分布式环境下的关系型XML查询优化

摘要

XML data query is one of the most important techniques in XML correlated techniques. Unlike regular XML query methods,relational-style XML query does not demand path expressions, which is very convenient to the query users. However, it brings on the problem of computation cost increase at the same time. To solve it,this paper gives a solution based on partial evaluation in distributed environment,and presents an optimized algorithm. Experiment shows that the algorithm can improve the efficiency of relational-style XML query and the adaptability to the query, with which the query can be made in more rigorous conditions.%XML数据查询是XML相关技术中一项的重要技术.与普通的XML查询方法不同,关系型XML查询不需要路径表达式,给查询者带来了便利,然而与此同时也带来了计算量增大的问题.针对该问题,给出了一种在分布式环境下基于部分求值的解决方案,并提出了优化算法.实验表明,该算法不仅能提高关系型XML查询的效率,而且能提高查询的适应性,使得查询可以在更为苛刻的条件下进行.