在 SQL 中按年份并排比较数据 [英] Side-by-side comparison of data by year in SQL

问题描述

我有类似下面的表格:

Year | Product |  Value
2006   A          10
2006   B          20
2006   C          30
2007   A          40
2007   B          50
2007   C          60

我想要一个返回以下比较的查询

I would like a query that would return the following comparison

Product | 2006 Value | 2007 Value
A         10           40
B         20           50
C         30           60

这样做有哪些选择?不用join也可以吗?

What are the options to do so? Can it be done without joins?

我正在使用 DB2，但所有 SQL 类型的答案都会有所帮助.

I'm working with DB2, but answers in all SQL types would be helpful.

推荐答案

select Product, 
    max(case when Year = 2006 then Value end) as [2006 Value], 
    max(case when Year = 2007 then Value end) as [2007 Value] 
from MyTable
group by Product
order by Product

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