Follow these rules when tagging a time dimension:
You can tag only one dimension as time.
When you tag a dimension as time, all members in the dimension inherit the time property.
You can create multiple hierarchies inside the dimension tagged as time; for example, you can specify a Year, Quarter, Month hierarchy and a Year, Season hierarchy in the same time dimension.
You can create an outline that does not have a dimension tagged as time.
You can add time members to a dimension that is not tagged as time.
The time dimension and the accounts dimensions are calculated before other dimensions in the database.
You can calculate members of the time dimension on a second pass through the outline. For an overview of two pass calculation, see Two Pass Calculation Overview.