hard20 pts · first answer countssqljoins

LEFT JOIN that acts like INNER JOIN

You want all customers with their 2026 orders, including customers with none. This query drops customers with no orders: SELECT c.id, o.id FROM customers c LEFT JOIN orders o ON o.customer_id = c.id WHERE o.year = 2026. Why?

A.LEFT JOIN never keeps unmatched rowsB.The year column must be indexedC.Customers without orders have o.year = 0D.For unmatched customers o.year is NULL, so the WHERE condition removes them; move it into the ON clause

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