Consider a relation R(A,B,C,D) with functional dependencies: $A \rightarrow B$, $B \rightarrow C$, and $A \rightarrow D$.

(a) Identify all candidate keys of R.

(b) State the highest normal form (1NF, 2NF, 3NF, BCNF) that R satisfies.

(c) If R is not in BCNF, decompose it into a set of BCNF relations.

Question

Consider a relation R(A,B,C,D) with functional dependencies: $A \rightarrow B$, $B \rightarrow C$, and $A \rightarrow D$.

(a) Identify all candidate keys of R.

(b) State the highest normal form (1NF, 2NF, 3NF, BCNF) that R satisfies.

(c) If R is not in BCNF, decompose it into a set of BCNF relations.

Accepted Answer

Candidate key: {A}. Highest normal form: not in 3NF (so not BCNF). BCNF decomposition: R1(B,C) and R2(A,B,D).

City Guilds Model Questions Vol1 2022 Information Technology Question 13