Thursday 27 February 2014

What is Hierarchy? & Types of Hierarchies with Example


What is Hierarchy? & Types of Hierarchies with Example

              A Hierarchy means arrangement of Items. In SSAS is based on multidimensional databases because it quite literally is. You do business analysis by observing the relationship between dimensions like Time, Sales, Products, Geography, and Accounts. Dimensions are most often made up of several hierarchies.

               Hierarchies are logical entities by which a business user might want to analyze Fact data. Each Hierarchy can have one or more levels. When you come to the end of the level of a tree you find a leaf. At the end of the levels of a hierarchy you find leaf members.

Types of Hierarchy
· Balanced Hierarchies
· Unbalanced Hierarchies
· Ragged Hierarchies

Balanced Hierarchies:
Completely balanced hierarchy means that all leaf (end) members would be equal distance from the Top level.

Date Hierarchy is the best example of Balanced Hierarchy




Unbalanced Hierarchies:
Unbalanced hierarchy means that all leaf (end) members would be not equal distance from the Top level.

Organization Chart is a Best Example of Unbalanced Hierarchy. There are different depths to the chain of supervisor to employee that is the leaf nodes are different distances from the top level node.




Ragged Hierarchies:
                Ragged Hierarchy means that all leaf (end) members are not directly linked with the next level of the tree. In this Hierarchy some intermediate levels are missing that reason low level members are connect with higher level members without any intermediate level members.

                An example of Ragged Hierarchy is shown below that contains levels Employees, TL’s and TM’s. With In Team Manager you have Team leader and Employees. Every time the employees reporting to the TL and finally all TL’s are submitted report to TM. But some of Employees like 4 & 5 directly reporting to TM without dependency of TL.

A Hierarchy in which the members descend to members in the lowest level with different paths is referred to as Ragged Hierarchy.