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如何在Django queryset中执行OR条件？

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问题：如何在Django queryset中执行OR条件？
回答 0
回答 1
回答 2

问题：如何在Django queryset中执行OR条件？

我想编写一个与此SQL查询等效的Django查询：

SELECT * from user where income >= 5000 or income is NULL.

如何构造Django queryset过滤器？

User.objects.filter(income__gte=5000, income=0)

这是行不通的，因为它AND是过滤器。我想要OR过滤器以获取单个查询集的并集。

点击查看英文原文

I want to write a Django query equivalent to this SQL query:

SELECT * from user where income >= 5000 or income is NULL.

How to construct the Django queryset filter?

User.objects.filter(income__gte=5000, income=0)

This doesn’t work, because it ANDs the filters. I want to OR the filters to get union of individual querysets.

回答 0

from django.db.models import Q
User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))

通过文档

点击查看英文原文 
from django.db.models import Q
User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))

via Documentation

回答 1

由于QuerySet实现了Python __or__运算符（|）或并集，因此它可以正常工作。正如您所期望的，|二进制运算符返回一个QuerySetso order_by()，，.distinct()其他查询集过滤器可以附加到末尾。

combined_queryset = User.objects.filter(income__gte=5000) | User.objects.filter(income__isnull=True)
ordered_queryset = combined_queryset.order_by('-income')

更新2019-06-20：现在在Django 2.1 QuerySet API参考中已完全记录了该内容。更多历史性讨论可以在DjangoProject票证＃21333中找到。

点击查看英文原文

Because QuerySets implement the Python __or__ operator (|), or union, it just works. As you’d expect, the | binary operator returns a QuerySet so order_by(), .distinct(), and other queryset filters can be tacked on to the end.

combined_queryset = User.objects.filter(income__gte=5000) | User.objects.filter(income__isnull=True)
ordered_queryset = combined_queryset.order_by('-income')

Update 2019-06-20: This is now fully documented in the Django 2.1 QuerySet API reference. More historic discussion can be found in DjangoProject ticket #21333.

回答 2

现有答案中已经提到了这两种选择：

from django.db.models import Q
q1 = User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))

和

q2 = User.objects.filter(income__gte=5000) | User.objects.filter(income__isnull=True)

但是，似乎偏爱哪一个。

关键是它们在SQL级别上是相同的，所以请随意选择您喜欢的任何一个！

在Django的ORM食谱在这个比较详细谈到，这里是有关部分：

queryset = User.objects.filter(
        first_name__startswith='R'
    ) | User.objects.filter(
    last_name__startswith='D'
)

导致

In [5]: str(queryset.query)
Out[5]: 'SELECT "auth_user"."id", "auth_user"."password", "auth_user"."last_login",
"auth_user"."is_superuser", "auth_user"."username", "auth_user"."first_name",
"auth_user"."last_name", "auth_user"."email", "auth_user"."is_staff",
"auth_user"."is_active", "auth_user"."date_joined" FROM "auth_user"
WHERE ("auth_user"."first_name"::text LIKE R% OR "auth_user"."last_name"::text LIKE D%)'

和

qs = User.objects.filter(Q(first_name__startswith='R') | Q(last_name__startswith='D'))

导致

In [9]: str(qs.query)
Out[9]: 'SELECT "auth_user"."id", "auth_user"."password", "auth_user"."last_login",
 "auth_user"."is_superuser", "auth_user"."username", "auth_user"."first_name",
  "auth_user"."last_name", "auth_user"."email", "auth_user"."is_staff",
  "auth_user"."is_active", "auth_user"."date_joined" FROM "auth_user"
  WHERE ("auth_user"."first_name"::text LIKE R% OR "auth_user"."last_name"::text LIKE D%)'

资料来源：django-orm-cookbook

点击查看英文原文

Both options are already mentioned in the existing answers:

from django.db.models import Q
q1 = User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))

and

q2 = User.objects.filter(income__gte=5000) | User.objects.filter(income__isnull=True)

However, there seems to be some confusion regarding which one is to prefer.

The point is that they are identical on the SQL level, so feel free to pick whichever you like!

The Django ORM Cookbook talks in some detail about this, here is the relevant part:

queryset = User.objects.filter(
        first_name__startswith='R'
    ) | User.objects.filter(
    last_name__startswith='D'
)

leads to

In [5]: str(queryset.query)
Out[5]: 'SELECT "auth_user"."id", "auth_user"."password", "auth_user"."last_login",
"auth_user"."is_superuser", "auth_user"."username", "auth_user"."first_name",
"auth_user"."last_name", "auth_user"."email", "auth_user"."is_staff",
"auth_user"."is_active", "auth_user"."date_joined" FROM "auth_user"
WHERE ("auth_user"."first_name"::text LIKE R% OR "auth_user"."last_name"::text LIKE D%)'

and

qs = User.objects.filter(Q(first_name__startswith='R') | Q(last_name__startswith='D'))

leads to

In [9]: str(qs.query)
Out[9]: 'SELECT "auth_user"."id", "auth_user"."password", "auth_user"."last_login",
 "auth_user"."is_superuser", "auth_user"."username", "auth_user"."first_name",
  "auth_user"."last_name", "auth_user"."email", "auth_user"."is_staff",
  "auth_user"."is_active", "auth_user"."date_joined" FROM "auth_user"
  WHERE ("auth_user"."first_name"::text LIKE R% OR "auth_user"."last_name"::text LIKE D%)'

source: django-orm-cookbook