1. A method for enabling users to model changes to entities in large scale sets of data in different respective sandbox caches comprising: loading sets of data in a database; organizing the loaded data in entity caches according to an entity model, each entity cache corresponding to one or more entities; creating an initial report of information drawn from the loaded data for manipulation by a user through a user-interface; storing information in the initial report in a respective sandbox cache having data organized according to the entity model; and enabling the user to manipulate the respective sandbox cache to change values in the data organized according, to the entity model in the respective sandbox cache without necessarily changing values of corresponding data organized according to the entity model in other sandbox caches or in the database.