Question

我有一张表Orders (Id, OrderDate, CreatorId)和一张表OrderLines (Id, OrderId, OwnerIdentity, ProductId, Amount)

场景如下：有人打开Order，然后其他用户可以在该订单上下达产品订单。这些用户是OwnerId的{{1}}。

我需要检索用户下订单的前3个最新订单并显示他下达的所有订单，以便让他了解他最近的个人订单。

所以我的最终结果将是

OrderLines

Answer 1

 <my:UserControl1>
                <my:UserControl1.Items>
                    <my:MyItem ButtonText="test" Imagepath="../img.png" />
                    <my:MyItem ButtonText="test2" Imagepath="../img2.png" />
                </my:UserControl1.Items>
            </my:UserControl1>

您可以将日期时间列添加到OrderLines表以查询最新的个人订单，然后通过将“Order by OrderDate desc”部分移动到子选择查询来更新代码。

Answer 2

尝试以下查询：

SELECT OL.OrderId, OL.ProductID, OL.Amount 
FROM OrderLines OL WHERE OL.OrderId IN 
(
  SELECT TOP 3 O.OrderID FROM orders O LEFT JOIN OrderLines OL2 
ON OL2.orderId=O.OrderID 
WHERE OL2.OwnerIdentity =...
ORDER BY O.OrderDate DESC
) AND WHERE OL.OwnerIdentity =...

Answer 3

select * from 
(
select OrderId,  ProductId, Amount 
       row_number() over (partition by OrderID order by Orders.OrderDate) as rn
 from  OrderLines 
 join  Orders 
   on  OrderLines.OrderId = Orders.Id
 where OwnerIdentity = x
) lskdfj
where rn <= 3

Answer 4

;WITH cte AS (
    SELECT ol.OrderId, ol.ProductId, ol.Amount,
           ROW_NUMBER()OVER (PARTITION BY ol.OrderId ORDER BY o.OrderDate DESC) rn 
    FROM OrderLines ol
    JOIN Orders o ON ol.OrderId = o.Id
    WHERE OwnerIdentity = @OwnerId
)
SELECT OrderId, ProductId, Amount
FROM   cte
WHERE  rn <= 3

根据相关表值获取前n个出现次数

4 个答案: