In this guide, you will learn the difference between Denormalization and Normalization.
What is Denormalization
Denormalization is a process of adding redundant data to tables in order to get faster response time for read operations. However this better performance comes with a cost of storing redundant data that occupies additional storage in the database.
Denormalization is covered in detail with examples here.
What is Normalization
Normalization is a process of breaking the table into multiple tables in such a way so that the redundant data is reduced. This removes data inconsistencies and helps maintaining DBMS ACID properties.
Normalization is covered in detail with examples here.
Denormalization vs Normalization
| Denormalization | Normalization |
|---|---|
| It provides faster data access as costly time intensive join operations are not required. | Data access (or read) is slower as the join operations are required when accessing data from multiple tables. |
| SQL queries are easy to write as it involves less tables. | SQL queries are complex as they usually involve multiple tables. |
| Redundant data is present. | No redundant data exists. |
| Data inconsistencies are present as same data is available at more than one tables due to data redundancy. | No data inconsistencies as normalization removes data redundancy. |
| Data write operations are slower due to redundant data. | Data write operations are faster. |
| Requires more storage. | Requires less storage. |