Data Analyst · SQL · Junior · Theory

What's the difference between the window functions ROW_NUMBER, RANK, and DENSE_RANK?

~4 min by voice

How to approach it

The interviewer wants to see whether you understand what window functions are and how they differ from GROUP BY, whether you can explain precisely how the three functions behave with equal values, and whether you can apply them to a typical task like "top N per group".

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sql window functions

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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