SAP S/4 HANA Migration Cockpit – Direct Transfer: Creating and using custom field value mapping (LTMOM).
SAP Migration Cockpit is the de-facto tool for moving data to S/4 HANA with 3 different options:
- Direct (from ECC)
Having used File based migration in previous project I saw the major challenge with huge volume of data in source (ECC) and manual effort involved. Direct transfer mechanism was introduced in 1909 which quickly caught my attention and using the resources available in openSAP and various blogs/content I have build the knowledge of designing/defining custom migration object and successfully migrated data.
In this blog I will focus on creating custom field value mapping and how to use it in migration object/s.
Purpose: Step by step details to create field value mapping in Migration Object Modeler for Direct Transfer.
Pre-requisite: Knowledge of SAP Migration Cockpit and LTMOM.
In direct migration one of the significant work is to determine, define and implement field value mapping arising from change of configuration in target (S/4) as compared to source (ECC). A lot of these changes comes from process and data simplification. Some real life examples would be:
- Chart of account harmonization – map source GL to target GL
- Controlling Area/Cost Center/Profit Center harmonization
For SAP standard fields there are mapping rules already defined which can be used as is but there could be scenario where specific mapping may be required for standard fields. E.g. determine Profit Center (in target) using Cost Center (from source) in case profit center was not used or populated in ECC.
On the other hand wherever there are user defined field in source and it needs to be mapped to target value, there comes mandatory requirement of defining a (custom) field value mapping. E.g. coding block / extensions used in source is required to be continued in target (S4).
Lets go through an example.
Requirement: Map Business Partner Group (in S4) based on Vendor Number.
SAP has provided API (/FM) ‘CMD_MIG_BP_CVI_CREATE’ to transfer data. Mapping assignment is done to the importing parameters of the Functional Module in Field Mapping tab of LTMOM’s migration object view.
I will walk through the process to create a field value mapping and assignment to the API/FM.
A custom mapping rule can be defined either at project level or migration object level.
Below steps are performed on Migration Object level and divided in two parts.
Part 1: Creating value mapping
- Goto t-code LTMOM and select the target project / migration object.
- In change mode right click on value mapping and select “Create value mapping”.
- Enter mapping name and description in the popup for “Create Transformation Rule”
- A new popup appears for signature of the mapping rule. Here based on number of importing and exporting parameter/s add as many rows and provide details.
Note: It is possible to define more than one importing parameter based on the requirement. I have successfully created a few in my implementation experience.
- After defining the signature it comes back to original screen – here click on create button
- The value mapping is to be activated where it will prompt to release as well.
Part 2: Assigning value mapping
- Double click on “Target Processing” and go to tab “Field Mapping”
- Right click on target field (GROUPINGMNCENBP) and select “Assign TRule”.
- Here you will see the mapping rule defined visible in “Area Repository”. If you have defined the rule at Project Level then select “Project Repository”.
- Double click on the selected row and a screen layout for further entry appears at the bottom of the screen. Important: Depending on the screen being used / resolution you may have to scroll down and right to view it.
- Another sub-screen appears where importing parameter has to be defined / selected. Press F4 or click giving option to select a field from source structures.
- Select a field as required press save in main transaction (LTMOM). Here i have used LIFNR – vendor number.
Notes to avoid issues:
- The field to be selected in importing/exporting should be compatible with the definition of the field value mapping rule.
- If the mapping is to be used in multiple migration object within the same project create it at project level.
- Before selecting an importing parameter from source structure ensure the corresponding mapping is available in “Structure Mapping” tab of target processing.
Migration cockpit tool if used effectively can bring down manual effort of data transfer and ensure data consistency, auditability. The value mappings definition and usage is the common feature which will be used by SAP customers looking at moving data from ECC source to S/4 HANA target. Hoping my fellow SAP enthusiasts will find the above knowledge article useful to implement field values in migration object/project.