class Blog(models.Model):
    title = models.CharField(max_length=)
    #这里要注意外键关联 如果 关联的类没有在之前没用定义 那么一定要加引号   这里采用一个博客对应一个博客类型 一一对应
blog_type = models.ForeignKey('BlogType',on_delete=models.DO_NOTHING)
    content = models.TextField()
    author = models.ForeignKey(User,on_delete=models.DO_NOTHING)
    created_time = models.DateTimeField(auto_now_add=True)
    last_updated_time = models.DateTimeField(auto_now=True)
    def __str__(self):
        return "<Blog: %s>" %self.title

class BlogType(models.Model):
    type_name=models.CharField(max_length=)

    def __str__(self):
        return self.type_name

import pymysql         # 一定要添加这两行！通过pip install pymysql！

pymysql.install_as_MySQLdb()

DATABASES = {

    'default': {

        'ENGINE': 'django.db.backends.mysql',

        'NAME': 'mysite',

        'HOST': '123.2X7.XX9.194',

        'USER': 'root',

        'PASSWORD': 'XXX',

        'PORT': '',

    }

}

#修改

LANGUAGE_CODE = 'zh-Hans'

TIME_ZONE = 'Asia/Shanghai'

USE_I18N = True

USE_L10N = True

USE_TZ = True

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'blog',
]

from .models import BlogType,Blog

@admin.register(BlogType)

class BlogTypeAdmin(admin.ModelAdmin):

    list_display = ("id", "type_name")

@admin.register(Blog)

class BlogAdmin(admin.ModelAdmin):

    list_display = ("title","blog_type","author","create_time","last_updated_time" )

# Register your models here.

##也可以

#admin.site.register(BlogType) 这样注册的确定是 全部都会显示在后台 

    query = query.decode(errors='replace')

AttributeError: 'str' object has no attribute 'decode'