Models does not create tables when synched

问题

I have some django models for my extended users profile. Problem is that this code does not create tables when syncdb is used (simply nothing happens. No validation errors). Why is that happening? (Also those models give import error elsewhere) :

#!/usr/bin/env python
# encoding: utf-8
from django.db import models
from django.contrib.auth.models import User
from registration.signals import user_registered
from forms import ExtendedRegistrationForm
import hashlib

class InheritedProfile(models.Model):
    first_name = models.CharField("Name", max_length=50, blank=True, null=True)
    last_name = models.CharField("Last name", max_length=50, blank=True, null=True)
    pid = models.CharField("PESEL", max_length=11, blank=True, null=True)
    street = models.CharField("Street", max_length=50, blank=True, null=True)
    number = models.CharField("Flat/house number", max_length=10, blank=True, null=True)
    code = models.CharField("Zip ", max_length=6, blank=True, null=True)
    city = models.CharField("City", max_length=50, blank=True, null=True) 
    class Meta:
        abstract=True

class UserProfile(InheritedProfile):
    def upload_path(self, field_attname):
        filename = hashlib.md5(field_attname).hexdigest()[:4] + "_" + field_attname
        return "uploads/users/%s" % (filename,)

    user = models.ForeignKey(User, unique=True, related_name='profile')
    image = models.ImageField(upload_to=upload_path, verbose_name="Image", blank=True, null=True)

    class Meta:
        ordering = ['-id']
        db_table = 'userprofile'

    def __unicode__(self):
        return u"%s " % self.user.username

def user_created(sender, user, request, **kwargs):
    form = ExtendedRegistrationForm(request.POST)
    extended_user = UserProfile(user=user)
    extended_user.is_active = False
    extended_user.first_name = form.cleaned_data['first_name']
    extended_user.last_name = form.cleaned_data['last_name']
    extended_user.pid = form.cleaned_data['pid']
    extended_user.image = form.cleaned_data['image']
    extended_user.street = form.cleaned_data['street']
    extended_user.number = form.cleaned_data['number']
    extended_user.code = form.cleaned_data['code']
    extended_user.city = form.cleaned_data['city']
    extended_user.save()

user_registered.connect(user_created)

class Friend(InheritedProfile):
    friend_of = models.ForeignKey(UserProfile, related_name='friend_of')
    class Meta:
        db_table = 'friend'

In contrary this code produces tables flawlessly :

#!/usr/bin/env python
# encoding: utf-8
from django.db import models
from django.contrib.auth.models import User
import hashlib

class InheritedProfile(models.Model):
    first_name = models.CharField("Name", max_length=50, blank=True, null=True)
    last_name = models.CharField("Last name", max_length=50, blank=True, null=True)
    pid = models.CharField("PESEL", max_length=11, blank=True, null=True)
    street = models.CharField("Street", max_length=50, blank=True, null=True)
    number = models.CharField("Flat/house number", max_length=10, blank=True, null=True)
    code = models.CharField("Zip ", max_length=6, blank=True, null=True)
    city = models.CharField("City", max_length=50, blank=True, null=True) 
    class Meta:
        abstract=True

class UserProfile(InheritedProfile):
    def upload_path(self, field_attname):
        filename = hashlib.md5(field_attname).hexdigest()[:4] + "_" + field_attname
        return "uploads/users/%s" % (filename,)

    user = models.ForeignKey(User, unique=True, related_name='profile')
    image = models.ImageField(upload_to=upload_path, verbose_name="Image", blank=True, null=True)

    class Meta:
        ordering = ['-id']
        db_table = 'userprofile'

    def __unicode__(self):
        return u"%s " % self.user.username

class Friend(InheritedProfile):
    friend_of = models.ForeignKey(UserProfile, related_name='friend_of')
    class Meta:
        db_table = 'friend'

Should I move this user_created function somewhere else ? Signals shouldn't create problems here...

回答1:

Well you seem to have some kind of cross import; if you import some models to forms and some form from there back to models this can't be resolve, because when processing models forms is required to be imported, and forms requires models again... This can't be resolved!

Besides this I think it's better design not needing to import forms in a models module, because they are more related to views!

来源：https://stackoverflow.com/questions/3124052/models-does-not-create-tables-when-synched