--查看日志文件

select member from v$logfile;

--查看表空间使用情况

SELECT SUM(bytes) / (1024 * 1024) AS free_space, tablespace_name 
FROM dba_free_space 
GROUP BY
tablespace_name; 
SELECT
a.tablespace_name, 
a.bytes total, 
b.bytes used, 
c.bytes 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; 
--查看回滚段名称及大小

SELECT segment_name, 
tablespace_name, 
r.status, 
(initial_extent /
1024) initialextent, 
(next_extent /
1024) nextextent, 
max_extents, 
v.curext curextent 
FROM
dba_rollback_segs r, v$rollstat v 
WHERE r.segment_id
= v.usn(+) 
ORDER BY
segment_name;