关键词: 关系模式, 函数依赖, 轴节点, relation mode, functional dependency

Abstract: DTD does not support the definition of the complex elements. Based on the formal definition of XML schema, the complex elements and the functional dependence were defined in XML. A new mapping method based on pivot node was proposed; it obtained the relation tables according to the pivot node and the XML functional dependences. The constraints that were represented by the XML functional dependences, as well as the content and the structure, were preserved at the same time. Much storage redundancy can be reduced. Furthermore, the relations mapped from XML were proved in Third Normal Form (3NF)．

Key words: pivot node