How To Fix /BOBF/TOOLS_CC028 - Assoc. has cardinality 1:1 but sourcekey is more than once in ET_KEY_LINK

SAP Error Message - Details

• Message type: E = Error

• Message class: /BOBF/TOOLS_CC -

• Message number: 028

• Message text: Assoc. has cardinality 1:1 but sourcekey is more than once in ET_KEY_LINK

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /BOBF/TOOLS_CC028 - Assoc. has cardinality 1:1 but sourcekey is more than once in ET_KEY_LINK ?

  The SAP error message /BOBF/TOOLS_CC028 indicates a problem related to the cardinality of associations in the Business Object Processing Framework (BOPF). Specifically, it suggests that there is an association defined with a cardinality of 1:1, but the source key is appearing more than once in the ET_KEY_LINK table. This inconsistency can lead to issues when trying to retrieve or manipulate data.
  Cause
  The error typically arises from one of the following scenarios:
  
  
  Data Integrity Issues: The underlying data in the database may have duplicates for the key that is supposed to be unique. This can happen due to incorrect data entry, data migration issues, or bugs in the application logic.
  
  
  Incorrect Configuration: The BOPF model may be incorrectly configured, where the association cardinality does not match the actual data model. For example, if the association is defined as 1:1 but the data allows for multiple entries, this will trigger the error.
  
  
  Business Logic Errors: There may be issues in the business logic that lead to the same key being processed multiple times, violating the expected cardinality.
  
  
  Solution
  To resolve the error, you can take the following steps:
  
  
  Check Data for Duplicates:
  
  Query the database to check for duplicates in the table associated with the BOPF object. Ensure that the key defined for the 1:1 association is unique.
  Use SQL queries to identify and resolve any duplicate entries.
  
  
  
  Review BOPF Configuration:
  
  Verify the BOPF configuration for the associations. Ensure that the cardinality defined in the BOPF model matches the actual data model.
  If necessary, adjust the cardinality in the BOPF configuration to reflect the actual data relationships.
  
  
  
  Debug Business Logic:
  
  Review the application logic that interacts with the BOPF object. Ensure that it correctly handles the associations and does not inadvertently create multiple entries for the same key.
  Implement error handling to manage cases where duplicates might be introduced.
  
  
  
  Data Cleanup:
  
  If duplicates are found, you may need to clean up the data. This could involve deleting or merging duplicate records to ensure that the data integrity is maintained.
  
  
  
  Testing:
  
  After making changes, thoroughly test the application to ensure that the error no longer occurs and that the data integrity is maintained.
  
  
  
  Related Information
  
  BOPF Documentation: Review the official SAP documentation on BOPF to understand how associations and cardinalities work.
  SAP Notes: Check for any relevant SAP Notes that might address this specific error or provide additional guidance.
  Community Forums: Engage with SAP community forums or support channels for insights from other users who may have encountered similar issues.
  
  By following these steps, you should be able to identify the root cause of the error and implement a solution to resolve it.