Question

我想创建一个返回客户最新销售订单的查询。

我有一个Customer和一个Orders表，它们在ID上加入，我已经进行了以下查询以返回所有值。任何人都可以帮我修改它只返回每个ID的最新值吗？ Orders.created_at的格式如下yyyy-MM-dd HH：mm：ss

SELECT Customers.ID, Customers.Name, Customers."Sales Responsible US", Customers."Sales     Responsible", Customers."Website", ISNULL(Orders.row_invoiced, '-1'), Orders.status, Orders.created_at
FROM "Customers"
LEFT JOIN Orders
On Customers.ID=Orders.customer_id

Answer 1

尝试在创建的订单上放置MAX。按客户ID分组。（错字）

PS：我在移动设备上。没有代码片段格式。

Answer 2

试试这个::

   SELECT Customers.ID, 
Customers.Name, 
Customers."Sales Responsible US", 
Customers."Sales     Responsible", 
Customers."Website", 
IFNULL(Orders.row_invoiced, '-1'), 
Orders.status, MAX(Orders.created_at)
    FROM "Customers"
    LEFT JOIN Orders On Customers.ID=Orders.customer_id

    group by Orders.customer_id

Answer 3

我会将您已经拥有的所有内容加入到每个客户（max(created_at)）获得最新（group by customer_id）订单日期的子查询中。

SELECT Customers.ID, 
    Customers.Name, 
    Customers."Sales Responsible US", 
    Customers."Sales     Responsible", 
    Customers."Website", 
    ISNULL(Orders.row_invoiced, '-1'), 
    Orders.status, 
    Orders.created_at
FROM "Customers"
LEFT JOIN Orders On Customers.ID=Orders.customer_id
left join (
    select customer_id, max(created_at) as created_at
    from Orders 
    group by customer_id
) as t on Orders.customer_id = t.customer_id and Orders.created_at = t.created_at

Answer 4

嗨希望这能满足您的要求

SELECT Customers.ID, Customers.Name, Customers."Sales Responsible US", Customers."Sales     Responsible", Customers."Website", ISNULL(Orders.row_invoiced, '-1'), Orders.status, MAX(Orders.created_at)
FROM "Customers"
LEFT JOIN Orders
On Customers.ID=Orders.customer_id 
GROUP BY Orders.customer_id

MySQL返回最近一行的唯一ID

4 个答案: