Dimension groups versus dimension hierarchy

Dimension hierarchy refines search by eliminating all but one dimension value from a dimension in the navigation state. Dimension groups allow users to select values from each dimension in the group.

Dimension groups allow the user to select dimension values from each of the dimensions contained in them. If the relationships made by a dimension group were instead created using dimension hierarchy, once a dimension value had been selected from one of the branches, then the remaining dimension values would no longer be available for refinement.

For example, in mutual funds data, a user may want to navigate on a variety of performance criteria. A Performance dimension group that contains YTD Total Returns, 1 Year Total Returns, and Five Year Total Returns dimensions would allow the user to select criteria from all three dimensions. If the same relationship had been created using dimension hierarchy, then once a selection had been made from the YTD Total Returns branch, the 1 Year Total Returns and Five Year Total Returns branches would no longer be available for navigation.