oracle 查看锁表情况及数据库连接情况

--查询表空间名称和大小

SELECT UPPER (F.TABLESPACE_NAME) "表空间名",

D.TOT_GROOTTE_MB "表空间大小(M)",

D.TOT_GROOTTE_MB - F.TOTAL_BYTES "已使用空间(M)",

TO_CHAR (ROUND ((D.TOT_GROOTTE_MB - F.TOTAL_BYTES) / D.TOT_GROOTTE_MB * 100, 2), '990.99') "使用比",

F.TOTAL_BYTES "空闲空间(M)",

F.MAX_BYTES "最大块(M)"

FROM ( SELECT TABLESPACE_NAME,

ROUND (SUM (BYTES) / (1024 * 1024), 2) TOTAL_BYTES,

ROUND (MAX (BYTES) / (1024 * 1024), 2) MAX_BYTES

FROM SYS.DBA_FREE_SPACE

GROUP BY TABLESPACE_NAME) F,

( SELECT DD.TABLESPACE_NAME,

ROUND (SUM (DD.BYTES) / (1024 * 1024), 2) TOT_GROOTTE_MB

FROM SYS.DBA_DATA_FILES DD

GROUP BY DD.TABLESPACE_NAME) D

WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME

ORDER BY 4 DESC;

--查看数据库引起锁表的SQL语句：

SELECT A.USERNAME,

A.MACHINE,

A.PROGRAM,

A.SID,

A.SERIAL#,

A.STATUS,

C.PIECE,

C.SQL_TEXT

FROM V$SESSION A,

V$SQLTEXT C

WHERE A.SID IN (SELECT DISTINCT T2.SID

FROM V$LOCKED_OBJECT T1,

V$SESSION T2

WHERE T1.SESSION_ID = T2.SID)

AND A.SQL_ADDRESS = C.ADDRESS(+)

ORDER BY C.PIECE;

--查看数据库锁的情况必须要有DBA权限，可以使用一下SQL 语句：

SELECT object_id, session_id, locked_mode FROM v$locked_object;

SELECT t2.username,

t2.sid,

t2.serial#,

t2.logon_time

FROM v$locked_object t1, v$session t2

WHERE t1.session_id = t2.sid

ORDER BY t2.logon_time;

--查看被锁的表

SELECT P.SPID,

A.SERIAL#,

C.OBJECT_NAME,

B.SESSION_ID,

B.ORACLE_USERNAME,

B.OS_USER_NAME

FROM V$PROCESS P,

V$SESSION A,

V$LOCKED_OBJECT B,

ALL_OBJECTS C

WHERE P.ADDR = A.PADDR

AND A.PROCESS = B.PROCESS

AND C.OBJECT_ID = B.OBJECT_ID;

--杀掉进程

ALTER SYSTEM KILL SESSION 'sid,serial#';

--查看连接数

SELECT COUNT (*) FROM v$session;

--查看并发连接数

SELECT COUNT(*) FROM V$SESSION WHERE STATUS='ACTIVE';

--查看连接的进程

SELECT SID, SERIAL#, USERNAME, OSUSER FROM V$SESSION;

--查看数据库使用的裸设备

SELECT *

FROM dba_data_files

ORDER BY file_name;

SELECT *

FROM dba_temp_files

ORDER BY file_name;

SELECT *

FROM v$controlfile

ORDER BY file_name;

SELECT *

FROM v$logfile;

--具体的方法是查询dba_data_files，dba_temp_files，v$controlfile和v$logfile看这四类文件具体占用的裸设备

--查询所有用户表使用大小的前三十名

select * from (select segment_name,bytes from dba_segments where owner = USER order by bytes desc ) where rownum <= 30;

--以下的SQL语句列出当前数据库建立的会话情况:

select sid,serial#,username,program,machine,status from v$session;

--如果DBA要手工断开某个会话，则执行:

alter system kill session 'SID,SERIAL#';