How To Fix MDC_GW020 - Locking not allowed

SAP Error Message - Details

• Message type: E = Error

• Message class: MDC_GW - Gateway implementation related messages

• Message number: 020

• Message text: Locking not allowed

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message MDC_GW020 - Locking not allowed ?

  The SAP error message MDC_GW020 "Locking not allowed" typically occurs in the context of the SAP Multi-Dimensional Database (MDC) or when working with SAP HANA. This error indicates that a locking operation is not permitted for the specific object or context you are trying to access or modify.
  Causes:
  
  Locking Mechanism: The error may arise if the system is trying to lock a resource that is not designed to be locked, such as certain types of database objects or during specific operations that do not support locking.
  Transaction State: The error can occur if the transaction is in a state that does not allow locking, such as when a read operation is being performed on a resource that is already locked by another transaction.
  Configuration Issues: There may be configuration settings in the SAP system that restrict locking for certain operations or objects.
  Concurrency Control: The error can also be related to concurrency control mechanisms that prevent multiple transactions from locking the same resource simultaneously.
  
  Solutions:
  
  Check Transaction State: Ensure that the transaction you are trying to perform is in a valid state for locking. If you are performing a read operation, consider whether a lock is necessary.
  Review Object Type: Verify the type of object you are trying to lock. If it is not meant to be locked, you may need to adjust your approach to avoid locking.
  Adjust Configuration: If applicable, review the configuration settings related to locking in your SAP system. Consult with your SAP Basis or system administrator to ensure that the settings align with your operational needs.
  Use Alternative Methods: If locking is not allowed, consider using alternative methods to achieve your goal, such as using optimistic concurrency control or other transaction management techniques.
  Consult Documentation: Refer to SAP documentation or notes related to the specific version of SAP you are using for any known issues or additional guidance on handling this error.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any specific patches or updates related to this error message. SAP frequently releases updates that may address known issues.
  Transaction Codes: Familiarize yourself with relevant transaction codes that may help in diagnosing or resolving the issue, such as ST22 (Dump Analysis) or SM21 (System Log).
  Community Forums: Engage with SAP community forums or support channels where other users may have encountered similar issues and can provide insights or solutions.
  
  If the problem persists after trying the above solutions, it may be beneficial to reach out to SAP support for further assistance.