SQL拆分重复并重命名

Question

我有一张包含员工ID和UserNames的表。某些员工ID是重复的，但UserName是不同的。我需要中断重复项并使用新的员工ID将它们添加回列表。

例如：

EMPID|UserName
1    | Josh
2    | John
2    | Kate
2    | Jorge
3    | Taylor
3    | Morgan
4    | Nathan

我需要将其切换为：

1|Josh
2|John
3|Taylor
4|Nathan
5|Kate
6|Jorge
7|Morgan

我知道要查找重复项的SQL。但要做这种举动，我很遗憾。

谢谢！

Answer 1

测试数据

DECLARE @TABLE TABLE (EMPID INT, UserName VARCHAR(10))
INSERT INTO @TABLE VALUES
(1 ,'Josh') ,(2 ,'John')  ,(2 ,'Kate'),
(2 ,'Jorge'),(3 ,'Taylor'),(3 ,'Morgan'),4 ,'Nathan')

更新查询

;WITH CTE AS 
(
 SELECT * , ROW_NUMBER() OVER (ORDER BY EMPID,UserName) + (SELECT MAX(EMPID) FROM @TABLE) New_ID
 FROM @TABLE t
 WHERE NOT EXISTS (SELECT EMPID , MAX(UserName) AS UserName1
                  FROM @TABLE
                  WHERE  EMPID = t.EMPID
                  GROUP BY EMPID
                  HAVING   MAX(UserName) = t.UserName)
)
UPDATE CTE 
 SET EMPID = New_ID

RESULT

SELECT * FROM @Table

╔═══════╦══════════╗
║ EMPID ║ UserName ║
╠═══════╬══════════╣
║     1 ║ Josh     ║
║     2 ║ Kate     ║
║     3 ║ Taylor   ║
║     4 ║ Nathan   ║
║     5 ║ John     ║
║     6 ║ Jorge    ║
║     7 ║ Morgan   ║
╚═══════╩══════════╝