取得每个标识符组第一个记录SQL

Question

Code  Description  Whatever 
--------------------------------- 
1  stuff   blah 
1  something  meh 
2  yah    bong 
2  never   hammer time 

如何获取结果从这组与各Code只出现一次？ （我不太在乎那个代码的记录）。

所以我想....

1  stuff   blah 
2  yah    bong 

Answer 1

SELECT * 
FROM (
SELECT * , row_number() over(partition by code order by Description) as id 
from yourTable 
) temp 
WHERE id = 1 

我觉得这是SQL服务器只

Answer 2

首先，您需要选择哪些决定作为“第一个结果制”最重要的列。在我的例子中，我选择了Description：

SELECT * FROM YourTable first 
WHERE 
    (SELECT COUNT(*) FROM YourTable previous 
    WHERE previous.Code=first.Code AND previous.Description < first.Description) = 0