安裝客戶端和依賴環境
sudo apt install mysql-server #安裝mysql服務器端
sudo apt install mysql-client #安裝mysql客戶端
sudo apt install libmysqlclient-dev #安裝服務端/客戶端依賴環境（可有可無，建議安裝）
初始化MySQL（MySQL 5.7並未設置默認密碼，需要初始化，即運行安全向導）
sudo mysql_secure_installation
安全向導：
1.（是否設置隨機密碼，Y/y隨機密碼， N/n自己輸入密碼）
VALIDATE PASSWORD PLUGIN can be used to test passwords...
Press y|Y for Yes, any other key for No: N (我的選項)
Please set the password for root here...
New password: (輸入密碼)
Re-enter new password: (重復輸入)
2.（是否刪除匿名用戶，建議刪除）
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them...
Remove anonymous users? (Press y|Y for Yes, any other key for No) : Y (我的選項)
3.（是否禁止root賬戶遠程登陸，建議禁止）
Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network...
Disallow root login remotely? (Press y|Y for Yes, any other key for No) : Y (我的選項)
4.（是否刪除test數據庫，建議刪除）
By default, MySQL comes with a database named 'test' that
anyone can access...
Remove test database and access to it? (Press y|Y for Yes, any other key for No) : Y (我的選項)
5.（是否重新加載權限表，應該重新加載）
Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.
Reload privilege tables now? (Press y|Y for Yes, any other key for No) : Y (我的選項)
修改配置文件(具體的看是否需要遠程訪問數據庫)
sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf
/bind #查找bind-address,然后注釋該行並保存
重啟MySQL服務
sudo service mysql restart
從MySQL-Client登陸MySQL(首次登陸建議以root用戶身份登陸)
mysql -u root -p
創建用來遠程登陸的用戶
create user 用戶名（非root用戶）
為新建立的用戶賦予相應權限
grant all privileges on *.* to 'username'@'%' identified by 'password' with grant option;
# grant 修改用戶權限的關鍵字
# all(增、刪、改、查、創建數據庫和表等，除grant外的所有權限)
# on 后面跟數據庫名.表名（*代表所有）
# to 'username'@'ip'(%代表所有IP均可訪問該數據庫)
# identified by 'password'
# 關鍵字：privileges、with grant option
必須使用flush privileges的兩種情況
1、改密碼。
2、授權超用戶。
flush privileges 命令本質上的作用是將當前user和privilige表中的用戶信息/權限設置從mysql庫(MySQL數據庫的內置庫)中提取到內存里