首页 | 官方网站   微博 | 高级检索  
     

基于属性相关表的关系模式全部候选关键字求法
引用本文:郝忠孝,刘国华.基于属性相关表的关系模式全部候选关键字求法[J].计算机研究与发展,1994,31(6):6-13.
作者姓名:郝忠孝  刘国华
作者单位:东北重型机械学院
摘    要:本文提出了属性相关表这样一种新的概念,定义了相应的运算并研究了它的有关性质及定理,在此基础上提出了用属性相关表求关系模式全部主属性的等级,并给出了用主属性来组合关系模式全部候选关键字的算法,上述算法的时间复杂度均为O(n^2)。

关 键 词:关系模式  属性相关表  候选关键字

A Method for Finding All Candidate Keys of Relational Schema Based On Attributes Relative Table
Hao Zhongxiao, Liu Guohua, and Liu Changlin.A Method for Finding All Candidate Keys of Relational Schema Based On Attributes Relative Table[J].Journal of Computer Research and Development,1994,31(6):6-13.
Authors:Hao Zhongxiao  Liu Guohua  and Liu Changlin
Abstract:In this paper, a new concept-Attributes Relative Table is proposed, operations are defined. and some property and theorem are studied. Based on the attributes relative table, an algorithm to find out all primary attributes of relation schema is proposed and an algorithm to find out all candidate keys of relation schema by means of composition of primary attributes is given. The time complexity of these algorithms are O(n2).
Keywords:Relation schema  attributes relative table  partial attributes relative table  candidate key  
本文献已被 CNKI 维普 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号