How To Fix DMC_RT_MSG170 - Secondary index contains duplicate values; portion &1

SAP Error Message - Details

• Message type: E = Error

• Message class: DMC_RT_MSG - DMC: Runtime Object Messages

• Message number: 170

• Message text: Secondary index contains duplicate values; portion &1

What causes this issue?

During an initial load, you are using transfer behavior 3 (Array
Modify). At least one record in an access plan portion cannot be
inserted or updated, as this would violate a unique secondary index for
the target table.

System Response

The system does not transfer any records from the failed portions to the
target system, but continues transferring the other access plan
portions, and sets the status of the table to <ZK>Failed</>.

How to fix this error?

Remove the unique secondary index from the target table, or change it to
a non-unique secondary index. Then reset the status of table in the
central system. The central system will try to transfer the failed
portions again.

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

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 DMC_RT_MSG170 - Secondary index contains duplicate values; portion &1 ?

  The SAP error message DMC_RT_MSG170 indicates that there are duplicate values in a secondary index for a specific portion of data. This typically occurs during data processing or data migration tasks, particularly when working with the Data Migration Cockpit (DMC) or similar tools in SAP.
  Cause:
  The error is caused by the presence of duplicate entries in the secondary index of a database table. This can happen due to various reasons, such as:
  
  Data Quality Issues: The source data may contain duplicates that were not identified or cleaned before the migration or processing.
  Incorrect Mapping: During data migration, the mapping of fields may not be set up correctly, leading to duplicates being created in the target system.
  Concurrency Issues: If multiple processes are trying to insert or update records simultaneously, it may lead to duplicate entries.
  Configuration Errors: The configuration of the secondary index may not be set up to handle unique constraints properly.
  
  Solution:
  To resolve the DMC_RT_MSG170 error, you can follow these steps:
  
  
  Identify Duplicates:
  
  Use SQL queries or data analysis tools to identify the duplicate entries in the source data. You can check the specific portion mentioned in the error message (e.g., a specific table or field).
  
  
  
  Clean the Data:
  
  Remove or consolidate duplicate entries in the source data. This may involve data cleansing processes to ensure that only unique records are migrated.
  
  
  
  Review Mapping:
  
  Check the mapping configuration in the Data Migration Cockpit or the tool you are using. Ensure that the fields are correctly mapped and that there are no unintended duplications.
  
  
  
  Adjust Index Configuration:
  
  If necessary, review the configuration of the secondary index in the target system. Ensure that it is set up to enforce uniqueness where required.
  
  
  
  Test Migration:
  
  After making the necessary adjustments, perform a test migration with a smaller dataset to ensure that the issue is resolved before proceeding with the full migration.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or support resources for specific guidance related to the Data Migration Cockpit and handling duplicate values.
  
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional troubleshooting steps.
  Data Quality Tools: Consider using data quality tools to help identify and resolve data issues before migration.
  SAP Community: Engage with the SAP Community forums for insights from other users who may have encountered similar issues.
  
  By following these steps, you should be able to resolve the DMC_RT_MSG170 error and ensure a successful data migration or processing task.