Break distinct count measures into separate measure groups

This rule analyzes distinct count measures to determine whether each distinct count measure group is in its own measure group.

Best Practices Recommendations

Typically, the best performance occurs when each distinct count measure is in its own measure group, and that measure group has the same dimensionality as the initial measure group.

For More Information

For more information about distinct count measures, see Using Aggregate Functions in SQL Server Books Online. 

For more information about performance issues related to distinct count measures, see the section, "Optimizing distinct count," in the SQL Server 2005 Analysis Services Performance Guide.