擅长:python、mysql、java
<p>这可以通过使用<a href="https://docs.djangoproject.com/en/3.1/topics/db/queries/#lookups-that-span-relationships" rel="nofollow noreferrer">lookups through relationships</a>,根据所需字段<code>uploaded_datetime</code>排序,然后从每个查询中检索<a href="https://docs.djangoproject.com/en/3.1/ref/models/querysets/#last" rel="nofollow noreferrer">last values</a>来实现。如下例所示:</p>
<pre><code>qs = Document.objects.filter(user=user)
latest_uploaded_credit_card = qs.filter(doc_type__document_class='C').order_by('uploaded_datetime').last()
latest_uploaded_debit_card = qs.filter(doc_type__document_class='D').order_by('uploaded_datetime').last()
</code></pre>