python - (Django) OperationalError at/no such column : minishop_app_products. user_id

Question

我正在建立一个电子商务商店，我正在从数据库中提取项目并在模板上呈现。但我有这个问题。我正在尝试呈现一个动态 url 并返回一些错误。我试过调试它但无济于事。

这是它显示的错误(在浏览器上):

OperationalError at /

no such column: minishop_app_products.user_id

下面是一些代码片段:

View.py

from django.shortcuts import render
from .models import *
from django.http import HttpResponse


def index(request):

    header = headerSlider.objects.all()
    new_item = Products.objects.all()

    context = {
        'header': header,
        'new_item': new_item,
        }
    return render(request, 'index.html', context)

def product_single(request, pk):
    single_product = Products.objects.get(pk=id)

    print(single_product)
    sizes = Size.objects.all()

    context = {
        'single_product':single_product,
        'sizes': sizes
        }

    return render(request, 'product-single.html', context)

模型.py

from django.db import models
from django.contrib.auth.models import User


class headerSlider(models.Model):
    title = models.CharField(max_length=200 , null=True)
    description = models.CharField(max_length=400 , null=True)
    category = models.CharField(max_length=200 , null=True)
    image = models.ImageField(null=True, blank=False)


    def __str__(self):
        return self.title

    class  Meta:
        verbose_name_plural = 'Head Slider'

class Size(models.Model):
    size = models.CharField(max_length=50)

    def __str__(self):
        return self.size

class Products (models.Model):
    product_title = models.CharField(max_length=200 , null=True)
    product_price = models.FloatField()
    product_category = models.CharField(max_length=200 , null=True)
    product_image = models.ImageField(null=True, blank=False)


    detail_title1 = models.CharField(max_length=200 , null=True)
    detail_title2 = models.CharField(max_length=200 , null=True)
    detail_description1 = models.TextField(max_length=500 , null=True)
    detail_description2 = models.TextField(max_length=500 , null=True)
    quantity_avail = models.IntegerField()
    quantity_sold = models.IntegerField()
    manufacturer_detail = models.TextField(max_length=500 , null=True)
    detail_image1 = models.ImageField(null=True, blank=False)
    detail_image2 = models.ImageField(null=True, blank=False)
    detail_image3 = models.ImageField(null=True, blank=False)
    detail_image4 = models.ImageField(null=True, blank=False)
    user = models.ForeignKey(to=User, on_delete=models.CASCADE, null=True, blank=True)
    size = models.ForeignKey(Size, on_delete=models.CASCADE, default="Medium")


    def __str__(self):
        return self.product_title

    class  Meta:
        verbose_name_plural = 'Products'

另外:我在 models.py 文件中添加了一些字段(并尝试迁移)。迁移时，它会返回此错误:

TypeError: Field 'id' expected a number but got <User: >.

网址.py

from django.urls import path
from . import views

urlpatterns = [
    path('', views.index, name='index'),
    path('blog/', views.blog, name='blog'),
    path('blog-single/', views.blog_single, name='blog-single'),
    path('about/', views.about, name='about'),
    path('contact/', views.contact, name='contact'),
    path('cart/', views.cart, name='cart'),
    path('checkout/', views.checkout, name='checkout'),
    path('product/<str:id>', views.product_single, name='product_single'),
    path('shop/', views.shop, name='shop'),
]

迁移错误 - 来自终端

Applying minishop_app.0006_auto_20200920_0938...Traceback (most recent call last):
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 1774, in get_prep_value
    return int(value)
TypeError: int() argument must be a string, a bytes-like object or a number, not 'User'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 22, in <module>
main()
  File "manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/base.py", line 85, in wrapped
    res = handle_func(*args, **kwargs)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/core/management/commands/migrate.py", line 243, in handle
    post_migrate_state = executor.migrate(
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/migrations/migration.py", line 124, in apply
operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/migrations/operations/fields.py", line 104, in database_forwards
    schema_editor.add_field(
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/backends/sqlite3/schema.py", line 328, in add_field
    self._remake_table(model, create_field=field)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/backends/sqlite3/schema.py", line 189, in _remake_table
    self.effective_default(create_field)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/backends/base/schema.py", line 303, in effective_default
    return field.get_db_prep_save(self._effective_default(field), self.connection)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/models/fields/related.py", line 971, in get_db_prep_save
    return self.target_field.get_db_prep_save(value, connection=connection)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 823, in get_db_prep_save
    return self.get_db_prep_value(value, connection=connection, prepared=False)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 2388, in get_db_prep_value
    value = self.get_prep_value(value)
  File "/home/uniquezra/Desktop/Artivate_Reg/regenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 1776, in get_prep_value
    raise e.__class__(
TypeError: Field 'id' expected a number but got <User: >.

0006_auto_20200920_0938

from django.conf import settings
import django.contrib.auth.models
from django.db import migrations, models
import django.db.models.deletion


class Migration(migrations.Migration):

dependencies = [
    migrations.swappable_dependency(settings.AUTH_USER_MODEL),
    ('minishop_app', '0005_auto_20200919_1736'),
]

operations = [
    migrations.AlterModelOptions(
        name='headerslider',
        options={'verbose_name_plural': 'Head Slider'},
    ),
    migrations.AlterModelOptions(
        name='products',
        options={'verbose_name_plural': 'Products'},
    ),
    migrations.AddField(
        model_name='products',
        name='owner',
        field=models.ForeignKey(default=django.contrib.auth.models.User, on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
    ),
]

Answer 1

显然你弄乱了你的迁移文件。我很确定问题出在这个声明中:

migrations.AddField(
  model_name='products',
  name='owner',
  field=models.ForeignKey(default=django.contrib.auth.models.User, on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
),

我认为不应该有 default参数传递给 models.ForeignKey根本(我相信这是导致错误 TypeError: Field 'id' expected a number but got <User: >. 的原因)，加上 name应该是 'user'如您的模型文件中所指定，而不是 'owner' .

所以我认为这应该是这样工作的:

migrations.AddField(
  model_name='products',
  name='user',
  field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
),

如果按照我的建议更改它不会修复它:

1. 删除所有迁移文件
2. 删除您的数据库
3. 运行 ./manage.py makemigrations
4. 运行 ./manage.py migrate
5. 再次启动服务器