The "date" type supports a wider range of dates than int64 timestamps do.
However, there is pre-int64-timestamp code in the planner that assumes that
all date values can be converted to timestamp with impunity.  Fortunately,
what we really need out of the conversion is always a double (float8)
value; so even when the date is out of timestamp's range it's possible to
produce a sane answer.  All we need is a code path that doesn't try to
force the result into int64.  Per trouble report from David Rericha.

Back-patch to all supported versions.  Although this is surely a corner
case, there's not much point in advertising a date range wider than
timestamp's if we will choke on such values in unexpected places.

This is how it was documented originally, but several years ago somebody
decided that DEFAULT isn't a type of constraint.  Well, the grammar thinks
it is.  The documentation was wrong in two ways: it alleged that DEFAULT
had to appear before any other kind of constraint, and it alleged that you
can't prefix a DEFAULT clause with a "CONSTRAINT name" clause, when in fact
you can.  (The latter behavior probably isn't SQL-standard, but our grammar
has always allowed it.)

This patch responds to Fujii Masao's observation that the ALTER TABLE
documentation mistakenly implied that you couldn't include DEFAULT in
ALTER TABLE ADD COLUMN; though this isn't the way he proposed fixing it.

It must be added at the end of the ExecStatusType enum to avoid ABI
breakage compared to previous libpq versions.  Noted by Magnus.

Move the list of what's restricted to superusers into the table
itself, so it doesn't get missed again.

postmaster.pid file is larger than in previous major versions.
This is a bug introduced when I added lines to the file recently.

per change to the file for pg_ctl.

No longer needed now that bitand() and bitor() have been renamed.

This is to avoid use of the C++ keywords "bitand" and "bitor" in
the header file utils/varbit.h.  Note the functions' SQL-level
names are not changed, only their C-level names.

In passing, make some comments in varbit.c conform to project-standard
layout.

This is slower than the original coding but avoids the problem of
including files in an unpredictable order.  Aside from being more
trustworthy, we can get rid of some exclusions that were formerly
made for what turn out to be ordering or re-inclusion problems.

I also modified it to include libpq's exported files in the check.
ecpg should be included as well, but I'm unclear on which ecpg .h
files are meant to be included by clients.

Noted while experimenting with cpluspluscheck.

gram.h has ordering dependencies, which are satisfied when it's included
from gramparse.h, but might not be if it's pulled in directly.

"private" is a keyword in C++, so this breaks the poorly-enforced policy
that header files should be include-able in C++ code.  Per report from
Craig Ringer and some investigation with cpluspluscheck.

My previous commit, 85cff3ce on
2010-12-25, failed to update errcodes.sgml or plerrcodes.h.  This patch
corrects that oversight, per a gripe from Tom Lane, and also corrects
a typographical error.

Extracted from a much larger patch by Shigeru Hanada.

Allow vpath builds and regression tests to succeed on Mingw. Backpatch to release 8.4 - earlier releases would require more changes and it's not worth the trouble.

quotes are not required.  This now matches postgresql.conf's
specification of booleans.

port and socket directory into postmaster.pid, and have pg_ctl read from
that file, for use by PQping().

The order on the pg_dump/pg_dumpall man pages is not very strict, but
surely putting it under connection options was wrong.

The former is the option actually supported by these commands.

string". This is not really needed because the string gets copied to the output
untranslated anyway, but by adding this rule the lexer stays in sync with the
backend lexer.

cleanup stage to finish incomplete inserts or splits anymore. There was two
reasons for the cleanup step:

1. When a new tuple was inserted to a leaf page, the downlink in the parent
needed to be updated to contain (ie. to be consistent with) the new key.
Updating the parent in turn might require recursively updating the parent of
the parent. We now handle that by updating the parent while traversing down
the tree, so that when we insert the leaf tuple, all the parents are already
consistent with the new key, and the tree is consistent at every step.

2. When a page is split, we need to insert the downlink for the new right
page(s), and update the downlink for the original page to not include keys
that moved to the right page(s). We now handle that by setting a new flag,
F_FOLLOW_RIGHT, on the non-rightmost pages in the split. When that flag is
set, scans always follow the rightlink, regardless of the NSN mechanism used
to detect concurrent page splits. That way the tree is consistent right after
split, even though the downlink is still missing. This is very similar to the
way B-tree splits are handled. When the downlink is inserted in the parent,
the flag is cleared. To keep the insertion algorithm simple, when an
insertion sees an incomplete split, indicated by the F_FOLLOW_RIGHT flag, it
finishes the split before doing anything else.

These changes allow removing the whole "invalid tuple" mechanism, but I
retained the scan code to still follow invalid tuples correctly. While we
don't create any such tuples anymore, we want to handle them gracefully in
case you pg_upgrade a GiST index that has them. If we encounter any on an
insert, though, we just throw an error saying that you need to REINDEX.

The issue that got me into doing this is that if you did a checkpoint while
an insert or split was in progress, and the checkpoint finishes quickly so
that there is no WAL record related to the insert between RedoRecPtr and the
checkpoint record, recovery from that checkpoint would not know to finish
the incomplete insert. IOW, we have the same issue we solved with the
rm_safe_restartpoint mechanism during normal operation too. It's highly
unlikely to happen in practice, and this fix is far too large to backpatch,
so we're just going to live with in previous versions, but this refactoring
fixes it going forward.

With this patch, you don't get the annoying
'index "FOO" needs VACUUM or REINDEX to finish crash recovery' notices
anymore if you crash at an unfortunate moment.

off unless they guarantee that all writes to the BBU arrive in 8kB chunks.

Per discussion with Greg Smith

Noted by Thom Brown.

This function is like the PQserverVersion() function except
it returns the version of libpq, making it possible for a client
program or driver to determine which version of libpq is in
use at runtime, and not just at link time.

Suggested by Harald Armin Massa and several others.

It appears that this will be faster for all but the shortest strings;
at least one some platforms, memcmp() can use word-at-a-time comparisons.

Noah Misch, somewhat pared down.

Andreas Karlsson

On MacOS X, and apparently also on other BSD-derived systems, attaching
a debugger causes getppid() to return the pid of the debugging process
rather than the actual parent PID.  As a result, debugging the
autovacuum launcher, startup process, or WAL sender on such systems
causes it to exit, because the previous coding of PostmasterIsAlive()
detects postmaster death by testing whether getppid() == PostmasterPid.

Work around that behavior by checking the return value of getppid()
more carefully.  If it's PostmasterPid, the postmaster must be alive;
if it's 1, assume the postmaster is dead.  If it's any other value,
assume we've been debugged and fall through to the less-reliable
kill() test.

Review by Tom Lane.

This case can arise if a transaction has written data, but only to
temporary tables.  Loss of the commit record in case of a crash won't
matter, because the temporary tables will be lost anyway.

Reviewed by Heikki Linnakangas and Simon Riggs.

Jaime Casanova

Since we're not multithreaded it only provides marginally useful
information, and it does require a newer version of the Platform SDK
than we target. We may want to reconsider this in the future along
with a fix for MinGW.

eval_const_expressions() can replace CaseTestExprs with constants when
the surrounding CASE's test expression is a constant.  This confuses
ruleutils.c's heuristic for deparsing simple-form CASEs, leading to
Assert failures or "unexpected CASE WHEN clause" errors.  I had put in
a hack solution for that years ago (see commit
514ce7a3 of 2006-10-01), but bug #5794
from Peter Speck shows that that solution failed to cover all cases.

Fortunately, there's a much better way, which came to me upon reflecting
that Peter's "CASE TRUE WHEN" seemed pretty redundant: we can "simplify"
the simple-form CASE to the general form of CASE, by simply omitting the
constant test expression from the rebuilt CASE construct.  This is
intuitively valid because there is no need for the executor to evaluate
the test expression at runtime; it will never be referenced, because any
CaseTestExprs that would have referenced it are now replaced by constants.
This won't save a whole lot of cycles, since evaluating a Const is pretty
cheap, but a cycle saved is a cycle earned.  In any case it beats kluging
ruleutils.c still further.  So this patch improves const-simplification
and reverts the previous change in ruleutils.c.

Back-patch to all supported branches.  The bug exists in 8.1 too, but it's
out of warranty.