Обсуждение: jdbc 8.n driver / pgcluster problem

-- 
Christian Dannemann
Managing Director
Merus Software Ltd
Phone: +44 (0)1453 708 600
DDI: +44 (0)1453 708 610
VoIP: christian@sip.merus.co.uk
http://www.merus.co.uk

On Wed, 20 Sep 2006, Christian Dannemann wrote:

> Apparently, pgcluster's replication only works when using jdbc driver < 8.0,
> so 7.4 works fine and all database changes submitted to one database are
> replicated across the cluster without any problem.
>

The 8.0 driver started making full use of the V3 query protocol and since
pgcluster uses query based replication I'd bet it doesn't correctly handle
queries submitted via the extended query protocol.  If this is true that's
a very serious flaw and affects all other clients (that use the extended
query protocol), not just a JDBC issue.  A workaround for the JDBC driver
might be adding ?protocolVersion=2 to your URL, but this revelation would
make me hesitate to use pgcluster at all.

Kris Jurka

Christian Dannemann wrote:
> To whom it may concern:
>
> We have installed pgcluster (1.3 with postgres 8.0.1) and are currently
> testing it as we want to use it for a client in a production environment.
>
> Apparently, pgcluster's replication only works when using jdbc driver <
> 8.0, so 7.4 works fine and all database changes submitted to one
> database are replicated across the cluster without any problem.
>
> When we use the 8.0 driver, the changes only go to the database that we
> connect to and are not replicated to the cluster.
>
> I was wondering if this problem is known and if yes, if there is a plan
> to fix it (either in the jdbc driver or in pgcluster).

The main change between the 7.4 and 8.0 drivers was a change to use the
extended query protocol instead of the simple query protocol. Perhaps
pgcluster does not support the extended query protocol correctly?

-O