Question

考虑这两个模型：

class pm_thread(models.Model):
    subject = models.CharField(max_length=200)
    participants = models.ManyToManyField(User)

    def latest_message(self):
        message = self.message_set.order_by('-datetime')
        if message:
            return message[0]
        return None

class pm_message(models.Model):
    thread = models.ForeignKey(pm_thread, related_name='message_set')
    user = models.ForeignKey(User, related_name='sent_message')
    datetime = models.DateTimeField(auto_now_add=True)
    content = models.TextField()

如何在最新消息日期之前订购pm_thread查询？例如：

threads = pm_thread.objects.filter(participants=request.user).order_by(latest_message.datetime)

Answer 1

尝试：

threads = pm_thread.objects.filter(participants=request.user).order_by('-pm_message__datetime')

通过反向ForeignKey DateTimeField排序？

1 个答案: