选择Top into Different Variables

Question

可能不可能,但我想我会问;

我想得到Top并将每个保存到一个不同的变量.我知道有3个选择并且可以从第1,第2,第3开始,Top 3但是我希望它可能在一个声明中？

IE

Declare @Var1 as int,
Declare @Var2 as int,
Declare @Var3 as int
select Top 3 [SAVE 3 RETURNED RECORDS INTO VARIABLES] from Table

Answer 1

假设您想要演示目的TOP 3 schema_id FROM sys.objects ORDER BY object_id.

Declare @Var1 as int;
Declare @Var2 as int;
Declare @Var3 as int;


WITH T AS
(
SELECT *,
       ROW_NUMBER() OVER (ORDER BY object_id) RN
FROM sys.objects
)
SELECT @Var1 = MAX(CASE WHEN RN = 1 THEN schema_id END),
       @Var2 = MAX(CASE WHEN RN = 2 THEN schema_id END),
       @Var3 = MAX(CASE WHEN RN = 3 THEN schema_id END)
FROM T 
WHERE RN <= 3;

SELECT @Var1, @Var2, @Var3

它用于ROW_NUMBER对行进行编号,然后将它们转换为单行结果,用于分配变量.