mysql - 在sql查询中查找重复列并保存为排名

Question

我有第二列的表按降序排列

a 30  
a 28
a 18
a 10
b 40
b 34
c  32
c  22

我想要这样的结果

a 30  1
a 28  2
a 18  3
a 10  4
b 40  1
b 34  2
c  32  1
c  22  2

谢谢..！

Answer 1

尝试这个

SELECT t1.*, COUNT(*) AS rank
FROM Table1 t1
INNER JOIN 
Table1 t2 on t1.col1 = t2.col1
AND t1.col2 <= t2.col2
GROUP BY t1.col1, t1.col2
ORDER BY t1.col1, t1.col2 DESC

• SQLFiddle 演示

Answer 2

这是使用变量的方法

SET @level:=1;
SET @group='';
SELECT
    column1,
    column2,
    Sort
FROM(
    SELECT 
        column1,
        column2,
        @level :=(IF(@group = column1,@level+1 ,1)) AS `Sort`, 
        @group := column1
    FROM t
ORDER BY column1 ASC, column2 DESC
) AS l;

SQL 小提琴演示

输出

| COLUMN1 | COLUMN2 | SORT |
----------------------------
|       a |      30 |    1 |
|       a |      28 |    2 |
|       a |      18 |    3 |
|       a |      10 |    4 |
|       b |      40 |    1 |
|       b |      34 |    2 |
|       c |      32 |    1 |
|       c |      22 |    2 |

Answer 3

我目前没有安装 mysql 但应该有等效的，甚至这可能有效：

SELECT 
 a, b, row_number() OVER (PARTITION BY a ORDER BY a ASC, b DESC) 
FROM test GROUP BY a, b ORDER BY a ASC, b DESC;

适用于 postgresql 9.2