Convert three modelsto one single query django query - django-models

Question

This are my model with some of the fields:
class Advertisers(models.Model):
account_manager_id = models.ForeignKey(AccountManagers, on_delete=models.CASCADE,null=True, db_column='account_manager_id',related_name="advertisers")
class AdvertiserUsers(models.Model):
user_id = models.OneToOneField('Users', on_delete=models.CASCADE,null=True,db_column='user_id', related_name='advertiser_users')
advertiser_id = models.ForeignKey('Advertisers', on_delete=models.CASCADE,null=True,db_column='advertiser_id', related_name='advertiser_users')
class Users(models.Model):
email = models.CharField(unique=True, max_length=100)
I want Id's, user ids and email of all advertisers.
Id's of all user:-
advertiser_ids = advertisers.objects.all() # can get id from here
find user_ids of advertiser_ids:
user_ids = AdvertiserUsers.objects.filter(advertiser_id__in=advertiser_ids) # can get user_id from here
find id and email using this query:
user_ids = Users.objects.filter(id__in=user_ids) # can get email from here
How to make it shorter like directly querying from Advertisers i will be able to get Users models email.
Thankyou in advance

Answer 1

You can filter with:
Users.objects.filter(advertiser_users__advertiser_id__isnull=False).distinct()
The .distinct() [Django-doc] will prevent returning the same Users multiple times.
You can annotate the User objects with the Advertisers primary key, etc:
from django.db.models import F
Users.objects.filter(advertiser_users__advertiser_id__isnull=False).annotate(
account_manager_id=F('advertiser_users__advertiser_id__account_manager_id'),
advertiser_id=F('advertiser_users__advertiser_id')
)
The Users objects that arise from this have a .email attribute (and the other attributes that belong to a Users object), together with a .account_manager_id and an .advertiser_id. That being said, this is probably not a good idea: the way you have modeled this right now, is that a Users object can relate to multiple Advertisers objects, so it makes not much sense to add these together.
You can for each user access the related Advertisers with:
myusers = Users.objects.filter(
advertiser_users__advertiser_id__isnull=False
).prefetch_related(
'advertiser_users',
'advertiser_users__advertiser_id'
).distinct()
for user in myusers:
print(f'{user.email}')
for advuser in user.advertiser_users.all():
print(f' {advuser.advertiser_user.pk}')
Note: normally a Django model is given a singular name, so User instead of Users.
Note: Normally one does not add a suffix _id to a ForeignKey field, since Django
will automatically add a "twin" field with an _id suffix. Therefore it should
be account_manager_id, instead of account_manager.

Answer 2

Advertisers.objects.all().values_list('id','account_manager_id','advertiser_users__user_id',advertiser_users__user_id__email)