Oracle锁表故障处理一例
一次开发人员直接在数据库服务器上做deletetable操作系统,由时在上班高峰运行,造成长时间执行无反应,进而把SQLPLUS客户端关闭掉,再次运行删除语句,造成数据
一次开发人员直接在数据库服务器上做delete table操作系统,由时在上班高峰运行,造成长时间执行无反应,进而把SQLPLUS客户端关闭掉,再次运行删除语句,造成数据库运行缓慢。
询问操作过程知道了是由锁表造成,,最终处理;本文只是模拟锁表处理过程,下次遇到相同问题可以快速处理。
如果不清楚原因,可以通过先通过等待事件进行分析。
SQL> select sid,EVENT from v$session_wait where wait_class'Idle';
SID EVENT
---------- ----------------------------------------------------------------
158 SQL*Net message to client
159 enq: TX - row lock contention
SQL>
2. 查看数据库是否有锁
SQL> select * from v$lock where block=1;
3. 查询lock锁, 看谁锁谁
说明:BLOCK为1的行,表示资源由它锁定。REQUEST表示需要这个锁。
SQL> SELECT sid, id1, id2, lmode, block,request, type
FROM V$LOCK
WHERE id1 IN (SELECT id1 FROM V$LOCK WHERE lmode = 0)
ORDER BY id1, request;
SID ID1 ID2 LMODE BLOCK REQUEST TY
---------- ---------- ---------- ---------- ---------- ---------- --
153 655397 308 6 1 0 TX
157 655397 308 0 0 6 TX
4. 查询锁表的SID,Serial#,用户、开始时间,然后就可以杀掉该进程了。
SQL> select t1.sid,t1.serial#,t1.username,t1.logon_time from v$session t1,v$locked_object t2 where t1.sid = t2.session_id order by t1.logon_time ;
SID SERIAL# USERNAME LOGON_TIME
---------- ---------- ------------------------------ -------------------
153 12 ABC 2014-11-17 09:19:33
157 106 ABC 2014-11-17 09:54:24
5. 可以进一步查询出SID,SPID等信息
SQL> select s.username, s.osuser, s.sid, s.serial#, p.spid, s.program,s.STATUS
from v$session s,v$process p
where s.paddr = p.addr and s.username is not null;
USERNAME OSUSER SID SERIAL# SPID PROGRAM STATUS
------------------------------ ------------------------------ ---------- ---------- ------------ ------------------------------------------------ --------
ABC oracle 153 12 4290 sqlplus@oradb (TNS V1-V3) INACTIVE
SYS oracle 150 12 4417 sqlplus@oradb (TNS V1-V3) ACTIVE
ABC oracle 157 119 4830 sqlplus@oradb (TNS V1-V3) ACTIVE
要么在oracle进行杀掉,以及在操作系统下杀掉,对于status为killed的语句,应用通过操作系统kill命令才能最终最快杀掉。
alter system kill session '153,12';
alter system kill session '157,119';
或操作系统中
kill -9 4290
kill -9 4830
6. 查询被锁的表的SID及相关资源
说明:出被锁的表及SQL,还是要结合上面的查询进行手工处理, 也可以通过SID找到SQL语句。
set pagesize 999;
set linesize 200;
col PROGRAM for a25;
col TERMINAL for a10;

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