What is a factless fact table?

• A. Records the occurrence of events without measurable facts.
• B. Stores only summary aggregates.
• C. Holds only dimension attributes.
• D. Contains only surrogate keys.

Answer: (A)

Factless fact tables capture events or relationships without numeric measurements. They store the connections between dimensions using foreign keys (and sometimes a date key) but do not contain measurable facts like counts or amounts. This makes them ideal for recording occurrences such as attendance, enrollments, or event registrations, where you want to know that something happened and “by whom, when, and in what context,” but there’s no value to sum or average.

That’s why the option describing recording the occurrence of events without measurable facts is the best fit. The other ideas don’t align with a factless fact table: storing only summary aggregates implies measured data; holding only dimension attributes describes a pure dimension table; containing only surrogate keys focuses on the keys themselves rather than the event occurrence without facts.