本文講解了在MySql中查詢當前正在運行的SQL語句的方法，具體是通過status命令，查看Slow queries這一項，如果值長時間>0,說明有查詢執行時間過長

以下為引用的內容：

MySQL> status;

--------------
        mysql Ver 11.18 Distrib 3.23.58, for redhat-Linux-gnu (i386) 
        Connection id: 53 
        Current database: (null) 
        Current user: root@localhost 
        Current pager: stdout 
        Using outfile: ’’ 
        Server version: 5.0.37-log 
        Protocol version: 10 
        Connection: Localhost via Unix socket 
        Client characterset: latin1 
        Server characterset: latin1 
        UNIX socket: /tmp/mysql.sock 
        Uptime: 4 days 16 hours 49 min 57 sec 
        Threads: 1 Questions: 706 Slow queries: 0 Opens: 177 Flush tables: 1 Open tables:

52 Queries per second avg: 0.002

-------------- 

這時再通過show processlist命令來查看當前正在運行的SQL，從中找出運行慢的SQL語句，找到執行慢的語句后，再用explain命令查看這些語句的執行計劃。

mysql> show processlist;

+----+------+-----------+------+---------+------+-------+------------------+

| Id | User | Host | db | Command | Time | State | Info |

+----+------+-----------+------+---------+------+-------+------------------+

| 53 | root | localhost | NULL | Query | 0 | NULL | show processlist |

+----+------+-----------+------+---------+------+-------+------------------+