How many completed trips never got a rating?
The Zoomi product team suspects riders skip the rating screen too often, which makes driver scores noisy. A trip that was rated has a number from 1 to 5 in rating; an unrated trip has NULL. Cancelled requests are never rated, so they would distort the picture and must be ignored.
Task: looking only at trips with status 'Completed', return a single row with completed_trips, unrated_trips (rating is NULL), unrated_pct (percentage of completed trips that are unrated, ROUND(x, 2)) and avg_rating (average of the ratings that exist, ROUND(x, 2)).
The data you can query
Each table is shown with its column types and the first rows, so you can see exactly what the data looks like.
| id INTEGER | name TEXT | country TEXT |
|---|---|---|
| 1 | Dubai | UAE |
| 2 | Lahore | Pakistan |
| 3 | Singapore | Singapore |
| 4 | Nairobi | Kenya |
| id INTEGER | name TEXT | city_id INTEGER | joined_on TEXT | vehicle_type TEXT |
|---|---|---|---|---|
| 1 | Rashid Al Mansoori | 1 | 2025-09-18 | Economy |
| 2 | Tariq Mehmood | 2 | 2026-02-05 | Economy |
| 3 | Wei Jie Tan | 3 | 2025-09-08 | Comfort |
| 4 | Samuel Kiptoo | 4 | 2025-11-12 | Economy |
| 5 | Hassan Qureshi | 1 | 2025-12-20 | Economy |
| 6 | Priya Raman | 2 | 2025-06-24 | Economy |
Showing the first 6 of 8 rows.
| id INTEGER | name TEXT | home_city_id INTEGER | signup_date TEXT |
|---|---|---|---|
| 1 | Ayesha Khan | 1 | 2026-03-09 |
| 2 | Bilal Okafor | 2 | 2026-02-26 |
| 3 | Chen Silva | 3 | 2026-03-12 |
| 4 | Diego Tanaka | 4 | 2026-03-30 |
| 5 | Elena Weber | 1 | 2026-06-04 |
| 6 | Farid Nguyen | 2 | 2026-05-23 |
Showing the first 6 of 32 rows.
| id INTEGER | rider_id INTEGER | driver_id INTEGER | city_id INTEGER | requested_at TEXT | status TEXT | distance_km REAL | fare_usd REAL | surge REAL | rating INTEGER |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 5 | 1 | 2026-04-06 08:23:01 | Completed | 4 | 6.9 | 1 | 5 |
| 2 | 4 | 8 | 4 | 2026-04-06 10:42:25 | Completed | 13.1 | 9.44 | 1.25 | 5 |
| 3 | 3 | 3 | 3 | 2026-04-06 13:24:49 | Completed | 3.5 | 5.53 | 1 | 5 |
| 4 | 2 | 2 | 2 | 2026-04-06 17:17:07 | Completed | 15.8 | 9.5 | 1.5 | 4 |
| 5 | 1 | 1 | 1 | 2026-04-06 18:25:11 | Completed | 11.8 | 19.35 | 1.25 | 4 |
| 6 | 4 | 8 | 4 | 2026-04-06 21:01:43 | Completed | 16.6 | 9.3 | 1 | 4 |
Showing the first 6 of 548 rows.
Your query runs on SQLite. Write a single SELECT; use LIMIT instead of TOP.
Need a hint?
AVG skips NULL values on its own, COUNT(*) does not.
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