Year-over-Year Growth SQL | Dataford Interview Questions

Write a SQL statement to calculate year-over-year growth metrics from raw event logs.

Use the provided event log and event type data. Include only event types and years with a matching prior calendar year.

Output

One row per event type and year.
Columns: event_type_name, event_year, event_count, prior_year_count, yoy_change, and yoy_growth_pct.
Sort by event_type_name, then event_year ascending.

event_types

Column	Type	Description
event_type_idPK	INT	Unique event type identifier
event_type_name	VARCHAR(100)	Readable event type name

event_logs

Column	Type	Description
event_idPK	INT	Unique raw event identifier
event_type_id	INT	Referenced event type identifier
occurred_at	TIMESTAMP	Timestamp when the event occurred

Your question is Year-over-Year Growth SQL. Start with the requirements and the two tables in the Question tab.

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