centos7下安装mysql

centos7下安装mysql

配置环节请按实际情况修改

1. 下载并安装MySQL官方的Yum Repository

[root@localhost ~]# wget -i -c https://repo.mysql.com/mysql57-community-release-el7-10.noarch.rpm
http://dev.mysql.com/get/mysql57-community-release-el7-10.noarch.rpm
https://repo.mysql.com/mysql57-community-release-el7-10.noarch.rpm

使用上面的命令直接安装Yum Repository

[root@localhost ~]# yum -y install mysql57-community-release-el7-10.noarch.rpm

安装MySQL服务器

root@localhost ~]# yum -y install mysql-community-server

2. MySQL数据库设置
启动MySQL

[root@localhost ~]# systemctl start  mysqld.service

查看MySQL运行状态

[root@localhost ~]# systemctl status mysqld.service

此时MySQL已经开始正常运行，需要找出root的密码

[root@localhost ~]# grep "password" /var/log/mysqld.log

如下命令登录mysql

# mysql -uroot -p

输入初始密码，此时不能做任何事情，因为MYSQL默认必须修改密码才能正常使用

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'new password';

# 这里会遇到一个问题，新密码设置过于简单会报错123

可通过如下命令查看完整的初始密码规则

mysql>show variables like 'validate_password%';

可通过如下命令修改

mysql> set global validate_password_policy=0;
mysql> set global validate_password_length=1;

还有一个问题就是Yum Repository,以后每次 yum 操作都会自动更新，需要把这个卸载掉

[root@localhost ~]# yum -y remove mysql57-community-release-el7-10.noarch

远程登录数据库出现下面出错信息
ERROR 2003 (HY000): Can’t connect to MySQL server on ‘xxx.xxx.xxx.xxx’,
原因是没有授予相应的权限

#任何主机
mysql>GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '123456' WITH GRANT OPTION;

#指定主机
mysql>GRANT ALL PRIVILEGES ON *.* TO 'jack'@’10.10.50.127’ IDENTIFIED BY '654321' WITH GRANT OPTION;

# 然后刷新权限
mysql>flush privileges;

修改mysql数据库总的user表使相的用户能从某一主机登录

mysql>use mysql;
mysql>update user set host = '%' where user = 'root';
mysql>select host, user from user;

客户端提供MYSQL的环境，但是不支持中文,通过以下命令可以查看mysql的字符集

mysql>show variables like 'character_set%';

显示如下：

为了让 MySQL支持中文，需要把字符集改成UTF-8，方法如下

# vim /etc/my.cnf

改成如下内容

[client]
port=3306
socket=/var/lib/mysql/mysql.sock
default-character-set=utf8

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
character-set-server=utf8

[mysql]
no-auto-rehash
default-character-set=utf8

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

重启mysql服务

# service mysqld restart

重新查看数据库编码

show variables like 'character_set%';