Friday, January 21, 2022

Re: order_by on the basis of time difference (updated_at - created_at)

this can be easily solved by using an annotation to calculate the difference and store it in a new temporary column, and then sort by it


from django.db.models import F
from myapp.models import ExampleModel

queryset = ExampleModel.objects.annotate(
    dt_difference=F('updated_at') - F('created_at')
).order_by('dt_difference')

for example in queryset[:10]:
    print(f'created_at={example.created_at} - updated_at={example.updated_at} - dt_difference={example.dt_difference}')



Em sex., 21 de jan. de 2022 às 10:54, Gabriel Araya Garcia <gabrielaraya2011@gmail.com> escreveu:
Try this:
ExampleModel.objects.all().order_by('updated_at' , '-created_at')
Gabriel Araya Garcia
GMI - Desarrollo de Sistemas Informáticos




El vie, 21 ene 2022 a las 1:54, Aadil Rashid (<aadil10121998@gmail.com>) escribió:
class ExampleModel(models.Model):
is_active = models.BooleanField(default=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)



I want to query on UserModel such that the Query set which I get should be orderable in terms of time difference of updated_at - created_at,
I tried
ExampleModel.objects.all().order_by('updated_at' - 'created_at')
but this is not working
it throws, TypeError: unsupported operand type(s) for -: 'str' and 'str'


Django Family Please Help...................

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