There's no reason not to expose both restart_lsn and confirmed_flush
since they have rather distinct meanings. The former is the oldest WAL
still required and valid for both physical and logical slots, whereas
the latter is the location up to which a logical slot's consumer has
confirmed receiving data. Most of the time a slot will require older
WAL (i.e. restart_lsn) than the confirmed
position (i.e. confirmed_flush_lsn).

Author: Marko Tiikkaja, editorialized by me
Discussion: 559D110B.1020109@joh.to

Oversight in commit cb3384a0.
Back-patch to 9.1, like that commit.

It's against project policy to use elog() for user-facing errors, or to
omit an errcode() selection for errors that aren't supposed to be "can't
happen" cases.  Fix all the violations of this policy that result in
ERRCODE_INTERNAL_ERROR log entries during the standard regression tests,
as errors that can reliably be triggered from SQL surely should be
considered user-facing.

I also looked through all the files touched by this commit and fixed
other nearby problems of the same ilk.  I do not claim to have fixed
all violations of the policy, just the ones in these files.

In a few places I also changed existing ERRCODE choices that didn't
seem particularly appropriate; mainly replacing ERRCODE_SYNTAX_ERROR
by something more specific.

Back-patch to 9.5, but no further; changing ERRCODE assignments in
stable branches doesn't seem like a good idea.

An EAN beginning with 979 (but not 9790 - those are ISMN's) are accepted
as ISBN numbers, but they cannot be represented in the old, 10-digit ISBN
format. They must be output in the new 13-digit ISBN-13 format. We printed
out an incorrect value for those.

Also add a regression test, to test this and some other basic functionality
of the module.

Patch by Fabien Coelho. This fixes bug #13442, reported by B.Z. Backpatch
to 9.1, where we started to recognize ISBN-13 numbers.

Buildfarm member hornet, at least, seems to want -lm in the link command.
Probably this is due to the just-added use of isnan().

The original implementation of TABLESAMPLE modeled the tablesample method
API on index access methods, which wasn't a good choice because, without
specialized DDL commands, there's no way to build an extension that can
implement a TSM.  (Raw inserts into system catalogs are not an acceptable
thing to do, because we can't undo them during DROP EXTENSION, nor will
pg_upgrade behave sanely.)  Instead adopt an API more like procedural
language handlers or foreign data wrappers, wherein the only SQL-level
support object needed is a single handler function identified by having
a special return type.  This lets us get rid of the supporting catalog
altogether, so that no custom DDL support is needed for the feature.

Adjust the API so that it can support non-constant tablesample arguments
(the original coding assumed we could evaluate the argument expressions at
ExecInitSampleScan time, which is undesirable even if it weren't outright
unsafe), and discourage sampling methods from looking at invisible tuples.
Make sure that the BERNOULLI and SYSTEM methods are genuinely repeatable
within and across queries, as required by the SQL standard, and deal more
honestly with methods that can't support that requirement.

Make a full code-review pass over the tablesample additions, and fix
assorted bugs, omissions, infelicities, and cosmetic issues (such as
failure to put the added code stanzas in a consistent ordering).
Improve EXPLAIN's output of tablesample plans, too.

Back-patch to 9.5 so that we don't have to support the original API
in production.

Uriy Zhuravlev and Alexander Korotkov, reviewed by Jeff Janes, some cleanup
by me.

to make it faster to implement indexed queries where some keys are
common and some are rare.

Patch by Jeff Janes

This still doesn't work correctly with Python 3, but I am committing
this so we can get Cygwin buildfarm members building with Python 2.

The result closely resembles linking of these modules for the "win32"
port.  Augment the $(exports_file) header so the file is also usable as
an import file.  Unfortunately, relocating an AIX installation will now
require adding $(pkglibdir) to LD_LIBRARY_PATH.  Back-patch to 9.5,
where the modules were introduced.

The MSVC build system already did this, and building against Python 3
requires it.  Back-patch to 9.5, where the module was introduced.

Also this patch removes obsolete comment.

Back-patch to 9.5 where BRIN index was added.

The AIX 7.1 libm is static, and AIX postgres executables do not export
symbols acquired from libraries.  Back-patch to 9.5, where commit
cfe12763 added a sqrt() call.

This allows convenient checking for existence of a GUC from SQL, which is
particularly useful when dealing with custom variables.

David Christensen, reviewed by Jeevan Chalke

Patch by David Rowley. Backpatch to 9.5, as some of the calls were new in
9.5, and keeping the code in sync with master makes future backpatching
easier.

Commit 179cdd09 added macros to check if a filename is a WAL segment
or other such file. However there were still some instances of the
strlen + strspn combination to check for that in WAL-related utilities
like pg_archivecleanup. Those checks can be replaced with the macros.

This patch makes use of the macros in those utilities and
which would make the code a bit easier to read.

Back-patch to 9.5.

Michael Paquier

test_decoding used fastgetattr() to extract column values. That's wrong
when decoding updates and deletes if a table's replica identity is set
to FULL and new columns have been added since the old version of the
tuple was created. Due to the lack of a crosscheck with the datum's
natts values an invalid value will be output, leading to errors or
worse.

Bug: #13470
Reported-By: Krzysztof Kotlarski
Discussion: 20150626100333.3874.90852@wrigleys.postgresql.org

Backpatch to 9.4, where the feature, including the bug, was added.

Newer Python versions randomize the hash seed for dictionaries,
resulting in a random output order, which messes up the regression test
diffs.

Instead, use Python assert to compare the dictionaries with their
expected value.

This removes pg_audit, per discussion:

20150528082038.GU26667@tamriel.snowman.net

Fix some places where pgindent did silly stuff, often because project
style wasn't followed to begin with.  (I've not touched the atomics
headers, though.)

Remove a bunch of "extern Datum foo(PG_FUNCTION_ARGS);" declarations that
are no longer needed now that PG_FUNCTION_INFO_V1(foo) provides that.

Some of these were evidently missed in commit e7128e8d, but others
were cargo-culted in in code added since then.  Possibly that can be blamed
in part on the fact that we'd not fixed relevant documentation examples,
which I've now done.

Use "a" and "an" correctly, mostly in comments. Two error messages were
also fixed (they were just elogs, so no translation work required). Two
function comments in pg_proc.h were also fixed. Etsuro Fujita reported one
of these, but I found a lot more with grep.

Also fix a few other typos spotted while grepping for the a/an typos.
For example, "consists out of ..." -> "consists of ...". Plus a "though"/
"through" mixup reported by Euler Taveira.

Many of these typos were in old code, which would be nice to backpatch to
make future backpatching easier. But much of the code was new, and I didn't
feel like crafting separate patches for each branch. So no backpatching.

Defer lookup of opfamily and input type of a of a user specified opclass
until the optimizer selects among available unique indexes; and store
the opclass in the parse analyzed tree instead.  The primary reason for
doing this is that for rule deparsing it's easier to use the opclass
than the previous representation.

While at it also rename a variable in the inference code to better fit
it's purpose.

This is separate from the actual fixes for deparsing to make review
easier.

The plain C string language name needs to be wrapped in makeString() so
that the parse tree is copyable.  This is detectable by
-DCOPY_PARSE_PLAN_TREES.  Add a test case for the COMMENT case.

Also make the quoting in the error messages more consistent.

discovered by Tom Lane

This has been the predominant outcome.  When the output of decrypting
with a wrong key coincidentally resembled an OpenPGP packet header,
pgcrypto could instead report "Corrupt data", "Not text data" or
"Unsupported compression algorithm".  The distinct "Corrupt data"
message added no value.  The latter two error messages misled when the
decrypted payload also exhibited fundamental integrity problems.  Worse,
error message variance in other systems has enabled cryptologic attacks;
see RFC 4880 section "14. Security Considerations".  Whether these
pgcrypto behaviors are likewise exploitable is unknown.

In passing, document that pgcrypto does not resist side-channel attacks.
Back-patch to 9.0 (all supported versions).

Security: CVE-2015-3167

The previous coding in hstore_plpython and ltree_plpython wiped out any
values set by the base makefiles.  This at least had the effect of running
the tests in "regression" not "contrib_regression" as expected.  These
being pretty new modules, there might be other bad effects we'd not
noticed yet.

Clean up the Makefile, per Michael Paquier.

Classify REINDEX as we do in core, use '1.0' for the version, per Fujii.

Dmitriy Olshevskiy

This SQL standard functionality allows to aggregate data by different
GROUP BY clauses at once. Each grouping set returns rows with columns
grouped by in other sets set to NULL.

This could previously be achieved by doing each grouping as a separate
query, conjoined by UNION ALLs. Besides being considerably more concise,
grouping sets will in many cases be faster, requiring only one scan over
the underlying data.

The current implementation of grouping sets only supports using sorting
for input. Individual sets that share a sort order are computed in one
pass. If there are sets that don't share a sort order, additional sort &
aggregation steps are performed. These additional passes are sourced by
the previous sort step; thus avoiding repeated scans of the source data.

The code is structured in a way that adding support for purely using
hash aggregation or a mix of hashing and sorting is possible. Sorting
was chosen to be supported first, as it is the most generic method of
implementation.

Instead of, as in an earlier versions of the patch, representing the
chain of sort and aggregation steps as full blown planner and executor
nodes, all but the first sort are performed inside the aggregation node
itself. This avoids the need to do some unusual gymnastics to handle
having to return aggregated and non-aggregated tuples from underlying
nodes, as well as having to shut down underlying nodes early to limit
memory usage.  The optimizer still builds Sort/Agg node to describe each
phase, but they're not part of the plan tree, but instead additional
data for the aggregation node. They're a convenient and preexisting way
to describe aggregation and sorting.  The first (and possibly only) sort
step is still performed as a separate execution step. That retains
similarity with existing group by plans, makes rescans fairly simple,
avoids very deep plans (leading to slow explains) and easily allows to
avoid the sorting step if the underlying data is sorted by other means.

A somewhat ugly side of this patch is having to deal with a grammar
ambiguity between the new CUBE keyword and the cube extension/functions
named cube (and rollup). To avoid breaking existing deployments of the
cube extension it has not been renamed, neither has cube been made a
reserved keyword. Instead precedence hacking is used to make GROUP BY
cube(..) refer to the CUBE grouping sets feature, and not the function
cube(). To actually group by a function cube(), unlikely as that might
be, the function name has to be quoted.

Needs a catversion bump because stored rules may change.

Author: Andrew Gierth and Atri Sharma, with contributions from Andres Freund
Reviewed-By: Andres Freund, Noah Misch, Tom Lane, Svenne Krap, Tomas
    Vondra, Erik Rijkers, Marti Raudsepp, Pavel Stehule
Discussion: CAOeZVidmVRe2jU6aMk_5qkxnB7dfmPROzM7Ur8JPW5j8Y5X-Lw@mail.gmail.com

For upcoming BRIN opclasses, it's convenient to have strategy numbers
defined in a single place.  Since there's nothing appropriate, create
it.  The StrategyNumber typedef now lives there, as well as existing
strategy numbers for B-trees (from skey.h) and R-tree-and-friends (from
gist.h).  skey.h is forced to include stratnum.h because of the
StrategyNumber typedef, but gist.h is not; extensions that currently
rely on gist.h for rtree strategy numbers might need to add a new

A few .c files can stop including skey.h and/or gist.h, which is a nice
side benefit.

Per discussion:
https://www.postgresql.org/message-id/20150514232132.GZ2523@alvh.no-ip.org

Authored by Emre Hasegeli and Álvaro.

(It's not clear to me why bootscanner.l has any #include lines at all.)

Add a TABLESAMPLE clause to SELECT statements that allows
user to specify random BERNOULLI sampling or block level
SYSTEM sampling. Implementation allows for extensible
sampling functions to be written, using a standard API.
Basic version follows SQLStandard exactly. Usable
concrete use cases for the sampling API follow in later
commits.

Petr Jelinek

Reviewed by Michael Paquier and Simon Riggs

No need to have pg_audit.conf any longer since the regression tests are
just loading the module at the start of each session (to simulate being
in shared_preload_libraries, which isn't something we can actually make
happen on the buildfarm itself, it seems).

Pointed out by Tom

Refactoring ahead of tablesample patch

Requested and reviewed by Michael Paquier

Petr Jelinek