Exercise: Period-over-Period Comparisons
Last Updated: May 12, 2026
1 min read
For this exercise, we will work with below data:
SQL
Exercise 1
Easy
Write a query that returns the total number of streams per month for the entire platform. Show month (truncated to the first day) and stream_count. Order by month.
SQL
Expected Query
Expected Output
Exercise 2
Medium
Write a query that returns total platform revenue per month from the payments table, where revenue is amount - COALESCE(refund_amount, 0) for completed payments. Show month and revenue. Order by month.
SQL