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0 pointsrichardlblair10mo ago0 comments

If your ORM is going to the DB per row you're using it wrong. N+1 queries are a performance killer. They are easy to spot in any modern APM.

Rails makes this easy to avoid. Using `find_each` batches the queries (by 1,000 records at a time by default).

Reading through the comment section on this has been interesting. Either lots of people using half baked ORMs, people who have little experience with an ORM, or both.

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3 comments · 1 top-level

wild_egg10mo ago· 2 in thread

I mean Rails also makes it easy to accidentally nest further queries inside your `find_each` block and end up with the same problem.

Your team can have rules and patterns in place to mitigate it but I'd never say "Rails makes this easy to avoid".

richardlblairOP10mo ago

This is true with any any interaction with the DB, ORM or otherwise. Regardless of the layer of abstraction you choose to operate at you still need to understand the underlying complexity.

What Rails gives you is easy to use (and understand) abstractions that enable you to directly address performance issues.

Easy is highly contextual here, because none of this is trivial.

mathiaspoint10mo ago

I think the real value in frameworks like rails and Django is that it makes it easier to collaborate. When you do it from scratch people inevitably write their own abstractions and then you can't share code so easily.

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