How To Fix CNV_NCE_BAS428 - Duplicate one-to-one mapping values found

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_NCE_BAS - Number conversion engine: messages

• Message number: 428

• Message text: Duplicate one-to-one mapping values found

What causes this issue?

Duplicate mapping values found for 1:1 mapping values. The number range
interval is defined by OBJECT = &V1& / SUBOBJECT = &V2& / NRRANGENR =
&V3& / TOYEAR = &V4&.

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?

Return to the <ZK>1:1 Number Mapping Values</> tab page, and enter the
required data.

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_NCE_BAS428 - Duplicate one-to-one mapping values found ?

  The SAP error message CNV_NCE_BAS428: Duplicate one-to-one mapping values found typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that there are duplicate entries in the mapping table that are supposed to have unique one-to-one relationships.
  Cause:
  
  Duplicate Entries: The most common cause of this error is that the mapping table contains duplicate values for a field that is expected to have unique entries. For example, if you are mapping customer IDs, and the same customer ID appears more than once in the mapping table, this will trigger the error.
  Incorrect Data Preparation: The data preparation phase may not have been executed correctly, leading to duplicates being introduced into the mapping data.
  Configuration Issues: There may be issues with the configuration of the migration project or the mapping settings that allow duplicates to be created.
  
  Solution:
  
  Identify Duplicates: Review the mapping table to identify any duplicate entries. You can use SQL queries or data analysis tools to find duplicates based on the key fields that should be unique.
  Remove or Correct Duplicates: Once identified, you can either remove the duplicate entries or correct them to ensure that each entry is unique. This may involve merging records or adjusting the mapping to ensure that each source value maps to a unique target value.
  Validate Mapping: After correcting the duplicates, validate the mapping to ensure that it meets the requirements of the migration process.
  Re-run the Migration: Once the duplicates have been resolved, re-run the migration process to see if the error persists.
  
  Related Information:
  
  Data Migration Tools: Familiarize yourself with the specific data migration tools and their documentation, as they may provide additional insights or features to help manage mapping issues.
  SAP Notes: Check for any relevant SAP Notes or Knowledge Base Articles that may address this specific error or provide additional troubleshooting steps.
  Testing: Always perform thorough testing in a development or sandbox environment before executing migrations in production to catch such issues early.
  
  By following these steps, you should be able to resolve the CNV_NCE_BAS428 error and successfully complete your data migration.