Re: Distributed transactions and Oracle RAC load balancing problems - advice needed!

Eirik Tryggeseth wrote:

> During deployment of an application using distributed transactions managed
> under COM+ on an Oracle 9i RAC database, we encounter situations where the
> load balancing mechanisms in the RAC result in that the component context in
> the distributed transaction (in our case two different COM components)
> cannot hold onto the same ODBC connection. Or it may be that the database
> session is changed dynamically for the ODBC connection, so that component 2
> in the transaction cannot read updates made by component 1 in the
> transaction.
>
> Originally we use MS ODBC driver for Oracle (2.573.9030.00) , and Oracle XA
> (9.2.0.1.0). We have investigated Oracle's ODBC driver (9.02.00) ,
> EasySoft's ODBC driver and DataDirect's ODBC driver to find if any of these
> can ensure that the same session is held for the connection during the
> entire lifetime of the transaction. It seems that BEA with WebLogic has
> solved the solution with their JDBC connection pool configuration (parameter
> KeepXAConnTillTXComplete).
>
> Has anyone else run into this problem and found a solution or work-around?
> According to Oracle's promo documents no application changes should be
> needed for using the RAC option.
>
> Br,
>
> Eirik

ODBC is a really bad idea if you want any capability more sophisticated than a slow, insecure, connection. Also you should upgrade to 9.2.0.5.

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace 'x' with 'u' to respond)