A fact table, also called an event or transaction table, records specific business events measured at particular moments. It provides the event-level foundation for analysis. section 2.3.1
Fact tables commonly sit within a normalized data warehouse alongside item tables, which describe products or event details, and dimension tables, which add descriptive context such as location or category. section 2.3.1
Typical fact-table events include:
- An order placed on an e-commerce platform. section 2.3.1
- A credit-card transaction in banking. section 2.3.1
- A doctor’s visit in healthcare. section 2.3.1
- A user clickstream event on the internet. section 2.3.1
SELECT df1.product_id, df1.product_name, df1.price, df2.product_description, df2.category, df3.manufacturer, df3.weight FROM df1 JOIN df2 ON df1.product_id = df2.product_id JOIN df3 ON df1.product_id = df3.product_id;
Use joins to assemble event records with product attributes distributed across related tables. section 2.3.1
