常用的檢視資料庫的SQL

1、檢視錶空間的名稱及大小
　　select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
from dba_tablespaces t, dba_data_files d
where t.tablespace_name = d.tablespace_name
group by t.tablespace_name;
2、檢視錶空間物理檔案的名稱及大小
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;
3、檢視回滾段名稱及大小
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$rollstat v
Where r.segment_id = v.usn(+)
order by segment_name ;
4、檢視控制檔案
select name from v$controlfile;
5、檢視日誌檔案
select member from v$logfile;
6、檢視錶空間的使用情況
select sum(bytes)/(1024*1024) as free_space,tablespace_name
from dba_free_space
group by tablespace_name;
SELECT A.TABLESPACE_NAME,A.BYTES TOTAL,B.BYTES USED, C.BYTES FREE,
(B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
FROM SYS.SM$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;
7、檢視庫物件
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
8、檢視的版本　
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
9、檢視的建立日期和歸檔方式
Select Created, Log_Mode, Log_Mode From V$Database;