How can I write a Django query to aggregate the most recently published entry for each author of a collective blog?

Question

Assume the following simplified models:

class Blog(models.Model):
    name = models.CharField()

class Author(models.Model):
    blog = models.ForeignKey('Blog', related_name='authors')

class Entry(models.Model):
   author = models.ForeignKey('Author', related_name='entries')
   published_on = models.DateTimeField(auto_now_add=True)

Given a particular blog's primary key, how would I retrieve a queryset of entries such that the queryset contains only the single most recent entry of each author?

score 1 · Answer 1 · edited May 23 '17 at 12:06

1

Found the answer here:

Django query that get most recent objects from different categories

authors = Author.objects.annotate(latest_entry_published_on=Max('entries__published_on')) 
entries = Entry.objects.filter(published_on__in=[a.latest_entry_published_on for a in authors])

edited May 23 '17 at 12:06

Community

1
1

answered Jan 23 '15 at 02:22

Keith Morris

275
2
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score 0 · Answer 2 · answered Jan 23 '15 at 02:20

0

I'd try something like:

Entry.objects.order_by('-published_on').values_list('author_id').distinct()

answered Jan 23 '15 at 02:20

dan-klasson

13,734
14
63
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How can I write a Django query to aggregate the most recently published entry for each author of a collective blog?

2 Answers2