python - 如何在不使用 for 循环的情况下在多对多字段上应用过滤器

Question

我的模型就像

class Company(models.Model):
    name = models.CharField(max_length=400, blank=True, null=True)

class Intership(models.Model):
    company = models.ForeignKey(Company)
    location = models.CharField(max_length=400, blank=True, null=True)


class Student(models.Model):
    name = models.CharField(max_length=400, blank=True, null=True)
    intership = models.ManyToManyField(Intership,null= True, blank=True)

我期待所有在名为“xyz”的公司实习过的学生。

我有代码

company_name = "xyz"
stds
for student in students:
    interships = student.intership.all()
    for intership in interships:
        if intership.company.name == company_name:
            stds.append(student)

是否可以通过一次查询获得所有这些信息？

Answer 1

您可以只过滤 Student s 本身:

Student.objects.filter(<b>intership__company__name=<i>'xyz'</i></b>)

您可能想使用.distinct()在这里，否则 Student在同一家公司的多个实习机会将被多次列出:

Student.objects.filter(intership__company__name=<i>'xyz'</i>)<b>.distinct()</b>

Note: It is inter<b>n</b>ship, not intership.