diffs.
Back-patch to 9.5, where pg_upgrade moved to src/bin.
Reviewed by Andrew Dunstan.
Discussion: https://postgr.es/m/20181224034411.GA3224776@rfd.leadboat.com
Previously, gen_partprune_steps() always built executor pruning steps
using all suitable clauses, including those containing PARAM_EXEC
Params. This meant that the pruning steps were only completely safe
for executor run-time (scan start) pruning. To prune at executor
startup, we had to ignore the steps involving exec Params. But this
doesn't really work in general, since there may be logic changes
needed as well --- for example, pruning according to the last operator's
btree strategy is the wrong thing if we're not applying that operator.
The rules embodied in gen_partprune_steps() and its minions are
sufficiently complicated that tracking their incremental effects in
other logic seems quite impractical.
Short of a complete redesign, the only safe fix seems to be to run
gen_partprune_steps() twice, once to create executor startup pruning
steps and then again for run-time pruning steps. We can save a few
cycles however by noting during the first scan whether we rejected
any clauses because they involved exec Params --- if not, we don't
need to do the second scan.
In support of this, refactor the internal APIs in partprune.c to make
more use of passing information in the GeneratePruningStepsContext
struct, rather than as separate arguments.
This is, I hope, the last piece of our response to a bug report from
Alan Jackson. Back-patch to v11 where this code came in.
Discussion: https://postgr.es/m/FAD28A83-AC73-489E-A058-2681FA31D648@tvsquared.com
gen_prune_steps_from_opexps's notion of how to do this was overly
complicated and underly correct.
Per discussion of a report from Alan Jackson (though this fixes only one
aspect of that problem). Back-patch to v11 where this code came in.
Amit Langote
Discussion: https://postgr.es/m/FAD28A83-AC73-489E-A058-2681FA31D648@tvsquared.com
Cross-type comparison operators in a btree or hash opclass might be
only stable not immutable (this is true of timestamp vs. timestamptz
for example). partprune.c ignored this possibility and would perform
plan-time pruning with them anyway, possibly leading to wrong answers
if the environment changed between planning and execution.
To fix, teach gen_partprune_steps() to do things differently when
creating plan-time pruning steps vs. run-time pruning steps.
analyze_partkey_exprs() also needs an extra check, which is rather
annoying but now is not the time to restructure things enough to
avoid that.
While at it, simplify the logic for the plan-time case a little
by insisting that the comparison value be a Const and nothing else.
This relies on the assumption that eval_const_expressions will have
reduced any immutable expression to a Const; which is not quite
100% true, but certainly any case that comes up often enough to be
interesting should have simplification logic there.
Also improve a bunch of inadequate/obsolete/wrong comments.
Per discussion of a report from Alan Jackson (though this fixes only one
aspect of that problem). Back-patch to v11 where this code came in.
David Rowley, with some further hacking by me
Discussion: https://postgr.es/m/FAD28A83-AC73-489E-A058-2681FA31D648@tvsquared.com
This path previously was not reliably covered. There was some
heuristic coverage via insert-conflict-toast.spec, but that test is
not deterministic, and only tested for a somewhat specific bug.
Backpatch, as this is a complicated and otherwise untested code
path. Unfortunately 9.5 cannot handle two waiting sessions, and thus
cannot execute this test.
Triggered by a conversion with Melanie Plageman.
Author: Andres Freund
Discussion: https://postgr.es/m/CAAKRu_a7hbyrk=wveHYhr4LbcRnRCG=yPUVoQYB9YO1CdUBE9Q@mail.gmail.com
Backpatch: 9.5-
The conditions listed in this comment have changed several times, and at
some point the thing that the "if so" referred to was negated.
The text was OK up to 9.6. It was differently wrong in v10, v11 and
master, so fix in all those versions.
An upcoming HEAD-only patch will standardize the terminology around
ItemIdData variables/line pointers, ending the practice of referring to
them as "item pointers". Make the "Database Page Layout" docs
consistent with the new policy. The term "item identifier" is already
used in the same section, so stick with that.
Discussion: https://postgr.es/m/CAH2-Wz=c=MZQjUzde3o9+2PLAPuHTpVZPPdYxN=E4ndQ2--8ew@mail.gmail.com
Backpatch: All supported branches.
Only hand-assigned type OIDs should be presumed to match across different
PG servers; those assigned during genbki.pl or during initdb are likely
to change due to addition or removal of unrelated objects.
This means that the cutoff should be FirstGenbkiObjectId (in HEAD)
or FirstBootstrapObjectId (before that), not FirstNormalObjectId.
Compare postgres_fdw's is_builtin() test.
It's likely that this error has no observable consequence in a
normally-functioning system, since ATM the only affected type OIDs are
system catalog rowtypes and information_schema types, which would not
typically be interesting for logical replication. But you could
probably break it if you tried hard, so back-patch.
Discussion: https://postgr.es/m/15150.1557257111@sss.pgh.pa.us
Commit 8fa30f906b reduced the elevel of a number of "can't happen"
_bt_split() errors from PANIC to ERROR. At the same time, the new right
page buffer for the split could continue to be acquired well before the
critical section. This was possible because it was relatively
straightforward to make sure that _bt_split() could not throw an error,
with a few specific exceptions. The exceptional cases were safe because
they involved specific, well understood errors, making it possible to
consistently zero the right page before actually raising an error using
elog(). There was no danger of leaving around a junk page, provided
_bt_split() stuck to this coding rule.
Commit 8224de4f, which introduced INCLUDE indexes, added code to make
_bt_split() truncate away non-key attributes. This happened at a point
that broke the rule around zeroing the right page in _bt_split(). If
truncation failed (perhaps due to palloc() failure), that would result
in an errant right page buffer with junk contents. This could confuse
VACUUM when it attempted to delete the page, and should be avoided on
general principle.
To fix, reorganize _bt_split() so that truncation occurs before the new
right page buffer is even acquired. A junk page/buffer will not be left
behind if _bt_nonkey_truncate()/_bt_truncate() raise an error.
Discussion: https://postgr.es/m/CAH2-WzkcWT_-NH7EeL=Az4efg0KCV+wArygW8zKB=+HoP=VWMw@mail.gmail.com
Backpatch: 11-, where INCLUDE indexes were introduced.
pgtls_read_pending is declared to return bool, but what the underlying
SSL_pending function returns is a count of available bytes.
This is actually somewhat harmless if we're using C99 bools, but in
the back branches it's a live bug: if the available-bytes count happened
to be a multiple of 256, it would get converted to a zero char value.
On machines where char is signed, counts of 128 and up could misbehave
as well. The net effect is that when using SSL, libpq might block
waiting for data even though some has already been received.
Broken by careless refactoring in commit 4e86f1b16, so back-patch
to 9.5 where that came in.
Per bug #15802 from David Binderman.
Discussion: https://postgr.es/m/15802-f0911a97f0346526@postgresql.org
A bounded quantifier with m = n = 1 might be thought a no-op. But
according to our documentation (which traces back to Henry Spencer's
original man page) it still imposes greediness, or non-greediness in the
case of the non-greedy variant "{1,1}?", on whatever it's attached to.
This turns out not to work though, because parseqatom() optimizes away
the m = n = 1 case without regard for whether it's supposed to change
the greediness of the argument RE.
We can fix this by just not applying the optimization when the greediness
needs to change; the subsequent general cases handle it fine.
The three cases in which we can still apply the optimization are
(a) no quantifier, or quantifier does not impose a preference;
(b) atom has no greediness property, implying it cannot match a
variable amount of text anyway; or
(c) quantifier's greediness is same as atom's.
Note that in most cases where one of these applies, we'd have exited
earlier in the "not a messy case" fast path. I think it's now only
possible to get to the optimization when the atom involves capturing
parentheses or a non-top-level backref.
Back-patch to all supported branches. I'd ordinarily be hesitant to
put a subtle behavioral change into back branches, but in this case
it's very hard to see a reason why somebody would write "{1,1}?" unless
they're trying to get the documented change-of-greediness behavior.
Discussion: https://postgr.es/m/5bb27a41-350d-37bf-901e-9d26f5592dd0@charter.net
The function had been interpreting SQL_ASCII messages as UTF8, throwing
an error when they were invalid UTF8. The new behavior is consistent
with pg_do_encoding_conversion(). This affects LOG_DESTINATION_STDERR
and LOG_DESTINATION_EVENTLOG, which will send untranslated bytes to
write() and ReportEventA(). On buildfarm member bowerbird, enabling
log_connections caused an error whenever the role name was not valid
UTF8. Back-patch to 9.4 (all supported versions).
Discussion: https://postgr.es/m/20190512015615.GD1124997@rfd.leadboat.com
We long ago decided to design the shared PgBackendStatus data structure to
minimize the cost of writing status updates, which means that writers just
have to increment the st_changecount field twice. That isn't hooked into
any sort of resource management mechanism, which means that if something
were to throw error between the two increments, the st_changecount field
would be left odd indefinitely. That would cause readers to lock up.
Now, since it's also a bad idea to leave the field odd for longer than
absolutely necessary (because readers will spin while we have it set),
the expectation was that we'd treat these segments like spinlock critical
sections, with only short, more or less straight-line, code in them.
That was fine as originally designed, but commit 9029f4b37 broke it
by inserting a significant amount of non-straight-line code into
pgstat_bestart(), code that is very capable of throwing errors, not to
mention taking a significant amount of time during which readers will spin.
We have a report from Neeraj Kumar of readers actually locking up, which
I suspect was due to an encoding conversion error in X509_NAME_to_cstring,
though conceivably it was just a garden-variety OOM failure.
Subsequent commits have loaded even more dubious code into pgstat_bestart's
critical section (and commit fc70a4b0d deserves some kind of booby prize
for managing to miss the critical section entirely, although the negative
consequences seem minimal given that the PgBackendStatus entry should be
seen by readers as inactive at that point).
The right way to fix this mess seems to be to compute all these values
into a local copy of the process' PgBackendStatus struct, and then just
copy the data back within the critical section proper. This plan can't
be implemented completely cleanly because of the struct's heavy reliance
on out-of-line strings, which we must initialize separately within the
critical section. But still, the critical section is far smaller and
safer than it was before.
In hopes of forestalling future errors of the same ilk, rename the
macros for st_changecount management to make it more apparent that
the writer-side macros create a critical section. And to prevent
the worst consequences if we nonetheless manage to mess it up anyway,
adjust those macros so that they really are a critical section, ie
they now bump CritSectionCount. That doesn't add much overhead, and
it guarantees that if we do somehow throw an error while the counter
is odd, it will lead to PANIC and a database restart to reset shared
memory.
Back-patch to 9.5 where the problem was introduced.
In HEAD, also fix an oversight in commit b0b39f72b: it failed to teach
pgstat_read_current_status to copy st_gssstatus data from shared memory to
local memory. Hence, subsequent use of that data within the transaction
would potentially see changing data that it shouldn't see.
Discussion: https://postgr.es/m/CAPR3Wj5Z17=+eeyrn_ZDG3NQGYgMEOY6JV6Y-WRRhGgwc16U3Q@mail.gmail.com
The buildfarm client uses TEMP_CONFIG to implement its extra_config
setting. Except for stats_temp_directory, extra_config now applies to
TAP suites; extra_config values seen in the past month are compatible
with this. Back-patch to 9.6, where PostgresNode was introduced, so the
buildfarm can rely on it sooner.
Reviewed by Andrew Dunstan and Tom Lane.
Discussion: https://postgr.es/m/20181229021950.GA3302966@rfd.leadboat.com
When failing to reindex a table or an index, reindexdb would generate an
extra error message related to a database failure, which is misleading.
Backpatch all the way down, as this has been introduced by 85e9a5a0.
Discussion: https://postgr.es/m/CAOBaU_Yo61RwNO3cW6WVYWwH7EYMPuexhKqufb2nFGOdunbcHw@mail.gmail.com
Author: Julien Rouhaud
Reviewed-by: Daniel Gustafsson, Álvaro Herrera, Tom Lane, Michael
Paquier
Backpatch-through: 9.4
There's a very old race condition in our code to see whether a pre-existing
shared memory segment is still in use by a conflicting postmaster: it's
possible for the other postmaster to remove the segment in between our
shmctl() and shmat() calls. It's a narrow window, and there's no risk
unless both postmasters are using the same port number, but that's possible
during parallelized "make check" tests. (Note that while the TAP tests
take some pains to choose a randomized port number, pg_regress doesn't.)
If it does happen, we treated that as an unexpected case and errored out.
To fix, allow EINVAL to be treated as segment-not-present, and the same
for EIDRM on Linux. AFAICS, the considerations here are basically
identical to the checks for acceptable shmctl() failures, so I documented
and coded it that way.
While at it, adjust PGSharedMemoryAttach's API to remove its undocumented
dependency on UsedShmemSegAddr in favor of passing the attach address
explicitly. This makes it easier to be sure we're using a null shmaddr
when probing for segment conflicts (thus avoiding questions about what
EINVAL means). I don't think there was a bug there, but it required
fragile assumptions about the state of UsedShmemSegAddr during
PGSharedMemoryIsInUse.
Commit c09850992 may have made this failure more probable by applying
the conflicting-segment tests more often. Hence, back-patch to all
supported branches, as that was.
Discussion: https://postgr.es/m/22224.1557340366@sss.pgh.pa.us
create_merge_append_plan failed to honor the CP_EXACT_TLIST flag:
it would generate the expected targetlist but then it felt free to
add resjunk sort targets to it. This demonstrably leads to assertion
failures in v11 and HEAD, and it's probably just accidental that we
don't see the same in older branches. I've not looked into whether
there would be any real-world consequences in non-assert builds.
In HEAD, create_append_plan has sprouted the same problem, so fix
that too (although we do not have any test cases that seem able to
reach that bug). This is an oversight in commit 3fc6e2d7f which
invented the CP_EXACT_TLIST flag, so back-patch to 9.6 where that
came in.
convert_subquery_pathkeys would create pathkeys for subquery output
values if they match any EquivalenceClass known in the outer query
and are available in the subquery's syntactic targetlist. However,
the second part of that condition is wrong, because such values might
not appear in the subquery relation's reltarget list, which would
mean that they couldn't be accessed above the level of the subquery
scan. We must check that they appear in the reltarget list, instead.
This can lead to dropping knowledge about the subquery's sort
ordering, but I believe it's okay, because any sort key that the
outer query actually has any interest in would appear in the
reltarget list.
This second issue is of very long standing, but right now there's no
evidence that it causes observable problems before 9.6, so I refrained
from back-patching further than that. We can revisit that choice if
somebody finds a way to make it cause problems in older branches.
(Developing useful test cases for these issues is really problematic;
fixing convert_subquery_pathkeys removes the only known way to exhibit
the create_merge_append_plan bug, and neither of the test cases added
by this patch causes a problem in all branches, even when considering
the issues separately.)
The second issue explains bug #15795 from Suresh Kumar R ("could not
find pathkey item to sort" with nested DISTINCT queries). I stumbled
across the first issue while investigating that.
Discussion: https://postgr.es/m/15795-fadb56c8e44ee73c@postgresql.org
When running a batch of VACUUM or ANALYZE commands on a given database,
there were cases where it is possible to have vacuumdb not report an
error where it actually should, leading to incorrect status results.
Author: Julien Rouhaud
Reviewed-by: Amit Kapila, Michael Paquier
Discussion: https://postgr.es/m/CAOBaU_ZuTwz7CtqLYJ1Ouuh272bTQPLN8b1bAPk0bCBm4PDMTQ@mail.gmail.com
Backpatch-through: 9.5
Previously it's documented that use of replication functions is
restricted to superusers. This is true for the functions which
use replication origin, but not for pg_logicl_emit_message() and
functions which use replication slot. For example, not only
superusers but also users with REPLICATION privilege is allowed
to use the functions for replication slot. This commit fixes
the documentation for the privileges required for those replication
functions.
Back-patch to 9.4 (all supported versions).
Author: Matsumura Ryo
Discussion: https://postgr.es/m/03040DFF97E6E54E88D3BFEE5F5480F74ABA6E16@G01JPEXMBYT04
Commit c0985099, later adjusted by commit 4ab02e81, probed 0.0.0.0
in addition to 127.0.0.1, for the benefit of Windows build farm
animals. It isn't really useful on Unix systems, and turned out to
be a bit inconvenient to users of some corporate firewall software.
Switch back to probing just 127.0.0.1 on non-Windows systems.
Back-patch to 9.6, like the earlier changes.
Discussion: https://postgr.es/m/CA%2BhUKG%2B21EPwfgs4m%2BtqyRtbVqkOUvP8QQ8sWk9%2Bh55Aub1H3A%40mail.gmail.com
