sql-server-2008 - 如何检索char列的最大出现值

Question

我在获得列的最大出现次数时遇到问题

 matnum   uom  amount
-------------------------------------
1234    EA   10
1234    CS   10
1234    EA    20
1235    CS   10
1235    CS    20

---

我的输出选择应该是

 matnum   uom  SUM(amount)
-------------------------------------
1234   EA (because EA occured Twice)    40
1235   CS                               30

---

请提供一个选择查询以获得所需的结果

Answer 1

我在这里假设一些关于你想要什么的事情，但是：

SELECT A.matnum, B.uom, C.s AS [SUM(amount)]
FROM yourtable A
INNER JOIN (
    SELECT matnum, uom, 
        ROW_NUMBER() OVER (PARTITION BY matnum ORDER BY COUNT(*) DESC) AS rnm
    FROM yourtable
    GROUP BY matnum, uom
) B ON A.matnum = B.matnum AND B.rnm = 1
INNER JOIN (
    SELECT matnum, SUM(amount) AS s 
    FROM yourtable 
    GROUP BY matnum
) C ON A.matnum = C.matnum
GROUP BY A.matnum, B.uom, C.s

SQL小提琴

Answer 2

select matnum, 
       uom, 
       SUM(amount) as sum_amount
from your_table
group by matnum, uom

Answer 3

select max(matnum) as matnum,max(uom) as uom,SUM(amount)
from yourtable
group by matnum,uom