Message type: E = Error
Message class:  CNV_CMIS_A_20 - Message class for Cross-Client Customizing Comparison (SLO) 
Message number: 215
Message text: Additional key field found in table &: relevant
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The SAP error message CNV_CMIS_A_20215 indicates that an additional key field has been found in a table that is relevant for a conversion or migration process. This error typically arises during data migration activities, especially when using SAP's Conversion and Migration tools, such as the SAP S/4HANA Migration Cockpit or other data transfer tools.
Cause: The error is usually caused by one of the following reasons: Schema Changes: The target table structure has changed, and additional key fields have been introduced that were not present in the source system.
Configuration Issues: The mapping or configuration settings in the migration tool may not align with the current structure of the target table. Data Model Changes: If the data model has been altered (for example, during an upgrade or a new implementation), it may lead to discrepancies in expected key fields.
Solution: To resolve this error, you can take the following steps: Check Table Structure: Review the structure of the
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