Default Hierarchy and Member

Each dimension has a default hierarchy associated with it and each hierarchy may have a default member. These defaults are used in the following scenarios:

The DIMENSIONS rowset has a column called DEFAULT_HIERARCHY that indicates the default hierarchy for a dimension. The HIERARCHIES rowset has a column called DEFAULT_MEMBER that indicates the default member of the hierarchy. Also, the expressions dimension.DEFAULTMEMBER and hierarchy.DEFAULTMEMBER may be used to explicitly select the default member of a dimension or hierarchy.

Note   The default member of a dimension is just the default member of the default hierarchy of that dimension.

OLE DB for OLAP does not require that every dimension of every hierarchy have a default member. Applications must check to see if a default exists before using it in an expression.