Cause
The user attempted to remove a SQL Tuning Set reference that does not exist. The user might not own the reference.
The user attempted to remove a SQL Tuning Set reference that does not exist. The user might not own the reference.
Check the reference ID and the reference owner 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/9170912
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