Cause
One of the list values in the ADD SUBPARTITION or ADD VALUES statement already exists in another subpartition
One of the list values in the ADD SUBPARTITION or ADD VALUES statement already exists in another subpartition
Ensure that each of the resulting subpartitions contains atleast 1 value
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
https://community.oracle.com/message/9902849
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