Home/ Questions/Q 548971
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-13T11:08:09+00:00

I have three tables: users, courses and documents. I would like to upload documents

  • 0

I have three tables: “users”, “courses” and “documents”. I would like to upload documents to users as well as to courses, so I would need two belongsTo-relations for the Document model. Some belong to one model, some to the other.

Is there a simple solution to construct these relations?

How could I set up the “add”-actions?

I know I could set up two join tables and use HABTM, but that doesn’t feel right. A document belongs only to one other item. Besides, I want to be able to extend the relations to more models if neccessary.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    What you’re looking for is called polymorphism. Basically, you’re not associating a model with a fixed other model through a single other_model_id field, but you keep track of two fields: other_model_class and other_model_foreign_key. That way you can associate a Document with class: User, id: 42 in one case and class: Course, id: 42 in another. There’s a Behavior in the Bakery, which should be a good place to start.

    • 0