查询Oracle相关锁语句
1.查找当前表级锁的SQL如下：
select sess.sid,
sess.serial#,
lo.oracle_username,
lo.os_user_name,
ao.object_name,
lo.locked_mode
from v$locked_object lo,
dba_objects ao,
v$session sess
where ao.object_id = lo.object_id and lo.session_id = sess.sid;
2.杀掉锁表进程：
alter system kill session '436,35123';
3.RAC环境中锁查找：
SELECT inst_id,DECODE(request,0,'Holder: ','Waiter: ')||sid sess,
id1, id2, lmode, request, type,block,ctime
FROM GV$LOCK
WHERE (id1, id2, type) IN
(SELECT id1, id2, type FROM GV$LOCK WHERE request>0)
ORDER BY id1, request;
4.监控当前数据库谁在运行什么SQL语句
select osuser, username, sql_text
from v$session a, v$sqltext b
where a.sql_address =b.address order by address, piece;
5.找使用CPU多的用户session
select a.sid,spid,status,substr(a.program,1,40) prog, a.terminal,osuser,value/60/100 value
from v$session a,v$process b,v$sesstat c
where c.statistic#=12 and
c.sid=a.sid and
a.paddr=b.addr
order by value desc;
6.查看死锁信息
SELECT (SELECT username
FROM v$session
WHERE SID = a.SID) blocker, a.SID, 'is blocking',
(SELECT username
FROM v$session
WHERE SID = b.SID) blockee, b.SID
FROM v$lock a, v$lock b
WHERE a.BLOCK = 1 AND b.request > 0 AND a.id1 = b.id1 AND a.id2 = b.id2;
7.具有最高等待的对象
SELECT o.OWNER,o.object_name, o.object_type, a.event,
SUM (a.wait_time + a.time_waited) total_wait_time
FROM v$active_session_history a, dba_objects o
WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE
AND a.current_obj# = o.object_id
GROUP BY o.OWNER,o.object_name, o.object_type, a.event
ORDER BY total_wait_time DESC;
SELECT a.session_id, s.osuser, s.machine, s.program, o.owner, o.object_name,
o.object_type, a.event,
SUM (a.wait_time + a.time_waited) total_wait_time
FROM v$active_session_history a, dba_objects o, v$session s
WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE
AND a.current_obj# = o.object_id
AND a.session_id = s.SID
GROUP BY o.owner,
o.object_name,
o.object_type,
a.event,
a.session_id,
s.program,
s.machine,
s.osuser
ORDER BY total_wait_time DESC;
8.查询当前连接会话数
select s.value,s.sid,a.username
from
v$sesstat S,v$statname N,v$session A
where
n.statistic#=s.statistic# and
name='session pga memory'
and s.sid=a.sid
order by s.value;
9.等待最多的用户
SELECT s.SID, s.username, SUM (a.wait_time + a.time_waited) total_wait_time
FROM v$active_session_history a, v$session s
WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE
GROUP BY s.SID, s.username
ORDER BY total_wait_time DESC;
10.等待最多的SQL
SELECT a.program, a.session_id, a.user_id, d.username, s.sql_text,
SUM (a.wait_time + a.time_waited) total_wait_time
FROM v$active_session_history a, v$sqlarea s, dba_users d
WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE
AND a.sql_id = s.sql_id
AND a.user_id = d.user_id
GROUP BY a.program, a.session_id, a.user_id, s.sql_text, d.username;
11.查看消耗资源最多的SQL
SELECT hash_value, executions, buffer_gets, disk_reads, parse_calls
FROM V$SQLAREA
WHERE buffer_gets > 10000000 OR disk_reads > 1000000
ORDER BY buffer_gets + 100 * disk_reads DESC;
12.查看某条SQL语句的资源消耗
SELECT hash_value, buffer_gets, disk_reads, executions, parse_calls
FROM V$SQLAREA
WHERE hash_Value = 228801498 AND address = hextoraw('CBD8E4B0');
13.查询会话执行的实际SQL
SELECT a.SID, a.username, s.sql_text
FROM v$session a, v$sqltext s
WHERE a.sql_address = s.address
AND a.sql_hash_value = s.hash_value
AND a.status = 'ACTIVE'
ORDER BY a.username, a.SID, s.piece;
14.显示正在等待锁的所有会话
SELECT * FROM DBA_WAITERS;