What syntax should a Data Analyst use to find the first purchase date per customer when the customer is not displayed in the view?

To find the first purchase date per customer, the syntax that is appropriate and correct is using the MIN function, specifically { FIXED [Customer ID] : MIN( [Purchase Date]) }. This calculation creates a level of detail (LOD) expression that fixes or aggregates the data at the level of each unique customer identified by the Customer ID.

Using MIN in this context is essential because you want to determine the earliest purchase date for each customer. The MIN function will evaluate all purchase dates associated with that customer and return the earliest one. This aligns perfectly with the objective of finding the first purchase date.

The FIXED keyword allows the calculation to be performed independently of the view, ensuring that you can retrieve the first purchase date even if customers are not displayed in the current visualization. It does not depend on any filters or dimensions presented in the view, making it a highly effective choice for this requirement.

In contrast, other options do not accomplish the intended goal. For instance, using MAX would yield the latest purchase date instead of the first, which does not meet the requirement. The INCLUDE option is designed for cases where you want to consider additional dimensions that are not included in the view, which is not necessary in this scenario. Finally, using AVG is inappropriate