Boyce Codd Normal Form (BCNF)
BCNF is extension of 3NF. It is stricter than 3NF. According to Boyce Codd normal form (BCNF),
- For BCNF, the table should be in 3NF.
- For every FD, L.H.S. should be a candidate or super key.
Example: Let’s assume the following student table
The above table holds the following Candidate keys and FD’s
- Candidate key = {RollNo, ID_Card}
- FD = {RollNo → Name, RollNo→ ID_Card, ID_Card → age, ID_Card → RollNo}
The L.H.S. of all the above functional dependencies contains a candidate key or super key. So, the above table is in BCNF.