Data Analyst · SQL · Junior · Coding

There's an orders table with the columns order_id, created_at, and amount. Write a SQL query that, for each day, returns the date, the revenue for that day, and the cumulative revenue since the start of the period, in ascending order of date.

~15 min by voice

How to approach it

They're checking whether you understand the difference between aggregation (GROUP BY) and window functions and can combine them correctly: first collapse the orders down to days, then compute the running total on top of the daily sums.

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Answers0

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Topics

running totals 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