postgresql 查看系统中的锁信息与锁资源

http://blog.csdn.net/rudygao/article/details/49334001

SELECT locker.pid,  
        pc.relname,  
        locker.mode,  
        locker_act.application_name,  
        least(query_start,xact_start) start_time,  
        locker_act.state,  
        CASE  
    WHEN granted='f' THEN  
    'wait_lock'  
    WHEN granted='t' THEN  
    'get_lock'  
    END lock_satus,current_timestamp - least(query_start,xact_start) AS runtime,  
    locker_act.query  
FROM pg_locks locker,pg_stat_activity locker_act, pg_class pc  
WHERE locker.pid=locker_act.pid  
        AND NOT locker.pid=pg_backend_pid()  
        AND application_name<>'pg_statsinfod'  
        AND locker.relation = pc.oid  
        AND pc.reltype<>0 --and pc.relname='t'  
ORDER BY  runtime desc; 

kill有两种方式，第一种是：
SELECT pg_cancel_backend(PID);
这种方式只能kill select查询，对update、delete 及DML不生效)

第二种是：
SELECT pg_terminate_backend(PID);
这种可以kill掉各种操作(select、update、delete、drop等)操作