Rewriting this database access query to circumvent 'DISTINCT ON' error, in Django

Question

I have two very simple models:

class Link(models.Model):
    description = models.TextField(validators=[MaxLengthValidator(500)])
    submitter = models.ForeignK         


        

Answer 1

You could just take care of the distinct in memory.

replies_by_link = {}
replies = Publicreply.objects.filter(answer_to_id__in=link_ids).order_by('answer_to', 'submitted_on')

for reply in replies:
    if reply.answer_to_id not in replies_by_link:
        replies_by_link[reply.answer_to_id] = reply

and then you can access all the replies via replies_by_link.values().