Choose Correct SQL Joins | Dataford Interview Questions

Explain the difference between inner, left, and full joins and when you would use each in a product analysis context.

Use the provided tables to demonstrate the three join behaviors with a single PostgreSQL query. Include matched records, users without events, and events without users.

Output

One row per join result, with join_type, user_id, country, event_id, and event_name.
Include results for INNER, LEFT, and FULL joins, labeled by join_type.
Order by join type in the sequence INNER, LEFT, FULL, then by user_id and event_id.

Schema

remitly_users

Column	Type	Description
user_idPK	INT	Unique Remitly user identifier
country	VARCHAR(2)	User's two-letter country code

product_events

Column	Type	Description
event_idPK	INT	Unique product event identifier
user_id	INT	User associated with the event, when available
event_name	VARCHAR(50)	Name of the product event

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