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Active Patient Cohort SQL
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Active Patient Cohort SQL

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the active patient cohort that visited a primary care physician more than three times in the last calendar year.

Assume the last calendar year is 2025. Treat patients with active_status = TRUE as active, and count only visits to physicians whose specialty is Primary Care.

Output

  1. One row per qualifying patient.
  2. Columns: patient_id, patient_name, and visit_count.
  3. Include only patients with more than three qualifying visits in 2025.
  4. Order by visit_count descending, then patient_id ascending.

Schema

patients
ColumnTypeDescription
patient_idPKINTUnique patient identifier
patient_nameVARCHAR(100)Patient's display name
active_statusBOOLEANWhether the patient is currently active
visits
ColumnTypeDescription
visit_idPKINTUnique visit identifier
patient_idINTPatient associated with the visit
physician_idINTPhysician associated with the visit
visit_dateDATEDate of the visit
physicians
ColumnTypeDescription
physician_idPKINTUnique physician identifier
physician_nameVARCHAR(100)Physician's display name
specialtyVARCHAR(100)Physician specialty
Tablespatientsvisitsphysicians
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