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copied!<p>To do exactly what you're describing:</p> <blockquote> <p>I am trying to create a database relationship where CarMaunfacturer has many VehicleNames and also TruckManufacturer has many VehicleNames</p> </blockquote> <p>You'd create a nullable foreign key on VehicleName to both of your Manufacturer models:</p> <pre><code>class CarManufacturer(models.Model): # field definitions here class TruckManufacturer(models.Model): # field definitions here class VehicleName(models.Model): car_manufacturer = models.ForeignKey(CarManufacturer, blank=True, null=True) truck_manufacturer = models.ForeignKey(TruckManufacturer, blank=True, null=True) </code></pre> <p>Then, instances of <code>CarManufacturer</code> or <code>TruckManufacturer</code> can get the names via the <code>vehiclename_set</code> attribute.</p> <p>For a more advanced design, I would probably try to abstract the shared manufacturer behavior into a single model, then use multi-table inheritance:</p> <pre><code>class Manufacturer(models.Model): # shared car and truck manufacturer fields go here class CarManufacturer(Manufacturer): # car manufacturer specific fields go here class TruckManufacturer(Manufacturer): # truck manufacturer specific fields go here class VehicleName(models.Model): manufacturer = models.ForeignKey(Manufacturer) </code></pre> <p>See the <a href="https://docs.djangoproject.com/en/dev/topics/db/models/#multi-table-inheritance" rel="nofollow">multi-table inheritance docs</a> for full details.</p>

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