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