Oracle 数据库的锁排查方法
关键字
oracle lock
问题描述
Oracle 数据库上锁问题如何排查
解决问题思路
准备数据
create table lock_test(name varchar(10),age varchar(10));
insert into lock_test values('ff','10');
insert into lock_test values('yy','20');
insert into lock_test values('ll','30');
Oracle 会话默认开启事务:
session1:
update lock_test set age = 'session1' where name = 'ff';
session2:
update lock_test set age = 'session2' where name = 'ff';
session2 因为更新同一行数据肯定 pending
-- 查新活跃会话
select s.sid,
s.sql_id,
s.SQL_CHILD_NUMBER CHILD,
s.USERNAME,s.CLIENT_INFO,
s.LOGON_TIME,
s.EVENT,
s.BLOCKING_SESSION BLOCK,
v.SQL_TEXT
from V$SQL v right join v$session s on v.sql_id=s.sql_id
where s.WAIT_CLASS<>'Idle'
group by s.sid,s.sql_id,s.SQL_CHILD_NUMBER,s.USERNAME,s.CLIENT_INFO,s.LOGON_TIME,s.EVENT,s.BLOCKING_SESSION,v.SQL_TEXT;
|SID|SQL_ID |CHILD|USERNAME|CLIENT_INFO|LOGON_TIME |EVENT |BLOCK|SQL_TEXT |
|---|-------------|-----|--------|-----------|-----------------------|-----------------------------|-----|-----------------------------------------------------------
|8 |5cnbp94b459wf|0 |ADMIN | |2023-09-22 09:47:44.000|enq: TX - row lock contention|1,837|update lock_test set age = 'session2' where name = 'ff' |
-- 查看正在锁的会话
SELECT * FROM V$SESSION_BLOCKERS;
SELECT * FROM V$SESSION_BLOCKERS WHERE BLOCKER_SID NOT IN (SELECT SID FROM V$SESSION_BLOCKERS);
|SID|SESS_SERIAL#|WAIT_ID|WAIT_EVENT|WAIT_EVENT_TEXT |BLOCKER_INSTANCE_ID|BLOCKER_SID|BLOCKER_SESS_SERIAL#|CON_ID|
|---|------------|-------|----------|-----------------------------|-------------------|-----------|--------------------|------|
|8 |59,610 |43 |307 |enq: TX - row lock contention|1 |1,837 |43,494 |0 |
-- 杀掉SESSION
SELECT DISTINCT 'ALTER SYSTEM KILL SESSION ''' || a.BLOCKER_SID || ',' ||a."BLOCKER_SESS_SERIAL#" || ''';' FROM V$SESSION_BLOCKERS a ;
|'ALTERSYSTEMKILLSESSION'''||A.BLOCKER_SID||','||A."BLOCKER_SESS_SERIAL#"||''';'|
|-------------------------------------------------------------------------------|
|ALTER SYSTEM KILL SESSION '1837,43494'; |
模拟二
session1:
update lock_test set age = 'session1' where name = 'ff';
session2:
alter table lock_test add name1 varchar(100);
以上方法可以查询处理
问题总结
Oracle 数据库的锁排查方法