CentOs7.9安装mysql8

1，先升级centos
yum update
2，检查centos7中是否有MariaDB，MariaDB与MySQL关系请自行查阅
rpm -qa | grep mariadb
如果存在删除
rpm -e –nodeps 软件名
3，检查是否安装了Mysql
rpm -qa | grep -i mysql
如果存在就卸载
rpm -e –nodeps 软件名
查找mysql文件，并将其删除
find / -name mysql
whereis mysql
将find命令和whereis命令查询到的mysql文件全部删除
rm -rf 查询到的mysql路径
删除mysql配置文件
rm /etc/my.cnf
确认是否全部删除mysql
rpm -qa | grep -i mysql

4正式下载安装
下载镜像
wget https://mirrors.163.com/mysql/Downloads/MySQL-8.0/mysql-8.0.36-1.el7.x86_64.rpm-bundle.tar
镜像不对直接官网下载：

查询系统架构
uname -m

5，上传安装包并解压
tar -xvf mysql-8.0.36-1.el7.x86_64.rpm-bundle.tar

6,解压后安装
按照顺序按照，缺少组件安装组件
rpm -ivh mysql-community-common-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-plugins-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-icu-data-files-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-compat-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-debuginfo-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-debug-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-embedded-compat-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-devel-8.0.36-1.el7.x86_64.rpm
rpm -ivh mysql-community-test-8.0.36-1.el7.x86_64.rpm

缺少组件
yum install libaio
yum install openssl-devel -y
yum install -y perl
yum -y install autoconf
yum install perl-JSON

7.初始化数据库
mysqld –initialize –console

8.目录授权，否则启动失败
chown -R mysql:mysql /var/lib/mysql/

9.启动msyql服务

systemctl start mysqld

10.在/var/log/mysqld.log下查看临时密码

cat /var/log/mysqld.log | grep password
用临时密码登录到数据库

mysql -u root -p + 回车键

11，执行下列mysql命令 修改密码

alter USER ‘root’@’localhost’ IDENTIFIED BY ‘新密码(必须包含：数字大小写字母特殊字符)’;
alter USER ‘root’@’localhost’ IDENTIFIED BY ‘1QAZ2wsx’;

12， 依次执行下列mysql命令 授权远程连接

查看所有用户是否可以远程连接，依次执行下列命令：

show databases;
use mysql;
select host, user, authentication_string, plugin from user;

修改root用户host值，使root用户可以远程登录
update user set host = “%” where user=’root’;

刷新权限
flush privileges;

13，使用mysql客户端登录数据库报错如下图
mysql -u root -p+ 回车键+输入root用户的密码 登录 ;
show databases;
use mysql;
alter USER ‘root’@’%’ IDENTIFIED WITH mysql_native_password BY ‘root用户的密码’;
flush privileges;