Oracle view tablespace usage

oracle Check tablespace usage

SELECT Upper(F.TABLESPACE_NAME)         " Table space name ",
       D.TOT_GROOTTE_MB                 " Table space size (M)",
       D.TOT_GROOTTE_MB - F.TOTAL_BYTES " Used space (M)",
       To_char(Round(( D.TOT_GROOTTE_MB - F.TOTAL_BYTES ) / D.TOT_GROOTTE_MB * 100, 2), '990.99')
       || '%'                           " Use than ",
       F.TOTAL_BYTES                    " Free space (M)",
       F.MAX_BYTES                      " The most massive (M)"
FROM   (SELECT TABLESPACE_NAME,
               Round(Sum(BYTES) / ( 1024 * 1024 ), 2) TOTAL_BYTES,
               Round(Max(BYTES) / ( 1024 * 1024 ), 2) MAX_BYTES
        FROM   SYS.DBA_FREE_SPACE
        GROUP  BY TABLESPACE_NAME) F,
       (SELECT DD.TABLESPACE_NAME,
               Round(Sum(DD.BYTES) / ( 1024 * 1024 ), 2) TOT_GROOTTE_MB
        FROM   SYS.DBA_DATA_FILES DD
        GROUP  BY DD.TABLESPACE_NAME) D
WHERE  D.TABLESPACE_NAME = F.TABLESPACE_NAME;