SQL> create table myTable
2 as
3 select rownum id, a.*
4 from all_objects a
5 where 1=0
6 /
Table created.
SQL>
SQL>
SQL> select owner, last_ddl_time, object_name, object_type
2 from ( select myTable1.*,max(last_ddl_time) over (partition by owner) max_time from myTable myTable1)
3 where last_ddl_time = max_time
4 /
no rows selected
SQL>
SQL>
SQL> drop table myTable;
Table dropped.