1.查看慢查询变量 ``` show variables like '%long%'; ``` 2.查询mysql运行多久命令 ``` show status like 'uptime'; ``` 3.查询启动mysql后多少条查询语句 ``` show status like 'com_Select'; ``` 4.查看当前连接数 ``` show status like 'connections' ``` 5.设置慢查询时间 ``` set long_query_time = 秒为单位; ``` 6.安全启动mysql 打开慢查询记录