Django Order By Query on Methods in Models -

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i have model:

class user(models.model):   uid = models.autofield(primary_key=true)   email = models.emailfield(max_length=200, unique=true)   password = models.charfield(max_length=200)   name = models.charfield(max_length=200, default='')   contact = models.charfield(max_length=10)   cash_amount = models.integerfield(default=25000)   share_amount = models.integerfield(default=0)   def __str__(self):     return self.email   def total_amount(self):     return self.cash_amount + self.share_amount

how write queryset ordering result on basis of total_amount(), tried below query:

user.objects.order_by('total_amount()')

but fielderror: invalid order_by arguments: ['total_amount()'] comes.

is there other way possible of writing query ordering result on basis of cash_amount + share_amount without creating total_amount().

you can try using extra

user.objects.extra(     select={'field_sum' : 'cash_amount + share_amount'},     order_by=('field_sum',) )

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