and fsync WAL at convenient intervals.  For the moment it just tries to
offload this work from backends, but soon it will be responsible for
guaranteeing a maximum delay before asynchronously-committed transactions
will be flushed to disk.

This is a portion of Simon Riggs' async-commit patch, committed to CVS
separately because a background WAL writer seems like it might be a good idea
independently of the async-commit feature.  I rebased walwriter.c on
bgwriter.c because it seemed like a more appropriate way of handling signals;
while the startup/shutdown logic in postmaster.c is more like autovac because
we want walwriter to quit before we start the shutdown checkpoint.

I/O utilization, per discussion.

While at it, lower the autovacuum vacuum and analyze threshold values to 50
tuples.  It is a bit higher (i.e. more conservative) than what I originally
proposed but much better than the old values for small tables.

whereas in the backend it's been 64 for some time.  Hasn't mattered
because no actual tags exceed 40 bytes, but for consistency they should
be alike.

In passing, change functions that passedin both PGconn and
parts of it to just pass in the PGconn.

Jim Nasby.

against a Unix server, and Windows-specific server-side authentication
using SSPI "negotiate" method (Kerberos or NTLM).

Only builds properly with MSVC for now.

log_min_error_statement is active and there is some problem in logging the
current query string; for example, that it's too long to include in the log
message without running out of memory.  This problem has existed since the
log_min_error_statement feature was introduced.  No doubt the reason it
wasn't detected long ago is that 8.2 is the first release that defaults
log_min_error_statement to less than PANIC level.
Per report from Bill Moran.

Per request from Luca Ferrari.

truncated relation was deleted later in the WAL sequence.  Since replay
normally auto-creates a relation upon its first reference by a WAL log entry,
failure is seen only if the truncate entry happens to be the first reference
after the checkpoint we're restarting from; which is a pretty unusual case but
of course not impossible.  Fix by making truncate entries auto-create like
the other ones do.  Per report and test case from Dharmendra Goyal.

lot more sensible if we check the chunk-output case first.  Not
back-patched since it's just a cosmetic improvement.

when handed an invalidly-encoded pattern.  The previous coding could get
into an infinite loop if pg_mb2wchar_with_len() returned a zero-length
string after we'd tested for nonempty pattern; which is exactly what it
will do if the string consists only of an incomplete multibyte character.
This led to either an out-of-memory error or a backend crash depending
on platform.  Per report from Wiktor Wodecki.

be catching stderr output, and we are not ourselves the
syslogger. Otherwise, go directly to stderr.
Bug noticed by Tom Lane.
Backpatch as far as 8.0.

Minor rearrangements to make a few tests in a more logical order.

a MIN or MAX aggregate call into an indexscan: the initplan is being made at
the current query nesting level and so we shouldn't increment query_level.
Though usually harmless, this mistake could lead to bogus "plan should not
reference subplan's variable" failures on complex queries.  Per bug report
from David Sanchez i Gregori.

some platforms and possibly a bug.  Per report from Stefan and subsequent
discussion.

Patch from Tom.

>
> 	o Allow GLOBAL temporary tables to exist as empty by default in
> 	  all sessions
>
> 	  http://archives.postgresql.org/pgsql-hackers/2007-07/msg00006.php
>

referencing table does not change the tuple's FK column(s), we don't bother
to check the PK table since the constraint was presumably already valid.
However, the check is still necessary if the tuple was inserted by our own
transaction, since in that case the INSERT trigger will conclude it need not
make the check (since its version of the tuple has been deleted).  We got this
right for simple cases, but not when the insert and update are in different
subtransactions of the current top-level transaction; in such cases the FK
check would never be made at all.  (Hence, problem dates back to 8.0 when
subtransactions were added --- it's actually the subtransaction version of a
bug fixed in 7.3.5.)  Fix, and add regression test cases.  Report and fix by
Affan Salman.

meaningful site.

based in part on an earlier patch from Trevor Hardcastle, and reviewed
by myself.

been broken since forever, but was not noticed because people seldom look
at raw parse trees.  AFAIK, no impact on users except that debug_print_parse
might fail; but patch it all the way back anyway.  Per report from Jeff Ross.

> * Allow multiple indexes to be created concurrently, ideally via a
>   single heap scan, and have a restore of a pg_dump somehow use it
>
>   http://archives.postgresql.org/pgsql-general/2007-05/msg01274.php

Small blank line additions.

on other errors.

and add a note about why.  This is not tremendously important right now,
probably, but it will get more urgent if NUM_BUFFER_PARTITIONS is increased
as much as proposed.

partition locks in reverse order.

--enable-debug is used, to avoid complaints about debugging and
optimization being mutually exclusive. Patch from Stefan Kaltenbrunner.

name.  With this patch, it is always possible for the user to qualify a
plpgsql variable name if needed to avoid ambiguity.  While there is much more
work to be done in this area, this simple change removes one unnecessary
incompatibility with Oracle.  Per discussion.

int not unsigned int.  Third try to get grebe building without warnings...

spaces in them.

ISHIDA Akio

nattering about casting away volatile.  Losers.

TAS support are properly declared.

for 'bool'.  Per buildfarm warnings.

a warning but was outright wrong.