How To Fix CNV20200148 - New derivation. Existing mapping will be overwritten

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV20200 - Messages for development class CNV_20200

• Message number: 148

• Message text: New derivation. Existing mapping will be overwritten

Self-Explanatory Message

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• What is the cause and solution for SAP error message CNV20200148 - New derivation. Existing mapping will be overwritten ?

  The SAP error message CNV20200148 typically occurs during the data migration process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This message indicates that a new derivation is being created that will overwrite an existing mapping. Here’s a breakdown of the cause, potential solutions, and related information:
  Cause:
  
  Duplicate Mapping: The error arises when there is an attempt to create a new mapping for a data field that already has an existing mapping in the system. This can happen if the same source data is being mapped to multiple target fields or if there are conflicting rules for data transformation.
  Configuration Issues: There may be issues in the configuration of the migration project, such as incorrect settings or misalignment between source and target data structures.
  Data Overlap: The data being migrated may have overlapping values that lead to conflicts in the mapping logic.
  
  Solution:
  
  Review Existing Mappings: Check the existing mappings in the migration cockpit or the relevant migration tool. Identify the mappings that are causing the conflict and determine if they can be modified or removed.
  Adjust Derivation Logic: If the new derivation is necessary, consider adjusting the logic of the existing mapping to accommodate the new requirements without causing an overwrite.
  Consult Documentation: Refer to the SAP documentation for the specific migration tool you are using. There may be guidelines on how to handle mapping conflicts.
  Testing: Before executing the migration, conduct thorough testing in a development or sandbox environment to ensure that the mappings work as intended without conflicts.
  Seek Support: If the issue persists, consider reaching out to SAP support or consulting with an SAP expert who can provide insights based on your specific scenario.
  
  Related Information:
  
  Migration Cockpit: Familiarize yourself with the SAP S/4HANA Migration Cockpit, as it provides tools and guidelines for data migration, including mapping and transformation rules.
  Data Mapping Guidelines: Review best practices for data mapping in SAP, which can help prevent conflicts and ensure smooth data migration.
  SAP Notes: Check for any relevant SAP Notes that may address this specific error message or provide additional troubleshooting steps.
  
  By following these steps, you should be able to resolve the CNV20200148 error and successfully complete your data migration.