Maintaining data used for performing "what-if" analysis is disclosed. The systems and methods of the invention define an efficient mechanism allowing a user to specify how base values from a database are to be changed. The changes can be held in a local delta cache which is only exposed to a single user, leaving the base data unchanged. The changes can also be maintained in a write-back partition, which results in the changes being exposed to all clients of the database. Values in the write-back partition can be selectively rolled back if required.