Normalization is an essential concept in database design that helps organize and structure data efficiently. It involves breaking down a table into smaller, more manageable tables to eliminate redundancy and improve data integrity. In this article, we will explore the different normal forms and demonstrate their implementation using SQL Server.

First Normal Form (1NF)

The first normal form (1NF) requires that each attribute in a table contains only atomic values. In the provided example, the “StudentProject” table violates 1NF because the “Sname” column stores both the first name and last name of the student, and the “Saddr” column stores multiple addresses separated by commas.

To achieve 1NF, we create a new table called “StudentProject1NF” with separate columns for first name, last name, and each address. This ensures that each column contains a single, indivisible value.

Second Normal Form (2NF)

The second normal form (2NF) requires that every non-prime attribute is fully dependent on the entire primary key. In the “StudentProject1NF” table, we identify functional dependencies and find that the “Lname”, “Fname”, and “Saddr” columns are partially dependent on the primary key.

To achieve 2NF, we decompose the “StudentProject1NF” table into three new tables: “StudentProject2NF”, “Student2NF”, and “Project2NF”. Each table contains attributes that are fully dependent on the primary key, eliminating partial dependencies.

Third Normal Form (3NF)

The third normal form (3NF) requires that there are no transitive dependencies in a table. In the “StudentProject2NF” table, we find that the “Dname” column is dependent on the “DeptId” column, which is not a candidate key.

To achieve 3NF, we further decompose the “StudentProject2NF” table into two new tables: “StudentProject3NF” and “Department3NF”. This ensures that each table contains attributes that are directly dependent on the primary key or are candidate keys themselves.

Boyce Codd Normal Form (BCNF)

The Boyce Codd normal form (BCNF) requires that every determinant in a table is a candidate key. In the “StudentProject3NF” table, we find that the “GuideId” column is not a super key, violating BCNF.

To achieve BCNF, we decompose the “StudentProject3NF” table into two new tables: “StudentProjectBCNF” and “ProjectGuideBCNF”. This ensures that each table satisfies BCNF by having determinants that are candidate keys.

Conclusion

Normalization is a crucial process in database design to ensure data integrity and eliminate redundancy. By following the step-by-step process of normalization, we can break down a table into smaller, more efficient tables that adhere to the different normal forms. It is important to transfer data correctly during the decomposition process to avoid data loss or redundancy.

Remember, the provided example demonstrates the implementation of normalization concepts in SQL Server, but the actual table and column names can vary based on individual preferences and naming conventions.