How To Fix DMC_RT_MSG166 - ABAP Dictionary changes in parallel to data transfer of object &1

SAP Error Message - Details

• Message type: E = Error

• Message class: DMC_RT_MSG - DMC: Runtime Object Messages

• Message number: 166

• Message text: ABAP Dictionary changes in parallel to data transfer of object &1

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message DMC_RT_MSG166 - ABAP Dictionary changes in parallel to data transfer of object &1 ?

  The SAP error message DMC_RT_MSG166 indicates that there are changes being made to the ABAP Dictionary while a data transfer operation is in progress for a specific object. This situation can lead to inconsistencies or conflicts, as the data transfer process may not be able to correctly handle the changes being made to the structure or definition of the object.
  Cause:
  The primary cause of this error is that the ABAP Dictionary object (like a table, view, or data element) is being modified (e.g., adding fields, changing data types, etc.) while a data transfer operation (such as a data migration or replication process) is ongoing. This can happen in scenarios such as:
  
  Running a data migration tool (like SAP Data Migration Cockpit) while someone is altering the structure of the database table.
  Concurrent processes that are trying to modify the same object.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Pause or Stop the Data Transfer: If you are aware of any ongoing data transfer processes, pause or stop them to allow for the ABAP Dictionary changes to complete.
  
  
  Complete ABAP Dictionary Changes: Ensure that any changes to the ABAP Dictionary are completed and activated. This may involve checking for pending changes in transaction SE11 (Data Dictionary) or SE14 (Database Utility).
  
  
  Retry the Data Transfer: Once the changes to the ABAP Dictionary are complete and no other processes are modifying the object, you can retry the data transfer operation.
  
  
  Check for Locks: Use transaction SM12 to check for any locks on the object that might be causing the issue. If there are locks, you may need to wait for them to be released or resolve them.
  
  
  Review Logs: Check the logs of the data transfer process for any additional information that might help diagnose the issue further.
  
  
  Consult Documentation: If the problem persists, consult SAP documentation or support for specific guidance related to the data transfer tool you are using.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as SE11 (Data Dictionary), SE14 (Database Utility), and SM12 (Lock Entries).
  SAP Notes: Look for SAP Notes related to DMC (Data Migration Cockpit) or the specific data transfer tool you are using for any known issues or patches.
  System Performance: Ensure that your system is not under heavy load, which can sometimes exacerbate issues with concurrent processes.
  
  By following these steps, you should be able to resolve the DMC_RT_MSG166 error and successfully complete your data transfer operation.