Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Re: Oracle 9i RAC JDBC listener connection load balancing

Re: Oracle 9i RAC JDBC listener connection load balancing

From: Joe Weinstein <joeNOSPAM_at_bea.com>
Date: Fri, 14 May 2004 08:47:54 -0700
Message-ID: <40A4EA2A.1000404@bea.com>

Matt wrote:

> As far as I know TAF doesn't support thin JDBC connections....

Hi Matt. As of the latest 10g driver, the thin driver will take info about the alternate RAC instances to connect to, via the URL, and will try the reconnect. However, the fundamental problem of replicating/reconstituting the transactional *and computational* context of a sophisticated java client (re-used Prepared statements that require package state, XA transactions etc) is not sustained by the DBMS failover, so for JDBC, the failover is anything but transparent. The only safe response is to roll back any externally moderated transaction, and return all the way to the creation of the statements, which is the moral equivalent of reconnecting. In fact, for any system that caches prepared statements (and this may include the 10g driver itself!), it is probably safest to manually reconnect anyway...

Joe Weinstein at BEA

> 

>>Oracle Net comes with Transparent Application Failover and Load
>>balancing, suitable for RAC. Exactly what you need!
>>Please read those manuals prior to resorting to your own 'solution'
>>(which won't be supported by Oracle)
Received on Fri May 14 2004 - 10:47:54 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US