摘要
STEP标准数据存取界面—— SDAI为应用程序提供了独立于数据存储的 STEP数据访问界面 .SDAI允许访问不同的数据存储系统 ,有不同的实现语言联编方式 ,如果对每一种实现语言和数据存储系统单独实现SDAI,其工作量将是巨大的 .该文选择关系数据库作为 SDAI数据存储系统 ,C语言作为实现语言 ,实现系统独立于不同的关系数据库系统 ,并且为不同语言的联编提供了一个统一的开发平台 ,提高了系统的开放性和可扩展性 ,为 STEP在企业信息集成中的应用提供了核心操作 .STEP建模语言 EXPRESS、关系数据库、SDAI实现语言在模式表示上的不匹配是系统实现要解决的主要问题 .该文从数据字典。
Standard Data Access Interface (SDAI) in STEP isolates the application program from the underlying data storage system. SDAI contains a functional definition part and several specific programming language bindings. This paper describes an architecture to implement SDAI late binding on relational database systems. The architecture has a database layer to make it portable among various relational database systems, a core STEP object operation layer to provide reusable modules for different implementation languages, a data dictionary to facilitate late binding, and finally, the standard data access interface which will be called by application programs. The interfaces between these layers are identified. To store STEP data in relational database systems,the translation of EXPRESS data models to relational data models is also discussed. To distinguish between SDAI data schemas and application data schemas, SDAI data schemas such as session schema in the SDAI layer and application data schema in the core STEP objects operations layer are managed. The SDAI C late binding on Oracle based on the architecture have been implemented and the other SDAI language bindings on the architecture with relatively lower implementation cost will be implemented.
出处
《计算机学报》
EI
CSCD
北大核心
2002年第3期254-261,共8页
Chinese Journal of Computers
基金
国家"8 63"/CIMS主题项目 (2 0 0 1AA415 2 2 0 )资助
