analyze TABLE SCHEMA.TABLE_NAME compute statistics;
SELECT owner,
table_name,
ROUND((num_rows*avg_row_len)) BYTE,
ROUND((num_rows*avg_row_len)/1024) KB,
ROUND((num_rows*avg_row_len)/(1024*1024)) MB
FROM all_tables
WHERE owner = 'SCHEMA' -- Exclude system tables.
AND table_name IN ('TABLE_NAME')
ORDER BY MB DESC;

 

 

SELECT
    FS.TABLESPACE_NAME "TABLESPACE" ,
    (
        DF.TOTALSPACE - FS.FREESPACE
    ) "USED MB" ,
    FS.FREESPACE "FREE MB" ,
    DF.TOTALSPACE "TOTAL MB" ,
    ROUND( 100 *( FS.FREESPACE / DF.TOTALSPACE ) ) "PCT. FREE"
FROM
    (
        SELECT
            TABLESPACE_NAME ,
            ROUND( SUM( BYTES ) / 1048576 ) TOTALSPACE
        FROM
            DBA_DATA_FILES
        GROUP BY
            TABLESPACE_NAME
    ) DF ,
    (
        SELECT
            TABLESPACE_NAME ,
            ROUND( SUM( BYTES ) / 1048576 ) FREESPACE
        FROM
            DBA_FREE_SPACE
        GROUP BY
            TABLESPACE_NAME
    ) FS
WHERE
    DF.TABLESPACE_NAME = FS.TABLESPACE_NAME
    AND DF.TABLESPACE_NAME IN(
        'NAME1' ,
        'NAME2'
    )