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Do Long Trips Get Cancelled?

mediumSQLGroupByAggregation

A product manager at UrbanHop has a theory: long trips get cancelled more often, because a driver looking at a forty-minute run to the edge of the city would rather wait for something shorter. If that is happening, it is a matching problem worth money. The first step is cheap — compare the typical distance of the bookings that completed against the ones that did not.

Every booking carries a distance, whether it happened or not, because the distance is estimated when the ride is booked. That is what makes the comparison possible at all.

rides — one row per booking. rider_id points at a row in riders and driver_id at a row in drivers. distance_km is the trip length in kilometres and fare the price in dollars; both are recorded when the booking is made, so a booking that never happened still carries them. status is either completed or cancelled. ride_date is the day the ride was booked for.

id rider_id driver_id distance_km fare ride_date status
1 1 1 5.2 12.5 2023-06-01 completed
2 1 4 3.0 8.0 2023-06-03 completed
3 2 2 10.0 22.0 2023-06-02 completed
4 3 1 2.1 6.5 2023-06-05 cancelled
5 3 4 4.4 11.0 2023-06-06 completed
6 4 3 7.8 18.0 2023-06-04 completed
7 5 2 1.5 5.0 2023-06-07 cancelled
8 2 2 12.3 26.5 2023-06-10 completed
9 1 1 6.6 15.0 2023-06-12 completed
10 4 3 3.3 9.0 2023-06-15 completed
11 5 2 8.8 19.5 2023-06-18 completed
12 3 4 2.9 7.5 2023-06-20 cancelled

The table already exists in the database — there is nothing to create or load.

Task: Write a query that returns one row per status, with status and the mean distance of the bookings carrying that status, rounded to two decimal places, as avg_km. Statuses in alphabetical order.

Example output

Shape only — the two status labels are the real ones, the figures are invented:

status avg_km
cancelled 5.4
completed 9.13

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