There are two types of Hierarchies used for approval routing.
a. Position Hierarchies
b. Supervisor Hierarchies
Position Hierarchies
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Position Hierarchies are hierarchies that have a JOB/POSITION relationship.
For example, you could have a JOB called BUYER and within BUYER you could have various grades or POSITIONS of BUYER – Junior, Senior and Chief
Each POSITION has an approval limit, so when a purchase order exceeds the limits of the POSITION, the purchase order is forwarded onto the next POSITION in the Hierarchy.
The hierarchy for this JOB/POSITION type of hierarchy is defined on the Position Hierarchy form. When this is complete or is changed, the Fill Employee Hierarchy concurrent process must be run for the new hierarchy to come into effect.
The Position Hierarchy form can be found at PO Navigator – Setup – Personnel – Position Hierarchy
Supervisor Hierarchies
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Supervisor Hierarchies are hierarchies that have an Employee/Supervisor relationship
The supervisor of an employee is defined on the Assignment zone of the Employee form
This type of hierarchy does not use the Position Hierarchy form, but is defined by the employee / supervisor relationship
If the purchase order raised by the employee exceeds the approval limits, the purchase order is forwarded onto the employees’ supervisor, as defined on the Employee form.
Reference
Oracle Metalink and Oracle White Papers
