SQL Join Types | Dataford Interview Questions

Can you explain the different types of joins in SQL and when you would use each?

Use the provided customers and orders tables to demonstrate the behavior of a join that preserves unmatched rows from both tables. Explain how INNER, LEFT, RIGHT, FULL OUTER, CROSS, and self joins differ.

Output

One row per matched or unmatched customer and order relationship
Columns: customer_id, customer_name, order_id, order_customer_id, and join_status
Include unmatched rows from both tables and order by the coalesced customer identifier, then order_id

Schema

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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Problem