Previous changes misconstrued pg_upgrade internals
causing build farm breakages.

The value is not used anywhere in code, but will
allow future changes to the checksum version
should that become necessary in the future.

logs the heap page and sets the LSN. Otherwise a
checkpoint could occur between those actions and
leave us in an inconsistent state.

Jeff Davis

Ants Aasma and Jeff Davis

This code was left over from when pg_upgrade paid attention to PGPORT.
Now it would only affects the regression test run before the test run of
pg_upgrade.  You can still set PGPORT for that, but there is no reason
to have the test driver default it to 50432.

This reverts commit 87306184.  The
behavior in certain cases is still being debated, and it's too late to
solve this before beta.

This patch gets rid of the concept of, and infrastructure for,
non-canonical PathKeys; we now only ever create canonical pathkey lists.

The need for non-canonical pathkeys came from the desire to have
grouping_planner initialize query_pathkeys and related pathkey lists before
calling query_planner.  However, since query_planner didn't actually *do*
anything with those lists before they'd been made canonical, we can get rid
of the whole mess by just not creating the lists at all until the point
where we formerly canonicalized them.

There are several ways in which we could implement that without making
query_planner itself deal with grouping/sorting features (which are
supposed to be the province of grouping_planner).  I chose to add a
callback function to query_planner's API; other alternatives would have
required adding more fields to PlannerInfo, which while not bad in itself
would create an ABI break for planner-related plugins in the 9.2 release
series.  This still breaks ABI for anything that calls query_planner
directly, but it seems somewhat unlikely that there are any such plugins.

I had originally conceived of this change as merely a step on the way to
fixing bug #8049 from Teun Hoogendoorn; but it turns out that this fixes
that bug all by itself, as per the added regression test.  The reason is
that now get_eclass_for_sort_expr is adding the ORDER BY expression at the
end of EquivalenceClass creation not the start, and so anything that is in
a multi-member EquivalenceClass has already been created with correct
em_nullable_relids.  I am suspicious that there are related scenarios in
which we still need to teach get_eclass_for_sort_expr to compute correct
nullable_relids, but am not eager to risk destabilizing either 9.2 or 9.3
to fix bugs that are only hypothetical.  So for the moment, do this and
stop here.

Back-patch to 9.2 but not to earlier branches, since they don't exhibit
this bug for lack of join-clause-movement logic that depends on
em_nullable_relids being correct.  (We might have to revisit that choice
if any related bugs turn up.)  In 9.2, don't change the signature of
make_pathkeys_for_sortclauses nor remove canonicalize_pathkeys, so as
not to risk more plugin breakage than we have to.

Patch b19e4250 attempted to
preserve existing behavior regarding statistics generation in the
case that a truncation attempt was canceled due to lock conflicts.
It failed to do this accurately in two regards: (1) autovacuum had
previously generated statistics if the truncate attempt failed to
initially get the lock rather than having started the attempt, and
(2) the VACUUM ANALYZE command had always generated statistics.

Both of these changes were unintended, and are reverted by this
patch.  On review, there seems to be consensus that the previous
failure to generate statistics when the truncate was terminated
was more an unfortunate consequence of how that effort was
previously terminated than a feature we want to keep; so this
patch generates statistics even when an autovacuum truncation
attempt terminates early.  Another unintended change which is kept
on the basis that it is an improvement is that when a VACUUM
command is truncating, it will the new heuristic for avoiding
blocking other processes, rather than keeping an
AccessExclusiveLock on the table for however long the truncation
takes.

Per multiple reports, with some renaming per patch by Jeff Janes.

Backpatch to 9.0, where problem was created.

Previously, libpq and the backend had opposite ideas about whether
it was necessary for the client to send a CopyDone message after
receiving an ErrorResponse, making it impossible to cleanly exit
COPY BOTH mode.  Fix libpq so that works correctly, adopting the
backend's notion that an ErrorResponse kills the copy in both
directions.

Adjust receivelog.c to avoid a degradation in the quality of the
resulting error messages.  libpqwalreceiver.c is already doing
the right thing, so no adjustment needed there.

Add an explicit statement to the documentation explaining how
this part of the protocol is supposed to work, in the hopes of
avoiding future confusion in this area.

Since the consequences of all this confusion are very limited,
especially in the back-branches where no client ever attempts
to exit COPY BOTH mode without closing the connection entirely,
no back-patch.

Isolate checksum calculation to its own module, so that bufpage
knows little if anything about the details of the calculation.

This implementation is a modified FNV-1a hash checksum, details
of which are given in the new checksum.c header comments.

Basic implementation only, so we fix the output value.

Later related commits will add version numbers to pg_control,
compiler optimization flags and memory barriers.

Ants Aasma, reviewed by Jeff Davis and Simon Riggs

Choose a saner ordering of parameters (adding a new input param after
the output params seemed a bit random), update the function's header
comment to match reality (cmon folks, is this really that hard?),
get rid of useless and sloppily-defined distinction between
PROCESS_UTILITY_SUBCOMMAND and PROCESS_UTILITY_GENERATED.

We mustn't run any of the event-trigger support code when handling
utility statements like START TRANSACTION or ABORT, because that code
may need to refresh event-trigger cache data, which requires being
inside a valid transaction.  (This mistake explains the consistent
build failures exhibited by the CLOBBER_CACHE_ALWAYS buildfarm members,
as well as some irreproducible failures on other members.)

The least messy fix seems to be to break standard_ProcessUtility into two
functions, one that handles all the statements not supported by event
triggers, and one that contains the event-trigger support code and handles
the statements that are supported by event triggers.

This change also fixes several inconsistencies, such as four cases where
support had been installed for "ddl_event_start" but not "ddl_event_end"
triggers, plus the fact that InvokeDDLCommandEventTriggersIfSupported()
paid no mind to isCompleteQuery.

Dimitri Fontaine and Tom Lane

Move checking for unscannable matviews into ExecOpenScanRelation, which is
a better place for it first because the open relation is already available
(saving a relcache lookup cycle), and second because this eliminates the
problem of telling the difference between rangetable entries that will or
will not be scanned by the query.  In particular we can get rid of the
not-terribly-well-thought-out-or-implemented isResultRel field that the
initial matviews patch added to RangeTblEntry.

Also get rid of entirely unnecessary scannability check in the rewriter,
and a bogus decision about whether RefreshMatViewStmt requires a parse-time
snapshot.

catversion bump due to removal of a RangeTblEntry field, which changes
stored rules.

The old phrasing appeared to imply that the failure was terminal.
Improve that by indicating that archiving will be tried again later.

ORDER BY expressions were being treated the same as regular aggregate
arguments for purposes of collation determination, but really they should
not affect the aggregate's collation at all; only collations of the
aggregate's regular arguments should affect it.

In many cases this mistake would lead to incorrectly throwing a "collation
conflict" error; but in some cases the corrected code will silently assign
a different collation to the aggregate than before, for example
	agg(foo ORDER BY bar COLLATE "x")
which will now use foo's collation rather than "x" for the aggregate.
Given this risk and the lack of field complaints about the issue, it
doesn't seem prudent to back-patch.

In passing, rearrange code in assign_collations_walker so that we don't
need multiple copies of the standard logic for computing collation of a
node with children.  (Previously, CaseExpr duplicated the standard logic,
and we would have needed a third copy for Aggref without this change.)

Andrew Gierth and David Fetter

Ensure that user created rows in extension tables get dumped if the table is explicitly requested, either with a -t/--table switch of the table itself, or by -n/--schema switch of the schema containing the extension table. Patch reviewed by Vibhor Kumar and Dimitri Fontaine.

Backpatched to 9.1 when the extension management facility was added.

There's probably no real bug here at present, so not backpatching.
But it seems good to make these bits consistent with the rest of
libpq, so as to avoid future surprises.

Patch by me.  Review by Tom Lane.

There was a high probability of two or more concurrent C.I.C. commands
deadlocking just before completion, because each would wait for the others
to release their reference snapshots.  Fix by releasing the snapshot
before waiting for other snapshots to go away.

Per report from Paul Hinze.  Back-patch to all active branches.

Peter Geoghegan

Erwin Brandstetter and Pavel Stěhule

On non-Windows systems, sys/time.h was pulled in by portability/instr_time.h,
which pulled in time.h. We certainly should include time.h directly, since
we're using time(2), but the indirect include masked the problem on most
platforms.

Andres Freund

This was due to incomplete implementation of rowcount reporting
for RMV, which was due to initial waffling on whether it should
be provided.  It seems unlikely to be a useful or universally
available  number as more sophisticated techniques for maintaining
matviews are added, so remove the partial support rather than
completing it.

Per report of Jeevan Chalke, but with a different fix

Continue to allow a request for synchronous
checkpoints as a mechanism in case of problems.

Erikjan Rijkers

Adrian Schreyer

Alvaro Herrera

This is new in 9.3devel.

Andres Freund

Erwin Brandstetter

LANGUAGE 'plpgsql' no longer works.  The single quotes need to be
removed.

Erwin Brandstetter