How To Fix COM_DIFF_KEY012 - Field name & exists more than once in the internal key fields

SAP Error Message - Details

• Message type: E = Error

• Message class: COM_DIFF_KEY - Messages for Differentiation Key

• Message number: 012

• Message text: Field name & exists more than once in the internal key fields

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message COM_DIFF_KEY012 - Field name & exists more than once in the internal key fields ?

  The SAP error message COM_DIFF_KEY012 indicates that there is a duplicate field name in the internal key fields of a data structure or table. This typically occurs when you are trying to create or modify a data structure, such as a table or a view, and the system detects that the same field name has been defined more than once.
  Cause:
  
  Duplicate Field Definitions: The most common cause is that the same field has been defined multiple times in the key fields of a table or structure.
  Incorrect Data Model: If you are working with a data model that has been incorrectly designed or modified, it may lead to this error.
  Copying Structures: If you have copied a structure or table definition and did not change the field names appropriately, this can lead to duplicates.
  
  Solution:
  
  Check Field Definitions: Review the key fields of the data structure or table where the error is occurring. Ensure that each field name is unique.
  Modify the Structure: If you find duplicate field names, modify the structure to remove or rename the duplicates.
  Recreate the Structure: If the structure is complex and difficult to modify, consider recreating it from scratch with unique field names.
  Use Transaction Codes: Use transaction codes like SE11 (Data Dictionary) to check the definitions of the tables or structures involved.
  Check for Inheritance: If you are using inheritance in your data model, ensure that the inherited fields do not cause duplicates in the derived structure.
  
  Related Information:
  
  Data Dictionary (SE11): This is the primary tool for managing database objects in SAP. You can use it to view and edit table definitions.
  ABAP Dictionary: Understanding how the ABAP Dictionary works can help in managing data structures effectively.
  Documentation: Refer to SAP documentation or help files for more detailed information on data structures and key fields.
  SAP Notes: Check SAP Notes for any known issues or additional guidance related to this error message.
  
  By following these steps, you should be able to resolve the COM_DIFF_KEY012 error and ensure that your data structures are correctly defined without duplicate field names.