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SQL practice question · Medium · Date & Time · UnitedHealth

service_contacts has one row per support call (patient_id, call_time). For each patient, compute the time between their first and their most recent call in whole hours, rounded down (a patient with a single call gets 0). Output columns: patient_id, elapsed_hours. Order by patient_id ascending.

Table: service_contacts

Schema of service_contacts
ColumnType
patient_idINTEGER
call_timeTIMESTAMP
Sample rows of service_contacts
patient_idcall_time
1012026-01-01 09:00:00
1012026-01-03 10:00:00
1022026-02-01 12:00:00
1022026-02-05 12:00:00
Expected output on the sample data
patient_idelapsed_hours
10149
10296

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