如何查詢那些有具有相同價值的一列列中是最高的列值的行

Question

我UserScores表的數據是這樣的：

Id userId Score 
1  1  10 
2  2  5 
3  1  5 

我想有一個查詢或SQL塊，可以給我下面的輸出

Id userId Score 
3  1  5 
2  2  5 

也就是說，我想挑選是由屬於最高的「ID」列值「用戶ID」唯一行。

Answer 1

另一種解決方案，將在SQL Server上運行2000（同INNER JOIN以上，但稍快）是：

SELECT id, userId, Score 
    FROM UserScores 
WHERE id in (SELECT MAX(id) 
       FROM UserScores 
       GROUP BY userId 
      ) 
ORDER BY userId 

Answer 2

用途：

WITH summary AS (
    SELECT t.id, 
       t.userid, 
       t.score, 
       ROW_NUMBER() OVER (PARTITION BY t.userid ORDER BY t.id DESC, t.score DESC) AS rank 
     FROM USERSCORES sc) 
SELECT s.id, 
      s.userid, 
      s.score 
    FROM summary s 
WHERE s.rank = 1 

Answer 3

如何

SELECT MAX(Id), userId, Score 
FROM table 
GROUP BY UserId 

Answer 4

SELECT U2.id, U2.userId, U2.score 
FROM UserScores U2 
INNER JOIN (
    SELECT U1.userId, MAX(U1.Id) MaxId 
    FROM UserScores U1 
    GROUP BY U1.userId 
) U3 
ON U2.id = U3.MaxId and U2.userId = U3.userId 
ORDER BY U2.userId