[Python] Django: Update multiple objects attributes

Is there a more efficient way of do this maybe with F expressions? Some how to reducing hitting the DB?

# 1st way hits DB twice per object
def something():
pks = [4, 2, 1, 3, 0]
for i in range(len(pks)):
mymodel.objects.get(pk=pks).update(attr=i)

# 2nd way hits DB once per obj and once for the queryset
def something():
pks = [4, 2, 1, 3, 0]
order = Case(*[When(pk=pk, then=pos) for pos, pk in enumerate(pks)])
query = mymodel.objects.filter(pk__in=pks).order_by(order)
for i in range(len(query)):
query.attr = i
query.save()


Editing to move variables consistent.

Continue reading...