求SQL语句：取每一组的ID 最小的记录

[kuevins]

有两个 table：
（1）Customer
CUST_ID | CUST_NAME
-------------------------------------
IBM | IBM Corp.
MS | Microsoft

（2）Product
CUST_ID | PRODUCT_ID | PRODUCT_NAME
-------------------------------------
IBM | I1000 | SERVER
IBM | I1001 | DATABASE
MS | M2222 | OFFICE
MS | M2223 | WINDOWS

现在我想要这两个表关联，每一家公司只取 PRODUCT_ID 最小的那一笔资料，即结果集为：
CUST_ID | CUST_NAME | PRODUCT_ID | PRODUCT_NAME
-----------------------------------------------
IBM | IBM Corp. | I1000 | SERVER
MS | Microsoft | M2222 | OFFICE

我知道可以用子查询来实现：
select ...
from Customer cust,
(select cust_id, min(product_id) from Product group by cust_id) prod
where cust.cust_id = prod.cust_id

但我不能这样做，因为还要串到其他表，要做很复杂的连接。
所以想请教各位大侠，是否有其他更便捷的方式？？

[沝林]

select ...
from
(select Product.*, row_number() over(partition by cust_id order by PRODUCT_ID) rk from Product)
where rk = 1

[UandM]

我觉得
select ...
from Customer cust,
(select cust_id, min(product_id) from Product group by cust_id) prod
where cust.cust_id = prod.cust_id
就很好阿

[kmlinda]

select ...
from Customer cust,product prod
where cust.cust_id=prod.cust_id
and prod.product_id=(select min(product_id) from product where cust_id=prod.cust_id)
其实一样，性能可能还差一点

[辉说慧语]

mark