In patch 82233ce7, AbortStartTime wasn't being reset appropriately
after the restart sequence, causing subsequent iterations through
ServerLoop to malfunction.

Robins Tharakan, reviewed by Szymon Guz

Robins Tharakan, reviewed by Szymon Guz

Specifically, permit attaching them to the error in RAISE and retrieving
them from a caught error in GET STACKED DIAGNOSTICS.  RAISE enforces
nothing about the content of the fields; for its purposes, they are just
additional string fields.  Consequently, clarify in the protocol and
libpq documentation that the usual relationships between error fields,
like a schema name appearing wherever a table name appears, are not
universal.  This freedom has other applications; consider a FDW
propagating an error from an RDBMS having no schema support.

Back-patch to 9.3, where core support for the error fields was
introduced.  This prevents the confusion of having a release where libpq
exposes the fields and PL/pgSQL does not.

Pavel Stehule, lexical revisions by Noah Misch.

The web site is dead, and the Wayback Machine shows that it didn't have
much useful content before.

This mirrors the equivalent error cases in pg_dump.

To that end, support tags rather than lengths for external datums.
As an example of how this can be used, add support or "indirect"
tuples which point to some externally allocated memory containing
a toast tuple.  Similar infrastructure could be used for other
purposes, including, perhaps, support for alternative compression
algorithms.

Andres Freund, reviewed by Hitoshi Harada and myself

Make it easier for readers of the FP docs to find out about possibly
truncated values.

Per complaint from Tom Duffey in message
F0E0F874-C86F-48D1-AA2A-0C5365BF5118@trillitech.com

Author: Albe Laurenz
Reviewed by: Abhijit Menon-Sen

With -Wtype-limits, gcc correctly points out that size_t can never be < 0.
Backpatch to 9.3 and 9.2. It's been like this forever, but in <= 9.1 you got
a lot other warnings with -Wtype-limits anyway (at least with my version of
gcc).

Andres Freund

On the command line, GUC option strings are handled by the guc parser,
not by the shell parser, so '' is the proper way to represent a
zero-length string.  This reverts commit
3132a9b7.

SnapshotNow scans have the undesirable property that, in the face of
concurrent updates, the scan can fail to see either the old or the new
versions of the row.  In many cases, we work around this by requiring
DDL operations to hold AccessExclusiveLock on the object being
modified; in some cases, the existing locking is inadequate and random
failures occur as a result.  This commit doesn't change anything
related to locking, but will hopefully pave the way to allowing lock
strength reductions in the future.

The major issue has held us back from making this change in the past
is that taking an MVCC snapshot is significantly more expensive than
using a static special snapshot such as SnapshotNow.  However, testing
of various worst-case scenarios reveals that this problem is not
severe except under fairly extreme workloads.  To mitigate those
problems, we avoid retaking the MVCC snapshot for each new scan;
instead, we take a new snapshot only when invalidation messages have
been processed.  The catcache machinery already requires that
invalidation messages be sent before releasing the related heavyweight
lock; else other backends might rely on locally-cached data rather
than scanning the catalog at all.  Thus, making snapshot reuse
dependent on the same guarantees shouldn't break anything that wasn't
already subtly broken.

Patch by me.  Review by Michael Paquier and Andres Freund.

The dependencies on the spi and dummy_seclabel contrib modules were
incomplete, because they did not pick up automatically generated
dependencies on header files.  This will manifest itself especially when
switching major versions, where the contrib modules would not be
recompiled to contain the new version number, leading to regression test
failures.

To fix this, use the submake approach already in use elsewhere, so that
the contrib modules are built using their full rules.

On Unix, you can embed double-quotes in single-quotes, and via versa.
However, on Windows, you can only escape double-quotes in double-quotes,
so use that in the pg_dump -t/table example.
Backpatch to 9.3.
Report from Mike Toews

David Fetter and Andrew Gierth, reviewed by Jeevan Chalke

If we ever support unix sockets on Windows, we should use "" rather than
'' for zero-length strings on the command-line, so use that.

Add ability for to_char() to output the timezone's UTC offset (OF).  We
already have the ability to return the timezone abbeviation (TZ/tz).
Per request from Andrew Dunstan

A VPATH build will be performed when the module's make file path is not
the current directory or when USE_VPATH is set.

This will assist packagers and others who prefer to build without
polluting the source directories.

There is still a bit of work to do here, notably documentation, but it's
probably a good idea to commit what we have so far and let people test
it out on their modules.

Cédric Villemain, with an addition from me.

Update Linux Standard Base Core Specification 3.1 URL mention in pg_ctl
comments.

The -h option was not supported by many tools, and not documented, so
remove them for consistency from pg_upgrade, pg_test_fsync, and
pg_test_timing.

The pglz compressor has a significant startup cost, because it has to
initialize to zeros the history-tracking hash table. On a 64-bit system, the
hash table was 64kB in size. While clearing memory is pretty fast, for very
short inputs the relative cost of that was quite large.

This patch alleviates that in two ways. First, instead of storing pointers
in the hash table, store 16-bit indexes into the hist_entries array. That
slashes the size of the hash table to 1/2 or 1/4 of the original, depending
on the pointer width. Secondly, adjust the size of the hash table based on
input size. For very small inputs, you don't need a large hash table to
avoid collisions.

Review by Amit Kapila.

We don't normally bother retrying when the number of bytes written by
write() is short of what was requested. It is generally assumed that a
write() to disk doesn't return short, unless you run out of disk space.
While writing the WAL, however, it seems prudent to try a bit harder,
because a failure leads to PANIC. The write() is also much larger than most
write()s in the backend (up to wal_buffers), so there's more room for
surprises.

Also retry on EINTR. All signals used in the backend are flagged SA_RESTART
nowadays, so it shouldn't happen, but better to be defensive.

C++ is more picky about comparing signed and unsigned integers.

mm_strdup() is provided to check errors from strdup(), but some places
were failing to use it.

ginCompareItemPointers function is called heavily in gin index scans -
inlining it speeds up some kind of queries a lot.

Set errcode to ERRCODE_LOCK_NOT_AVAILABLE

Zoltán Bsöszörményi

Allow constraint attributes to be altered,
so the default setting of NOT DEFERRABLE
can be altered to DEFERRABLE and back.

Review by Abhijit Menon-Sen

If -U (user) is specified, pass the username into the created analyze
script.
Per request from Ray Stell

-h (help) is not needed;  pg_upgrade already supports --help and -?,
which is consistent with other tools.

Previous code had old/new prefixes on option values, e.g.
--old-datadir=OLDDATADIR.  Remove them, for simplicity;  now:
--old-datadir=DATADIR.  Also update docs to do the same.

On immediate shutdown, or during a restart-after-crash sequence,
postmaster used to send SIGQUIT (and then abandon ship if shutdown); but
this is not a good strategy if backends don't die because of that
signal.  (This might happen, for example, if a backend gets tangled
trying to malloc() due to gettext(), as in an example illustrated by
MauMau.)  This causes problems when later trying to restart the server,
because some processes are still attached to the shared memory segment.

Instead of just abandoning such backends to their fates, we now have
postmaster hang around for a little while longer, send a SIGKILL after
some reasonable waiting period, and then exit.  This makes immediate
shutdown more reliable.

There is disagreement on whether it's best for postmaster to exit after
sending SIGKILL, or to stick around until all children have reported
death.  If this controversy is resolved differently than what this patch
implements, it's an easy change to make.

Bug reported by MauMau in message 20DAEA8949EC4E2289C6E8E58560DEC0@maumau

MauMau and Álvaro Herrera

Change -u (user) option to -U, for consistency with other tools like
pg_dump and psql.  Also expand --user to --username, again for
consistency.
BACKWARD INCOMPATIBILITY

This results in a slightly less specific error message when OVER
is used in a context where we don't accept window functions, but
per discussion, it's worth it to get the benefit of not needing
to reserve this keyword any more.  This same refactoring will
also let us avoid reserving some other keywords that we expect
to add in upcoming patches (specifically, IGNORE, RESPECT, and
FILTER).

Troels Nielsen, with minor changes by me

In some cases, the use of these macros may be preferable to Assert()
or AssertMacro(), since this way the caller can set the trap message.

Andres Freund and Robert Haas

On many platforms the OS will round the sleep time to millisecond
resolution, but there is no reason for us to pre-emptively round the
argument to pg_usleep.

When the delay was measured in milliseconds and started from 1 ms, it
sometimes took many attempts until the logic that increases the delay by
multiplying with a random value between 1 and 2 actually managed to bump it
from 1 ms to 2 ms. That lead to a sequence of 1 ms waits until the delay
started to increase. This wasn't really a problem but it looked odd if you
observed the waits. There is no measurable difference in performance, but
it's more readable this way.

Jeff Janes

I added some more functionality to it in 0ac5ad51 but neglected to
add it to the docs.

Per Peter Eisentraut in message
1367112171.32604.4.camel@vanquo.pezone.net

I introduced these new fields in 0ac5ad51 but neglected to add them
to the system catalogs section of the docs.

Per Thom Brown in message
CAA-aLv7UiO=Whiq3MVbsEqSyQRthuX8Tb_RLyBuQt0KQBp=6EQ@mail.gmail.com

The MaxAllocSize guard is convenient for most callers, because it
reduces the need for careful attention to overflow, data type selection,
and the SET_VARSIZE() limit.  A handful of callers are happy to navigate
those hazards in exchange for the ability to allocate a larger chunk.
Introduce MemoryContextAllocHuge() and repalloc_huge().  Use this in
tuplesort.c and tuplestore.c, enabling internal sorts of up to INT_MAX
tuples, a factor-of-48 increase.  In particular, B-tree index builds can
now benefit from much-larger maintenance_work_mem settings.

Reviewed by Stephen Frost, Simon Riggs and Jeff Janes.