Cause
The user attempted to create a "\SQL Tuning"\ Set using a name that already exists for that owner.
The user attempted to create a "\SQL Tuning"\ Set using a name that already exists for that owner.
Change the name of the SQL Tuning Set and retry the operation.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
https://community.oracle.com/message/4600522
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