问题
单项选择题
Suppose we have the relation schema R(A,B,C,D) with functional dependencies;F{A→B,B→C,C→D,D→A},then R(A,B,C,D)at least is in
A．1NF
B．2NF
C．3NF
D．BCNF
答案
参考答案：D
搜题请搜索小程序“爱下问搜题”
Suppose we have the relation schema R(A,B,C,D) with functional dependencies;F{A→B,B→C,C→D,D→A},then R(A,B,C,D)at least is in
A．1NF
B．2NF
C．3NF
D．BCNF
参考答案：D
④润滑油⑤花生油⑥石蜡