Multiple Admissions Same Month | Dataford Interview Questions

Providence patient encounter reporting needs to flag patients with repeated inpatient admissions during the same calendar month. Write a PostgreSQL query using the patients and admissions tables.

Requirements

Return each qualifying patient's ID and name, the calendar month, and the number of admissions.
Include a comma-separated, chronologically ordered list of admission IDs for that patient and month.
Return only patient-month groups with at least two admissions, excluding admissions with a missing admission timestamp.
Order results by admission month and patient ID.

Schema

patients

Column	Type	Description
patient_idPK	INTEGER	Unique patient identifier
full_name	VARCHAR(100)	Patient's full name
birth_date	DATE	Patient's date of birth

admissions

Column	Type	Description
admission_idPK	INTEGER	Unique admission identifier
patient_id	INTEGER	Patient associated with the admission
admitted_at	TIMESTAMP	Admission timestamp
discharge_date	DATE	Discharge date when available
admission_type	VARCHAR(30)	Admission classification

Your question is Multiple Admissions Same Month. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem