How To Fix DMCLG272 - Access plan calculation failed

SAP Error Message - Details

• Message type: E = Error

• Message class: DMCLG - DMC Tool Development

• Message number: 272

• Message text: Access plan calculation failed

What causes this issue?

The access plan calculation for an initial load of a table failed.

System Response

The system cancels the access plan calculation, sets the table status to
Failed, and does not transfer the data from the table to the target
system.

How to fix this error?

Check the application logs to find other error messages explaining why
the calculation failed.
If you are using reading type 1, and you encounter messages that contain
statements such as "the block size limit is exceeded" or "a delimitation
is not possible", then chosen selection parameter is not sufficiently
selective. This means that the amount of data in one access plan portion
is too large. You can either use reading type 5, or choose a better
selection parameter. Afterwards, you have to delete and redefine the
migration object.
If you are using SAP LT Replication Server, you can use the performance
options in Advanced Replication Settings (transaction LTRS) to change
the reading type or the selection parameter. You can then use the
relevant processing steps in transaction LTRC to delete the old load and
replication objects.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

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 DMCLG272 - Access plan calculation failed ?

  The SAP error message DMCLG272, which indicates that "Access plan calculation failed," typically arises in the context of database access plans in SAP systems, particularly when dealing with database queries or performance issues. This error can occur for various reasons, including issues with the database statistics, configuration problems, or even data inconsistencies.
  Causes:
  
  Outdated Statistics: The database statistics may be outdated or not properly maintained, leading to inefficient access plans.
  Database Configuration Issues: Misconfigurations in the database settings can lead to problems in generating access plans.
  Data Volume Changes: Significant changes in data volume or distribution can affect the access plan calculations.
  Database Corruption: Corruption in the database or specific tables can lead to failures in access plan calculations.
  Resource Limitations: Insufficient system resources (CPU, memory) can hinder the calculation process.
  
  Solutions:
  
  
  Update Database Statistics:
  
  Use the appropriate database tools or SAP transactions (like DBACOCKPIT) to update the statistics for the affected tables.
  In some cases, you may need to run specific SQL commands to gather statistics.
  
  
  
  Check Database Configuration:
  
  Review the database configuration settings to ensure they are optimized for your workload.
  Consult the database documentation for recommended settings.
  
  
  
  Analyze Query Performance:
  
  Use transaction codes like ST05 (SQL Trace) or ST12 (Single Transaction Analysis) to analyze the performance of the queries that are failing.
  Identify any specific queries that are causing the issue and optimize them if necessary.
  
  
  
  Monitor System Resources:
  
  Check system resource usage (CPU, memory, disk I/O) to ensure that the database has sufficient resources to perform access plan calculations.
  Consider scaling up resources if necessary.
  
  
  
  Database Repair:
  
  If corruption is suspected, run database repair tools or commands as per your database vendor's guidelines.
  In extreme cases, restoring from a backup may be necessary.
  
  
  
  Consult SAP Notes:
  
  Check the SAP Support Portal for any relevant SAP Notes that may address this specific error or provide patches and updates.
  
  
  
  Related Information:
  
  SAP Documentation: Refer to the official SAP documentation for your specific version and database type for detailed troubleshooting steps.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they found effective.
  Database Vendor Support: If the issue persists, consider reaching out to your database vendor's support for assistance, especially if it involves deeper database-level issues.
  
  By following these steps, you should be able to diagnose and resolve the DMCLG272 error effectively.