面向原生XML数据库的自适应路径索引  

Adaptive Path Index for Native XML Databases

作　　者：邓泽[1] 曹海峰[1] 冯丹[1] 周可[1] 施展[1] 

机构地区：[1]华中科技大学计算机学院,湖北武汉430074

出　　处：《小型微型计算机系统》2009年第9期1748-1751,共4页Journal of Chinese Computer Systems

基　　金：国家"九七三"重点基础研究发展计划项目(2004CB318201)资助;中国下一代互联网应用示范项目(CNGI-04-5-1D)资助

摘　　要：路径索引是改善原生XML数据库(NXD)性能的一项重要技术.然而现有NXD中的路径索引缺乏动态性、自适应性,妨碍了NXD的查询性能改善.本文根据Chung C等提出的面向XML数据的自适应路径索引(APEX)[1],结合NXD的特点,提出面向NXD的自适应路径索引(NXD-APEX).NXD-APEX继承了APEX自适应性,并通过加入时间特征到APEX的常用路径挖掘算法中,使NXD-APEX能有效处理具有时间局部性的查询.同时针对NXD-APEX可能导致的大空间开销问题,提出一种基于收益的索引筛选算法.试验表明:NXD-APEX能以合理的空间开销有效地改善NXD的查询性能.For native XML databases （ NXD）, path index is one important way to improve query performance. However, main stream native XML databases just index paths in static ways, which lacks the adaptive feature to go against the speed improvement of dynamic queries. In this paper, based on APEX and the common features of NXD, an adaptive path index for NXD （NXD-APEX） is proposed. Unlike APEX, NXD-APEX can speed up the queries of temporal locality by integrating temporal feature into frequently-used paths extracting algorithm. Meanwhile, NXD-APEX can greatly reduce its space cost under slight performance degradation, using a novel gain-based filtering algorithm. Experiments show that NXD-APEX can effectively improve the query performance of NXD at a reasonable space cost.

关 键 词：原生XML数据库 自适应路径索引 常用路径挖掘算法 索引筛选算法 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]