Backend · Junior · Theory

You're told that one database query has started running very slowly. How would you look for the cause?

~4 min by voice

How to approach it

They're checking whether you have a systematic approach to diagnosing database performance: find the problem query, read the execution plan, understand why the index isn't working, and confirm the fix with a measurement — rather than guessing "I'll add an index or get a bigger server."

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Topics

query performance indexes

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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