ORACLE 表空间使用率查询

SELECT A.TABLESPACE_NAME,
A.BYTES / (1024 * 1024 * 1024 ) TOTAL,
B.BYTES / (1024 * 1024 * 1024 ) USED,
C.BYTES / (1024 * 1024 * 1024 ) FREE,
(B.BYTES * 100 ) / A.BYTES "% USED",
(C.BYTES * 100 ) / A.BYTES "% FREE"
FROM SYS.SM$TS_AVAIL A, SYS.SM$TS_USED B, SYS.SM$TS_FREE C
WHERE A.TABLESPACE_NAME = B.TABLESPACE_NAME
AND A.TABLESPACE_NAME = C.TABLESPACE_NAME;