Allow messages to be sent at different times, and greatly reduce
the frequency of hot standby feedback. Refactor to allow additional
message types.

Kevin Grittner

Applied a patch by Zoltán Böszörményi that makes ecpg's parser accept dynamic cursornames even in WHERE CURRENT OF clauses.

Shigeru HANADA

They share the same locking namespace with the existing session-level
advisory locks, but they are automatically released at the end of the
current transaction and cannot be released explicitly via unlock
functions.

Marko Tiikkaja, reviewed by me.

More generally, arrays are turned in Perl array references, and row and
composite types are turned into Perl hash references.  This is done
recursively, in a way that's natural to every Perl programmer.

To avoid a backwards compatibility hit, the string representation of
each structure is also available if the function requests it.

Authors: Alexey Klyukin and Alex Hunsaker.
Some code cleanups by me.

This allows the user to change the path to be used more easily.
Also, change URL in README.

ts_typanalyze.c computes MCE statistics as fractions of the non-null rows,
which seems fairly reasonable, and anyway changing it in released versions
wouldn't be a good idea.  But then ts_selfuncs.c has to account for that.
Failure to do so results in overestimates in columns with a significant
fraction of null documents.  Back-patch to 8.4 where this stuff was
introduced.

Jesper Krogh

Update script was being sloppy about two functions that have been changed
since 9.0.

Take care of a couple of discrepancies between what you get from a fresh
install and what the first-draft update-from-unpackaged scripts produced.

The initial version of the update-from-unpackaged script neglected to
include the <> operators that were added to the opclasses during 9.1.
To make this script produce the same final state as the regular install
script, use the same ALTER OPERATOR FAMILY trick as in pg_trgm.

Peter Eisentraut, reviewed by Steve Singer, Alvaro Herrera, and me.

Simon Riggs reports that rnode.dbNode and rnode.spcNode were
generating unused variable warnings on gcc 4.4.3 with CFLAGS=-O1

Erik Rijkers

Take care of some loose ends in the update-from-unpackaged script, and
apply some ugly hacks to ensure that it produces the same catalog state
as the fresh-install script.  Per discussion, this seems like a safer
plan than having two different catalog states that both call themselves
"pg_trgm 1.0", even if it's not immediately clear that the subtle
differences would ever matter.

Also, fix the stub function gin_extract_trgm() so that it works instead
of just bleating.  Needed because this function will get called during a
regular dump and reload, if there are any indexes using its opclass.
The user won't have an opportunity to update the extension till later,
so telling him to do so is unhelpful.

unique exception, or if not used in read committed transaction mode.

because concat() is a built-in function.

Erik Rijkers

Stephen Frost, somewhat rewritten by me

Thom Brown

Instead, document how to build it manually.

Per discussion.  KaiGai Kohei, with some wordsmithing by me.

Doesn't anybody around here pay attention to compiler warnings?

That function was supposing that indexoid == 0 for a hypothetical index,
but that is not likely to be true in any non-toy implementation of an index
adviser, since assigning a fake OID is the only way to know at EXPLAIN time
which hypothetical index got selected.  Fix by adding a flag to
IndexOptInfo to mark hypothetical indexes.  Back-patch to 9.0 where
get_actual_variable_range() was added.

Gurjeet Singh

These are needed to support reloading dumps of 9.0 installations containing
contrib/intarray or contrib/tsearch2.  Since not only regular dump/reload
but binary upgrade would fail, it seems worth the trouble to carry these
stubs for awhile.  Note that the contrib opclasses referencing these
functions will still work fine, since GIN doesn't actually pay any
attention to the declared signature of a support function.

This was previously not very useful, but with many people customizing
the linestyle, it is nice for a consistent appearance.

When testing the stderr produced by various thread-support flags, also
run a compilation in addition to a link, because clang warns on
certain flags when compiling but not when linking.

The first argument of PyEval_EvalCode() was changed from PyCodeObject*
to PyObject* because of PEP 384.

always zeros.  Also no need to free memory before we exit.

Standby optionally sends back information about oldestXmin of queries
which is then checked and applied to the WALSender's proc->xmin.
GetOldestXmin() is modified slightly to agree with GetSnapshotData(),
so that all backends on primary include WALSender within their snapshots.
Note this does nothing to change the snapshot xmin on either master or
standby. Feedback piggybacks on the standby reply message.
vacuum_defer_cleanup_age is no longer used on standby, though parameter
still exists on primary, since some use cases still exist.

Simon Riggs, review comments from Fujii Masao, Heikki Linnakangas, Robert Haas

This seems a bit more user-friendly.

Per report from, and discussion with, Fujii Masao.

(I'm not entirely sure that we've finished bikeshedding the syntax details,
but the functionality seems OK.)

Pavel Stehule, reviewed by Stephen Frost and Tom Lane

Fujii Masao, reviewed by Robert Haas, Stephen Frost, and Magnus Hagander.

They are expected to be used by extension modules like file_fdw.
There are no user-visible changes.

Itagaki Takahiro
Reviewed and tested by Kevin Grittner and Noah Misch.

output.

Normally, pg_dump summarily excludes functions in pg_catalog from
consideration.  However, some extensions may create functions in pg_catalog
(adminpack already does that, and extensions for procedural languages will
likely do it too).  In binary-upgrade mode, we have to dump such functions,
or the extension will be incomplete after upgrading.  Per experimentation
with adminpack.

Recent releases had a check on rel->rd_refcnt in heap_drop_with_catalog,
but failed to cover the possibility of pending trigger events at DROP time.
(Before 8.4 we didn't even check the refcnt.)  When the trigger events were
eventually fired, you'd get "could not open relation with OID nnn" errors,
as in recent report from strk.  Better to throw a suitable error when the
DROP is attempted.

Also add a similar check in DROP INDEX.

Back-patch to all supported branches.