Django的ORM中如何判断查询结果是否为空，判断django中的orm为空

result= Booking.objects.filter()

#方法一 .exists()
if result.exists():
print "QuerySet has Data"
else:
print "QuerySet is empty"
#方法二 .count()==0
if result.count() == 0:
print "empty"
#方法三
if result:
print "QuerySet has Data"
else:
print "QuerySet is empty"

总结：
QuerySet.exists() > QuerySet.count()==0 > QuerySet