i am trying to understand how to normalize a relation to BCNF. The task at hand, involves a relation and a set of functionel dependencies.
They look somewhat in the lines of;
R(A,B,C,D,E)
F {
AB->C
C->D
}
Now i am trying to calculate the keys for R, by calculating the Closure. Problem is, the E attribute is not mentioned in the FD's. So how do i find out what is the Key for the relation?
将琐碎的依赖项ABCDE-> ABCDE添加到F。然后确定键。
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