How To Fix CNV_DMC_MC_EXCEPTION121 - Data type &1 is not compatible with data type &2 of domain &3

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 121

• Message text: Data type &1 is not compatible with data type &2 of domain &3

The data type of the fixed value must be compatible with the data type
for the domain. Currently, they are not compatible (the data types and
lengths are not the same):
Data type and length of fixed value <(>&<)>1: CHAR, 6
Data type and length for domain <(>&<)>2: CHAR, 4

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION121 - Data type &1 is not compatible with data type &2 of domain &3 ?

  The SAP error message CNV_DMC_MC_EXCEPTION121 indicates a data type mismatch during a data migration or conversion process. Specifically, it suggests that the data type of a source field (denoted as &1) is not compatible with the data type of the target field (denoted as &2) associated with a specific domain (denoted as &3). This error typically occurs in the context of data migration projects, such as those involving SAP S/4HANA migrations or other data transformation tasks.
  Cause
  The primary causes of this error include:
  
  Data Type Mismatch: The source data type does not match the expected target data type. For example, trying to migrate a character field to a numeric field.
  Domain Constraints: The domain associated with the target field may impose specific constraints that the source data does not satisfy.
  Inconsistent Data: The source data may contain values that are not valid for the target data type, leading to conversion issues.
  Configuration Issues: Incorrect configuration in the data migration tool or settings that define how data types should be handled.
  
  Solution
  To resolve this error, you can take the following steps:
  
  
  Check Data Types: Review the data types of both the source and target fields. Ensure that they are compatible. You may need to adjust the source data or change the target field's data type if possible.
  
  
  Data Cleansing: If the source data contains invalid values, cleanse the data to ensure that it conforms to the expected format of the target data type.
  
  
  Mapping Configuration: Review the mapping configuration in your data migration tool (e.g., SAP Data Migration Cockpit, SAP S/4HANA Migration Cockpit). Ensure that the mappings between source and target fields are correctly defined.
  
  
  Domain Definition: Check the domain definition for the target field. Ensure that the domain allows the values being migrated from the source.
  
  
  Testing: Perform a test migration with a smaller dataset to identify specific records causing the issue. This can help isolate the problem.
  
  
  Consult Documentation: Refer to SAP documentation or notes related to the specific migration tool you are using for any known issues or additional guidance.
  
  
  Seek Support: If the issue persists, consider reaching out to SAP support or consulting with an SAP expert who can provide more tailored assistance based on your specific scenario.
  
  
  Related Information
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional context.
  Migration Tools: Familiarize yourself with the specific migration tools you are using (e.g., SAP S/4HANA Migration Cockpit, SAP Data Services) and their documentation for best practices and troubleshooting tips.
  Data Dictionary: Review the data dictionary (SE11) in your SAP system to understand the definitions of the domains and data types involved.
  
  By following these steps, you should be able to identify and resolve the underlying cause of the CNV_DMC_MC_EXCEPTION121 error.