Compare Month Admissions | Dataford Interview Questions

Write a SQL query to compare current month admissions with the previous month.

Use the latest non-null admission_date in the data to determine the current month. Count admission records for both months and calculate the absolute and percentage change.

Output

One row containing current_month, current_admissions, previous_month, previous_admissions, change_count, and change_percent
Include zero counts when a month has no admissions
Return change_percent rounded to two decimal places, or NULL when the previous count is zero
Sort by the current month in descending order

Schema

admissions

Column	Type	Description
admission_idPK	INT	Unique admission record identifier
patient_id	VARCHAR(20)	Patient identifier associated with the admission
admission_date	DATE	Date the admission was recorded

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