显示来自 Model Django 的唯一值的表格

Question

Learning Django.. I am trying to setup the below and need your expert advise to make it better..

I created a model, and form on top of it to show the data.. and I have two questions after the code where I need your advise:)

Model:

class profilestable(models.Model):
   choices = [
   ('Active','Active'),
   ('Inactive','Inactive')
   ]
   Category = models.CharField(max_length=100)
   SubCategory = models.CharField(max_length=100)
   product_name = models.CharField(max_length=100)
   Status = models.ChoiceField(max_length=20,choices=choices)

   def __str__(self):
      return self.Category

class Userlist(models.Model):
       User = models.CharField(max_length=100)
       Categorygroup = models.ForeignKey(profilestable,null=true,on_delete=models.SET_NULL)
    
       def __str__(self):
          return self.User

Form:

class userprofileform(forms.ModelForm):
   model = Userlist
   Fields = ('User','CategoryGroup')

def __init__(self,*args,**kwargs):
   super(userprofileform,self).__init__(*args,**kwargs)

Sample data in the profilestable Model:

Queries:

1. I want to add the category, subcategory and product name as drop downs to the form however I am not sure how to access each element to show on the form. I was able to pull only category since I am returning that value.
2. The list currently has lots of duplicate values, is it possible to show only unique values in the drop down.
3. Also, is it possible to make it a multi-select and dependent cascading drop downs

Request you to please help advise/direct to implement this type of form.

Thank you so much.

Answer 1

The structure needs some changes, for example category should be a parent of sub-category , and then product lives below sub-category , so it would be better to create a separates models for Category , Sub-category and Product in this relation:

Category > Sub-category > Product Since sub-category and products are not unique relation to its parent, use the ForeignKey Field to connect them.

Also I see in your sample data and many products are shinked in 1 row, that is not good in any terms of scaling, performance or order.

Yet I cannot see the usecase of your Userlist model.

Once done the above please refer this answer to create your drop down menu, althought the distinct at the end is not needed as creating separate model for Category will avoid the need to duplicate Category names. Then on form submition, you Query for the correct Category and Sub-Category instance and assign it to the ForeignKey field of your form.