Currently we don't need to update the pg_tablespace catalog
after redefining the symbolic links to the tablespaces
because pg_tablespace.spclocation column was removed in
PostgreSQL 9.2.

Back patch to 9.2 where pg_tablespace.spclocation was removed.

Ian Barwick, with minor change by me.

consultation with word definitions.

Backpatch to 9.2.

As noted by Thom Brown, this confuses the DocBook index processor; it
fails to merge entries that differ only in whitespace, and sorts them
unexpectedly as well.  Seems like a toolchain bug, but I'm not going to
hold my breath waiting for a fix.

Note: easiest way to find these is to look for double spaces in HTML.index.

The endterm attribute is mainly useful when the toolchain does not support
automatic link target text generation for a particular situation.  In  the
past, this was required by the man page tools for all reference page links,
but that is no longer the case, and it now actually gets in the way of
proper automatic link text generation.  The only remaining use cases are
currently xrefs to refsects.

plpgsql is now installed by default.

pg_ctl gets a new mode that runs initdb.  Adjust the documentation a bit to
not assume that initdb is the only way to run database cluster initialization.
But don't replace initdb as the canonical way.

Author: Zdenek Kotala <Zdenek.Kotala@Sun.COM>

must be used for the new database, except when copying from template0.
This is the same rule that we now enforce for locale settings, and it has
the same motivation: databases other than template0 might contain data that
would be invalid according to a different setting.  This represents another
step in a continuing process of locking down ways in which encoding violations
could occur inside the backend.  Per discussion of a few days ago.

In passing, fix pre-existing breakage of mbregress.sh, and fix up a couple
of ereport() calls in dbcommands.c that failed to specify sqlstate codes.

it seems more logical there.

tablespace(s) in which to store temp tables and temporary files.  This is a
list to allow spreading the load across multiple tablespaces (a random list
element is chosen each time a temp object is to be created).  Temp files are
not stored in per-database pgsql_tmp/ directories anymore, but per-tablespace
directories.

Jaime Casanova and Albert Cervera, with review by Bernd Helmle and Tom Lane.

appropriate.

Standard English uses "may", "can", and "might" in different ways:

        may - permission, "You may borrow my rake."

        can - ability, "I can lift that log."

        might - possibility, "It might rain today."

Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice.  Similarly, "It may crash" is better stated, "It might crash".

Also update two error messages mentioned in the documenation to match.

Backpatch to 8.2.

in PITR scenarios.  We now WAL-log the replacement of old XIDs with
FrozenTransactionId, so that such replacement is guaranteed to propagate to
PITR slave databases.  Also, rather than relying on hint-bit updates to be
preserved, pg_clog is not truncated until all instances of an XID are known to
have been replaced by FrozenTransactionId.  Add new GUC variables and
pg_autovacuum columns to allow management of the freezing policy, so that
users can trade off the size of pg_clog against the amount of freezing work
done.  Revise the already-existing code that forces autovacuum of tables
approaching the wraparound point to make it more bulletproof; also, revise the
autovacuum logic so that anti-wraparound vacuuming is done per-table rather
than per-database.  initdb forced because of changes in pg_class, pg_database,
and pg_autovacuum catalogs.  Heikki Linnakangas, Simon Riggs, and Tom Lane.

symlink is kept for now for compatibility.  To call single-user mode, use
postgres --single.

The former approach used ExclusiveLock on pg_database, which being a
cluster-wide lock meant only one of these operations could proceed at
a time; worse, it also blocked all incoming connections in ReverifyMyDatabase.
Now that we have LockSharedObject(), we can use locks of different types
applied to databases considered as objects.  This allows much more
flexible management of the interlocking: two CREATE DATABASEs need not
block each other, and need not block connections except to the template
database being used.  Similarly DROP DATABASE doesn't block unrelated
operations.  The locking used in flatfiles.c is also much narrower in
scope than before.  Per recent proposal.

unlike template0 and template1 does not have any special status in
terms of backend functionality.  However, all external utilities such
as createuser and createdb now connect to "postgres" instead of
template1, and the documentation is changed to encourage people to use
"postgres" instead of template1 as a play area.  This should fix some
longstanding gotchas involving unexpected propagation of database
objects by createdb (when you used template1 without understanding
the implications), as well as ameliorating the problem that CREATE
DATABASE is unhappy if anyone else is connected to template1.
Patch by Dave Page, minor editing by Tom Lane.  All per recent
pghackers discussions.

reference page for SQL commands, so that the link text is italicized.

reasons I outlined in pghackers a few days ago.

Also, undo someone's overly optimistic decision to reduce tuple state
checks from if (...) elog() to Asserts.  If I trusted this code more,
I might think it was a good idea to disable these checks in production
installations.  But I don't.

clause implicitly whenever one is not given explicitly.  Remove concept
of a schema having an associated tablespace, and simplify the rules for
selecting a default tablespace for a table or index.  It's now just
(a) explicit TABLESPACE clause; (b) default_tablespace if that's not an
empty string; (c) database's default.  This will allow pg_dump to use
SET commands instead of tablespace clauses to determine object locations
(but I didn't actually make it do so).  All per recent discussions.

creation of user-defined tablespaces with names starting with 'pg_', as
per suggestion of Chris K-L.  Also install admin-guide tablespace
documentation from Gavin.

There are various things left to do: contrib dbsize and oid2name modules
need work, and so does the documentation.  Also someone should think about
COMMENT ON TABLESPACE and maybe RENAME TABLESPACE.  Also initlocation is
dead, it just doesn't know it yet.

Gavin Sherry and Tom Lane.

$Header: -> $PostgreSQL Changes ...

vague cross-references with real links.