Abstract: Processing overhead for maintenance of integrity of one or more de-normalized relational databases including an entity-attribute-relationship architecture during updates thereof in a decision support system is expedited by transfer and merger of data by use of standard utilities under control of control files corresponding to the database architecture. Complexity of maintenance of the database as the database architecture is changed is minimized by alteration of the control files but not the utilities or the complex protocols of previously known systems. By thus reducing processing overhead when updating and/or refreshing of the database(s) is to be done, data may be efficiently maintained with improved currency while enhancing availability of the system to the user.