[Answered ]-How can I retrieve brands based on specific category in django?

by

1👍

You can .filter(…) [Django-doc] with:

Brand.objects.filter(Products__category=my_category).distinct()

or for a category name:

Brand.objects.filter(
    Products__category__category_name=my_category_name
).distinct()

the .distinct() call [Django-doc]
prevents returning the same Brand multiple times.

Note: normally the name of the fields in a Django model are written in snake_case, not PascalCase.
Since the value for the related_name=… parameter [Django-doc]
specifies the name of a field that will be defined on the target model, the value of the related_name=… parameter should be written in snake_case as well, so it should be: products instead of Products.

Note: Your Product model acts as a junction table for a many-to-many relation between Category and Brand. You can span a
ManyToManyField [Django-doc]
on the Category model with:

class Category(models.Model):
    # …
    brands = models.ManyToManyField(
        Brand,
        through='Product'
    )
👤willeM_ Van Onsem

0👍

Based on your models it should be something like:

brand_names = Product.objects.filter(category__category_name="some_name").values_list("brand_name__brand_name", flat=True)

or if by brand_name you mean Brand model instances then

brand_names = Product.objects.filter(category__category_name="some_name").brand_name.all()

(BTW I would consider renaming fields in your models. In Product model rename brand_name to just brand and inside Brand rename field brand_name to just name. The same for Category. It will be much less confusing)

👤Bartosz Stasiak

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