我想在django对面查询吗？

Question

Eg I have the models

class Question(models.Model):
    question = models.CharField(max_length="200")

class Answer(models.Model):
    question= models.ForeignKey(Question)

So, I want all Question's that I don't have in Answers

Eg In answer I have

Question 1
Question 2

and in Question I have

Question 1
Question 2
Question 3
Question 4

and I want like result of my Query Question 3 and Question 4

thanks

Answer 1

我认为您想要的是：

unanswered_questions = Question.objects.filter(answer__isnull=True)

Answer 2

The easiest way is to first get a distinct list of all question IDs in Answer, then get all Questions that do not have one of those IDs

ids = Answer.objects.all().distinct().values_list('question', Flat=True)
unanswered = Question.objects.all().exclude(pk__in=ids)