Accessing the parent object pointing to children objects in Many-to-Many Relationship Django

Question

I have the following models below:

class Account(models.Model):
    courses = models.ManyToManyField(Course)

class Course(models.Model):
    name = models.CharField(blank=True, null=True)

Can I access the account object pointing to a course from a course? Say for example:

course = Course.objects.get(id=1)

account_parent = course.parent_pointing_to_me

With a many-to-many fields, by definition you can have *many* "parents pointing to me". If you just want one, you should use a ForeignKey instead. — Daniel Roseman, May 14 '18 at 10:54
Yes @reza_khalafi . You may refer to the answer here in this SO question: https://stackoverflow.com/a/2642645/4826123 Basically, you need to access it via the `related_name` — Jude Maranga, Aug 22 '22 at 07:40

score 3 · Accepted Answer · answered May 14 '18 at 09:40

3

You can get list of accout related to the class using account_set attribute (see docs):

account_parents = course.account_set.all()

Since account_set is related manager, you can use any other queryset method, for example if you need first account in the list:

account_parent = course.account_set.first()

answered May 14 '18 at 09:40

neverwalkaloner

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what if I want to get only those courses that don't have any account ID ? – Zain Khan Dec 20 '21 at 22:40
@ZainKhan you can try to filter it like this `Course.objects.filter(account__isnull=True)`. Check this doc for more details: https://docs.djangoproject.com/en/4.0/topics/db/queries/#lookups-that-span-relationships – neverwalkaloner Jan 27 '22 at 05:12
what is SET? this is not work – reza_khalafi Aug 21 '22 at 06:48

Accessing the parent object pointing to children objects in Many-to-Many Relationship Django

1 Answers1