A database management system is disclosed. One example provides request handler modules through which users interface with the database management system. A master control module assigns database servers to databases. A request handler module receives a database request from a client and sends a database identifier to the master control module, which determines an assigned database server and returns its location to the request handler module. The request handler module then sends the database request to the assigned database server, which handles the database request. The database management system facilitates the addition of database servers without requiring substantial system reconfiguration. It also facilitates migration of database assignments for improved efficiency or other reasons.