dirkgomez.de

select substr( a.file_name, 
  instr(a.file_name,'/',-1)) file_name, 
  round(bytes/1024/1024) mBytes, 
  round(nvl(b.free,0)/1024/1024) Free, 
  round( (a.bytes-nvl(b.free,0))/1024/1024) used 
  from dba_data_files a, 
  (select sum(bytes) free, file_id 
  from dba_free_space 
    group by file_id ) b 
    where a.file_id = b.file_id(+); 

select FS.tablespace_name, File_Name, SUM(FS.Blocks) as remaining, DF.Blocks as total_space, SUM(FS.bytes), maxextend*8192, inc*8192 
  from   DBA_FREE_SPACE FS, DBA_DATA_FILES DF, SYS.FILEXT$ 
  where 
    FS.File_Id = DF.File_id and FS.File_id=File#(+) 
    group by FS.tablespace_name, File_Name, DF.Blocks, maxextend, inc 
    order by FS.tablespace_name, File_Name