CentOS7 yum方式在線安裝MySQL5.7及設置密碼

1.之前安裝了5.6，先卸載了

[root@chen ~]# rpm -qa|grep -i mysql
mysql-community-libs-5.6.48-2.el7.x86_64
mysql-community-release-el7-5.noarch
mysql-community-common-5.6.48-2.el7.x86_64
mysql-community-client-5.6.48-2.el7.x86_64
mysql-community-server-5.6.48-2.el7.x86_64
[root@chen ~]# systemctl stop mysqld.service
[root@chen ~]# rpm -ev --nodeps mysql-community-libs-5.6.48-2.el7.x86_64
Preparing packages...
mysql-community-libs-5.6.48-2.el7.x86_64
[root@chen ~]# rpm -ev --nodeps mysql-community-release-el7-5.noarch
Preparing packages...
mysql-community-release-el7-5.noarch
[root@chen ~]# rpm -ev --nodeps mysql-community-common-5.6.48-2.el7.x86_64
Preparing packages...
mysql-community-common-5.6.48-2.el7.x86_64
[root@chen ~]# rpm -ev --nodeps mysql-community-client-5.6.48-2.el7.x86_64
Preparing packages...
mysql-community-client-5.6.48-2.el7.x86_64
[root@chen ~]# rpm -ev --nodeps mysql-community-server-5.6.48-2.el7.x86_64
Preparing packages...
mysql-community-server-5.6.48-2.el7.x86_64
warning: /etc/my.cnf saved as /etc/my.cnf.rpmsave
[root@chen ~]# rpm -qa|grep -i mysql
[root@chen ~]# 

2.沒有wget的，先安裝

yum -y install wget

3.下載安裝包

wget http://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm --no-check-certificate

4.安裝mysql源

yum localinstall mysql57-community-release-el7-8.noarch.rpm

5.檢查是否安裝成功了

yum repolist enabled | grep "mysql.*-community.*"

6.安裝mysql並啓動

yum install mysql-community-server
#或者service mysqld start
systemctl start mysqld 
#查看狀態
systemctl status mysqld

7.設置開機啓動

systemctl enable mysqld
systemctl daemon-reload

8.獲取初始化密碼
如果執行獲取命令沒拿到，需要刪除原來安裝的mysql殘留數據

[root@chen ~]# grep 'temporary password' /var/log/mysqld.log 
[root@chen ~]# rm -rf /var/lib/mysql
[root@chen ~]# systemctl restart mysqld
[root@chen ~]# grep 'temporary password' /var/log/mysqld.log
2019-08-07T19:16:44.402628Z 1 [Note] A temporary password is generated for root@localhost: W6+uRkglZ0ex

9.修改密碼

mysql -u root -p
輸入上一步獲取的臨時密碼
#5.7出於安全考慮不讓設置簡單密碼，要先更改其密碼機制
set global validate_password_policy=LOW;
# 設置密碼長度
set global validate_password_length=6;
# 修改密碼
SET PASSWORD = PASSWORD('123456');
ALTER USER 'root'@'localhost' PASSWORD EXPIRE NEVER;
flush privileges;
use mysql;
update user set host = '%' where user = 'root';
# 使配置生效
flush privileges;

10.設置字符集

set character_set_database=utf8;
flush privileges;