运行 #10

Sol

汇总完成订单中各商品的净销售额，并使用 ROW_NUMBER 选出每个品类排名前三的商品；同额时 product_id 较小者优先。

WITH product_revenue AS (
  SELECT
    p.category,
    p.product_id,
    p.product_name,
    SUM(oi.quantity * oi.unit_price - oi.discount_amount) AS net_revenue
  FROM fact_order_items AS oi
  JOIN fact_orders AS o
    ON oi.order_id = o.order_id
  JOIN dim_products AS p
    ON oi.product_id = p.product_id
  WHERE
    o.status = 'completed'
  GROUP BY
    p.category,
    p.product_id,
    p.product_name
), ranked_products AS (
  SELECT
    category,
    product_id,
    product_name,
    net_revenue,
    ROW_NUMBER() OVER (PARTITION BY category ORDER BY net_revenue DESC, product_id ASC) AS rank_no
  FROM product_revenue
)
SELECT
  category,
  product_id,
  product_name,
  net_revenue,
  rank_no
FROM ranked_products
WHERE
  rank_no <= 3
ORDER BY
  category ASC,
  rank_no ASC