1、centos7 中安装 mysql 8.x
（1）下载安装包
wget https://downloads.mysql.com/archives/get/p/23/file/mysql-8.0.33-1.el7.x86_64.rpm-bundle.tar
（2）解压
tar -xf mysql-8.0.33-1.el7.x86_64.rpm-bundle.tar
（3）卸载maridb
yum -y remov mariadb-libs.x86_64
（4）下载net-tools
yum -y install net-tools
（5）下载rpm -ivh mysql-community-server-8.0.33-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.33-1.el7.x86_64.rpm
按要求一个一个依赖包下载，最后达到server软件包成功下载即可
（6）修改配置文件
vim /etc/my.cnf //添加explicit_defaults_for_timestamp=true
rm -rf /var/lib/mysql/*
（7）初始化配置mysql
mysqld --initialize
（8）启动mysql服务
systemctl start mysqld.service
（9）设置mysql开机自启
systemctl enable mysqld
（10）获得初始化密码
cat /var/log/mysqld.log | grep password
2024-08-02T02:04:03.141224Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: !iI-ht4hXM5,
（11）使用初始密码登陆
mysql -uroot -p
!iI-ht4hXM5,
（12）设置密码
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'Root@123456';
在mysql内将密码修改为Root@123456
（13）修改远程权限
create user 'root'@'%' identified with mysql_native_password by 'Root@123456';
grant all privileges on *.* to 'root'@'%' with grant option;
flush privileges;
2、mysql基础操作
（1）创建库
mysql> create datababse test charset utf8;
Query OK, 1 row affected, 1 warning (0.01 sec)
（2）查看库
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
5 rows in set (0.00 sec)
（3）删除库
mysql> drop database hh;
Query OK, 0 rows affected (0.04 sec)
（4）选择使用数据库
mysql> use test;
Database changed
（5）创建表
mysql> create table student(
-> id int not null auto_increment,
-> name varchar(20) not null,
-> passwd varchar(20) not null,
-> primary key (id)
-> )comment = 'us';
Query OK, 0 rows affected (0.05 sec)
（6）查看表
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| student |
| user |
+----------------+
2 rows in set (0.01 sec)
（7）删除表
mysql> drop table student;
Query OK, 0 rows affected (0.03 sec)
（8）查看表结构
mysql> describe user;
+----------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+----------------+
| id | int | NO | PRI | NULL | auto_increment |
| username | varchar(45) | NO | UNI | NULL | |
| password | varchar(45) | NO | | NULL | |
+----------+-------------+------+-----+---------+----------------+
3 rows in set (0.01 sec)
（9）查看创建表代码
mysql> show create table user;
+-------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+-------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| user | CREATE TABLE `user` (
`id` int NOT NULL AUTO_INCREMENT,
`username` varchar(45) NOT NULL,
`password` varchar(45) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `username_UNIQUE` (`username`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8mb3 COMMENT='us' |
+-------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
（10）新增列
mysql> alter table user add column realname varchar(20) null after password;
Query OK, 0 rows affected (0.01 sec)
Records: 0 Duplicates: 0 Warnings: 0
（11）修改列名
mysql> alter table user change column realname zsxm varchar(20) null default null;
Query OK, 0 rows affected (0.01 sec)
Records: 0 Duplicates: 0 Warnings: 0
（12）删除列
mysql> alter table user drop column zsxm;
Query OK, 0 rows affected (0.04 sec)
Records: 0 Duplicates: 0 Warnings: 0
（13）添加记录
mysql> insert into user(id,username,password) values(5,'小六','xiaoliu'),(6,'小七','xiaoqi');
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
（14）查看记录
mysql> select * from user;
+----+----------+----------+
| id | username | password |
+----+----------+----------+
| 1 | 张三 | 123 |
| 2 | 赵六 | zhaoliu |
| 3 | 王五 | wangwu |
| 4 | 李四 | lisi |
| 5 | 小六 | xiaoliu |
| 6 | 小七 | xiaoqi |
+----+----------+----------+
6 rows in set (0.00 sec)
（15）删除记录
mysql> delete from user where username='张三';
（16）修改记录
mysql> update user set password=123 where username='小六';
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
3、mysql图示化操作软件使用
打开软件
点击加号-------------输入连接名字（随便）------------hostname（数据库主机的ip地址）----------------------ok
点击mysql02
输入密码
进入软件
如果出现以下页面：1、检查防火墙 2、查看是否为远程授权
