BSC:一种高效的动态XML树编码方案

BSC:An Efficient Numbering Scheme for Dynamic XML Trees

确定一篇XML文档中任意两个节点之间是否存在某种结构关系,是XML查询处理过程的一个重要组成部分。XML树编码方案为每个节点分配唯一编号,仅通过比较节点编号而不必访问原XML文档,就可以快速有效地确定节点间的结构关系。随着XML应用不断普及,能否高效地支持更新操作,已成为XML树编码方案研究的一个重要课题。本文基于二进制小数的特性,提出了一种新的XML树编码方案——BSC,它可以完全高效地支持XML更新操作而不需要重新编码。实验结果证明,与已有的动态编码方案相比,BSC编码无论在静态编码方面还是在动态更新方面都具有很好的性能。

It is very important to detect whether there are structural relationships between two nodes in XML queries. The numbering scheme is designed to label the XML nodes so that the structural relationships between nodes can be easily determined by comparing their labels without accessing the original XML file. With the increasing popularity and application of XML related standards, it is urgent to find a numbering scheme that is able to support XML data up- dates. This paper presents a novel XML tree numbering scheme, called BSC, which takes advantage of the property of binary decimal numbers and can completely avoid re-labeling any existing nodes when the XML update is performed in any case. Our experimental results show that BSC works much better than the existing dynamic numbering schemes considering either the static numbering or the XML data updates.