Why can not I submit a double form to the database - django

Question

I created a form view and when I want to save a form with two modules I see "IntegrityError". Please help, Thank you in advance
class Place(models.Model):
LocalName = models.CharField('Nazwa Lokalu', max_length=200)
slug = models.SlugField('Link', max_length=100, default="")
LocalImg = models.ImageField('Zdjęcie Lokalu',
upload_to='Place/static/locals/img', blank=True, max_length=20000)
LocalAdress = models.CharField('Adres', max_length=500)
LocalNumberPhone = models.CharField('Numer telefonu', max_length=9)
LocalHours = models.TextField(verbose_name='Godziny otwarcia',
max_length=20000)
def get_aboslute_url(self):
return reverse("place:place_create", kwargs={'id': self.id})
class Meta:
verbose_name = "Lokal"
verbose_name_plural = "Lokale"
def __str__(self):
return self.LocalName
class Menu(models.Model):
place = models.ForeignKey(Place, on_delete=models.CASCADE,
related_name="place", default="")
Dinner = models.CharField("Nazwa potrawy",blank=True, default="",
max_length=200)
DinnerComponents = models.CharField("Składniki",blank=True, default="",
max_length=20009)
PizzaPrice = models.CharField("Rozmiar i cena Pizzy",
help_text="np.Mała-10zł", default="", blank=True, max_length=300)
Price = models.DecimalField("Cena",default="00", max_digits=5,
decimal_places=2)
class Meta:
verbose_name = "Menu"
verbose_name_plural = "Menu"
views.py
def create_place(request):
form = PlaceForm()
sub_form = MenuForm()
if request.POST:
form = PlaceForm(request.POST)
sub_form = MenuForm(request.POST)
if form.is_valid() and sub_form.is_valid():
place = form.save(commit=False)
place.location = sub_form.save()
place.save()
context = {
'form': form,
'sub_form': sub_form
}
return render(request, 'posts/layout.html', context)
Forms.py
class PlaceForm(forms.ModelForm):
class Meta:
model = Place
fields = ('LocalName', 'LocalAdress', 'LocalNumberPhone','LocalHours',)
class MenuForm(forms.ModelForm):
class Meta:
model = Menu
fields = ('Dinner','DinnerComponents','DinerCategory', 'Price',)
After filling in the form and clicking submit, an error will appear "NOT NULL constraint failed: posts_menu.place_id"

Answer 1

You have to first save a Place then assign the saved place to the Menu and finally save the menu.
if form.is_valid() and sub_form.is_valid():
place = form.save()
menu = sub_form.save(commit=False)
menu.place = place
menu.save()
That's because a Menu needs a place foreign key otherwise it cannot be saved.
(Note: why do you mix snake_case and CamelCase for your field names? It's terribly difficult to know how your model's properties are called. Python's convention is snake_case for all properties/methods/variables)