Message Oracle ORA-36201 - (XSAGGR35) Cannot aggregate workspace object(partition workspace object) because the subpartition is itself partitioned.

ERROR(XSAGGR35) Cannot aggregate workspace object(partition workspace object) because the subpartition is itself partitioned.
CAUSEAttempted to aggregate an intermediate partition of a variable with nested partitioning.
ACTIONrerun the aggregate command seperately for each ultimate partition or just for the variable as a whole