一、范式判断与函数依赖 第一范式(1NF) 定义:关系模式R中所有属性都是原子域(atom) 约定符号:A属性,α、β属性集,R关系模式。F函数依赖集,F*函数依赖闭包集 1、函数依赖定义:如果存在模式(A,B),则A可以做主码,定义为:A→B 平凡函数依赖(trivial...

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