So the days has finally arrived, and I can now – after following the lecture and reading the additional material – learned the uses of normalisation. Although it is not “needed” if you are that kind of programmer that does everything superbly correct right away – it is something that should be done every time to make sure the database is normalised.
So what is it? Well, it is a process of five steps (but only takes three):
- Starting point – Un-normalised data
- First normal form (1NF) – Table format. Primary key is identified. All data items are “atomic”.
- Second normal form (2NF) – No partial dependencies!
- Third normal form (3NF) – No transitive dependencies!
- Ending point – Normalised data