如何从select语句的结果中为变量赋值？

Question

SELECT TOP 1 [FirstName], [LastName]
FROM [table]

DECLARE @firstName VARCHAR(25)

运行上面的查询后，我想将从查询中带回的[FirstName]分配给@firstName。

我该怎么做？

Answer 1

DECLARE @firstName VARCHAR(25) 

SELECT TOP 1 @firstName = [FirstName] FROM [table] 

Answer 2

像这样：

DECLARE @firstName VARCHAR(25), @LastName VARCHAR(25)

SELECT TOP 1 @firstName = [FirstName], @LastName = [LastName]
FROM [table]

Answer 3

使用SET从查询中分配值：

DECLARE @firstName VARCHAR(25)

SET @firstName = (SELECT TOP 1 [FirstName] FROM [table])