defer_example.py

# retrieving products with all fields
%timeit Product.objects.all()                                                                                                                                                                                                                        
6.08 µs ± 97.2 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)


# fetching products after deferring name and category
%timeit Product.objects.defer('name', 'category')                                                                                                                                                                                                   
14.4 µs ± 103 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)


# more about using 'defer()'

# defers both name and attributes columns
Product.objects.defer("name").filter(stock__gt=5).defer("attributes")

# defer also works on related object fields
Product.objects.select_related().defer("category__created_by")