是否可以向 GROUP BY 添加标识列,以便每个重复项都有一个标识号?
我的原始数据如下所示:
1 AAA [timestamp]
2 AAA [timestamp]
3 BBB [timestamp]
4 CCC [timestamp]
5 CCC [timestamp]
6 CCC [timestamp]
7 DDD [timestamp]
8 DDD [timestamp]
9 EEE [timestamp]
....
我想将其转换为:
1 AAA 1
2 AAA 2
4 CCC 1
5 CCC 2
6 CCC 3
7 DDD 1
8 DDD 2
...
解决方案是:
CREATE PROCEDURE [dbo].[RankIt]
AS
BEGIN
SET NOCOUNT ON;
SELECT *, RANK() OVER(PARTITION BY col2 ORDER BY timestamp DESC) AS ranking
FROM MYTABLE;
END
最佳答案
您可以尝试使用 ROW_NUMBER如果您使用的是 Sql Server 2005
DECLARE @Table TABLE(
ID INT,
Val VARCHAR(10)
)
INSERT INTO @Table SELECT 1,'AAA'
INSERT INTO @Table SELECT 2,'AAA'
INSERT INTO @Table SELECT 3,'BBB'
INSERT INTO @Table SELECT 4,'CCC'
INSERT INTO @Table SELECT 5,'CCC'
INSERT INTO @Table SELECT 6,'CCC'
INSERT INTO @Table SELECT 7,'DDD'
INSERT INTO @Table SELECT 8,'DDD'
INSERT INTO @Table SELECT 9,'EEE'
SELECT *,
ROW_NUMBER() OVER(PARTITION BY VAL ORDER BY Val)
FROM @Table
关于sql - 是否可以使用 SQL 将身份添加到 GROUP BY?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/2066178/