mysql - 如何在mysql中选择每个客户的最后订单日期

Question

table_customers(customer_id, customer_name)
table_orders(customer_id, order_id, order_datetime)

我想获取每个客户的最后订单日期。如果客户没有下任何订单，请为她返回 00-00-0000。

这是我的查询。

select C.customer_id , date(O.order_datetime) 
from table_customers C 
INNER JOIN table_orders O ON C.customer_id = O.customer_id 
group by O.customer_id order by O.order_datetime desc limit 1;

它仅返回最后一位客户的最后订单日期。

如何获取所有客户的最后订单日期？

Answer 1

您好，请检查下面的 sql..

select coalesce(max(o.order_datetime), '0000-00-00 00:00:00') as last_order_date, c.customer_id 
from table_orders as o
right join table_customers as c on o.customer_id = c.customer_id
group by c.customer_id
order by c.customer_id;

这可能对你有帮助。

示例结果如下。