python - Unexpected behaviour in django queryset -


i have following code:

foo_list = foo.objects.all()[100:200] print foo_list[0].id print len(foo_list) print foo_list[0].id

i expect result of first , third print eqaul not.how happen?

you're running "wontfix" issue @ https://code.djangoproject.com/ticket/9006 --

limit queries without order aren't guaranteed return consistent result sets

(depending on underlying db engine), , that's [0] indexing causing happen -- because despite misleading name foo_list not list, it's queryset itself! documented @ https://docs.djangoproject.com/en/1.7/ref/models/querysets/ ,

slicing unevaluated queryset returns unevaluated queryset

solution: make list:

foo_list = list(foo.objects.all()[100:200])

and live happily ever after:-)


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