pg_basebackup: Small message punctuation improvements
Rename SQL feature S403 to ARRAY_MAX_CARDINALITY

In an earlier version of the standard, this was called just
"MAX_CARDINALITY".
Check if we've reached end-of-backup point also if no redo is required.

If you restored from a backup taken from a standby, and the last record in
the backup is the checkpoint record, ie. there is no redo required except
for the checkpoint record, we would fail to notice that we've reached the
end-of-backup point, and the database is consistent. The result was an
error "WAL ends before end of online backup". To fix, move the
have-we-reached-end-of-backup check into CheckRecoveryConsistency(), which
is already responsible for similar checks with minRecoveryPoint, and is
called in the right places.

Backpatch to 9.2, this check and bug did not exist before that.
Add pg_upgrade comment about mismatch error

Add comment stating that constraint and index names must match.
Don't set ThisTimeLineID in checkpointer & bgwriter during recovery.

We used to set it to the current recovery target timeline, but the recovery
target timeline can change during recovery, leaving ThisTimeLineID at an
old value. That seems worse than always leaving it at zero to begin with.

AFAICS there was no good reason to set it in the first place. ThisTimeLineID
is not needed in checkpointer or bgwriter process, until it's time to write
the end-of-recovery checkpoint, and at that point ThisTimeLineID is updated
anyway.
Follow TLI of last replayed record, not recovery target TLI, in walsenders.

Most of the time, the last replayed record comes from the recovery target
timeline, but there is a corner case where it makes a difference. When
the startup process scans for a new timeline, and decides to change recovery
target timeline, there is a window where the recovery target TLI has already
been bumped, but there are no WAL segments from the new timeline in pg_xlog
yet. For example, if we have just replayed up to point 0/30002D8, on
timeline 1, there is a WAL file called 000000010000000000000003 in pg_xlog
that contains the WAL up to that point. When recovery switches recovery
target timeline to 2, a walsender can immediately try to read WAL from
0/30002D8, from timeline 2, so it will try to open WAL file
000000020000000000000003. However, that doesn't exist yet - the startup
process hasn't copied that file from the archive yet nor has the walreceiver
streamed it yet, so walsender fails with error "requested WAL segment
000000020000000000000003 has already been removed". That's harmless, in that
the standby will try to reconnect later and by that time the segment is
already created, but error messages that should be ignored are not good.

To fix that, have walsender track the TLI of the last replayed record,
instead of the recovery target timeline. That way walsender will not try to
read anything from timeline 2, until the WAL segment has been created and at
least one record has been replayed from it. The recovery target timeline is
now xlog.c's internal affair, it doesn't need to be exposed in shared memory
anymore.

This fixes the error reported by Thom Brown. depesz the same error message,
but I'm not sure if this fixes his scenario.
Avoid using NAMEDATALEN in pg_upgrade

Because the client encoding might not match the server encoding,
pg_upgrade can't allocate NAMEDATALEN bytes for storage of database,
relation, and namespace identifiers.  Instead pg_strdup() the memory and
free it.

Also add C comment in initdb.c about safe NAMEDATALEN usage.
Fix recycling of WAL segments after switching timeline during recovery.

This was broken before, we would recycle old WAL segments on wrong timeline
after the recovery target timeline had changed, but my recent commit to
not initialize ThisTimeLineID at all in a standby's checkpointer process
broke this completely.

The problem is that when installing a recycled WAL segment as a future one,
ThisTimeLineID is used to construct the filename. To fix, always update
ThisTimeLineID to the current timeline being recovered, before recycling
WAL segments at a restartpoint.

This still leaves a small window where we might install WAL segments under
wrong timeline ID, if the timeline is changed just as we're about to start
recycling. Also, even if we're replaying timeline X at the momnent, there's
no guarantee that we'll need as many WAL segments on that timeline as we
recycle. We might be just about to reach the point where we switch to next
timeline, so might only need one more WAL segment on the current timeline.
We'll live with the waste in that situation.

Bug pointed out by Fujii Masao. 9.1 and 9.2 had the same issue, when
recovery target timeline was changed, but I committed a slightly different
version of this patch on those branches.
Fix pg_extension_config_dump() to handle update cases more sanely.

If pg_extension_config_dump() is executed again for a table already listed
in the extension's extconfig, the code was blindly making a new array entry.
This does not seem useful.  Fix it to replace the existing array entry
instead, so that it's possible for extension update scripts to alter the
filter conditions for configuration tables.

In addition, teach ALTER EXTENSION DROP TABLE to check for an extconfig
entry for the target table, and remove it if present.  This is not a 100%
solution because it's allowed for an extension update script to just
summarily DROP a member table, and that code path doesn't go through
ExecAlterExtensionContentsStmt.  We could probably make that case clean
things up if we had to, but it would involve sticking a very ugly wart
somewhere in the guts of dependency.c.  Since on the whole it seems quite
unlikely that extension updates would want to remove pre-existing
configuration tables, making the case possible with an explicit command
seems sufficient.

Per bug #7756 from Regina Obe.  Back-patch to 9.1 where extensions were
introduced.
Fix grammatical mistake in error message
Make some messages more consistent in style
Forgot to remove extern declaration of GetRecoveryTargetTLI()

Fujii Masao
Fix race condition if a file is removed while pg_basebackup is running.

If a relation file was removed when the server-side counterpart of
pg_basebackup was just about to open it to send it to the client, you'd
get a "could not open file" error. Fix that.

Backpatch to 9.1, this goes back to when pg_basebackup was introduced.
Fix sloppiness in the timeline switch over streaming replication patch.

Here's another attempt at fixing the logic that decides how far the WAL can
be streamed, which was still broken if the timeline changed while streaming.
You would get an assertion failure. The way the logic is now written is more
readable, too.

Thom Brown reported the assertion failure.
Fix documentation typo.

"GetForeignTableColumnOptions" should be "GetForeignColumnOptions".
Noted by Metin Döşlü.
Prevent failure when RowExpr or XmlExpr is parse-analyzed twice.

transformExpr() is required to cope with already-transformed expression
trees, for various ugly-but-not-quite-worth-cleaning-up reasons.  However,
some of its newer subroutines hadn't gotten the memo.  This accounts for
bug #7763 from Norbert Buchmuller: transformRowExpr() was overwriting the
previously determined type of a RowExpr during CREATE TABLE LIKE INCLUDING
INDEXES.  Additional investigation showed that transformXmlExpr had the
same kind of problem, but all the other cases seem to be safe.

Andres Freund and Tom Lane
Adjust many backend functions to return OID rather than void.

Extracted from a larger patch by Dimitri Fontaine.  It is hoped that
this will provide infrastructure for enriching the new event trigger
functionality, but it seems possibly useful for other purposes as
well.
Add function prototype from previous commit.
Fix more weird compiler messages caused
by unmatched function prototypes.

Andres Freund
Keep rd_newRelfilenodeSubid across overflow.
Teach RelationCacheInvalidate() to keep rd_newRelfilenodeSubid across rel cache
message overflows, so that behaviour is now fully deterministic.

Noah Misch