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    有内部冲突的F的广义左、右部冲突判定算法

    A Generalized Left-Hand Side and Right-Hand Side Conflicts Decision Algorithm of F with Inside Conflicts

    • 摘要: 数据库数据组织的无环性是数据库理论和应用中一个重要特性 如何把数据库模式分解成无环性是一个比较复杂的问题 ,特别是在FD集F有内部冲突时无α环的分解问题 为了解决这一问题 ,讨论了有内部冲突的FD集F有广义左部冲突或广义右部冲突时和对称左部属性集之间的关系 ,以及对称左部属性集存在的条件和性质 ;给出了相关概念、定理及证明 在此基础上 ,给出了关于存在广义左部、右部冲突的判定算法 ,对该算法进行了正确性证明和算法分析

       

      Abstract: The acyclic property of database data structure is an important property of the database theory and application. How to make an acyclic decomposition of the database schema is a relatively complex problem, and more complex is the α-acyclic decomposition problem when there exist inside conflicts in FD set F. Discussed in this paper is that when there exist generalized left-hand side conflicts or generalized right-hand side conflicts in FD set F which has inside conflicts, the relationship between the generalized left-hand side or generalized right-hand side conflicts and the symmetrical left-hand side attribute set, and the existing condition and property of the symmetrical left-hand side attribute set. The corresponding concepts, theorems and proof are also given. On this basis, a decision algorithm of the existence of generalized left-hand side or generalized right-hand side conflicts is presented. The correctness verification and algorithm analysis of the above mentioned algorithm are presented too.

       

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