Django ORM: filter by hour range

问题

I'm trying to implement a filter for hour range, it should returns records with a date between hourA and hourB (ie: "give me the records saved between 16pm and 18pm"). My attempts:

1) Using new 1.6 __hour filter and __in or __range:

MyModel.objects.filter(date__hour__in=(16, 17, 18))
MyModel.objects.filter(date__hour__range=(16, 18))

The code above generates exceptions

2) Using Q objects:

hList = [Q(date__hour=h) for h in (16, 17, 18)]
MyModel.objects.filter(reduce(operator.or_, hList))

This version works, but is very inefficient, since for each hour in the range it repeats the extract() call by generating something like:

   where 
   extract(hour from date) = 16 or 
   extract(hour from date) = 17 or 
   extract(hour from date) = 18

when instead the right raw SQL should be:

where extract(hour from date) in (16, 17, 18)

…how can I filter by hour range in an effective manner, without relying on raw sql?

回答1:

I managed to solve the issue in this way:

    all_points = MyModel.objects.all()
    all_points.extra(where=['extract(hour from MyDateField) in (16, 17, 18)'])

回答2:

In Django 1.9+ you can chain hour lookups, so the examples from the question will work:

MyModel.objects.filter(date__hour__in=(16, 17, 18))
MyModel.objects.filter(date__hour__range=(16, 18))

来源：https://stackoverflow.com/questions/19958391/django-orm-filter-by-hour-range