Django对ManyToManyField的查询

Question

class UserProfile(models.Model):
    user = models.ForeignKey(User, unique = True, related_name = 'user')
    likes = models.ManyToManyField(Product, null = True, blank = True)
class Product(models.Model):
    user = models.ForeignKey(User)
    price = models.FloatField(default = 0)

我:

p1 = Product.objects.get(pk = 1)

我想计算在所有UserProfile对象中likes字段中包含p1的次数。

如何?

Answer 1

UserProfile.objects.filter(likes=p1).count()

假设一个产品只能被每个配置文件点赞一次。