查看表空间的使用情况

SELECT c.tablespace_name tablespace_name, ROUND(a.bytes/1048576,2) total_size,ROUND((a.bytes-b.bytes)/1048576,2) used_size,
ROUND(b.bytes/1048576,2) free_size,
ROUND(b.bytes/a.bytes * 100,2)||'%' free_pct FROM
(SELECT tablespace_name,SUM(a.bytes) bytes
FROM sys.DBA_DATA_FILES a
GROUP BY tablespace_name) a,
(SELECT a.tablespace_name,
NVL(SUM(b.bytes),0) bytes
FROM sys.DBA_DATA_FILES a,
sys.DBA_FREE_SPACE b
WHERE a.tablespace_name = b.tablespace_name (+)
AND a.file_id = b.file_id (+)
GROUP BY a.tablespace_name) b, sys.DBA_TABLESPACES c WHERE a.tablespace_name = b.tablespace_name(+)
AND a.tablespace_name = c.tablespace_name
ORDER BY ROUND(b.bytes/1048576,2);