Tablespace Free size for E-business suite


I have included only those tablespaces which frequently become full

select
  a.tablespace_name,
  round(sum(a.bytes/1024/1024),2) TOTAL_MB,  
  round(sum
  (
    ( case
    when autoextensible = 'YES' then
    (a.maxbytes - a.user_bytes) + nvl(b.bytes,0)
    when autoextensible = 'NO' then
    nvl(b.bytes,0)
    end
    )/1024/1024
  ),2) FREE_MB
from
  dba_data_files a,
  (
    select file_id,
      sum(bytes) bytes
    from dba_free_space
    group by file_id
  ) b
where
  a.file_id = b.file_id(+)
and a.tablespace_name in
(
'SYSTEM',
'APPLSYSD',
'APPLSYSX',
'GLX',
'GLD',
'APD',
'APX',
'ARD',
'ARX',
'UNDOTS1'
)
group by a.tablespace_name