TOP segmentos, tablas e indices

Con estas consultas podemos ver los segmentos (tablas, indices o ambos) que mayor espacio ocupan en nuestra db o esquema: 

Caso I:

select
   *
from (
   select
      owner,
      segment_name,
      bytes/1024/1024/1024 GB
   from
      dba_segments
   where
      segment_type = 'TABLE'
      and owner = '%USER%'
   order by
      bytes/1024/1024/1024 desc)
where
   rownum <= 10;

Caso II:

select
   *
from (
   select
      owner,
      segment_name,
      bytes/1024/1024/1024 GB
   from
      dba_segments
   where
      segment_type = 'INDEX'
      and owner = '%USER%'
   order by
      bytes/1024/1024/1024 desc)
where
   rownum <= 10;

Caso III:

select
   *
from (
   select
      owner,
      segment_name,
      bytes/1024/1024/1024 GB
   from
      dba_segments
   where
   order by
      bytes/1024/1024/1024 desc)
where
   rownum <= 10;