Backend · Senior · Theory

Tell me about a time you denormalized a data model for the sake of performance. What price did you have to pay for it?

~4 min by voice

How to approach it

The interviewer checks whether you can sacrifice normalization deliberately: see a real problem backed by numbers, try cheap alternatives first, choose a mechanism for keeping copies in sync, and honestly name the price: more expensive writes, more complex code, the risk of drift and how you catch it.

Have you seen this question in a real interview?

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Topics

data modeling sql

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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