题目内容

设有关系模式只(C,P,S,G,T,W),各属性含义为:C课程,P老师,S学生,G成绩,T时间,W教室,其函数依赖集为:F=C→P,(S,C)→G,(T,W)→C,(T,P)→W,(T,S)→W则关系模式的关键字为 (35) ,R的规范化程度最高可达到 (59) 。若将R分解为关系模式组R1 (C,P),R2(S,C,G),R3(S,T,W,C),则R1,R2,R3的规范化程度最高分别可达到 (60) , (61) , (62) 。 (61)处填()。

A. 2NF
B. 3NF
C. BCNF
D. 4NF

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