OK, thanks for sharing this On 16 Apr, 07:54, Pavan Verma <pavan.ve...@gmail.com> wrote: > I am a Django newbie and also interested in this question. > > From reading the Django bookhttp://www.djangobook.com/en/2.0/chapter05/, > I see that the query 'Publisher.objects.order_by('name')[0:2]' maps > to: > > SELECT id, name, address, city, state_province, country, website > FROM books_publisher > ORDER BY name > OFFSET 0 LIMIT 2; > > Also, Django delays execution of the db query until the result is > actually required. > > Given the above two observations, I would think that both the type of > accesses you mentioned will do exactly the same thing, which is to do > a query with "OFFSET 0 LIMIT 1". > > To confirm this, you can use the django-devserver (https://github.com/ > dcramer/django-devserver) with SQL queries enabled which will display > every query made in real time. > > thanks, > -pavan > > On Apr 14, 9:56 pm, NENAD CIKIC <nenad.ci...@gmail.com> wrote: > > > > > > > > > Hello! > > I want to get just the top element of one queryset. SO I have > > something as > > qs=MyModel.objects.filter(...).order_by(..) > > > and then use qs[0] and check some value > > > I wonder now if i did the right thing or it is better to use .extra on > > queryset. > > Is the queryset object allocated for all objects, or is django/python > > smarter than me and gets only the needed object? > > > Should I maybe do directly > > topObj=MyModel.objects.filter(...).order_by(..)[0] > > > What is better? > > Thanks > > Nenad
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