REM
REM Author of this Code: Tom Kyte
REM
create table bigtab
as
select rownum id, a.*
  from all_objects a
 where 1=0;

alter table bigtab nologging;

declare
    l_cnt number;
    l_rows number := 1000000;
begin
    insert /*+ append */
    into bigtab
    select rownum, a.*
      from all_objects a;

    l_cnt := sql%rowcount;

    commit;

    while (l_cnt < l_rows)
    loop
        insert /*+ APPEND */ into bigtab
        select rownum+l_cnt,
               OWNER, OBJECT_NAME, SUBOBJECT_NAME,
               OBJECT_ID, DATA_OBJECT_ID,
               OBJECT_TYPE, CREATED, LAST_DDL_TIME,
               TIMESTAMP, STATUS, TEMPORARY,
               GENERATED, SECONDARY
          from bigtab
         where rownum <= l_rows-l_cnt;
        l_cnt := l_cnt + sql%rowcount;
        commit;
    end loop;
end;
/

alter table bigtab add constraint
bigtab_pk primary key(id);