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PODjango - optimization question
 

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    <p>If you have some models:</p> <pre><code>class Teacher(models.Model): name = models.CharField(max_length=50) class Student(models.Model): age = models.PositiveIntegerField() teacher = models.ForeignKey(Teacher, related_name='students') </code></pre> <p>and you use it like this:</p> <pre><code>&gt;&gt;&gt; student = Student.objects.get(pk=1) &gt;&gt;&gt; student.teacher.name # This hits the database 'Some Teacher' &gt;&gt;&gt; student.teacher.name # This doesn't (``teacher`` is cached on the object) 'Some Teacher' </code></pre> <p>That's awesome. Django caches the related object so that you can use it again without having to abuse your database.</p> <p><strong>But</strong>, if you use it like this:</p> <pre><code>&gt;&gt;&gt; teacher = Teacher.objects.get(pk=1) &gt;&gt;&gt; for student in teacher.students.all(): # This hits the database ... print(student.age) ... 8 6 &gt;&gt;&gt; for student in teacher.students.all(): # This does too (obviously) ... print(student.age) ... 8 6 </code></pre> <p>There's no caching or efficient access to related objects this direction.</p> <p><strong>My question is thus:</strong> Is there a built-in (or non-problematic way) to backward access related objects in an efficient way (a cached way), like you can in the <code>student.teacher</code> example above?</p> <p>The reason I want this is because I have a model with multiple methods that need access to the same related objects over and over, so a page that should have 12 queries ends up with about 30.</p>
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