How To Fix DMC_RT_MSG037 - Duplicate key error; cannot transfer record (migr. object &4, portion &1)

SAP Error Message - Details

• Message type: E = Error

• Message class: DMC_RT_MSG - DMC: Runtime Object Messages

• Message number: 037

• Message text: Duplicate key error; cannot transfer record (migr. object &4, portion &1)

What causes this issue?

The system divides data into portions, which are then transferred to the
target system. The portion above cannot be transferred to the target
system because of a duplicate key error. This means that either one of
the records in the portion already exists in the target table, or at
least one record cannot be inserted, as inserting the record would
violate a unique secondary index for the target table.

System Response

The system does not transfer any records from the portion to the target
system, and sets the status of the table to <ZK>Failed</>. The system
continues to transfer the remaining portions in the access plan.

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?

If you encounter this error when using SAP LT Replication Server,
proceed as follows:
Change the transfer behavior to 3 (Array Modify) so that all records
from the source system will be transferred to the target system. If a
record already exists in the target system, it will be updated with the
record from the source system. For more information, see SAP Knowledge
Base Article (KBA) 2331934.
If you encounter this error when using another application, fix the
issue in the target system (for example by removing the unique secondary
index) or change the transfer behavior as required:
Use transfer behavior 2 (Single Insert) if those records that can be
inserted will be transferred, and the other records that cannot be
inserted (for example, the records that violate a unique secondary
index) will be rejected.
Use transfer behavior 3 (Array Modify) to ensure that all records from
the source system will be transferred to the target system. If a record
already exists in the target system, it will be updated with the record
from source system.
If required, you can use transfer behavior 4 (Array Insert with List of
Duplicate Keys) to identify the keys of the records that cause the
duplicate key 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 DMC_RT_MSG037 - Duplicate key error; cannot transfer record (migr. object &4, portion &1) ?

  The SAP error message DMC_RT_MSG037 indicates a "Duplicate key error" during a data migration process. This error typically occurs when the system attempts to transfer a record that has a key value that already exists in the target database. Here’s a breakdown of the cause, potential solutions, and related information:
  Cause:
  
  Duplicate Records: The source data being migrated contains duplicate records that have the same key values as those already present in the target system.
  Key Constraints: The target database has unique constraints on certain fields, and the incoming data violates these constraints.
  Data Preparation Issues: The data preparation phase may not have adequately handled duplicates, leading to attempts to insert records that already exist.
  
  Solutions:
  
  
  Identify Duplicates:
  
  Review the source data to identify any duplicate records. You can use tools like Excel or SQL queries to find duplicates based on the key fields.
  Use transaction codes like SE16 or SE11 to check the target table for existing records.
  
  
  
  Data Cleansing:
  
  Clean the source data to remove duplicates before migration. This may involve consolidating records or deciding which record to keep based on business rules.
  Ensure that the data is unique for the key fields defined in the target system.
  
  
  
  Adjust Migration Logic:
  
  Modify the migration logic to handle duplicates appropriately. This could involve skipping records that already exist or updating existing records instead of trying to insert them.
  
  
  
  Check Migration Settings:
  
  Review the settings in the Data Migration Cockpit or the tool you are using for migration to ensure that it is configured to handle duplicates as per your requirements.
  
  
  
  Error Handling:
  
  Implement error handling in your migration process to log and report duplicate key errors, allowing for easier troubleshooting.
  
  
  
  Related Information:
  
  Migration Object: The error message references a migration object (indicated by &4), which is the specific object type you are trying to migrate (e.g., customer data, material data).
  Portion: The portion (&1) refers to the specific part of the data being processed when the error occurred.
  SAP Notes: Check SAP Notes for any known issues or patches related to the migration tool you are using. This can provide additional context or solutions.
  Documentation: Review the official SAP documentation for the Data Migration Cockpit or the specific migration tool you are using for best practices and guidelines on handling duplicates.
  
  By following these steps, you should be able to resolve the duplicate key error and successfully complete your data migration process.