with t1 as ( select o.product_id, month(o.order_date) as mon, p.unit_price, sum(o.quantity*p.unit_price) as mon_sales, sum(o.quantity) as mon_qty from orders o left join products p on o.product_id = p.product_id where year(order_date) = 2023 group by 1,2,3 ), t2 as ( select o.product_id, case when c...