Python 姜戈错误。不能分配必须是一个实例
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Django error. Cannot assign must be an instance
提问by rahimbah
I get the following error when I try to run an insert into one of my tables.
当我尝试在我的一个表中运行插入时出现以下错误。
Cannot assign "1": "Team.department_id" must be a "Department" instance
无法分配“1”：“Team.department_id”必须是“Department”实例
Admittedly I'm slightly unsure if I'm using the foreign key concept correctly. The insert I'm trying to run and a snippet from my models.py are given below.
诚然，我有点不确定我是否正确使用了外键概念。下面给出了我尝试运行的插入和来自我的 models.py 的片段。
What I'm trying to do is that when someone wants to create a new team. They have to attach it to a department. Therefore the department ID should be in both sets of tables.
我想做的是当有人想要创建一个新团队时。他们必须将它附加到一个部门。因此部门 ID 应该在两组表中。
new_team = Team(
nickname = team_name,
employee_id = employee_id,
department_id = int(Department.objects.get(password = password, department_name = department_name).department_id)
)
models.py
模型.py
class Department(models.Model):
department_id = models.AutoField(auto_created=True, primary_key=True, default=1)
department_name = models.CharField(max_length=60)
head_id = models.CharField(max_length=30)
password = models.CharField(max_length=128)
class Team(models.Model):
team_id = models.AutoField(primary_key=True)
department_id = models.ForeignKey('Department', related_name = 'Department_id')
employee_id = models.CharField(max_length=30)
nickname = models.CharField(max_length=60)
team_image = models.ImageField(upload_to=get_image_path, blank=True, null=True)
回答by Anonymous
You don't need to pass the department id, the instance itself is enough. The following should work just fine:
您不需要传递部门 ID，实例本身就足够了。以下应该可以正常工作：
new_team = Team(
nickname = team_name,
employee_id = employee_id,
department_id = Department.objects.get(password = password, department_name = department_name)
)
Just a note, don't ever name your foreign fields something_id. That somethingis enough. Django is meant to make things easy from the user's perspective and the _idsuffix means you're thinking of the database layer. In fact, if you named your column department, django will automatically create department_idcolumn in the database for you. The way things are, you're making django create department_id_idwhich is rather silly.
只是注意，不要老是命名洋田东西_id。那东西就够了。从用户的角度来看，Django 旨在使事情变得简单，_id后缀意味着您正在考虑数据库层。事实上，如果你给你的 column 命名department，django 会自动department_id为你在数据库中创建column 。事情就是这样，你让 django createdepartment_id_id这是相当愚蠢的。
