I have an Oracle database driven web application running on JBOSS AP. It has its own database. This applicaiton requires to fetch/update few tables in Oracle ERP database. Some of the data that need to be updated has to be in real time and some data can be updated in batch mode on weekly basis. One approach to fetch/update the data in Oracle ERP is via DB links, but this approach is not feasible for our application for number of reasons for e.g. what will happen when the Oracle ERP database is down. I am trying to find what's the best way for my web applcation to be able to fetch data from Oracle ERP and also update the data in Oracle ERP? I would like to initiate the discussion at this forum and I'm sure it is going to be a long and interesting discussion.