oracle查询表空间

select *
FROM
(select tablespace_name, sum(bytes/1024/1024) Free_Space
from sys.dba_free_space
group by tablespace_name
) Free,
(select b.name, sum(bytes/1024/1024) TOTAL_SPACE,a.NAME as filepath
from sys.v_$datafile a, sys.v_$tablespace B
where a.ts# = b.ts#
group by b.name,a.NAME
) Total
WHERE Free.Tablespace_name = Total.name