ORA-12812: only one PARALLEL or NOPARALLEL clause may be specified
Cause: PARALLEL was specified more than once, NOPARALLEL was specified more than once, or both PARALLEL and NOPARALLEL were specified in a CREATE TABLE, CLUSTER, or INDEX or in an ALTER TABLE or CLUSTER statement, or in a RECOVER command.
Action: Remove all but one of the PARALLEL or NOPARALLEL clauses and reissue the statement.