Django获取具有外键的对象

Question

I'm creating an article app (in django) where articles can have images. I want to get articles only when they have at least one image. I already tried:

Article.objects.all().annotate(num_extra=Count("Image")).order_by("-num_extra")

But that only returned a sorted queryset starting with the most images and thats not wat I want. Is there a way to do that?

My models.py

class Article(models.Model):
    id = models.CharField(max_length=8, default=None, primary_key=True, blank=True, verbose_name="ID", unique=True, editable=False)
    Category = models.ForeignKey(Category, default=None, on_delete=models.CASCADE, verbose_name="Kategorie")
    text = models.CharField(max_length=678543)
    #And some other fields
class Image(models.Model):
    Article = models.ForeignKey(Article, on_delete=models.CASCADE, default=None, verbose_name="Artikel")
    authors = models.ManyToManyField(User, verbose_name="Autor", default=None, blank=True)
    #And some other fields

Answer 1

您可以过滤图像中不存在Image尝试以下操作：

Article.objects.filter(image__isnull=False)