title: Annotate only returns specified grouping values - Django
body: <p>I'm trying to sum column values of some rows with the a specific column value (currency_id) using annotate.</p>
  <p>My rows look like this:</p>
  <pre><code>id  |  amount  |  currency_id  |  info1  |  info2
  
  1   |  14      |  1            |  xxx    |  xxx
  2   |  25      |  1            |  xxx    |  xxx
  3   |  92      |  2            |  yyy    |  yyy
  </code></pre>
  <p>And I want to get this:</p>
  <pre><code>id  |  amount  |  currency_id  |  info1  |  info2
  
  1   |  39      |  1            |  xxx    |  xxx
  3   |  92      |  2            |  xxx    |  xxx
  </code></pre>
  <p>Here is my code:</p>
  <pre><code>items = Item.objects.values('currency_id').annotate(
                  Sum('amount'),
              )
  </code></pre>
  <p>Which works but I only get the column currency_id and the amount sum in the result:</p>
  <pre><code>&lt;QuerySet [{'currency_id': 1, 'amount__sum': 39}, {'currency_id': 2, 'amount__sum':92]
  </code></pre>
  <p>This is because I use values() to specify the column to group.
  How can I get all other columns values?</p>