Factless Facts

On the outlook it seems an interesting term but also contradictory.

A confusion arises straightaway; Is it a fact? But the term says factless!!

Before we get to the definition of factless facts, lets quickly revisit the definition of fact tables- “Fact Tables consist of the measurements or metrics of a business process”

Now let’s look into in the definition of Factless Facts and seize the difference.

“Factless fact table is a fact table that does not contain any quantitative measures and are so called because they simply contain keys which refer to the dimension tables”.

(There are some tables that may not contain any straightforward measures like SalesAmount or QuantitySold, however they contain relations between Dimensionskeys and are facts in themselves).

Let us see the below example to ease the understanding:

Consider the scenario where a Project Manager wants to track the details of the leave taken by his team member during a certain period.

                                               

As we can see that there is one fact table(Fact_Employee_Leave_Type) in the centre which mapped to 3 dimensional tables.

The Fact table has no measures but still it provides a detail of employee taking a leave on particular day and its type.

*Tracking the no. of leaves taken by employees is helpful. But the real analysis will based on the type of leaves taken by employee helping the managers/stakeholders to take appropriate decisions.