Inner Join vs Outer Join | Dataford Interview Questions

How do you explain the difference between an inner join and an outer join in a database context?

Write a PostgreSQL query that demonstrates the distinction by returning matched and unmatched records from the provided customer and order data.

Output

One row for each matched relationship and each unmatched record.
Columns: customer_id, customer_name, order_customer_id, order_id, and match_status.
Sort by the related customer identifier, placing unmatched records with null identifiers last, then by order_id.

customers

Column	Type	Description
customer_idPK	INT	Unique customer identifier
customer_name	VARCHAR(100)	Customer display name

orders

Column	Type	Description
order_idPK	INT	Unique order identifier
customer_id	INT	Customer associated with the order
order_status	VARCHAR(30)	Current order status

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