Yes!! Here you have an example 👇
You can use QuerySet.prefetch_related or QuerySet.select_related with Abstract Base Classes in Django.
Let's say we have these models:
class Country(models.Model):
name = models.CharField(max_length=200)
def __str__(self):
return self.name
class AbstractPerson(models.Model):
first_name = models.CharField(max_length=30)
last_name = models.CharField(max_length=30)
class Meta:
abstract = True
class AbstractAddress(models.Model):
street = models.CharField(max_length=100)
city = models.CharField(max_length=50)
state = models.CharField(max_length=2)
zip_code = models.CharField(max_length=10)
country = models.ForeignKey(Country, on_delete=models.CASCADE)
class Meta:
abstract = True
class AbstractPhoneNumber(models.Model):
phone_number = models.CharField(max_length=15)
class Meta:
abstract = True
class Contact(AbstractPerson, AbstractAddress, AbstractPhoneNumber):
email = models.EmailField()
def __str__(self):
return f"{self.first_name} {self.last_name} - {self.country}"
If you make this query you wouldn't have a N+1 issue:
> Contact.objects.select_related("country").get(id=1).country
You have one query only. The generated SQL is:
SELECT app_contact.id,
app_contact.first_name,
app_contact.last_name,
app_contact.street,
app_contact.city,
app_contact.state,
app_contact.zip_code,
app_contact.country_id,
app_contact.phone_number,
app_contact.email,
app_country.id,
app_country.name
FROM app_contact
INNER JOIN app_country
ON (app_contact.country_id = app_country.id)
WHERE app_contact.id = '1'
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