USERELATIONSHIP Specifies the relationship to be used in a specific calculation as the one that exists between columnName1 and columnName2.
Syntax
USERELATIONSHIP(columnName1,columnName2)
Parameters
ColumnName1 – The name of an existing column, using standard DAX syntax and fully qualified, that usually represents the many side of the relationship to be used; if the arguments are given in reverse order the function will swap them before using them. This argument cannot be an expression.
ColumnName2 – The name of an existing column, using standard DAX syntax and fully qualified, that usually represents the one side or lookup side of the relationship to be used; if the arguments are given in reverse order the function will swap them before using them. This argument cannot be an expression.
Return Value
The function returns no value; the function only enables the indicated relationship for the duration of the calculation.
Reference Data
https://docs.microsoft.com/en-us/dax/dax-function-reference