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SQL Top 3 Hospitals by Region
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SQL Top 3 Hospitals by Region

MediumSQL · PostgreSQL

Problem

Write SQL to find the top 3 hospitals by readmission rate in each region.

Use the hospitals and patient_discharges tables. Calculate readmission rate as readmitted discharges divided by eligible discharges with a known readmission value.

Output

  1. One row per hospital selected for its region
  2. Columns: region, hospital_id, hospital_name, eligible_discharges, readmitted_discharges, readmission_rate, and regional_rank
  3. Include up to three hospitals per region, ordered by region, rank, and hospital ID for ties

Schema

hospitals
ColumnTypeDescription
hospital_idPKINTEGERUnique hospital identifier
hospital_nameVARCHAR(100)Hospital name
regionVARCHAR(50)Geographic region containing the hospital
patient_discharges
ColumnTypeDescription
discharge_idPKINTEGERUnique discharge record identifier
hospital_idINTEGERHospital associated with the discharge
discharge_dateDATEDate of discharge
readmitted_30dBOOLEANWhether the patient was readmitted within 30 days
Tableshospitalspatient_discharges
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