For Cad / Cam Engineering Database Management System Developed

Engineering database management system(EDBMS)is the key technique torealize CAD/CAM systems integration。In this paper,the theories and realizingtechnique to build an object－oriented engineering database management system(OODBMS)suitable for the mechanical CAD/CAM field are discussed in detail。 Firstly object－oriented data model(OODM)is built,the object relation andoperation are described formally。Then the theoretical foundation of the total systemhas been constructed。Afterwards,the function composition of the system isanalyzed and its total structure is formed。The implement technique of each part isstudied in detail,the major work is concerned on the principles and methods torealize object identification,the disposing principles and arithmetic of databasemode dynamically,method dynamic binding and call mechanism,constraintmechanism realizing,object query model building and object structure querylanguage(OSQL)realizing。Finally,the storage structure to realize object storage,storage and access tactics of clustering,hash and index are dealed with。Throughdouble buffer mechanism,the effective management of memory object is carriedout。...