姓名     年龄   金额

张小姐    20    121
李小姐    25    254
陈小姐    30    365

USE tempdb

create table mytest
(
    [name] nvarchar(10),
    age int,
    price numeric(12)
)

insert into mytest([name],age,price) values ('张小姐','20','121')
insert into mytest([name],age,price) values ('李小姐','25','254')
insert into mytest([name],age,price) values ('陈小姐','30','365')


select * from mytest where age <=25

SELECT sum(price) as valprice from mytest where age <=25
/*
375
*/