一种改进的建立XML数据的路径索引的方法

随着XML日益普遍的应用,如何快速准确地访问XML文档中的数据已成为亟待解决的关键问题,建立路径索引是提高查询效率的一种重要手段.本文分析了可能导致路径索引复杂度过大的原因,提出一种分步建立和更新路径索引的方法,对于具有复杂引用关系的源数据,根据查询的需要只对数据中部分路径建立索引,并通过阈值控制索引的规模.实验结果表明,本文提出的方法可以有效地降低建立和维护XML数据的路径索引的代价.

An Improved Method for Creating Path Indices for XML Data

With widespread application of XML for exchanging and expressing data on the Web, efficient access to XML data has become a key problem need to be solved. Building path index is one of important means to enhance query efficiency. In this paper, the authors study the reason that may results in large complexity of path indices. They put forward a method for creating and updating path indices of XML data step by step. For data with complicated reference relationships, path index is built for only part of the data according to query necessity. Threshold is used to control scale of a path index. Experiments indicate that method suggested in this paper can effectively reduce cost for creating and maintaining path indices of XML data.