How To Fix CNV851 - Reloading is not possible for table &. Optimized cluster method is used.

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV - Conversion: Messages for Conversion Services (CNCC)

• Message number: 851

• Message text: Reloading is not possible for table &. Optimized cluster method is used.

Self-Explanatory Message

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• What is the cause and solution for SAP error message CNV851 - Reloading is not possible for table &. Optimized cluster method is used. ?

  The SAP error message "CNV851 Reloading is not possible for table &. Optimized cluster method is used." typically occurs during data migration or data transfer processes, particularly when using the SAP Landscape Transformation (SLT) or SAP Data Services tools. This error indicates that the system is unable to reload data into a specific table because the optimized cluster method is being used for that table.
  Cause:
  
  Optimized Cluster Tables: The error arises because the table in question is an optimized cluster table (e.g., table types like ACDOCA, which is used in S/4HANA). These tables have specific data storage and access methods that do not support certain operations, such as reloading data in the same way as standard tables.
  Data Migration Process: During data migration, if the process attempts to reload data into a table that is not designed to handle such operations, this error can occur.
  Configuration Issues: There may be configuration settings in the data migration tool that are not compatible with the optimized cluster method.
  
  Solution:
  
  Check Table Type: Verify if the table is indeed an optimized cluster table. If it is, you may need to adjust your data migration strategy to accommodate this.
  Use Alternative Methods: Instead of reloading data, consider using other methods such as:
  
  Data Append: If you need to add new records, consider appending data instead of reloading.
  Data Deletion and Reload: If you must reload, you may need to delete existing records first (if applicable) and then perform the load.
  
  
  Adjust Migration Settings: Review the settings in your data migration tool to ensure they are compatible with the optimized cluster method. This may involve changing the way data is processed or loaded.
  Consult Documentation: Refer to SAP documentation or notes related to the specific migration tool you are using for any additional guidance or best practices regarding optimized cluster tables.
  Seek SAP Support: If the issue persists, consider reaching out to SAP support for assistance, especially if this is part of a larger migration project.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional context.
  Migration Tools: Familiarize yourself with the capabilities and limitations of the migration tools you are using (e.g., SAP Data Services, SLT).
  Table Structure: Understand the structure and purpose of the optimized cluster tables in your SAP system, as this can help in planning your data migration strategy effectively.
  
  By following these steps, you should be able to address the error and successfully manage your data migration process.