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Top 10 Readmission Patients
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Top 10 Readmission Patients

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the top 10 patients by readmission rates at Massachusetts General Hospital.

Use the patients and admissions tables. Treat is_readmission_30d = TRUE as a readmission and include only patients with at least one admission.

Output

  1. One row per patient, with patient_id, patient_name, total_admissions, readmissions_30d, and readmission_rate_pct.
  2. Include at most 10 patients, ordered by rate descending, then readmission count descending, total admissions descending, and patient ID ascending for deterministic ties.

Schema

patients
ColumnTypeDescription
patient_idPKINTUnique patient identifier
patient_nameVARCHAR(100)Patient full name
admissions
ColumnTypeDescription
admission_idPKINTUnique admission identifier
patient_idINTPatient associated with the admission
admission_dateDATEDate the admission began
is_readmission_30dBOOLEANWhether the admission was a documented readmission within 30 days
Tablespatientsadmissions
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