摘要
为了提高XML数据库查询引擎中核心的Twig查询处理效率,提出基于语义信息的Twig查询处理TwigRT算法.该算法根据XML模式定义中的对象语义信息识别XML数据中的对象,将其属性和值存储在关系数据库表中;Twig查询分解为内容查询和结构查询两部分,其中内容查询部分通过SQL在数据库表中的查询实现,起到缩减结构查询范围的作用;结构查询部分通过整体结构匹配算法实现.最后通过实验验证了算法的有效性.
An algorithm TwigRT is proposed to improve the efficiency of twig query processing in XML database.TwigRT can store an object′s properties and their value into relational tables according to the semantics defined in XML schema.Twig query is decomposed into content query and structure query,then content query is processed by execute SQL on relational tables,and structure query search scope is reduced by previous step results and can be processed using holistic join algorithm.The experimental results show that our approach is scalable and efficient on this problem.
引文
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