#35941: Add composite GenericForeignKey support
-------------------------------------+-------------------------------------
     Reporter:  Csirmaz Bendegúz     |                     Type:  New
                                     |  feature
       Status:  new                  |                Component:  Database
                                     |  layer (models, ORM)
      Version:  dev                  |                 Severity:  Normal
     Keywords:                       |             Triage Stage:
                                     |  Unreviewed
    Has patch:  0                    |      Needs documentation:  0
  Needs tests:  0                    |  Patch needs improvement:  0
Easy pickings:  0                    |                    UI/UX:  0
-------------------------------------+-------------------------------------
 This is a follow up to #373 (''CompositePrimaryKey'').

 **Proposal:**

 My proposal is to implement ''GenericForeignKey'' support with **JSON**.

 1. `object_id` is a `CharField` (or `TextField`)
 2. ''CompositePrimaryKey'' is stored as a ''JSON array'' in `object_id`
 3. JOINs can be achieved with JSON functions (varies per db backend)

 If anyone is interested, I have a proof of concept available on my
 [https://github.com/csirmazbendeguz/django/pull/9 GitHub] (it's an out of
 sync draft right now, I'll submit a proper PR once composite primary keys
 are merged).

 **Risks:**

 1. What if someone is using a JSON array as the primary key (but it's not
 a composite primary key)?
 ''Before deserializing the JSON array, we need to check if the content
 type has a composite primary key or not.''
 2. What if the db backend doesn't support JSON functions?
 ''All supported databases support JSON functions.''

 **Notes:**

 Django admin's `LogEntry` has its own implementation of "generic foreign
 keys".
 The approach we take with `GenericForeignKey` should also apply to
 `LogEntry`.
-- 
Ticket URL: <https://code.djangoproject.com/ticket/35941>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion visit 
https://groups.google.com/d/msgid/django-updates/01070193679aeffc-d26d0228-b8c1-4bbb-83de-824b5bfd56ad-000000%40eu-central-1.amazonses.com.

Reply via email to