centos7下rpm安裝mysql5.7

1.wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.22-1.el7.x86_64.rpm-bundle.tar
2.按照依賴關係依次安裝rpm包 依賴關係依次爲common→libs→client→server

rpm -ivh mysql-community-common-5.7.22-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-5.7.22-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-5.7.22-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-5.7.22-1.el7.x86_64.rpm

安裝報錯：警告：mysql-community-common-5.7.22-1.el7.x86_64.rpm: 頭V3 DSA/SHA1 Signature, 密鑰 ID 5072e1f5: NOKEY
解決方法：rpm -ivh mysql-community-common-5.7.22-1.el7.x86_64.rpm --force --nodeps

3.啓動

systemctl start mysqld.service    啓動mysql
systemctl status mysqld.service  查看mysql狀態
systemctl stop mysqld.service   關閉mysql

4.修改密碼

查看密碼：grep 'temporary password' /var/log/mysqld.log

更改策略，設置 validate_password_policy=0;
mysql> set global validate_password_policy=0;    # 此時，新密碼長度大於等於8位纔有效，不然報錯
修改有效密碼長度：

mysql> set global validate_password_length=1;
Query OK, 0 rows affected (0.00 sec)
無論設置  validate_password_length=1,仍是2,3,4 ,‘使密碼長度生效’這個參數的實際值都是4。超過4後設置是多少實際就是多少。

step2：重設密碼：
mysql> set password for root@localhost=password('9527');