首页 | 本学科首页   官方微博 | 高级检索  
     

基于扩展路径表达式的XML查询
引用本文:胡勤友,胡运发.基于扩展路径表达式的XML查询[J].计算机研究与发展,2003,40(5):720-727.
作者姓名:胡勤友  胡运发
作者单位:1. 复旦大学计算机与信息技术系,上海,200433;上海海运学院商船学院,上海,200135
2. 复旦大学计算机与信息技术系,上海,200433
基金项目:国家“八六三”高技术研究发展计划 (2 0 0 1AA115 0 2 0 )
摘    要:XML查询问题是当前计算机界研究的热点问题之一,国内外学者提出了众多的模型与算法.其中,日本学者Makoto Murata等提出采用扩展路径表达式来表达查询,并利用hedge自动机和字符串自动机进行XML的查询计算.这种方法与采用路径表达式控制的XML查询相比,克服了后者不能充分利用XML文档有序性的缺点.另外,扩展路径表达式具有较强的表达能力,可以表达任何MSO(一元二阶逻辑)查询.因此,扩展路径表达式已作为XML查询问题研究的主要理论框架之一,但是扩展路径表达式的编写比较困难,表达式也比较复杂,导致算法时间复杂度的提高.在扩展路径表达式中引入通配符,使得扩展路径表达式更加简单灵活;同时在查询的计算过程中提出并应用带截止集的自动机提高计算的时间效率.

关 键 词:XML查询  扩展路径表达式  通配符  带截止集自动机

XML Querying Based on Extended Path Expressions
HU Qin You , and HU Yun Fa.XML Querying Based on Extended Path Expressions[J].Journal of Computer Research and Development,2003,40(5):720-727.
Authors:HU Qin You  and HU Yun Fa
Affiliation:HU Qin You 1,2 and HU Yun Fa 1 1
Abstract:XML querying is being actively studied and several models and algorithms have been put forward Makoto Murata put forward a XML query language based on extended path expressions, and also advanced an algorithm for query computation based on hedge automata and string automata Extended path expressions have the advantage over path expressions in that they make full use of the orderliness of XML documents Moreover, extended path expressions are more expressive than the path expressions and can express any query as MSO can do So extended path expressions have been a major theory framework for the study of XML querying Extended path expression, however, are too complex to program in most cases, which leads to higher time complexity of the algorithm Extended path expressions are made simpler and more flexible by introducing wildcard into them, and the time complexity of the algorithm is also reduced by putting forward a new kind of automata, namely automata with a stop set
Keywords:XML querying  extended path expressions  wildcard  automata with a stop set  
本文献已被 CNKI 维普 万方数据 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号