如何两列组合在SQL

Question

我在SQL两个列

year month 
2016 4 
2014 5 

我想现在要做的就是这两列组合在一起，并得到时期

输出

year month result 
2016 4  201604 
2014 5  201405 

有没有办法做到这一点？

Answer 1

如果列的数据类型是整数，做

select year * 100 + month from tablename 

Answer 2

首先，您需要将它们CAST改为VARCHAR以允许连接。然后使用RIGHT为month到垫0值：

WITH Tbl AS(
    SELECT 2016 AS [year], 4 AS [month] UNION ALL 
    SELECT 2014, 5 
) 
SELECT *, 
    CAST([year] AS VARCHAR(4)) + RIGHT('0' + CAST([month] AS VARCHAR(2)), 2) 
FROM Tbl 

Answer 3

假设两列是数值类型：

SELECT year, 
     month, 
     CAST(year as char(4)) + RIGHT('00' + CAST(month as varchar(2)), 2) as result 
FROM YourTable