How To Fix RD156 - The selected data source is locked by another process

SAP Error Message - Details

• Message type: E = Error

• Message class: RD - CO-PA Connection to SAP BW

• Message number: 156

• Message text: The selected data source is locked by another process

What causes this issue?

Data should be read from a summarization level, but this level is
currently blocked. This could be because it is being updated, for
example. Alternatively, data should be read from the CO-PA line items,
but an update is being carried out.

System Response

The read request cannot be executed.

How to fix this error?

Carry out the read request at a later point in time. The status of the
DataSource is not changed.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message RD156 - The selected data source is locked by another process ?

  The SAP error message RD156, which states "The selected data source is locked by another process," typically occurs in the context of SAP Business Warehouse (BW) or SAP BusinessObjects when a data source is being accessed or modified by another user or process. This can prevent you from executing queries or performing certain operations on that data source.
  Causes:
  
  Concurrent Access: Another user or process is currently accessing or modifying the data source, leading to a lock.
  Long-Running Queries: A long-running query or data load process may have locked the data source.
  System Configuration: Certain configurations in the SAP system may lead to locking issues, especially if the data source is not properly released after use.
  Transaction Management: If a transaction is not properly committed or rolled back, it may leave the data source in a locked state.
  
  Solutions:
  
  Wait and Retry: If the lock is temporary, waiting for a few moments and then retrying the operation may resolve the issue.
  Identify the Locking Process: Use transaction codes like SM12 (for lock entries) or SM21 (for system log) to identify which user or process is holding the lock. You can then coordinate with that user or process to resolve the issue.
  Release the Lock: If you have the necessary authorizations, you can manually release the lock using transaction SM12. Be cautious when doing this, as it may disrupt the work of other users.
  Check for Long-Running Processes: Use transaction ST22 (dump analysis) or SM37 (job monitoring) to check for any long-running jobs that may be causing the lock. If necessary, you can terminate these jobs.
  System Configuration Review: Review the system configuration and settings related to data source locking to ensure they are optimal and not causing unnecessary locks.
  Contact Support: If the issue persists and you cannot identify the cause, consider reaching out to your SAP support team for further assistance.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  Documentation: Review SAP documentation for best practices on managing data sources and understanding locking mechanisms.
  User Training: Ensure that users are trained on how to properly access and release data sources to minimize locking issues.
  
  By following these steps, you should be able to diagnose and resolve the RD156 error in SAP.