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

CNV20200148 - Overview

• 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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CNV20200148 - Details

• 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