Differnce Between Level Based Hierarchy And Parent-Child Hierarchy in OBIEE11g

In 11g Provided New Feature Is Parent - Child Hierarchy.This Post Cover Major Difference Between Level Based  And Parent Hierarchy.

Find Bellow major Differences Here:

1.Level Based Hierarchy:level based Hierarchy Define Level Only.It Used For Level Based Measures.
Ex:Time Dimenssion
Year--Quarter--Month--Week---Day

2.Parent-Child Hierarchy:

Parent Child hierarchies are different from level based hierarchies not only structure and aggregations are Also. For example, in a level based hierarchy, the most common type of aggregation that is done involves rolling up the numbers (Higher Level) from the lower most level. But in the case of parent-child hierarchy, an aggregation by default enforces the roll-up across all descendant members.

A parent-child hierarchy is a hierarchy of members that all have the same type. Consists of values that define the hierarchy in a parent-child relationship and does not contain named levels. This contrasts with level-based hierarchies, where members of the same type occur only at a single level of the hierarchy.

Example:  Employee hierarchy might have no levels, but instead have names of employees who are managed by other employees. Employees can have titles, such as Vice President. Vice Presidents might report to other Vice Presidents and different Vice Presidents can be at different depths in the hierarchy.

Parent Child Hierarchy used for:

·         Each individual in the organization is an employee.

·         Each employee, apart from the top-level managers, reports to a single manager.

·         The reporting hierarchy has many levels.

Conditions for Parent Child Hierarchy:

·         A parent-child hierarchy is based on a single logical table ( "Employees" table)

·         Each row in the table contains two identifying keys, one to identify the member itself, the other to identify the "parent" of the member (for example, Emp_ID and Mgr_ID)

·         Member Key Means ---- Primary Key in the Table.

·         Parent Column -----Top Most Column Id for Manager Levels (Like total).

Finally

·                  Parent Child Hierarchies Is a Value Based Hierarchy

·         Level Base Hierarchies Is A Structure Based Hie.