Commit Graph

48462 Commits

Author SHA1 Message Date
Andrew Gierth 1fd687a035 Optimizations for integer to decimal output.
Using a lookup table of digit pairs reduces the number of divisions
needed, and calculating the length upfront saves some work; these
ideas are taken from the code previously committed for floats.

David Fetter, reviewed by Kyotaro Horiguchi, Tels, and me.

Discussion: https://postgr.es/m/20190924052620.GP31596%40fetter.org
2020-02-01 21:57:14 +00:00
Michael Paquier 7bae0ad9fc Prevent running pg_basebackup as root
Similarly to pg_upgrade, pg_ctl and initdb, a root user is able to use
--version and --help, but cannot execute the actual operation to avoid
the creation of files with permissions incompatible with the
postmaster.

This is a behavior change, so not back-patching is done.

Author: Ian Barwick
Discussion: https://postgr.es/m/CABvVfJVqOdD2neLkYdygdOHvbWz_5K_iWiqY+psMfA=FeAa3qQ@mail.gmail.com
2020-02-01 18:30:25 +09:00
Thomas Munro 93745f1e01 Fix memory leak on DSM slot exhaustion.
If we attempt to create a DSM segment when no slots are available,
we should return the memory to the operating system.  Previously
we did that if the DSM_CREATE_NULL_IF_MAXSEGMENTS flag was
passed in, but we didn't do it if an error was raised.  Repair.

Back-patch to 9.4, where DSM segments arrived.

Author: Thomas Munro
Reviewed-by: Robert Haas
Reported-by: Julian Backes
Discussion: https://postgr.es/m/CA%2BhUKGKAAoEw-R4om0d2YM4eqT1eGEi6%3DQot-3ceDR-SLiWVDw%40mail.gmail.com
2020-02-01 14:29:13 +13:00
Tom Lane 870ad6a59b Fix not-quite-right string comparison in parse_jsonb_index_flags().
This code would accept "strinX", where X is any 1-byte character,
as meaning "string".  Clearly it wasn't meant to do that.

No back-patch, since this doesn't affect correct queries and
there's some tiny chance we'd break somebody's incorrect query
in a minor release.

Report and patch by Dominik Czarnota.

Discussion: https://postgr.es/m/CABEVAa1dU0mDCAfaT8WF2adVXTDsLVJy_izotg6ze_hh-cn8qQ@mail.gmail.com
2020-01-31 17:26:40 -05:00
Tom Lane 74b35eb468 Fix CheckAttributeType's handling of collations for ranges.
Commit fc7695891 changed CheckAttributeType to recurse into ranges,
but made it pass down the wrong collation (always InvalidOid, since
ranges as such have no collation).  This would result in guaranteed
failure when considering a range type whose subtype is collatable.

Embarrassingly, we lack any regression tests that would expose such
a problem (but fortunately, somebody noticed before we shipped this
bug in any release).

Fix it to pass down the range's subtype collation property instead,
and add some regression test cases to exercise collatable-subtype
ranges a bit more.  Back-patch to all supported branches, as the
previous patch was.

Report and patch by Julien Rouhaud, test cases tweaked by me

Discussion: https://postgr.es/m/CAOBaU_aBWqNweiGUFX0guzBKkcfJ8mnnyyGC_KBQmO12Mj5f_A@mail.gmail.com
2020-01-31 17:03:55 -05:00
Tom Lane 2425f8f714 Fix parallel pg_dump/pg_restore for failure to create worker processes.
If we failed to fork a worker process, or create a communication pipe
for one, WaitForTerminatingWorkers would suffer an assertion failure
if assert-enabled, otherwise crash or go into an infinite loop.  This
was a consequence of not accounting for the startup condition where
we've not yet forked all the workers.

The original bug was that ParallelBackupStart would set workerStatus to
WRKR_IDLE before it had successfully forked a worker.  I made things
worse in commit b7b8cc0cf by not understanding the undocumented fact
that the WRKR_TERMINATED state was also meant to represent the case
where a worker hadn't been started yet: I changed enum T_WorkerStatus
so that *all* the worker slots were initially in WRKR_IDLE state.  But
this wasn't any more broken in practice, since even one slot in the
wrong state would keep WaitForTerminatingWorkers from terminating.

In v10 and later, introduce an explicit T_WorkerStatus value for
worker-not-started, in hopes of preventing future oversights of the
same ilk.  Before that, just document that WRKR_TERMINATED is supposed
to cover that case (partly because it wasn't actively broken, and
partly because the enum is exposed outside parallel.c in those branches,
so there's microscopically more risk involved in changing it).
In all branches, introduce a WORKER_IS_RUNNING status test macro
to hide which T_WorkerStatus values mean that, and be more careful
not to access ParallelSlot fields till we're sure they're valid.

Per report from Vignesh C, though this is my patch not his.
Back-patch to all supported branches.

Discussion: https://postgr.es/m/CALDaNm1Luv-E3sarR+-unz-BjchquHHyfP+YC+2FS2pt_J+wxg@mail.gmail.com
2020-01-31 14:41:49 -05:00
Peter Eisentraut a9cff89f7e Allow building without default socket directory
We have code paths for Unix socket support and no Unix socket support.
Now add a third variant: Unix socket support but do not use a Unix
socket by default in the client or the server, only if you explicitly
specify one.  This will be useful when we enable Unix socket support
on Windows.

To implement this, tweak things so that setting DEFAULT_PGSOCKET_DIR
to "" has the desired effect.  This mostly already worked like that;
only a few places needed to be adjusted.  Notably, the reference to
DEFAULT_PGSOCKET_DIR in UNIXSOCK_PATH() could be removed because all
callers already resolve an empty socket directory setting with a
default if appropriate.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/75f72249-8ae6-322a-63df-4fe03eeccb9f@2ndquadrant.com
2020-01-31 16:28:43 +01:00
Peter Eisentraut 7c23bfd25c Sprinkle some const decorations
This might help clarify the API a bit.
2020-01-31 12:52:08 +01:00
Michael Paquier 7ca8c9706a Fix typo in recently-added TAP test for replication slots
Oversight in commit b0afdca.
2020-01-31 13:57:56 +09:00
Thomas Munro ef02fb15a3 Report time spent in posix_fallocate() as a wait event.
When allocating DSM segments with posix_fallocate() on Linux (see commit
899bd785), report this activity as a wait event exactly as we would if
we were using file-backed DSM rather than shm_open()-backed DSM.

Author: Thomas Munro
Discussion: https://postgr.es/m/CA%2BhUKGKCSh4GARZrJrQZwqs5SYp0xDMRr9Bvb%2BHQzJKvRgL6ZA%40mail.gmail.com
2020-01-31 17:29:41 +13:00
Thomas Munro d061ea21fc Adjust DSM and DSA slot usage constants.
When running a lot of large parallel queries concurrently, or a plan with
a lot of separate Gather nodes, it is possible to run out of DSM slots.
There are better solutions to these problems requiring architectural
redesign work, but for now, let's adjust the constants so that it's more
difficult to hit the limit.

1.  Previously, a DSA area would create up to four segments at each size
before doubling the size.  After this commit, it will create only two at
each size, so it ramps up faster and therefore needs fewer slots.

2.  Previously, the total limit on DSM slots allowed for 2 per connection.
Switch to 5 per connection.

Also remove an obsolete nearby comment.

Author: Thomas Munro
Reviewed-by: Robert Haas, Andres Freund
Discussion: https://postre.es/m/CA%2BhUKGL6H2BpGbiF7Lj6QiTjTGyTLW_vLR%3DSn2tEBeTcYXiMKw%40mail.gmail.com
2020-01-31 17:29:38 +13:00
Tom Lane a069218163 In jsonb_plpython.c, suppress warning message from gcc 10.
Very recent gcc complains that PLyObject_ToJsonbValue could return
a pointer to a local variable.  I think it's wrong; but the coding
is fragile enough, and the savings of one palloc() minimal enough,
that it seems better to just do a palloc() all the time.  (My other
idea of tweaking the if-condition doesn't suppress the warning.)

Back-patch to v11 where this code was introduced.

Discussion: https://postgr.es/m/21547.1580170366@sss.pgh.pa.us
2020-01-30 18:26:12 -05:00
Thomas Munro 74618e77b4 Handle lack of DSM slots in parallel btree build.
If no DSM slots are available, a ParallelContext can still be
created, but its seg pointer is NULL.  Teach parallel btree build
to cope with that by falling back to a regular non-parallel build,
to avoid crashing with a segmentation fault.

Back-patch to 11, where parallel CREATE INDEX landed.

Reported-by: Nicola Contu
Reviewed-by: Peter Geoghegan
Discussion: https://postgr.es/m/CA%2BhUKGJgJEBnkuODBVomyK3MWFvDBbMVj%3Dgdt6DnRPU-5sQ6UQ%40mail.gmail.com
2020-01-31 10:25:34 +13:00
Alvaro Herrera c9d2977519 Clean up newlines following left parentheses
We used to strategically place newlines after some function call left
parentheses to make pgindent move the argument list a few chars to the
left, so that the whole line would fit under 80 chars.  However,
pgindent no longer does that, so the newlines just made the code
vertically longer for no reason.  Remove those newlines, and reflow some
of those lines for some extra naturality.

Reviewed-by: Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/20200129200401.GA6303@alvherre.pgsql
2020-01-30 13:42:14 -03:00
Alvaro Herrera 4e89c79a52 Remove excess parens in ereport() calls
Cosmetic cleanup, not worth backpatching.

Discussion: https://postgr.es/m/20200129200401.GA6303@alvherre.pgsql
Reviewed-by: Tom Lane, Michael Paquier
2020-01-30 13:32:04 -03:00
Tom Lane 2520cf8c2a Fix test failure with non-MULTIPLICITY Perl interpreters.
Per buildfarm.
2020-01-30 10:51:40 -05:00
Fujii Masao e6f1e560e4 Make inherited TRUNCATE perform access permission checks on parent table only.
Previously, TRUNCATE command through a parent table checked the
permissions on not only the parent table but also the children tables
inherited from it. This was a bug and inherited queries should perform
access permission checks on the parent table only. This commit fixes
that bug.

Back-patch to all supported branches.

Author: Amit Langote
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CAHGQGwFHdSvifhJE+-GSNqUHSfbiKxaeQQ7HGcYz6SC2n_oDcg@mail.gmail.com
2020-01-31 00:42:06 +09:00
Michael Paquier b0afdcad21 Fix slot data persistency when advancing physical replication slots
Advancing a physical replication slot with pg_replication_slot_advance()
did not mark the slot as dirty if any advancing was done, preventing the
follow-up checkpoint to flush the slot data to disk.  This caused the
advancing to be lost even on clean restarts.  This does not happen for
logical slots as any advancing marked the slot as dirty.  Per
discussion, the original feature has been implemented so as in the event
of a crash the slot may move backwards to a past LSN.  This property is
kept and more documentation is added about that.

This commit adds some new TAP tests to check the persistency of physical
and logical slots after advancing across clean restarts.

Author: Alexey Kondratov, Michael Paquier
Reviewed-by: Andres Freund, Kyotaro Horiguchi, Craig Ringer
Discussion: https://postgr.es/m/059cc53a-8b14-653a-a24d-5f867503b0ee@postgrespro.ru
Backpatch-through: 11
2020-01-30 11:14:02 +09:00
Tom Lane 26a81bb815 Fix vcregress.pl for new plperl test case.
As of commit 50fc694e4, the plperl tests don't want preinstalled
plperl languages; they now install those themselves.  I'd removed the
--load-extension options from the GNUmakefile, but missed teaching
the MSVC build script about that.

Per buildfarm.
2020-01-29 19:13:34 -05:00
Tom Lane 50fc694e43 Invent "trusted" extensions, and remove the pg_pltemplate catalog.
This patch creates a new extension property, "trusted".  An extension
that's marked that way in its control file can be installed by a
non-superuser who has the CREATE privilege on the current database,
even if the extension contains objects that normally would have to be
created by a superuser.  The objects within the extension will (by
default) be owned by the bootstrap superuser, but the extension itself
will be owned by the calling user.  This allows replicating the old
behavior around trusted procedural languages, without all the
special-case logic in CREATE LANGUAGE.  We have, however, chosen to
loosen the rules slightly: formerly, only a database owner could take
advantage of the special case that allowed installation of a trusted
language, but now anyone who has CREATE privilege can do so.

Having done that, we can delete the pg_pltemplate catalog, moving the
knowledge it contained into the extension script files for the various
PLs.  This ends up being no change at all for the in-core PLs, but it is
a large step forward for external PLs: they can now have the same ease
of installation as core PLs do.  The old "trusted PL" behavior was only
available to PLs that had entries in pg_pltemplate, but now any
extension can be marked trusted if appropriate.

This also removes one of the stumbling blocks for our Python 2 -> 3
migration, since the association of "plpythonu" with Python 2 is no
longer hard-wired into pg_pltemplate's initial contents.  Exactly where
we go from here on that front remains to be settled, but one problem
is fixed.

Patch by me, reviewed by Peter Eisentraut, Stephen Frost, and others.

Discussion: https://postgr.es/m/5889.1566415762@sss.pgh.pa.us
2020-01-29 18:42:43 -05:00
Tom Lane 166ab9c8d3 Teach plpgsql's "make clean" to remove generated test files.
Copy the rules that src/test/regress/GNUmakefile uses for this purpose.
Since these files are .gitignore'd, the mistake wasn't obvious unless
you happened to look at "git status --ignored" in an allegedly clean
tree.

Oversight in commit 1858b105b.  No need for back-patch since that's
not in the back branches.
2020-01-29 11:07:04 -05:00
Robert Haas 006b9dcad4 Add jsonapi.c to Mkvcbuild.pm's @pgcommonallfiles.
My recent commit beb4699091 caused
some buildfarm breakage, as reported by Tom Lane. Try to repair.

This fix is extracted from a larger patch by Andrew Dunstan.

Discussion: http://postgr.es/m/8440ddc9-8347-ca64-1405-845d10e054cd@2ndQuadrant.com
Discussion: http://postgr.es/m/14178.1580312751@sss.pgh.pa.us
2020-01-29 10:50:17 -05:00
Robert Haas beb4699091 Move jsonapi.c and jsonapi.h to src/common.
To make this work, (1) makeJsonLexContextCstringLen now takes the
encoding to be used as an argument; (2) check_stack_depth() is made to
do nothing in frontend code, and (3) elog(ERROR, ...) is changed to
pg_log_fatal + exit in frontend code.

Mark Dilger, reviewed and slightly revised by me.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com
2020-01-29 10:22:51 -05:00
Peter Eisentraut dc788668bb Fail if recovery target is not reached
Before, if a recovery target is configured, but the archive ended
before the target was reached, recovery would end and the server would
promote without further notice.  That was deemed to be pretty wrong.
With this change, if the recovery target is not reached, it is a fatal
error.

Based-on-patch-by: Leif Gunnar Erlandsen <leif@lako.no>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/993736dd3f1713ec1f63fc3b653839f5@lako.no
2020-01-29 15:58:14 +01:00
Michael Paquier 29e321cdd6 Fix dispsize for libpq connection parameters channel_binding and gssencmode
channel_binding's longest allowed value is not "7", it is actually "8".
gssencmode also got that wrong.

A similar mistake has been fixed as of f4051e3.

Backpatch down to v12, where gssencmode has been introduced.

Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20200128053633.GD1552@paquier.xyz
Backpatch-through: 12
2020-01-29 15:08:19 +09:00
Amit Kapila 47bc9ced0d Add --parallel option to vacuumdb command.
Commit 40d964ec99 allowed vacuum command to leverage multiple CPUs by
invoking parallel workers to process indexes.  This commit provides a
'--parallel' option to specify the parallel degree used by vacuum command.

Author: Masahiko Sawada, with few modifications by me
Reviewed-by: Mahendra Singh and Amit Kapila
Discussion: https://postgr.es/m/CAD21AoDTPMgzSkV4E3SFo1CH_x50bf5PqZFQf4jmqjk-C03BWg@mail.gmail.com
2020-01-29 11:08:50 +05:30
Tom Lane 01d9676a53 Fix dangling pointer in EvalPlanQual machinery.
EvalPlanQualStart() supposed that it could re-use the relsubs_rowmark
and relsubs_done arrays from a prior instantiation.  But since they are
allocated in the es_query_cxt of the recheckestate, that's just wrong;
EvalPlanQualEnd() will blow away that storage.  Therefore we were using
storage that could have been reallocated to something else, causing all
sorts of havoc.

I think this was modeled on the old code's handling of es_epqTupleSlot,
but since the code was anyway clearing the arrays at re-use, there's
clearly no expectation of importing any outside state.  So it's just
a dubious savings of a couple of pallocs, which is negligible compared
to setting up a new planstate tree.  Therefore, just allocate the
arrays always.  (I moved the allocations slightly for readability.)

In principle this bug could cause a problem whenever EPQ rechecks are
needed in more than one target table of a ModifyTable plan node.
In practice it seems not quite so easy to trigger as that; I couldn't
readily duplicate a crash with a partitioned target table, for instance.
That's probably down to incidental choices about when to free or
reallocate stuff.  The added isolation test case does seem to reliably
show an assertion failure, though.

Per report from Oleksii Kliukin.  Back-patch to v12 where the bug was
introduced (evidently by commit 3fb307bc4).

Discussion: https://postgr.es/m/EEF05F66-2871-4786-992B-5F45C92FEE2E@hintbits.com
2020-01-28 17:26:37 -05:00
Heikki Linnakangas 30012a04a6 Fix randAccess setting in ReadRecord()
Commit 38a957316d got this backwards.

Author: Kyotaro Horiguchi
Discussion: https://www.postgresql.org/message-id/20200128.194408.2260703306774646445.horikyota.ntt@gmail.com
2020-01-28 12:55:30 +02:00
Thomas Munro 11da6bccd1 Fix compile error on HP C.
Per build farm animal anole, after commit 6f38d4dac3.
2020-01-28 20:30:40 +13:00
Thomas Munro 78aaa0e823 Don't reset latch in ConditionVariablePrepareToSleep().
It's not OK to do that without calling CHECK_FOR_INTERRUPTS().
Let the next wait loop deal with it, following the usual pattern.

One consequence of this bug was that a SIGTERM delivered in a very
narrow timing window could leave a parallel worker process waiting
forever for a condition variable that will never be signaled, after
an error was raised in other process.

The code is a bit different in the stable branches due to commit
1321509f, making problems less likely there.  No back-patch for now,
but we may finish up deciding to make a similar change after more
discussion.

Author: Thomas Munro
Reviewed-by: Shawn Debnath
Reported-by: Tomas Vondra
Discussion: https://postgr.es/m/CA%2BhUKGJOm8zZHjVA8svoNT3tHY0XdqmaC_kHitmgXDQM49m1dA%40mail.gmail.com
2020-01-28 15:28:36 +13:00
Amit Kapila 05f18c6b6b Added relation name in error messages for constraint checks.
This gives more information to the user about the error and it makes such
messages consistent with the other similar messages in the code.

Reported-by: Simon Riggs
Author: Mahendra Singh and Simon Riggs
Reviewed-by: Beena Emerson and Amit Kapila
Discussion: https://postgr.es/m/CANP8+j+7YUvQvGxTrCiw77R23enMJ7DFmyA3buR+fa2pKs4XhA@mail.gmail.com
2020-01-28 07:48:10 +05:30
Michael Paquier ff8ca5fadd Add connection parameters to control SSL protocol min/max in libpq
These two new parameters, named sslminprotocolversion and
sslmaxprotocolversion, allow to respectively control the minimum and the
maximum version of the SSL protocol used for the SSL connection attempt.
The default setting is to allow any version for both the minimum and the
maximum bounds, causing libpq to rely on the bounds set by the backend
when negotiating the protocol to use for an SSL connection.  The bounds
are checked when the values are set at the earliest stage possible as
this makes the checks independent of any SSL implementation.

Author: Daniel Gustafsson
Reviewed-by: Michael Paquier, Cary Huang
Discussion: https://postgr.es/m/4F246AE3-A7AE-471E-BD3D-C799D3748E03@yesql.se
2020-01-28 10:40:48 +09:00
Thomas Munro 6f38d4dac3 Remove dependency on HeapTuple from predicate locking functions.
The following changes make the predicate locking functions more
generic and suitable for use by future access methods:

- PredicateLockTuple() is renamed to PredicateLockTID().  It takes
  ItemPointer and inserting transaction ID instead of HeapTuple.

- CheckForSerializableConflictIn() takes blocknum instead of buffer.

- CheckForSerializableConflictOut() no longer takes HeapTuple or buffer.

Author: Ashwin Agrawal
Reviewed-by: Andres Freund, Kuntal Ghosh, Thomas Munro
Discussion: https://postgr.es/m/CALfoeiv0k3hkEb3Oqk%3DziWqtyk2Jys1UOK5hwRBNeANT_yX%2Bng%40mail.gmail.com
2020-01-28 13:13:04 +13:00
Tom Lane 4589c6a2a3 Apply project best practices to switches over enum values.
In the wake of 1f3a02173, assorted buildfarm members were warning about
"control reaches end of non-void function" or the like.  Do what we've
done elsewhere: in place of a "default" switch case that will prevent
the compiler from warning about unhandled enum values, put a catchall
elog() after the switch.  And return a dummy value to satisfy compilers
that don't know elog() doesn't return.
2020-01-27 18:46:30 -05:00
Robert Haas 73ce2a03f3 Move some code from jsonapi.c to jsonfuncs.c.
Specifically, move those functions that depend on ereport()
from jsonapi.c to jsonfuncs.c, in preparation for allowing
jsonapi.c to be used from frontend code.

A few cases where elog(ERROR, ...) is used for can't-happen
conditions are left alone; we can handle those in some other
way in frontend code.

Reviewed by Mark Dilger and Andrew Dunstan.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com
2020-01-27 11:22:13 -05:00
Robert Haas 1f3a021730 Adjust pg_parse_json() so that it does not directly ereport().
Instead, it now returns a value indicating either success or the
type of error which occurred. The old behavior is still available
by calling pg_parse_json_or_ereport(). If the new interface is
used, an error can be thrown by passing the return value of
pg_parse_json() to json_ereport_error().

pg_parse_json() can still elog() in can't-happen cases, but it
seems like that issue is best handled separately.

Adjust json_lex() and json_count_array_elements() to return an
error code, too.

This is all in preparation for making the backend's json parser
available to frontend code.

Reviewed and/or tested by Mark Dilger and Andrew Dunstan.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com
2020-01-27 11:04:51 -05:00
Thomas Munro 3e4818e9dd Avoid unnecessary shm writes in Parallel Hash Join.
Currently, Parallel Hash Join cannot be used for full/right joins,
so there is no point in setting the match flag.  It turns out that
the cache coherence traffic generated by those writes slows down
large systems running many-core joins, so let's stop doing that.
In future, if we need to use match bits in parallel joins, we might
want to consider setting them only if not already set.

Back-patch to 11, where Parallel Hash Join arrived.

Reported-by: Deng, Gang
Discussion: https://postgr.es/m/0F44E799048C4849BAE4B91012DB910462E9897A%40SHSMSX103.ccr.corp.intel.com
2020-01-27 15:07:03 +13:00
Michael Paquier 10a525230f Fix some memory leaks and improve restricted token handling on Windows
The leaks have been detected by a Coverity run on Windows.  No backpatch
is done as the leaks are minor.

While on it, make restricted token creation more consistent in its error
handling by logging an error instead of a warning if missing
advapi32.dll, which was missing in the NT4 days.  Any modern platform
should have this DLL around.  Now, if the library is not there, an error
is still reported back to the caller, and nothing is done do there is no
behavior change done in this commit.

Author: Ranier Vilela
Discussion: https://postgr.es/m/CAEudQApa9MG0foPkgPX87fipk=vhnF2Xfg+CfUyR08h4R7Mywg@mail.gmail.com
2020-01-27 11:02:05 +09:00
Tom Lane 3ec20c7091 Fix EXPLAIN (SETTINGS) to follow policy about when to print empty fields.
In non-TEXT output formats, the "Settings" field should appear when
requested, even if it would be empty.

Also, get rid of the premature optimization of counting all the
GUC_EXPLAIN variables at startup.  Since there was no provision for
adjusting that count later, all it'd take would be some extension marking
a parameter as GUC_EXPLAIN to risk an assertion failure or memory stomp.
We could make get_explain_guc_options() count those variables on-the-fly,
or dynamically resize its array ... but TBH I do not think that making a
transient array of pointers a bit smaller is worth any extra complication,
especially when you consider all the other transient space EXPLAIN eats.
So just allocate that array at the max possible size.

In HEAD, also add some regression test coverage for this feature.

Because of the memory-stomp hazard, back-patch to v12 where this
feature was added.

Discussion: https://postgr.es/m/19416.1580069629@sss.pgh.pa.us
2020-01-26 16:32:19 -05:00
Thomas Munro f37ff03478 Refactor confusing code in _mdfd_openseg().
As reported independently by a couple of people, _mdfd_openseg() is coded in a
way that seems to imply that the segments could be opened in an order that
isn't strictly sequential.  Even if that were true, it's also using the wrong
comparison.  It's not an active bug, since the condition is always true anyway,
but it's confusing, so replace it with an assertion.

Author: Thomas Munro
Reviewed-by: Andres Freund, Kyotaro Horiguchi, Noah Misch
Discussion: https://postgr.es/m/CA%2BhUKG%2BNBw%2BuSzxF1os-SO6gUuw%3DcqO5DAybk6KnHKzgGvxhxA%40mail.gmail.com
Discussion: https://postgr.es/m/20191222091930.GA1280238%40rfd.leadboat.com
2020-01-27 09:12:56 +13:00
Tom Lane 215824f918 In postgres_fdw, don't try to ship MULTIEXPR updates to remote server.
In a statement like "UPDATE remote_tab SET (x,y) = (SELECT ...)",
we'd conclude that the statement could be directly executed remotely,
because the sub-SELECT is in a resjunk tlist item that's not examined
for shippability.  Currently that ends up crashing if the sub-SELECT
contains any remote Vars.  Prevent the crash by deeming MULTIEXEC
Params to be unshippable.

This is a bit of a brute-force solution, since if the sub-SELECT
*doesn't* contain any remote Vars, the current execution technology
would work; but that's not a terribly common use-case for this syntax,
I think.  In any case, we generally don't try to ship sub-SELECTs, so
it won't surprise anybody that this doesn't end up as a remote direct
update.  I'd be inclined to see if that general limitation can be fixed
before worrying about this case further.

Per report from Lukáš Sobotka.

Back-patch to 9.6.  9.5 had MULTIEXPR, but we didn't try to perform
remote direct updates then, so the case didn't arise anyway.

Discussion: https://postgr.es/m/CAJif3k+iA_ekBB5Zw2hDBaE1wtiQa4LH4_JUXrrMGwTrH0J01Q@mail.gmail.com
2020-01-26 14:31:08 -05:00
Heikki Linnakangas 38a957316d Refactor XLogReadRecord(), adding XLogBeginRead() function.
The signature of XLogReadRecord() required the caller to pass the starting
WAL position as argument, or InvalidXLogRecPtr to continue reading at the
end of previous record. That's slightly awkward to the callers, as most
of them don't want to randomly jump around in the WAL stream, but start
reading at one position and then read everything from that point onwards.
Remove the 'RecPtr' argument and add a new function XLogBeginRead() to
specify the starting position instead. That's more convenient for the
callers. Also, xlogreader holds state that is reset when you change the
starting position, so having a separate function for doing that feels like
a more natural fit.

This changes XLogFindNextRecord() function so that it doesn't reset the
xlogreader's state to what it was before the call anymore. Instead, it
positions the xlogreader to the found record, like XLogBeginRead().

Reviewed-by: Kyotaro Horiguchi, Alvaro Herrera
Discussion: https://www.postgresql.org/message-id/5382a7a3-debe-be31-c860-cb810c08f366%40iki.fi
2020-01-26 11:39:00 +02:00
Tom Lane 1001368497 Clean up EXPLAIN's handling of per-worker details.
Previously, it was possible for EXPLAIN ANALYZE of a parallel query
to produce several different "Workers" fields for a single plan node,
because different portions of explain.c independently generated
per-worker data and wrapped that output in separate fields.  This
is pretty bogus, especially for the structured output formats: even
if it's not technically illegal, most programs would have a hard time
dealing with such data.

To improve matters, add infrastructure that allows redirecting
per-worker values into a side data structure, and then collect that
data into a single "Workers" field after we've finished running all
the relevant code for a given plan node.

There are a few visible side-effects:

* In text format, instead of something like

  Sort Method: external merge  Disk: 4920kB
  Worker 0:  Sort Method: external merge  Disk: 5880kB
  Worker 1:  Sort Method: external merge  Disk: 5920kB
  Buffers: shared hit=682 read=10188, temp read=1415 written=2101
  Worker 0:  actual time=130.058..130.324 rows=1324 loops=1
    Buffers: shared hit=337 read=3489, temp read=505 written=739
  Worker 1:  actual time=130.273..130.512 rows=1297 loops=1
    Buffers: shared hit=345 read=3507, temp read=505 written=744

you get

  Sort Method: external merge  Disk: 4920kB
  Buffers: shared hit=682 read=10188, temp read=1415 written=2101
  Worker 0:  actual time=130.058..130.324 rows=1324 loops=1
    Sort Method: external merge  Disk: 5880kB
    Buffers: shared hit=337 read=3489, temp read=505 written=739
  Worker 1:  actual time=130.273..130.512 rows=1297 loops=1
    Sort Method: external merge  Disk: 5920kB
    Buffers: shared hit=345 read=3507, temp read=505 written=744

* When JIT is enabled, any relevant per-worker JIT stats are attached
to the child node of the Gather or Gather Merge node, which is where
the other per-worker output has always been.  Previously, that info
was attached directly to a Gather node, or missed entirely for Gather
Merge.

* A query's summary JIT data no longer includes a bogus
"Worker Number: -1" field.

A notable code-level change is that indenting for lines of text-format
output should now be handled by calling "ExplainIndentText(es)",
instead of hard-wiring how much space to emit.  This seems a good deal
cleaner anyway.

This patch also adds a new "explain.sql" regression test script that's
dedicated to testing EXPLAIN.  There is more that can be done in that
line, certainly, but for now it just adds some coverage of the XML and
YAML output formats, which had been completely untested.

Although this is surely a bug fix, it's not clear that people would
be happy with rearranging EXPLAIN output in a minor release, so apply
to HEAD only.

Maciek Sakrejda and Tom Lane, based on an idea of Andres Freund's;
reviewed by Georgios Kokolatos

Discussion: https://postgr.es/m/CAOtHd0AvAA8CLB9Xz0wnxu1U=zJCKrr1r4QwwXi_kcQsHDVU=Q@mail.gmail.com
2020-01-25 18:16:42 -05:00
Dean Rasheed 13661ddd7e Add functions gcd() and lcm() for integer and numeric types.
These compute the greatest common divisor and least common multiple of
a pair of numbers using the Euclidean algorithm.

Vik Fearing, reviewed by Fabien Coelho.

Discussion: https://postgr.es/m/adbd3e0b-e3f1-5bbc-21db-03caf1cef0f7@2ndquadrant.com
2020-01-25 14:00:59 +00:00
Robert Haas 530609aa42 Remove jsonapi.c's lex_accept().
At first glance, this function seems useful, but it actually increases
the amount of code required rather than decreasing it. Inline the
logic into the callers instead; most callers don't use the 'lexeme'
argument for anything and as a result considerable simplification is
possible.

Along the way, fix the header comment for the nearby function
lex_expect(), which mislabeled it as lex_accept().

Patch by me, reviewed by David Steele, Mark Dilger, and Andrew
Dunstan.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com
2020-01-24 10:29:52 -08:00
Robert Haas 11b5e3e35d Split JSON lexer/parser from 'json' data type support.
Keep the code that pertains to the 'json' data type in json.c, but
move the lexing and parsing code to a new file jsonapi.c, a name
I chose because the corresponding prototypes are in jsonapi.h.

This seems like a logical division, because the JSON lexer and parser
are also used by the 'jsonb' data type, but the SQL-callable functions
in json.c are a separate thing. Also, the new jsonapi.c file needs to
include far fewer header files than json.c, which seems like a good
sign that this is an appropriate place to insert an abstraction
boundary. I took the opportunity to remove a few apparently-unneeded
includes from json.c at the same time.

Patch by me, reviewed by David Steele, Mark Dilger, and Andrew
Dunstan. The previous commit was, too, but I forgot to note it
in the commit message.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com
2020-01-24 10:17:43 -08:00
Robert Haas ce0425b162 Adjust src/include/utils/jsonapi.h so it's not backend-only.
The major change here is that we no longer include jsonb.h into
jsonapi.h. The reason that was necessary is that jsonapi.h included
several prototypes functions in jsonfuncs.c that depend on the Jsonb
type. Move those prototypes to a new header, jsonfuncs.h, and include
it where needed.

The other change is that JsonEncodeDateTime is now declared in
json.h rather than jsonapi.h.

Taken together, these steps eliminate all dependencies of jsonapi.h
on backend-only data types and header files, so that it can
potentially be included in frontend code.
2020-01-24 09:58:37 -08:00
Fujii Masao d694e0bb79 Add pg_file_sync() to adminpack extension.
This function allows us to fsync the specified file or directory.
It's useful, for example, when we want to sync the file that
pg_file_write() writes out or that COPY TO exports the data into,
for durability.

Author: Fujii Masao
Reviewed-By: Julien Rouhaud, Arthur Zakirov, Michael Paquier, Atsushi Torikoshi
Discussion: https://www.postgresql.org/message-id/CAHGQGwGY8uzZ_k8dHRoW1zDcy1Z7=5GQ+So4ZkVy2u=nLsk=hA@mail.gmail.com
2020-01-24 20:42:52 +09:00
Peter Eisentraut cc25464763 Add exclusion to headercheck
src/include/common/unicode_combining_table.h is currently not meant to
be included standalone.  Things could be refactored to allow it, but
that would be beyond the present purpose.  So adding an exclusion here
seems best.

Discussion: https://www.postgresql.org/message-id/10754.1579535012@sss.pgh.pa.us
2020-01-24 12:23:06 +01:00
Peter Eisentraut a7a848844d Fix typo 2020-01-24 12:18:07 +01:00