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SQL for First-Trip Duration
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SQL for First-Trip Duration

MediumSQL · PostgreSQL

Problem

Write a query to find the average trip duration for guests who booked their first trip in the last 30 days on Turo.

Use the guests and trips tables. Treat a guest's earliest booking timestamp as their first trip, and calculate the average duration of those qualifying first trips. Use the database's current date for the 30-day window.

Output

  1. Return one row with average_trip_duration_hours.
  2. Include only first bookings from the inclusive 30-day window through the current date.
  3. Report duration in hours, rounded to two decimal places.

Schema

guests
ColumnTypeDescription
guest_idPKINTUnique identifier for a Turo guest
guest_nameVARCHAR(100)Guest display name
account_statusVARCHAR(20)Current guest account status
trips
ColumnTypeDescription
trip_idPKINTUnique identifier for a trip
guest_idINTGuest who booked the trip
booked_atTIMESTAMPTimestamp when the trip was booked
trip_startTIMESTAMPTrip start timestamp
trip_endTIMESTAMPTrip end timestamp
Tablesgueststrips
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