Factless Fact Table

A factless fact table is a fact table with no numeric measures: each row simply records that an event happened or a condition held — a student attended a class, a product was on promotion on a date, a customer was eligible for an offer. The row itself is the fact; counting rows is the analysis.

The pattern covers two cases: events (things that occurred but have no natural magnitude) and coverage (what could have happened — which, compared against an activity fact, answers questions like “which promoted products didn’t sell?”). A factless table still needs a rigorously declared grain; it just carries context keys and no measures.

Go deeper: Factless Fact Tables, Explained