Normalisation - Advantages and Disadvantages

Normalisation - Advantages and Disadvantages

1. Advantages

   • 1. The database does not have redundant data, it is smaller in size so less money needs to be spent on storage
   • 2. Because there is less data to search through, it is much faster to run a query on the data
   • 3. Because there is no data duplication there is better data integrity and less risk of mistakes.
   • 4. Because there is no data duplication there is less chance of storing two or more different copies of the data
   • 5. Once change can be made which can instantly be cascaded across any related records.

2. Disadvantages

   • 1. You need to be careful with trying to make data atomic. Just because you can split some types of data further, it isn't always necessarily the correct thing to do.
   • 2. You can end up with more tables than an unnormalised database
   • 3. The more tables and the more complex the database, the slower queries can be to run
   • 4. It is necessary to assign more relationships to interact with larger numbers of tables
   • 5. With more tables, setting up queries can become more complex