Dimension hierarchies allow you to exercise a higher level of control over the number of follow-on queries that are presented to users as they navigate.
For example, in the flat dimension below, a navigation query on the Wine Type dimension value would return six possible refinement queries, one for each child.
This is a simple example, but a large flat dimension with many dimension values is too unwieldy to navigate. The user would be presented with too many potential follow-on queries.
Using hierarchical dimensions reduces this information overload and provides for an easier, more intuitive navigation experience. In the hierarchical example below, the Wine Type dimension value has only three possible refinement queries: Red, White, or Sparkling.
