Which of the following scenarios violates Boyce-Codd

Solution

BCNF is a stricter version of 3NF. A table is in BCNF if, for every functional dependency X→YX , X is a superkey. If a candidate key determines another candidate key, it creates redundancy and violates BCNF. For instance, consider a table where StudentID and CourseID are candidate keys, but CourseID determines StudentID. This means there are multiple possible combinations leading to redundancy. Why Other Options Are Incorrect:

• Option A: This scenario adheres to both 3NF and BCNF, as all non-key attributes depend only on the primary key.
• Option B: This violates 2NF due to partial dependency but does not directly address BCNF.
• Option C: This violates 3NF by allowing transitive dependency but does not necessarily violate BCNF.
• Option E: This statement is a valid condition for both 3NF and BCNF.