Linux下mysql創建用戶並設置權限，設置遠程連接

為了安全考慮，OneinStack僅允許雲主機本機（localhost）連接數據庫，如果需要遠程連接數據庫，需要如下操作：
打開iptables 3306端口

# iptables -I INPUT 4 -p tcp -m state --state NEW -m tcp --dport 3306 -j ACCEPT
# service iptables save //保存iptables規則

# iptables -nvL //查看端口開啟情況

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root用戶登錄mysql   mysql5.7版本使用
mysql>create database SubAccount;
mysql>GRANT ALL PRIVILEGES ON SubAccount.* TO drcloudapi@"%" IDENTIFIED BY "123456" WITH GRANT OPTION;  // *.*表示所有庫的所有表
mysql>flush privileges;
mysql>use SubAccount;

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mysql5.7版本password已經改為authentication_string

insert into mysql.user(Host,User,authentication_string) values("%","zizhanghu",password("123456")); //<=5.1版本能用
//GRANT ALL PRIVILEGES ON SubAccount.* TO zizhanghu@"%" IDENTIFIED BY "123456" WITH GRANT OPTION;
//為用戶創建一個數據庫(SubAccount)：
mysql>create database SubAccount;
//授權yanzm用戶擁有SubAccount數據庫的所有權限（某個數據庫的所有權限）：
mysql>grant all privileges on SubAccount.* to zizhanghu@'%' identified by '123456';
//刷新系統權限表
mysql>flush privileges;
mysql>use SubAccount;