How To Fix CNV_DMC_MC_EXCEPTION137 - No key field defined; structure must have at least one key field

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_MC_EXCEPTION - Exception texts of Migration Object Modeller

• Message number: 137

• Message text: No key field defined; structure must have at least one key field

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION137 - No key field defined; structure must have at least one key field ?

  The SAP error message CNV_DMC_MC_EXCEPTION137 indicates that a data structure being processed in the Data Migration Cockpit (DMC) does not have a key field defined. In SAP, key fields are essential for uniquely identifying records in a table or structure. Without at least one key field, the system cannot properly manage or process the data.
  Cause:
  
  Missing Key Field: The structure you are trying to use for data migration does not have any fields defined as key fields.
  Incorrect Configuration: The configuration of the data structure may not have been set up correctly, leading to the absence of key fields.
  Data Model Issues: The data model being used may not be aligned with the requirements of the DMC, which expects certain key fields to be present.
  
  Solution:
  
  
  Define Key Fields:
  
  Go to the data structure definition in the DMC.
  Ensure that at least one field is marked as a key field. This can typically be done in the data model configuration or structure definition screen.
  
  
  
  Review Data Model:
  
  Check the data model you are using to ensure it aligns with the requirements of the DMC.
  If necessary, modify the data model to include appropriate key fields.
  
  
  
  Consult Documentation:
  
  Refer to the SAP documentation for the Data Migration Cockpit to understand the requirements for key fields in your specific context.
  
  
  
  Testing:
  
  After making changes, test the data migration process again to ensure that the error is resolved.
  
  
  
  Related Information:
  
  Data Migration Cockpit (DMC): A tool provided by SAP to facilitate the migration of data from legacy systems to SAP S/4HANA or other SAP systems.
  Key Fields: In SAP, key fields are used to uniquely identify records in a database table. They are crucial for data integrity and consistency.
  SAP Notes and Community: Check SAP Notes for any specific patches or updates related to this error. The SAP Community forums can also be a valuable resource for troubleshooting and solutions shared by other users.
  
  If the issue persists after following these steps, consider reaching out to SAP support for further assistance.