将两个内连接查询合并到一个过程中答案

【问题标题】：Combine two inner join queries into one procedure将两个内连接查询合并到一个过程中
【发布时间】：2014-03-27 14:51:26
【问题描述】：

        SELECT TOP 15
      us.MxitId AS TransactionCreatedBy, COUNT(t.CreatedBy) Total
FROM [User] us
INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId
Where ChildGender = 'Male'
GROUP BY us.MxitId, t.ChildGender 
ORDER BY 2 desc





SELECT TOP 15
      us.MxitId AS TransactionCreatedBy, COUNT(t.CreatedBy) Total
FROM [User] us
INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId
Where ChildGender = 'Female'
GROUP BY us.MxitId, t.ChildGender 
ORDER BY 2 desc

我正在尝试将上述两个程序合二为一。

请任何人帮助我，我正在获取 us.MxitId 列的重复值。

 Select   us.MxitId AS TransactionCreatedBy,
(SELECT TOP 15
         COUNT(t.CreatedBy) TotalMale where ChildGender = 'Male') ,

          ( Select top 15 COUNT(t.CreatedBy) TotalFemale where ChildGender = 'Female')


    FROM [User] us
    INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId

    GROUP BY us.MxitId, t.ChildGender 
    ORDER BY 2 desc

【问题讨论】：

你想如何组合它们？男孩的前 15 名用户可能与女孩的前 15 名用户完全不同。或者，它们可能是相同的列表，但顺序不同。向我们展示您希望输出的样子。
嗨，两种情况下的用户都是一样的，如果用户没有记录任何女性数据，我想说 0，反之亦然

标签： sql sql-server stored-procedures inner-join

【解决方案1】：

此查询应该可以在没有重复 MxitId 的情况下获取性别计数。

SELECT TOP 15
      us.MxitId AS TransactionCreatedBy
, COUNT(t.CreatedBy) AS Total
, SUM(CASE WHEN ChildGender = 'Female' THEN 1 ELSE 0 END) AS FemaleCount
, SUM(CASE WHEN ChildGender = 'Male' THEN 1 ELSE 0 END) AS MaleCount
FROM [User] us
INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId
GROUP BY us.MxitId
ORDER BY 2 desc

【讨论】：

在输入之前在这个评论框中说：请避免像 +1 这样的 cmets 和谢谢.. ;-)

【解决方案2】：

 SELECT TOP 15
      us.MxitId AS TransactionCreatedBy, 
    sum(case when ChildGender = 'Male' then 1 else 0 end) TotalMale
      ,sum(case when ChildGender = 'feMale' then 1 else 0 end) TotalFeMale
FROM [User] us
INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId

GROUP BY us.MxitId, t.ChildGender

【讨论】：

Msg 102, Level 15, State 1, Line 3 ')' 附近的语法不正确。消息 102，级别 15，状态 1，第 3 行“TotalMale”附近的语法不正确。消息 102，级别 15，状态 1，第 4 行“TotalFeMale”附近的语法不正确。
把结束放在括号内
嗨，数据仍在重复
我不知道它们的关系表结构。

【解决方案3】：

您可以使用row_number()：

SELECT TransactionCreatedBy, ChildGender, Total
FROM (SELECT us.MxitId as TransactionCreatedBy, t.ChildGender, COUNT(t.CreatedBy) as Total,
             row_number() over (partition by t.ChildGender order by COUNT(t.CreatedBy) desc
                               ) as seqnum
      FROM [User] us INNER JOIN
           [Transaction] t
           ON t.CreatedBy = us.UserId
      GROUP BY us.MxitId, t.ChildGender 
     ) t
WHERE seqnum <= 15
ORDER BY Total desc;

我还在select 列表中添加了性别，这样您就可以看到哪些行来自哪个表。

如果您想将两个计数放在同一个表中，然后以某种方式进入前 15 名：

      SELECT us.MxitId as TransactionCreatedBy, COUNT(t.CreatedBy) as Total,
             sum(case when t.ChildGender = 'Male' then 1 else 0 end) as TotalMales,
             sum(case when t.ChildGender = 'Female' then 1 else 0 end) as TotalFemales
      FROM [User] us INNER JOIN
           [Transaction] t
           ON t.CreatedBy = us.UserId
      GROUP BY us.MxitId, t.ChildGender 
      ORDER BY COUNT(t.CreatedBy) desc
      LIMIT 15;

【讨论】：

【解决方案4】：

写成：

select top 15 us.MxitId AS TransactionCreatedBy,
        count(case ChildGender when 'Male' then 1 else null end) as MaleCount,
        count(case ChildGender when 'Female' then 1 else null end) as FemaleCount
from [User] us
INNER JOIN [Transaction] t ON t.CreatedBy = us.UserId
GROUP BY us.MxitId

【讨论】：