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    <pre><code>threads = Thread.objects.filter( Q(message_set__from_user=u) | Q(message_set__to_user=u) ).order_by('id') messages = Message.objects.filter( Q(thread__in=threads) &amp; Q(Q(thread__from_user=u) | Q(thread_to_user=u)) ).order_by('thread__id', '-when').select_related('from_user', 'to_user') from itertools import groupby t_index = 0 for thread_messages in groupby(messages, lambda x: x.thread_id): if threads[t_index].id is thread_messages[0].thread_id: threads[t_index].messages = thread_messages t_index += 1 </code></pre> <p>That might look a bit complex or scary but it <em>should</em> do what you are after. Essentially it queries all your threads first so we can find out what threads we've messaged about. Then it finds all the related messages to those threads.</p> <p>Both of the queries are ordered by the same field so that in the lower part of the code we can iterate through the list only once, instead of needing a nested for loop to find each thread with the correct id. They are also both filtered by the same query (regarding thread objects at least) to ensure we are getting back only the relevant results to this query.</p> <p>Lastly, the messages that we received back are grouped together and attached to each thread; they will show up in descending order for each thread.</p> <p>Right at the end, you may also want to re-sort your threads to show the latest ones first, easy to do assuming a 'when' field on the Thread model:</p> <p>threads = sorted(threads, key=lambda x: x.when, reverse=True)</p> <p>By using the aforementioned method, you will have to do 2 queries every time, regardless, first the threads, then the messages. But it will never go above this (watch out for joins on a select_related though or recursive queries on related objects).</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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