DB2将多行选择为一行

Question

我有以下内容：

UserID | Number
1 | 100
1 | 200
1 | 300
2 | 20
2 | 21
2 | 22
3 | 333
......
.....
1000| 23
.......

and I want to get the following result:
UserID | Average
1 | 200
2 | 21
3 | 300
......
......
1000 | 200
......

这些价​​值只是为了了解我在说什么！ 提前谢谢！

Answer 1

使用AVG聚合：

SELECT UserId, AVG(Number)
FROM YourTable
GROUP By UserId

SQL Fiddle Demo

Answer 2

SELECT UserID, AVG(Number) AS Average
FROM YourTable
GROUP BY UserID