Cause
Another conflicting DDL was already running.
Another conflicting DDL was already running.
find tables with subpartitions which span the tablespace being dropped and some other tablespace(s). Drop these tables or move subpartitions to a different tablespace
Try the following links for this error:
https://support.oracle.com/rs?type=doc&id=1539723.1
https://support.oracle.com/rs?type=doc&id=1561753.1
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
https://community.oracle.com/message/10117023
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