How To Fix MQ491 - Database access error

SAP Error Message - Details

• Message type: E = Error

• Message class: MQ - Messages for Euro Changeover Package

• Message number: 491

• Message text: Database access error

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

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Smart SAP Assistant

• What is the cause and solution for SAP error message MQ491 - Database access error ?

  The SAP error message MQ491, which indicates a "Database access error," typically arises when there are issues related to database connectivity or data retrieval in the SAP system. Here are some common causes, potential solutions, and related information for this error:
  Causes:
  
  Database Connection Issues: The SAP system may not be able to connect to the database due to network issues, incorrect configuration, or database server downtime.
  Authorization Problems: The user may not have the necessary permissions to access the database or specific tables.
  Database Locking: The database might be locked due to a long-running transaction or deadlock situation.
  Corrupted Data: There may be corrupted data in the database that is causing the access error.
  Configuration Errors: Incorrect settings in the SAP system or database configuration can lead to access issues.
  Resource Limitations: The database server may be running out of resources (e.g., memory, disk space).
  
  Solutions:
  
  
  Check Database Connectivity:
  
  Verify that the database server is up and running.
  Check network connectivity between the SAP application server and the database server.
  Ensure that the database connection parameters (like hostname, port, username, and password) are correctly configured in the SAP system.
  
  
  
  Review User Authorizations:
  
  Ensure that the user encountering the error has the necessary authorizations to access the required database objects.
  Use transaction codes like SU53 to analyze authorization issues.
  
  
  
  Monitor Database Locks:
  
  Use database monitoring tools to check for locks or long-running transactions that may be causing the issue.
  If necessary, resolve locks by terminating the offending transactions.
  
  
  
  Check for Data Corruption:
  
  Run database consistency checks to identify and fix any corrupted data.
  Consult with your database administrator for assistance in resolving data integrity issues.
  
  
  
  Review Configuration Settings:
  
  Check the SAP system configuration and ensure that all settings related to the database are correct.
  Review the database logs for any errors or warnings that may provide additional context.
  
  
  
  Resource Management:
  
  Monitor the database server's resource usage and ensure it has sufficient memory, CPU, and disk space.
  If resource limitations are identified, consider optimizing queries or increasing server resources.
  
  
  
  Related Information:
  
  SAP Notes: Check the SAP Support Portal for any relevant SAP Notes that may address the MQ491 error specifically. SAP Notes often provide detailed troubleshooting steps and solutions.
  Transaction Codes: Familiarize yourself with relevant transaction codes such as SM21 (System Log), ST22 (Dump Analysis), and DB02 (Database Performance Analysis) to gather more information about the error.
  Database Logs: Review the database logs for any error messages or warnings that could provide insight into the cause of the access error.
  
  If the issue persists after trying the above solutions, it may be necessary to engage SAP support or your database administrator for further assistance.