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    <p>@lazerscience is absolutely correct. You should tweak your models, since you are setting up a de facto many-to-many relationship; doing so will allow you to leverage more features of the admin interface &amp; so forth.</p> <p>Additionally, regardless, there is no need to go to <code>raw()</code>, since this can be done entirely via normal usage of the Django ORM.</p> <p>Something like:</p> <pre><code>class LadderPlayer(models.Model): player = models.ForeignKey(User, unique=True) position = models.IntegerField(unique=True) challenges = models.ManyToManyField("self", symmetrical=False, through='Match') class Match(models.Model): date = models.DateTimeField() challenger = models.ForeignKey(LadderPlayer) challengee = models.ForeignKey(LadderPlayer) </code></pre> <p>should be all you need to change in the models. You then should be able to do a query like</p> <pre><code>player_of_interest = LadderPlayer.objects.filter(pk=some_id) matches_of_interest = \ Match.objects.filter(Q(challenger__pk=some_id)|Q(challengee__pk=some_id)) </code></pre> <p>to get all the information of interest about the player in question. Note that you'll need to have <code>from django.db.models import Q</code> to use that.</p> <p>If you want <em>exactly</em> the same info you're presenting with your example query, I believe it'd be easiest to split the queries into separate ones for getting the challenger &amp; challengee lists -- for example, something like:</p> <pre><code>challengers = LadderPlayer.objects.filter(challenges__challengee__pk=poi_id) challenged_by = LadderPlayer.objects.filter(challenges__challenger__pk=poi_id) </code></pre> <p>will get the two relevant query sets for the player of interest (w/ a primary key of <code>poi_id</code>).</p> <p>If there's some particular reason you don't want the de facto many-to-many relationship to become a de jure one, you can change those to something along the lines of</p> <pre><code>challenger = LadderPlayer.objects.filter(match__challengee__pk=poi_id) challenged_by = LadderPlayer.objects.filter(match__challenger_pk=poi_id) </code></pre> <p>So the suggestion for the model change is merely to help leverage existing tools, and to make explicit a relationship which you are currently having occur implicitly.</p> <p>Based on how you want use it, you might want to do something like</p> <pre><code>pl_tuple = () for p in LadderPlayer.objects.all(): challengers = LadderPlayer.objects.filter(challenges__challengee__pk=p.id) challenged_by = LadderPlayer.objects.filter(challenges__challenger__pk=p.id) pl_tuple += (p.id, p.position, challengers, challenged_by) context_dict['ladder_players'] = pl_tuple </code></pre> <p>in your view to prepare the data for your template.</p> <p>Regardless, you should probably be doing your query through the Django ORM instead of using <code>raw()</code> in this case.</p>
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    1. POLeft join query in Django with multiple joins against same table
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    1. USdesfido
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    1. COWell the only reason where making a raw query would make sense in this example if you want to this with hitting the database only ONCE. django will not return objects in a many-to-many relation or reverse-foreign-key relation with ONLY ONE query!
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    2. COTrue, but I think that's likely a premature optimization -- and since the questioner was asking how to do it via the ORM, I rather suspect that the choice to use `raw()` was made due to lack of experience w/ the ORM, rather than due to performance considerations.
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    3. COThanks for the detailed reply, I will have to study it. On initial glance, it doesn't seem right to me to have a challenges field in the LadderPlayer model. "challenge" is not an attribute of a player. Also, a player can only be in one single challenge at a time, as either a challenger or challengee. So a challenge must have two players, and a player can be involved in 0 or 1 challenge...doesn't strike me as a traditional many-to-many situation.
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