What is a fact, and what are the different types of facts?

Question

Accepted Answer

A fact is a measurable piece of data that represents a specific business aspect. Types include additive, semi-additive, and non-additive facts.

A fact is a piece of data that can be measured and analyzed in a data warehouse
Additive facts can be aggregated across all dimensions, such as sales amount
Semi-additive facts can be aggregated across some dimensions, such as inventory levels
Non-additive facts cannot be aggregated, such as average temperature