Multiple Choice (circle only one answer):

1) The functional dependency A -> B for relation schema R(A,B,C,D) implies that:

a. No two tuples in R can have the same value for the attribute B

b. Any two tuples in R that have the same value for B must have the same value for A

c. No two tuples in R can have the same value for A

d. Any two tuples in R that have the same value for A must have the same value for B

2) If {A,B} -> {C,D} is the only functional dependency that holds for relation R(A,B,C,D), then:

a. {A,B} is a candidate key for R

b. No two tuples in R can have the same values for both A and B

c. {A,B} is the primary key of R

d. All of the above

3) Given only the relation schema: Books(Title,Author, Year, Publisher) we can infer the following functional dependency:

a. {Author, Publisher} -> Publisher

b. Title -> Author

c. Year -> Publisher

d. Author -> Publisher