I have been asked to come up with a scalable design for a new application that we have. This application has a java front end that will be running off of 4 clustered unix servers.

The back end will be Oracle 10.2.0.3. This will be a global application used by many countries. I was asked what the best design would be for the Oracle database.

We just completed a proof of concept with some US users. The database was around 30G when complete and I was told it has over 15,000 users. From the backend I did not see anything like that. Only in the hundreds. We had no issues with the single instance.

Can someone point me in the right direction of what questions I should be asking? I want to ensure I set this up right from the beginning so it is scalable to many countries and users. Should I have many databases or a couple broken down by timezone? Is there batch processing or small queries? What is the recovery requirements?

I am not that familiar with RAC yet. Is this something I should consider?