据库都有哪些锁 然后 Kill session
当某个数据库用户在数据库中插入、更新、删除一个表的数据,或者增加一个表的主键时或者表的索引时,常常会出现ora-00054:resource busy and acquire with nowait specified这样的错误。
主要是因为有事务正在执行(或者事务已经被锁),所有导致执行不成功。
1、用dba权限的用户查看数据库都有哪些锁
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;
如:testuser 339 13545 2009-3-5 17:40:05
知道被锁的用户testuser,sid为339,serial#为13545
2、根据sid查看具体的sql语句,如果sql不重要,可以kill
select sql_text from v$session a,v$sqltext_with_newlines b
where DECODE(a.sql_hash_value, 0, prev_hash_value, sql_hash_value)=b.hash_value
and a.sid=&sid order by piece;
查出来的sql,如: begin :id := sys.dbms_transaction.local_transaction_id; end;
3、kill该事务
alter system kill session '339,13545';
dba 查锁表
SELECT OBJECT_NAME,
MACHINE,
S.SID,
S.SERIAL#,
L.OS_USER_NAME,
S.SQL_EXEC_START
FROM V$LOCKED_OBJECT L, DBA_OBJECTS O, V$SESSION S
WHERE L.OBJECT_ID = O.OBJECT_ID
AND L.SESSION_ID = S.SID;
--alter system kill session 'sid,serial' ;
4、查询正在执行的sql
SELECT 'alter system kill session ' || '''' || s.sid || ',' || s.serial# || ''';',
s.SQL_EXEC_START,
username,
osuser,
disk_reads,
buffer_gets,
executions,
-- ROUND(buffer_gets / executions, 2) AVG2,
sorts,
sql_FULLTEXT AS sql_text
FROM v$session s, v$sqlarea a
WHERE s.sql_address = a.address
AND s.sql_hash_value = a.hash_value
AND status = 'ACTIVE'
AND TYPE != 'BACKGROUND';