Research On Object-oriented Engineering Database Technology Incorporated Into CAD

With the development of engineering database incorporated into CAD, the use ofengineering database to manage CAD geometry data is put in a more important place.With the development of object-oriented database, it is a tendency that the object-orienteddatabase becomes the base to implement engineering database system. By analyzing the history and the development of engineering database and theobject-oriented technology incorporated into engineering database, the architecture ofobject-oriented engineering database is given. To build a pure object-oriented databasesystem, the architecture of object-oriented database and the object data structure weredefined. A reference type of object data was used to solve the relations between persistentobject data. The B-rep model was used to describe the CAD geometry object data. Theobject data definition, addition, deletion and modification for basic data managementwere also implemented. Keyword index, object traversal, and finding by relation methodto query object data are used in object-oriented engineering data management. Based onthe generic object-oriented database system GOODS, 0-3 dimensional CAD geometrydata structure with data operations are implemented in C++.