install mysql on centos

wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm

rpm -ivh mysql-community-release-el7-5.noarch.rpm

yum install mysql-community-server
 
service mysqld restart

# mysql -u root

mysql> set password for 'root'@'localhost' = password('mypasswd');

或者：ALTER user 'root'@'localhost' IDENTIFIED BY 'mypasswd'

mysql> exit
-----------------------------------------

如果忘了初始密码，

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

可以在日志文件中找到初始密码：

grep 'temporary password' /var/log/mysqld.log

然后修改登录mysql并修改root密码：

ALTER user 'root'@'localhost' IDENTIFIED BY 'XXXXXX';

update mysql.user set host='%' where user ='root';

ALTER user 'root'@'%' IDENTIFIED BY 'XXXXXX';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'WITH GRANT OPTION;
FLUSH PRIVILEGES;

--mysql8.0要修改密码加密规则

update mysql.user set plugin='mysql_native_password', authentication_string='' where user='root';
ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'XXXXXX';

重启MySQL

service mysqld restart

防火墙开放端口：
firewall-cmd --permanent --zone=public --add-port=3306/tcp
firewall-cmd --reload

 ---------------------------------------

修改mysql默认字符集

1、  处理mysql的字符集，通过show variables like 'character%';命令确认。

vim /etc/my.cnf

[mysqld]

character-set-server=utf8

default-time-zone='+08:00'

[mysql]

default-character-set=utf8

然后重启mysql：service mysqld restart