一种具有多模态索引结构的XML查询算法

An XML Query Algorithm with Multi-modal Index Structure

将编码方案、路径索引和名字外延思想相结合,提出一种针对XML数据检索的多模态索引结构.它既可支持结构连接计算,用以判断任意结点之间的子孙后代关系,也可支持基于名字外延的路径连接算法,用以判断任意结点之间的父子关系,同时可支持包含拥有关系的小枝查询;进而给出基于该结构的外延连接算法,使得对于长度为n的Xpath绝对路径查询,最多只需n/2-1次外延连接.实验结果表明,本文提出的索引结构可有效提高查询处理性能.

This paper proposes a multi-modal index structure to retrieve XML data based on the idea of the numbering scheme, the path index and name extension. The index structure not only determines ancestor/descendant relationships by supporting the structural join algorithm but also determines parent/child relationships by the path join algorithm based on name extension, and meanwhile effectively deals with branching query including holding relationships. Then, an extension join algorithm based on the index structure is given so that n/2-1 times at most for joining among extensions are needed for Xpath absolute path queries with n query nodes. Experimental results show that the new index structure can effectively enhance the query performance for XML data.