Django: "primary_key=True"也指 "unique"吗？

Question

您好，我正在测试Django身份验证和嵌套用户数据。我为用户创建了一个简单的MyProfil模型。我想测试制作自定义的id并将primary_key=True设置为id = models.UUIDField。

models.py

 class MyProfil(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid4, editable=False)
    owner = models.OneToOneField(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    aboutme = models.TextField(max_length=300, blank=True)
    city = models.TextField(max_length=300, blank=True)

到目前为止，一切都对我有利，但是我有一个问题，即使阅读django文档也无法回答自己。

Question

我的primary_key=True字段上的id是否也表示unique或我必须声明它？

Answer 1

是。由于主键是指可以唯一标识对象的值。在the documentation on the primary_key parameter中，我们看到:

Field.primary_key

If True, this field is the primary key for the model.

If you don’t specify primary_key=True for any field in your model, Django will automatically add an AutoField to hold the primary key, so you don’t need to set primary_key=True on any of your fields unless you want to override the default primary-key behavior. For more, see Automatic primary key fields.

primary_key=True implies null=False and unique=True. Only one primary key is allowed on an object.