支持有序XML文档的动态编码  

Dynamic Labeling Scheme for Order-sensitive XML Data

作　　者：覃遵跃[1] 蔡国民[1] 郭鑫[1] 张彬连[1] 汤庸[2] 

机构地区：[1]吉首大学软件学院,湖南张家界427000 [2]华南师范大学计算机学院,广州510631

出　　处：《小型微型计算机系统》2015年第7期1464-1469,共6页Journal of Chinese Computer Systems

基　　金：国家"八六三"计划重大项目(2013AA01A212)资助;国家科技支撑计划项目(2012BAH27F05)资助;国家自然科学基金项目(61363073)资助

摘　　要：对有序XML文档树的节点进行编码是提高检索XML文档效率的基础技术,已经提出的路径编码和区间编码等方案能够有效支持查询,但在插入节点时存在二次编码节点多,更新效率低等问题.为了支持对有序XML文档的更新操作而提出了CDBS、ORDPATH、向量编码和素数编码等方案,但这些方案需要较大的存储空间,并且查询效率也较低.针对存在的这些问题,文章提出了新的编码方法 VUS,该方法采用国际通用的unicode字符集作为编码字符,在该编码方法的基础上设计了VUSPrefix和VUS-Region编码方案,并针对这些编码方案设计高效算法实现有序XM L文档的更新计算.多角度的实验结果显示,所提出的编码方案具有很好的更新性能,并且也没有牺牲查询性能,同时拥有较小的编码空间.The basic technology to improve the efficiency of retrieving XML data is to design labeling scheme for the nodes of Order-Sensitive XML tree,path and interval labeling schemes have been put forward, which can efficiently support queries. But there are theproblems of secondary coding nodes and updating of low efficiency when inserting new nodes for XML data by the proposed schemes.To support update operation on orderly XML data, CDBS, ORDPATH, vector labeling and prime labeling etc. have been presented-these schemes require a large labeling space. Meanwhile, the query efficiency is also low. For this problem, a novel labeling method-VUS （ Valid Unicode String ） is proposed, which uses an internationally accepted unicode character set as the coded character, then,VUS-Prefix and VUS-Region labeling schemes are structured on the basis of this method. Finally, designing efficient algorithm imple-ments update operation on orderly XML data. The conducted experimental results show that VUS efficiently processes update withsmaller labeling space and without sacrificing query performance.

关 键 词：有序XML树 VUS编码 更新 查询 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]