For each operating concern defined, the system generates standard derivation steps to define all the automatically known dependencies between characteristics. You can display these standard derivation steps by choosing
.You can also change the derivation steps that have been generated automatically and add new steps to them. In this way, you can, for example, define logically dependent chains of derivation steps or make it possible to perform multiple derivation attempts for the same target field.
Example
Example of a Logical Chain
You have defined the characteristics Market Region
and Responsibility Area
. The market region is derived from the country, and the responsibility area is derived from a combination of division and market region.
Source Field | Target Field | |
---|---|---|
Country | Market region | |
Division, Market region | Responsibility area |
In this case, the order of the derivation steps is essential. First, the country and, if possible, the division are determined. Then the market region is derived from the country, and after this the responsibility area can be found. Including the default steps defined by the system for deriving the division and the country, the order of derivation steps is as follows:
Step | Derivation | Derivation Type |
---|---|---|
1 |
| Created automatically by the system; Table lookup in customer master |
2 |
| Created automatically by the system; Table lookup in customer master |
3 |
| User-defined derivation rule |
4 |
| User-defined derivation rule |
Example
Example for Multiple Derivation Attempts
You have defined a separate characteristic Customer group
. You normally want this customer group to be derived from the customer class, which is stored in the customer master table. For some customers, though, you also want the customer group to depend on the division.
To achieve this, you need to create two derivation steps:
Step | Derivation | Derivation Type |
---|---|---|
1 |
| Derivation rule |
2 |
Read customer master and copy the customer class | Table lookups |
For the first step, you need to make the corresponding derivation rule entries to define all the instances where a differentiated customer group should depend on the customer and the division. If no customer group is stored for a given combination of customer and division, the system carries out the second step, which then supplies it from the customer master. If the first step is successful, the second step is not carried out, since the system first checks with each step whether the target field has already been filled.
Note
When you create a new derivation rule, the system always defines Display error message
as the default reaction for instances where no target value is found. To achieve the effect described above, you need to deactivate the error message in step 1. You do this by choosing Attributes
(see Influencing the Standard Derivation Procedure).
The following graphic provides an example of a useful derivation strategy:
Example: Derivation Strategy
To change the standard derivation steps, you can choose from the following options:
Adding to the Standard Derivation Steps
If you have defined your own characteristics and want have their values derived automatically from other characteristics, you need to add your own steps to the standard derivation steps. Moreover, it may also be necessary to create additional steps in order to represent logical chains or multiple derivation attempts.
Changing a Standard Derivation Step
For the standard derivation steps, the system defaults the dependency that usually yields the required result. In rare instances, however, it may make sense to change a default derivation step since characteristics can be determined using different alternative dependencies.
On the other hand, you cannot change all of the standard derivation steps. Only the standard steps for characteristics taken from SAP tables can be changed. The steps for fixed characteristics and unit fields cannot be changed. You can display all modifiable derivation steps by choosing
.Example
You select the characteristics Country
and Customer group
from the customer master table KNA1
. By default, the system derives values for these characteristics based on the sold-to party. If you want to derive values for country and customer group from the ship-to party instead, you need to change the source field for the standard derivation step accordingly.
Deleting a Standard Derivation Step
You can delete all the user-defined derivation steps. In addition, you can delete the standard steps generated by the system provided that they are modifiable (see above). Doing this makes sense if, instead of using a dependency suggested by the system, you want to define your own step to derive the values for a characteristic taken from an SAP table. If you delete a standard step, you should always make sure that you have defined your own step to derive values for that characteristic. If no other step exists for that characteristic, the system will create the deleted step again the next time you generate the environment of your operating concern.
Sorting Derivation Steps
It may be necessary to change the order of the predefined derivation steps in order to achieve a logical sequence of interdependent steps or to define multiple derivation attempts to populate a field.