Question

我有一个带有可选字段的复杂模型，我尝试使用表单保存它，每次都会收到错误消息：“ FOREIGN KEY约束失败”

我在表中的所有字段都是可选的，并且表单为空，因此应允许您保存空模型。

models.py

class Ordering(models.Model):
    massage_product = models.OneToOneField(Product, on_delete=models.CASCADE, null=True, blank=True, default = 1)
    masseurs = models.OneToOneField(Masseurs, on_delete=models.CASCADE, null=True,  blank=True, default = 1)
    massage_time_interval = models.CharField(max_length=5, blank=True)
    price = models.CharField(max_length=5, blank=True)
    day_week = models.CharField(max_length=15, choices=DAY_OF_WEEK, default=date.today, blank=True)
    time = models.OneToOneField(Time, on_delete=models.CASCADE, null=True, blank=True, default = 1)
    place = models.OneToOneField(PlaceMassage, on_delete=models.CASCADE, null=True, blank=True, default = 1)
    payment_method = models.CharField(max_length=1, choices=PAYMENT_METHODS, default='G', blank=True)
    name = models.CharField(max_length=50, blank=True)
    surname = models.CharField(max_length=50, blank=True)
    e_mail = models.EmailField(blank=True)
    additional_requests = models.TextField(blank=True)
    phone_number = models.CharField(max_length=15, blank=True)
    reminder_visit = models.BooleanField(default=True, blank=True)
    website_rules = models.BooleanField(default=True, blank=True)
    city = models.CharField(max_length=50, blank=True)
    street = models.CharField(max_length=50, blank=True)
    street_number = models.CharField(max_length=10, blank=True)
    hom_number = models.CharField(max_length=10, blank=True)
    zip_code = models.CharField(max_length=10, blank=True)
    created_at_data = models.DateTimeField(auto_now_add=True)
    updated_at_data = models.DateTimeField(auto_now=True)

forms.py

if request.method == 'POST' and 'btn_massage_order' in request.POST:
    ordering_form = OrderingMassageForm(data=request.POST)
    if ordering_form.is_valid():
        ordering = OrderingMassage()
        ordering.save()
else:
     ordering_form = OrderingMassageForm()

错误环境：

Request Method: POST
Request URL: http://127.0.0.1:8000/massage_order/2_1_90_100/

Django Version: 2.0
Python Version: 3.7.0
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'app',
 'multiselectfield',
 'crispy_forms']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback:

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

The above exception (FOREIGN KEY constraint failed) was the direct cause of the following exception:

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\exception.py" in inner
  35.             response = get_response(request)

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "C:\Users\tymot\Desktop\PROJEKT\app_test_form-czysty\app_rama\app\views.py" in massage_order
  399.             ordering.save()

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\base.py" in save
  729.                        force_update=force_update, update_fields=update_fields)

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\base.py" in save_base
  759.             updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\transaction.py" in __exit__
  212.                         connection.commit()

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\base\base.py" in commit
  261.         self._commit()

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\utils.py" in __exit__
  89.                 raise dj_exc_value.with_traceback(traceback) from exc_value

File "C:\Users\tymot\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

Exception Type: IntegrityError at /massage_order/2_1_90_100/
Exception Value: FOREIGN KEY constraint failed

Django admin允许您保存一个空表格，为什么我不允许呢？任何帮助将不胜感激。

Answer 1

尝试

if request.method == 'POST' and 'btn_massage_order' in request.POST:
    ordering_form = OrderingMassageForm(request.POST)
    if ordering_form.is_valid():
        ordering = ordering_form(commit=False)
        ordering.save()
else:
     ordering_form = ordering_form()

希望有帮助

Answer 2

您的模型中具有以下一对一关系：

massage_product = models.OneToOneField(Product, ... default = 1)
masseurs = models.OneToOneField(Masseurs, ... default = 1)

这意味着每个Ordering 和每个Order（{{1只能有一个Product（您是说Masseurs？ }}？）。这可能不是您想要的。除此之外，您还可以设置默认值Masseur，该值可以运行一次，但不会运行两次，因为ID为1的{{1}} / Product仅可以与一个记录在Masseurs中。

我怀疑这是您失败的FK约束的来源。

这是Django docs对1的评价：

从概念上讲，这类似于具有unique = True的ForeignKey

外键约束失败Django

2 个答案: