In this ESPRIT research report of a group of engineers in the CAD*I project the possibility of using a database management system (DBMS) for computer aided design (CAD) purposes is analyzed and conditions are derived that enable CAD systems to manage CAD models containing increasing amounts of data and more and more intelligent relations. Today CAD models constitute isolated islands of data stored in independent files, and to create and maintain relations between pieces of information stored in several models (files) in a multi-user environment is a complex task. At a conceptual level, a relational DBMS associated with the language SQL (ISO standard) is the ideal tool to create and maintain such relations. At the implementation level, it is of the highest importance to define the optimum granularity of information to be stored in the database in order to get a good response time from such a system.weiterlesen