sql - Simplest way to process multiple hardcoded values in SQL?

Question

How would I do this in SQL Server? (I know it won't run as written but it illustrates the question better than I can explain)

SELECT SQRT(number) WHERE number IN (4,9,16,25)

It would return multiple rows of course

Answer 1

您可以使用表值构造函数

select sqrt(number) 
from (
    values (4),(9),(16),(25)
) as T(number)

或使用联合所有

select sqrt(number)
from (
    select 4 union all
    select 9 union all
    select 16 union all
    select 25
) as T(number)

sql fiddle demo

Answer 2

您可以创建一个派生表：

SELECT SQRT(number)
FROM (
    SELECT 4 AS number
    UNION ALL SELECT 9
    UNION ALL SELECT 16
    UNION ALL SELECT 25
) A