我会简单地添加一个状态，但判断是否使用了结束时间戳.通过定义一个字段status，你引入了data duplication，你指定了同样的东西twice.

您可能还应该combine日期和时间，因为时间戳不仅仅是日期和时间，例如daylight saving time.

from django.conf import settings


class Auction(models.Model):
    auction_id = models.AutoField(primary_key=True)
    crop = models.ForeignKey(Crop, on_delete=models.CASCADE)
    image = models.ImageField(upload_to='crop-image')
    farmer = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        limit_choices_to={'user_type': 'farmer'},
    )
    creation_time = models.DateTimeField(auto_now_add=True)
    end_timestamp = models.DateTimeField()
    # no status
    qty = models.IntegerField()
    unit = models.CharField(
        max_length=10,
        choices=[
            ('kg', 'Kilograms'),
            ('tonne', 'Metric Tons'),
            ('bushel', 'Bushels'),
            ('crate', 'Crates'),
        ],
    )
    hammer_price = models.IntegerField()
    description = models.CharField(max_length=200)
    payment = models.BooleanField(default=False)

    class Meta:
        verbose_name_plural = 'Auctions'

    def __str__(self):
        return self.crop.title

例如，我们可以获得所有仍然活跃的Auction:

from django.db.models.functions import Now

Auction.objects.filter(end_timestamp__gte=Now())

现在，我们以passive种方式确定状态，这通常比主动改变状态的进程更可靠.

我们可以通过设置db_index=True ^[Django-doc]来提高性能.

Note:通常使用settings.AUTH_USER_MODEL ^[Django-doc]来引用用户模型比直接使用User model ^[Django-doc]更好.更多信息可以看referencing the User model section of the documentation ^[Django-doc].