题解 | #确定最佳顾客的另一种方式（二）#

-- groupby 和having是一对，不能用where
-- HAVING子句将过滤条件应用于每组分行，而WHERE子句将过滤条件应用于每个单独的行
SELECT c.cust_name,tb.total_price
FROM
    Customers c
    INNER JOIN Orders o
    ON c.cust_id = o.cust_id
    INNER JOIN(
        SELECT order_num,SUM(item_price*quantity) AS total_price
        FROM OrderItems
        GROUP BY order_num
        HAVING total_price >= 1000
    ) tb
    ON tb.order_num = o.order_num

ORDER BY tb.total_price ASC;