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Driver Utilization

mediumSQLJoinsGroupBy

Utilisation review at UrbanHop asks a blunt question about each driver: how much work did they actually deliver? Bookings that were cancelled are not work — the driver may have been inconvenienced, but nothing was delivered and nothing was earned — so only completed trips count towards the figure.

The bookings identify a driver by number, and the review is read by a city manager who knows her drivers by name. A driver with no completed trips at all has no utilisation to review and does not appear on the sheet.

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

drivers — one row per driver on the platform. rating is their running star rating out of 5, and city is the city they drive in.

id name city rating
1 Sam Rios Austin 4.9
2 Priya Desai Denver 4.6
3 Oscar Lund Seattle 4.8
4 Nina Cole Austin 4.2

Both tables already exist in the database — there is nothing to create or load.

Task: Write a query that returns one row per driver with at least one completed trip, with their name and how many completed trips they delivered as trips. Busiest first; drivers on the same number of trips are separated alphabetically by name.

Example output

Shape only — these drivers and counts are invented:

name trips
Dana Fox 7
Milo Reyes 5
Rosa Vega 5
Tariq Bell 2

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