I know the short answer because I tried it. Is there any way to accomplish this though (even if only on account of a hack)?
class Ticket(models.Model):
account = modelfie开发者_运维知识库lds.AccountField()
uuid = models.CharField(max_length=36, unique=True)
created = models.DateTimeField(auto_now_add=True)
class Meta:
ordering = ['created']
@property
def repair_cost(self):
# cost is a @property of LineItem(models.Model)
return self.lineitem_set.aggregate(models.Sum('cost'))
No. Anything that goes through a built-in manager has to be a real field, since they only touch the database. In order to work with a property they'd have to turn every record in the table into a model, then filter through them in Python.
I have a similar scenario and want exactly the same feature. I solved it trivially with the following line:
...
return sum(lt.cost for lt in self.lineitem_set)
can use django-queryable-properties
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