CentOS7版本安装Mysql8.0.20版本数据库

CentOS7安装Mysql8.0.20步骤：
官网下载8.0.20Mysql包（bundle版本）
1.
创建mysql文件夹：

[root@localhost ~]# mkdir /usr/local/mysql
[root@localhost ~]# cd /usr/local/mysql/

将下载的mysql包放在创建的MySQL文件夹内：

[root@localhost mysql]# ll
总用量 815000
-rw-r--r--. 1 root root 834560000 5月  13 10:44 mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar

mysql的安装版MD5码查看是否和官网上的相对应：

[root@localhost mysql]# md5sum mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar 
c8d062c1f74d9aab7dbdd5300b202b6e  mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar

将mysql的包解压得到几个内安装包：

[root@localhost mysql]# tar -xvf mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar 
mysql-community-libs-8.0.20-1.el7.x86_64.rpm
mysql-community-embedded-compat-8.0.20-1.el7.x86_64.rpm
mysql-community-test-8.0.20-1.el7.x86_64.rpm
mysql-community-common-8.0.20-1.el7.x86_64.rpm
mysql-community-devel-8.0.20-1.el7.x86_64.rpm
mysql-community-client-8.0.20-1.el7.x86_64.rpm
mysql-community-libs-compat-8.0.20-1.el7.x86_64.rpm
mysql-community-server-8.0.20-1.el7.x86_64.rpm
[root@localhost mysql]# ll
总用量 1630004
-rw-r--r--. 1 root root  834560000 5月  13 10:44 mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar
-rw-r--r--. 1 7155 31415  48822048 3月  27 20:14 mysql-community-client-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415    623508 3月  27 20:14 mysql-community-common-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415   8129988 3月  27 20:14 mysql-community-devel-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415  23599996 3月  27 20:14 mysql-community-embedded-compat-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415   4667884 3月  27 20:14 mysql-community-libs-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415   1277128 3月  27 20:14 mysql-community-libs-compat-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415 512057468 3月  27 20:15 mysql-community-server-8.0.20-1.el7.x86_64.rpm
-rw-r--r--. 1 7155 31415 235369940 3月  27 20:16 mysql-community-test-8.0.20-1.el7.x86_64.rpm

依次安装顺序时common，libs，libs-compat，client，server：

警告：mysql-community-common-8.0.20-1.el7.x86_64.rpm: 头V3 DSA/SHA1 Signature, 密钥 ID ********: NOKEY
准备中...                          ################################# [100%]
正在升级/安装...
   1:mysql-community-common-8.0.20-1.e################################# [100%]
警告：mysql-community-libs-8.0.20-1.el7.x86_64.rpm: 头V3 DSA/SHA1 Signature, 密钥 ID ********: NOKEY
准备中...                          ################################# [100%]
正在升级/安装...
   1:mysql-community-libs-8.0.20-1.el7################################# [100%]
警告：mysql-community-libs-compat-8.0.20-1.el7.x86_64.rpm: 头V3 DSA/SHA1 Signature, 密钥 ID ********: NOKEY
准备中...                          ################################# [100%]
正在升级/安装...
   1:mysql-community-libs-compat-8.0.2################################# [100%]
警告：mysql-community-client-8.0.20-1.el7.x86_64.rpm: 头V3 DSA/SHA1 Signature, 密钥 ID ********: NOKEY
准备中...                          ################################# [100%]
正在升级/安装...
   1:mysql-community-client-8.0.20-1.e################################# [100%]
警告：mysql-community-server-8.0.20-1.el7.x86_64.rpm: 头V3 DSA/SHA1 Signature, 密钥 ID ********: NOKEY
准备中...                          ################################# [100%]
正在升级/安装...
   1:mysql-community-server-8.0.20-1.e################################# [100%]

编辑一下/etc/my.cnf文件：
在最下面增加一行：

lower_case_table_names=1

initialize初始化：

[root@localhost mysql]# mysqld --initialize
[root@localhost mysql]# 

更改一下权限：

[root@localhost mysql]# chown -R mysql:mysql /var/lib/mysql
[root@localhost mysql]# ll  /var/lib/
总用量 8
drwxr-xr-x. 4 root           root             32 5月  13 10:07 AccountsService
drwxr-xr-x. 2 root           root              6 8月   3 2017 alsa
drwxr-xr-x. 2 root           root            274 5月  13 10:14 alternatives
drwx------. 3 root           root             18 5月  13 10:17 authconfig
drwxr-xr-x. 2 root           root              6 8月   3 2017 bluetooth
drwxr-xr-x. 2 chrony         chrony            6 8月   4 2017 chrony
drwxr-xr-x. 3 root           root             17 5月  13 10:06 color
drwxr-xr-x. 4 colord         colord           67 5月  13 10:23 colord
drwxr-xr-x. 2 root           root              6 11月  7 2016 dbus
drwxr-xr-x. 2 root           root              6 8月   4 2017 dhclient
drwxr-xr-x. 2 root           root              6 8月   3 2017 dnsmasq
drwxr-xr-x. 3 root           root             34 5月  13 10:24 flatpak
drwxr-xr-x. 2 root           root              6 6月  24 2014 fprint
drwxr-xr-x. 2 root           root              6 11月  5 2016 games
drwxrwx--T. 5 gdm            gdm              70 5月  13 10:23 gdm
drwxr-xr-x. 2 geoclue        geoclue           6 8月   2 2017 geoclue
drwxr-xr-x. 4 root           root             55 5月  13 02:22 gssproxy
drwxr-xr-x. 2 root           root              6 8月   2 2017 hyperv
drwxr-xr-x. 2 root           root              6 8月   5 2017 initramfs
drwxr-xr-x. 8 root           root             90 5月  13 10:07 iscsi
drwxr-xr-x. 8 root           root             93 5月  13 10:08 libvirt
drwxr-xr-x. 2 root           root              6 11月  6 2016 lldpad
drwxr-xr-x. 2 root           root              6 8月   2 2017 logrotate
drwx------. 2 root           root              6 5月  13 10:06 machines
drwxr-xr-x. 2 root           root             37 5月  13 02:22 misc
drwxr-x---. 2 root           slocate           6 11月  5 2016 mlocate
drwxr-x--x. 6 mysql          mysql          4096 5月  13 11:05 mysql

启动mysql服务看一下服务状态，看Active这一行的状态：

[root@localhost mysql]# systemctl start mysqld.service 
[root@localhost mysql]# systemctl status mysqld.service 
● mysqld.service - MySQL Server
   Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
   Active: active (running) since 三 2020-05-13 11:09:35 CST; 8s ago
     Docs: man:mysqld(8)
           http://dev.mysql.com/doc/refman/en/using-systemd.html
  Process: 16795 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)
 Main PID: 16829 (mysqld)
   Status: "Server is operational"
   CGroup: /system.slice/mysqld.service
           └─16829 /usr/sbin/mysqld

5月 13 11:09:24 localhost.localdomain systemd[1]: Starting MySQL Server...
5月 13 11:09:35 localhost.localdomain systemd[1]: Started MySQL Server.
[root@localhost mysql]#

查看数据库初始的密码：

[root@localhost mysql]# cat /var/log/mysqld.log | grep password
2020-05-13T03:05:16.041238Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: n_t#tk.Z?7)f

使用初始密码登陆数据库：后更改密码：

[root@localhost mysql]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.20

Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>
mysql> ALTER user 'root'@'localhost' identified with mysql_native_password by '123456';
Query OK, 0 rows affected (0.04 sec)

mysql> exit
Bye
[root@localhost mysql]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 8.0.20 MySQL Community Server - GPL

Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> SELECT VERSION;
ERROR 1054 (42S22): Unknown column 'VERSION' in 'field list'
mysql> SELECT VERSION();
+-----------+
| VERSION() |
+-----------+
| 8.0.20    |
+-----------+
1 row in set (0.00 sec)

mysql>

到此可以正常登陆数据库了，可以自行查找开启远程方式。