Module · Data Engineer
Modeling & Warehousing
Star schemas, slowly changing dimensions and the layers between raw and ready.
TOPIC 01
Dimensional Modelling
Facts, dimensions and the rules that keep a warehouse from turning into a swamp.
What you'll practice
- Design a Star Schema — guided · beginner
- Handle Changing Dimensions — practice · intermediate
A command you'll meet
cat ~/warehouse/model/dimensions.mdThe model is the contract between the people who write the data and the people who query it. Open the task below for the full walkthrough.
Hands-On Tasks in This Topic (2)
Design a Star Schema
A star schema is one fact table surrounded by dimension tables. Write the model document that names the tables, the grain and the joins.
Handle Changing Dimensions
A customer moves, a product is repriced - and yesterday's report must not change. Document the Type 2 pattern that keeps history intact.
TOPIC 02
Layers & Partitions
Raw, cleaned and curated - plus the physical layout that keeps queries fast.
What you'll practice
- Define the Medallion Layers — practice · intermediate
- Partition and Cluster Your Tables — challenge · advanced
A command you'll meet
cat ~/warehouse/model/layers.yamlLayers let you rebuild the clean table without touching the raw one. Open the task below for the full walkthrough.
Hands-On Tasks in This Topic (2)
Define the Medallion Layers
Bronze, silver and gold - three layers with three different contracts. Write the definition so every producer knows where its data belongs.
Partition and Cluster Your Tables
Layout is performance. Decide how the fact table is partitioned, how it is clustered and how long the history is kept.