以目标节点为导向的XML路径查询处理

XML查询语言将复杂路径表达式作为核心内容.为了加速路径表达式处理,基于路径分解和结构连接操作的处理策略需要更深入的研究.以目标节点为导向的XML路径查询处理框架被提了出来.该方法利用了扩展基本操作来减少连接操作的数目.在路径分解和查询计划选择的过程中,利用查询树中的目标节点来避免中间结果的传递.除了分解规则和策略以外,提出了一组扩展的基本操作和实现算法.初步的实验结果显示,该方法具有良好的性能.它为路径查询处理提供了更多的选择.

Target Node Aimed Path Expression Processing for XML Data

XML query languages take complex path expressions as their core. To facilitate path expression processing, the processing strategy based on path decomposition and structural join operation needs to be investigated more deeply. In this paper, a target node aimed at path expression processing framework for XML data is proposed. This approach makes use of the extended basic operations to reduce the number of join operations. In the procedure of path decomposition and query plan selection, target node in the query tree is utilized to avoid the transfer of the intermediate results. In addition to decomposition rules and strategies, a set of extended basic operations and implementation algorithms are proposed. Preliminary experiments indicate this approach has good performance. It provides path query processing with more choices.