How To Fix CNV_PE_GEN126 - Knowledge base inconsistency: extension table is not specified

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_PE_GEN - Messages for object generation

• Message number: 126

• Message text: Knowledge base inconsistency: extension table is not specified

What causes this issue?

Knowledge base entries of parameter &V1& are inconsistent: Extension
table is not specified.

System Response

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

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_PE_GEN126 - Knowledge base inconsistency: extension table is not specified ?

  The SAP error message CNV_PE_GEN126, which indicates a "Knowledge base inconsistency: extension table is not specified," typically arises during data migration or conversion processes, particularly when using SAP's data migration tools or during system upgrades. This error suggests that there is a problem with the configuration of the knowledge base, specifically that an extension table has not been defined where it is expected.
  Cause:
  
  Missing Configuration: The extension table that is supposed to hold additional data related to the main table is not specified in the configuration.
  Incorrect Mapping: There may be an issue with how the data is mapped between the source and target systems, leading to missing references to extension tables.
  Inconsistent Data Model: The data model may not be consistent with the expected structure, possibly due to changes in the schema or missing updates during a migration process.
  Custom Development: If there are custom developments or modifications in the data model, they may not be properly accounted for in the migration or conversion process.
  
  Solution:
  
  Check Configuration: Review the configuration settings in the data migration tool or the relevant transaction to ensure that all necessary extension tables are specified.
  Update Knowledge Base: If you are using a knowledge base for data migration, ensure that it is up to date and correctly configured to include all relevant extension tables.
  Review Mapping: Verify the mapping of fields between the source and target systems to ensure that all necessary fields, including those in extension tables, are correctly defined.
  Consult Documentation: Refer to SAP documentation or notes related to the specific migration or conversion process you are undertaking. There may be specific instructions or prerequisites that need to be followed.
  Debugging: If the issue persists, consider enabling debugging or logging to get more detailed information about where the inconsistency is occurring.
  SAP Support: If you are unable to resolve the issue, consider reaching out to SAP Support for assistance. They may have additional insights or patches that can help resolve the inconsistency.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide guidance on data migration issues.
  SAP Community: Engage with the SAP Community forums where other users may have encountered similar issues and can share their solutions.
  Data Migration Tools: Familiarize yourself with the specific data migration tools being used (e.g., SAP S/4HANA Migration Cockpit, SAP Data Services) and their documentation for best practices and troubleshooting tips.
  
  By following these steps, you should be able to identify and resolve the cause of the CNV_PE_GEN126 error message.