Which type of DAX quick measure calculations will NOT operate against a DirectQuery table?

The type of DAX quick measure calculations that will not operate against a DirectQuery table is time intelligence. Time intelligence functions in DAX rely on date hierarchies and require data to be loaded into memory, which is typically not possible with DirectQuery connections. DirectQuery retrieves data in real-time from the source, limiting the ability to perform complex time-based calculations that depend on in-memory data structure and optimized date table features.

Time intelligence functions, such as calculating year-to-date, month-over-month comparisons, and similar calculations, often expect a relationship with a date table in the model, which ensures effective context and filtering. Since a DirectQuery table does not support these relationships and calculations as traditional imported models do, using time intelligence DAX measures in a DirectQuery scenario will lead to limitations or failures.

Aggregate per category, mathematical operations, and X-functions are not similarly constrained and can function with DirectQuery since they do not rely on in-memory data structures or dynamic relationships like the time intelligence functions do.