Consider the schema R = (A, B, C, D, E, F) on which the following functional dependencies hold:
A ➝ B
B, C ➝ D
E ➝ C
D ➝ A
What are the candidate keys of R?1
AEF, BEF and DEF
2
AEF, BEF and BCF
3
AE and BE
4
AE, BE and DE
Consider the schema R = (A, B, C, D, E, F) on which the following functional dependencies hold:
A ➝ B
B, C ➝ D
E ➝ C
D ➝ A
What are the candidate keys of R?