Backend · Mid-level · Theory

The orders list page has started taking several seconds to load, and in the logs you see hundreds of near-identical SQL queries per HTTP request. What's going on, and how would you fix it?

~4 min by voice

How to approach it

This checks whether you recognize the N+1 problem from its symptoms, understand how it arises in an ORM, and can fix it systematically: confirm it by measuring, choose between a JOIN and batch loading, and protect against regressions.

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Topics

sql orm query performance

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min