Mysql 优化 - 常用步骤 show processlist

#查看所有连接

show processlist;

 

查看SQL执行计划

explain select * from table;

 

#查看数据库连接数

SELECT SUBSTRING_INDEX(HOST,':',1) AS ip , COUNT(*) FROM information_schema.processlist GROUP BY ip;

 

#查看某台应用连接数据库数

SELECT * FROM information_schema.processlist WHERE HOST LIKE '%192.168.1.122%' and TIME>90;

 

#查看慢SQL

SELECT * FROM mysql.`slow_log` t WHERE user_host LIKE '%192.168.1.122%' ORDER BY t.`query_time` DESC;