Question

我想在网格视图上显示特定客户的最后一个订单，我所做的是显示客户的所有订单，但我需要最后一个订单

这是我的SQL代码

     SELECT orders.order_id, orders.order_date, 
    orders.payment_type, orders.cardnumber, packages.Package_name,
 orders.package_id, packages.package_price 
    FROM orders INNER JOIN packages ON orders.package_id = packages.Package_ID 
    WHERE (orders.username = @username )

@username从cookie中获取其值，现在我如何才能选择最后一个订单仅用于cookie值“Tony”？

Answer 1

为了概括（并修复一下）Mitch的答案，你需要使用带有TOP（@N）和ORDER BY ... DESC的SELECT子句。请注意，我使用TOP（@N），而不是TOP N，这意味着您可以将它作为参数传递给存储过程并返回，例如，不是1但是N最后一个订单：

CREATE STORED PROCEDURE ...
    @N int
...
SELECT TOP(@N) ...
ORDER BY ... DESC

Answer 2

SELECT top 1 
   orders.order_id, 
   orders.order_date,  
   orders.payment_type, 
   orders.cardnumber, 
   packages.Package_name, 
   orders.package_id, 
   packages.package_price  
FROM orders 
INNER JOIN packages ON orders.package_id = packages.Package_ID  
WHERE (orders.username = @username ) 
ORDER BY orders.order_date DESC

实际上假设orders.order_id是一个标识列：

SELECT top 1 
   orders.order_id, 
   orders.order_date,  
   orders.payment_type, 
   orders.cardnumber, 
   packages.Package_name, 
   orders.package_id, 
   packages.package_price  
FROM orders 
INNER JOIN packages ON orders.package_id = packages.Package_ID  
WHERE (orders.username = @username ) 
ORDER BY orders.order_id DESC

特定客户的订单的最后记录 - SQL

2 个答案: