gcc 4.6 complains about these because of the new option
-Wunused-but-set-variable which comes in with -Wall, so cast them to
void, which avoids the warning.

Flexible array members are a C99 feature that avoids "cheating" in the
declaration of variable-length arrays at the end of structs.  With
Autoconf support, this should be transparent for older compilers.

We start with one use in gist.h because gcc 4.6 started to raise a
warning there.  Over time, it can be expanded to other places in the
source, but they will likely need some review of sizeof and offsetof
usage.  The current change in gist.h appears to be safe in this
regard.

SSI is based on, as well as the optimizations about relative commit times
and read-only transactions. Plus a bunch of other misc fixes and
improvements.

Dan Ports

Kevin Grittner

Btree pages were recycled after VACUUM deletes all records on a
page and then a subsequent VACUUM occurs after the RecentXmin
horizon is reached. Using RecentXmin meant that we did not respond
correctly to the user controls provide to avoid Hot Standby
conflicts and so spurious conflicts could be generated in some
workload combinations. We now reuse pages only when we reach
RecentGlobalXmin, which can be much later in the presence of long
running queries and is also controlled by vacuum_defer_cleanup_age
and hot_standby_feedback.

Noah Misch and Simon Riggs

Per recommendation from Peter.  Neither choice is bulletproof, but this
is the existing style and it does help prevent unexpected environment
variable substitution.

The initial commit of the ALTER TABLE ADD FOREIGN KEY NOT VALID feature
failed to support labeling such constraints as deferrable.  The best fix
for this seems to be to fold NOT VALID into ConstraintAttributeSpec.
That's a bit more general than the documented syntax, but it allows
better-targeted syntax error messages.

In addition, do some mostly-but-not-entirely-cosmetic code review for
the whole NOT VALID patch.

This oversight could result in a tuplestore using much more than the
intended amount of memory.  It would only happen in a code path that loaded
a tuplestore via tuplestore_putvalues(), and many of those won't emit huge
amounts of data; but cases such as holdable cursors and plpgsql's RETURN
NEXT command could have the problem.  The fix ensures that the tuplestore
will switch to write-to-disk mode when it overruns work_mem.

The potential overrun was finite, because we would still count the space
used by the tuple pointer array, so the tuplestore code would eventually
flip into write-to-disk mode anyway.  When storing wide tuples we would
go far past the expected work_mem usage before that happened; but this
may account for the lack of prior reports.

Back-patch to 8.4, where tuplestore_putvalues was introduced.

Per bug #6061 from Yann Delorme.

The short-form -z switch didn't work, for lack of telling getopt_long
about it; and even if specified long-form, it failed to do anything,
because the various tests elsewhere in the file would take
Z_DEFAULT_COMPRESSION (which is -1) as meaning "don't compress".

Per bug #6060 from Shigehiro Honda, though I editorialized on his patch
a bit.

the marked-for-death flag. It was only set for a fleeting moment while a
transaction was being cleaned up at rollback. All the places that checked
for the rolled-back flag should also check the marked-for-death flag, as
both flags mean that the transaction will roll back. I also renamed the
marked-for-death into "doomed", which is a lot shorter name.

snapshots, like in REINDEX, are basically non-transactional operations. The
DDL operation itself might participate in SSI, but there's separate
functions for that.

Kevin Grittner and Dan Ports, with some changes by me.

This matches what \d actually accepts.

This has always been true, it was just never documented.

the same file system, and that authentication should lock out normal
users.

Per suggestsion from #postgresql irc channel.

Backpatch to 9.1.

Apparently there is no buildfarm critter exercising this case after all,
because it fails in several places.  With this patch, build, install,
check-world, and installcheck-world pass for me on OS X.

The variable became obsolete in commit
68739ba8, but only gcc 4.6 shows the
warning.

We don't have to remove the column if no one is bothered, but it's
useful to comment on it in case someone looks for it in newer
standards versions.

Per note from Tom

... when talking about how good they are in replacement of bulk DELETE
in partitioned setups.

The original wording was a bit confusing.

Per an observation from David Wheeler.

Per a gripe from Tom Lane.

renumbered the resource managers. This should fix the buildfarm..

is added to the end, and existing resource managers keep their old ids.
We're not going to guarantee on-disk compatibility for 2PC state files over
major releases, but it seems better to avoid changing the ids them anyway.
It will help anyone who might want to write external tools to inspect the
state files to work with files from different versions, if nothing else.
Per complaint from Tom Lane.

We have a SCM, so we don't need to keep old versions of files around.

"must".

Spotted by Jaime Casanova

The previous wording wasn't explicit enough, which could misled readers
into thinking that the locks acquired are more restricted in nature than
they really are.  The resulting optimism can be damaging to morale when
confronted with reality, as has been observed in the field.

Greg Smith

This is more consistent with what we do elsewhere, and hopefully avoids
creating the perception that current_schemas takes no arguments.

As suggested by Brendan Jurd

As suggested by Grzegorz Szpetkowski.

Brendan Jurd

Fujii Masao

Noted by Daniele Varrazzo.

Fujii Masao

Shigeru Hanada, with some additional wordsmithing by me

Kevin Grittner

Shigeru Hanada, with a minor grammar correction.

The old code creates three separate arrays when only one is needed,
using two different shmem allocation functions for no obvious reason.
It also strangely splits up the initialization of AuxilaryProcs
between the top and bottom of the function to no evident purpose.

Review by Tom Lane.