Next_extent no cabe en tablespace (dict or local).

set lines 500
set pages 1000
set trimout on
set trimspool on
select x.tablespace_name, x.owner, x.segment_type, x.segment_name, (x.next_extent-x.maximo_libre)/&M deficit
from (
      select t.tablespace_name, s.owner, s.segment_type, s.segment_name,
           decode(t.extent_management,
                   'LOCAL',
                   decode(t.allocation_type,
                        'SYSTEM',
                        case when s.extents < 16 then 65536          -- 64K
                             when s.extents < 79 then 1048576        --  1M
                             when s.extents < 199 then 8388608       --  8M
                             else 67108864                           -- 64M
                        end,
                        s.next_extent
                   ),
                   s.next_extent
           ) next_extent,
           nvl(f.maximo_libre,0) maximo_libre
      from dba_tablespaces t,
           (
                select /*+ RULE */ tablespace_name, owner, segment_type, segment_name, extents, next_extent
                from dba_segments
           ) s,
           (
                select /*+ RULE */ tablespace_name, max(bytes) maximo_libre
                from dba_free_space
                group by tablespace_name
           ) f
      where t.tablespace_name = s.tablespace_name and t.tablespace_name = f.tablespace_name
      order by next_extent
      ) x
where x.next_extent > x.maximo_libre;