XML强闭包依赖的研究

Research on XML Strong Inclusion Dependency

XML闭包依赖是基本的完整性约束。当XML文档出现不完全信息时,XML闭包依赖同样对于阻止XML数据的更新异常、查询优化以及索引设计具有重要的意义。提出了在不完全信息环境下基于一致路径集合的XML强函数依赖和XML强闭包依赖的定义,研究了XML强闭包依赖的判定定理。在提出XML强闭包依赖推理规则的基础上,对其有效性和完备性进行了证明。最后分析了XML强闭包依赖和XML强函数依赖的关系。

XML inclusion dependency is essential integrity constraints. When XML documents come forth incomplete information, XML inclusion dependency has also important meaning for updating anomaly prevention, query optimization and index design in XML document. XML strong functional dependency＇ definition and XML strong inclusion dependency＇ definition based on consistent path set under the incomplete information circumstances were formalized,jud- ging theorem for XML strong inclusion dependency was studied. Based on formalizing inference rules of XML strong inclusion dependency, the soundness and completeness of inference rules were proved. At last the relation of XML strong functional dependency and XML strong inclusion dependency was analysed.