Hierarchies (SAP Library - Administrator Workbench)

Hierarchies

Definition

A hierarchy is a method of displaying a characteristic structured and grouped according to individual evaluation criteria.

Use

Hierarchies are used in two main ways:

Firstly, for structured display of the characteristic values (tree display) in a Presentation Hierarchy.

Second for selection of a defined set of characteristic values as a selection of hierarchy nodes.

Structure

The components of a hierarchy are:

Nodes

A hierarchy is created from nodes. The relationships between the nodes are defined as follows:

The uppermost node is the root. There can be more than one root.

Exactly one other node is directly superior to each node (except for the uppermost node).

There are updateable and non-updateable nodes.

Roots

A hierarchy can have more than one root. They do not have a superior node.

Hierarchy Levels

All nodes on the same level of the hierarchy (nodes that are the same distance away from the root) form a hierarchy level. The roots of a hierarchy form level 1. The level of a node denotes the distance from the node to the root.

Leaves

The leaves of a hierarchy consist of characteristic values for the basic characteristic and therefore can also have entries in the fact table. In contrast to nodes that can be posted, a leaf cannot have any subnodes.

Intervals

Intervals comprise a related set of leaves that is described by its upper and lower boundaries. An interval can be created if a node has more than one leaf. For more information, see Hierarchy Intervals

Basic Characteristics

Hierarchies can be created only for those characteristics that do not reference other characteristics. (see also: Creating InfoObjects: Characteristic).

Example

The characteristic Cost Element can be structured according to cost element groups. The second hierarchy level consists of personnel costs, material costs, administration costs, and so on. Personnel costs are divided up, for example, into the cost element groups pay, salaries, and personnel overhead costs. The cost element group ‘pay’ contains the cost elements ‘individual pay costs’, ‘pay overhead costs’ and ‘other pay costs’.

Another typical example of a characteristic hierarchy is the grouping of the characteristic Region into districts that are themselves sub-divided into areas. This graphic is explained in the accompanying text

Properties

A BW hierarchy has the following properties:

Hierarchies are created for basic characteristics (characteristics that do not reference other characteristics). An example of a basic characteristic is 0COSTCENTER.
Hierarchies are stored in special master data tables. They behave in a similar way to master data, and can therefore be used and modified in all InfoCubes.
You can define several hierarchies for a single characteristic.
A hierarchy can have a maximum of 98 levels.

Integration

You can

load characteristic hierarchies from a source system

The source system can be a SAP system or an external system (BAPI, file). If you want to load a hierarchy from an external system, you have to first maintain the metadata for this hierarchy. You can load a hierarchy directly from a SAP system – the metadata is already delivered with it.

See: Loading Hierarchies

Loading into another BW system using the Data Mart Interface

If you want to use hierarchies from one BW system in another BW system, you must not (and can not) transport them. This is because hierarchies have data (and are not TLOGO objects). You can use the Data Mart Interface to load hierarchies from one BW system into another BW system.

Refer to: Use Data Mart Interface

create characteristic hierarchies manually in the Business Information Warehouse

See: Creating Hierarchies

You also have the option of creating virtual hierarchies using time characteristics. From Customizing, choose BW Customizing Implementation Guide ® Business Information Warehouse ® Reporting Relevant Settings ® General Reporting Settings ® Set F4 Help and Hierarchies for Time Characteristics / OLAP Settings.

If you are working with aggregates and are loading or creating new hierarchies, or changing existing hierarchies, you have to reconstruct the aggregates that are affected by the changes afterwards (see: Adjusting Hierarchy and Attribute Changes).

Prerequisites

You have to determine in the InfoObject-Maintenance whether or not you want the characteristic to be able to have hierarchies. The properties of the valid hierarchies (for example, the Hierarchy Versions, time-dependent hierarchy structure) are also defined here.