SQLAdvanced#normalization

What is BCNF?

Boyce-Codd Normal Form is a stricter 3NF: for every functional dependency X → Y, X must be a super key. It removes anomalies that 3NF can still allow with overlapping candidate keys.

Example
teacher_subject(student, subject, teacher) with teacher → subject violates BCNF.
Split into teacher(teacher, subject) and student_teacher(student, teacher).

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