The models you already know

Data Vault borrows from normalized (3NF) modeling and from dimensional modeling, and it exists because of where they break. This module is a fast, hands-on refresher of both on Northpaw's data, ending with the two changes that push a star schema past its limits. If you already work with star schemas every day, skim lessons 1 and 2, but don't skip lesson 3.

By the end of this module you can: - explain why operational systems are normalized and analytical models are not; - state the grain of a fact table and choose between type 1 and type 2 for a dimension attribute; - recognize the integration, cardinality and grain changes that force rework in classic models.

Lessons

1. Same data, two shapes
2. Keeping history in a star
3. Where the classic models crack

Then practise with the exercises and check yourself with the module quiz.

Exercises · Module quiz