How To Fix GT838 - Duplicates occurred when inserting in the target table

SAP Error Message - Details

• Message type: E = Error

• Message class: GT - Database utilities

• Message number: 838

• Message text: Duplicates occurred when inserting in the target table

What causes this issue?

Duplicates that could not be inserted in the target table occurred.
This could have occurred when the key was shortened.

System Response

The original table is not deleted so that the original records are
retained.

How to fix this error?

Check the data in the target table. If it does not correspond to your
expectations, this could have been caused by not inserting duplicates.
Please contact the SAP hotline.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message GT838 - Duplicates occurred when inserting in the target table ?

  The SAP error message GT838, which indicates that "Duplicates occurred when inserting in the target table," typically arises during data transfer or data migration processes, particularly when using tools like SAP Data Services, SAP BW, or during ETL (Extract, Transform, Load) operations. This error suggests that the system is attempting to insert records into a target table that already contains duplicate entries based on the defined primary key or unique constraints.
  Causes:
  
  Duplicate Data in Source: The source data may contain duplicate records that violate the uniqueness constraints of the target table.
  Incorrect Data Mapping: The mapping between source and target tables may not be correctly defined, leading to unintended duplicates.
  Concurrency Issues: Multiple processes may be trying to insert the same data simultaneously, causing conflicts.
  Data Transformation Errors: During the transformation phase, data may be altered in a way that creates duplicates.
  Missing or Incorrect Keys: The primary key or unique constraints in the target table may not be properly defined or enforced.
  
  Solutions:
  
  Data Cleansing: Before the data load, ensure that the source data is cleansed to remove duplicates. This can be done using data profiling and deduplication techniques.
  Review Data Mapping: Check the mapping between the source and target tables to ensure that it is correctly defined and that no unintended duplicates are being created.
  Implement Error Handling: Modify the data load process to handle duplicates gracefully, such as skipping duplicate records or logging them for review.
  Adjust Concurrency Settings: If multiple processes are inserting data, consider serializing the data load or implementing locking mechanisms to prevent concurrent inserts of the same data.
  Check Constraints: Review the primary key and unique constraints on the target table to ensure they are correctly defined and enforced.
  Use Staging Tables: Load data into a staging table first, where you can perform deduplication and validation before moving it to the final target table.
  
  Related Information:
  
  SAP Documentation: Refer to SAP's official documentation for specific tools (like SAP Data Services or SAP BW) for best practices on data loading and error handling.
  Transaction Codes: Familiarize yourself with relevant transaction codes (like SE11 for table definitions) to check the structure and constraints of the target table.
  Monitoring Tools: Use monitoring tools available in SAP to track data load processes and identify where duplicates are occurring.
  Community Forums: Engage with SAP community forums or support channels for insights from other users who may have encountered similar issues.
  
  By addressing the root causes and implementing the suggested solutions, you can resolve the GT838 error and ensure successful data insertion into the target table.