where e.order_no=f.order_no) g group by cust_id having count

来源：学生作业帮编辑：大师作文网作业帮分类：英语作业时间：2024/11/06 13:34:38

where e.order_no=f.order_no) g group by cust_id having count(distinct prod_id)>=3) h) 为什么要加h?
select a.cust_id,cust_name,b.prod_id,prod_name,d.qty,d.qty*d.unit_price
from customer a,product b,sales c,sale_item d
where a.cust_id=c.cust_id and d.prod_id=b.prod_id and
c.order_no=d.order_no and a.cust_id in (
select cust_id
from (select cust_id,count(distinct prod_id) prod_id
from (select cust_id,prod_id
from sales e,sale_item f
where e.order_no=f.order_no) g
group by cust_id
having count(distinct prod_id)>=3) h)

简化后其实是这样的
from (
from () g
) h
h与g都叫做表别名,因为from子句后面()没有明确的表名,
需要添加表别名来让系统识别,h和g分别代表内部的select输出

where e.order_no=f.order_no) g group by cust_id having count group by zuozhebianhao having count(*)>=3 group by o.ownerid having count(o.id)>=2 group by 零件号 having count（项目号）=3 oracle中 HAVING count(1) group by sex having count(*)>4; 怎么使用 WHERE S.Sno=SC.Sno AND Cname!="数据结构"GROUP BY Sname HAVING AV GROUP BY，WHERE，HAVING之间的区别和用法 select.where student_id>3 GROUP BY math_mark having AVG(math group by a having a='1' 和 where a='1' group by a有什么区别呢?在某些情况 mysql中的select语句where条件group by ,having ,order by,limit的顺序及用法在SQL语句中,select,where,group by,having,order by,这几个关键字程序执行顺序是怎 oracle group by和having用法