Types of hierarchies

The two types of hierarchies that exist in MicroStrategy include:

System hierarchy: The system hierarchy is created according to the relationships defined between the attributes in your project. You do not need to create the system hierarchy; it is automatically created in Developer when you create a project. Although the system hierarchy specifies an ordered set of all attributes in the project, it does not define ordering or grouping among attributes. The ordering and grouping of attributes, among other configurations, is defined in user hierarchies.
User hierarchy: User hierarchies are groups of attributes and their relationships to each other, arranged in ways that make sense to a business organization. They are user-defined and do not need to follow the logical data model. As the structure of your business intelligence system evolves, you can modify the design of a user hierarchy to include additional attributes or limit user access to certain attributes. This type of hierarchy is created to provide flexibility in element browsing and report drilling. Steps to create user hierarchies are discussed in:
Creating user hierarchies, which describes creating user hierarchies with the Hierarchy Editor.
Creating and modifying user hierarchies, which describes creating user hierarchies using Architect.