Comparing Functional Dependencies
Functional dependencies: a statement about the set of allowable
Entailment and equivalence: comparing sets of functional dependencies
Entailment: a set of functional dependencies S1 entails a set S2 if:
any database that satisfies S1 much also satisfy S2.
Equivalence: two sets of FD’s are equivalent if each entails the
{A B, B C } is equivalent to {A B, A C, B C}