我如何通过 INNER JOIN 在查询中使用 Distinct

Question

我有一个来自我的产品和因素的查询以及要显示的因素项目。

在此查询中，我为用户显示来自因素的报告。

我的查询是：

WITH CTE AS
(
    SELECT 
        ROW_NUMBER() OVER (ORDER BY FactoriTems.datesave ASC) AS rn,
        FactoriTems.code, FactoriTems.replacement, 
        FactoriTems.suggcode, Factors.dateexport,
        Productions.descriptions, 
        FactoriTems.countt, FactoriTems.price, 
        FactoriTems.countt * FactoriTems.price AS 'total', 
        Productions.country             
    FROM 
        Productions 
    INNER JOIN 
        FactoriTems ON Productions.code = FactoriTems.code
    INNER JOIN 
        Factors ON Factors.gid = FactoriTems.gid
    WHERE 
        (FactoriTems.gid = @gid)
) 
SELECT * 
FROM CTE 
ORDER BY rn

这个查询是可以的，但是有一个问题，在Productions表中某些类别有两个或三个产品一个代码，当这个代码在factoritems表中时，我的结果集中显示了两行！

结果是：

rn	code	dateexport	descriptions	countt	price	total
1	aaa	12/24/2021	...	100	2	200
2	bbb	12/24/2021	...	200	3	600
3	ccc	12/24/2021	...	100	2	200
4	ddd	12/24/2021	...	200	3	600
5	ddd	12/24/2021	...	100	2	200
6	eee	12/24/2021	...	200	3	600

现在我如何才能只为'ddd' 产品代码显示一行？

我尝试使用DISTINCT，但出现错误。

我希望输出如下：

rn	code	dateexport	descriptions	countt	price	total
1	aaa	12/24/2021	...	100	2	200
2	bbb	12/24/2021	...	200	3	600
3	ccc	12/24/2021	...	100	2	200
4	ddd	12/24/2021	...	200	3	600
5	eee	12/24/2021	...	200	3	600

谢谢

Answer 1

试试这个代码：

WITH CTE AS
(SELECT ROW_Number() over (PARTITION BY FactoriTems.code ORDER by FactoriTems.datesave ASC) as rn,FactoriTems.code, 
        FactoriTems.replacement, FactoriTems.suggcode,Factors.dateexport,
        Productions.descriptions, FactoriTems.countt, FactoriTems.price, 
        FactoriTems.countt * FactoriTems.price AS 'total', Productions.country              
FROM Productions 
    INNER JOIN FactoriTems ON Productions.code = FactoriTems.code
    INNER JOIN Factors ON Factors.gid = FactoriTems.gid
WHERE (FactoriTems.gid = @gid)) 
SELECT  *   FROM CTE 
WHERE CTE.rn  = 1
ORDER BY rn

Answer 2

只是缺少内部查询中code 列的PARTITIN BY 子句。重写您当前的查询，例如

WITH CTE AS
 (SELECT ROW_NUMBER() OVER (PARTITION BY ft.code ORDER BY ft.datesave) AS rn0,         
         ft.code,
         ft.replacement,
         ft.suggcode,
         f.dateexport,
         p.descriptions,
         ft.countt,
         ft.price,
         ft.countt * ft.price AS total,
         p.country
    FROM Productions p
    JOIN FactoriTems ft
      ON p.code = ft.code
    JOIN Factors f
      ON f.gid = ft.gid
   WHERE (ft.gid = @gid))
SELECT ROW_NUMBER() OVER (ORDER BY datesave,code) AS rn, 
       code, replacement, suggcode, dateexport, descriptions,
       countt, price, total, country   
  FROM CTE 
 WHERE rn0 = 1
 ORDER BY rn

为了过滤掉每个不同分组code的重复项