Python · Senior · Theory

Tell me about the N+1 query problem in the Django ORM. How do you find it, and which ORM tools do you use to fix it?

~4 min by voice

How to approach it

This checks whether you understand how QuerySet laziness produces extra queries and can make a deliberate choice between select_related, prefetch_related, Prefetch, annotate and narrowing the fields. It also matters how you catch N+1 systematically, not from complaints about a slow page.

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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