Oracle数据库锁表查询

--查看数据库最大连接数
select value from v$parameter where name = ‘processes‘;
--更改数据库连接数
alter system set processes = 3000 scope = spfile;
--查看被锁的表 
select b.owner,b.object_name,a.session_id,a.locked_mode from v$locked_object a,dba_objects b where b.object_id = a.object_id;
--查看当前活跃线程数
select s.status,s.* from v$session s  where schemaname=‘数据库用户名‘ and machine=‘机器名‘;
select sid,serial#,username,program,machine,status from v$session;
select count(*) from v$session;

--查看sql执行记录
select * from v$sqltext  where sql_text like ‘%sql语句%‘;

--查询锁表语句  
select l.session_id sid, 
       s.serial#, 
       l.locked_mode, 
       l.oracle_username, 
       s.user#, 
       l.os_user_name, 
       s.machine, 
       s.terminal, 
       a.sql_text, 
       a.action 
  from v$sqlarea a, v$session s, v$locked_object l 
where l.session_id = s.sid 
   and s.prev_sql_addr = a.address 
order by sid, s.serial#;

--查看oracle正在执行的任务
select a.program,a.osuser, a.sql_exec_start, b.spid, c.sql_text,c.SQL_ID, c.FIRST_LOAD_TIME, c.last_load_time, c.last_active_time
from v$session a, v$process b, v$sqlarea c
where a.paddr = b.addr
and a.sql_hash_value = c.hash_value
and a.username is not null;

--查出oracle当前的被锁对象
SELECT l.session_id sid,  
       s.serial#,  
       l.locked_mode 锁模式,  
       l.oracle_username 登录用户,  
       l.os_user_name 登录机器用户名,  
       s.machine 机器名,  
       s.terminal 终端用户名,  
       o.object_name 被锁对象名,  
       s.logon_time 登录数据库时间  
FROM v$locked_object l, all_objects o, v$session s  
WHERE l.object_id = o.object_id  
   AND l.session_id = s.sid  
ORDER BY sid, s.serial#;  

SELECT * FROM V$LOCKED_OBJECT l,V$SESSION S WHERE l.SESSION_ID=S.SID;

--杀掉进程 sid,serial#
alter system kill session ‘223,10747‘;

--批量杀死进程
declare cursor mycur is   
select b.sid,b.serial#   
　　from v$locked_object a,v$session b   
　　where a.session_id = b.sid group by b.sid,b.serial#;   
   
begin   
  for cur in mycur   
    loop     
     execute immediate ( ‘alter system  kill session  ‘‘‘||cur.sid || ‘,‘|| cur.SERIAL# ||‘‘‘ ‘);   
     end loop;   
end;