alt Hacker NewsI generally like ORMs but recognize that they have a lot of problems. The most common problem that I've seen is when an ORM makes it easy to select records in a way that looks efficient but really is not. Strictly speaking, this isn't a failure of the ORM itself -- it's the fault of the developer who is using the ORM and also the developer that didn't catch it in code review. But it's a case where the ORM is making work for everyone and obscuring legibility into the code instead of saving time and providing clarity.
I've written complicated stuff where an ORM isn't appropriate, but if I'm honest, a large fraction of what I've done in my career is just making boring software to automate menial clerical work, and ORMs are good enough for those kinds of projects.
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> Strictly speaking, this isn't a failure of the ORM itself -- it's the fault of the developer
You've got that backwards. If a tool obscures complexity such that a developer using it could be tricked into thinking their efficient-appearing code is actually inefficient, the problem is the tool. A well-designed tool makes inefficiencies explicit. "You're holding it wrong" is not engineering advice.
> ORMs are good enough for those kinds of projects.
It's all good as long as you have properly abstracted it away from your core application. The trouble with some ORM toolkits is that they encourage you to move database logic into the rest of the application and that's when the messes begin. The old school PHP programmers will know well that SQL in raw doesn't automatically mean proper separation of concerns either, but it is more likely to push you in that direction.
Firmly agree. I wish that ORMs provided two interfaces above raw SQL: a syntactically guaranteed-to-hit-indexes set of functions, and a do-anything set (e.g. MyModel.objects.unrestricted.filter(…)) that you could lint for and audit. An unsung benefit of ORMs is that they have code-level awareness of what queries are likely to be fast, since indexes are usually defined in the ORM. I wish they took more advantage of that.