How To Fix CM_MDQLTYRULEMINING021 - Key field &2 of table &1 is not unique.

SAP Error Message - Details

• Message type: E = Error

• Message class: CM_MDQLTYRULEMINING - Messages for Rule Mining Run

• Message number: 021

• Message text: Key field &2 of table &1 is not unique.

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CM_MDQLTYRULEMINING021 - Key field &2 of table &1 is not unique. ?

  The SAP error message CM_MDQLTYRULEMINING021 indicates that there is a problem with the uniqueness of a key field in a specified table. This error typically arises in the context of data quality rules or data mining processes where the system expects a key field to be unique, but it has found duplicate entries.
  
  Cause:
  
  Duplicate Entries: The primary cause of this error is that the key field (denoted as &2) in the specified table (denoted as &1) contains duplicate values. This violates the uniqueness constraint that is expected for key fields.
  Data Integrity Issues: There may be underlying data integrity issues in the database, such as incorrect data entry, lack of proper validation, or issues during data migration.
  
  Configuration Issues: Sometimes, the configuration of the data quality rules or the mining process may not align with the actual data structure, leading to this error.
  
  
  Solution:
  
  
  Identify Duplicates: 
  
  Use SQL queries or SAP transaction codes (like SE16