Error using Django model forms with multiple databases

Question

I want create a simple form in my app with foreign key. I've two databases, a is default of Django, and the other is a legacy database.

The message of error that show is this: Table 'django.customer' doesn't exist . But I want select my other database, not Django. How I do this?

This is my model:

from django.db import models
from register.models import Customer

class Service(models.Model):
    # ..
    customer = models.ForeignKey('register.Customer', db_column='customer')
    # ..

This is other model in other app.

class Customer(models.Model):
    codigo = models.AutoField(primary_key=True)

Both apps are in other database and not of Django.

My settings.py:

DATABASES = {
    'default': {
        'NAME': 'django',
        'ENGINE': 'django.db.backends.mysql',
        'USER': 'my-user',
        'PASSWORD': 'my-password',
        'HOST': '',
        'PORT': ''
    },
    'other-database': {
        'NAME': 'other-database',
        'ENGINE': 'django.db.backends.mysql',
        'USER': 'my-user',
        'PASSWORD': 'my-password',
        'HOST': '',
        'PORT': ''
    }
}

In the HTML I put this:

{{ form_service }}

This my forms.py

from attendance.models import Service
from register.models import Customer
from django.http import HttpResponseRedirect, HttpResponse
from django.core.exceptions import ValidationError

class FormService(ModelForm):

    class Meta:
        model = Service
        fields = ('my_fields', 'my_fields', 'customer')

And this my views.py

def service(request):
    form_service = FormService()
    return render(request, 'service.html', {'form_service': form_service})

I think that the error is here. Perhaps I've had to define my other database, it should select in Django database.

I tried this, but not worked.

def service(request):
    queryset = Customer.objects.using('other-database').all()
    form_service = FormService(instance = queryset)

    return render(request, 'service.html', {'form_service': form_service})

Answer 1

Your code instance = queryset doesn't make sense, because instance should be a Service instance for the form, not a queryset of Customer instances.

Try setting the queryset of the field in the form's __init__ method.

class FormService(ModelForm):
    def __init__(self, *args, **kwargs):
        super(FormService, self).__init__(*args, **kwargs)
        self.fields['customer'].queryset = Customer.objects.using('other-database').all()

    class Meta:
        model = Service
        fields = ('my_fields', 'my_fields', 'customer')

If that doesn't work, please update your question and post the full traceback.