BCNF
BCNF, or Boyce-Codd Normal Form, is a normal form used in relational database design. A relation R is in BCNF if every non-trivial functional dependency X -> Y that holds on R has X as a superkey of R (trivial dependencies are exempt). Equivalently, for any non-trivial FD X -> Y, X must functionally determine all attributes of R.
BCNF is a stricter condition than Third Normal Form (3NF). Every BCNF relation is also in 3NF,
A simple illustration: a relation R(A, B, C) with the dependency A -> B. Here A+ = {A, B},
A standard decomposition approach for a violating FD X -> Y is to replace R with R1 =
BCNF remains a fundamental tool for reducing redundancy and update anomalies, with the trade-off that more