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    <p>You could use <code>annotate</code>, <code>extra</code> or <code>raw</code>. Here's how you'd use <code>annotatate</code>:</p> <pre><code>books = [a.book_set.latest('pub_date') for a in Author.objects .annotate(latest=Max('book__pub_date')) .order_by('-latest')[:5]] </code></pre> <p>Assuming the authors don't have multiple books with the same <code>pub_date</code> you could use <code>extra</code> like this:</p> <pre><code>sql = '''SELECT MAX(app_book.pub_date) FROM app_book WHERE app_book.author_id=app_author.id''' latest = Author.objects.extra( select={'latest': sql}, order_by=['-latest'])[:5].values_list('latest') books = Book.objects.filter(pub_date__in=[x[0] for x in latest]).order_by('-pub_date') </code></pre> <p>If you use <code>raw</code> you could grab all the books with a single query:</p> <pre><code>sql = '''SELECT * FROM app_book WHERE app_book.pub_date IN (SELECT MAX(app_book.pub_date) FROM app_book GROUP BY app_book.author_id) ORDER BY app_book.pub_date DESC''' books = list(Book.objects.raw(sql)[:5]) </code></pre> <p>I'm assuming models like the following:</p> <pre><code>class Author(models.Model): name = models.CharField(max_length=50) class Book(models.Model): title = models.CharField(max_length=50) author = models.ForeignKey(Author) pub_date = models.DateTimeField() class Meta: get_latest_by = 'pub_date' </code></pre> <p>For fun I thought I'd benchmark the three approaches (using a db filled with about 100k dummy books):</p> <pre><code>&gt;&gt;&gt; %time annotate() (0.274) SELECT "app_author"."id", "app_author"."name", MAX("app_book"."pub_date") AS "latest" FROM "app_author" LEFT OUTER JOIN "app_book" ON ("app_author"."id" = "app_book"."author_id") GROUP BY "app_author"."id", "app_author"."name", "app_author"."id", "app_author"."name" ORDER BY "latest" DESC LIMIT 5; args=() (0.035) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."author_id" = 10 ORDER BY "app_book"."pub_date" DESC LIMIT 1; args=(10,) (0.036) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."author_id" = 9 ORDER BY "app_book"."pub_date" DESC LIMIT 1; args=(9,) (0.036) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."author_id" = 8 ORDER BY "app_book"."pub_date" DESC LIMIT 1; args=(8,) (0.036) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."author_id" = 7 ORDER BY "app_book"."pub_date" DESC LIMIT 1; args=(7,) (0.040) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."author_id" = 6 ORDER BY "app_book"."pub_date" DESC LIMIT 1; args=(6,) CPU times: user 0.32 s, sys: 0.15 s, total: 0.47 s Wall time: 0.47 s &lt;&lt;&lt; [&lt;Book: Susan&gt;, &lt;Book: Yasmin&gt;, &lt;Book: Carl&gt;, &lt;Book: Benny&gt;, &lt;Book: George&gt;] &gt;&gt;&gt; %time extra() (0.445) SELECT (SELECT MAX(app_book.pub_date) FROM app_book WHERE app_book.author_id=app_author.id) AS "latest" FROM "app_author" ORDER BY "latest" DESC LIMIT 5; args=() (0.045) SELECT "app_book"."id", "app_book"."title", "app_book"."author_id", "app_book"."pub_date" FROM "app_book" WHERE "app_book"."pub_date" IN (2038-11-25 11:33:30.425836, 2038-11-24 11:33:30.424598, 2038-11-23 11:33:30.423435, 2038-11-22 11:33:30.422227, 2038-11-21 11:33:30.421045) ORDER BY "app_book"."pub_date" DESC; args=(u'2038-11-25 11:33:30.425836', u'2038-11-24 11:33:30.424598', u'2038-11-23 11:33:30.423435', u'2038-11-22 11:33:30.422227', u'2038-11-21 11:33:30.421045') CPU times: user 0.32 s, sys: 0.18 s, total: 0.50 s Wall time: 0.50 s &lt;&lt;&lt; [&lt;Book: Susan&gt;, &lt;Book: Yasmin&gt;, &lt;Book: Carl&gt;, &lt;Book: Benny&gt;, &lt;Book: George&gt;] &gt;&gt;&gt; %time raw() (0.279) SELECT * FROM app_book WHERE app_book.pub_date IN (SELECT MAX(app_book.pub_date) FROM app_book GROUP BY app_book.author_id) ORDER BY app_book.pub_date DESC; args=() CPU times: user 0.19 s, sys: 0.09 s, total: 0.28 s Wall time: 0.28 s &lt;&lt;&lt; [&lt;Book: Susan&gt;, &lt;Book: Yasmin&gt;, &lt;Book: Carl&gt;, &lt;Book: Benny&gt;, &lt;Book: George&gt;] </code></pre>
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    1. POHow to retrieve the first X objects with unique attribute value
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    1. COTotal number of SQL queries in your code is 6, isn't it? The desired result can be achieved with just 2 queries.
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    2. CO@dragoon How would you do it? The other way that came to mind was to use `raw` which would result in a single query.
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    3. COSee the link in my question, I agree with this solution, though somebody claimed that the solution does not work :/
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