Describe the process of converting a table to the domain-key normal form (DK/NF).

Database Normalisation Questions Long



66 Short 80 Medium 49 Long Answer Questions Question Index

Describe the process of converting a table to the domain-key normal form (DK/NF).

The process of converting a table to the domain-key normal form (DK/NF) involves several steps. DK/NF is a higher level of normalization that ensures data integrity and eliminates redundancy in a database. Here is a step-by-step description of the process:

1. Identify the functional dependencies: Analyze the table and identify the functional dependencies between the attributes. A functional dependency occurs when the value of one attribute determines the value of another attribute. For example, in a table of employees, the employee ID determines the employee's name and department.

2. Remove partial dependencies: Identify any partial dependencies, where an attribute depends on only a part of the primary key. To remove partial dependencies, create separate tables for the attributes that depend on only part of the primary key. This ensures that each attribute depends on the entire primary key.

3. Remove transitive dependencies: Identify any transitive dependencies, where an attribute depends on another attribute that is not part of the primary key. To remove transitive dependencies, create separate tables for the attributes that are dependent on other non-key attributes. This ensures that each attribute depends only on the primary key.

4. Create new tables: Based on the identified functional dependencies, create new tables for each set of attributes that depend on the same key. Each table should have a primary key that uniquely identifies the records in that table.

5. Define relationships: Establish relationships between the newly created tables using foreign keys. The foreign key in a table refers to the primary key in another table, creating a link between the two tables.

6. Normalize the new tables: Apply normalization techniques, such as first normal form (1NF), second normal form (2NF), and third normal form (3NF), to the newly created tables. This ensures that each table is free from redundancy and follows the principles of normalization.

7. Review and refine: Review the newly created tables and relationships to ensure that they accurately represent the data and meet the requirements of the database. Refine the design if necessary to optimize performance and maintain data integrity.

By following these steps, a table can be converted to the domain-key normal form (DK/NF), resulting in a well-structured and efficient database design.