一种基于结构特征的XML数据查询方法

针对XML数据特有的树型结构模式，提出了一种将树型结构的XML数据和查询语句转化为特定格式的字符串，基于串匹配原理对结构复杂的XML数据进行查询的方法，避免了传统的基于路径的查询方式所必需的路径之间的连接（join）操作，从而提高查询效率。利用本文提出的编码方式，可以建立关于XML数据结构和数据内容舍为一体的索引。实验显示，本文使用的针对XML数据查询的方法比传统的基于连接操作的数据查询方式高效，且本方法具有良好的扩展性。

A Structure-encoded Method for Searching XML Datas

Aiming at the special tree-structure of XML data, we propose a novel structure-encoded method for searching XML documents. By representing both XML documents and XML queries in structure-encoded sequences, we show that querying XML data is equivalent to finding subsequence matches. Unlike index methods that disassemble a query into multiple sub-queries, and then join the results of these sub-queries to provide the final answers. Our structure-encoded method uses tree structures as the basic unit of query to avoid expensive join operations. The proposed method also provides a unified index on both content and structure of the XML documents; hence it has a performance advantage over methods indexing either just content or structure. Experiments show that the proposed method is effective, scalable, and efficient in supporting structural queries.