SELECT file_name, file_id, tablespace_name, online_status FROM dba_data_files;
SELECT file#, ts#, name, status FROM v$datafile;
SELECT group#, status, type, member FROM v$logfile;
SELECT ts#, name FROM v$tablespace;
SELECT file#, ts#, status, error, tablespace_name, name FROM v$datafile_header;

SELECT d.file#, h.tablespace_name, d.name, h.error, d.status, h.status 
FROM v$datafile d, v$datafile_header h 
WHERE d.file# = h.file#;

SELECT v$tablespace.name, v$datafile.name 
FROM v$tablespace, v$datafile 
WHERE v$tablespace.TS# = v$datafile.TS#;

SELECT  b.file_name "FILE_NAME",
                 b.tablespace_name "TABLESPACE_NAME",
                 b.bytes / 1024 "TOTAL SIZE(KB)",
                 ((b.bytes - sum(nvl(a.bytes,0)))) "USED",
                 (sum(nvl(a.bytes,0)))  "FREE SIZE",
                 (sum(nvl(a.bytes,0)) / (b.bytes)) * 100 "FREE %"
         FROM    DBA_FREE_SPACE a, DBA_DATA_FILES b
         WHERE a.file_id(+) = b.file_id
  and b.tablespace_name = 'KMU_WEB_DATA'
         GROUP BY b.tablespace_name, b.file_name, b.bytes
         ORDER BY b.tablespace_name;