has a bad habit of launching multiple threads within the backend and thereby
causing all kinds of havoc.  Fortunately, we don't need it, and recent Tcl
versions provide an easy way to disable it.  Diagnosis and fix by
Steve Marshall, Paul Bayer, and Doug Knight of WSI Corporation.

but got lost from the version committed to main tree.  Per Greg Stark.

truncates a table.  Introduces race condition, as shown by buildfarm
failures.

> * -Consider shrinking expired tuples to just their headers
> * -Allow heap reuse of UPDATEd rows if no indexed columns are changed,
>   and old and new versions are on the same heap page

Not needed anymore:

< * Reuse index tuples that point to heap tuples that are not visible to
<   anyone?

columns, and the new version can be stored on the same heap page, we no longer
generate extra index entries for the new version.  Instead, index searches
follow the HOT-chain links to ensure they find the correct tuple version.

In addition, this patch introduces the ability to "prune" dead tuples on a
per-page basis, without having to do a complete VACUUM pass to recover space.
VACUUM is still needed to clean up dead index entries, however.

Pavan Deolasee, with help from a bunch of other people.

values. The previous coding essentially assumed that x = sqrt(x*x), which
does not hold for x < 0.

Thanks to Jie Zhang at Greenplum and Gavin Sherry for reporting this
issue.

database via builtin functions, as recently discussed on -hackers.

chr() now returns a character in the database encoding. For UTF8 encoded databases
the argument is treated as a Unicode code point. For other multi-byte encodings
the argument must designate a strict ascii character, or an error is raised,
as is also the case if the argument is 0.

ascii() is adjusted so that it remains the inverse of chr().

The two argument form of convert() is gone, and the three argument form now
takes a bytea first argument and returns a bytea. To cover this loss three new
functions are introduced:
. convert_from(bytea, name) returns text - converts the first argument from the
  named encoding to the database encoding
. convert_to(text, name) returns bytea - converts the first argument from the
  database encoding to the named encoding
. length(bytea, name) returns int - gives the length of the first argument in
  characters in the named encoding

per notice by Gregory Stark <stark@enterprisedb.com>

we'd dump core anyway immediately afterward if it were null; and it
seems to confuse some versions of icc into generating bad code.
Per report from Sergey Koposov.  Patched in HEAD only, for the moment,
since this is only likely to affect developers.

Seems to have been introduced in 8.1 by careless SECS_PER_DAY
search-and-replace.

no-longer-needed pages at the end of a table.  We thought we could throw away
pages containing HEAPTUPLE_DEAD tuples; but this is not so, because such
tuples very likely have index entries pointing at them, and we wouldn't have
removed the index entries.  The problem only emerges in a somewhat unlikely
race condition: the dead tuples have to have been inserted by a transaction
that later aborted, and this has to have happened between VACUUM's initial
scan of the page and then rechecking it for empty in count_nondeletable_pages.
But that timespan will include an index-cleaning pass, so it's not all that
hard to hit.  This seems to explain a couple of previously unsolved bug
reports.

Jun Kuwamura

>
> 	o Prevent long-lived temporary tables from causing frozen-xid
> 	  advancement starvation
>
> 	  http://archives.postgresql.org/pgsql-general/2007-06/msg01645.php

>
> * Make it possible to use RETURNING together with conditional DO INSTEAD
>   rules, such as for partitioning setups
>
>   http://archives.postgresql.org/pgsql-hackers/2007-09/msg00577.php

Heikki Linnakangas

Kris Jurka

Andrew Maclean

Brendan Jurd

Fix markup in previous commit.

Albe Laurenz

don't need to recommend nightly analyzes anymore unless autovacuum is off.

Backpatch to 8.2.X.

Oleg.

* adds a few missing words to some commands (like adding GIN as a valid
index type or OWNED BY for ALTER SEQUENCE,...)

* support for ALTER TABLE foo ENABLE/DISABLE REPLICA TRIGGER/RULE

* autocomplete CREATE DATABASE foo TEMPLATE (mostly done to prevent
conflicts with the TEMPLATE keyword for text search)

* support for ALTER/CREATE/DROP TEXT SEARCH as well as COMMENT ON TEXT
SEARCH and the corresponding psql backslash commands.
This proved a little more difficult than expected due to the fact that
words_after_create[] is used for two purposes - one is to provide a list
of words that follow immediatly after CREATE (or DROP) and the other
purpose is to use it for autocompleting anywhere in the statement if the
word in that struct is found with a query.
Since TEXT SEARCH CONFIGURATION|DICTIONARY|TEMPLATE|PARSER results in 3
words instead of one (as all the other words in that list are) I added a
flag to the struct to tell create_command_generator() to skip that entry
 for autocompleting immediatly after CREATE which feels like a dirty
hack (but that holds true for a lot of code in tab-complete.c).


Stefan Kaltenbrunner

of PostgreSQL 8.2) and provides a link to compiling and linking section.

Euler Taveira de Oliveira

Backpatch to 8.2.X.

the problems non-root reading /etc/shadow.

contrib/intarray's GIN opclass override the built-in default.  Per bug #3048
and other complaints.

Fujii Masao