Data Analyst · SQL · Mid-level · Coding

There's a sales table with the columns product_id, category, amount, and sold_at. Write a SQL query that, for each category, returns the three products with the highest revenue over the last thirty days, with the revenue total and the rank within the category.

~15 min by voice

How to approach it

They're checking whether you understand SQL's order of execution (WHERE → GROUP BY → windows → outer filter), whether you can aggregate first and rank afterwards, and whether you deal deliberately with equal revenue and an index-friendly date filter.

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Topics

top n per group 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 · ~15 min