DDLS476 - Extension category #NONE is not combinable

SAP Error Message - Details

• Message type: E = Error

• Message class: DDLS - For DDL source handling

• Message number: 476

• Message text: Extension category #NONE is not combinable

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message DDLS476 - Extension category #NONE is not combinable ?

  The SAP error message DDLS476, which states "Extension category #NONE is not combinable," typically occurs during the process of modifying or extending database objects in the Data Dictionary (DDLS) of SAP. This error indicates that there is an issue with the extension category of the database object you are trying to modify.
  Cause:
  
  Invalid Extension Category: The error arises when the extension category of the object is set to #NONE, which means that the object cannot be extended or combined with other objects.
  Incompatible Object Types: You may be trying to combine or extend objects that are not compatible with each other due to their defined extension categories.
  Database Constraints: There may be constraints in the underlying database that prevent the combination of certain object types.
  
  Solution:
  
  Check Object Definition: Review the definition of the object you are trying to modify. Ensure that the extension category is set correctly and is compatible with the intended operation.
  Modify Extension Category: If applicable, change the extension category of the object to a valid one that allows for combination or extension. This may involve adjusting the object’s properties in the Data Dictionary.
  Consult Documentation: Refer to SAP documentation or the Data Dictionary documentation for guidance on valid extension categories and their combinations.
  Use Transaction Codes: Utilize transaction codes like SE11 (Data Dictionary) to inspect the object and its properties.
  Check for Dependencies: Ensure that there are no dependencies or constraints that would prevent the modification of the object.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional context.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have found.
  Version Compatibility: Ensure that you are working with a compatible version of SAP, as certain features and behaviors may vary between versions.
  
  If the issue persists after trying the above solutions, it may be beneficial to consult with an SAP Basis or ABAP consultant who can provide deeper insights into the specific configuration and context of your SAP environment.