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Linux下安装mysql8.0.20

安装前准备

1. 下载地址

https://dev.mysql.com/downloads/mysql/

2. 检测是否安装过mysql

# 检测是否安装过mysql
rpm -qa | grep mysql
# 删除命令
rpm -e --nodeps mysql-libs-5.1.73-5.el6_6.x86_64

3. 查询所有Mysql对应的文件夹（删除）

whereis mysql
rm -rf /usr/lib64/mysql /usr/share/mysql
find / -name mysql
rm -rf /etc/selinux/targeted/active/modules/100/mysql

4. 检查mysql用户组和用户是否存在，如果没有，则创建

cat /etc/group | grep mysql
cat /etc/passwd |grep mysql
groupadd mysql
useradd -r -g mysql mysql

安装

1. 下载、上传、解压安装包

官网下载，xftp上传

# 解压
tar -xvf mysql-8.0.20-linux-glibc2.12-x86_64.tar.xz

2. 将解压的文件移动到/usr/local下，并重命名为mysql

# 移动位置并重命名
mv /mysql-8.0.20-linux-glibc2.12-x86_64 /usr/local/mysql

3. 进入/usr/local/mysql目录下，创建data文件夹，并授权

cd /usr/local/mysql/
# 创建文件夹
mkdir data
# 给文件夹授权
chown -R root:root /usr/local/mysql
# 给文件夹授权
chown -R mysql:mysql /usr/local/mysql/data/

4. 初始化数据库，并会自动生成随机密码，记下等下登陆要用

# 初始化数据库，mysql的bin目录下的mysqld命令
/usr/local/mysql/bin/mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data

临时密码：root@localhost:后面的那串代码

补充说明：
此步可能会出错：

出现该问题首先检查该链接库文件有没有安装使用，命令进行核查。
并安装文件，安装完成之后重新初始化。

# 检测命令
rpm -qa|grep libaio
# 
yum install  libaio-devel.x86_64
# 
yum -y install numactl

5. cp /usr/local/mysql/support-files/my-default.cnf /etc/my.cnf

复制过去，其实也就是空白页，一开始没有my-default.cnf这个文件，可以用touch my-default.cnf命令创建一个，并配置权限

chmod 777 ./my-default.cnf 

6. 配置my.cnf

vi /etc/my.cnf

[mysqld]
 
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
 
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
 
# These are commonly set, remove the # and set as required.
basedir = /usr/local/mysql
datadir = /usr/local/mysql/data
socket = /tmp/mysql.sock
log-error = /usr/local/mysql/data/error.log
pid-file = /usr/local/mysql/data/mysql.pid
port = 3306
#lower_case_table_names = 1
# server_id = .....
# socket = .....
#lower_case_table_names = 1
max_allowed_packet=32M
default-authentication-plugin = mysql_native_password
#lower_case_file_system = on
#lower_case_table_names = 1
log_bin_trust_function_creators = ON
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M 
 
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

如果后期mysql运行报错，可以直接到log-error = /usr/local/mysql/data/error.log目录下直接查看错误日志
命令:cat /usr/local/mysql/data/error.log

7. 开机自启，进入/usr/local/mysql/support-files进行设置

cd support-files/
cp mysql.server /etc/init.d/mysql 
chmod +x /etc/init.d/mysql

8. 注册服务并检测

• 注册

chkconfig --add mysql

如果命令没有，在需要处理chkconfig

rpm -aq |grep chkconfig
export PATH=/sbin:$PATH
chkconfig
echo $PATH
PATH="$PATH":/sbin
echo $PATH

• 检测

chkconfig --list mysql

9. etc/ld.so.conf要配置路径，不然报错

vim /etc/ld.so.conf
 
# 添加如下内容:
/usr/local/mysql/lib

10. 配置环境变量

# 配置环境变量
vim /etc/profile

# 添加如下内容：
# MYSQL ENVIRONMENT
export PATH=$PATH:/usr/local/mysql/bin:/usr/local/mysql/lib

# 系统重新加载文件，记得一定要
source /etc/profile

11. 登陆，修改密码

密码：第4步初始化数据库随机生成得密码，输入密码不显示。

[root@VM_0_3_centos support-files]# service mysql start
Starting MySQL.. SUCCESS! 
[root@VM_0_3_centos support-files]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 82
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> alter user 'root'@'localhost' identified by 'kid+1412';
Query OK, 0 rows affected (0.01 sec)

mysql> 

12. 开启Navicat远程连接

# 登录
[root@VM_0_3_centos support-files]# mysql -uroot -p 
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2582
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.
# 选择mysql数据库
mysql> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
# 查看用户信息
mysql> select host, user, authentication_string, plugin from user;
+-----------+------------------+------------------------------------------------------------------------+-----------------------+
| host      | user             | authentication_string                                                  | plugin                |
+-----------+------------------+------------------------------------------------------------------------+-----------------------+
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| localhost | root             | $A$005$=!..iRO=k:x_>qiFtXTYJmwgur/2pJH1mfk26FBL.1YZOC.YcBw8auuFFM0 | caching_sha2_password |
+-----------+------------------+------------------------------------------------------------------------+-----------------------+
4 rows in set (0.00 sec)
# 更新root信息
mysql> update user set host = '%' where user = 'root';
Query OK, 1 row affected (0.02 sec)
Rows matched: 1  Changed: 1  Warnings: 0
# 授权root用户可以远程登陆，失败
mysql> GRANT ALL ON *.* TO 'root'@'%';
ERROR 1410 (42000): You are not allowed to create a user with GRANT
# 立即生效，重新授权
mysql> flush privileges; 
Query OK, 0 rows affected (0.02 sec)
# 授权root用户可以远程登陆
mysql> GRANT ALL ON *.* TO 'root'@'%';
Query OK, 0 rows affected (0.02 sec)
# 立即生效
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)
# 
mysql> alter user 'root'@'%' identified with mysql_native_password by 'kid+1412';
Query OK, 0 rows affected (0.01 sec)
# 立即生效
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
# 退出
mysql> exit
Bye

13.navicat连接成功

Mysql8.0.20 创建用户并授权

https://blog.csdn.net/qq_37040886/article/details/107300838