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Unknown Error An error occurred while saving the document set Error constraint failed UNIQUE constraint failed - error opening Classification Group

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When attempting to open a Classification Group within the Transformation Designer, the following error is encountered:


Unknown Error: An error occurred while saving the document set. Error: constraint failed UNIQUE constraint failed: XXX



The actual root cause of this issue was never determined.



The following steps is a workaround to resolve this issue.  It is recommended to backup any training sets first.

  1. Remove one of the Extraction Groups (EG) that are linked to the problem Classification Group (CG) within the KTA Designer and then release it.
  2. Problem CG should now open in the Transformation Designer and re-release it.
  3. Then in the KTA Designer, readd the removed EG to the CG that was done in Step #1 and release it.
  4. Open CG in the Transformation Designer and re-release.


Level of Complexity 



Applies to  

Product Version Build Environment Hardware
KTA All      


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Article # 3047383
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