Design hierarchies

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Hierarchies allow business users to perform drill-down analysis by using a predefined object that contains levels arranged in a logical order.

The calendar hierarchy in the date dimension is a common and simple hierarchy to understand.



















The calendar hierarchy in this example has four member levels consisting of Year, Quarter, Month, and Date. Notice that as you expand the levels of the calendar hierarchy, the [SalesAmount] measure gets broken down to quarterly, monthly, and daily aggregate amounts.

The calendar hierarchy is an example of a natural hierarchy because each attribute can be related to another in a natural order. For example, you can relate dates to a month, months to a quarter, and quarters to a year. This is considered a one-to-many relationship.

Hierarchies that do not follow a natural order are considered unnatural hierarchies. This is considered a many-to-many relationship.

 Exam 70-767

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