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34 lines
789 B
Python
34 lines
789 B
Python
from django.db import models
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class Entity(models.Model):
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pass
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class Country(Entity):
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name = models.CharField(max_length=30)
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class EUCountry(Country):
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join_date = models.DateField()
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class City(models.Model):
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name = models.CharField(max_length=30)
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country = models.ForeignKey(Country, models.CASCADE)
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class EUCity(models.Model):
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name = models.CharField(max_length=30)
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country = models.ForeignKey(EUCountry, models.CASCADE)
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class Person(models.Model):
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name = models.CharField(max_length=30)
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born = models.ForeignKey(City, models.CASCADE, related_name='+')
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died = models.ForeignKey(City, models.CASCADE, related_name='+')
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class PersonProfile(models.Model):
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person = models.OneToOneField(Person, models.CASCADE, related_name='profile')
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