Product_Sales_Analysis_III.sql

WITH CTE AS (
    SELECT product_id, MIN(year) AS minyear FROM Sales 
    GROUP BY product_id 
)

SELECT s.product_id, s.year AS first_year, s.quantity, s.price 
FROM Sales s
INNER JOIN CTE ON cte.product_id = s.product_id  AND s.year = cte.minyear;