Question

我知道这对你们大多数人来说很简单！

我有一个像这样的发票表：

+-----------+------------+------+-------+
| InvoiceID |    Date    | Item | Price |
+-----------+------------+------+-------+
|         1 | 15/04/2014 | A    |    12 |
|         2 | 20/04/2014 | A    |    20 |
|         3 | 20/04/2014 | A    |    27 |
|         4 | 20/04/2014 | B    |    29 |
|         5 | 28/04/2014 | C    |    16 |
|         6 | 28/04/2014 | B    |    11 |
+-----------+------------+------+-------+

我想根据每件商品的最后发票ID检索价格，所以：

+------+-----------+
| Item | LastPrice |
+------+-----------+
| A    |    27     |
| B    |    11     |
| C    |    16     |
+------+-----------+

最有效的方法是什么？我使用的是SQL Server 2008

非常感谢任何收到的帮助。

Answer 1

with cte as (
   select *, row_number() over (partition by Item order by date desc) as r
   from dbo.YourTable
)
select * from cte where r = 1

Answer 2

这可以做你的工作：

SELECT Item,
       Price AS 'LastPrice'
FROM   MyTable
WHERE  InvoiceId IN (SELECT Max(InvoiceId)
                 FROM   MyTable
                 GROUP  BY Item)

在SQL中检索上一个发票价格

2 个答案: