Tablespace usage

set pages 999
col tablespace_name format a40
col "size MB" format 999,999,999
col "free MB" format 99,999,999
col "% Used" format 999
select  tsu.tablespace_name, ceil(tsu.used_mb) "size MB"
, decode(ceil(tsf.free_mb), NULL,0,ceil(tsf.free_mb)) "free MB"
, decode(100 - ceil(tsf.free_mb/tsu.used_mb*100), NULL, 100,
               100 - ceil(tsf.free_mb/tsu.used_mb*100)) "% used"
from (select tablespace_name, sum(bytes)/1024/1024 used_mb
 from  dba_data_files group by tablespace_name union all
 select  tablespace_name || '  **TEMP**'
 , sum(bytes)/1024/1024 used_mb
 from  dba_temp_files group by tablespace_name) tsu
, (select tablespace_name, sum(bytes)/1024/1024 free_mb
 from  dba_free_space group by tablespace_name) tsf
where tsu.tablespace_name = tsf.tablespace_name (+)
order by 4
/