Sql server 使用join从两个表中获取不同的数据

下面是我的问题。我从Employee表中获取socail sercurity no，并将其与child_excel表匹配。使用它，我获得雇员ID，并将其与EmployeeCh表（具有雇员ID）匹配。该员工有两个孩子，因此当我输入性别条款时，我会为每个孩子获得4条记录，每个孩子有不同的记录（即男性、女性）。我只想要2行，每个孩子1行，每个孩子有各自的性别

SELECT distinct 
      [SSN],
      empch2.GenderID,
      gen.Name1
  FROM [child_excel] as t
  INNER JOIN Employee as empch on t.SSN = empch.SocialSecurityNo
  INNER JOIN EmployeeCh  as empch2 on empch.ID = empch2.EmployeeID  
  INNER JOIN Gender as gen on empch2.GenderID = gen.ID

我收到的O/p为

12345  1  Male
12345  2  Female
99999  1  Male
99999  2  Female

预期产量为

12345   1   Male
99999   2   Female

但是当我在连接中添加名字时，它会给出正确的输出。我不想用名字

SELECT distinct 
          [SSN],
          empch2.GenderID,
          gen.Name1
      FROM [child_excel] as t
      INNER JOIN Employee as empch on t.SSN = empch.SocialSecurityNo
      INNER JOIN EmployeeCh  as empch2 on empch.ID = empch2.EmployeeID and  t.First_Name= empch2.FirstName  
      INNER JOIN Gender as gen on empch2.GenderID = gen.ID

使用行号（）

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SSN不一样。分组中需要哪个SSN？我希望有尽可能多的不同记录，但每个唯一行只有一条记录。那么，哪一行无关紧要？我希望O/P为12345 1男99992女我每次获得一条记录数据。我想要尽可能多的不同的记录。但根据您的样本数据，它会给出正确的结果，并且@user2998990也是不同的

Select * from (

SELECT distinct 
      [SSN],
      empch2.GenderID,
      gen.Name1,
      ROW_NUMBER()OVER(PARTITION BY [SSN] ORDER BY empch2.GenderID)RN
  FROM [child_excel] as t
  INNER JOIN Employee as empch on t.SSN = empch.SocialSecurityNo
  INNER JOIN EmployeeCh  as empch2 on empch.ID = empch2.EmployeeID and  t.First_Name= empch2.FirstName  
  INNER JOIN Gender as gen on empch2.GenderID = gen.ID )T
  WHERE T.RN = 1