摘要
文章首先将XML数据查询定义为一个有序的带标记树而数据库是一个有序的带标记树集合,对于查询的回答是一个或几个从查询树结点到数据库结点的同态映射;其次,对一般意义下的XML树模型进行了形式化改造,并且基于改造后的XML树模型构造了查询;最后,阐述了这一工作的意义。
The paper proposes some notions on XML documents and XML query. Then it formalizes the notions. These notions are ordered trees with labels for XML documents, a set of the trees for XML database and that answers for an XML query are homomorphism from query tree nodes to database nodes. In the end of the paper the significance of the work is explained.
