Question

我要建立一个资产管理系统。每个属性都有一个独特的属性 - 代码与部门代码和类型代码相结合。

from django.db import models


class Department(models.Model):
    # department_code like rm01
    department_code = models.CharField(max_length=4, unique=True)
    name = models.CharField(max_length=100)


class Type(models.Model):
    # type_code like fe03
    type_code = models.CharField(max_length=4, unique=True)
    name = models.CharField(max_length=100)


class Property(models.Model):
    # property_code like rm01fe037767
    property_code = models.CharField(max_length=12, unique=True)
    name = models.CharField(max_length=100)
    department = models.ForeignKey(Department)
    type = models.ForeignKey(Type)

怎么做？或者是否有其他方法可以实现目标？

Answer 1

是，但不是自动。

在正常情况下：当你想添加新的Propery~＆gt;用户应该选择其他2个型号吗？

dep_id = ?
type_id= ?
p = Property (id = dep_id+type_id, name = "blabla"...)
p.save()
And you should define the PK (default is int field, auto incre ~> to charfield) and input it by yourself

通常情况下：我们不这样做......

我们使用：ForeignKey如：

class Item(models.Model):
    people = models.ForeignKey(People)
    name = models.CharField(max_length=40)
    value = models.IntegerField(default=0)
    def __str__(self):
        return self.name

如何自动添加字段

1 个答案: