Returns the default member of a dimension or hierarchy.
The default member is specified in the Default Member property of the dimension or hierarchy (DefaultMember in the Decision Support Objects library.) If this property is empty and the dimension contains an (All) level, the default member is the All member. If this property is empty and the dimension or hierarchy does not contain an (All) level, the default member is an arbitrary member of the highest level. In this last case, the DefaultMember function is ambiguous.
If the Time dimension has levels (All), Year, Quarter, and Month, and member All-Time, the following expression returns
If the [Fiscal Year] hierarchy has levels Quarter, and Month, and member [Month 1], the following expression returns