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安装过程 及 修改配置

rpm -ivh MySQL-server-5.5.59-1.el7.x86_64.rpm MySQL-client-5.5.59-1.el7.x86_64.rpm
cp /usr/share/mysql/my-medium.cnf /etc/my.cnf
修改 port = 3358
service mysql start
/usr/bin/mysqladmin -u root password 'root'
mysql> set global max_allowed_packet=1024*1024*16;
mysql> use mysql;
mysql> grant all privileges on *.* to 'root'@'%' identified by 'password'; // root访问授权,注意这里的密码和控制台密码可以不一致
mysql> delete from user where host="127.0.0.1";
mysql> flush privileges;
mysql> exit;
service mysql restart

mysql事件

1. 每5秒执行删除表中gmt_create超过12小时的数据

CREATE EVENT e_delete_record ON SCHEDULE EVERY 5 SECOND DO delete from record where gmt_create<(CURRENT_TIMESTAMP()-INTERVAL 12 HOUR);  
alter event e_delete_record on completion preserve enable;