medium10 pts · first answer countssqldata-analysis

Finding customers with no orders

You need a list of customers who have never placed an order. Which query is correct?

-- customers(id, name)
-- orders(id, customer_id, amount)

A.SELECT c.id, c.name FROM customers c LEFT JOIN orders o ON o.customer_id = c.id WHERE o.customer_id IS NULLB.SELECT c.id, c.name FROM customers c INNER JOIN orders o ON o.customer_id = c.id WHERE o.amount = 0C.SELECT c.id, c.name FROM customers c INNER JOIN orders o ON o.customer_id = c.idD.SELECT c.id, c.name FROM customers c WHERE c.id IS NULL

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