mysql查看正在执行的sql

在开发的过程中，我们经常需要查看一下当前数据库的执行情况，比如如果我们select一个数据，很长时间都没有返回，我们在想，是不是什么sql语句把表锁着了，或者什么sql把资源占完了，那么我们怎么查这条sql呢？

办法肯定是有的：

show full processlist

mysql> show full processlist;

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

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

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

| 25 | tuan_sql | 192.168.100.39:60161 | tao800 | Sleep | 18 | | NULL |

| 12196 | tuan_sql | 192.168.100.39:34410 | tao800 | Sleep | 89 | | NULL |

| 13067 | tuan_sql | 192.168.100.39:40964 | tao800 | Sleep | 123 | | NULL |

| 13158 | tuan_sql | 192.168.100.39:41496 | zhe_oem | Sleep | 3213 | | NULL |

| 13181 | tuan_sql | 192.168.100.39:41574 | tao800 | Sleep | 86 | | NULL |

| 13620 | tuan_sql | 192.168.100.39:44335 | tao800 | Sleep | 1 | | NULL |

| 13795 | tuan_sql | 192.168.100.39:45502 | tao800 | Sleep | 261 | | NULL |

| 14961 | tuan_sql | 192.168.100.39:55012 | tao800 | Sleep | 46 | | NULL |

| 15244 | tuan_sql | 192.168.100.39:57875 | tao800 | Sleep | 122 | | NULL |

| 15305 | tuan_sql | 192.168.100.39:58398 | zhe800_lottery | Sleep | 2705 | | NULL |

| 15306 | tuan_sql | 192.168.100.39:58399 | zhe800_lottery | Sleep | 2723 | | NULL |

| 15334 | tuan_sql | 192.168.100.39:58712 | tao800 | Sleep | 2151 | | NULL |

| 15422 | tuan_sql | 192.168.100.39:59571 | tao800 | Sleep | 27 | | NULL |

| 15434 | tuan_sql | 192.168.100.39:59633 | tao800 | Sleep | 18 | | NULL |

| 15521 | tuan_sql | 192.168.100.39:60435 | tao800 | Sleep | 1671 | | NULL |

| 15598 | tuan_sql | 192.168.100.39:32768 | tao800 | Sleep | 1151 | | NULL |

| 15661 | tuan_sql | 192.168.100.39:33489 | tao800 | Sleep | 643 | | NULL |

| 15677 | tuan_sql | 192.168.100.39:33663 | tao800 | Sleep | 264 | | NULL |

| 15682 | tuan_sql | 192.168.100.39:33716 | tao800 | Sleep | 264 | | NULL |

| 15690 | tuan_sql | 192.168.100.39:33791 | tao800 | Query | 0 | NULL | show full processlist |

| 15707 | tuan_sql | 192.168.100.39:34000 | zhe_oem | Sleep | 285 | | NULL |

| 15708 | tuan_sql | 192.168.100.39:34002 | zhe_oem | Sleep | 285 | | NULL |

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

22 rows in set (0.00 sec)

我们详细介绍一下每个属性是什么意思吧

id

很容易就猜到是这个连接的id，值对应这个连接使用的线程id。

User

用户名

Host

连接的地址和端口，那么你可能会问，为什么我贴的例子的地址都是同一个host呢，很明显是用了代理，感兴趣的可以看看这篇文章http://www.phpv.net/html/1583.html，这里就不详细解释了。

db

此连接所连接使用的数据库名。

command

一般有俩值：sleep和query，从字面意思就可以看出，一个是处理睡眠状态，就是处于连接状态，但是没有正在执行任何sql语句，Query代表正在执行sql语句。

Time

连接的时间。

State

我个人觉得应该是当前线程的状态吧。

info

代表正在执行的sql，如果command为sleep时，它为空。

那如果我们遇到一个sql要执行很长时间，但是我们又不想让它继续执行了，怎么办呢？既然每个连接是在一个线程里维护，这个线程是否可以删除呢？我们尝试一下：

mysql> show full processlist;
+-------+----------+----------------------+---------+---------+------+-------+-----------------------+
| Id    | User     | Host                 | db      | Command | Time | State | Info                  |
+-------+----------+----------------------+---------+---------+------+-------+-----------------------+
|    25 | tuan_sql | 192.168.100.39:60161 | tao800  | Sleep   |    2 |       | NULL                  |
| 12196 | tuan_sql | 192.168.100.39:34410 | tao800  | Sleep   |   43 |       | NULL                  |
| 13067 | tuan_sql | 192.168.100.39:40964 | tao800  | Sleep   |   77 |       | NULL                  |
| 13181 | tuan_sql | 192.168.100.39:41574 | tao800  | Sleep   |   69 |       | NULL                  |
| 13620 | tuan_sql | 192.168.100.39:44335 | tao800  | Sleep   |    2 |       | NULL                  |
| 13795 | tuan_sql | 192.168.100.39:45502 | tao800  | Sleep   |  215 |       | NULL                  |
| 14961 | tuan_sql | 192.168.100.39:55012 | tao800  | Sleep   |    0 |       | NULL                  |
| 15244 | tuan_sql | 192.168.100.39:57875 | tao800  | Sleep   |   76 |       | NULL                  |
| 15334 | tuan_sql | 192.168.100.39:58712 | tao800  | Sleep   | 3305 |       | NULL                  |
| 15422 | tuan_sql | 192.168.100.39:59571 | tao800  | Sleep   |  281 |       | NULL                  |
| 15434 | tuan_sql | 192.168.100.39:59633 | tao800  | Sleep   |  272 |       | NULL                  |
| 15521 | tuan_sql | 192.168.100.39:60435 | tao800  | Sleep   | 2825 |       | NULL                  |
| 15598 | tuan_sql | 192.168.100.39:32768 | tao800  | Sleep   | 2305 |       | NULL                  |
| 15690 | tuan_sql | 192.168.100.39:33791 | tao800  | Query   |    0 | NULL  | show full processlist |
| 15813 | tuan_sql | 192.168.100.39:35257 | zhe_oem | Sleep   |  239 |       | NULL                  |
| 15814 | tuan_sql | 192.168.100.39:35258 | zhe_oem | Sleep   |  239 |       | NULL                  |
+-------+----------+----------------------+---------+---------+------+-------+-----------------------+
16 rows in set (0.00 sec)

我们杀掉15814这个线程：

mysql> kill 15814;
Query OK, 0 rows affected (0.00 sec)

哈哈，还是可以的。