Normalization & Schema Design · SQL SQL
Which of the following describes a Boyce-Codd Normal Form (BCNF) violation?
Practice question from Normalization & Schema Design (SQL SQL), with the correct answer and a step-by-step solution.
medium · MCQ · Q-C540C7
Which of the following describes a Boyce-Codd Normal Form (BCNF) violation?
- A.A non-prime attribute depends on a proper subset of a candidate key.
- B.A non-prime attribute depends on another non-prime attribute.
- C.A functional dependency exists where the left-hand side is not a superkey, but the right-hand side is a prime attribute.
- D.A functional dependency exists where the left-hand side is not a superkey, regardless of whether the right-hand side is prime or non-prime.Correct answer
Solution
BCNF is stricter than 3NF. A relation is in BCNF if and only if for every non-trivial functional dependency X -> Y, X is a superkey. If X is not a superkey, it is a BCNF violation, even if Y is a prime attribute.
More from Normalization & Schema Design
- What is the primary objective of normalizing a database to the Third Normal Form (3NF)?
- A relation R(A, B, C, D) has the functional dependencies F = {AB -> C, C -> D, D -> A}. What is the highest normal form satisfied by R?
- When is intentional denormalization typically justified in a production relational database?
- What type of data anomaly occurs when deleting a record inadvertently causes other unrelated domain information to be lost from the databas…
Practise more SQL
Sign up free for adaptive practice on this chapter, with instant feedback and hints on every question.
Start practising freeFree to start · No credit card needed