rpm -qa|grep -i mysql
安装了会显示: bt-mysql57-5.7.31-1.el7.x86_64
rpm -e bt-mysql57-5.7.31-1.el7.x86_64
find / -name mysql
/var/lib/mysql
/var/lib/mysql/mysql
/usr/lib64/mysql
.....
rm -rf /var/lib/mysql
rm -rf /var/lib/mysql
rm -rf /usr/lib64/mysql
....
注意:卸载mysql后/etc/my.cnf不会删除,需要进行手动删
rm -rf /etc/my.cnf
再次执行 rpm -qa|grep -i mysql 检查一下
也可以下载下来再上传到linux
wget -c https://repo.huaweicloud.com/mysql/Downloads/MySQL-5.7/mysql-5.7.37-1.el7.x86_64.rpm-bundle.tar
ls命令查看

tar xf mysql-5.7.37-1.el7.x86_64.rpm-bundle.tar
ls命令查看

yum remove mariadb-libs
rpm -ivh mysql-community-client-5.7.37-1.el7.x86_64.rpm mysql-community-common-5.7.37-1.el7.x86_64.rpm mysql-community-libs-5.7.37-1.el7.x86_64.rpm mysql-community-server-5.7.37-1.el7.x86_64.rpm
可能出现的问题:
1、错误:依赖检测失败:
libncurses.so.5()(64bit) 被 mysql-community-client-5.7.37-1.el7.x86_64 需要
libtinfo.so.5()(64bit) 被 mysql-community-client-5.7.37-1.el7.x86_64 需要
执行命令:yum install libncurses*
2、错误:依赖检测失败:
net-tools 被 mysql-community-server-5.7.37-1.el7.x86_64 需要
执行命令: yum install net-tools
systemctl start mysqld
systemctl status mysqld

P=`awk '/temporary password/ {print $NF}' /var/log/mysqld.log`
mysql -uroot -p$P

登录成功~
ALTER USER root@localhost identified by 'MySQL@123';
密码为大写字母、小写字母、特殊字符、数字的8位及以上的组合
# 开放33.6端口
firewall-cmd --zone=public --add-port=3306/tcp --permanent
# 重载防火墙配置
firewall-cmd --reload
然后使用Navicat等工具测试连接