Django F() division - How to avoid rounding off

Question

I have this code:

q = MyModel.objects.order_by(\'-value1\').annotate(
            res=ExpressionWrapper(
                (F(\'value1\') / F(\'value2\')), 
               


        

Answer 1

Simply make use of F()'s support for multiplication to convert one factor to decimal number.

Combined expression then would look like:

from decimal import Decimal

q = MyModel.objects.order_by('-value1').annotate(
            res=ExpressionWrapper(
                (F('value1') * Decimal('1.0') / F('value2')), 
                output_field=FloatField()),
            )

I find this more elegant way then write raw SQL CAST on value1 field and then do the division.