Normalisation helps us to structure our database tables effectively in order to improve the performance of the database systems. Once you have a good structured table, it makes easier and more efficient when you retrieve data from the database. √
The main role of normalisation could be also described as removing duplication from the database system. For example if a name of a person appeared in more than one table …show more content…
Data redundancy is minimised, which saves disk space and reduces inconsistencies
It is simpler to modify a small table with small amounts of data than to modify a large complex table.
Security is also improved as the DBA can allow access to limited tables to certain users. Security is easier to control when normalisation has occurred.
Data integrity means the users know they have consistent and accurate data within a database.
Drawbacks of Normalisation
Most databases have some level of normalisation. However this can lead to reduced database performance.
This is because when a query is sent to the database, there are issues involved, such as CPU usage, memory usage, and input/output . A normalized database needs more CPU, memory, and Input/Output to process that query than a deformalized database.
A normalized database has to find the relevent tables and match data from the tables to get the requested information and process