探讨:MySQL中如何查询当前正在运行的SQL语句

时间:2021-09-20 02:34:17

通过status命令,查看Slow queries这一项,如果值长时间>0,说明有查询执行时间过长

复制代码代码如下:


以下为引用的内容:
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 
--------------


这时再通过show processlist命令来查看当前正在运行的SQL,从中找出运行慢的SQL语句,找到执行慢的语句后,再用explain命令查看这些语句的执行计划。
mysql> show processlist;
+----+------+-----------+------+---------+------+-------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+-------+------------------+
| 53 | root | localhost | NULL | Query | 0 | NULL | show processlist |
+----+------+-----------+------+---------+------+-------+------------------+