django prefetch when listing objects in admin

django, django-admin, django-forms

Solution

I figured out one way to do this:

class TicketAdminForm(forms.ModelForm):
  class Meta:
    model = Ticket
  userinfo = forms.ModelChoiceField(queryset=UserInfo.objects.prefetch_related('user').all())

class TicketAdmin(admin.ModelAdmin):
  form = TicketAdminForm

admin.site.register(Ticket, TicketAdmin)

Now the needed models are prefetched as a one sql query rather than many queries.

Problem

I have following models: ``` class UserProfile(models.Model): name = models.CharField() info = models.OneToOneField(UserInfo, related_name='user') class UserInfo(models.Model): def __unicode__(self): return self.user.__unicode__() + self.age age = models.IntegerField() class Ticket(models.Model): userinfo = models.ForeignKey(UserInfo) ``` The problem is now in the Ticket admin interface. Ticket's userinfo field is rendered as dropdown. If there is lots of UserInfo in the database, every one of them makes a single call to the database (UserProfile) to generate its name. How can I tell the admin (or any widget) to prefetch related UserProfiles when it is rendering the UserInfo dropdown? I am looking for something like ``` info = models.OneToOneField(UserInfo, related_name='user', prefetch_in_bulk=True) ```

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