python - Django 在单个查询集中组合外键

Question

我在 Django 应用程序中有一个模型被多个其他模型引用为外键。

我正在寻找一种方法来为此类的所有对象创建单个查询集，这些对象根据某些条件被其他类引用为 ForeignKey。

我什至不确定这是否可能，但我还是想问问。

class Person(models.Model):
    pass


class Book(models.Model):
    year_published = models.PositiveIntegerField()
    author = models.ForeignKey(Person)


class MusicAlbum(models.Model):
    year_published = models.PositiveIntegerField()
    producer = models.ForeignKey(Person)

recent_books = Book.objects.filter(year_published__gte=2018)
recent_music_albums = MusicAlbum.objects.filter(year_published__gte=2018)

# How can I create a **single** queryset of the Person objects that are being referenced as `author` in `recent_books` and as `producer` in `recent_music_albums`?

感谢您的宝贵时间。

Answer 1

目前我面前没有 Django，但是像这样的东西呢:

class Person(models.Model):
    pass


class Book(models.Model):
    year_published = models.PositiveIntegerField()
    author = models.ForeignKey(Person, related_name='books')


class MusicAlbum(models.Model):
    year_published = models.PositiveIntegerField()
    producer = models.ForeignKey(Person, related_name='albums')

Person.objects.filter(books__year_published__gte=2018, albums__year_published__gte=2018)

或者，如果您无论如何都必须执行前两个查询，

Person.objects.filter(books__in=recent_books, albums__in=recent_music_albums)