165. AQA A Level SLR23 Normalisation to 3NF
About this video
AQA Specification Reference
A Level 4.10.3
In this video we take a detailed look at the process of normalising a database from unnormalized through to third normal form by stepping through a worked example.
Key questions:
- What is the purpose of normalisation?
- How are 1NF, 2NF and 3NF defined?
- What are the rules of first, second and third normal form?
00:00 Normalisation to 3NF
00:07 Intro
00:12 Database basics recap - Removing repeating/redundant data
00:55 Database basics recap - Relationships
01:12 Database basics recap - Primary keys
01:36 Database normalisation
02:24 Normalisation - 0NF (flat file before any normalisation)
02:45 1NF
06:16 2NF
09:09 A trick for spotting when to split a table
10:12 2NF continued
12:48 3NF
16:20 Database normalisation summary
16:42 Database normalisation continued
20:07 Key questions
20:22 Going beyond the specification
20:34 Database normalisation
20:57 Higher normal forms
22:29 This is all too much!
23:07 Outro
Last updated: 06.11.25
