How To Fix CNV_DMC_MC034 - &1: Data type/length of fields do not match; note that data may be lost

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_MC - Migration Object Modeler

• Message number: 034

• Message text: &1: Data type/length of fields do not match; note that data may be lost

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC034 - &1: Data type/length of fields do not match; note that data may be lost ?

  The SAP error message CNV_DMC_MC034 indicates that there is a mismatch between the data type or length of fields during a data migration or conversion process. This error typically arises in the context of using the SAP Data Migration Cockpit (DMC) or during data transfer processes where the source and target systems have different data structures.
  Cause:
  
  Data Type Mismatch: The source field may have a different data type compared to the target field. For example, a source field might be defined as a string (CHAR) while the target field is defined as a numeric type (INT).
  Length Mismatch: The length of the data in the source field may exceed the length defined for the target field. For instance, if the source field has a length of 50 characters and the target field is defined to accept only 30 characters, this will lead to data truncation.
  Inconsistent Data Structures: The data model in the source system may not align with the data model in the target system, leading to discrepancies in field definitions.
  
  Solution:
  
  Review Field Definitions: Check the field definitions in both the source and target systems. Ensure that the data types and lengths are compatible.
  Adjust Data Mapping: Modify the data mapping configuration in the migration tool to ensure that the source fields are correctly mapped to the target fields. This may involve changing the target field definitions or adjusting the source data.
  Data Transformation: If necessary, implement data transformation rules to convert the data types or truncate the data to fit the target field definitions.
  Testing: Conduct thorough testing of the migration process with a subset of data to ensure that the changes resolve the issue without causing data loss.
  Consult Documentation: Refer to SAP documentation or notes related to the specific migration scenario you are working on for additional guidance.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may provide additional insights or solutions for this specific error message.
  Data Migration Cockpit (DMC): Familiarize yourself with the functionalities and capabilities of the SAP Data Migration Cockpit, as it provides tools for data mapping, transformation, and validation.
  Data Quality Checks: Implement data quality checks before migration to identify potential issues with data types and lengths early in the process.
  
  By addressing the root cause of the mismatch and ensuring that the data structures are aligned, you can resolve the CNV_DMC_MC034 error and proceed with your data migration successfully.