题解 | 检索每个顾客的名称和所有的订单号(二)
检索每个顾客的名称和所有的订单号(二)
https://www.nowcoder.com/practice/4e73c4e770b941c9abc60814601ed498
# 列出所有的顾客,根据表的位置,使用左还是右联结
#右联结
SELECT
C.cust_name,
O.order_num
FROM
Orders O RIGHT JOIN Customers C ON O.cust_id = C.cust_id
ORDER BY
C.cust_name
#左联结
SELECT
C.cust_name,
O.order_num
FROM
Customers C LEFT JOIN Orders O ON O.cust_id = C.cust_id
ORDER BY
C.cust_name
