Understanding Partial Dependencies and Normal Forms

The question asks to identify the normal form that specifically targets the elimination of partial dependencies. A partial dependency occurs in a relation with a composite primary key when a non-key attribute is functionally dependent on only a *part* of the primary key, not the whole key.

Role of Second Normal Form (2NF)

Second Normal Form (2NF) is designed precisely to address and remove partial dependencies.

• A relation is in 2NF if it is in 1NF and every non-key attribute is fully functionally dependent on the *entire* primary key.
• To achieve 2NF, any relation that has partial dependencies must be decomposed into smaller relations where each non-key attribute depends on the whole primary key of its respective relation.

Comparison with Other Normal Forms

• 1NF (First Normal Form): Ensures atomicity of attributes and eliminates repeating groups. It does not specifically deal with partial dependencies.
• 3NF (Third Normal Form): Builds upon 2NF by eliminating transitive dependencies (where a non-key attribute depends on another non-key attribute).
• BCNF (Boyce-Codd Normal Form): A stricter form than 3NF, ensuring that for every functional dependency $X \to Y$, $X$ is a superkey. While it addresses dependencies, 2NF is the specific form focused on partial dependencies.

Conclusion

Therefore, 2NF is the normal form that specifically addresses and eliminates partial dependencies.