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Consider Relation  R (A, B, C, D, E, F)    
{    AB->C    C->B    D->C    E->D    F->E    }      
C.key=AF  

I have 2 questions

1) Isn't AB->C fully functionally dependent? Because the definition of full functional dependency states that no proper subset of AB can determine C,which is the case here.

2) Does F->E exhibit partial dependency? How do I determine if its partially dependent?

1 Answer

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Full functional dependency: if x->y then y can not determine by any of the subset of x.

let say BCD->A then A can not determined by B or C or D individually(B->A or C->A or D->A)

Partial Dependency:If AB->C then it is partial dependent if A->C or B->C 

1) AB->C is fully functional dependency

2) F->E is partial dependency because AF is a candidate key and no subset of Candidate Key can determine E  

http://stackoverflow.com/questions/25747802/partial-dependencydatabases

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