Standard Relational and Network Database Languages

For any type of software to become standard, whether a third generation language or an integrated project support environment (IPSE), it must undergo a series of modifications and updates which are a direct result of theoretical and empirical knowledge gained in the process. The database approach to the design of general purpose infonn­ ation systems has undergone a series of revisions during the last twenty years which have established it as a winner in many different spheres of infonnatio...