django orm模块中的 is_delete用法

class SystemUserPushHistory(models.Model):
 
  id = models.UUIDField(default=uuid.uuid4, primary_key=True)
  host_name = models.CharField(max_length=128, null=False)
  system_username = models.CharField(max_length=128, null=False)
  method = models.CharField(max_length=32, null=False)
  is_success = models.BooleanField(default=False)
  date_create = models.DateTimeField(auto_now_add=True, editable=False)
  message = models.CharField(max_length=4096, null=True)
 
  class Meta:
    db_table = "assets_systemuser_push_history"
    ordering = ['-date_create']
 
  def __str__(self):
    ret = self.system_username + " => " + self.host_name
    return ret

>>> from django.db.models import Count 
>>> from assets.models import SystemUserPushHistory
>>> p = SystemUserPushHistory.objects.values("host_name").annotate(dcount=Count(1))
>>> p
<QuerySet [{'host_name': '点2', 'dcount': 1}, {'host_name': '点3', 'dcount': 2}, {'host_name': '点2', 'dcount': 1}, {'host_name': '点3', 'dcount': 1}]>
>>> print(p.query)
SELECT `assets_systemuser_push_history`.`host_name`, COUNT(1) AS `dcount` FROM `assets_systemuser_push_history` GROUP BY `assets_systemuser_push_history`.`host_name`, `assets_systemuser_push_history`.`date_create` ORDER BY `assets_systemuser_push_history`.`date_create` DESC