Python · Mid-level · Theory

The order list page in the Django admin takes ten seconds to load, and the logs show hundreds of SQL queries per page load. What's going on, and how do you fix it?

~4 min by voice

How to approach it

The interviewer wants to see whether you recognize the N+1 problem in the Django ORM from its symptoms, understand the mechanism of lazy loading of relations, and can fix it systematically and keep it from coming back: select_related/prefetch_related, diagnostic tools, tests on the number of queries.

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Topics

django orm

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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