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    <p>I tried something similar to Izz ad-Din Ruhulessin's suggestion but it didn't work because I have columns other than the "fake FK" column. The code I tried was:</p> <pre><code>class DynamicPkg(models.Model): @property def cities(self): return City.objects.filter(dpdestinations__dynamic_pkg=self) class DynamicPkgDestination(models.Model): dynamic_pkg = models.ForeignKey(DynamicPkg, related_name='destinations') # Indexed because we will be joining City.code to # DynamicPkgDestination.city_code and we want this to be fast. city_code = models.CharField(max_length=10, db_index=True) class UnmanagedDynamicPkgDestination(models.Model): dynamic_pkg = models.ForeignKey(DynamicPkg, related_name='destinations') city = models.ForeignKey('City', db_column='city_code', to_field='code', related_name='dpdestinations') class Meta: managed = False db_table = DynamicPkgDestination._meta.db_table class City(models.Model): code = models.CharField(max_length=10, unique=True) </code></pre> <p>and the errors I got were:</p> <pre><code>Error: One or more models did not validate: travelbox.dynamicpkgdestination: Accessor for field 'dynamic_pkg' clashes with related field 'DynamicPkg.destinations'. Add a related_name argument to the definition for 'dynamic_pkg'. travelbox.dynamicpkgdestination: Reverse query name for field 'dynamic_pkg' clashes with related field 'DynamicPkg.destinations'. Add a related_name argument to the definition for 'dynamic_pkg'. travelbox.unmanageddynamicpkgdestination: Accessor for field 'dynamic_pkg' clashes with related field 'DynamicPkg.destinations'. Add a related_name argument to the definition for 'dynamic_pkg'. travelbox.unmanageddynamicpkgdestination: Reverse query name for field 'dynamic_pkg' clashes with related field 'DynamicPkg.destinations'. Add a related_name argument to the definition for 'dynamic_pkg'. </code></pre> <p>However I did come up with a working solution by using a proxy model. I did still have to hack around some Django validation that prevents fields from being included in proxy models:</p> <pre><code>class DynamicPkg(models.Model): @property def cities(self): return City.objects.filter(dpdestinations__dynamic_pkg=self) def proxify_model(new_class, base): """ Like putting proxy = True in a model's Meta except it doesn't spoil your fun by raising an error if new_class contains model fields. """ new_class._meta.proxy = True # Next 2 lines are what django.db.models.base.ModelBase.__new__ does when # proxy = True (after it has done its spoil-sport validation ;-) new_class._meta.setup_proxy(base) new_class._meta.concrete_model = base._meta.concrete_model class DynamicPkgDestination(models.Model): dynamic_pkg = models.ForeignKey(DynamicPkg, related_name='destinations') # Indexed because we will be joining City.code to # DynamicPkgDestination.city_code and we want this to be fast. city_code = city_code_field(db_index=True) class ProxyDynamicPkgDestination(DynamicPkgDestination): city = models.ForeignKey('City', db_column='city_code', to_field='code', related_name='dpdestinations') proxify_model(ProxyDynamicPkgDestination, DynamicPkgDestination) class City(models.Model): code = models.CharField(max_length=10, unique=True) </code></pre>
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    1. COYour problem is using: related_name='destinations' for both ForeignKeys use managed_destinations and unmanaged_destinations for each respectively.
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      1. USAaron McMillin
 

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