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 or SE11) to check for duplicate entries in the specified table for the key field. 
  Example SQL query: 
  SELECT &2, COUNT(*) 
  FROM &1 
  GROUP BY &2 
  HAVING COUNT(*) > 1;
  
  This will help you identify which values are duplicated.
  
  
  
  Data Cleansing:
  
  Once duplicates are identified, you need to decide how to handle them. Options include:
  
  Deleting duplicate records.
  Merging records if they contain complementary information.
  Updating records to ensure uniqueness.
  
  
  
  
  
  Review Data Entry Processes:
  
  Ensure that data entry processes include checks for uniqueness where necessary. Implement validation rules to prevent future duplicates.
  
  
  
  Adjust Configuration:
  
  If the error is due to a misconfiguration in the data quality rules or mining process, review and adjust the configuration settings to align with the actual data structure.
  
  
  
  Testing:
  
  After making changes, test the process again to ensure that the error does not occur and that the data quality rules or mining processes work as expected.
  
  
  
  Related Information:
  
  SAP Documentation: Refer to SAP Help Portal or specific documentation related to data quality management and mining processes for more detailed guidance.
  Transaction Codes: Familiarize yourself with relevant transaction codes such as SE16 (Data Browser), SE11 (Data Dictionary), and others that can help in analyzing and managing data.
  Data Governance: Consider implementing a data governance framework to maintain data quality and integrity across your SAP system.
  
  By following these steps, you should be able to resolve the CM_MDQLTYRULEMINING021 error and ensure that your data meets the required uniqueness constraints.