How To Fix DDLS476 - Extension category #NONE is not combinable

DDLS476 - Overview

• 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

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.

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DDLS476 - Details

• 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