【摘要】 论述了应用图形数据库的概念来组织和管理图形数据。图形数据库是一种面相对象的工程数据库管理系统,是工程数据库在图形设计领域的应用。引入了图形数据库查询语言GDQL(GraphicDatabaseQueryLanguage)。GDQL是以对象数据管理组织(ObjectDataManagementGroup,简称ODMG)组织的对象查询语言(ObjectQueryLanguage,简称OQL)标准为蓝本,采用类SQL形式,专用于图形数据库的查询语言。介绍了面向对象图形数据库的一般查询方法、图形数据库的查询处理器结构、GDQL的语言描述以及查询优化等内容。更多还原

【Abstract】 This paper introduces the concept of graphic database for the organization and management of graphic data. Graphic Database is object-oriented Engineering database management system, and applied to graphic design. Query language GDQL(Graphic Database Query Language) is introduced to graphic database. GDQL, based on ODMGs OQL criteria and the form of SQL-like, is specialized to graphic database. It is emphasized that the query plan of object-oriented graphic database, query controller structure of graphic database, language specification of GDQL and query optimization.更多还原