【摘要】 标准 SQL是一种基于关系数据模型的数据库查询语言 ,其中的 select语句基本不具备复杂类型数据查询能力 .因此 ,在设计多媒体数据支撑环境 E- Support时 ,针对其对象描述和查询方面的需求 ,提出一个面向对象数据模型 .在此基础上 ,给出一个基于面向对象数据模型的扩展 select语句的文法 .介绍其解释程序的实现技术 ,重点讨论复杂类型属性和对象引用属性的处理方法以及如何将查询结果封装成对象更多还原

【Abstract】 The standsrd SQL is an query language of data base based on relational data model, in which the select statement is not provided with the capability of quering data of complicated type in the main. In designing E support, namely, the supporting environment of multi media data, an object oriented data model is advanced to meet the need of object description and query; and then, the grammar of extended select statement based on object oriented data model is given; and finally, the technology for implementing its interpreter is presented. The discussion lays emphasis on the attribute of complicated type and the attribute of object reference as well as on how to pack the result of query into object.更多还原