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43831 Commits

Author SHA1 Message Date
Alvaro Herrera
7acbb481c8 Reduce cost of test_decoding's new oldest_xmin test
Change a whole-database VACUUM into doing just pg_attribute, which is
the portion that verifies what we want it to do.  The original
formulation wastes a lot of CPU time, which leads the test to fail when
runtime exceeds isolationtester timeout when it's super-slow, such as
under CLOBBER_CACHE_ALWAYS.  Per buildfarm member friarbird.

It turns out that the previous shape of the test doesn't always detect
the condition it is supposed to detect (on unpatched reorderbuffer
code): the reason is that there is a good chance of encountering a
xl_running_xacts record (logged every 15 seconds) before the checkpoint
-- and because we advance the xmin when we receive that WAL record, and
we *don't* advance the xmin twice consecutively without receiving a
client message in between, that means the xmin is not advanced enough
for the tuple to be pruned from pg_attribute by VACUUM.  So the test
would spuriously pass.

The reason this test deficiency wasn't detected earlier is that HOT
pruning removes the tuple anyway, even if vacuum leaves it in place, so
the test correctly fails (detecting the coding mistake), but for the
wrong reason.

To fix this mess, run the s0_get_changes step twice before vacuum
instead of once: this seems to cause the xmin to be advanced reliably,
wreaking havoc with more certainty.

Author: Arseny Sher
Discussion: https://postgr.es/m/87h8lkuxoa.fsf@ars-thinkpad
2018-07-05 16:58:30 -04:00
Peter Eisentraut
b1def471d5 doc: Fix typos
Author: Justin Pryzby <pryzby@telsasoft.com>
2018-07-05 22:52:19 +02:00
Peter Eisentraut
fbbe29ba66 Fix typo 2018-07-05 08:20:15 +02:00
Peter Eisentraut
a1974349bd doc: Improve wording and fix whitespace 2018-07-05 08:20:15 +02:00
Michael Paquier
6716f2f962 Prevent references to invalid relation pages after fresh promotion
If a standby crashes after promotion before having completed its first
post-recovery checkpoint, then the minimal recovery point which marks
the LSN position where the cluster is able to reach consistency may be
set to a position older than the first end-of-recovery checkpoint while
all the WAL available should be replayed.  This leads to the instance
thinking that it contains inconsistent pages, causing a PANIC and a hard
instance crash even if all the WAL available has not been replayed for
certain sets of records replayed.  When in crash recovery,
minRecoveryPoint is expected to always be set to InvalidXLogRecPtr,
which forces the recovery to replay all the WAL available, so this
commit makes sure that the local copy of minRecoveryPoint from the
control file is initialized properly and stays as it is while crash
recovery is performed.  Once switching to archive recovery or if crash
recovery finishes, then the local copy minRecoveryPoint can be safely
updated.

Pavan Deolasee has reported and diagnosed the failure in the first
place, and the base fix idea to rely on the local copy of
minRecoveryPoint comes from Kyotaro Horiguchi, which has been expanded
into a full-fledged patch by me.  The test included in this commit has
been written by Álvaro Herrera and Pavan Deolasee, which I have modified
to make it faster and more reliable with sleep phases.

Backpatch down to all supported versions where the bug appears, aka 9.3
which is where the end-of-recovery checkpoint is not run by the startup
process anymore.  The test gets easily supported down to 10, still it
has been tested on all branches.

Reported-by: Pavan Deolasee
Diagnosed-by: Pavan Deolasee
Reviewed-by: Pavan Deolasee, Kyotaro Horiguchi
Author: Michael Paquier, Kyotaro Horiguchi, Pavan Deolasee, Álvaro
Herrera
Discussion: https://postgr.es/m/CABOikdPOewjNL=05K5CbNMxnNtXnQjhTx2F--4p4ruorCjukbA@mail.gmail.com
2018-07-05 10:47:01 +09:00
Andres Freund
0095809890 Check for interrupts inside the nbtree page deletion code.
When deleting pages the nbtree code has to walk through siblings of a
tree node. When those sibling links are corrupted that can lead to
endless loops - which are currently not interruptible.  This is
especially problematic if autovacuum is repeatedly blocked on such
indexes, as it can be hard to get out of that situation without
resorting to single user mode.

Thus add interrupt checks to appropriate places in such
loops. Unfortunately in one of the cases it's it's not easy to do so.

Between 9.3 and 9.4 the page deletion (and page split) code changed
significantly. Before it was significantly less robust against
interruptions. Therefore don't backpatch to 9.3.

Author: Andres Freund
Discussion: https://postgr.es/m/20180627191629.wkunw2qbibnvlz53@alap3.anarazel.de
Backpatch: 9.4-
2018-07-04 14:58:39 -07:00
Fujii Masao
8463be060d Improve the performance of relation deletes during recovery.
When multiple relations are deleted at the same transaction,
the files of those relations are deleted by one call to smgrdounlinkall(),
which leads to scan whole shared_buffers only one time. OTOH,
previously, during recovery, smgrdounlink() (not smgrdounlinkall()) was
called for each file to delete, which led to scan shared_buffers
multiple times. Obviously this could cause to increase the WAL replay
time very much especially when shared_buffers was huge.

To alleviate this situation, this commit changes the recovery so that
it also calls smgrdounlinkall() only one time to delete multiple
relation files.

This is just fix for oversight of commit 279628a0a7, not new feature.
So, per discussion on pgsql-hackers, we concluded to backpatch this
to all supported versions.

Author: Fujii Masao
Reviewed-by: Michael Paquier, Andres Freund, Thomas Munro, Kyotaro Horiguchi, Takayuki Tsunakawa
Discussion: https://postgr.es/m/CAHGQGwHVQkdfDqtvGVkty+19cQakAydXn1etGND3X0PHbZ3+6w@mail.gmail.com
2018-07-05 02:26:22 +09:00
Peter Eisentraut
c2c69d43ad Fix libpq example programs
When these programs call pg_catalog.set_config, they need to check for
PGRES_TUPLES_OK instead of PGRES_COMMAND_OK.  Fix for
5770172cb0c9df9e6ce27c507b449557e5b45124.

Reported-by: Ideriha, Takeshi <ideriha.takeshi@jp.fujitsu.com>
2018-07-01 14:09:03 +02:00
Michael Paquier
b241c119b7 Replace search.cpan.org with metacpan.org
search.cpan.org has been EOL'd, with metacpan.org being the official
replacement to which URLs now redirect.  Update links to match the new
URL. Also update links to CPAN to use https as it will redirect from
http.

Author: Daniel Gustafsson
Discussion: https://postgr.es/m/B74C0219-6BA9-46E1-A524-5B9E8CD3BDB3@yesql.se
2018-06-29 22:17:37 +09:00
Bruce Momjian
5b0539aba9 doc: backpatch mention use of cross platform logical replication
Backpatch 21c1f0c607f0344ae8f71ecaae1fe6f58cf7ff9a to PG 10 docs.

Reported-by: Haribabu Kommi

Discussion: https://postgr.es/m/CAJrrPGfdknoqZcMipPy8XnH3hO3uRic6JTD=jv35oj1DWqL07g@mail.gmail.com

Backpatch-through: only 10
2018-06-28 09:12:07 -04:00
Amit Kapila
5521e3bd5f Fix thinko in comments.
A slot can not be stored in a tuple but it's vice versa.

Reported-by: Ashutosh Bapat
Author: Ashutosh Bapat
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAFjFpRcHhNhXdegyJv3KKDWrwO1_NB_KYZM_ZSDeMOZaL1A5jQ@mail.gmail.com
2018-06-27 18:29:42 +05:30
Alvaro Herrera
b767b3f2e5 Fix "base" snapshot handling in logical decoding
Two closely related bugs are fixed.  First, xmin of logical slots was
advanced too early.  During xl_running_xacts processing, xmin of the
slot was set to the oldest running xid in the record, but that's wrong:
actually, snapshots which will be used for not-yet-replayed transactions
might consider older txns as running too, so we need to keep xmin back
for them.  The problem wasn't noticed earlier because DDL which allows
to delete tuple (set xmax) while some another not-yet-committed
transaction looks at it is pretty rare, if not unique: e.g. all forms of
ALTER TABLE which change schema acquire ACCESS EXCLUSIVE lock
conflicting with any inserts. The included test case (test_decoding's
oldest_xmin) uses ALTER of a composite type, which doesn't have such
interlocking.

To deal with this, we must be able to quickly retrieve oldest xmin
(oldest running xid among all assigned snapshots) from ReorderBuffer. To
fix, add another list of ReorderBufferTXNs to the reorderbuffer, where
transactions are sorted by base-snapshot-LSN.  This is slightly
different from the existing (sorted by first-LSN) list, because a
transaction can have an earlier LSN but a later Xmin, if its first
record does not obtain an xmin (eg. xl_xact_assignment).  Note this new
list doesn't fully replace the existing txn list: we still need that one
to prevent WAL recycling.

The second issue concerns SnapBuilder snapshots and subtransactions.
SnapBuildDistributeNewCatalogSnapshot never assigned a snapshot to a
transaction that is known to be a subtxn, which is good in the common
case that the top-level transaction already has one (no point in doing
so), but a bug otherwise.  To fix, arrange to transfer the snapshot from
the subtxn to its top-level txn as soon as the kinship gets known.
test_decoding's snapshot_transfer verifies this.

Also, fix a minor memory leak: refcount of toplevel's old base snapshot
was not decremented when the snapshot is transferred from child.

Liberally sprinkle code comments, and rewrite a few existing ones.  This
part is my (Álvaro's) contribution to this commit, as I had to write all
those comments in order to understand the existing code and Arseny's
patch.

Reported-by: Arseny Sher <a.sher@postgrespro.ru>
Diagnosed-by: Arseny Sher <a.sher@postgrespro.ru>
Co-authored-by: Arseny Sher <a.sher@postgrespro.ru>
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://postgr.es/m/87lgdyz1wj.fsf@ars-thinkpad
2018-06-26 16:38:34 -04:00
Fujii Masao
09879f7536 Fix documentation bug related to backup history file.
The backup history file has been no longer necessary for recovery
since the version 9.0. It's now basically just for informational purpose.
But previously the documentations still described that a recovery
requests the backup history file to proceed. The commit fixes this
documentation bug.

Back-patch to all supported versions.

Author: Yugo Nagata
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180626174752.0ce505e3.nagata@sraoss.co.jp
2018-06-27 00:49:47 +09:00
Thomas Munro
3566873f21 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
2018-06-26 19:49:52 +12:00
Thomas Munro
88554c0911 Move RecoveryLockList into a hash table.
Standbys frequently need to release all locks held by a given xid.
Instead of searching one big list linearly, let's create one list
per xid and put them in a hash table, so we can find what we need
in O(1) time.

Earlier analysis and a prototype were done by David Rowley, though
this isn't his patch.

Back-patch all the way.

Author: Thomas Munro
Diagnosed-by: David Rowley, Andres Freund
Reviewed-by: Andres Freund, Tom Lane, Robert Haas
Discussion: https://postgr.es/m/CAEepm%3D1mL0KiQ2KJ4yuPpLGX94a4Ns_W6TL4EGRouxWibu56pA%40mail.gmail.com
Discussion: https://postgr.es/m/CAKJS1f9vJ841HY%3DwonnLVbfkTWGYWdPN72VMxnArcGCjF3SywA%40mail.gmail.com
2018-06-26 17:17:27 +12:00
Michael Paquier
324076a626 Correct handling of fsync failures with tar mode of walmethods.c
This file has been missing the fact that it needs to report back to
callers a proper failure on fsync calls.  I have spotted the one in
tar_finish() while Kuntal has spotted the one in tar_close().

Backpatch down to 10 where this code has been introduced.

Reported by: Michael Paquier, Kuntal Ghosh
Author: Michael Paquier
Reviewed-by: Kuntal Ghosh, Magnus Hagander
Discussion: https://postgr.es/m/20180625024356.GD1146@paquier.xyz
2018-06-26 09:56:55 +09:00
Alvaro Herrera
99fb44357c Update obsolete comments
Commit 9fab40ad32ef removed some pre-allocating logic in
reorderbuffer.c, but left outdated comments in place.  Repair.

Author: Álvaro Herrera
2018-06-25 15:43:05 -04:00
Michael Paquier
6eec6724ff Address set of issues with errno handling
System calls mixed up in error code paths are causing two issues which
several code paths have not correctly handled:
1) For write() calls, sometimes the system may return less bytes than
what has been written without errno being set.  Some paths were careful
enough to consider that case, and assumed that errno should be set to
ENOSPC, other calls missed that.
2) errno generated by a system call is overwritten by other system calls
which may succeed once an error code path is taken, causing what is
reported to the user to be incorrect.

This patch uses the brute-force approach of correcting all those code
paths.  Some refactoring could happen in the future, but this is let as
future work, which is not targeted for back-branches anyway.

Author: Michael Paquier
Reviewed-by: Ashutosh Sharma
Discussion: https://postgr.es/m/20180622061535.GD5215@paquier.xyz
2018-06-25 11:20:19 +09:00
Bruce Momjian
6350dcc1f4 doc: adjust order of NUMERIC arguments to match syntax
Specifically, mention precision before scale

Reported-by: claytonjsalem@gmail.com

Discussion: https://postgr.es/m/152967566691.1268.1062965601465200209@wrigleys.postgresql.org

Backpatch-through: 9.3
2018-06-24 18:07:00 -04:00
Bruce Momjian
c1975c1af7 doc: show how interval's 3 unit buckets behave using EXTRACT()
This clarifies when justify_days() and justify_hours() are useful.
Paragraph moved too.

Reported-by: vodevsh@gmail.com

Discussion: https://postgr.es/m/152698651482.26744.15456677499485530703@wrigleys.postgresql.org

Backpatch-through: 9.3
2018-06-23 23:32:41 -04:00
Alvaro Herrera
b742010890 Disclaim support for default namespace in XMLTABLE
Pavel Stehule's original patch had support for default namespace, but I
ripped it out before commit -- hence the docs were correct when written,
and I broke them by omission :-(.  Remove the offending phrase.

Author: Daniel Gustafsson
Discussion: https://postgr.es/m/1550C5E5-FC70-4493-A226-AA137D831E8D@yesql.se
2018-06-21 17:01:10 -04:00
Tom Lane
b8a1d03020 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 16:18:34 -04:00
Tom Lane
a4c95b0b80 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
Alvaro Herrera
04ab840b84 Update expected XML output with disabled XML, too 2018-06-20 13:02:46 -04:00
Alvaro Herrera
e10bc161f9 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
99ba8d2f8f Fix typo
Reported using the website comment form
2018-06-20 16:07:07 +02:00
Michael Paquier
5862174ec7 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 10:48:28 +09:00
Bruce Momjian
a6fb9378b8 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
Tom Lane
7594b7a533 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
Michael Paquier
fb28104a4b 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 10:43:42 +09:00
Tom Lane
416e3e318c 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
8c92485545 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 14:58:21 -04:00
Tom Lane
1893326158 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
Alvaro Herrera
3b5f4f1f40 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
Alexander Korotkov
476ba1ec98 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 18:32:03 +03:00
Andres Freund
2ce64caaf7 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
Tom Lane
b10edaf4bb Fix access to just-closed relcache entry.
It might be impossible for this to cause a problem in non-debug builds,
since there'd be no opportunity for the relcache entry to get recycled
before the fetch.  It blows up nicely with -DRELCACHE_FORCE_RELEASE plus
valgrind, though.

Evidently introduced by careless refactoring in commit f0e44751d.
Back-patch accordingly.

Discussion: https://postgr.es/m/27543.1528758304@sss.pgh.pa.us
2018-06-11 19:17:50 -04:00
Michael Paquier
858571843c Fix grammar in documentation related to checkpoint_flush_after
Reported-by: Christopher Jones
2018-06-11 09:57:09 +09:00
Michael Paquier
fd73508fd1 Fix grammar in REVOKE documentation
Reported-by: Erwin Brandstetter
2018-06-10 22:48:29 +09:00
Alvaro Herrera
a25c207b2f Teach SHOW ALL to honor pg_read_all_settings membership
Also, fix the pg_settings view to display source filename and line
number when invoked by a pg_read_all_settings member.  This addition by
me (Álvaro).

Also, fix wording of the comment in GetConfigOption regarding the
restriction it implements, renaming the parameter for extra clarity.
Noted by Michaël.

These were all oversight in commit 25fff40798fc; backpatch to pg10,
where that commit first appeared.

Author: Laurenz Albe
Reviewed-by: Michaël Paquier, Álvaro Herrera
Discussion: https://postgr.es/m/1519917758.6586.8.camel@cybertec.at
2018-06-08 16:27:56 -04:00
Peter Eisentraut
6695e956f8 Fix typo 2018-06-08 11:55:25 -04:00
Heikki Linnakangas
0692f29ab7 Fix obsolete comment.
The 'orig_slot' argument was removed in commit c0a8ae7be392, but that
commit forgot to update the comment.

Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/194ac4bf-7b4a-c887-bf26-bc1a85ea995a@lab.ntt.co.jp
2018-06-07 10:02:09 +03:00
Alvaro Herrera
1d5b249310 Fix function code in error report
This bug causes a lseek() failure to be reported as a "could not open"
failure in the error message, muddling bug reports.  I introduced this
copy-and-pasteo in commit 78e122010422.

Noticed while reviewing code for bug report #15221, from lily liang.  In
version 10 the affected function is only used by multixact.c and
commit_ts, and only in corner-case circumstances, neither of which are
involved in the reported bug (a pg_subtrans failure.)

Author: Álvaro Herrera
2018-06-06 14:48:03 -04:00
Alvaro Herrera
b17be5b807 Fix grammar
Reported-by: Pavlo Golub
Author: Michaël Paquier
Discussion: https://postgr.es/m/152741547.20180530101229@cybertec.at
2018-05-30 14:08:51 -04:00
Bruce Momjian
6160ce9a8f doc: mark 'replaceable' parameter for backup program listing
Reported-by: Liudmila Mantrova

Discussion: https://postgr.es/m/f3e2c0f5-5266-d626-58d7-b77e1b29d870@postgrespro.ru

Author: Liudmila Mantrova

Backpatch-through: 9.3
2018-05-28 14:19:45 -04:00
Bruce Momjian
9b5532a3c7 doc: adjust DECLARE docs to mention FOR UPDATE behavior
Reported-by: Peter Eisentraut

Discussion: https://postgr.es/m/8dc63ba7-dc56-fc7c-fc16-4fae03e3bfe6@2ndquadrant.com

Author: Peter Eisentraut, Tom Lane, me

Backpatch-through: 9.3
2018-05-28 13:16:02 -04:00
Tom Lane
5a225b0d61 Fix misidentification of SQL statement type in plpgsql's exec_stmt_execsql.
To distinguish SQL statements that are INSERT/UPDATE/DELETE from other
ones, exec_stmt_execsql looked at the post-rewrite form of the statement
rather than the original.  This is problematic because it did that only
during first execution of the statement (in a session), but the correct
answer could change later due to addition or removal of DO INSTEAD rules
during the session.  That could lead to an Assert failure, as reported
by Tushar Ahuja and Robert Haas.  In non-assert builds, there's a hazard
that we would fail to enforce STRICT behavior when we'd be expected to.
That would happen if an initially present DO INSTEAD, that replaced the
original statement with one of a different type, were removed; after that
the statement should act "normally", including strictness enforcement, but
it didn't.  (The converse case of enforcing strictness when we shouldn't
doesn't seem to be a hazard, as addition of a DO INSTEAD that changes the
statement type would always lead to acting as though the statement returned
zero rows, so that the strictness error could not fire.)

To fix, inspect the original form of the statement not the post-rewrite
form, making it valid to assume the answer can't change intra-session.
This should lead to the same answer in every case except when there is a
DO INSTEAD that changes the statement type; we will now set mod_stmt=true
anyway, while we would not have done so before.  That breaks the Assert
in the SPI_OK_REWRITTEN code path, which expected the latter behavior.
It might be all right to assert mod_stmt rather than !mod_stmt there,
but I'm not entirely convinced that that'd always hold, so just remove
the assertion altogether.

This has been broken for a long time, so back-patch to all supported
branches.

Discussion: https://postgr.es/m/CA+TgmoZUrRN4xvZe_BbBn_Xp0BDwuMEue-0OyF0fJpfvU2Yc7Q@mail.gmail.com
2018-05-25 14:31:06 -04:00
Magnus Hagander
0bf5333714 Remove incorrect statement about IPC configuration on OpenBSD
kern.ipc.shm_use_phys is not a sysctl on OpenBSD, and SEMMAP is not
a kernel configuration option. These were probably copy pasteos from
when the documentation had a single paragraph for *BSD.

Author: Daniel Gustafsson <daniel@yesql.se>
2018-05-25 14:00:37 +02:00
Tom Lane
e8cb8fdfd3 Fix objectaddress.c code for publication relations.
getObjectDescription and getObjectIdentity failed to schema-qualify
the name of the published table, which is bad in getObjectDescription and
unforgivable in getObjectIdentity.  Actually, getObjectIdentity failed to
emit the table's name at all unless "objname" output is requested, which
accidentally works for some (all?) extant callers but is clearly not the
intended API.  Somebody had also not gotten the memo that the output of
getObjectIdentity is not to be translated.

To fix getObjectDescription, I made it call getRelationDescription, which
required refactoring the translatable string for the case, but is more
future-proof in case we ever publish relations that aren't plain tables.
While at it, I made the English output look like "publication of table X
in publication Y"; the added "of" seems to me to make it read much better.

Back-patch to v10 where publications were introduced.

Discussion: https://postgr.es/m/20180522.182020.114074746.horiguchi.kyotaro@lab.ntt.co.jp
2018-05-24 12:38:55 -04:00
Tom Lane
eb1aa1b46b Properly schema-qualify additional object types in getObjectDescription().
Collations, conversions, extended statistics objects (in >= v10),
and all four types of text search objects have schema-qualified names.
getObjectDescription() ignored that and would emit just the base name of
the object, potentially producing wrong or at least highly misleading
output.  Fix it to add the schema name whenever the object is not "visible"
in the current search path, as is the rule for other schema-qualifiable
object types.

Although in common situations the output won't change, this seems to me
(tgl) to be a bug worthy of back-patching, hence do so.

Kyotaro Horiguchi, per a complaint from me

Discussion: https://postgr.es/m/20180522.182020.114074746.horiguchi.kyotaro@lab.ntt.co.jp
2018-05-24 12:07:41 -04:00