Extend xfunc.sgml's discussion of set-returning functions to show an
example of using LATERAL, and recommend that over putting SRFs in the
targetlist.
In passing, reword func.sgml's section on set-returning functions so
that it doesn't claim that the functions listed therein are all the
built-in set-returning functions. That hasn't been true for a long
time, and trying to make it so doesn't seem like it would be an
improvement. (Perhaps we should rename that section?)
Both per suggestions from Merlin Moncure.
Only warn when connecting to a newer server, since connecting to older
servers works pretty well nowadays. Also update the documentation a
little about current psql/server compatibility expectations.
The existing documentation in Linux Memory Overcommit seemed to
assume that PostgreSQL itself could never be the problem, or at
least it didn't tell you what to do about it.
Per discussion with Craig Ringer and Kevin Grittner.
This is so that these sections will have stable HTML tags that one can
link to, rather than things like "AEN1902". Perhaps we should mount a
campaign to do this everywhere, but I've found myself pointing at
syntax.sgml subsections often enough to be sure it's useful here.
As of 9.2, constraint exclusion should work okay with prepared statements:
the planner will try custom plans with actual values of the parameters,
and observe that they are a lot cheaper than the generic plan, and thus
never fall back to using the generic plan. Noted by Tatsuhito Kasahara.
The docs claimed that this mode only waits for the standby to receive WAL
data, but actually it waits for the data to be written out to the standby's
OS; which is a pretty significant difference because it removes the risk of
crash of the walreceiver process.
libxslt offers the ability to read and write both files and URLs through
stylesheet commands, thus allowing unprivileged database users to both read
and write data with the privileges of the database server. Disable that
through proper use of libxslt's security options.
Also, remove xslt_process()'s ability to fetch documents and stylesheets
from external files/URLs. While this was a documented "feature", it was
long regarded as a terrible idea. The fix for CVE-2012-3489 broke that
capability, and rather than expend effort on trying to fix it, we're just
going to summarily remove it.
While the ability to write as well as read makes this security hole
considerably worse than CVE-2012-3489, the problem is mitigated by the fact
that xslt_process() is not available unless contrib/xml2 is installed,
and the longstanding warnings about security risks from that should have
discouraged prudent DBAs from installing it in security-exposed databases.
Reported and fixed by Peter Eisentraut.
Security: CVE-2012-3488
Replace unix_socket_directory with unix_socket_directories, which is a list
of socket directories, and adjust postmaster's code to allow zero or more
Unix-domain sockets to be created.
This is mostly a straightforward change, but since the Unix sockets ought
to be created after the TCP/IP sockets for safety reasons (better chance
of detecting a port number conflict), AddToDataDirLockFile needs to be
fixed to support out-of-order updates of data directory lockfile lines.
That's a change that had been foreseen to be necessary someday anyway.
Honza Horak, reviewed and revised by Tom Lane
Should be limited to the maximum number of connections excluding
autovacuum workers, not including.
Add similar check for max_wal_senders, which should never be higher than
max_connections.
Previously, the -1 option was silently ignored.
Also, emit an error if -1 is used in a context where it won't be
respected, to avoid user confusion.
Original patch by Fabien COELHO, but this version is quite different
from the original submission.
This patch implements the standard syntax of LATERAL attached to a
sub-SELECT in FROM, and also allows LATERAL attached to a function in FROM,
since set-returning function calls are expected to be one of the principal
use-cases.
The main change here is a rewrite of the mechanism for keeping track of
which relations are visible for column references while the FROM clause is
being scanned. The parser "namespace" lists are no longer lists of bare
RTEs, but are lists of ParseNamespaceItem structs, which carry an RTE
pointer as well as some visibility-controlling flags. Aside from
supporting LATERAL correctly, this lets us get rid of the ancient hacks
that required rechecking subqueries and JOIN/ON and function-in-FROM
expressions for invalid references after they were initially parsed.
Invalid column references are now always correctly detected on sight.
In passing, remove assorted parser error checks that are now dead code by
virtue of our having gotten rid of add_missing_from, as well as some
comments that are obsolete for the same reason. (It was mainly
add_missing_from that caused so much fudging here in the first place.)
The planner support for this feature is very minimal, and will be improved
in future patches. It works well enough for testing purposes, though.
catversion bump forced due to new field in RangeTblEntry.
century specifications just like positive/AD centuries. Previously the
behavior was either wrong or inconsistent with positive/AD handling.
Centuries without years now always assume the first year of the century,
which is now documented.
After taking awhile to digest the row-processor feature that was added to
libpq in commit 92785dac2e, we've concluded
it is over-complicated and too hard to use. Leave the core infrastructure
changes in place (that is, there's still a row processor function inside
libpq), but remove the exposed API pieces, and instead provide a "single
row" mode switch that causes PQgetResult to return one row at a time in
separate PGresult objects.
This approach incurs more overhead than proper use of a row processor
callback would, since construction of a PGresult per row adds extra cycles.
However, it is far easier to use and harder to break. The single-row mode
still affords applications the primary benefit that the row processor API
was meant to provide, namely not having to accumulate large result sets in
memory before processing them. Preliminary testing suggests that we can
probably buy back most of the extra cycles by micro-optimizing construction
of the extra results, but that task will be left for another day.
Marko Kreen
The most user-visible part of this is to change the long options
--statusint and --noloop to --status-interval and --no-loop,
respectively, per discussion.
Also, consistently enclose file names in double quotes, per our
conventions; and consistently use the term "transaction log file" to
talk about WAL segments. (Someday we may need to go over this
terminology and make it consistent across the whole source code.)
Finally, reflow the code to better fit in 80 columns, and have pgindent
fix it up some more.
The initially implemented syntax, "CHECK NO INHERIT (expr)" was not
deemed very good, so switch to "CHECK (expr) NO INHERIT" instead. This
way it looks similar to SQL-standards compliant constraint attribute.
Backport to 9.2 where the new syntax and feature was introduced.
Per discussion.
This is apparently faster than doing things the other way around when
the scale factor is large.
Along the way, adjust -n to suppress vacuuming during initialization
as well as during test runs.
Jeff Janes, with some small changes by me.
Commit 3855968f32 added syntax, pg_dump,
psql support, and documentation, but the triggers didn't actually fire.
With this commit, they now do. This is still a pretty basic facility
overall because event triggers do not get a whole lot of information
about what the user is trying to do unless you write them in C; and
there's still no option to fire them anywhere except at the very
beginning of the execution sequence, but it's better than nothing,
and a good building block for future work.
Along the way, add a regression test for ALTER LARGE OBJECT, since
testing of event triggers reveals that we haven't got one.
Dimitri Fontaine and Robert Haas
They don't actually do anything yet; that will get fixed in a
follow-on commit. But this gets the basic infrastructure in place,
including CREATE/ALTER/DROP EVENT TRIGGER; support for COMMENT,
SECURITY LABEL, and ALTER EXTENSION .. ADD/DROP EVENT TRIGGER;
pg_dump and psql support; and documentation for the anticipated
initial feature set.
Dimitri Fontaine, with review and a bunch of additional hacking by me.
Thom Brown extensively reviewed earlier versions of this patch set,
but there's not a whole lot of that code left in this commit, as it
turns out.
Historically we have not worried about fsync'ing anything during initdb
(in fact, initdb intentionally passes -F to each backend launch to prevent
it from fsync'ing). But with filesystems getting more aggressive about
caching data, that's not such a good plan anymore. Make initdb do a pass
over the finished data directory tree to fsync everything. For testing
purposes, the -N/--nosync flag can be used to restore the old behavior.
Also, testing shows that on Linux, sync_file_range() is much faster than
posix_fadvise() for hinting to the kernel that an fsync is coming,
apparently because the latter blocks on a rather small request queue while
the former doesn't. So use this function if available in initdb, and also
in the backend's pg_flush_data() (where it currently will affect only the
speed of CREATE DATABASE's cloning step).
We will later make pg_regress invoke initdb with the --nosync flag
to avoid slowing down cases such as "make check" in contrib. But
let's not do so until we've shaken out any portability issues in this
patch.
Jeff Davis, reviewed by Andres Freund
These functions support removing or replacing array element value(s)
matching a given search value. Although intended mainly to support a
future array-foreign-key feature, they seem useful in their own right.
Marco Nenciarini and Gabriele Bartolini, reviewed by Alex Hunsaker
This hasn't been true since 9.1, when the default was changed to -1.
Remove the reference completely, keeping the discussion of the parameter
and it's shared memory effects on the config page.
Instead of letting every backend participating in a group commit wait
independently, have the first one that becomes ready to flush WAL wait
for the configured delay, and let all the others wait just long enough
for that first process to complete its flush. This greatly increases
the chances of being able to configure a commit_delay setting that
actually improves performance.
As a side consequence of this change, commit_delay now affects all WAL
flushes, rather than just commits. There was some discussion on
pgsql-hackers about whether to rename the GUC to, say, wal_flush_delay,
but in the absence of consensus I am leaving it alone for now.
Peter Geoghegan, with some changes, mostly to the documentation, by me.
A similar change was made previously for pg_cancel_backend, so now it
all matches again.
Dan Farina, reviewed by Fujii Masao, Noah Misch, and Jeff Davis,
with slight kibitzing on the doc changes by me.
The xlogid + segno representation of a particular WAL segment doesn't make
much sense in pg_resetxlog anymore, now that we don't use that anywhere
else. Use the WAL filename instead, since that's a convenient way to name a
particular WAL segment.
I did this partially for pg_resetxlog in the original xlogid/segno -> uint64
patch, but I neglected pg_upgrade and the docs. This should now be more
complete.
The latter was already the dominant use, and it's preferable because
in C the convention is that intXX means XX bits. Therefore, allowing
mixed use of int2, int4, int8, int16, int32 is obviously confusing.
Remove the typedefs for int2 and int4 for now. They don't seem to be
widely used outside of the PostgreSQL source tree, and the few uses
can probably be cleaned up by the time this ships.
Also, add some cross-links to the indexing documentation, so it's easier
to notice that && and other array operators have index support.
Ryan Kelly, edited by me.
The option --foreign-keys, used at initialization time, will create foreign
key constraints for the columns that represent references to other tables'
primary keys. This can help in benchmarking FK performance.
Jeff Janes
Previously, when executing an ON UPDATE SET NULL or SET DEFAULT action for
a multicolumn MATCH SIMPLE foreign key constraint, we would set only those
referencing columns corresponding to referenced columns that were changed.
This is what the SQL92 standard said to do --- but more recent versions
of the standard say that all referencing columns should be set to null or
their default values, no matter exactly which referenced columns changed.
At least for SET DEFAULT, that is clearly saner behavior. It's somewhat
debatable whether it's an improvement for SET NULL, but it appears that
other RDBMS systems read the spec this way. So let's do it like that.
This is a release-notable behavioral change, although considering that
our documentation already implied it was done this way, the lack of
complaints suggests few people use such cases.
Previously we followed the SQL92 wording, "MATCH <unspecified>", but since
SQL99 there's been a less awkward way to refer to the default style.
In addition to the code changes, pg_constraint.confmatchtype now stores
this match style as 's' (SIMPLE) rather than 'u' (UNSPECIFIED). This
doesn't affect pg_dump or psql because they use pg_get_constraintdef()
to reconstruct foreign key definitions. But other client-side code might
examine that column directly, so this change will have to be marked as
an incompatibility in the 9.3 release notes.
Before, some places didn't document the short options (-? and -V),
some documented both, some documented nothing, and they were listed in
various orders. Now this is hopefully more consistent and complete.
Since this is the easy way of doing it, it should be listed first. All
the old information is retained for those who want the more advanced way.
Also adds a subheading for compressing logs, that seems to have been missing
Aside from adjusting the documentation to say that these are deprecated,
we now report a warning (not an error) for use of GLOBAL, since it seems
fairly likely that we might change that to request SQL-spec-compliant temp
table behavior in the foreseeable future. Although our handling of LOCAL
is equally nonstandard, there is no evident interest in ever implementing
SQL modules, and furthermore some other products interpret LOCAL as
behaving the same way we do. So no expectation of change and no warning
for LOCAL; but it still seems a good idea to deprecate writing it.
Noah Misch
The simplest way to handle this is just to copy-and-paste the relevant
code block in fork_process.c, so that's what I did. (It's possible that
something more complicated would be useful to packagers who want to work
with either the old or the new API; but at this point the number of such
people is rapidly approaching zero, so let's just get the minimal thing
done.) Update relevant documentation as well.
Remove a couple of items that were actually back-patched bug fixes.
Add additional details to a couple of items which lacked a description.
Improve attributions for a couple of items I was involved with.
A few other miscellaneous corrections.
getopt_long() allows abbreviating long options, so we might as well
give the option the full name, and users can abbreviate it how they
like.
Do some general polishing of the --help output at the same time.
To replace it, add -X/--xlog-method that allows the specification
of fetch or stream.
Do this to avoid unnecessary backwards-incompatiblity. Spotted and
suggested by Peter Eisentraut.
Since the replication protocol deals with TimestampTz, we need to
care for the floating point case as well in the frontend tools.
Fujii Masao, with changes from Magnus Hagander
The initial implementation of pg_dump's --section option supposed that the
existing --schema-only and --data-only options could be made equivalent to
--section settings. This is wrong, though, due to dubious but long since
set-in-stone decisions about where to dump SEQUENCE SET items, as seen in
bug report from Martin Pitt. (And I'm not totally convinced there weren't
other bugs, either.) Undo that coupling and instead drive --section
filtering off current-section state tracked as we scan through the TOC
list to call _tocEntryRequired().
To make sure those decisions don't shift around and hopefully save a few
cycles, run _tocEntryRequired() only once per TOC entry and save the result
in a new TOC field. This required minor rejiggering of ACL handling but
also allows a far cleaner implementation of inhibit_data_for_failed_table.
Also, to ensure that pg_dump and pg_restore have the same behavior with
respect to the --section switches, add _tocEntryRequired() filtering to
WriteToc() and WriteDataChunks(), rather than trying to implement section
filtering in an entirely orthogonal way in dumpDumpableObject(). This
required adjusting the handling of the special ENCODING and STDSTRINGS
items, but they were pretty weird before anyway.
Minor other code review for the patch, too.
Drop special handling of host component with slashes to mean
Unix-domain socket. Specify it as separate parameter or using
percent-encoding now.
Allow omitting username, password, and port even if the corresponding
designators are present in URI.
Handle percent-encoding in query parameter keywords.
Alex Shulgin
some documentation improvements by myself
Per discussion, we should explain that we follow RFC 3339 and not really
the letter of the ISO 8601 spec for timestamp output format. Mostly
Brendan Jurd's wording, though I tweaked it to clarify that we do take 'T'
on input. Minor additional copy-editing and markup-tweaking, too.
Robert Haas
Tom Lane
Peter Eisentraut
Bruce Momjian
Heikki Linnakangas
Magnus Hagander
Simon Riggs
Alvaro Herrera