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 lockedobjectlo,dbaobjectsao,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 LOCKWHERE(id1,id2,type)IN(SELECTid1,id2,typeFROMGV 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 sessiona,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 sessiona,v process b,v$sesstat c where c.statistic#=12 and c.sid=a.sid and a.paddr=b.addr order by value desc;
6.查看死锁信息 SELECT (SELECT username FROM v sessionWHERESID=a.SID)blocker,a.SID,‘isblocking′,(SELECTusernameFROMv session WHERE SID = b.SID) blockee, b.SID FROM v locka,v lock b WHERE a.BLOCK = 1 AND b.request > 0 AND a.id1 = b.id1 AND a.id2 = b.id2;
7.具有最高等待的对象 SELECT o.OWNER,o.object_name, o.object_type, a.event, SUM (a.wait_time + a.time_waited) total_wait_time FROM v$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 activesessionhistorya,dbaobjectso,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 sesstatS,v statname N,v$session A where n.statistic#=s.statistic# and name=’session pga memory’ and s.sid=a.sid order by s.value;
9.等待最多的用户 SELECT s.SID, s.username, SUM (a.wait_time + a.time_waited) total_wait_time FROM v activesessionhistorya,v session s WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE GROUP BY s.SID, s.username ORDER BY total_wait_time DESC;
10.等待最多的SQL SELECT a.program, a.session_id, a.user_id, d.username, s.sql_text, SUM (a.wait_time + a.time_waited) total_wait_time FROM v activesessionhistorya,v sqlarea s, dba_users d WHERE a.sample_time BETWEEN SYSDATE - 30 / 2880 AND SYSDATE AND a.sql_id = s.sql_id AND a.user_id = d.user_id GROUP BY a.program, a.session_id, a.user_id, s.sql_text, d.username;
11.查看消耗资源最多的SQL SELECT hash_value, executions, buffer_gets, disk_reads, parse_calls FROM V$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 sessiona,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;
