2018-06-07-检查sql语句占用多大内存和耗时

检查sql语句占用多大内存和耗时；

主要是用到information_schema库

命令：select p.user,p.host,p.ID,p.memory_used,t.trx_started,p.INFO from information_schema.processlist as p inner join information_schema.innodb_trx as t on t.trx_mysql_thread_id=p.ID order by t.trx_started desc limit 10 ;

检查目前系统打开了哪些表

show open tables;

检查innodb引擎目前问题点在哪

show engine innodb status;