【摘要】 针对面向对象XML数据的两种存储模式:集中式和分布式,基于两种存储模式的存储结构信息的路径仓和存储XML数据的数据仓,分别设计并实现了面向对象XML的查询代数.采用支持继承的扩展XML-RL查询语言,使用多态元素、多态引用、独占元素和独占引用四种典型查询,分析了两种存储模式的性能.结果表明查询多态元素和独占元素时,集中式优于分布式,而查询多态引用和独占引用时分布式优于集中式.更多还原

【Abstract】 Aiming at the two storage models for object-oriented XML data,i.e.,centralized and decentralized,the query algebra for object-oriented XML is designed and implemented on the bases of their respective path repositories of XML structure information and data repositories of XML data.Introducing extended XML-RL query language to support inheritance,the storability of two models is analyzed by four typical queries: polymorphic element,polymorphic reference,monomorphic element and monomorphic reference.The result indicates that the centralized storage model outperforms the decentralized one at polymorphic element and monomorphic element queries and vice at polymorphic reference and monomorphic reference queries.更多还原