Запрос SQLный

SELECT p.ProductName, c.CategoryName
FROM Products p
LEFT JOIN ProductCategories pc ON p.ProductID = pc.ProductID
LEFT JOIN Categories c ON pc.CategoryID = c.CategoryID
UNION
SELECT p.ProductName, NULL AS CategoryName
FROM Products p
WHERE p.ProductID NOT IN (SELECT ProductID FROM ProductCategories);

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SELECT p.ProductName, c.CategoryName
FROM Products p
LEFT JOIN ProductCategories pc ON p.ProductID = pc.ProductID
LEFT JOIN Categories c ON pc.CategoryID = c.CategoryID