Commit Graph

45168 Commits

Author SHA1 Message Date
Tom Lane ec4719cd15 Fix partial aggregation for variance(int4) and related aggregates.
A typo in numeric_poly_combine caused bogus results for queries using
it, but of course would only manifest if parallel aggregation is
performed.  Reported by Rajkumar Raghuwanshi.

David Rowley did the diagnosis and the fix; I editorialized rather
heavily on his regression test additions.

Back-patch to v10 where the breakage was introduced (by 9cca11c91).

Discussion: https://postgr.es/m/CAKcux6nU4E2x8nkSBpLOT2DPvQ5LviJ3SGyAN6Sz7qDH4G4+Pw@mail.gmail.com
2018-06-21 16:18:39 -04:00
Alvaro Herrera e474c2b7e4 Set correct context for XPath evaluation
According to the SQL standard, the context of XMLTABLE's XPath
row_expression is the document node of the XML input document, not the
root node.  This becomes visible when a relative path rather than
absolute is used as row expression.  Absolute paths is what was used in
original tests and docs (and the most common form used in examples
throughout the interwebs), which explains why this wasn't noticed
before.

Other functions such as xpath() and xpath_exists() also have this
problem.  While not specified by the SQL standard, it would be pretty
odd to leave those functions to behave differently than XMLTABLE, so
change them too.  However, this is a backwards-incompatible change.

No backpatch, out of fear of breaking code depending on the original
broken behavior.

Author: Markus Winand
Reported-By: Markus Winand
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/0684A598-002C-42A2-AE12-F024A324EAE4@winand.at
2018-06-21 15:56:11 -04:00
Tom Lane 425b4c082c Improve requirements documentation for ldap test suite.
Text by me; data contributed by me, Thomas Munro, Michael Paquier.

Discussion: https://postgr.es/m/20180521013425.GA4476@paquier.xyz
2018-06-21 12:37:21 -04:00
Tom Lane 07e5a21352 Fix mishandling of sortgroupref labels while splitting SRF targetlists.
split_pathtarget_at_srfs() neglected to worry about sortgroupref labels
in the intermediate PathTargets it constructs.  I think we'd supposed
that their labeling didn't matter, but it does at least for the case that
GroupAggregate/GatherMerge nodes appear immediately under the ProjectSet
step(s).  This results in "ERROR: ORDER/GROUP BY expression not found in
targetlist" during create_plan(), as reported by Rajkumar Raghuwanshi.

To fix, make this logic track the sortgroupref labeling of expressions,
not just their contents.  This also restores the pre-v10 behavior that
separate GROUP BY expressions will be kept distinct even if they are
textually equal().

Discussion: https://postgr.es/m/CAKcux6=1_Ye9kx8YLBPmJs_xE72PPc6vNi5q2AOHowMaCWjJ2w@mail.gmail.com
2018-06-21 10:58:42 -04:00
Alexander Korotkov bee6a683a5 Improve wording of release notes item
PostgreSQL 11 introduces compress method for SP-GiST opclasses.  That
was mistakenly interpreted as compression support for SP-GiST while
actually that allows lossy representation of leaf keys.

Author: Alexander Korotkov, based on proposal by Darafei Praliaskouski
Discussion: https://postgr.es/m/CAC8Q8tKbYmNdiyWr7hE4GfMY4fbqHKkFziKgrUuWHH6HJQs3og%40mail.gmail.com
2018-06-21 15:49:19 +03:00
Alvaro Herrera 9cd929d360 Update expected XML output with disabled XML
Should have been done in previous commit.
2018-06-20 13:05:44 -04:00
Alvaro Herrera b7f0be9a7e Accept TEXT and CDATA nodes in XMLTABLE's column_expression.
Column expressions that match TEXT or CDATA nodes must return the
contents of the nodes themselves, not the content of non-existing
children (i.e. the empty string).

Author: Markus Winand
Reported-by: Markus Winand
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/0684A598-002C-42A2-AE12-F024A324EAE4@winand.at
2018-06-20 12:58:12 -04:00
Magnus Hagander 3adcad4558 Add missing include
Per buildfarm
2018-06-20 18:19:35 +02:00
Alvaro Herrera 8f97af60d1 Consistently use the term 'partitioned rel' in partprune comments
We were using 'partition rel' in a few places, which is quite confusing.

Author: Amit Langote
Reviewed-by: David Rowley
Reviewed-by: Michaël Paquier
Discussion: https://postgr.es/m/fd256561-31a2-4b7e-cd84-d8241e7ebc3f@lab.ntt.co.jp
2018-06-20 11:43:01 -04:00
Magnus Hagander 74cfbc8efd Fix typo
Reported using the website comment form
2018-06-20 16:06:03 +02:00
Magnus Hagander d9443d9608 Fix a number of typos
Author: Liudmila Mantrova <l.mantrova@postgrespro.ru>
2018-06-20 16:01:18 +02:00
Magnus Hagander 741ee9dc81 Support long option for --pgdata in pg_verify_checksums
Author: Daniel Gustafsson <daniel@yesql.se>
2018-06-20 14:33:48 +02:00
Magnus Hagander d73300a286 Document the -D and $PGDATA switch/env for pg_verify_checksums
Author: Daniel Gustafsson <daniel@yesql.se>
2018-06-20 14:32:51 +02:00
Magnus Hagander b92ef305c3 Move pg_verify_checksum docs to Server utils
Author: Daniel Gustafsson <daniel@yesql.se>
2018-06-20 14:28:56 +02:00
Amit Kapila 403318b71f Don't consider parallel append for parallel unsafe paths.
Commit ab72716778 allowed Parallel Append paths to be generated for a
relation that is not parallel safe.  Prevent that from happening.

Initial analysis by Tom Lane.

Reported-by: Rajkumar Raghuwanshi
Author: Amit Kapila and Rajkumar Raghuwanshi
Reviewed-by: Amit Khandekar and Robert Haas
Discussion:https://postgr.es/m/CAKcux6=tPJ6nJ08r__nU_pmLQiC0xY15Fn0HvG1Cprsjdd9s_Q@mail.gmail.com
2018-06-20 07:51:42 +05:30
Michael Paquier 1c7c317cd9 Clarify use of temporary tables within partition trees
Since their introduction, partition trees have been a bit lossy
regarding temporary relations.  Inheritance trees respect the following
patterns:
1) a child relation can be temporary if the parent is permanent.
2) a child relation can be temporary if the parent is temporary.
3) a child relation cannot be permanent if the parent is temporary.
4) The use of temporary relations also imply that when both parent and
child need to be from the same sessions.

Partitions share many similar patterns with inheritance, however the
handling of the partition bounds make the situation a bit tricky for
case 1) as the partition code bases a lot of its lookup code upon
PartitionDesc which does not really look after relpersistence.  This
causes for example a temporary partition created by session A to be
visible by another session B, preventing this session B to create an
extra partition which overlaps with the temporary one created by A with
a non-intuitive error message.  There could be use-cases where mixing
permanent partitioned tables with temporary partitions make sense, but
that would be a new feature.  Partitions respect 2), 3) and 4) already.

It is a bit depressing to see those error checks happening in
MergeAttributes() whose purpose is different, but that's left as future
refactoring work.

Back-patch down to 10, which is where partitioning has been introduced,
except that default partitions do not apply there.  Documentation also
includes limitations related to the use of temporary tables with
partition trees.

Reported-by: David Rowley
Author: Amit Langote, Michael Paquier
Reviewed-by: Ashutosh Bapat, Amit Langote, Michael Paquier
Discussion: https://postgr.es/m/CAKJS1f94Ojk0og9GMkRHGt8wHTW=ijq5KzJKuoBoqWLwSVwGmw@mail.gmail.com
2018-06-20 10:42:25 +09:00
Tom Lane c992dca26e Clarify the README files for the various separate TAP-based test suites.
Explain the difference between "make check" and "make installcheck".
Mention the need for --enable-tap-tests (only some of these did so
before).  Standardize their wording about how to run the tests.
2018-06-19 19:30:50 -04:00
Bruce Momjian 9bab9cb36a README: add URLs for openldap installation
Reported-by: Michael Paquier

Discussion: https://postgr.es/m/20180521013425.GA4476@paquier.xyz

Backpatch-through: head
2018-06-19 15:52:17 -04:00
Bruce Momjian 87a19eb9bf doc: explain use of json_populate_record{set}()
The set-returning nature of these functions make their use unclear. The
modified paragraph was added in PG 9.4.

Reported-by: yshaladi@denodo.com

Discussion:  https://postgr.es/m/152571684246.9460.18059951267371255159@wrigleys.postgresql.org

Backpatch-through: 9.4
2018-06-19 13:43:40 -04:00
Alexander Korotkov fb6accd27b Fix typos in release notes
Author: Daniel Gustafsson
Discussion: https://postgr.es/m/8E8CF1F8-BCB2-4D86-A059-4BF5138F6D87%40yesql.se
2018-06-19 18:32:20 +03:00
Michael Paquier bde64eb610 Track new configure flags introduced for version 11 in pg_config.h.win32
The following set of flags mainly matter when building Postgres code
with MSVC and those have been forgotten with latest developments:
- HAVE_LDAP_INITIALIZE, added by 35c0754f, and marked as disabled.
ldap_initialize() is a non-standard extension that provides a way to use
"ldaps" with OpenLDAP, but it is not supported on Windows, and instead
the non-standard ldap_sslinit() is used if WIN32 is defined.  Per input
from Thomas Munro.
- HAVE_X509_GET_SIGNATURE_NID, added by 054e8c6c, which is used by
SCRAM's channel binding tls-server-end-point.  Having this flag disabled
would cause this channel binding type to be unsupported for Windows
builds.
- HAVE_SSL_CLEAR_OPTIONS, added recently as of a364dfa4 to disable SSL
compression.
- HAVE_ASN1_STRING_GET0_DATA, added by 5c6df67, which is used to track
a new compatibility with OpenSSL 1.1.0.  This was missing from
pg_config.win32.h and is not enabled by default.  HAVE_BIO_GET_DATA,
HAVE_OPENSSL_INIT_SSL and HAVE_BIO_METH_NEW gain the same treatment.

The second and third flags are enabled with this commit, which raises
the bar of OpenSSL support to 1.0.2 on Windows as a minimum.  As this
is the LTS (long-time support) version of OpenSSL community and knowing
that all recent installers referred by OpenSSL upstream don't have
anymore 1.0.1 or older, we could live with that requirement.  In order
to allow the code to compile with OpenSSL 1.1.0, all the flags mentioned
above need to be enabled in pg_config.h.win32.

Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/20180529211559.GF6632@paquier.xyz
2018-06-19 09:00:33 +09:00
Tom Lane 93b6e03ab4 Fix jsonb_plperl to convert Perl UV values correctly.
Values greater than IV_MAX were incorrectly converted to SQL,
for instance ~0 would become -1 rather than 18446744073709551615
(on a 64-bit machine).

Dagfinn Ilmari Mannsåker, adjusted a bit by me

Discussion: https://postgr.es/m/d8jtvskjzzs.fsf@dalvik.ping.uio.no
2018-06-18 17:39:57 -04:00
Tom Lane e3b7f7cc50 Fix contrib/hstore_plperl to look through scalar refs.
Bring this transform function into sync with the policy established
by commit 3a382983d.

Also, fix it to make sure that what it drills down to is indeed a
hash, and not some other kind of Perl SV.  Previously, the test
cases added here provoked crashes.

Because of the crash hazard, back-patch to 9.5 where this module
was introduced.

Discussion: https://postgr.es/m/28336.1528393969@sss.pgh.pa.us
2018-06-18 15:55:06 -04:00
Tom Lane 3a382983d1 Allow plperl_sv_to_datum to look through scalar refs.
There seems little reason for the policy of throwing error if we
find a ref to something other than a hash or array.   Recursively
look through the ref, instead.  This makes the behavior in non-transform
cases comparable to what was already instantiated for jsonb_plperl.

Note that because we invoke any available transform function before
considering the ref case, it's up to each transform function whether
it wants to play along with this behavior or do something different.

Because the previous behavior was just to throw a useless error,
this seems unlikely to create any compatibility issues.  Still, given
the lack of field complaints so far, seems best not to back-patch.

Discussion: https://postgr.es/m/28336.1528393969@sss.pgh.pa.us
2018-06-18 15:31:57 -04:00
Tom Lane e4300a3552 Avoid platform-dependent output from Data::Dumper.
Per buildfarm, the output from Data::Dumper for an IEEE infinity
is platform-dependent (e.g. "inf" vs "Inf").  Just skip that one
test case in the plperlu test; testing it on the plperl side is
coverage enough.  Fixes issue in commit 1731e3741.
2018-06-18 14:53:21 -04:00
Tom Lane 1731e3741c Fix excessive enreferencing in jsonb-to-plperl transform.
We want, say, 2 to be transformed as 2, not \\2 which is what the
original coding produced.  Perl's standard seems to be to add an RV
wrapper only for hash and array SVs, so do it like that.

This was missed originally because the test cases only checked what came
out of a round trip back to SQL, and the strip-all-dereferences loop at
the top of SV_to_JsonbValue hides the extra refs from view.  As a better
test, print the Perl value with Data::Dumper, like the hstore_plperlu
tests do.  While we can't do that in the plperl test, only plperlu,
that should be good enough because this code is the same for both PLs.
But also add a simplistic test for extra REFs, which we can do in both.

That strip-all-dereferences behavior is now a bit dubious; it's unlike
what happens for other Perl-to-SQL conversions.  However, the best
thing to do seems to be to leave it alone and make the other conversions
act similarly.  That will be done separately.

Dagfinn Ilmari Mannsåker, adjusted a bit by me

Discussion: https://postgr.es/m/d8jlgbq66t9.fsf@dalvik.ping.uio.no
2018-06-18 14:31:42 -04:00
Tom Lane 45e98ee730 Remove obsolete prohibition on function name matching a column name.
ProcedureCreate formerly threw an error if the function to be created
has one argument of composite type and the function name matches some
column of the composite type.  This was a (very non-bulletproof) defense
against creating situations where f(x) and x.f are ambiguous.  But we
don't really need such a defense in the wake of commit b97a3465d, which
allows us to deal with such situations fairly cleanly.  This behavior
also created a dump-and-reload hazard, since a function might be
rejected if a conflicting column name had been added to the input
composite type later.  Hence, let's just drop the check.

Discussion: https://postgr.es/m/CAOW5sYa3Wp7KozCuzjOdw6PiOYPi6D=VvRybtH2S=2C0SVmRmA@mail.gmail.com
2018-06-18 11:57:33 -04:00
Tom Lane b97a3465d7 Consider syntactic form when disambiguating function vs column reference.
Postgres has traditionally considered the syntactic forms f(x) and x.f
to be equivalent, allowing tricks such as writing a function and then
using it as though it were a computed-on-demand column.  However, our
behavior when both interpretations are feasible left something to be
desired: we always chose the column interpretation.  This could lead
to very surprising results, as in a recent bug report from Neil Conway.
It also created a dump-and-reload hazard, since what was a function
call in a dumped view could get interpreted as a column reference
at reload, if a matching column name had been added to the underlying
table since the view was created.

What seems better, in ambiguous situations, is to prefer the choice
matching the syntactic form of the reference.  This seems much less
astonishing in general, and it fixes the dump/reload hazard.

Although this could be called a bug fix, there have been few complaints
and there's some small risk of breaking applications that depend on the
old behavior, so no back-patch.  It does seem reasonable to slip it
into v11, though.

Discussion: https://postgr.es/m/CAOW5sYa3Wp7KozCuzjOdw6PiOYPi6D=VvRybtH2S=2C0SVmRmA@mail.gmail.com
2018-06-18 11:39:33 -04:00
Thomas Munro 4c8156d871 Add PGTYPESchar_free() to avoid cross-module problems on Windows.
On Windows, it is sometimes important for corresponding malloc() and
free() calls to be made from the same DLL, since some build options can
result in multiple allocators being active at the same time.  For that
reason we already provided PQfreemem().  This commit adds a similar
function for freeing string results allocated by the pgtypes library.

Author: Takayuki Tsunakawa
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8AD5D6%40G01JPEXMBYT05
2018-06-18 18:33:53 +12:00
Michael Paquier 70b4f82a4b Prevent hard failures of standbys caused by recycled WAL segments
When a standby's WAL receiver stops reading WAL from a WAL stream, it
writes data to the current WAL segment without having priorily zero'ed
the page currently written to, which can cause the WAL reader to read
junk data from a past recycled segment and then it would try to get a
record from it.  While sanity checks in place provide most of the
protection needed, in some rare circumstances, with chances increasing
when a record header crosses a page boundary, then the startup process
could fail violently on an allocation failure, as follows:
FATAL:  invalid memory alloc request size XXX

This is confusing for the user and also unhelpful as this requires in
the worst case a manual restart of the instance, impacting potentially
the availability of the cluster, and this also makes WAL data look like
it is in a corrupted state.

The chances of seeing failures are higher if the connection between the
standby and its root node is unstable, causing WAL pages to be written
in the middle.  A couple of approaches have been discussed, like
zero-ing  new WAL pages within the WAL receiver itself but this has the
disadvantage of impacting performance of any existing instances as this
breaks the sequential writes done by the WAL receiver.  This commit
deals with the problem with a more simple approach, which has no
performance impact without reducing the detection of the problem: if a
record is found with a length higher than 1GB for backends, then do not
try any allocation and report a soft failure which will force the
standby to retry reading WAL.  It could be possible that the allocation
call passes and that an unnecessary amount of memory is allocated,
however follow-up checks on records would just fail, making this
allocation short-lived anyway.

This patch owes a great deal to Tsunakawa Takayuki for reporting the
failure first, and then discussing a couple of potential approaches to
the problem.

Backpatch down to 9.5, which is where palloc_extended has been
introduced.

Reported-by: Tsunakawa Takayuki
Reviewed-by: Tsunakawa Takayuki
Author: Michael Paquier
Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8B57AD@G01JPEXMBYT05
2018-06-18 10:43:27 +09:00
Tom Lane 9b53d96684 Suppress -Wshift-negative-value warnings.
Clean up four places that result in compiler warnings when using recent
gcc with this warning class enabled (as seen on buildfarm members
calliphoridae, skink, and others).  In all these places, this is purely
cosmetic, because the shift distance could not be large enough to risk
a change of sign, so there's no chance of implementation-dependent
behavior.  Still, it's easy enough to avoid the warning by casting the
shifted value to unsigned, so let's do that.

Patch HEAD only, this isn't worth a back-patch.
2018-06-17 16:15:11 -04:00
Peter Geoghegan 514d4a1338 Remove INCLUDE attributes section from docs.
Discussing covering indexes in a chapter that is mostly about the
behavior of B-Tree operator classes is unnecessary.  The CREATE INDEX
documentation's handling of covering indexes seems sufficient.

Discussion: https://postgr.es/m/CAH2-WzmpU=L_6VjhhOAMfoyHLr-pZd1kDc+jpa3c3a8EOmtcXA@mail.gmail.com
2018-06-16 15:28:50 -07:00
Tom Lane e716585235 Use -Wno-format-truncation and -Wno-stringop-truncation, if available.
gcc 8 has started emitting some warnings that are largely useless for
our purposes, particularly since they complain about code following
the project-standard coding convention that path names are assumed
to be shorter than MAXPGPATH.  Even if we make the effort to remove
that assumption in some future release, the changes wouldn't get
back-patched.  Hence, just suppress these warnings, on compilers that
have these switches.

Backpatch to all supported branches.

Discussion: https://postgr.es/m/1524563856.26306.9.camel@gunduz.org
2018-06-16 15:34:07 -04:00
Tom Lane 6b74f5eaad Avoid unnecessary use of strncpy in a couple of places in ecpg.
Use of strncpy with a length limit based on the source, rather than
the destination, is non-idiomatic and draws warnings from gcc 8.
Replace with memcpy, which does exactly the same thing in these cases,
but with less chance for confusion.

Backpatch to all supported branches.

Discussion: https://postgr.es/m/21789.1529170195@sss.pgh.pa.us
2018-06-16 14:58:11 -04:00
Tom Lane 5d923eb29b Use snprintf not sprintf in pg_waldump's timestamptz_to_str.
This could only cause an issue if strftime returned a ridiculously
long timezone name, which seems unlikely; and it wouldn't qualify
as a security problem even then, since pg_waldump (nee pg_xlogdump)
is a debug tool not part of the server.  But gcc 8 has started issuing
warnings about it, so let's use snprintf and be safe.

Backpatch to 9.3 where this code was added.

Discussion: https://postgr.es/m/21789.1529170195@sss.pgh.pa.us
2018-06-16 14:45:47 -04:00
Tom Lane 0dcf68e5a1 Fix some minor error-checking oversights in ParseFuncOrColumn().
Recent additions to ParseFuncOrColumn to make it reject non-procedure
functions in CALL were neither adequate nor documented.  Reorganize
the code to ensure uniform results for all the cases that should be
rejected.  Also, use ERRCODE_WRONG_OBJECT_TYPE for this case as well
as the converse case of a procedure in a non-CALL context.  The
original coding used ERRCODE_UNDEFINED_FUNCTION which seems wrong,
and is certainly inconsistent with the adjacent wrong-kind-of-routine
errors.

This reorganization also causes the checks for aggregate decoration with
a non-aggregate function to be made in the FUNCDETAIL_COERCION case;
that they were not is a long-standing oversight.

Discussion: https://postgr.es/m/14497.1529089235@sss.pgh.pa.us
2018-06-16 14:11:14 -04:00
Simon Riggs 15378c1a15 Remove AELs from subxids correctly on standby
Issues relate only to subtransactions that hold AccessExclusiveLocks
when replayed on standby.

Prior to PG10, aborting subtransactions that held an
AccessExclusiveLock failed to release the lock until top level commit or
abort. 49bff5300d fixed that.

However, 49bff5300d also introduced a similar bug where subtransaction
commit would fail to release an AccessExclusiveLock, leaving the lock to
be removed sometimes early and sometimes late. This commit fixes
that bug also. Backpatch to PG10 needed.

Tested by observation. Note need for multi-node isolationtester to improve
test coverage for this and other HS cases.

Reported-by: Simon Riggs
Author: Simon Riggs
2018-06-16 14:03:29 +01:00
Tatsuo Ishii 1cfdb1cb0e Fix memory leak in BufFileCreateShared().
Also this commit unifies some duplicated code in makeBufFile() and
BufFileOpenShared() into new function makeBufFileCommon().

Author: Antonin Houska
Reviewed-By: Thomas Munro, Tatsuo Ishii
Discussion: https://postgr.es/m/16139.1529049566%40localhost
2018-06-16 14:21:08 +09:00
Alvaro Herrera ff03112bdc Fix off-by-one bug in XactLogCommitRecord
Commit 1eb6d6527a introduced zeroed alignment bytes in the GID field
of commit/abort WAL records.  Fixup commit cf5a189059 later changed
that representation into a regular cstring with a single terminating
zero byte, but it also introduced an off-by-one mistake.  Fix that.

Author: Nikhil Sontakke
Reported-by: Nikhil Sontakke
Discussion: https://postgr.es/m/CAMGcDxey6dG1DP34_tJMoWPcp5sPJUAL4K5CayUUXLQSx2GQpA@mail.gmail.com
2018-06-15 15:00:41 -04:00
Alexander Korotkov dad8bed04a Fix memory leak in PLySequence_ToJsonbValue()
PyObject returned from PySequence_GetItem() is not released.  Similar code in PLyMapping_ToJsonbValue() is correct, because according to Python documentation
PyList_GetItem() and PyTuple_GetItem() return a borrowed reference while
PySequence_GetItem() returns new reference.  contrib/jsonb_plpython is new
in PostgreSQL 11, no backpatch is needed.

Author: Nikita Glukhov
Discussion: https://postgr.es/m/6001af16-b242-2527-bc7e-84b8a959163b%40postgrespro.ru
2018-06-15 15:01:46 +03:00
Tatsuo Ishii 969274d813 Fix memory leak.
Memory is allocated twice for "file" and "files" variables in
BufFileOpenShared().

Author: Antonin Houska
Discussion: https://postgr.es/m/11329.1529045692%40localhost
2018-06-15 16:32:59 +09:00
Alvaro Herrera 74da7cda31 Fail BRIN control functions during recovery explicitly
They already fail anyway, but prior to this patch they raise an ugly
error message about a lock that cannot be acquired.  This just improves
the message.

Author: Masahiko Sawada
Reported-by: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoBZau4g4_NUf3BKNd=CdYK+xaPdtJCzvOC1TxGdTiJx_Q@mail.gmail.com
Reviewed-by: Kuntal Ghosh, Alexander Korotkov, Simon Riggs, Michaël Paquier, Álvaro Herrera
2018-06-14 12:51:32 -04:00
Simon Riggs dc878ffedf Remove spurious code comments in standby related code
GetRunningTransactionData() suggested that subxids were not worth
optimizing away if overflowed, yet they have already been removed
for that case.

Changes to LogAccessExclusiveLock() API forgot to remove the
prior comment when it was copied to LockAcquire().
2018-06-14 12:17:51 +01:00
Simon Riggs 802bde87ba Remove cut-off bug from RunningTransactionData
32ac7a118f tried to fix a Hot Standby issue
reported by Greg Stark, but in doing so caused
a different bug to appear, noted by Andres Freund.

Revoke the core changes from 32ac7a118f,
leaving in its place a minor change in code
ordering and comments to explain for the future.
2018-06-14 12:02:41 +01:00
Tom Lane 91781335ed Code review for match_clause_to_partition_key().
Fix inconsistent decisions about NOMATCH vs UNSUPPORTED result codes.
If we're going to cater for partkeys that have the same expression and
different collations, surely we should also support partkeys with the
same expression and different opclasses.

Clean up shaky handling of commuted opclauses, eg checking the wrong
operator to see what its negator is.  This wouldn't cause any actual
bugs given a sane opclass definition, but it doesn't seem helpful to
expend more code to be less correct.

Improve handling of null elements in ScalarArrayOp arrays: in the
"op ALL" case, we can conclude they result in an unsatisfiable clause.

Minor cosmetic changes and comment improvements.
2018-06-13 16:10:30 -04:00
Tom Lane 19832753f1 Fix some ill-chosen names for globally-visible partition support functions.
"compute_hash_value" is particularly gratuitously generic, but IMO
all of these ought to have names clearly related to partitioning.
2018-06-13 13:18:02 -04:00
Tom Lane e23bae82cf Fix up run-time partition pruning's use of relcache's partition data.
The previous coding saved pointers into the partitioned table's relcache
entry, but then closed the relcache entry, causing those pointers to
nominally become dangling.  Actual trouble would be seen in the field
only if a relcache flush occurred mid-query, but that's hardly out of
the question.

While we could fix this by copying all the data in question at query
start, it seems better to just hold the relcache entry open for the
whole query.

While at it, improve the handling of support-function lookups: do that
once per query not once per pruning test.  There's still something to be
desired here, in that we fail to exploit the possibility of caching data
across queries in the fn_extra fields of the relcache's FmgrInfo structs,
which could happen if we just used those structs in-place rather than
copying them.  However, combining that with the possibility of per-query
lookups of cross-type comparison functions seems to require changes in the
APIs of a lot of the pruning support functions, so it's too invasive to
consider as part of this patch.  A win would ensue only for complex
partition key data types (e.g. arrays), so it may not be worth the
trouble.

David Rowley and Tom Lane

Discussion: https://postgr.es/m/17850.1528755844@sss.pgh.pa.us
2018-06-13 12:03:26 -04:00
Alexander Korotkov e146e4d02d Documentation improvement for pg_trgm
Documentation of word_similarity() and strict_word_similarity() functions
contains some vague wordings which could confuse users.  This patch makes
those wordings more clear.  word_similarity() was introduced in PostgreSQL 9.6,
and corresponding part of documentation needs to be backpatched.

Author: Bruce Momjian, Alexander Korotkov
Discussion: https://postgr.es/m/20180526165648.GB12510%40momjian.us
Backpatch: 9.6, where word_similarity() was introduced
2018-06-13 18:23:00 +03:00
Andrew Dunstan e3eb8be77e Exclude files in .git from list of perl files
The .git directory might contain perl files, as hooks, for example.
Since we have no control over these they should be excluded from things
like our perlcritic checks.

Per offline report from Mike Blackwell.
2018-06-12 14:54:43 -04:00
Andres Freund a54e1f1587 Fix bugs in vacuum of shared rels, by keeping their relcache entries current.
When vacuum processes a relation it uses the corresponding relcache
entry's relfrozenxid / relminmxid as a cutoff for when to remove
tuples etc. Unfortunately for nailed relations (i.e. critical system
catalogs) bugs could frequently lead to the corresponding relcache
entry being stale.

This set of bugs could cause actual data corruption as vacuum would
potentially not remove the correct row versions, potentially reviving
them at a later point.  After 699bf7d05c some corruptions in this vein
were prevented, but the additional error checks could also trigger
spuriously. Examples of such errors are:
  ERROR: found xmin ... from before relfrozenxid ...
and
  ERROR: found multixact ... from before relminmxid ...
To be caused by this bug the errors have to occur on system catalog
tables.

The two bugs are:

1) Invalidations for nailed relations were ignored, based on the
   theory that the relcache entry for such tables doesn't
   change. Which is largely true, except for fields like relfrozenxid
   etc.  This means that changes to relations vacuumed in other
   sessions weren't picked up by already existing sessions.  Luckily
   autovacuum doesn't have particularly longrunning sessions.

2) For shared *and* nailed relations, the shared relcache init file
   was never invalidated while running.  That means that for such
   tables (e.g. pg_authid, pg_database) it's not just already existing
   sessions that are affected, but even new connections are as well.
   That explains why the reports usually were about pg_authid et. al.

To fix 1), revalidate the rd_rel portion of a relcache entry when
invalid. This implies a bit of extra complexity to deal with
bootstrapping, but it's not too bad.  The fix for 2) is simpler,
simply always remove both the shared and local init files.

Author: Andres Freund
Reviewed-By: Alvaro Herrera
Discussion:
    https://postgr.es/m/20180525203736.crkbg36muzxrjj5e@alap3.anarazel.de
    https://postgr.es/m/CAMa1XUhKSJd98JW4o9StWPrfS=11bPgG+_GDMxe25TvUY4Sugg@mail.gmail.com
    https://postgr.es/m/CAKMFJucqbuoDRfxPDX39WhA3vJyxweRg_zDVXzncr6+5wOguWA@mail.gmail.com
    https://postgr.es/m/CAGewt-ujGpMLQ09gXcUFMZaZsGJC98VXHEFbF-tpPB0fB13K+A@mail.gmail.com
Backpatch: 9.3-
2018-06-12 11:13:21 -07:00