In HCL Notes, calendar entries can be assigned multiple categories. However, if you need to enforce or select only a single category using a formula, the method depends on where the formula is applied.
You can check the “Entries by Category” view in the calendar or use a selection formula to filter the calendar view by a single category, as shown below:
If you require to display only one category in the Calendar view, use the following selection formula in the view:
@IsMember(“Meeting”; Categories)
This formula will show only calendar entries categorized as “Meeting.”