Re: Replication Documentation

Thanks for mentioning about pgpool!

> <sect2><title> pgpool </title>
>
> <para> <application>pgpool</application> was initially created by
> Tatsuo Isshii as a portable alternative to Java connection pool
> modules. He subsequently observed that it wouldn't take very much
> effort to extend it to create a simple replication system: if it
> is forwarding SQL queries to a PostgreSQL instance, extending that
> to two databases is very straightforward. </para>
>
> <para> It suffers, by nature, from the problems associated with
> replicating using capture of SQL statements; any sort of
> nondeterminism in the replicated statements will cause the
> databases to diverge. </para>
>
> <para> On the other hand, it is very easy to install and
> configure; for users with simple requirements, that can
> suffice. </para>
>
> <para> A <application>pgpool-2</application> is under way which
> introduces a more sophisticated query parser to try to address the
> nondeterminism issues; that may limit ongoing support for the
> legacy version.</para>

pgpool-II (not pgpool-2, please) does not try to resolve
nondeterminism issues but try to add parallel SELECT query
execution. Also we will continue to support legacy version until
pgpool-II becomes stable enough.

Also you might want to add pgpool development site URL.

FYI, pgpool-II presentation material for PostgreSQL Anniversary Summit
can be obtained from:
http://www.sraoss.co.jp/event_seminar/2006/pgpool_feat_and_devel.pdf
--
Tatsuo Ishii
SRA OSS, Inc. Japan