\crosstabview is a completely different way to display results from a
query: instead of a vertical display of rows, the data values are placed
in a grid where the column and row headers come from the data itself,
similar to a spreadsheet.
The sort order of the horizontal header can be specified by using
another column in the query, and the vertical header determines its
ordering from the order in which they appear in the query.
This only allows displaying a single value in each cell. If more than
one value correspond to the same cell, an error is thrown. Merging of
values can be done in the query itself, if necessary. This may be
revisited in the future.
Author: Daniel Verité
Reviewed-by: Pavel Stehule, Dean Rasheed
The buildfarm showed failure for Windows MSVC builds due to this
omission. This might not be the only problem with the Makefile for
this feature, but hopefully this will get it past the immediate
problem.
Fix suggested by Tom Lane
Previously bcac23d exposed a subset of support functions, namely the
ones Kaigai found useful. In
20160304193704.elq773pyg5fyl3mi@alap3.anarazel.de I mentioned that
there's some functions missing to use the facility in an external
project.
To avoid having to add functions piecemeal, add all the functions which
are used to define READ_* and WRITE_* macros; users of the extensible
node functionality are likely to need these. Additionally expose
outDatum(), which doesn't have it's own WRITE_ macro, as it needs
information from the embedding struct.
Discussion: 20160304193704.elq773pyg5fyl3mi@alap3.anarazel.de
This creates an initial set of default roles which administrators may
use to grant access to, historically, superuser-only functions. Using
these roles instead of granting superuser access reduces the number of
superuser roles required for a system. Documention for each of the
default roles has been added to user-manag.sgml.
Bump catversion to 201604082, as we had a commit that bumped it to
201604081 and another that set it back to 201604071...
Reviews by José Luis Tallón and Robert Haas
This will prevent users from creating roles which begin with "pg_" and
will check for those roles before allowing an upgrade using pg_upgrade.
This will allow for default roles to be provided at initdb time.
Reviews by José Luis Tallón and Robert Haas
This feature is controlled by a new old_snapshot_threshold GUC. A
value of -1 disables the feature, and that is the default. The
value of 0 is just intended for testing. Above that it is the
number of minutes a snapshot can reach before pruning and vacuum
are allowed to remove dead tuples which the snapshot would
otherwise protect. The xmin associated with a transaction ID does
still protect dead tuples. A connection which is using an "old"
snapshot does not get an error unless it accesses a page modified
recently enough that it might not be able to produce accurate
results.
This is similar to the Oracle feature, and we use the same SQLSTATE
and error message for compatibility.
This patch is a no-op patch which is intended to reduce the chances
of failures of omission once the functional part of the "snapshot
too old" patch goes in. It adds parameters for snapshot, relation,
and an enum to specify whether the snapshot age check needs to be
done for the page at this point. This initial patch passes NULL
for the first two new parameters and BGP_NO_SNAPSHOT_TEST for the
third. The follow-on patch will change the places where the test
needs to be made.
Pretty sure I removed this based on some incorrect thinking that it was
no longer possible to reach this point for a table which will not be
dumped, but that's clearly wrong.
Pointed out on IRC by Erik Rijkers.
These parameters are available for SSPI authentication only, to make
it possible to make it behave more like "normal gssapi", while
making it possible to maintain compatibility.
compat_realm is on by default, but can be turned off to make the
authentication use the full Kerberos realm instead of the NetBIOS name.
upn_username is off by default, and can be turned on to return the users
Kerberos UPN rather than the SAM-compatible name (a user in Active
Directory can have both a legacy SAM-compatible username and a new
Kerberos one. Normally they are the same, but not always)
Author: Christian Ullrich
Reviewed by: Robbie Harwood, Alvaro Herrera, me
Output order from the pg_indexes view might vary depending on the
phase of the moon, so add ORDER BY to ensure stable results of tests
added by commit 386e3d7609.
Per buildfarm.
OpenSSL has an unfortunate tendency to mix per-session state error
handling with per-thread error handling. This can cause problems when
programs that link to libpq with OpenSSL enabled have some other use of
OpenSSL; without care, one caller of OpenSSL may cause problems for the
other caller. Backend code might similarly be affected, for example
when a third party extension independently uses OpenSSL without taking
the appropriate precautions.
To fix, don't trust other users of OpenSSL to clear the per-thread error
queue. Instead, clear the entire per-thread queue ahead of certain I/O
operations when it appears that there might be trouble (these I/O
operations mostly need to call SSL_get_error() to check for success,
which relies on the queue being empty). This is slightly aggressive,
but it's pretty clear that the other callers have a very dubious claim
to ownership of the per-thread queue. Do this is both frontend and
backend code.
Finally, be more careful about clearing our own error queue, so as to
not cause these problems ourself. It's possibly that control previously
did not always reach SSLerrmessage(), where ERR_get_error() was supposed
to be called to clear the queue's earliest code. Make sure
ERR_get_error() is always called, so as to spare other users of OpenSSL
the possibility of similar problems caused by libpq (as opposed to
problems caused by a third party OpenSSL library like PHP's OpenSSL
extension). Again, do this is both frontend and backend code.
See bug #12799 and https://bugs.php.net/bug.php?id=68276
Based on patches by Dave Vitek and Peter Eisentraut.
From: Peter Geoghegan <pg@bowt.ie>
Create a "bsd" auth method that works the same as "password" so far as
clients are concerned, but calls the BSD Authentication service to
check the password. This is currently only available on OpenBSD.
Marisa Emerson, reviewed by Thomas Munro
This allows parallel aggregation to use them. It may seem surprising
that we use float8_combine for both float4_accum and float8_accum
transition functions, but that's because those functions differ only
in the type of the non-transition-state argument.
Haribabu Kommi, reviewed by David Rowley and Tomas Vondra
As noticed by Tom Lane changing operation's number in commit
bb140506df causes on-disk format incompatibility.
Revert to previous numbering, that is reason to add special array to store
priorities of operation. Also it reverts order of tsquery to previous.
Author: Dmitry Ivanov
Now indexes (but only B-tree for now) can contain "extra" column(s) which
doesn't participate in index structure, they are just stored in leaf
tuples. It allows to use index only scan by using single index instead
of two or more indexes.
Author: Anastasia Lubennikova with minor editorializing by me
Reviewers: David Rowley, Peter Geoghegan, Jeff Janes
Most of what is produced by the detailed verbosity level is of no
interest at all, so switch to the normal level for more usable output.
Christian Ullrich
Backpatch to all live branches
Don't try to examine S_ISLNK(st.st_mode) after a failed lstat().
It's undefined.
Also, if the lstat() reported ENOENT, we do not wish that to be a hard
error, but the code might nonetheless treat it as one (giving an entirely
misleading error message, too) depending on luck-of-the-draw as to what
S_ISLNK() returned.
Don't throw error for ENOENT from rmdir(), either. (We're not really
expecting ENOENT because we just stat'd the file successfully; but
if we're going to allow ENOENT in the symlink code path, surely the
directory code path should too.)
Generate an appropriate errcode for its-the-wrong-type-of-file complaints.
(ERRCODE_SYSTEM_ERROR doesn't seem appropriate, and failing to write
errcode() around it certainly doesn't work, and not writing an errcode
at all is not per project policy.)
Valgrind noticed the undefined S_ISLNK result; the other problems emerged
while reading the code in the area.
All of this appears to have been introduced in 8f15f74a44.
Back-patch to 9.5 where that commit appeared.
Patch adds a new, more rich, way to emit error message or exception from
PL/Pythonu code.
Author: Pavel Stehule
Reviewers: Catalin Iacob, Peter Eisentraut, Jim Nasby
Benchmarking has shown that the current number of clog buffers limits
scalability. We've previously increased the number in 33aaa139, but
that's not sufficient with a large number of clients.
We've benchmarked the cost of increasing the limit by benchmarking worst
case scenarios; testing showed that 128 buffers don't cause a
regression, even in contrived scenarios, whereas 256 does
There are a number of more complex patches flying around to address
various clog scalability problems, but this is simple enough that we can
get it into 9.6; and is beneficial even after those patches have been
applied.
It is a bit unsatisfactory to increase this in small steps every few
releases, but a better solution seems to require a rewrite of slru.c;
not something done quickly.
Author: Amit Kapila and Andres Freund
Discussion: CAA4eK1+-=18HOrdqtLXqOMwZDbC_15WTyHiFruz7BvVArZPaAw@mail.gmail.com
The code that estimates what parallel degree should be uesd for the
scan of a relation is currently rather stupid, so add a parallel_degree
reloption that can be used to override the planner's rather limited
judgement.
Julien Rouhaud, reviewed by David Rowley, James Sewell, Amit Kapila,
and me. Some further hacking by me.
The PAM_RHOST item is set to the remote IP address or host name and can
be used by PAM modules. A pg_hba.conf option is provided to choose
between IP address and resolved host name.
From: Grzegorz Sampolski <grzsmp@gmail.com>
Reviewed-by: Haribabu Kommi <kommi.haribabu@gmail.com>
We still use replacement selection for the first run of the sort only
and only when the number of tuples is relatively small. Otherwise,
the first run, and subsequent runs in all cases, are produced using
quicksort. This tends to be faster except perhaps for very small
amounts of working memory.
Peter Geoghegan, reviewed by Tomas Vondra, Jeff Janes, Mithun Cy,
Greg Stark, and me.
Contention on the relation extension lock can become quite fierce when
multiple processes are inserting data into the same relation at the same
time at a high rate. Experimentation shows the extending the relation
multiple blocks at a time improves scalability.
Dilip Kumar, reviewed by Petr Jelinek, Amit Kapila, and me.
In cases where joins use multiple columns we currently assess each join
separately causing gross mis-estimates for join cardinality.
This patch adds use of FK information for the first time into the
planner. When FKs are present and we have multi-column join information,
plan estimates will be drastically improved. Cases with multiple FKs
are handled, though partial matches are ignored currently.
Net effect is substantial performance improvements for joins in many
common cases. Additional planning time is isolated to cases that are
currently performing poorly, measured at 0.08 - 0.15 ms.
Please watch for planner performance regressions; circumstances seem
unlikely but the law of unintended consequences may apply somewhen.
Additional complex tests welcome to prove this before release.
Tests can be performed using SET enable_fkey_estimates = on | off
using scripts provided during Hackers discussions, message id:
552335D9.3090707@2ndquadrant.com
Authors: Tomas Vondra and David Rowley
Reviewed and tested by Simon Riggs, adding comments only
We shouldn't be adding roles during the regression tests as that can
cause back-to-back installcheck runs to fail and users running the
regression tests likley don't want those extra roles.
Pointed out by Tom
Extracted from pending unique-join patch, since this is a rather large
delta but it's simply moving code out into separately-accessible
subroutines.
I (tgl) did choose to add a bit more logic to rel_supports_distinctness,
so that it verifies that there's at least one potentially usable unique
index rather than just checking indexlist != NIL. Otherwise there's
no functional change here.
David Rowley
While prior to this patch the user-visible effect on the database
of any set of successfully committed serializable transactions was
always consistent with some one-at-a-time order of execution of
those transactions, the presence of declarative constraints could
allow errors to occur which were not possible in any such ordering,
and developers had no good workarounds to prevent user-facing
errors where they were not necessary or desired. This patch adds
a check for serialization failure ahead of duplicate key checking
so that if a developer explicitly (redundantly) checks for the
pre-existing value they will get the desired serialization failure
where the problem is caused by a concurrent serializable
transaction; otherwise they will get a duplicate key error.
While it would be better if the reads performed by the constraints
could count as part of the work of the transaction for
serialization failure checking, and we will hopefully get there
some day, this patch allows a clean and reliable way for developers
to work around the issue. In many cases existing code will already
be doing the right thing for this to "just work".
Author: Thomas Munro, with minor editing of docs by me
Reviewed-by: Marko Tiikkaja, Kevin Grittner
Patch introduces new text search operator (<-> or <DISTANCE>) into tsquery.
On-disk and binary in/out format of tsquery are backward compatible.
It has two side effect:
- change order for tsquery, so, users, who has a btree index over tsquery,
should reindex it
- less number of parenthesis in tsquery output, and tsquery becomes more
readable
Authors: Teodor Sigaev, Oleg Bartunov, Dmitry Ivanov
Reviewers: Alexander Korotkov, Artur Zakirov
Commit c22650cd64 sparked a discussion
about diverse interpretations of "token user" in error messages. Expel
old and new specimens of that phrase by making all GetTokenInformation()
callers report errors the way GetTokenUser() has been reporting them.
These error conditions almost can't happen, so users are unlikely to
observe this change.
Reviewed by Tom Lane and Stephen Frost.
GetTokenUser() will have reported an adequate error message. These
error conditions almost can't happen, so users are unlikely to observe
this change.
Reviewed by Tom Lane and Stephen Frost.
Now that pg_dump will properly dump out any ACL changes made to
functions which exist in pg_catalog, switch to using the GRANT system
to manage access to those functions.
This means removing 'if (!superuser()) ereport()' checks from the
functions themselves and then REVOKEing EXECUTE right from 'public' for
these functions in system_views.sql.
Reviews by Alexander Korotkov, Jose Luis Tallon
Now that all of the infrastructure exists, add in the ability to
dump out the ACLs of the objects inside of pg_catalog or the ACLs
for objects which are members of extensions, but only if they have
been changed from their original values.
The original values are tracked in pg_init_privs. When pg_dump'ing
9.6-and-above databases, we will dump out the ACLs for all objects
in pg_catalog and the ACLs for all extension members, where the ACL
has been changed from the original value which was set during either
initdb or CREATE EXTENSION.
This should not change dumps against pre-9.6 databases.
Reviews by Alexander Korotkov, Jose Luis Tallon
Historically, the "dump" component of the namespace has been used
to decide if the objects inside of the namespace should be dumped
also. Given that "dump" is now a bitmask and may be partial, and
we may want to dump out all components of the namespace object but
only some of the components of objects contained in the namespace,
create a "dump_contains" bitmask which will represent what components
of the objects inside of a namespace should be dumped out.
No behavior change here, but in preparation for a change where we
will dump out just the ACLs of objects in pg_catalog, but we might
not dump out the ACL of the pg_catalog namespace itself (for instance,
when it hasn't been changed from the value set at initdb time).
Reviews by Alexander Korotkov, Jose Luis Tallon
pg_dump has historically used a simple boolean 'dump' value to indicate
if a given object should be included in the dump or not. Instead, use
a bitmap which breaks down the components of an object into their
distinct pieces and use that bitmap to only include the components
requested.
This does not include any behavioral change, but is in preperation for
the change to dump out just ACLs for objects in pg_catalog.
Reviews by Alexander Korotkov, Jose Luis Tallon
This new catalog holds the privileges which the system was
initialized with at initdb time, along with any permissions set
by extensions at CREATE EXTENSION time. This allows pg_dump
(and any other similar use-cases) to detect when the privileges
set on initdb-created or extension-created objects have been
changed from what they were set to at initdb/extension-creation
time and handle those changes appropriately.
Reviews by Alexander Korotkov, Jose Luis Tallon
It inserts a new value into an jsonb array at arbitrary position or
a new key to jsonb object.
Author: Dmitry Dolgov
Reviewers: Petr Jelinek, Vitaly Burovoy, Andrew Dunstan
Some object types have names that are only unique for one table. But
for those we generally didn't put the table name into the dump TOC tag.
So it was impossible to identify these objects if the same name was used
for multiple tables. This affects policies, column defaults,
constraints, triggers, and rules.
Fix by adding the table name to the TOC tag, so that it now reads
"$schema $table $object".
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
API and mechanism to allow generic messages to be inserted into WAL that are
intended to be read by logical decoding plugins. This commit adds an optional
new callback to the logical decoding API.
Messages are either text or bytea. Messages can be transactional, or not, and
are identified by a prefix to allow multiple concurrent decoding plugins.
(Not to be confused with Generic WAL records, which are intended to allow crash
recovery of extensible objects.)
Author: Petr Jelinek and Andres Freund
Reviewers: Artur Zakirov, Tomas Vondra, Simon Riggs
Discussion: 5685F999.6010202@2ndquadrant.com
Previously synchronous replication offered only the ability to confirm
that all changes made by a transaction had been transferred to at most
one synchronous standby server.
This commit extends synchronous replication so that it supports multiple
synchronous standby servers. It enables users to consider one or more
standby servers as synchronous, and increase the level of transaction
durability by ensuring that transaction commits wait for replies from
all of those synchronous standbys.
Multiple synchronous standby servers are configured in
synchronous_standby_names which is extended to support new syntax of
'num_sync ( standby_name [ , ... ] )', where num_sync specifies
the number of synchronous standbys that transaction commits need to
wait for replies from and standby_name is the name of a standby
server.
The syntax of 'standby_name [ , ... ]' which was used in 9.5 or before
is also still supported. It's the same as new syntax with num_sync=1.
This commit doesn't include "quorum commit" feature which was discussed
in pgsql-hackers. Synchronous standbys are chosen based on their priorities.
synchronous_standby_names determines the priority of each standby for
being chosen as a synchronous standby. The standbys whose names appear
earlier in the list are given higher priority and will be considered as
synchronous. Other standby servers appearing later in this list
represent potential synchronous standbys.
The regression test for multiple synchronous standbys is not included
in this commit. It should come later.
Authors: Sawada Masahiko, Beena Emerson, Michael Paquier, Fujii Masao
Reviewed-By: Kyotaro Horiguchi, Amit Kapila, Robert Haas, Simon Riggs,
Amit Langote, Thomas Munro, Sameer Thakur, Suraj Kharage, Abhijit Menon-Sen,
Rajeev Rastogi
Many thanks to the various individuals who were involved in
discussing and developing this feature.
This introduces a new dependency type which marks an object as depending
on an extension, such that if the extension is dropped, the object
automatically goes away; and also, if the database is dumped, the object
is included in the dump output. Currently the grammar supports this for
indexes, triggers, materialized views and functions only, although the
utility code is generic so adding support for more object types is a
matter of touching the parser rules only.
Author: Abhijit Menon-Sen
Reviewed-by: Alexander Korotkov, Álvaro Herrera
Discussion: http://www.postgresql.org/message-id/20160115062649.GA5068@toroid.org
has_parallel_hazard() was ignoring the proparallel markings for
aggregates, which is no good. Fix that. There was no way to mark
an aggregate as actually being parallel-safe, either, so add a
PARALLEL option to CREATE AGGREGATE.
Patch by me, reviewed by David Rowley.
Experimentation shows this only costs about 6kB, which seems well
worth it given the major performance effects that can be caused
by insufficient alignment, especially on larger systems.
Discussion: 14166.1458924422@sss.pgh.pa.us
PL/Python failed if a PL/Python function was invoked recursively via SPI,
since arguments are passed to the function in its global dictionary
(a horrible decision that's far too ancient to undo) and it would delete
those dictionary entries on function exit, leaving the outer recursion
level(s) without any arguments. Not deleting them would be little better,
since the outer levels would then see the innermost level's arguments.
Since PL/Python uses ValuePerCall mode for evaluating set-returning
functions, it's possible for multiple executions of the same SRF to be
interleaved within a query. PL/Python failed in such a case, because
it stored only one iterator per function, directly in the function's
PLyProcedure struct. Moreover, one interleaved instance of the SRF
would see argument values that should belong to another.
Hence, invent code for saving and restoring the argument entries. To fix
the recursion case, we only need to save at recursive entry and restore
at recursive exit, so the overhead in non-recursive cases is negligible.
To fix the SRF case, we have to save when suspending a SRF and restore
when resuming it, which is potentially not negligible; but fortunately
this is mostly a matter of manipulating Python object refcounts and
should not involve much physical data copying.
Also, store the Python iterator and saved argument values in a structure
associated with the SRF call site rather than the function itself. This
requires adding a memory context deletion callback to ensure that the SRF
state is cleaned up if the calling query exits before running the SRF to
completion. Without that we'd leak a refcount to the iterator object in
such a case, resulting in session-lifespan memory leakage. (In the
pre-existing code, there was no memory leak because there was only one
iterator pointer, but what would happen is that the previous iterator
would be resumed by the next query attempting to use the SRF. Hardly the
semantics we want.)
We can buy back some of whatever overhead we've added by getting rid of
PLy_function_delete_args(), which seems a useless activity: there is no
need to delete argument entries from the global dictionary on exit,
since the next time anyone would see the global dict is on the next
fresh call of the PL/Python function, at which time we'd overwrite those
entries with new arg values anyway.
Also clean up some really ugly coding in the SRF implementation, including
such gems as returning directly out of a PG_TRY block. (The only reason
that failed to crash hard was that all existing call sites immediately
exited their own PG_TRY blocks, popping the dangling longjmp pointer before
there was any chance of it being used.)
In principle this is a bug fix; but it seems a bit too invasive relative to
its value for a back-patch, and besides the fix depends on memory context
callbacks so it could not go back further than 9.5 anyway.
Alexey Grishchenko and Tom Lane
This lets us use parallel aggregate for a variety of useful cases
that didn't work before, like sum(int8), sum(numeric), several
versions of avg(), and various other functions.
Add some regression tests, as well, testing the general sanity of
these and future catalog entries.
David Rowley, reviewed by Tomas Vondra, with a few further changes
by me.
Previously non-exclusive backups had to be done using the replication protocol
and pg_basebackup. With this commit it's now possible to make them using
pg_start_backup/pg_stop_backup as well, as long as the backup program can
maintain a persistent connection to the database.
Doing this, backup_label and tablespace_map are returned as results from
pg_stop_backup() instead of being written to the data directory. This makes
the server safe from a crash during an ongoing backup, which can be a problem
with exclusive backups.
The old syntax of the functions remain and work exactly as before, but since the
new syntax is safer this should eventually be deprecated and removed.
Only reference documentation is included. The main section on backup still needs
to be rewritten to cover this, but since that is already scheduled for a separate
large rewrite, it's not included in this patch.
Reviewed by David Steele and Amit Kapila
As noted by Julian Schauder in bug #14063, the configuration-file parser
doesn't support embedded newlines in string literals. While there might
someday be a good reason to remove that restriction, there doesn't seem
to be one right now. However, ALTER SYSTEM SET could accept strings
containing newlines, since many of the variable-specific value-checking
routines would just see a newline as whitespace. This led to writing a
postgresql.auto.conf file that was broken and had to be removed manually.
Pending a reason to work harder, just throw an error if someone tries this.
In passing, fix several places in the ALTER SYSTEM logic that failed to
provide an errcode() for an ereport(), and thus would falsely log the
failure as an internal XX000 error.
Back-patch to 9.4 where ALTER SYSTEM was introduced.
Alex Shulgin complained that the underlying strategy wasn't all that
apparent, particularly not the fact that we intentionally have two
code paths depending on whether we think the column has a limited set
of possible values or not. Try to make it clearer.
On reflection, the pre-existing logic in ANALYZE is specifically meant to
compare the frequency of a candidate MCV against the estimated frequency of
a random distinct value across the whole table. The change to compare it
against the average frequency of values actually seen in the sample doesn't
seem very principled, and if anything it would make us less likely not more
likely to consider a value an MCV. So revert that, but keep the aspect of
considering only nonnull values, which definitely is correct.
In passing, rename the local variables in these stanzas to
"ndistinct_table", to avoid confusion with the "ndistinct" that appears at
an outer scope in compute_scalar_stats.
\gexec executes the just-entered query, like \g, but instead of printing
the results it takes each field as a SQL command to send to the server.
Computing a series of queries to be executed is a fairly common thing,
but up to now you always had to resort to kluges like writing the queries
to a file and then inputting the file. Now it can be done with no
intermediate step.
The implementation is fairly straightforward except for its interaction
with FETCH_COUNT. ExecQueryUsingCursor isn't capable of being called
recursively, and even if it were, its need to create a transaction
block interferes unpleasantly with the desired behavior of \gexec after
a failure of a generated query (i.e., that it can continue). Therefore,
disable use of ExecQueryUsingCursor when doing the master \gexec query.
We can still apply it to individual generated queries, however, and there
might be some value in doing so.
While testing this feature's interaction with single-step mode, I (tgl) was
led to conclude that SendQuery needs to recognize SIGINT (cancel_pressed)
as a negative response to the single-step prompt. Perhaps that's a
back-patchable bug fix, but for now I just included it here.
Corey Huinker, reviewed by Jim Nasby, Daniel Vérité, and myself
This elevel is useful for logging audit messages and similar information
that should not be passed to the client. It's equivalent to LOG in terms
of decisions about logging priority in the postmaster log, but messages
with this elevel will never be sent to the client.
In the current implementation, it's just an alias for the longstanding
COMMERROR elevel (or more accurately, we've made COMMERROR an alias for
this). At some point it might be interesting to allow a LOG_ONLY flag to
be attached to any elevel, but that would be considerably more complicated,
and it's not clear there's enough use-cases to justify the extra work.
For now, let's just take the easy 90% solution.
David Steele, reviewed by Fabien Coelho, Petr Jelínek, and myself
The first iteration of the signal-checking loop would compute sigmask(0)
which expands to 1<<(-1) which is undefined behavior according to the
C standard. The lack of field reports of trouble suggest that it
evaluates to 0 on all existing Windows compilers, but that's hardly
something to rely on. Since signal 0 isn't a queueable signal anyway,
we can just make the loop iterate from 1 instead, and save a few cycles
as well as avoiding the undefined behavior.
In passing, avoid evaluating the volatile expression UNBLOCKED_SIGNAL_QUEUE
twice in a row; there's no reason to waste cycles like that.
Noted by Aleksander Alekseev, though this isn't his proposed fix.
Back-patch to all supported branches.
When adjusting the estimate for the number of distinct values from a
rel in a grouped query to take into account the selectivity of the
rel's restrictions, use a formula that is less likely to produce
under-estimates.
The old formula simply multiplied the number of distinct values in the
rel by the restriction selectivity, which would be correct if the
restrictions were fully correlated with the grouping expressions, but
can produce significant under-estimates in cases where they are not
well correlated.
The new formula is based on the random selection probability, and so
assumes that the restrictions are not correlated with the grouping
expressions. This is guaranteed to produce larger estimates, and of
course risks over-estimating in cases where the restrictions are
correlated, but that has less severe consequences than
under-estimating, which might lead to a HashAgg that consumes an
excessive amount of memory.
This could possibly be improved upon in the future by identifying
correlated restrictions and using a hybrid of the old and new
formulae.
Author: Tomas Vondra, with some hacking be me
Reviewed-by: Mark Dilger, Alexander Korotkov, Dean Rasheed and Tom Lane
Discussion: http://www.postgresql.org/message-id/flat/56CD0381.5060502@2ndquadrant.com
If archive_timeout > 0 we should avoid logging XLOG_RUNNING_XACTS if idle.
Bug 13685 reported by Laurence Rowe, investigated in detail by Michael Paquier,
though this is not his proposed fix.
20151016203031.3019.72930@wrigleys.postgresql.org
Simple non-invasive patch to allow later backpatch to 9.4 and 9.5
Replay of XLOG_BTREE_VACUUM during Hot Standby was previously thought to require
complex interlocking that matched the requirements on the master. This required
an O(N) operation that became a significant problem with large indexes, causing
replication delays of seconds or in some cases minutes while the
XLOG_BTREE_VACUUM was replayed.
This commit skips the pin scan that was previously required, by observing in
detail when and how it is safe to do so, with full documentation. The pin
scan is skipped only in replay; the VACUUM code path on master is not
touched here and WAL is identical.
The current commit applies in all cases, effectively replacing commit
687f2cd7a0.
Often, upon getting an unexpected error in psql, one's first wish is that
the verbosity setting had been higher; for example, to be able to see the
schema-name field or the server code location info. Up to now the only way
has been to adjust the VERBOSITY variable and repeat the failing query.
That's a pain, and it doesn't work if the error isn't reproducible.
This commit adds a psql feature that redisplays the most recent server
error at full verbosity, without needing to make any variable changes or
re-execute the failed command. We just need to hang onto the latest error
PGresult in case the user executes \errverbose, and then apply libpq's
new PQresultVerboseErrorMessage() function to it. This will consume
some trivial amount of psql memory, but otherwise the cost when the
feature isn't used should be negligible.
Alex Shulgin, reviewed by Daniel Vérité, some improvements by me
Often, upon getting an unexpected error in psql, one's first wish is that
the verbosity setting had been higher; for example, to be able to see the
schema-name field or the server code location info. Up to now the only way
has been to adjust the VERBOSITY variable and repeat the failing query.
That's a pain, and it doesn't work if the error isn't reproducible.
This commit adds support in libpq for regenerating the error message for
an existing error PGresult at any desired verbosity level. This is almost
just a matter of refactoring the existing code into a subroutine, but there
is one bit of possibly-needed information that was not getting put into
PGresults: the text of the last query sent to the server. We must add that
string to the contents of an error PGresult. But we only need to save it
if it might be used, which with the existing error-formatting code only
happens if there is a PG_DIAG_STATEMENT_POSITION error field, which is
probably pretty rare for errors in production situations. So really the
overhead when the feature isn't used should be negligible.
Alex Shulgin, reviewed by Daniel Vérité, some improvements by me
Some buildfarm members are showing "comparison is always false due to
limited range of data type" complaints on this test, so #ifdef it out
on machines with 32-bit int.
As with the previous patch, large numbers of null rows could skew this
calculation unfavorably, causing us to discard values that have a
legitimate claim to be MCVs, since our definition of MCV is that it's
most common among the non-null population of the column. Hence, make
the numerator of avgcount be the number of non-null sample values not
the number of sample rows; likewise for maxmincount in the
compute_scalar_stats variant.
Also, make the denominator be the number of distinct values actually
observed in the sample, rather than reversing it back out of the computed
stadistinct. This avoids depending on the accuracy of the Haas-Stokes
approximation, and really it's what we want anyway; the threshold should
depend only on what we see in the sample, not on what we extrapolate
about the contents of the whole column.
Alex Shulgin, reviewed by Tomas Vondra and myself
Previously, we included null rows in the values of n and N that went
into the formula, which amounts to considering null as a value in its
own right; but the d and f1 values do not include nulls. This is
inconsistent, and it contributes to significant underestimation of
ndistinct when the column is mostly nulls. In any case stadistinct
is defined as the number of distinct non-null values, so we should
exclude nulls when doing this computation.
This is an aboriginal bug in our application of the Haas-Stokes formula,
but we'll refrain from back-patching for fear of destabilizing plan
choices in released branches.
While at it, make the code a bit more readable by omitting unnecessary
casts and intermediate variables.
Observation and original patch by Tomas Vondra, adjusted to fix both
uses of the formula by Alex Shulgin, cosmetic improvements by me
In the test_slot_timelines test module, we were abusing passing NULL
values which was received as zeroes in x86, but this breaks in ARM
(buildfarm member hamster) by crashing instead. Fix the breakage by
marking these functions as STRICT; the InvalidXid value that was
previously implicit in NULL values (on x86 at least) can now be passed
as 0. Failing to follow the fmgr protocol to check for NULLs beforehand
was causing ARM to fail, as evidenced by segmentation faults in
buildfarm member hamster.
In order to use the new functionality in the test script, use COALESCE
in the right spot to avoid forwarding NULL values.
This was diagnosed from the hamster crash by Craig Ringer, who also
proposed a different patch (checking for NULL values explicitely in the
C function code, and keeping the non-strictness in the C functions).
I decided to go with this approach instead.
Our actual convention, contrary to what I said in 59a2111b23, is not to
quote type names, as evidenced by unquoted use of format_type_be()
result value in error messages. Remove quotes from recently tweaked
messages accordingly.
Per note from Tom Lane
Commit acdf2a8b added a test case involving minus zero as a box endpoint.
This is not very portable, as evidenced by the several older buildfarm
members that are failing on the test because they print minus zero as
just "0". If there were any significant reason to test this behavior,
we could consider carrying a separate expected-file; but it doesn't look
to me like there's adequate justification to accept such a maintenance
burden. Just change the test to use plain zero, instead.
When getParamDescriptions was changed to handle out-of-memory better
by cribbing error recovery logic from getRowDescriptions/getAnotherTuple,
somebody omitted to copy the stanza about checking for excess data in
the message. But you need to do that, since continue'ing out of the
switch in pqParseInput3 means no such check gets applied there anymore.
Noted while looking at Michael Paquier's patch that made yet another
copy of this advance_and_error logic.
(This whole business desperately needs refactoring, because I sure don't
want to see a dozen copies of this code, but that's where we seem to be
headed. What's more, the "suspend parsing on EOF return" convention is a
holdover from protocol 2 and shouldn't exist at all in protocol 3, because
we don't process partial messages anymore. But for now, just fix the
obvious bug.)
Also, fix some wrong/missing comments about what the API spec is
for these three functions.
This doesn't seem worthy of back-patching, even though it's a bug;
the case shouldn't ever arise in the field.
This interface is designed to give an access to WAL for extensions which
could implement new access method, for example. Previously it was
impossible because restoring from custom WAL would need to access system
catalog to find a redo custom function. This patch suggests generic way
to describe changes on page with standart layout.
Bump XLOG_PAGE_MAGIC because of new record type.
Author: Alexander Korotkov with a help of Petr Jelinek, Markus Nullmeier and
minor editorization by my
Reviewers: Petr Jelinek, Alvaro Herrera, Teodor Sigaev, Jim Nasby,
Michael Paquier
I should have remembered that we can't use INT64_MODIFIER with sscanf():
configure chooses that to work with snprintf(), but it might be for our
src/port/snprintf.c implementation and so not compatible with the
platform's sscanf(). This appears to be the explanation for buildfarm
member frogmouth's continuing unhappiness with the tzcode update.
Fortunately, in all of the places where zic is attempting to read into
an int64 variable, it's reading a year which certainly will fit just fine
into an int. So make it read into an int with %d, and then cast or copy
as necessary.
Previously this test was relying too much on WAL replay to occur in the
exact configured interval, which was unreliable on slow or overly busy
servers. Use a custom loop instead of poll_query_until, which is
hopefully more reliable.
Per continued failures on buildfarm member hamster (which is probably
the only one running this test suite)
Author: Michaël Paquier
Previously, the planner would reject an index-only scan if any restriction
clause for its table used a column not available from the index, even
if that restriction clause would later be dropped from the plan entirely
because it's implied by the index's predicate. This is a fairly common
situation for partial indexes because predicates using columns not included
in the index are often the most useful kind of predicate, and we have to
duplicate (or at least imply) the predicate in the WHERE clause in order
to get the index to be considered at all. So index-only scans were
essentially unavailable with such partial indexes.
To fix, we have to do detection of implied-by-predicate clauses much
earlier in the planner. This patch puts it in check_index_predicates
(nee check_partial_indexes), meaning it gets done for every partial index,
whereas we previously only considered this issue at createplan time,
so that the work was only done for an index actually selected for use.
That could result in a noticeable planning slowdown for queries against
tables with many partial indexes. However, testing suggested that there
isn't really a significant cost, especially not with reasonable numbers
of partial indexes. We do get a small additional benefit, which is that
cost_index is more accurate since it correctly discounts the evaluation
cost of clauses that will be removed. We can also avoid considering such
clauses as potential indexquals, which saves useless matching cycles in
the case where the predicate columns aren't in the index, and prevents
generating bogus plans that double-count the clause's selectivity when
the columns are in the index.
Tomas Vondra and Kyotaro Horiguchi, reviewed by Kevin Grittner and
Konstantin Knizhnik, and whacked around a little by me
When decoding from a logical slot, it's necessary for xlog reading to be
able to read xlog from historical (i.e. not current) timelines;
otherwise, decoding fails after failover, because the archives are in
the historical timeline. This is required to make "failover logical
slots" possible; it currently has no other use, although theoretically
it could be used by an extension that creates a slot on a standby and
continues to replay from the slot when the standby is promoted.
This commit includes a module in src/test/modules with functions to
manipulate the slots (which is not otherwise possible in SQL code) in
order to enable testing, and a new test in src/test/recovery to ensure
that the behavior is as expected.
Author: Craig Ringer
Reviewed-By: Oleksii Kliukin, Andres Freund, Petr Jelínek
Some minor tweaks and comment additions, for cleanliness sake and to
avoid having the upcoming timeline-following patch be polluted with
unrelated cleanup.
Extracted from a larger patch by Craig Ringer, reviewed by Andres
Freund, with some additions by myself.
Formerly, the geometric I/O routines such as box_in and point_out relied
directly on strtod() and sprintf() for conversion of the float8 component
values of their data types. However, the behavior of those functions is
pretty platform-dependent, especially for edge-case values such as
infinities and NaNs. This was exposed by commit acdf2a8b37, which
added test cases involving boxes with infinity endpoints, and immediately
failed on Windows and AIX buildfarm members. We solved these problems
years ago in the main float8in and float8out functions, so let's fix it
by making the geometric types use that code instead of depending directly
on the platform-supplied functions.
To do this, refactor the float8in code so that it can be used to parse
just part of a string, and as a convenience make the guts of float8out
usable without going through DirectFunctionCall.
While at it, get rid of geo_ops.c's fairly shaky assumptions about the
maximum output string length for a double, by having it build results in
StringInfo buffers instead of fixed-length strings.
In passing, convert all the "invalid input syntax for type foo" messages
in this area of the code into "invalid input syntax for type %s" to reduce
the number of distinct translatable strings, per recent discussion.
We would have needed a fair number of the latter anyway for code-sharing
reasons, so we might as well just go whole hog.
Note: this patch is by no means intended to guarantee that the geometric
types uniformly behave sanely for infinity or NaN component values.
But any bugs we have in that line were there all along, they were just
harder to reach in a platform-independent way.
My compiler doesn't like the lack of initialization of "flag", and
I think it's right: if there were zero keys we'd have an undefined
result. The AND of zero items is TRUE, so initialize to TRUE.
Patch implements quad-tree over boxes, naive approach of 2D quad tree will not
work for any non-point objects because splitting space on node is not
efficient. The idea of pathc is treating 2D boxes as 4D points, so,
object will not overlap (in 4D space).
The performance tests reveal that this technique especially beneficial
with too much overlapping objects, so called "spaghetti data".
Author: Alexander Lebedev with editorization by Emre Hasegeli and me
During scan sometimes it would be very helpful to know some information about
parent node or all ancestor nodes. Right now reconstructedValue could be used
but it's not a right usage of it (range opclass uses that).
traversalValue is arbitrary piece of memory in separate MemoryContext while
reconstructedVale should have the same type as indexed column.
Subsequent patches for range opclass and quad4d tree will use it.
Author: Alexander Lebedev, Teodor Sigaev
Reporting the specific out-of-range input value produces platform-dependent
results. We could skip reporting the value, but that's contrary to our
message style guidelines and unhelpful to users. Or we could add a
separate expected-output file for Windows, but that would be a substantial
maintenance burden, and these test cases seem unlikely to be worth it.
Per buildfarm.
In this mode, the master waits for the transaction to be applied on
the remote side, not just written to disk. That means that you can
count on a transaction started on the standby to see all commits
previously acknowledged by the master.
To make this work, the standby sends a reply after replaying each
commit record generated with synchronous_commit >= 'remote_apply'.
This introduces a small inefficiency: the extra replies will be sent
even by standbys that aren't the current synchronous standby. But
previously-existing synchronous_commit levels make no attempt at all
to optimize which replies are sent based on what the primary cares
about, so this is no worse, and at least avoids any extra replies for
people not using the feature at all.
Thomas Munro, reviewed by Michael Paquier and by me. Some additional
tweaks by me.
interval_mul() attempts to prevent its calculations from producing silly
results, but it forgot that zero times infinity yields NaN in IEEE
arithmetic. Hence, a case like '1 second'::interval * 'infinity'::float8
produced a NaN for the months product, which didn't trigger the range
check, resulting in bogus and possibly platform-dependent output.
This isn't terribly obvious to the naked eye because if you try that
exact case, you get "interval out of range" which is what you expect
--- but if you look closer, the error is coming from interval_out not
interval_mul. interval_mul has allowed a bogus value into the system.
Fix by adding isnan tests.
Noted while testing Vitaly Burovoy's fix for infinity input to
to_timestamp(). Given the lack of field complaints, I doubt this
is worth a back-patch.
With the original SQL-function implementation, such cases failed because
we don't support infinite intervals. Converting the function to C lets
us bypass the interval representation, which should be a bit faster as
well as more flexible.
Vitaly Burovoy, reviewed by Anastasia Lubennikova
resulttypeLen and resulttypeByVal must be set correctly when serializing
aggregates, not just when finalizing them. This was in David's final
patch but I downloaded the wrong version by mistake and failed to spot
the error.
David Rowley
This is necessary infrastructure for supporting parallel aggregation
for aggregates whose transition type is "internal". Such values
can't be passed between cooperating processes, because they are
just pointers.
David Rowley, reviewed by Tomas Vondra and by me.
This refines the previous weight range and allows a script to be "turned
off" by passing a zero weight, which is useful when scripting multiple
pgbench runs.
I did not apply the suggested warning when a script uses zero weight; we
use the principle elsewhere that if there's nothing to be done, do
nothing quietly.
Adjust docs accordingly.
Author: Jeff Janes, Fabien Coelho
You can now do the same thing via \set using the appropriate function,
either random(), random_gaussian(), or random_exponential(), depending
on the desired distribution. This is not backward-compatible, but per
discussion, it's worth it to avoid having the old syntax hang around
forever.
Fabien Coelho, reviewed by Michael Paquier, and adjusted by me.
Whenever this function is used with the FORMAT_MESSAGE_FROM_SYSTEM flag,
it's good practice to include FORMAT_MESSAGE_IGNORE_INSERTS as well.
Otherwise, if the message contains any %n insertion markers, the function
will try to fetch argument strings to substitute --- which we are not
passing, possibly leading to a crash. This is exactly analogous to the
rule about not giving printf() a format string you're not in control of.
Noted and patched by Christian Ullrich.
Back-patch to all supported branches.
When tsearch was implemented I did several mistakes in hostname/email
definition rules:
1) allow underscore in hostname what prohibited by RFC
2) forget to allow leading digits separated by hyphen (like 123-x.com)
in hostname
3) do no allow underscore/hyphen after leading digits in localpart of email
Artur's patch resolves two last issues, but by the way allows hosts name like
123_x.com together with 123-x.com. RFC forbids underscore usage in hostname
but pg allows that since initial tsearch version in core, although only
for non-digits. Patch syncs support digits and nondigits in both hostname and
email.
Forbidding underscore in hostname may break existsing usage of tsearch and,
anyhow, it should be done by separate patch.
Author: Artur Zakirov
BUG: #13964
Per discussion, the new extensible node framework is thought to be
better designed than the custom path/scan/scanstate stuff we added
in PostgreSQL 9.5. Rework the latter to be more like the former.
This is not backward-compatible, but we generally don't promise that
for C APIs, and there probably aren't many people using this yet
anyway.
KaiGai Kohei, reviewed by Petr Jelinek and me. Some further
cosmetic changes by me.
The IANA crew seem to think that symlink() exists everywhere nowadays,
and they may well be right. But we use #ifdef HAVE_SYMLINK elsewhere
so for consistency we should do it here too. Noted by Michael Paquier.
The new coding of dolink() is dependent on link() returning an on-point
errno when it fails; but the quick-hack implementation of link() that
we'd put in for Windows didn't bother with setting errno. Fix that.
Analysis and patch by Christian Ullrich.
INT64_MIN/MAX should be spelled PG_INT64_MIN/MAX, per well established
convention in our sources. Less obviously, a symbol named DOUBLE causes
problems on Windows builds, so rename that to DOUBLE_CONST; and rename
INTEGER to INTEGER_CONST for consistency.
Also, get rid of incorrect/obsolete hand-munging of yycolumn, and fix
the grammar for float constants to handle expected cases such as ".1".
First two items by Michael Paquier, second two by me.
Commit fbe5a3fb73 accidentally changed
this behavior; put things back the way they were, and add some
regression tests.
Report by Andres Freund; patch by Ashutosh Bapat, with a bit of
kibitzing by me.
Up until now, we've been using timezone and tzname, but Visual Studio
2015 (for which we wish to add support) no longer declares those
symbols. All versions since Visual Studio 2003 apparently support the
underscore-equipped names, and we don't support anything older than
Visual Studio 2005, so this should work OK everywhere. But let's see
what the buildfarm thinks.
Michael Paquier, reviewed by Petr Jelinek
The new functions are pi(), random(), random_exponential(),
random_gaussian(), and sqrt(). I was worried that this would be
slower than before, but, if anything, it actually turns out to be
slightly faster, because we now express the built-in pgbench scripts
using fewer lines; each \setrandom can be merged into a subsequent
\set.
Fabien Coelho
Corrects an oversight in 2c83f435a3 where the $timed_out reference var
isn't initialized; using it would require the caller to initialize it
beforehand, which is cumbersome.
Author: Craig Ringer
This brings us a bit closer to matching upstream, but since it affects
files outside src/timezone/, we might choose not to back-patch it.
Hence keep it separate from the main update patch.
We hadn't done this in about six years, which proves to have been a mistake
because there's been a lot of code churn upstream, making the merge rather
painful. But putting it off any further isn't going to lessen the pain,
and there are at least two incompatible changes that we need to absorb
before someone starts complaining that --with-system-tzdata doesn't work
at all on their platform, or we get blindsided by a tzdata release that
our out-of-date zic can't compile. Last week's "time zone abbreviation
differs from POSIX standard" mess was a wake-up call in that regard.
This is a sufficiently large patch that I'm afraid to back-patch it
immediately, though the foregoing considerations imply that we probably
should do so eventually. For the moment, just put it in HEAD so that
it can get some testing. Maybe we can wait till the end of the 9.6
beta cycle before deeming it okay.
Change the slightly different variations of the message
function FOO must return type BAR
to a single wording, removing the variability in type name so that they
all create a single translation entry; since the type name is not to be
translated, there's no point in it being part of the message anyway.
Also, change them all to use the same quoting convention, namely that
the function name is not to be quoted but the type name is. (I'm not
quite sure why this is so, but it's the clear majority.)
Some similar messages such as "encoding conversion function FOO must ..."
are also changed.
In the plancache, we check if the environment we planned the query under
has changed in a way which requires us to re-plan, such as when the user
for whom the plan was prepared changes and RLS is being used (and,
therefore, there may be different policies to apply).
Unfortunately, while those values were set and checked, they were not
being reset when the query was re-planned and therefore, in cases where
we change role, re-plan, and then change role again, we weren't
re-planning again. This leads to potentially incorrect policies being
applied in cases where role-specific policies are used and a given query
is planned under one role and then executed under other roles, which
could happen under security definer functions or when a common user and
query is planned initially and then re-used across multiple SET ROLEs.
Further, extensions which made use of CopyCachedPlan() may suffer from
similar issues as the RLS-related fields were not properly copied as
part of the plan and therefore RevalidateCachedQuery() would copy in the
current settings without invalidating the query.
Fix by using the same approach used for 'search_path', where we set the
correct values in CompleteCachedPlan(), check them early on in
RevalidateCachedQuery() and then properly reset them if re-planning.
Also, copy through the values during CopyCachedPlan().
Pointed out by Ashutosh Bapat. Reviewed by Michael Paquier.
Back-patch to 9.5 where RLS was introduced.
Security: CVE-2016-2193
Fix up check for high-bit-set characters, which provoked "comparison is
always true due to limited range of data type" warnings on some compilers,
and was unlike the way we do it elsewhere anyway. Fix omission of "$"
from the set of valid identifier continuation characters. Get rid of
sanitize_text(), which was utterly inconsistent with any other error report
anywhere in the system, and wasn't even well designed on its own terms
(double-quoting the result string without escaping contained double quotes
doesn't seem very well thought out). Fix up error messages, which didn't
follow the message style guidelines very well, and were overly specific in
situations where the actual mistake might not be what they said. Improve
documentation.
(I started out just intending to fix the compiler warning, but the more
I looked at the patch the less I liked it.)
If the referenced rel was proven empty, we'd compute 0/0 here, which
results in the function returning NaN. That's a bit more serious
than the other zero-divide case. Still, it only seems to be possible
in HEAD, so no back-patch.
Per report from Piotr Stefaniak. I looked through the rest of selfuncs.c
and found no other likely trouble spots.
This avoids a possible divide-by-zero in the following calculation,
and rounding the number to an integer seems like saner behavior anyway.
Assuming IEEE math, the division would yield +Infinity which would get
replaced by 1.0 at the bottom of the function, so nothing really
interesting would ensue; but avoiding divide-by-zero seems like a
good idea on general principles.
Per report from Piotr Stefaniak. No back-patch since this seems
mostly cosmetic.
Previously pg_rewind did not fsync any files. That's problematic, given
that the target directory is modified. If the database was started
afterwards, 2ce439f33 luckily already caused the data directory to be
synced to disk at postmaster startup; reducing the scope of the problem.
To fix, use initdb -S, at the end of the pg_rewind run. It doesn't seem
worthwhile to duplicate the code into pg_rewind, and initdb -S is
already used that way by pg_upgrade.
Reported-By: Andres Freund
Author: Michael Paquier, somewhat edited by me
Discussion: 20160310034352.iuqgvpmg5qmnxtkz@alap3.anarazel.deCAB7nPqSytVG1o4S3S2pA1O=692ekurJ+fckW2PywEG3sNw54Ow@mail.gmail.com
Backpatch: 9.5, where pg_rewind was introduced
This was a relatively harmless leak, as createBackupLabel() is only
called once per pg_rewind invocation.
Author: Michael Paquier
Reported-By: Michael Paquier
Discussion: CAB7nPqRnOw30gOXe2_SPLjh37bgm4V+txbYAPwoXb97nGQ297w@mail.gmail.com
Backpatch: 9.5, where pg_rewind was introduced
Returning the direct result of bit arithmetic, in a macro intended to be
used in a boolean manner, can be problematic if the return value is
stored in a variable of type 'bool'. If bool is implemented using C99's
_Bool, that can lead to comparison failures if the variable is then
compared again with the expression (see ginStepRight() for an example
that fails), as _Bool forces the result to be 0/1. That happens in some
configurations of newer MSVC compilers. It's also problematic when
storing the result of such an expression in a narrower type.
Several gin macros have been declared in that style since gin's initial
commit in 8a3631f8d8.
There's a lot more macros like this, but this is the only one causing
regression test failures; and I don't want to commit and backpatch a
larger patch with lots of conflicts just before the next set of minor
releases.
Discussion: 20150811154237.GD17575@awork2.anarazel.de
Backpatch: All supported branches
We really need to sync all of our IANA-derived timezone code with upstream,
but that's going to be a large patch and I certainly don't care to shove
such a thing into stable branches immediately before a release. As a
stopgap, copy just the tzcode2016c logic that checks validity of timezone
abbreviations. This prevents getting multiple "time zone abbreviation
differs from POSIX standard" bleats with tzdata 2014b and later.
cost_subplan() supposed that the given subplan must have plan_rows > 0,
which as far as I can tell was true until recent refactoring of the
code in createplan.c; but now that code allows the Result for a provably
empty subquery to have plan_rows = 0. Rather than undo that change,
put in a clamp to prevent zero divide.
get_cheapest_fractional_path() likewise supposed that best_path->rows > 0.
This assumption has been wrong for longer. It's actually harmless given
IEEE float math, because a positive value divided by zero gives +Infinity
and compare_fractional_path_costs() will do the right thing with that.
Still, best not to assume that.
final_cost_nestloop() also seems to have some risks in this area, so
borrow the clamping logic already present in the mergejoin cost functions.
Lastly, remove unnecessary clamp_row_est() in planner.c's calls to
get_number_of_groups(). The only thing that function does with path_rows
is pass it to estimate_num_groups() which already has an internal clamp,
so we don't need the extra call; and if we did, the callers are arguably
the wrong place for it anyway.
First two items reported by Piotr Stefaniak, the others are products
of my nosing around for similar problems. No back-patch since there's
no evidence that problems arise in the back branches.
DST law changes in Azerbaijan, Chile, Haiti, Palestine, and Russia (Altai,
Astrakhan, Kirov, Sakhalin, Ulyanovsk regions). Historical corrections
for Lithuania, Moldova, Russia (Kaliningrad, Samara, Volgograd).
As of 2015b, the keepers of the IANA timezone database started to use
numeric time zone abbreviations (e.g., "+04") instead of inventing
abbreviations not found in the wild like "ASTT". This causes our rather
old copy of zic to whine "warning: time zone abbreviation differs from
POSIX standard" several times during "make install". This warning is
harmless according to the IANA folk, and I don't see any problems with
these abbreviations in some simple tests; but it seems like now would be
a good time to update our copy of the tzcode stuff. I'll look into that
soon.
We don't really want to encourage people to write numeric SQLSTATEs in
programs; that's unreadable and error-prone. Copy plpgsql's infrastructure
for converting between SQLSTATEs and exception names shown in Appendix A,
and modify examples in tests and documentation to do it that way.
Tcl has a convention for returning additional info about an error in a
global variable named errorCode. Up to now PL/Tcl has ignored that,
but this patch causes database errors caught by PL/Tcl to fill in
errorCode with useful information from the ErrorData struct.
Jim Nasby, reviewed by Pavel Stehule and myself
This avoids leaving dangling links in pg_operator; which while fairly
harmless are also unsightly.
While we're at it, simplify OperatorUpd, which went through
heap_modify_tuple for no very good reason considering it had already made
a tuple copy it could just scribble on.
Roma Sokolov, reviewed by Tomas Vondra, additional hacking by Robert Haas
and myself.
In commit 9118d03a8c we taught the planner to postpone evaluation of
set-returning functions in a SELECT's targetlist until after any sort done
to satisfy ORDER BY. However, if we postpone some SRFs this way while
others do not get postponed (because they're sort or group key columns)
we will break the traditional behavior by which all SRFs in the tlist run
in-step during ExecTargetList(), so that you get the least common multiple
of their periods not the product. Fix make_sort_input_target() so it will
not split up SRF evaluation in such cases.
There is still a hazard of similar odd behavior if there's a SRF in a
grouping column and another one that isn't, but that was true before
and we're just trying to preserve bug-compatibility with the traditional
behavior. This whole area is overdue to be rethought and reimplemented,
but we'll try to avoid changing behavior until then.
Per report from Regina Obe.
Some of the non-MSVC Windows buildfarm members seem to need this to avoid
getting "undefined symbol" errors on libpgfeutils' references to libpq.
I could understand that if libpq were a static library, but surely it is
not? Oh well, at least the extra reference is no more harmful than it is
for libpgcommon or libpgport.
This completes (at least for now) the project of getting rid of ad-hoc
linkages among the src/bin/ subdirectories. Everything they share is now
in src/fe_utils/ and is included from a static library at link time.
A side benefit is that we can restore the FLEX_NO_BACKUP check for
psqlscanslash.l. We might need to think of another way to do that check
if we ever need to build two lexers with that property in the same source
directory, but there's no foreseeable reason to need that.
Compilers that don't know that elog(ERROR) doesn't return complained
that this function might fail to return a value. Per buildfarm.
While at it, const-ify the function's declaration, since the intent
is evidently to always return a constant string.
Per discussion, we want to create a static library and put the stuff into
it that until now has been shared across src/bin/ directories by ad-hoc
methods like symlinking a source file. This commit creates the library and
populates it with a couple of files that contain the widely-useful portions
of pg_dump's dumputils.c file. dumputils.c survives, because it has some
stuff that didn't seem appropriate for fe_utils, but it's significantly
smaller and is no longer referenced from any other directory.
Follow-on patches will move more stuff into fe_utils.
The Mkvcbuild.pm hacking here is just a best guess; we'll see how the
buildfarm likes it.
This enables external code to create access methods. This is useful so
that extensions can add their own access methods which can be formally
tracked for dependencies, so that DROP operates correctly. Also, having
explicit support makes pg_dump work correctly.
Currently only index AMs are supported, but we expect different types to
be added in the future.
Authors: Alexander Korotkov, Petr Jelínek
Reviewed-By: Teodor Sigaev, Petr Jelínek, Jim Nasby
Commitfest-URL: https://commitfest.postgresql.org/9/353/
Discussion: https://www.postgresql.org/message-id/CAPpHfdsXwZmojm6Dx+TJnpYk27kT4o7Ri6X_4OSWcByu1Rm+VA@mail.gmail.com
Now that we have src/common/ for code shared between frontend and backend,
we can get rid of (most of) the klugy ways that the keyword table and
keyword lookup code were formerly shared between different uses.
This is a first step towards a more general plan of getting rid of
special-purpose kluges for sharing code in src/bin/.
I chose to merge kwlookup.c back into keywords.c, as it once was, and
always has been so far as keywords.h is concerned. We could have
kept them separate, but there is noplace that uses ScanKeywordLookup
without also wanting access to the backend's keyword list, so there
seems little point.
ecpg is still a bit weird, but at least now the trickiness is documented.
I think that the MSVC build script should require no adjustments beyond
what's done here ... but we'll soon find out.
Unfortunately, every version of glibc thus far tested has bugs whereby
strcoll() ordering does not match strxfrm() ordering as required by
the standard. This can result in, for example, corrupted indexes.
Disabling abbreviated keys in these cases slows down non-C-collation
string sorting considerably, but there seems to be no practical
alternative. Users who are confident that their libc implementations
are solid in this regard can re-enable the optimization by compiling
with TRUST_STRXFRM.
Users who have built indexes using PostgreSQL 9.5 or PostgreSQL 9.5.1
should REINDEX if there is a possibility that they may have been
affected by this problem.
Report by Marc-Olaf Jaschke. Investigation mostly by Tom Lane, with
help from Peter Geoghegan, Noah Misch, Stephen Frost, and me. Patch
by me, reviewed by Peter Geoghegan and Tom Lane.
Without this, contention on the freelist can become a pretty serious
problem on large servers.
Aleksander Alekseev, reviewed by Anastasia Lubennikova, Dilip Kumar,
and me.
User-facing (even tested by regression tests) error conditions were thrown
with elog(), hence had wrong SQLSTATE and were untranslatable. And the
error message texts weren't up to project style, either.
jsonb_set() could produce wrong answers or incorrect error reports, or in
the worst case even crash, when trying to convert a path-array element into
an integer for use as an array subscript. Per report from Vitaly Burovoy.
Back-patch to 9.5 where the faulty code was introduced (in commit
c6947010ce).
Michael Paquier
In commit afb9249d06, we (probably I) made ExecLockRows assign
null test tuples to all relations of the query while setting up to do an
EvalPlanQual recheck for a newly-updated locked row. This was sheerest
brain fade: we should only set test tuples for relations that are lockable
by the LockRows node, and in particular empty test tuples are only sensible
for inheritance child relations that weren't the source of the current
tuple from their inheritance tree. Setting a null test tuple for an
unrelated table causes it to return NULLs when it should not, as exhibited
in bug #14034 from Bronislav Houdek. To add insult to injury, doing it the
wrong way required two loops where one would suffice; so the corrected code
is even a bit shorter and faster.
Add a regression test case based on his example, and back-patch to 9.5
where the bug was introduced.
Instead of just "2" seconds, allow eg. "2.5" seconds. Per request
from Alvaro Herrera. No docs change since the docs didn't say you
couldn't do this already.
Include the \pset title string if there is one, and shorten the prefab
part of the header to be "timestamp (every Ns)". Per suggestion by
David Johnston.
Michael Paquier and Tom Lane
Parallel workers can now partially aggregate the data and pass the
transition values back to the leader, which can combine the partial
results to produce the final answer.
David Rowley, based on earlier work by Haribabu Kommi. Reviewed by
Álvaro Herrera, Tomas Vondra, Amit Kapila, James Sewell, and me.
Commit ac1d794 ("Make idle backends exit if the postmaster dies.")
introduced a regression on, at least, large linux systems. Constantly
adding the same postmaster_alive_fds to the OSs internal datastructures
for implementing poll/select can cause significant contention; leading
to a performance regression of nearly 3x in one example.
This can be avoided by using e.g. linux' epoll, which avoids having to
add/remove file descriptors to the wait datastructures at a high rate.
Unfortunately the current latch interface makes it hard to allocate any
persistent per-backend resources.
Replace, with a backward compatibility layer, WaitLatchOrSocket with a
new WaitEventSet API. Users can allocate such a Set across multiple
calls, and add more than one file-descriptor to wait on. The latter has
been added because there's upcoming postgres features where that will be
helpful.
In addition to the previously existing poll(2), select(2),
WaitForMultipleObjects() implementations also provide an epoll_wait(2)
based implementation to address the aforementioned performance
problem. Epoll is only available on linux, but that is the most likely
OS for machines large enough (four sockets) to reproduce the problem.
To actually address the aforementioned regression, create and use a
long-lived WaitEventSet for FE/BE communication. There are additional
places that would benefit from a long-lived set, but that's a task for
another day.
Thanks to Amit Kapila, who helped make the windows code I blindly wrote
actually work.
Reported-By: Dmitry Vasilyev Discussion:
CAB-SwXZh44_2ybvS5Z67p_CDz=XFn4hNAD=CnMEF+QqkXwFrGg@mail.gmail.com20160114143931.GG10941@awork2.anarazel.de
Previously latches for windows and unix had been implemented in
different files. A later patch introduce an expanded wait
infrastructure, keeping the implementation separate would introduce too
much duplication.
This basically just moves the functions, without too much change. The
reason to keep this separate is that it allows blame to continue working
a little less badly; and to make review a tiny bit easier.
Discussion: 20160114143931.GG10941@awork2.anarazel.de
After the previous fix in 6f1f34c9 msvc ended up looking for psqlscan.c
in the wrong directory.
David's fix just forces the path to be adjusted. That's not a
particularly pretty fix, but it hopefully will make the buildfarm green
again.
Author: David Rowley
Discussion: CAKJS1f_9CCi_t+LEgV5GWoCj3wjavcMoDc5qfcf_A0UwpQoPoA@mail.gmail.com
The point of this change is to use %pure-parser in pgbench's exprparse.y.
The immediate reason is that it turns out very ancient versions of bison
have a bug with the combination of a reentrant lexer and non-reentrant
parser. We could consider dropping support for such ancient bisons; but
considering that we might well need exprparse.y to be reentrant some day,
it seems better to make it so right now than to move the portability
goalposts. (AFAICT there's no particular performance consequence to this
change, either, so there's no good reason not to do it.)
Now, %pure-parser assumes that the called lexer is built with %option
bison-bridge. Because we're assuming bitwise compatibility of yyscan_t
(yyguts_t) data structures among all the psql/pgbench lexers, that
requirement propagates back to psql's lexers as well. But it's just a
few lines of change on that side too; and if psqlscan.l is to set the
baseline for a possibly-large family of lexers, it should err on the
side of including not omitting useful features.
pgbench now needs to use src/bin/psql/psqlscan.l, but it's not very clear
how to fit that into the MSVC build system. If this doesn't work I'm going
to need some help from somebody who actually understands those scripts ...
To allow multiline SQL commands in scripts, adopt the same rules psql uses
to decide what is the end of a SQL command, to wit, an unquoted semicolon
not encased in parentheses. Do this by importing the same flex lexer that
psql uses, since coping with stuff like dollar-quoted literals is hard to
get right without going the full nine yards.
This makes use of the infrastructure added in commit 0ea9efbe9e to
support independently-written flex lexers scanning the same PsqlScanState
input-buffer data structure. Since that infrastructure isn't very
friendly to ad-hoc parsing code such as strtok(), improve exprscan.l
so that it can parse either whitespace-separated words or expression
tokens, on demand, and rewrite pgbench.c's backslash-command parsing
code to always use the lexer to fetch tokens.
It's still the case that pgbench backslash commands extend to the end
of the line, no more and no less. That could be changed in a fairly
localized way now, and there was some interest in doing so, but it
seems like material for a separate patch.
In passing, make some marginal cleanups in syntax error reporting,
const-ify a few data structures that could use it, and run some of
this code through pgindent.
I can't tell whether the MSVC build scripts need to be taught explicitly
about the changes here or not, but the buildfarm will soon tell us.
Kyotaro Horiguchi and Tom Lane
Modern Perl has removed psed from its core distribution, so it might not
be readily available on some build platforms. We therefore replace its
use with a Perl script generated by s2p, which is equivalent to the sed
script. The latter is retained for non-MSVC builds to avoid creating a
new hard dependency on Perl for non-Windows tarball builds.
Backpatch to all live branches.
Michael Paquier and me.
This is a necessary preliminary step for making it play with psqlscan.l
given the way I set up the lexer input-buffer sharing mechanism in commit
0ea9efbe9e.
I've not tried to make it *actually* reentrant; there's still some static
variables laying about. But flex thinks it's reentrant, and that's what
counts.
In support of that, fix exprparse.y to pass through the yyscan_t from the
caller. Also do some minor code beautification, like not casting away
const.
Make some minor formatting adjustments to make it easier to diff these
files and see that they indeed implement the same flex rules (at least
to the extent that we want them to be the same).
(Someday it'd be nice to make ecpg's pgc.l more easily diff'able too,
but today is not that day.)
Also run relevant parts of these files and psqlscanslash.l through
pgindent.
No actual behavioral changes here, just obsessive neatnik-ism.
Now that we know about the %top{} trick, we can revert to building flex
lexers as separate .o files. This is worth doing for a couple of reasons
besides sheer cleanliness. We can narrow the scope of the -Wno-error flag
that's forced on scan.c. Also, since these grammar and lexer files are
so large, splitting them into separate build targets should have some
advantages in build speed, particularly in parallel or ccache'd builds.
We have quite a few other .l files that could be changed likewise, but the
above arguments don't apply to them, so the benefit of fixing them seems
pretty minimal. Leave the rest for some other day.
Previously, all scripts had the same probability of being chosen when
multiple of them were specified via -b, -f, -N, -S. With this commit,
-b and -f now search for an "@" in the script name and use the integer
found after it as the drawing probability for that script.
(One disadvantage is that if you have script whose names contain @, you
are now forced to specify "@1" at the end; otherwise the name's @ is
confused with a weight separator. We don't expect many pgbench script
with @ in their names in the wild, so this shouldn't be too serious a
problem.)
While at it, rework the interface between addScript, process_file,
process_builtin, and findBuiltin. It had gotten a bit out of hand with
recent commits.
Author: Fabien Coelho
Reviewed-By: Andres Freund, Robert Haas, Álvaro Herrera, Michaël Paquier
Discussion: http://www.postgresql.org/message-id/alpine.DEB.2.10.1603160721240.1666@sto
Buildfarm results show that the ability to attach pg_attribute_printf
decoration to a function pointer appeared somewhere between gcc 2.95.3
and gcc 4.0.1. Guess that it was there in 4.0.
We used to require the server key file to have permissions 0600 or less
for best security. But some systems (such as Debian) have certificate
and key files managed by the operating system that can be shared with
other services. In those cases, the "postgres" user is made a member of
a special group that has access to those files, and the server key file
has permissions 0640. To accommodate that kind of setup, also allow the
key file to have permissions 0640 but only if owned by root.
From: Christoph Berg <myon@debian.org>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
The existing infrastructure for FLEX_NO_BACKUP doesn't work reliably
when two lexers are built in parallel in the same directory. We can
probably fix that, but as a short-term workaround, just don't make
the check for psqlscanslash.l.
Per buildfarm.
This gets us to a point where psqlscan.l can be used by other frontend
programs for the same purpose psql uses it for, ie to detect when it's
collected a complete SQL command from input that is divided across
line boundaries. Moreover, other programs can supply their own lexers
for backslash commands of their own choosing. A follow-on patch will
use this in pgbench.
The end result here is roughly the same as in Kyotaro Horiguchi's
0001-Make-SQL-parser-part-of-psqlscan-independent-from-ps.patch, although
the details of the method for switching between lexers are quite different.
Basically, in this patch we share the entire PsqlScanState, YY_BUFFER_STATE
stack, *and* yyscan_t between different lexers. The only thing we need
to do to switch to a different lexer is to make sure the start_state is
valid for the new lexer. This works because flex doesn't keep any other
persistent state that depends on the specific lexing tables generated for
a particular .l file. (We are assuming that both lexers are built with
the same flex version, or at least versions that are compatible with
respect to the contents of yyscan_t; but that doesn't seem likely to
be a big problem in practice, considering how slowly flex changes.)
Aside from being more efficient than Horiguchi-san's original solution,
this avoids possible corner-case changes in semantics: the original code
was capable of popping the input buffer stack while still staying in
backslash-related parsing states. I'm not sure that that equates to any
useful user-visible behaviors, but I'm not sure it doesn't either, so
I'm loath to assume that we only need to consider the topmost buffer when
parsing a backslash command.
I've attempted to update the MSVC build scripts for the added .l file,
but will rely on the buildfarm to see if I missed anything.
Kyotaro Horiguchi and Tom Lane
Change psqlscan.l to specify '%option reentrant', adjust internal APIs
to match, and get rid of its internal static variables. While this is
good cleanup in an abstract sense, the reason to do it right now is that
it seems the only practical way to support use of separate flex lexers
with common PsqlScanState infrastructure. If we build two non-reentrant
lexers then we are going to have problems with dangling buffer pointers
in whichever lexer isn't active when we transition from one buffer to
another, as well as curious side-effects if we try to share any code
between the files. (Horiguchi-san had a different solution to that in his
pending patch, but I find it ugly and probably broken for corner cases.)
Depending on which version of flex you're using, this may result in getting
a "warning: unused variable 'yyg'" warning from psqlscan, similar to the
one you'd have seen for a long time in backend/parser/scan.l. I put a
local -Wno-error into CFLAGS for the file, for the convenience of those
who compile with -Werror.
Also, stop compiling psqlscan as part of mainloop.c, and make it a
standalone build target instead. This is a lot cleaner than before, though
it doesn't really change much in practice as of this commit. (I'm not sure
whether the MSVC build scripts will need some help with this part, but the
buildfarm will soon tell us.)
The distinction between "archive" and "hot_standby" existed only because
at the time "hot_standby" was added, there was some uncertainty about
stability. This is now a long time ago. We would like to move forward
with simplifying the replication configuration, but this distinction is
in the way, because a primary server cannot tell (without asking a
standby or predicting the future) which one of these would be the
appropriate level.
Pick a new name for the combined setting to make it clearer that it
covers all (non-logical) backup and replication uses. The old values
are still accepted but are converted internally.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: David Steele <david@pgmasters.net>
Remove assorted external references from psqlscan.l in preparation for
making it usable by other frontend programs. This mostly involves
getting rid of direct calls to psql_error() and GetVariable() in favor
of introducing a callback-functions struct to encapsulate variable
fetching and error printing. In addition, pass the current encoding
and standard-strings status as additional parameters to psql_scan_setup
instead of looking directly at "pset" or calling additional functions.
I did not bother to change some references to psql_error that are in
functions that will soon migrate to a psql-specific backslash-command
lexer. Other than that, this version of psqlscan.l is capable of
compiling standalone. It still depends on assorted src/common functions
as well as some encoding-related libpq functions, but we expect that
all programs using it will be happy with those dependencies.
Kyotaro Horiguchi, somewhat editorialized on by me
Tom Lane
Kevin Grittner
Alvaro Herrera
Andres Freund
Stephen Frost
Teodor Sigaev
Magnus Hagander
Peter Eisentraut
Robert Haas
Andrew Dunstan
Fujii Masao
Simon Riggs
Noah Misch
Dean Rasheed