python – 从一个庞大且不断增长的数据集中优化慢速django查询集

注意我是一个django noob并且还没有完全包围我的模型.Manager和model.query.QuerySet所以如果这个设置看起来很尴尬….

目前,页面加载查询集大约需要18秒,目前只有大约500条记录.每天平均会有大约100条新记录.

该数据库是Postgresql

慢视图：

def approvals(request):
    ...
    approved_submissions = QuestSubmission.objects.all_approved()
    ...

慢查询集：

class QuestSubmissionQuerySet(models.query.QuerySet):
    ...

    def approved(self):
        return self.filter(is_approved=True)

    def completed(self):
         return self.filter(is_completed=True).order_by('-time_completed')

    ...

class QuestSubmissionManager(models.Manager):
    def get_queryset(self):
        return QuestSubmissionQuerySet(self.model,using=self._db)

    def all_approved(self,user=None):
        return self.get_queryset().approved().completed()

    ...

从QuestSubmission.objects.all_approved()得到的SQL：

'SELECT "quest_manager_questsubmission"."id","quest_manager_questsubmission"."quest_id","quest_manager_questsubmission"."user_id","quest_manager_questsubmission"."ordinal","quest_manager_questsubmission"."is_completed","quest_manager_questsubmission"."time_completed","quest_manager_questsubmission"."is_approved","quest_manager_questsubmission"."time_approved","quest_manager_questsubmission"."timestamp","quest_manager_questsubmission"."updated","quest_manager_questsubmission"."game_lab_transfer" FROM "quest_manager_questsubmission" WHERE ("quest_manager_questsubmission"."is_approved" = True AND "quest_manager_questsubmission"."is_completed" = True) ORDER BY "quest_manager_questsubmission"."time_completed" DESC'

缓慢的模型：

class QuestSubmission(models.Model):
    quest = models.ForeignKey(Quest)
    user = models.ForeignKey(settings.AUTH_USER_MODEL,related_name="quest_submission_user")
    ordinal = models.PositiveIntegerField(default = 1,help_text = 'indicating submissions beyond the first for repeatable quests')
    is_completed = models.BooleanField(default=False)
    time_completed = models.DateTimeField(null=True,blank=True)
    is_approved = models.BooleanField(default=False)
    time_approved = models.DateTimeField(null=True,blank=True)
    timestamp = models.DateTimeField(auto_now=True,auto_now_add=False)
    updated = models.DateTimeField(auto_now=False,auto_now_add=True)
    game_lab_transfer = models.BooleanField(default = False,help_text = 'XP not counted')

    class Meta:
        ordering = ["time_approved","time_completed"]

    objects = QuestSubmissionManager()

    #other methods
    ....

有哪些策略可以解决这个问题？我尝试使用django的Paginator,但它似乎只显示在页面中,但它仍然加载整个查询集.