Asp.net 如何将多个列值连接到单个列中?
我有以下几位朋友Asp.net 如何将多个列值连接到单个列中?,asp.net,sql-server,visual-studio-2012,concatenation,Asp.net,Sql Server,Visual Studio 2012,Concatenation,我有以下几位朋友 id | first_name | last_name | gender | age | mobile 1 | bobby | roe | male | 21 | 541-5780 如何将多个列(first_name和last_name)值连接到一个列中以获得以下结果 full_name bobby roe 我已经编写了以下查询,但它不起作用 declare @full_name varchar(max) select @full_name
id | first_name | last_name | gender | age | mobile
1 | bobby | roe | male | 21 | 541-5780
如何将多个列(first_name和last_name)值连接到一个列中以获得以下结果
full_name
bobby roe
我已经编写了以下查询,但它不起作用
declare @full_name varchar(max)
select @full_name = COALESCE(@full_name + ', ', '') + first_name, last_name
from friend
select @full_name
实现这一点的方法不止一种:
SELECT CONCAT(first_name, ' ' ,last_name) AS full_name;
对于早期版本(CONCAT不是内置函数):
SELECT first_name + ISNULL(' ' + last_name, '') as Full_Name from [YourTable]
这也会给你同样的结果
SELECT COALESCE(first_name, '') + COALESCE(last_name, '') as FullName FROM [YourTable]
“它不工作”可能与您的意思重复?有错误吗?意外输出?根本没有输出?