Question

朋友我被困在存储过程中。我无法显示不同的记录。

我有一个名字USERS和Photos。两者都是使用userID的内连接。

由于表Photos有多条记录，因此重复搜索结果。朋友可以帮我解决这个问题吗？

存储过程：

ALTER PROCEDURE dbo.homesearch
   @gender varchar(6),
   @age int,
   @age2 int,
   @religion varchar(50),
   @status varchar(11),
   @Country varchar(50),
   @City varchar(50)
AS
   SELECT 
       users.userID, photos.filename, users.userName,
       users.FirstName, users.LastName, users.nationality, 
       users.Country, users.City, users.age, users.status 
   FROM 
       users 
   INNER JOIN 
       photos ON users.userID = photos.userID
   WHERE 
      (users.age >= @age) AND (users.age <= @age2) 
      AND (users.gender = @gender) AND (users.religion = @religion) 
      AND (users.status = @status) AND (users.Country = @Country) 
      AND (users.City = @City)

   RETURN

Answer 1

您可以使用CROSS APPLY

执行此类操作

SELECT u.userID
      ,u.userName
      ,P.filename
      ,u.FirstName
      ,u.LastName
      ,u.nationality 
      ,u.Country
      ,u.City
      ,u.age
      ,u.status 

FROM  users u
        CROSS APPLY
                  (
                  SELECT TOP 1 photos.filename
                  FROM photos 
                  WHERE u.userID = userID
                  ORDER BY photos.SomeColumn   --<-- Pick a column here
                  )p
WHERE (u.age >= @age)      AND (u.age <= @age2) 
AND   (u.gender = @gender) AND (u.religion = @religion) 
AND   (u.status = @status) AND (u.Country = @Country) 
AND   (u.City = @City)

从用户表格中的每个用户中选择一个您想要从照片表中选择哪个TOP 1文件名的列。

或使用CTE

;With P_CTE
AS
 (
 SELECT TOP UserID, photos.filename,
        rn = ROW_NUMBER() OVER (PARTITION BY UserID ORDER BY UserID)
 FROM photos
 )
SELECT users.userID, P_CTE.filename, users.userName,
       users.FirstName, users.LastName, users.nationality, 
       users.Country, users.City, users.age, users.status 
FROM   users INNER JOIN  P_CTE 
ON     users.userID = P_CTE.userID
WHERE  (users.age >= @age) AND (users.age <= @age2) 
AND    (users.gender = @gender) AND (users.religion = @religion) 
AND    (users.status = @status) AND (users.Country = @Country) 
AND    (users.City = @City)
AND    P_CTE.rn = 1

Answer 2

修改您的选择查询： -

SELECT users.userID, photos.filename, users.userName,
   users.FirstName, users.LastName, users.nationality, 
   users.Country, users.City, users.age, users.status 
FROM users INNER JOIN photos 
    ON users.userID = photos.userID
WHERE (users.age >= @age) AND (users.age <= @age2) 
    AND (users.gender = @gender) AND (users.religion = @religion) 
    AND (users.status = @status) AND (users.Country = @Country) 
    AND (users.City = @City) 
GROUP BY users.userID, photos.filename, users.userName,
   users.FirstName, users.LastName, users.nationality, 
   users.Country, users.City, users.age, users.status

它将返回独特的结果。

Answer 3

SELECT users.userID, photos.filename, users.userName,
   users.FirstName, users.LastName, users.nationality, 
   users.Country, users.City, users.age, users.status 
FROM users INNER JOIN (SELECT DISTINCT userID FROM photos) AS P 
ON users.userID = P.userID

Answer 4

这里的想法是减少你的照片表中的条目，因为每个用户都有很多照片。在我的示例中，我使用max(filename)来获取名称最长的名称，但您可以在此处使用其他条件：

SELECT users.userID, P.filename, users.userName,
   users.FirstName, users.LastName, users.nationality, 
   users.Country, users.City, users.age, users.status 
FROM users INNER JOIN 
 (SELECT userID, max(filename) as filename 
  FROM photos
  GROUP BY userID) AS P 
ON users.userID = P.userID
WHERE (users.age >= @age) AND (users.age <= @age2) 
   AND (users.gender = @gender) AND (users.religion = @religion) 
   AND (users.status = @status) AND (users.Country = @Country) 
   AND (users.City = @City)

Answer 5

请清楚点阿里。

您的数据显示的内容类似于..

userID      userName ......... filename
1           ABC                c:/phot1.png
1           ABC                c:/phot2.png
1           ABC                c:/phot2.png

如果我是正确的，那么他们有两种可能的方式来显示您的数据以使您的记录与众不同。

<强>第一

  userID      userName ......... filename
    1           ABC                c:/phot1.png,c:/phot2.png,c:/phot2.png

这可以通过for xml path('') OR COALESCE

来实现

<强>第二
只显示一张照片：

userID      userName ......... filename
        1           ABC                c:/photo1.png

这可以通过应用一些照片条件来实现。

SQL Server：选择具有内连接和where子句的不同记录

5 个答案: