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Comment by FooBarWidget | Hacker News Reader

I find this question to be very weird. I have never seen ORMs as tools for completely abstracting away the database. I have always seen them as convenience APIs for using the database. They exist to make your code shorter, less repetitive, more readable, easier to reason about, and more maintainable; not to make you forget about the database altogether.

I also don't see ORMs as exclusive. It's fine to use ORMs for 95% of your use cases, but drop down to raw SQL for the remaining 5% where it's not a good match. That's still a win for the goals I mentioned above.

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> I have never seen ORMs as tools for completely abstracting away the database.

Some are advertised that way. Entity Framework Code First, Migrations etc.

At our place, our DB dev team is larger than our api team, which in turn collectively dwarfs our front end teams. ORMs in this sort of environment have never really been given a chance, but I feel like it would be easy to justify them in many situations...

> Some are advertised that way

As an example of this, the influential DHH of Basecamp blogged saying just that: https://m.signalvnoise.com/conceptual-compression-means-begi... "Basecamp 3 has about 42,000 lines of code, and not a single fully formed SQL statement as part of application logic!"

Given that these are the people who wrote the Rails ORM, you'd expect that they know how to use the ORM to generate high quality SQL. Which is actually quite doable - in Rails / ActiveRecord you're much better served by knowing what happens for every ORM call, and the default development log prints every generated SQL query as well. Think it now also provides alerts when the queries are slow.

True, but my point was that that blog post supported the point that ORMs are sometimes promoted as a way to avoid needing to know SQL. The intended audience of that blog post was not people who write ORMs, it was to persuade people who are writing applications that they don’t need to learn how to use a database, that they only need to learn how to use an ORM.

Yeah, that's isn't going to work. Would want to use an ORM the way you'd use a bicycle - it won't necessarily let you do something you couldn't before, but it makes it easier. Using an ORM without knowing the SQL it generates is like learning to bicycle without learning to walk. You'll fall down at some point and then you're well and truly screwed.

They also let you compose SQL fragments in ways that would be a lot more difficult or less clear otherwise. In the case of Diesel, they let you typecheck the composition of those fragments. ORM hate is based on misunderstanding of the benefits those who do use them get from them.

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