I'm currently working on Correlated Subqueries II. The exercise seems trivially simple, since the example given is so close to the solution, but I'm not having any luck getting it correct. I get a table without errors that looks like it fulfills all the requirements of the solution, but I get the error message
"Find the origin, flight id, and sequence number."
SELECT origin, id, (SELECT COUNT(*) FROM flights f WHERE f.id < flights.id AND f.carrier=flights.carrier)+1 AS flight_sequence_number FROM flights;
Am I missing something silly, or is this a bug?