centos7安装mysql8.0

MySQL 8 正式版 8.0.11 已发布，官方表示 MySQL 8 要比 MySQL 5.7 快 2 倍，还带来了大量的改进和更快的性能！

mysql8.0安装步骤：

1、添加yum安装库

安装库的下载地址：https://repo.mysql.com//mysql80-community-release-el7-2.noarch.rpm

wget https://repo.mysql.com//mysql80-community-release-el7-2.noarch.rpm

rpm -Uvh mysql80-community-release-el7-2.noarch.rpm

2、安装mysql

yum install mysql-community-server

3、MySQL服务器初始化（从MySQL 5.7开始）：在服务器初始启动时，如果服务器的数据目录为空，则会发生以下情况：

服务器已初始化。
在数据目录中生成SSL证书和密钥文件。
该validate_password插件安装并启用。
将‘root‘@‘localhost‘ 创建一个超级用户帐户。设置超级用户的密码并将其存储在错误日志文件中。要显示它，请使用以下命令：
```
shell> sudo grep ‘temporary password‘ /var/log/mysqld.log
```
通过使用生成的临时密码登录并为超级用户帐户设置自定义密码，尽快更改root密码：
```
shell> mysql -uroot -p
```
```
mysql> ALTER USER ‘root‘@‘localhost‘ IDENTIFIED BY ‘MyNewPass4!‘;
```

4、注意密码的强度

MySQL的 validate_password 插件默认安装。这将要求密码包含至少一个大写字母，一个小写字母，一个数字和一个特殊字符，并且密码总长度至少为8个字符。

这个其实与validate_password_policy的值有关, mysql8.0更改了validate_password_policy相关的配置名称, 这跟Mysql5.7有点不一样了.

mysql> set global validate_password.policy=0;

Query OK, 0 rows affected (0.00 sec)

mysql> set global validate_password.length=1;

Query OK, 0 rows affected (0.00 sec)

接着再修改密码

mysql> ALTER USER ‘root‘@‘localhost‘ IDENTIFIED BY ‘123456‘;

Query OK, 0 rows affected (0.05 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.03 sec)

5. Mysql8.0要注意的点

1) 创建用户和授权

在mysql8.0创建用户和授权和之前不太一样了，mysql8.0需要先创建用户和设置密码,然后才能授权。

mysql> create user ‘kevin‘@‘%‘ identified by ‘123456‘;

Query OK, 0 rows affected (0.04 sec)

mysql> grant all privileges on *.* to ‘kevin‘@‘%‘ with grant option;

Query OK, 0 rows affected (0.04 sec)

mysql> create user ‘bobo‘@‘%‘ identified by ‘123456‘;

Query OK, 0 rows affected (0.06 sec)

mysql> grant all privileges on *.* to ‘kevin‘@‘%‘;

Query OK, 0 rows affected (0.03 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.04 sec)

mysql> select host,user,authentication_string from mysql.user;

+-----------+------------------+------------------------------------------------------------------------+

| host | user | authentication_string |

+-----------+------------------+------------------------------------------------------------------------+

| % | bobo | $A$005$1VY")q?G6<^X@-6LsXrPt5C0TwlTuvHbaOa3sYF0DKViIGoRPuCF8AzwiFcim1 |

| % | kevin | $A$005$hy`U}ZB#R::rA8W0y2rmwgySqzv0rmR1eTeNDSaXfQPWIsrh7ytbVdi85 |

| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |

| localhost | mysql.session | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |

| localhost | mysql.sys | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |

| localhost | root | $A$005$/VO_y^7,]6;2qxggBLmJzhA0Qylu5/AHuRScZ/ykKedgZKh/6krOIzPs2 |

+-----------+------------------+------------------------------------------------------------------------+

如果还是用Mysql5.7及之前版本的直接授权的方法, 会有报错:

mysql> grant all privileges on *.* to ‘shibo‘@‘%‘ identified by ‘123456‘;

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘identified by ‘123456‘‘ at line 1

2) Mysql8.0默认是不能使用root账号进行远程登录的! root账号只能本地登录!