---
title: "09-data-modelling-and-normalisation"
tags: 
- info201 
- lecture
sr-due: 2022-06-18
sr-interval: 31
sr-ease: 250
---

- [redundancy-and-anomalies](notes/redundancy-and-anomalies.md)
- [dependencies](notes/dependencies.md)

wia functional dependecy::when some attribute has exactly one associated other attribute 
wia transitive dependency:: A→B, B→C [Transitive dependency](notes/dependencies.md#Transitive%20dependency) <!--SR:!2022-5-521,3,250-->
wia partial dependency:: when a subset of the left determines the right<!--SR:!2022-5-521,3,250-->
wia multivalued dependency::when something has a set of associated values of another attribute 

- [normalisation](notes/normalisation.md)

what is normalisation::formal process of eliminanting unnecessary redundancy in relations by splitting relations into smaller chunks