When is a Table in BCNF?

4 years ago
Database Management System

Table in BCNF

A table is in Boyce-Codd Normal Form (BCNF) when it is in 3NF and every determinant in the table is a candidate key.

For example, if the table is in 3NF and it contains a nonprime attribute that determines a prime attribute, the BCNF requirements are not met.

A table is in Boyce-Codd Normal Form (BCNF) when it meets the following criteria:

  1. It is in 3rd Normal Form (3NF)
  2. For every non-trivial functional dependency X -> Y, X must be a superkey.

A table in BCNF is considered to be free of all types of anomalies that can occur in 3NF such as insertion, update, and deletion anomalies. It is a stronger form of 3NF and is less prone to data inconsistencies. It is also known as 3.5NF.

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Bijay Satyal
Bijay Satyal
Oct 23, 2021
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