SELECT `pe2e_user_to_company`.company_name, `pe2e_user_to_company`.company_code, `users`.name, `users`.uid, `users`.mail, `pe2e_email_notification_email`.`email_cc` FROM `users` , `pe2e_user_to_company` LEFT JOIN `pe2e_email_notification_email` ON `pe2e_user_to_company`.`uid` = `pe2e_email_notification_email`.`uid` WHERE `users`.`uid` = `pe2e_user_to_company`.`uid` into outfile '/tmp/users.csv' fields terminated by ',' enclosed by '"' lines terminated by '\r\n'; 

[root@166087 mysql]# /usr/local/mysql/bin/mysqld_safe --defaults-file=/etc/my.cnf --datadir=/data/mysql --skip-grant-tables

mysql> update user set authentication_string=password('123456') where user='root';

update user set host='%' where user='root' and host='localhost';

flush privileges;    #刷新权限表，使配置生效

use mysql        #打开mysql数据库

update user set host='localhost' where user='root';    #将host设置为localhost表示只能本地连接mysql

flush privileges;    #刷新权限表，使配置生效

update user set password=password('123456') where User='root';#修改密码

flush privileges ; #刷新权限表，使配置生效

grant all on *.* to 'yuancheng'@'%' identified by '123456';

flush privileges;

update t_comment SET avatar = replace(avatar, 'http', 'https');//替换

update t_log set message=concat("https",message);//前面追加