Normalisation. Un-normalised. We know what data we want to store in our database Organise it into a table. Un-normalised. Un-normalised. Problem: We can’t store more than one piece of data in one field. First Normal Form. Rule: Remove all repeating groups. First Normal Form.
We know what data we want to store in our database
Organise it into a table
We can’t store more than one piece of data in one field
Remove all repeating groups
We have empty fields?
What happens if a student studies four courses?
It’s really complicated to read
We have redundant information
All non-key attributes are dependant on the whole primary key
Make sure all data refers only to the primary key and only the primary key
To make them talk to each other:
What happens if a tutor teaches more than one course?
We get more repeating and redundancy
No attributes are dependant on other non-key attributes
Make sure no data refers anything other than the primary key