Why only one is active
A fact table often has several dates — order date, ship date, due date — all pointing at the same calendar table.
Power BI allows only one active relationship between two tables, because with several it could not decide which to filter through. The others are created as inactive, shown as dashed lines.
By default every date-filtered measure uses the active one.
USERELATIONSHIP
Sales by Ship Date =
CALCULATE(
[Total Sales],
USERELATIONSHIP('Sales'[ShipDate], 'Calendar'[Date])
)USERELATIONSHIP activates an inactive relationship for the duration of that CALCULATE. The active one is suspended while it runs.
So one calendar table serves every date, and you write one measure per date role. Both can then appear in the same visual — sales by order date beside sales by ship date, sharing one date slicer.
Requirements
It only works inside CALCULATE (or a function that takes a filter argument such as CALCULATETABLE), and the relationship must already exist as inactive. It cannot invent one.
It also does not work in a calculated column across certain relationship types — measures are where it belongs.
The alternative
The other approach is a role-playing dimension: load the calendar table several times as Order Date, Ship Date and Due Date, each with its own active relationship.
| USERELATIONSHIP | Duplicate tables | |
|---|---|---|
| Model size | One table | Several copies |
| Field list | One date table | Several, clearly named |
| Slicers | One measure per role | Each table slices independently |
| Complexity | In the DAX | In the model |
Duplicate tables are simpler for report authors, since a slicer on Ship Date filters everything naturally. USERELATIONSHIP keeps the model tidy. Both are legitimate.