DAX Function Guide

The dates parameter can be any of the following −

• A reference to a date/time column.
• A table expression that returns a single column of date/time values.
• A Boolean expression that defines a single-column table of date/time values.

Constraints on Boolean expressions −

• The expression cannot reference a calculated field.
• The expression cannot use CALCULATE function.
• The expression cannot use any function that scans a table or returns a table, including aggregation functions.

However, a Boolean expression can use any function that looks up a single value, or that calculates a scalar value.

The filter parameter can be a Boolean expression or a table expression that defines a filter.

If the data is filtered, the function changes the context in which the data is filtered, and the expression is evaluated in the new context you define. All current filters on that column are removed for each column used in a filter parameter and instead the filter used in the filter parameter is applied.