De-normalization is used to optimize the readability and performance of the database by adding redundant data. It covers the inefficiencies in the relational database software. De-normalization logical data design tend to improve the query responses by creating rules in the database which are called as constraints.

Examples include the following:

- Materialized views for implementation purpose such as:

- Storing the count of “many” objects in one-to-many relationship

- Linking attribute of one relation with other relations

- To improve the performance and scalability of web applications