1. A computer-implemented method for a system upgrade of a database application system, the method comprising: establishing, by one or more data processors, a failover framework within a database in the database application system, the failover framework comprising of a plurality of database tables that are aliases of unmodified database tables of an original database application framework within the database; and enabling, by the one or more data processors and via one or more application servers, end-user read and write access to the database tables that are aliases of the unmodified database tables during the system upgrade.