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copied!<p>Adding custom queries to managers is the Django convention. From the Django docs on <a href="https://docs.djangoproject.com/en/dev/topics/db/managers/#custom-managers" rel="noreferrer">custom managers</a>:</p> <blockquote> <p>Adding extra Manager methods is the preferred way to add "table-level" functionality to your models.</p> </blockquote> <p>If it's your own private app, the convention word doesn't matter so much - indeed my company's internal codebase has a few classmethods that perhaps belong in a custom manager. </p> <p>However, if you're writing an app that you're going to share with other Django users, then they'll expect to see <code>findBy</code> on a custom manager.</p> <p>I don't think the inheritance issues you mention are too bad. If you read the <a href="https://docs.djangoproject.com/en/dev/topics/db/managers/#custom-managers-and-model-inheritance" rel="noreferrer">custom managers and model inheritance docs</a>, I don't think you'll get caught out. The verbosity of writing <code>.objects</code> is bearable, just as it is when we do queries using <code>XYZ.objects.get()</code> and <code>XYZ.objects.all()</code></p> <p>Here's a few advantages of using manager methods in my opinion:</p> <ol> <li><p>Consistency of API. Your method <code>findBy</code> belongs with <code>get</code>, <code>filter</code>, <code>aggregate</code> and the rest. Want to know what lookups you can do on the <code>XYZ.objects</code> manager? It's simple when you can introspect with <code>dir(XYZ.objects)</code>. </p></li> <li><p>Static methods "clutter" the instance namespace. <code>XYZ.findBy()</code> is fine but if you define a static method, you can also do <code>xyz.findBy()</code>. Running the <code>findBy</code> lookup on a particular instance doesn't really make sense.</p></li> <li><p>DRYness. Sometimes you can use the same manager on more than one model.</p></li> </ol> <p>Having said all that, it's up to you. I'm not aware of a killer reason why you should not use a static method. You're an adult, it's your code, and if you don't want to write <code>findBy</code> as a manager method, the sky isn't going to fall in ;)</p> <p>For further reading, I recommend the blog post <a href="http://www.b-list.org/weblog/2008/feb/25/managers/" rel="noreferrer">Managers versus class methods</a> by James Bennett, the Django release manager.</p>

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