← Data Engineering & ETL learning pathData Engineering & ETL · Module 4 of 10
Data warehouses and modelling
Design analytics-ready tables.
📖 Key ideas
- Warehouses (BigQuery, Snowflake, Redshift) store data for analysis.
- Fact tables hold events/measures (sales).
- Dimension tables hold descriptive data (customer, product, date).
- Star schema: facts in the centre, dimensions around.
- Slowly changing dimensions track history.
💡 Real-life example: A star schema is a solar system: the fact table is the sun, dimensions orbit around it.
Fact tableMeasurements/events
Dimension tableDescriptive attributes
Star schemaFacts surrounded by dimensions
SCD Type 2Keeps history with new rows