基于属性相关表的关系模式全部候选关键字求法

A Method for Finding All Candidate Keys of Relational Schema Based On Attributes Relative Table

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（ｎ２）。

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).