How To Fix CNV_NCE_BAS109 - 1:1 mapping values for &1 and &2 result in duplicates

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_NCE_BAS - Number conversion engine: messages

• Message number: 109

• Message text: 1:1 mapping values for &1 and &2 result in duplicates

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_NCE_BAS109 - 1:1 mapping values for &1 and &2 result in duplicates ?

  The SAP error message CNV_NCE_BAS109 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that there are duplicate values in the mapping of source and target fields, which violates the requirement for unique mappings.
  Cause:
  The error message "1:1 mapping values for &1 and &2 result in duplicates" suggests that the system has detected that the values being mapped from the source to the target are not unique. This can happen due to several reasons:
  
  Duplicate Source Values: The source data contains duplicate entries for the field being mapped, which leads to multiple records trying to map to the same target value.
  Incorrect Mapping Configuration: The mapping configuration may not be set up correctly, leading to unintended duplicates.
  Data Quality Issues: The source data may have quality issues, such as missing or incorrect identifiers, causing multiple records to be treated as the same.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Identify Duplicates:
  
  Review the source data for duplicates in the fields that are being mapped. You can use SQL queries or data analysis tools to identify duplicate values.
  
  
  
  Clean Up Source Data:
  
  Remove or consolidate duplicate entries in the source data. This may involve data cleansing processes to ensure that each value is unique.
  
  
  
  Adjust Mapping Configuration:
  
  Check the mapping configuration in the migration tool. Ensure that the mapping is set up correctly and that it reflects the intended relationships between source and target fields.
  
  
  
  Use Unique Identifiers:
  
  If possible, use unique identifiers in the source data to ensure that each record can be mapped to a unique target value.
  
  
  
  Test Migration:
  
  After making the necessary adjustments, test the migration process again to ensure that the error is resolved.
  
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may provide additional guidance or fixes related to this error.
  Data Migration Best Practices: Familiarize yourself with best practices for data migration, including data profiling, cleansing, and validation techniques.
  Documentation: Review the documentation for the specific migration tool you are using, as it may contain specific instructions or troubleshooting steps for handling mapping errors.
  
  By following these steps, you should be able to resolve the CNV_NCE_BAS109 error and successfully complete your data migration process.