#27496: Iterating over ModelChoiceField with RadioSelect widget duplicates query
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               Reporter:  a-p-f       |          Owner:  nobody
                   Type:  Bug         |         Status:  new
              Component:  Forms       |        Version:  1.10
               Severity:  Normal      |       Keywords:
           Triage Stage:  Unreviewed  |      Has patch:  0
    Needs documentation:  0           |    Needs tests:  0
Patch needs improvement:  0           |  Easy pickings:  0
                  UI/UX:  0           |
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 If you have a form with a ModelChoiceField using a RadioSelect widget and
 iterate over the individual radio inputs in your template (as demonstrated
 in the docs-
 https://docs.djangoproject.com/en/1.10/ref/forms/widgets/#radioselect),
 then the field's queryset will be evaluated for each option. Actually, the
 query seems to be executed 2n + 5 times, where n is the number of objects
 returned by the queryset.

 To reproduce this, use the following code with any model and watch your
 database server logs.

 {{{#!python
 class BugTestForm(forms.Form):
     choice = forms.ModelChoiceField(queryset=MyModel.objects.all(),
 widget=forms.RadioSelect)

 form = BugTestForm()
 list(form['choice'])
 }}}

 The same issue occurs when using ModelMultipleChoiceField with a
 CheckboxSelectMultiple widget.

--
Ticket URL: <https://code.djangoproject.com/ticket/27496>
Django <https://code.djangoproject.com/>
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