Commit Graph

19432 Commits

Author SHA1 Message Date
Tom Lane e03ff73969 Clean up handling of constraint_exclusion and enable_partition_pruning.
The interaction of these parameters was a bit confused/confusing,
and in fact v11 entirely misses the opportunity to apply partition
constraints when a partition is accessed directly (rather than
indirectly from its parent).

In HEAD, establish the principle that enable_partition_pruning controls
partition pruning and nothing else.  When accessing a partition via its
parent, we do partition pruning (if enabled by enable_partition_pruning)
and then there is no need to consider partition constraints in the
constraint_exclusion logic.  When accessing a partition directly, its
partition constraints are applied by the constraint_exclusion logic,
only if constraint_exclusion = on.

In v11, we can't have such a clean division of these GUCs' effects,
partly because we don't want to break compatibility too much in a
released branch, and partly because the clean coding requires
inheritance_planner to have applied partition pruning to a partitioned
target table, which it doesn't in v11.  However, we can tweak things
enough to cover the missed case, which seems like a good idea since
it's potentially a performance regression from v10.  This patch keeps
v11's previous behavior in which enable_partition_pruning overrides
constraint_exclusion for an inherited target table, though.

In HEAD, also teach relation_excluded_by_constraints that it's okay to use
inheritable constraints when trying to prune a traditional inheritance
tree.  This might not be thought worthy of effort given that that feature
is semi-deprecated now, but we have enough infrastructure that it only
takes a couple more lines of code to do it correctly.

Amit Langote and Tom Lane

Discussion: https://postgr.es/m/9813f079-f16b-61c8-9ab7-4363cab28d80@lab.ntt.co.jp
Discussion: https://postgr.es/m/29069.1555970894@sss.pgh.pa.us
2019-04-30 15:03:50 -04:00
Alvaro Herrera 9f8b717a80 Message style fixes 2019-04-30 10:33:37 -04:00
Alvaro Herrera 9a83afecb7 Widen tuple counter variables from long to int64
Mistake in ab0dfc961b6a; progress reporting would have wrapped around
for indexes created with more than 2^31 tuples.

Reported-by: Peter Geoghegan
Discussion: https://postgr.es/m/CAH2-Wz=WbNxc5ob5NJ9yqo2RMJ0q4HXDS30GVCobeCvC9A1L9A@mail.gmail.com
2019-04-30 10:27:38 -04:00
Andres Freund 3dbb317d32 Fix potential assertion failure when reindexing a pg_class index.
When reindexing individual indexes on pg_class it was possible to
either trigger an assertion failure:
TRAP: FailedAssertion("!(!ReindexIsProcessingIndex(((index)->rd_id)))

That's because reindex_index() called SetReindexProcessing() - which
enables an asserts ensuring no index insertions happen into the index
- before calling RelationSetNewRelfilenode(). That not correct for
indexes on pg_class, because RelationSetNewRelfilenode() updates the
relevant pg_class row, which needs to update the indexes.

The are two reasons this wasn't noticed earlier. Firstly the bug
doesn't trigger when reindexing all of pg_class, as reindex_relation
has code "hiding" all yet-to-be-reindexed indexes. Secondly, the bug
only triggers when the the update to pg_class doesn't turn out to be a
HOT update - otherwise there's no index insertion to trigger the
bug. Most of the time there's enough space, making this bug hard to
trigger.

To fix, move RelationSetNewRelfilenode() to before the
SetReindexProcessing() (and, together with some other code, to outside
of the PG_TRY()).

To make sure the error checking intended by SetReindexProcessing() is
more robust, modify CatalogIndexInsert() to check
ReindexIsProcessingIndex() even when the update is a HOT update.

Also add a few regression tests for REINDEXing of system catalogs.

The last two improvements would have prevented some of the issues
fixed in 5c1560606d from being introduced in the first place.

Reported-By: Michael Paquier
Diagnosed-By: Tom Lane and Andres Freund
Author: Andres Freund
Reviewed-By: Tom Lane
Discussion: https://postgr.es/m/20190418011430.GA19133@paquier.xyz
Backpatch: 9.4-, the bug is present in all branches
2019-04-29 19:42:08 -07:00
Andres Freund 5c1560606d Fix several recently introduced issues around handling new relation forks.
Most of these stem from d25f519107 "tableam: relation creation, VACUUM
FULL/CLUSTER, SET TABLESPACE.".

1) To pass data to the relation_set_new_filenode()
   RelationSetNewRelfilenode() was made to update RelationData.rd_rel
   directly. That's not OK however, as it makes the relcache entries
   temporarily inconsistent. Which among other scenarios is a problem
   if a REINDEX targets an index on pg_class - the
   CatalogTupleUpdate() in RelationSetNewRelfilenode().  Presumably
   that was introduced because other places in the code do so - while
   those aren't "good practice" they don't appear to be actively
   buggy (e.g. because system tables may not be targeted).

   I (Andres) should have caught this while reviewing and signficantly
   evolving the code in that commit, mea culpa.

   Fix that by instead passing in the new RelFileNode as separate
   argument to relation_set_new_filenode() and rely on the relcache to
   update the catalog entry. Also revert that the
   RelationMapUpdateMap() call was changed to immediate, and undo some
   other more unnecessary changes.

2) Document that the relation_set_new_filenode cannot rely on the
   whole relcache entry to be valid. It might be worthwhile to
   refactor the code to never have to rely on that, but given the way
   heap_create() is currently coded, that'd be a large change.

3) ATExecSetTableSpace() shouldn't do FlushRelationBuffers() itself. A
   table AM might not use shared buffers at all. Move to
   index_copy_data() and heapam_relation_copy_data().

4) heapam_relation_set_new_filenode() previously sometimes accessed
   rel->rd_rel->relpersistence rather than the `persistence`
   argument. Code movement mistake.

5) Previously heapam_relation_set_new_filenode() re-opened the smgr
   relation to create the init for, if necesary. Instead have
   RelationCreateStorage() return the SMgrRelation and use it to
   create the init fork.

6) Add a note about the danger of modifying the relcache directly to
   ATExecSetTableSpace() - it's currently not a bug because there's a
   check ERRORing for catalog tables.

Regression tests and assertion improvements that together trigger the
bug described in 1) will be added in a later commit, as there is a
related bug on all branches.

Reported-By: Michael Paquier
Diagnosed-By: Tom Lane and Andres Freund
Author: Andres Freund
Reviewed-By: Tom Lane
Discussion: https://postgr.es/m/20190418011430.GA19133@paquier.xyz
2019-04-29 19:28:05 -07:00
Peter Geoghegan 9ee7414ed0 Remove obsolete _bt_insert_parent() comment.
Remove a comment that refers to a coding practice that was fully removed
by commit a8b8f4db, which introduced MarkBufferDirty().  It looks like
the comment was even obsolete before then, since it concerns
write-ordering dependencies with synchronous buffer writes.
2019-04-29 14:14:38 -07:00
Tom Lane a1a789eb5a In walreceiver, don't try to do ereport() in a signal handler.
This is quite unsafe, even for the case of ereport(FATAL) where we won't
return control to the interrupted code, and despite this code's use of
a flag to restrict the areas where we'd try to do it.  It's possible
for example that we interrupt malloc or free while that's holding a lock
that's meant to protect against cross-thread interference.  Then, any
attempt to do malloc or free within ereport() will result in a deadlock,
preventing the walreceiver process from exiting in response to SIGTERM.
We hypothesize that this explains some hard-to-reproduce failures seen
in the buildfarm.

Hence, get rid of the immediate-exit code in WalRcvShutdownHandler,
as well as the logic associated with WalRcvImmediateInterruptOK.
Instead, we need to take care that potentially-blocking operations
in the walreceiver's data transmission logic (libpqwalreceiver.c)
will respond reasonably promptly to the process's latch becoming
set and then call ProcessWalRcvInterrupts.  Much of the needed code
for that was already present in libpqwalreceiver.c.  I refactored
things a bit so that all the uses of PQgetResult use latch-aware
waiting, but didn't need to do much more.

These changes should be enough to ensure that libpqwalreceiver.c
will respond promptly to SIGTERM whenever it's waiting to receive
data.  In principle, it could block for a long time while waiting
to send data too, and this patch does nothing to guard against that.
I think that that hazard is mostly theoretical though: such blocking
should occur only if we fill the kernel's data transmission buffers,
and we don't generally send enough data to make that happen without
waiting for input.  If we find out that the hazard isn't just
theoretical, we could fix it by using PQsetnonblocking, but that
would require more ticklish changes than I care to make now.

This is a bug fix, but it seems like too big a change to push into
the back branches without much more testing than there's time for
right now.  Perhaps we'll back-patch once we have more confidence
in the change.

Patch by me; thanks to Thomas Munro for review.

Discussion: https://postgr.es/m/20190416070119.GK2673@paquier.xyz
2019-04-29 12:26:07 -04:00
Peter Eisentraut cd3e27464c Fix potential catalog corruption with temporary identity columns
If a temporary table with an identity column and ON COMMIT DROP is
created in a single-statement transaction (not useful, but allowed),
it would leave the catalog corrupted.  We need to add a
CommandCounterIncrement() so that PreCommit_on_commit_actions() sees
the created dependency between table and sequence and can clean it
up.

The analogous and more useful case of doing this in a transaction
block already runs some CommandCounterIncrement() before it gets to
the on-commit cleanup, so it wasn't a problem in practical use.

Several locations for placing the new CommandCounterIncrement() call
were discussed.  This patch places it at the end of
standard_ProcessUtility().  That would also help if other commands
were to create catalog entries that some on-commit action would like
to see.

Bug: #15631
Reported-by: Serge Latyntsev <dnsl48@gmail.com>
Author: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
2019-04-29 08:49:03 +02:00
Noah Misch 90e7f31773 Use preprocessor conditions compatible with Emacs indent.
Emacs wrongly indented hundreds of subsequent lines.
2019-04-28 12:56:53 -07:00
Tom Lane e481d26285 Clean up minor warnings from buildfarm.
Be more consistent about use of XXXGetDatum macros in new jsonpath
code.  This is mostly to avoid having code that looks randomly
different from everyplace else that's doing the exact same thing.

In pg_regress.c, avoid an unreferenced-function warning from
compilers that don't understand pg_attribute_unused().  Putting
the function inside the same #ifdef as its only caller is more
straightforward coding anyway.

In be-secure-openssl.c, avoid use of pg_attribute_unused() on a label.
That's pretty creative, but there's no good reason to suppose that
it's portable, and there's absolutely no need to use goto's here in the
first place.  (This wasn't actually causing any buildfarm complaints,
but it's new code in v12 so it has no portability track record.)
2019-04-28 12:45:55 -04:00
Tom Lane c01eb619a8 Apply stopgap fix for bug #15672.
Fix DefineIndex so that it doesn't attempt to pass down a to-be-reused
index relfilenode to a child index creation, and fix TryReuseIndex
to not think that reuse is sensible for a partitioned index.

In v11, this fixes a problem where ALTER TABLE on a partitioned table
could assign the same relfilenode to several different child indexes,
causing very nasty catalog corruption --- in fact, attempting to DROP
the partitioned table then leads not only to a database crash, but to
inability to restart because the same crash will recur during WAL replay.

Either of these two changes would be enough to prevent the failure, but
since neither action could possibly be sane, let's put in both changes
for future-proofing.

In HEAD, no such bug manifests, but that's just an accidental consequence
of having changed the pg_class representation of partitioned indexes to
have relfilenode = 0.  Both of these changes still seem like smart
future-proofing.

This is only a stop-gap because the code for ALTER TABLE on a partitioned
table with a no-op type change still leaves a great deal to be desired.
As the added regression tests show, it gets things wrong for comments on
child indexes/constraints, and it is regenerating child indexes it doesn't
have to.  However, fixing those problems will take more work which may not
get back-patched into v11.  We need a fix for the corruption problem now.

Per bug #15672 from Jianing Yang.

Patch by me, regression test cases based on work by Amit Langote,
who also did a lot of the investigative work.

Discussion: https://postgr.es/m/15672-b9fa7db32698269f@postgresql.org
2019-04-26 17:18:07 -04:00
Alvaro Herrera 05b38c7e63 Fix partitioned index attachment
When an existing index in a partition is attached to a new index on
its parent, we forgot to set the "relispartition" flag correctly, which
meant that it was not possible to find the index in various operations,
such as adding a foreign key constraint that references that partitioned
table.  One of four places that was assigning the parent index was
forgetting to do that, so fix by shifting responsibility of updating the
flag to the routine that changes the parent.

Author: Amit Langote, Álvaro Herrera
Reported-by: Hubert "depesz" Lubaczewski
Discussion: https://postgr.es/m/CA+HiwqHMsRtRYRWYTWavKJ8x14AFsv7bmAV46mYwnfD3vy8goQ@mail.gmail.com
2019-04-25 11:22:29 -04:00
Fujii Masao 978b032d1f Fix function names in comments.
Commit 3eb77eba5a renamed some functions, but forgot to
update some comments referencing to those functions.
This commit fixes those function names in the comments.

Kyotaro Horiguchi
2019-04-25 23:43:48 +09:00
Alvaro Herrera 87259588d0 Fix tablespace inheritance for partitioned rels
Commit ca4103025d left a few loose ends.  The most important one
(broken pg_dump output) is already fixed by virtue of commit
3b23552ad8, but some things remained:

* When ALTER TABLE rewrites tables, the indexes must remain in the
  tablespace they were originally in.  This didn't work because
  index recreation during ALTER TABLE runs manufactured SQL (yuck),
  which runs afoul of default_tablespace in competition with the parent
  relation tablespace.  To fix, reset default_tablespace to the empty
  string temporarily, and add the TABLESPACE clause as appropriate.

* Setting a partitioned rel's tablespace to the database default is
  confusing; if it worked, it would direct the partitions to that
  tablespace regardless of default_tablespace.  But in reality it does
  not work, and making it work is a larger project.  Therefore, throw
  an error when this condition is detected, to alert the unwary.

Add some docs and tests, too.

Author: Álvaro Herrera
Discussion: https://postgr.es/m/CAKJS1f_1c260nOt_vBJ067AZ3JXptXVRohDVMLEBmudX1YEx-A@mail.gmail.com
2019-04-25 10:31:32 -04:00
Tom Lane 0fae846232 Fix some minor postmaster-state-machine issues.
In sigusr1_handler, don't ignore PMSIGNAL_ADVANCE_STATE_MACHINE based
on pmState.  The restriction is unnecessary (PostmasterStateMachine
should work in any state), not future-proof (since it makes too many
assumptions about why the signal might be sent), and broken even today
because a race condition can make it necessary to respond to the signal
in PM_WAIT_READONLY state.  The race condition seems unlikely, but
if it did happen, a hot-standby postmaster could fail to shut down
after receiving a smart-shutdown request.

In MaybeStartWalReceiver, don't clear the WalReceiverRequested flag
if the fork attempt fails.  Leaving it set allows us to try
again in future iterations of the postmaster idle loop.  (The startup
process would eventually send a fresh request signal, but this change
may allow us to retry the fork sooner.)

Remove an obsolete comment and unnecessary test in
PostmasterStateMachine's handling of PM_SHUTDOWN_2 state.  It's not
possible to have a live walreceiver in that state, and AFAICT has not
been possible since commit 5e85315ea.  This isn't a live bug, but the
false comment is quite confusing to readers.

In passing, rearrange sigusr1_handler's CheckPromoteSignal tests so that
we don't uselessly perform stat() calls that we're going to ignore the
results of.

Add some comments clarifying the behavior of MaybeStartWalReceiver;
I very nearly rearranged it in a way that'd reintroduce the race
condition fixed in e5d494d78.  Mea culpa for not commenting that
properly at the time.

Back-patch to all supported branches.  The PMSIGNAL_ADVANCE_STATE_MACHINE
change is the only one of even minor significance, but we might as well
keep this code in sync across branches.

Discussion: https://postgr.es/m/9001.1556046681@sss.pgh.pa.us
2019-04-24 14:15:44 -04:00
Alvaro Herrera 0a999e1290 Unify error messages
... for translatability purposes.
2019-04-24 09:26:13 -04:00
Andres Freund fdc7efcc30 Allow pg_class xid & multixid horizons to not be set.
This allows table AMs that don't need these horizons. This was already
documented in the tableam relation_set_new_filenode callback, but an
assert prevented if from actually working (the test AM code contained
the change itself). Defang the asserts in the general code, and move
the stronger ones into heap AM.

Relatedly, after CLUSTER/VACUUM, we'd always assign a relfrozenxid /
relminmxid. Change the table_relation_copy_for_cluster() interface to
allow the AM to overwrite the horizons that get set on the pg_class
entry.  This'd also in the future allow AMs like heap to compute a
relfrozenxid during rewrite that's the table's actual minimum rather
than a pre-determined value.  Arguably it'd have been better to move
the whole computation / setting of those values into the callback, but
it seems likely that for other reasons it'd be better to be able to
use one value to vacuum/cluster multiple tables (e.g. a toast's
horizon shouldn't be different than the table's).

Reported-By: Heikki Linnakangas
Author: Andres Freund
Discussion: https://postgr.es/m/9a7fb9cc-2419-5db7-8840-ddc10c93f122@iki.fi
2019-04-23 21:42:12 -07:00
Tom Lane 7ad1cd31bf Repair assorted issues in locale data extraction.
cache_locale_time (extraction of LC_TIME-related info) had never been
taught the lessons we previously learned about extraction of info related
to LC_MONETARY and LC_NUMERIC.  Specifically, commit 95a777c61 taught
PGLC_localeconv() that data coming out of localeconv() was in an encoding
determined by the relevant locale, but we didn't realize that there's a
similar issue with strftime().  And commit a4930e7ca hardened
PGLC_localeconv() against errors occurring partway through, but failed
to do likewise for cache_locale_time().  So, rearrange the latter
function to perform encoding conversion and not risk failure while
it's got the locales set to temporary values.

This time around I also changed PGLC_localeconv() to treat it as FATAL
if it can't restore the previous settings of the locale values.  There
is no reason (except possibly OOM) for that to fail, and proceeding with
the wrong locale values seems like a seriously bad idea --- especially
on Windows where we have to also temporarily change LC_CTYPE.  Also,
protect against the possibility that we can't identify the codeset
reported for LC_MONETARY or LC_NUMERIC; rather than just failing,
try to validate the data without conversion.

The user-visible symptom this fixes is that if LC_TIME is set to a locale
name that implies an encoding different from the database encoding,
non-ASCII localized day and month names would be retrieved in the wrong
encoding, leading to either unexpected encoding-conversion error reports
or wrong output from to_char().  The other possible failure modes are
unlikely enough that we've not seen reports of them, AFAIK.

The encoding conversion problems do not manifest on Windows, since
we'd already created special-case code to handle that issue there.

Per report from Juan José Santamaría Flecha.  Back-patch to all
supported versions.

Juan José Santamaría Flecha and Tom Lane

Discussion: https://postgr.es/m/CAC+AXB22So5aZm2vZe+MChYXec7gWfr-n-SK-iO091R0P_1Tew@mail.gmail.com
2019-04-23 18:51:30 -04:00
Peter Geoghegan 9b10926263 Prevent O(N^2) unique index insertion edge case.
Commit dd299df8 made nbtree treat heap TID as a tiebreaker column,
establishing the principle that there is only one correct location (page
and page offset number) for every index tuple, no matter what.
Insertions of tuples into non-unique indexes proceed as if heap TID
(scan key's scantid) is just another user-attribute value, but
insertions into unique indexes are more delicate.  The TID value in
scantid must initially be omitted to ensure that the unique index
insertion visits every leaf page that duplicates could be on.  The
scantid is set once again after unique checking finishes successfully,
which can force _bt_findinsertloc() to step right one or more times, to
locate the leaf page that the new tuple must be inserted on.

Stepping right within _bt_findinsertloc() was assumed to occur no more
frequently than stepping right within _bt_check_unique(), but there was
one important case where that assumption was incorrect: inserting a
"duplicate" with NULL values.  Since _bt_check_unique() didn't do any
real work in this case, it wasn't appropriate for _bt_findinsertloc() to
behave as if it was finishing off a conventional unique insertion, where
any existing physical duplicate must be dead or recently dead.
_bt_findinsertloc() might have to grovel through a substantial portion
of all of the leaf pages in the index to insert a single tuple, even
when there were no dead tuples.

To fix, treat insertions of tuples with NULLs into a unique index as if
they were insertions into a non-unique index: never unset scantid before
calling _bt_search() to descend the tree, and bypass _bt_check_unique()
entirely.  _bt_check_unique() is no longer responsible for incoming
tuples with NULL values.

Discussion: https://postgr.es/m/CAH2-Wzm08nr+JPx4jMOa9CGqxWYDQ-_D4wtPBiKghXAUiUy-nQ@mail.gmail.com
2019-04-23 10:33:57 -07:00
Tom Lane f4a3fdfbdc Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY.
Up to now, DefineIndex() was responsible for adding attnotnull constraints
to the columns of a primary key, in any case where it hadn't been
convenient for transformIndexConstraint() to mark those columns as
is_not_null.  It (or rather its minion index_check_primary_key) did this
by executing an ALTER TABLE SET NOT NULL command for the target table.

The trouble with this solution is that if we're creating the index due
to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional
sub-commands, the inner ALTER TABLE's operations executed at the wrong
time with respect to the outer ALTER TABLE's operations.  In particular,
the inner ALTER would perform a validation scan at a point where the
table's storage might be inconsistent with its catalog entries.  (This is
on the hairy edge of being a security problem, but AFAICS it isn't one
because the inner scan would only be interested in the tuples' null
bitmaps.)  This can result in unexpected failures, such as the one seen
in bug #15580 from Allison Kaptur.

To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(),
reducing index_check_primary_key's role to verifying that the columns are
already not null.  (It shouldn't ever see such a case, but it seems wise
to keep the check for safety.)  Instead, make transformIndexConstraint()
generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of
the ADD PRIMARY KEY operation in every case where it can't force the
column to be created already-not-null.  This requires only minor surgery
in parse_utilcmd.c, and it makes for a much more satisfying spec for
transformIndexConstraint(): it's no longer having to take it on faith
that someone else will handle addition of NOT NULL constraints.

To make that work, we have to move the execution of AT_SetNotNull into
an ALTER pass that executes ahead of AT_PASS_ADD_INDEX.  I moved it to
AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure
when the column is being added in the same command.  This incidentally
fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for
AT_SetIdentity: it didn't work either for a newly-added column.

Playing around with this exposed a separate bug in ALTER TABLE ONLY ...
ADD PRIMARY KEY for partitioned tables.  The intent of the ONLY modifier
in that context is to prevent doing anything that would require holding
lock for a long time --- but the implied SET NOT NULL would recurse to
the child partitions, and do an expensive validation scan for any child
where the column(s) were not already NOT NULL.  To fix that, invent a
new ALTER subcommand AT_CheckNotNull that just insists that a child
column be already NOT NULL, and apply that, not AT_SetNotNull, when
recursing to children in this scenario.  This results in a slightly laxer
definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables,
too: that command will now work as long as all children are already NOT
NULL, whereas before it just threw up its hands if there were any
partitions.

In passing, clean up the API of generateClonedIndexStmt(): remove a
useless argument, ensure that the output argument is not left undefined,
update the header comment.

A small side effect of this change is that no-such-column errors in ALTER
TABLE ADD PRIMARY KEY now produce a different message that includes the
table name, because they are now detected by the SET NOT NULL step which
has historically worded its error that way.  That seems fine to me, so
I didn't make any effort to avoid the wording change.

The basic bug #15580 is of very long standing, and these other bugs
aren't new in v12 either.  However, this is a pretty significant change
in the way ALTER TABLE ADD PRIMARY KEY works.  On balance it seems best
not to back-patch, at least not till we get some more confidence that
this patch has no new bugs.

Patch by me, but thanks to Jie Zhang for a preliminary version.

Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org
Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 12:25:27 -04:00
Tom Lane c06e3550dc Don't request pretty-printed output from xmlNodeDump().
xml.c passed format = 1 to xmlNodeDump(), resulting in sometimes getting
extra whitespace (newlines + spaces) in the output.  We don't really want
that, first because whitespace might be semantically significant in some
XML uses, and second because it happens only very inconsistently.  Only
one case in our regression tests is affected.

This potentially affects the results of xpath() and the XMLTABLE construct,
when emitting nodeset values.

Note that the older code in contrib/xml2 doesn't do this; it seems
to have been an aboriginal bad decision in commit ea3b212fe.

While this definitely seems like a bug to me, the small number of
complaints to date argues against back-patching a behavioral change.
Hence, fix in HEAD only, at least for now.

Per report from Jean-Marc Voillequin.

Discussion: https://postgr.es/m/1EC8157EB499BF459A516ADCF135ADCE3A23A9CA@LON-WGMSX712.ad.moodys.net
2019-04-23 10:51:07 -04:00
Michael Paquier ccae190b91 Fix detection of passwords hashed with MD5 or SCRAM-SHA-256
This commit fixes a couple of issues related to the way password
verifiers hashed with MD5 or SCRAM-SHA-256 are detected, leading to
being able to store in catalogs passwords which do not follow the
supported hash formats:
- A MD5-hashed entry was checked based on if its header uses "md5" and
if the string length matches what is expected.  Unfortunately the code
never checked if the hash only used hexadecimal characters, as reported
by Tom Lane.
- A SCRAM-hashed entry was checked based on only its header, which
should be "SCRAM-SHA-256$", but it never checked for any fields
afterwards, as reported by Jonathan Katz.

Backpatch down to v10, which is where SCRAM has been introduced, and
where password verifiers in plain format have been removed.

Author: Jonathan Katz
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/016deb6b-1f0a-8e9f-1833-a8675b170aa9@postgresql.org
Backpatch-through: 10
2019-04-23 15:43:21 +09:00
Andres Freund b5f58cf213 Convert gist to compute page level xid horizon on primary.
Due to parallel development, gist added the missing conflict
information in c952eae52a, while 558a9165e0 moved that computation
to the primary for the index types that already had it.  Thus adapt
gist to also compute on the primary, using
index_compute_xid_horizon_for_tuples() instead of its own copy of the
logic.

This also adds pg_waldump support for XLOG_GIST_DELETE records, which
previously was not properly present.

Bumps WAL version.

Author: Andres Freund
Discussion: https://postgr.es/m/20190406050243.bszosdg4buvabfrt@alap3.anarazel.de
2019-04-22 14:28:30 -07:00
Tomas Vondra d08c44f7a4 Fix mvdistinct and dependencies size calculations
The formulas used to calculate size while (de)serializing mvndistinct
and functional dependencies were based on offset() of the structs. But
that is incorrect, because the structures are not copied directly, we
we copy the individual fields directly.

At the moment this works fine, because there is no alignment padding
on any platform we support. But it might break if we ever added some
fields into any of the structs, for example. It's also confusing.

Fixed by reworking the macros to directly sum sizes of serialized
fields. The macros are now useful only for serialiation, so there is
no point in keeping them in the public header file. So make them
private by moving them to the .c files.

Also adds a couple more asserts to check the serialization, and fixes
an incorrect allocation of MVDependency instead of (MVDependency *).

Reported-By: Tom Lane
Discussion: https://postgr.es/m/29785.1555365602@sss.pgh.pa.us
2019-04-21 20:23:34 +02:00
Andres Freund b8b94ea129 Fix slot type issue for fuzzy distance index scan over out-of-core table AM.
For amcanreorderby scans the nodeIndexscan.c's reorder queue holds
heap tuples, but the underlying table likely does not. Before this fix
we'd return different types of slots, depending on whether the tuple
came from the reorder queue, or from the index + table.

While that could be fixed by signalling that the node doesn't return a
fixed type of slot, it seems better to instead remove the separate
slot for the reorder queue, and use ExecForceStoreHeapTuple() to store
tuples from the queue. It's not particularly common to need
reordering, after all.

This reverts most of the iss_ReorderQueueSlot related changes to
nodeIndexscan.c made in 1a0586de36, except that now
ExecForceStoreHeapTuple() is used instead of ExecStoreHeapTuple().

Noticed when testing zheap against the in-core version of tableam.

Author: Andres Freund
2019-04-19 11:42:37 -07:00
Andres Freund 88e6ad3054 Fix two memory leaks around force-storing tuples in slots.
As reported by Tom, when ExecStoreMinimalTuple() had to perform a
conversion to store the minimal tuple in the slot, it forgot to
respect the shouldFree flag, and leaked the tuple into the current
memory context if true.  Fix that by freeing the tuple in that case.

Looking at the relevant code made me (Andres) realize that not having
the shouldFree parameter to ExecForceStoreHeapTuple() was a bad
idea. Some callers had to locally implement the necessary logic, and
in one case it was missing, creating a potential per-group leak in
non-hashed aggregation.

The choice to not free the tuple in ExecComputeStoredGenerated() is
not pretty, but not introduced by this commit - I'll start a separate
discussion about it.

Reported-By: Tom Lane
Discussion: https://postgr.es/m/366.1555382816@sss.pgh.pa.us
2019-04-19 11:39:56 -07:00
Tom Lane 4d5840cea9 Fix problems with auto-held portals.
HoldPinnedPortals() did things in the wrong order: it must not mark
a portal autoHeld until it's been successfully held.  Otherwise,
a failure while persisting the portal results in a server crash
because we think the portal is in a good state when it's not.

Also add a check that portal->status is READY before attempting to
hold a pinned portal.  We have such a check before the only other
use of HoldPortal(), so it seems unwise not to check it here.

Lastly, rethink the responsibility for where to call HoldPinnedPortals.
The comment for it imagined that it was optional for any individual PL
to call it or not, but that cannot be the case: if some outer level of
procedure has a pinned portal, failing to persist it when an inner
procedure commits is going to be trouble.  Let's have SPI do it instead
of the individual PLs.  That's not a complete solution, since in theory
a PL might not be using SPI to perform commit/rollback, but such a PL
is going to have to be aware of lots of related requirements anyway.
(This change doesn't cause an API break for any external PLs that might
be calling HoldPinnedPortals per the old regime, because calling it
twice during a commit or rollback sequence won't hurt.)

Per bug #15703 from Julian Schauder.  Back-patch to v11 where this code
came in.

Discussion: https://postgr.es/m/15703-c12c5bc0ea34ba26@postgresql.org
2019-04-19 11:20:37 -04:00
Michael Paquier 148266fa35 Fix collection of typos and grammar mistakes in docs and comments
Author: Justin Pryzby
Discussion: https://postgr.es/m/20190330224333.GQ5815@telsasoft.com
2019-04-19 16:57:40 +09:00
Andres Freund 75e03eabea Fix potential use-after-free for BEFORE UPDATE row triggers on non-core AMs.
When such a trigger returns the old row version, it naturally get
stored in the slot for the trigger result. When a table AMs doesn't
store HeapTuples internally, ExecBRUpdateTriggers() frees the old row
version passed to triggers - but before this fix it might still be
referenced by the slot holding the new tuple.

Noticed when running the out-of-core zheap AM against the in-core
version of tableam.

Author: Andres Freund
2019-04-18 17:53:54 -07:00
Peter Eisentraut bb385c4fb0 Fix handling of temp and unlogged tables in FOR ALL TABLES publications
If a FOR ALL TABLES publication exists, temporary and unlogged tables
are ignored for publishing changes.  But CheckCmdReplicaIdentity()
would still check in that case that such a table has a replica
identity set before accepting updates.  To fix, have
GetRelationPublicationActions() return that such a table publishes no
actions.

Discussion: https://www.postgresql.org/message-id/f3f151f7-c4dd-1646-b998-f60bd6217dd3@2ndquadrant.com
2019-04-18 08:55:55 +02:00
Bruce Momjian fb9c475597 postgresql.conf.sample: add proper defaults for include actions
Previously, include actions include_dir, include_if_exists, and include
listed commented-out values which were not the defaults, which is
inconsistent with other entries.  Instead, replace them with '', which
is the default value.

Reported-by: Emanuel Araújo

Discussion: https://postgr.es/m/CAMuTAkYMx6Q27wpELDR3_v9aG443y7ZjeXu15_+1nGUjhMWOJA@mail.gmail.com

Backpatch-through: 9.4
2019-04-17 18:12:10 -04:00
Tom Lane 8cde7f4948 Fix assorted minor bogosity in GSSAPI transport error messages.
I noted that some buildfarm members were complaining about %ld being
used to format values that are (probably) declared size_t.  Use %zu
instead, and insert a cast just in case some versions of the GSSAPI
API declare the length field differently.  While at it, clean up
gratuitous differences in wording of equivalent messages, show
the complained-of length in all relevant messages not just some,
include trailing newline where needed, adjust random deviations
from project-standard code layout and message style, etc.
2019-04-17 17:06:50 -04:00
Tom Lane b4f96d69ad Minor jsonpath fixes.
Restore missed "make clean" rule, fix misspelling.

John Naylor

Discussion: https://postgr.es/m/CACPNZCt5B8jDCCGQiFoSuqmg-za_NCy4QDioBTLaNRih9+-bXg@mail.gmail.com
2019-04-17 13:37:00 -04:00
Magnus Hagander 252b707bc4 Return NULL for checksum failures if checksums are not enabled
Returning 0 could falsely indicate that there is no problem. NULL
correctly indicates that there is no information about potential
problems.

Also return 0 as numbackends instead of NULL for shared objects (as no
connection can be made to a shared object only).

Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
2019-04-17 13:51:48 +02:00
Michael Paquier 9010156445 Fix thinko introduced by 82a5649 in slot.c
When saving a replication slot, failing to close the temporary path used
to save the slot information is considered as a failure and reported as
such.  However the code forgot to leave immediately as other failure
paths do.

Noticed while looking up at this area of the code for another patch.
2019-04-17 10:01:22 +09:00
Michael Paquier 47ac2033d4 Simplify some ERROR paths clearing wait events and transient files
Transient files and wait events get normally cleaned up when seeing an
exception (be it in the context of a transaction for a backend or
another process like the checkpointer), hence there is little point in
complicating error code paths to do this work.  This shaves a bit of
code, and removes some extra handling with errno which needed to be
preserved during the cleanup steps done.

Reported-by: Masahiko Sawada
Author: Michael Paquier
Reviewed-by: Tom Lane, Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoDhHYVq5KkXfkaHhmjA-zJYj-e4teiRAJefvXuKJz1tKQ@mail.gmail.com
2019-04-17 09:51:45 +09:00
Michael Paquier a6dcf9df4d Rework handling of invalid indexes with REINDEX CONCURRENTLY
Per discussion with others, allowing REINDEX INDEX CONCURRENTLY to work
for invalid indexes when working directly on them can have a lot of
value to unlock situations with invalid indexes without having to use a
dance involving DROP INDEX followed by an extra CREATE INDEX
CONCURRENTLY (which would not work for indexes with constraint
dependency anyway).  This also does not create extra bloat on the
relation involved as this works on individual indexes, so let's enable
it.

Note that REINDEX TABLE CONCURRENTLY still bypasses invalid indexes as
we don't want to bloat the number of indexes defined on a relation in
the event of multiple and successive failures of REINDEX CONCURRENTLY.

More regression tests are added to cover those behaviors, using an
invalid index created with CREATE INDEX CONCURRENTLY.

Reported-by: Dagfinn Ilmari Mannsåker, Álvaro Herrera
Author: Michael Paquier
Reviewed-by: Peter Eisentraut, Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/20190411134947.GA22043@alvherre.pgsql
2019-04-17 09:33:51 +09:00
Michael Paquier 5ed4b123b6 Remove duplicate assignment when initializing logical decoder context
The private data in the WAL reader is already getting set when
allocating it.

Author: Antonin Houska
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/30563.1555329094@localhost
2019-04-16 15:08:38 +09:00
Tomas Vondra 3824ca30d1 Fix pg_mcv_list deserialization
The memcpy() was copying type OIDs in the wrong direction, so the
deserialized MCV list always had them as 0. This is mostly harmless
except when printing the data in pg_mcv_list_items(), in which case
it reported

    ERROR:  cache lookup failed for type 0

Also added a simple regression test for pg_mcv_list_items() function,
printing a single-item MCV list.

Reported-By: Dean Rasheed
Discussion: https://postgr.es/m/CAEZATCX6T0iDTTZrqyec4Cd6b4yuL7euu4=rQRXaVBAVrUi1Cg@mail.gmail.com
2019-04-16 00:01:39 +02:00
Tom Lane 4b40e44f07 Fix failure with textual partition hash keys.
Commit 5e1963fb7 overlooked two places in partbounds.c that now
need to pass a collation identifier to the hash functions for
a partition key column.

Amit Langote, per report from Jesper Pedersen

Discussion: https://postgr.es/m/a620f85a-42ab-e0f3-3337-b04b97e2e2f5@redhat.com
2019-04-15 16:47:09 -04:00
Alexander Korotkov 1e87198182 Fix division by zero in _bt_vacuum_needs_cleanup()
Checks inside _bt_vacuum_needs_cleanup() allow division by zero to happen when
metad->btm_last_cleanup_num_heap_tuples == 0.  This commit adjusts the
expression so that no division by zero might happen.

Reported-by: Piotr Stefaniak
Discussion: https://postgr.es/m/DB8PR03MB5931C41F7787A95313F08322F22A0%40DB8PR03MB5931.eurprd03.prod.outlook.com
Reviewed-by: Masahiko Sawada
Backpatch-through: 11
2019-04-15 20:20:43 +03:00
Etsuro Fujita 3a45321a49 Fix thinko in ExecCleanupTupleRouting().
Commit 3f2393edef changed ExecCleanupTupleRouting() so that it skipped
cleaning up subplan resultrels before calling EndForeignInsert(), but
that would cause an issue: when those resultrels were foreign tables,
the FDWs would fail to shut down.  Repair by skipping it after calling
EndForeignInsert() as before.

Author: Etsuro Fujita
Reviewed-by: David Rowley and Amit Langote
Discussion: https://postgr.es/m/5CAF3B8F.2090905@lab.ntt.co.jp
2019-04-15 19:01:09 +09:00
Peter Eisentraut abb9c63b2c Unbreak index optimization for LIKE on bytea
The same code is used to handle both text and bytea, but bytea is not
collation-aware, so we shouldn't call get_collation_isdeterministic()
in that case, since that will error out with an invalid collation.

Reported-by: Jeevan Chalke <jeevan.chalke@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAM2%2B6%3DWaf3qJ1%3DyVTUH8_yG-SC0xcBMY%2BSFLhvKKNnWNXSUDBw%40mail.gmail.com
2019-04-15 09:29:17 +02:00
Michael Paquier c34677fdaa Fix SHOW ALL command for non-superusers with replication connection
Since Postgres 10, SHOW commands can be triggered with replication
connections in a WAL sender context, however it missed that a
transaction context is needed for syscache lookups.  This commit makes
sure that the syscache lookups can happen correctly by setting a
transaction context when running SHOW commands in a WAL sender.

Superuser-only parameters can be displayed using SHOW commands not only
to superusers, but also to members of system role pg_read_all_settings,
which requires a syscache lookup to check if the connected role is a
member of this system role or not, or the instance crashes.  Superusers
do not need to check the syscache so it worked correctly in this case.

New tests are added to cover this issue.

Reported-by: Alexander Kukushkin
Author: Michael Paquier
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/15734-2daa8761eeed8e20@postgresql.org
Backpatch-through: 10
2019-04-15 12:34:32 +09:00
Tom Lane 5f1433ac5e Prevent memory leaks associated with relcache rd_partcheck structures.
The original coding of generate_partition_qual() just copied the list
of predicate expressions into the global CacheMemoryContext, making it
effectively impossible to clean up when the owning relcache entry is
destroyed --- the relevant code in RelationDestroyRelation() only managed
to free the topmost List header :-(.  This resulted in a session-lifespan
memory leak whenever a table partition's relcache entry is rebuilt.
Fortunately, that's not normally a large data structure, and rebuilds
shouldn't occur all that often in production situations; but this is
still a bug worth fixing back to v10 where the code was introduced.

To fix, put the cached expression tree into its own small memory context,
as we do with other complicated substructures of relcache entries.
Also, deal more honestly with the case that a partition has an empty
partcheck list; while that probably isn't a case that's very interesting
for production use, it's legal.

In passing, clarify comments about how partitioning-related relcache
data structures are managed, and add some Asserts that we're not leaking
old copies when we overwrite these data fields.

Amit Langote and Tom Lane

Discussion: https://postgr.es/m/7961.1552498252@sss.pgh.pa.us
2019-04-13 13:22:26 -04:00
Noah Misch c098509927 Consistently test for in-use shared memory.
postmaster startup scrutinizes any shared memory segment recorded in
postmaster.pid, exiting if that segment matches the current data
directory and has an attached process.  When the postmaster.pid file was
missing, a starting postmaster used weaker checks.  Change to use the
same checks in both scenarios.  This increases the chance of a startup
failure, in lieu of data corruption, if the DBA does "kill -9 `head -n1
postmaster.pid` && rm postmaster.pid && pg_ctl -w start".  A postmaster
will no longer stop if shmat() of an old segment fails with EACCES.  A
postmaster will no longer recycle segments pertaining to other data
directories.  That's good for production, but it's bad for integration
tests that crash a postmaster and immediately delete its data directory.
Such a test now leaks a segment indefinitely.  No "make check-world"
test does that.  win32_shmem.c already avoided all these problems.  In
9.6 and later, enhance PostgresNode to facilitate testing.  Back-patch
to 9.4 (all supported versions).

Reviewed (in earlier versions) by Daniel Gustafsson and Kyotaro HORIGUCHI.

Discussion: https://postgr.es/m/20190408064141.GA2016666@rfd.leadboat.com
2019-04-12 22:36:38 -07:00
Magnus Hagander 77bd49adba Show shared object statistics in pg_stat_database
This adds a row to the pg_stat_database view with datoid 0 and datname
NULL for those objects that are not in a database. This was added
particularly for checksums, but we were already tracking more satistics
for these objects, just not returning it.

Also add a checksum_last_failure column that holds the timestamptz of
the last checksum failure that occurred in a database (or in a
non-dataabase file), if any.

Author: Julien Rouhaud <rjuju123@gmail.com>
2019-04-12 14:04:50 +02:00
Peter Eisentraut ef6f30fe77 Fix REINDEX CONCURRENTLY of partitions
In case of a partition index, when swapping the old and new index, we
also need to attach the new index as a partition and detach the old
one.  Also, to handle partition indexes, we not only need to change
dependencies referencing the index, but also dependencies of the index
referencing something else.  The previous code did this only
specifically for a constraint, but we also need to do this for
partitioned indexes.  So instead write a generic function that does it
for all dependencies.

Author: Michael Paquier <michael@paquier.xyz>
Author: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/DF4PR8401MB11964EDB77C860078C343BEBEE5A0%40DF4PR8401MB1196.NAMPRD84.PROD.OUTLOOK.COM#154df1fedb735190a773481765f7b874
2019-04-12 08:36:05 +02:00
Thomas Munro f7feb020c3 Fix GetNewTransactionId()'s interaction with xidVacLimit.
Commit ad308058 switched to returning a FullTransactionId, but
failed to load the potentially updated value in the case where
xidVacLimit is reached and we release and reacquire the lock.
Repair, closing bug #15727.

While reviewing that commit, also fix the size computation used
by EstimateTransactionStateSize() and switch to the mul_size()
macro traditionally used in such expressions.

Author: Thomas Munro
Reported-by: Roman Zharkov
Discussion: https://postgr.es/m/15727-0be246e7d852d229%40postgresql.org
2019-04-12 16:47:50 +12:00
Michael Paquier d87ab88686 Fix typos in reloptions.c
Author: Kirk Jamison
Discussion: https://postgr.es/m/D09B13F772D2274BB348A310EE3027C6493463@g01jpexmbkw24
2019-04-12 12:56:38 +09:00