【摘要】 XML是用于数据表示、交换的Internet标准。通过和DTD的连接可以用像XML QL这样的语言来执行丰富的查询操作。近年来 ,很多人致力于半结构化数据模型和其查询语言的研究[1,2 ,5] ,其重点逐渐转移到XML数据集的查询上来 ,其中两个重要问题是使XML查询语言正规化和如何将XML数据转换为底层存储格式以获得理想的效率[4 ] 。表述了一个XML的正规数据模型及其代数方法 ,并介绍基于RDBMS实现该模型的方法更多还原

【Abstract】 Extensible Markup Language(XML) is a Internet standard for data representation and data exchange. We can do various queries on XML using query languages such as XML QL when it has been bound to DTD (Document Type Definition) .A lots of people have made great efforts on the research of modeling semi structure data and its query languages , and recently these efforts have shifted toward modeling XML data and querying XML datasets. There are two important question that how to formalize XML query language and how to choose the strategies for storing XML data in underlying storage representation to archive efficiency . This paper represents a formal data model and its algebra functions. We describe our implement based on RDBMS also.更多还原