select A.tablespace_name, A.contents, extent_management EM, allocation_type AT,
       decode(allocation_type, 'UNIFORM',next_extent/1024,'') NE,
       B.max_mb, B.curr_mb,
       (B.max_mb - B.curr_mb) + nvl(c.free_mb,0) free_mb,
       ((100/B.max_mb)*(B.max_mb - B.curr_mb + nvl(c.free_mb,0))) pct_free
from dba_tablespaces A,
     ( select tablespace_name, sum(bytes)/1024/1024 curr_mb,
              sum(greatest(bytes, maxbytes))/1024/1024 max_mb
       from dba_data_files
       group by tablespace_name
       union all
       select tablespace_name, sum(bytes)/1024/1024 curr_mb,
              sum(greatest(bytes, maxbytes))/1024/1024 max_mb
       from dba_temp_files
       group by tablespace_name
     ) B,
     ( select tablespace_name, sum(bytes)/1024/1024 free_mb
       from dba_free_space
       group by tablespace_name
     ) C
where A.tablespace_name = B.tablespace_name
      and A.tablespace_name = C.tablespace_name(+)
order by tablespace_name
/