== PostgreSQL Weekly News - November 19 2006 ==

== PostgreSQL Weekly News - November 19 2006 ==

== PostgreSQL Product News ==

Slony-I 1.2.1, 1.1.6 released.
http://pgfoundry.org/frs/?group_id=1000122

pgEdit 1.2 beta released.
http://pgedit.com/beta/pgedit

OpenMFG Releases Version 2.0 released.
http://www.openmfg.com/

== PostgreSQL Jobs for November ==

http://archives.postgresql.org/pgsql-jobs/2006-11/threads.php

== PostgreSQL Local ==

Everything this week was global.

== PostgreSQL in the News ==

PostgreSQL swept the RDBMS category in Linux Journal's Editor's Choice 2006
http://www.linuxjournal.com/article/9368

Planet PostgreSQL: http://www.planetpostgresql.org/

General Bits, Archives and occasional new articles:
http://www.varlena.com/GeneralBits/

PostgreSQL Weekly News is brought to you this week by David Fetter,
Dave Page and Robert Treat

== Applied Patches ==

Tom Lane committed:

- When truncating a relation in-place (eg during VACUUM), do not try
to unlink any no-longer-needed segments; just truncate them to zero
bytes and leave the files in place for possible future re-use. This
avoids problems when the segments are re-used due to relation growth
shortly after truncation. Before, the bgwriter, and possibly other
backends, could still be holding open file references to the old
segment files, and would write dirty blocks into those files where
they'd disappear from the view of other processes. Back-patch as
far as 8.0.

- Repair problems with hash indexes that span multiple segments: the
hash code's preference for filling pages out-of-order tends to
confuse the sanity checks in md.c, as per report from Balazs Nagy in
bug #2737. The fix is to ensure that the smgr-level code always has
the same idea of the logical EOF as the hash index code does, by
using ReadBuffer(P_NEW) where we are adding a single page to the end
of the index, and using smgrextend() to reserve a large batch of
pages when creating a new splitpoint. The patch is a bit ugly
because it avoids making any changes in md.c, which seems the most
prudent approach for a backpatchable beta-period fix. After 8.3
development opens, I'll take a look at a cleaner but more invasive
patch, in particular getting rid of the now unnecessary hack to
allow reading beyond EOF in mdread(). Backpatch as far as 7.4. The
bug likely exists in 7.3 as well, but because of the magnitude of
the 7.3-to-7.4 changes in hash, the later-version patch doesn't even
begin to apply. Given the other known bugs in the 7.3-era hash
code, it does not seem worth trying to develop a separate patch for
7.3.

- Clarify description of CIDR-address column of pg_hba.conf, to
discourage people from trying notations like '10.6/16', which is
accepted but does not mean what you probably think. Per example
from Paul Forgey.

- Repair two related errors in heap_lock_tuple: it was failing to
recognize cases where we already hold the desired lock "indirectly",
either via membership in a MultiXact or because the lock was
originally taken by a different subtransaction of the current
transaction. These cases must be accounted for to avoid needless
deadlocks and/or inappropriate replacement of an exclusive lock with
a shared lock. Per report from Clarence Gardner and subsequent
investigation.

Andrew Dunstan committed:

- Force plperl and plperlu to run in separate interpreters. Create an
error on an attempt to create the second interpreter if this is not
supported by the perl installation. Per recent -hackers discussion.

Bruce Momjian committed:

- Rename replication section "High Availability and Load Balancing".

- In failover docs, data Partitioning documentation section reduced
and moved to the end.

- In failover docs, use more standard terms for replication, ideas
from Markus Schiltknecht.

- In failover docs, mention two-phase commit for having all
transactions commit on all servers.

- In failover docs, reconfigure failover/replication doc items to be
varlist entries, rather than new sections, so they appear all on the
same web page.

- In failover docs, clarify replication items, and define some terms.

- Improve broadcast wording for failover/clustering documentation.

- Add URL for case identifiers to TODO list.

- Fix xrefs for failover changes.

- Update failover docs, per suggestions from Chris Browne.

- In developer FAQ, fix URL for patch hold queue.

Peter Eisentraut committed:

- Small message equalization fix

- String fix in pgsql/src/backend/access/transam/xlog.c

- Message fix in pgsql/src/backend/catalog/aclchk.c

Neil Conway committed:

- Fix a typo.

- Remove a bunch of antique information from the appendix in the docs
that discusses CVS. Remove the recommendation to use cvs 1.10.
Remove discussion of alleged CVSup binaries on postgresql.org,
because they have not existed for several years. Remove discussion
of how to build cvsup from source because the existing text is
outdated, and more accurate information is available from the CVSup
homepage.

Michael Meskes committed:

- Fixed small typo, missing 'l' in 'Cluserting' [sic]. Typo only in
commit message. ;)

== Rejected Patches (for now) ==

No one was disappointed this week :-)

== Pending Patches ==

Pavan Deolasee sent in a patch implementing HOT tables per last week's
discussion.

Markus Schiltknecht sent in a documentation patch with some
improvements to the replication documentation.

Simon Riggs sent in a patch which rearranges the 'caveats' section of
the table partitioning documents.

Tom Lane sent in a patch meant to address the xact-vs-multixact bugs
discussed at
http://archives.postgresql.org/pgsql-hackers/2006-11/msg00357.php

Gleb Kouzmenko sent in a patch which lets a client authenticate by
verifying its SSL certificate.

Robert Treat sent in a documentation patch which adds a section for
PLs not packaged with the core distribution and cleans up some URL
links along the way. Edits by Neil Conway.

Neil Conway sent in a patch which adds a column to pg_stat_activity
containing the time at which the backend's current transaction began,
or NULL if the backend is not inside a transaction. This is useful
for finding long-running transactions, and this information is not
otherwise easily available from outside the backend's session, at
least not without setting up a mechanism to query the system's process
table.