Python AssertionError:ForeignKey的第一个参数必须是模型、模型名称或字符串';自我';
我刚刚创建了这样一个模型:Python AssertionError:ForeignKey的第一个参数必须是模型、模型名称或字符串';自我';,python,django,Python,Django,我刚刚创建了这样一个模型: from django.db import models # Create your models here. class Category: title = models.CharField(max_length=50) slug = models.CharField(max_length=200) cat_image = models.ImageField(upload_to='images/') def __str__(s
from django.db import models
# Create your models here.
class Category:
title = models.CharField(max_length=50)
slug = models.CharField(max_length=200)
cat_image = models.ImageField(upload_to='images/')
def __str__(self):
return self.title
class Brand:
title = models.CharField(max_length=50)
slug = models.CharField(max_length=200)
brand_image = models.ImageField(upload_to='images/')
def __str__(self):
return self.title
class UOM:
title = models.CharField(max_length=100)
def __str__(self):
return self.title
class Product_Images:
multi_images = models.ImageField(upload_to='images/')
class Product:
name = models.CharField(max_length=100)
slug = models.CharField(max_length=200)
category = models.ForeignKey(Category, on_delete=models.CASCADE)
brand = models.ForeignKey(Brand, on_delete=models.CASCADE)
price = models.IntegerField(null=True, blank=True)
height = models.IntegerField(null=True, blank=True)
weight = models.IntegerField(null=True, blank=True)
length = models.IntegerField(null=True, blank=True)
color = models.IntegerField(null=True, blank=True)
stock = models.BooleanField()
SKU = models.CharField(max_length=150)
def __str__(self):
return self.name
class Customer:
phone_number = models.CharField(max_length=11)
first_name = models.CharField(max_length=10)
last_name = models.CharField(max_length=10)
email = models.CharField(max_length=20)
password = models.CharField(max_length=10)
def __str__(self):
return self.first_name
class Order:
customer = models.ForeignKey(Customer, on_delete=models.CASCADE)
invoice = models.CharField(max_length=16, null=True, blank=True)
phone = models.CharField(max_length=12)
address = models.CharField(max_length=150)
但是面对这个错误,我不知道我为什么会犯这样的错误。如果删除一些字段,我甚至无法进行迁移。它说没有检测到任何更改,但我更改了一些字段,仍然收到这种错误。有人能帮我解决这个问题吗。请解释为什么我会犯这种错误,我在这里找不到任何问题。我在macos上也面临着这个没有变化的问题。我正在更改一些字段,但它仍然表示未检测到任何更改。django中的模型必须如下所示:
class ModelClass(models.Model):
难道不是所有的模型都应该从django.db.models继承吗?