Slice on Django Model Queryset -

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i try run query paged results, model.objects.all()[start: start+page_size].

i want know whether there more pages load, say, want know whether start+page_size < model.objects.all().count().

my question is, if call all() twice here, whether django executes same query twice (one slice operation[], 1 count()).

another question if slice on model.objects.all() model.objects.all()[2:9] whether django fetch data db , slice python, or django fetch sql limit limit 2 9

yes, makes 2 queries, these not "same query" @ all. 1 select * mymodel limit <page_size> offset <start> , other select count(*) mymodel.

if want avoid 2 queries, simple fix ask 1 more record need:

model.objects.all()[start: start+page_size+1]

then can iterate page_size, , show next button if record there.


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