Data Analyst · SQL · Junior · Theory

Imagine a query against a large table is running very slowly. Where would you start investigating?

~4 min by voice

How to approach it

They're checking whether you have a systematic approach to diagnosing a slow query: start with the execution plan rather than guesses, understand the role of indexes and their cost, and spot the typical traps in the query itself.

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Topics

sql query optimization

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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