Oracle故障排查之oracle解决锁表问题

--step 1：查看被阻塞会话等待事件

select sid, event, username, lockwait, sql.sql_text
  from v$session s, v$sql sql
where s.sql_id = sql.sql_id
   and sql.sql_text like '%&sql%';

-------------------------------------------------------------------------
    22    enq: TX - row lock contention    SCOTT    000000007F8C4DD8    update emp set ename='dbking' where empno=7369
    23    enq: TX - row lock contention    SCOTT    000000007F8C4F98    delete from emp where empno=7499

--step 2：查找阻塞的blocker

select sid, inst_id, blocking_instance, blocking_session
  from gv$session
where sid = 22;

-----------------------------------------------------------------------
    22    1    1    142

或

select sid, inst_id, blocking_instance, blocking_session
  from gv$session
where sid in (22, 23);

----------------------------------

22    1    1    142
23    1    1    142

--step 3：清除blocker

确认要清除会话的sid和serial#：

select sid, serial#
  from gv$session
where inst_id = 1
   and sid = 142;

--------------------------------------
    142    873

清除会话：

SQL> alter system kill session '142,873';

System altered.

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select sql_text
  from v$sqltext a
where (a.hash_value, a.address) in
       (select decode(sql_hash_value, 0, prev_hash_value, sql_hash_value),
               decode(sql_hash_value, 0, prev_sql_addr, sql_address)
          from v$session b
         where b.paddr = (select addr from v$process c where c.pid = '&pid'))
order by piece asc;