基于树元组的XML文档中的多值依赖

XML模式设计是XML数据库设计的关键，同关系数据库相似，对引起XML数据更新异常的原因及消除更新异常的方法进行研究具有重要的意义。与Vincent等人不同，本文在DTD一级对XML文档中的多值依赖进行了研究。首先分析了XML文档模式设计的研究方法，其次，重新给出了XML树，树元组等的定义，消除了Arenas等人在定义模型“相等”上的二义性，并基于DTD提出了XML多值依赖的概念。最后，分析了XML中多值依赖的公理系统及蕴涵问题并指出了XML多值依赖未来的研究方向。

Multivalued dependency based on tree tuples in XML

XML schema design is the key of databases design. Similarly to the relational database, it is important to research onthe reasons that generate the update anomalies and methods which avoid update anomalies and redundancies. This paper has con-ducted the research to multivalued dependence in XML documents on the schema level that is quite different from Vincent et al..The method of schema design of XML documents is analysed. Tree tuple approach is improved and concepts of XML tree, treetuples and etc are given. Then based on DTD, the definition of multivalued dependencies inXML is proposed. The axiomatizationsand implications problems for XMVD are analysed and several other issues related to the ones addressed in this paper that warrantfurther investigation are proposed.