在django中的条件下添加一列

Question

这是我的模型

class User_quiz_logs(models.Model):
    user_id = models.ForeignKey(User, on_delete=models.CASCADE, null=False)
    user_quiz_id = models.AutoField(primary_key=True)
    response = models.CharField('response ', max_length=300, null=False)
    points = models.IntegerField('points', null=True)
    state_quiz = models.BooleanField('state', default=False)

有对应同一个人的属性点要加吗？

例子

1   A   1   true    141
2   A   1   true    141
3   A   1   true    141
4   B   5   true    165
5   C   1   true    165

id 141 的人他的积分总和为 3，id 165 的总积分为 6。

Answer 1

您可以 .annotate(…) ^[Django-doc] 使用：

from django.db.models import <b>Q, Sum</b>

User.objects.annotate(
    <b>points=Sum('user_quiz_logs__points', filter=Q(user_quiz_logs__state_quiz=True))</b>
)

由此QuerySet产生的User对象将有一个额外的属性.points，它将包含相关[=15]的points的总和=] 那个 User.

Note: Models in Django are written in PascalCase, not snake_case, so you might want to rename the model from ~~User_quiz_logs~~ to UserQuiz.

Note: It is normally better to make use of the settings.AUTH_USER_MODEL ^[Django-doc] to refer to the user model, than to use the User model ^[Django-doc] directly. For more information you can see the referencing the User model section of the documentation.

Note: Normally one does not add a suffix _id to a ForeignKey field, since Django will automatically add a "twin" field with an _id suffix. Therefore it should be user, instead of ~~user_id~~.

在django中的条件下添加一列

add a column under a condition in django

python

django

django-models