Monthly Revenue

EasySQLSQL

Solve this the way you would in the interview: out loud, on a timer, with an AI interviewer asking follow-ups while you code. You get a scored report at the end.

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Problem

Table orders: id INTEGER primary key placed_on TEXT a date as 'YYYY-MM-DD' status TEXT 'completed', 'refunded' or 'pending' total REAL Return revenue per month, counting completed orders only. Columns, in this order: month as 'YYYY-MM', number of completed orders, their summed total. Order by month, ascending. A month with no completed orders does not appear.

Examples

Input: orders id | placed_on | status | total 1 | 2026-01-05 | completed | 20.0 2 | 2026-01-20 | refunded | 50.0 3 | 2026-02-01 | completed | 10.0
Output: 2026-01 | 1 | 20.0 2026-02 | 1 | 10.0

Constraints

  • Dates are text, so the first seven characters are the month.

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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