OperationalError: (1044, "Access denied for user ''@'localhost' to database 'mydb'")

该错误为django 连接数据库没有权限，解决办法是：

DROP DATABASE IF EXISTS `mydb`;
CREATE DATABASE `mydb`
    DEFAULT CHARACTER SET utf8
    DEFAULT COLLATE utf8_general_ci;

USE 'mysql';
GRANT ALL PRIVILEGES ON mydb.* TO 'mydb_user'@'localhost' IDENTIFIED BY 'your_password'

WITH GRANT OPTION;
FLUSH PRIVILEGES;

　然后修改你的django 项目设置：

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'mydb',                  
        'USER': 'mydb_user',             
        'PASSWORD': 'your_password',                  
        'HOST': '',                     
        'PORT': '',                      
    }
}