I am developing a J2EE application and most of it is already developed using MySQL but there has been demand that we are not sure on which "database system" will our application deploye i.e the application is to be distribiute to number of clients and some will be using mySql/oracle.

What can be best solution to overcome it.

What i was thinking is to bound all database in Descriptors ... but i am unable to do it. i want that i specify the tables using the entity beans, thier relationships using descriptor and when i deploy the application it automatically creates these tables in the DB. but how ??? is it possible?

2: if the above task is possible then how come my beans know which database system and which database in that system to be use??

Please help me out as soon as possible.