A hierarchy is used to establish parent-child relationships within your data. For example, suppose you have sales data for the following:
A hierarchy allows you to organize these geographic areas into logical levels (also called nodes), from largest area to the most granular.
The hierarchy column in a dimension is used to store the parent-child values.
In a classic model, the account dimension has only a single hierarchy but multiple are allowed in new model types.
You can add hierarchies by selecting +Add Hierarchy on the toolbar. When you choose this option, a new hierarchy column is inserted into the dimension, and you must enter the name of the new hierarchy.
The hierarchy is visualized in the preview panel in the dimension. You can use drag and drop in the preview panel to arrange the members and build the relationships. If more than one hierarchy has been defined, you can select the one you want to display in the preview from the drop-down list.
General information about hierarchies
An organization and generic type dimension can have one or more level-based hierarchies, or one or more parent-child hierarchies, but not both.
The following types of dimensions hierarchy features:
In a classic model, the account dimension has only a one system-provided parent-child hierarchy but in the new model, multiple account hierarchies are allowed.
For the date dimension, hierarchies are predefined based on the model granularity, and whether you have enabled fiscal time for the model. You can specify a default hierarchy in the settings for the date dimension. In the New Model, additional custom hierarchies may be added.
The version dimension does not have a hierarchy, as different versions are separate and do not have parent-child relationships.