消除XML亚强多值依赖引起冗余的一种分解方法  

A decomposition method of eliminating redundant caused by XML inferior strong MVD

作　　者：殷丽凤[1] 金宇 邱占芝[1] 

机构地区：[1]大连交通大学软件学院,辽宁大连116028 [2]大连装备制造职业技术学院,辽宁大连116110

出　　处：《电子设计工程》2014年第4期5-8,共4页Electronic Design Engineering

基　　金：国家自然科学基金项目(61074029);辽宁省自然科学基金项目(20102014)

摘　　要：数据约束是数据库规范化理论的基础,不完全信息引入XML文档后,需要重新定义数据约束。本文基于子树信息等价和子树信息相容的概念给出了XML亚强多值依赖的定义;提出了弱键路径和XML亚强多值依赖弱范式的定义,通过实例分析XML亚强多值依赖引起数据冗余的原因,提出分解不完全XML文档满足XML亚强多值依赖弱范式的定理。研究成果可较好的处理不完全XML文档中存在XML亚强多值依赖引起的数据冗余问题,避免了数据冗余所带来的操作异常。Data constraints are the basis of the database normalization,the introduction of XML documents with incomplete information,data constraints need to be re-defined.Based on the equivalence of the sub-tree information and the consistent of the sub-tree information,XML inferior strong multi-valued dependencies＇ definition was given.Weak keys and XML inferior strong multi-valued dependencies weak normal form were given.The reasons of data redundancies aroused by XML inferior strong multi-valued dependencies in incomplete XML document via the instance were analyzed,the theorem of decomposition for incomplete XML document for meeting XML inferior strong multi-valued dependency were presented.The production in this work can deal with data redundancies aroused by XML inferior strong multi-valued dependencies in incomplete XML document and avoid abnormal operation.

关 键 词：不完全信息 子树信息等价 子树信息相容 XML亚强多值依赖 XML亚强多值依赖弱范式 

分 类 号：TP311.13[自动化与计算机技术—计算机软件与理论]