Django, connect one field with multiple models

Question

I guess it is a "normal" problem. I want to connect model C with different Models A,B,..

Model A "buildings"
 - time_built
 - description
 - adress
 - architects[]=Model C
 - places

Model B "photos":
 - time_taken
 - title
 - architects[]=Model C
 - places

Model C "architects"
- title
- time_born
- website
- items[]=Model A+Model B

So items should be connected m:n to Model A or B for querying like "find architects by buildings in California". Model A and B can have multiple architects.

Is it possible to realize something like this in Django? I thought to use a Intermediate Model, but as I understood it does not help me too.

score 0 · Answer 1 · answered Feb 18 '20 at 15:53

0

Yes, Django has Many-to-many relationships.

In Buildings, put

    architects = models.ManyToManyField(Architect)

In Photos, put

    architects = models.ManyToManyField(Architect)

This will handle the relationship and by creation the migration file and running it, the DB tables will be created automatically (they should be 5).

answered Feb 18 '20 at 15:53

Horatiu Jeflea

7,256
6
38
67

I know this. But then I cannot query for architects who built buildings in Germany? – rokdd Feb 18 '20 at 16:05
`Buildings.objects.filter(country_name='Germany').architects` will do that trick – Horatiu Jeflea Feb 18 '20 at 16:08
Okay good to know, but then it does not search in the photos.places as well? – rokdd Feb 18 '20 at 16:35
you can do the same thing in photos also. Pretty much anything you can do in plain SQL – Horatiu Jeflea Feb 18 '20 at 16:44
I meant both at same time? But I guess I thought it from the wrong side of relation. – rokdd Feb 18 '20 at 16:47

score 0 · Answer 2 · answered Feb 18 '20 at 17:06

Ok seems that there are two solutions:

changing the layout of Models like Horatiu mentioned
or what I found by random now and solved my problem what I was looking for: GenericForeignKeys - good example to explain and another question at stackoverflow

Django, connect one field with multiple models

2 Answers2