How can I get build a QuerySet that gets multiple rows from django? I thought filter() would work, but it seems to be worse off.
For example, I have two rows in the model Car, with two text attributes (license and vin). Now say I want to print the licenses and vins from these cars. How can I do that with one database call?
Here's an answer that will make two database calls:
#using get(), two total queries
a = Car.objects.get(id=1) #query here
b = Car.objects.get(id=2) #query here
print(a.license + a.vin) #no query
print(b.license + b.vin) #no query
That obviously didn't work because I made two get() queries. So next I'll try filter():
#using filter(), four total queries
c = Car.objects.filter(id__in=(1,2)) #no query
print(c[0].license + c[0].vin) #two queries
print(c[1].license + c[1].vin) #two queries
Hmmm, that's weird, why is making four database calls? Is there a way I can make it get the two in one database call?