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Comment by ajgrover | Hacker News Reader

Many/most ORMs (the ones that follow the ActiveRecord pattern) do this as well though. I prefer to avoid mixing concerns and use datamapper-based ORMs myself, but what GP wrote is fundamentally not that different than what a lot of ORMs do.

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I'd dispute "most", as it does not match my experience across a number of languages. Yes, active record sorta does it but, as best I recall, those methods are all implemented generically as mixins, so not actually a part of the data object. This seems to be advocating for data specific queries to be added to each class.

Rails and Django are both AR, and are still probably the two most widely used backend frameworks, for better or for worse.

I don’t disagree with the overall point you’re making, I’m just pointing out that it’s very common

Ummm... No. See my previous comment - at least in Rails, the queries aren't part of the data object themselves, but are instead mixins or default handlers (don't recall which offhand), so it's really just syntactic sugar that makes it appear as though they are methods on the data class.

Even if they did the same thing you're suggesting, by that logic, we should all use PHP because WordPress does, and it's probably more popular than those two combined.

Take a look at something like Spring or Entity Framework to see other takes on ORM patterns.

And again, you're trying to argue against ORMs, while citing that your suggested alternative is supported by the way ORMs do it.

I’m not the person that suggested handwriting object methods. As I’ve said, I agree with the point you’re making, I’m not arguing with you, or for any specific ORM design.

I don’t see what the nuance is you’re getting at with the mixin vs object method argument though. They both have the same issues around testability and violation of SRP.

Ahh, apologies misread the tree. In terms of the nuance around a mixin vs object - a mixin can be defined and tested in its own separate library independent of your data model, so it's at least cleaner in terms of separation of concerns.

That’s fair. My issue with the mixin approach is that then your app code can hit the database from anywhere you have access to the model object, which makes testing your own code in isolation much more difficult

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