24.sql

机械工业出版社《SQL Server应用开发实例教程》源代码

select gpcd as 光盘产地,gpyy as 光盘语言 ,
avg(gpdj) as 平均价格,
sum(qnt)  as 光盘总数
from gpb
WHERE gph<10  
group by gpyy ,gpcd
having sum(qnt)<10