How To Fix COM_DIFF_KEY027 - Table &1 already contains key to key type &2

SAP Error Message - Details

• Message type: E = Error

• Message class: COM_DIFF_KEY - Messages for Differentiation Key

• Message number: 027

• Message text: Table &1 already contains key to key type &2

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.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message COM_DIFF_KEY027 - Table &1 already contains key to key type &2 ?

  The SAP error message COM_DIFF_KEY027 indicates that there is an attempt to insert a key into a table that already contains a key of the same type. This typically occurs in the context of configuration or master data management, particularly when dealing with tables that require unique keys for entries.
  Cause:
  The error is caused by trying to add a new entry to a table where a key of the same type already exists. This can happen in various scenarios, such as:
  
  Attempting to create a new record in a configuration table where the key already exists.
  Data migration or upload processes where duplicate keys are being introduced.
  Manual entry of data that conflicts with existing records.
  
  Solution:
  To resolve the error, you can take the following steps:
  
  
  Check Existing Records: 
  
  Use transaction codes like SE11 (Data Dictionary) or SE16 (Data Browser) to view the contents of the table specified in the error message. Look for existing entries with the same key type.
  
  
  
  Identify Duplicates:
  
  If you are performing a data upload or migration, ensure that the data being uploaded does not contain duplicates. You may need to clean or preprocess the data to remove duplicates.
  
  
  
  Modify the Key:
  
  If the existing key is valid and should remain, consider modifying the new entry to use a different key that does not conflict with existing entries.
  
  
  
  Consult Documentation:
  
  Review the relevant SAP documentation or configuration guides for the specific table and key type to understand the constraints and requirements.
  
  
  
  Error Handling in Programs:
  
  If this error occurs in a custom program or report, ensure that the logic checks for existing keys before attempting to insert new records.
  
  
  
  Contact Support:
  
  If you are unable to resolve the issue, consider reaching out to SAP support or your internal SAP team for further assistance.
  
  
  
  Related Information:
  
  Transaction Codes: SE11, SE16, SE78 (for data uploads), and others depending on your specific context.
  SAP Notes: Check for any relevant SAP Notes that might address this specific error or provide additional context.
  Data Model: Understanding the data model and relationships between tables can help in diagnosing the issue.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.