如何在SQL Server 2000中聚合前5个数字

Question

嗨，我正面临一个问题，就是学生可以有超过5个科目，但我必须总共只有5个科目，总分为学生最高分。一种说明任何学生获得的前5个总分的总和的方法。

我如何继续请帮助我。提前谢谢。

Answer 1

在SQL 2000中，您需要使用子选择来确定具有相同ID的行数具有更高的标记。然后筛选其上方标记行数少于5的行：

select 
  ID, Sum(Mark)
From Table1 t
where 
(Select count(*) 
     from Table1 it 
    where it.id=t.id and it.mark>t.mark) <5
group by ID

Answer 2

遗憾的是，

ROW_NUMBER不在sql-server-2000中。但是，您可以使用子查询获得相同的结果。希望这是你正在寻找的：

SELECT s.studentid, SUM(s.total_marks)
FROM students s
WHERE s.sub_code IN (SELECT TOP 5 sub_code 
                     FROM students a 
                     WHERE a.studentid = s.studentid
                     ORDER BY total_marks DESC)
GROUP BY studentid

Working in fiddle

Answer 3

这是一个查询，每个学生只能获得5个最高分：

  SELECT studentID, total_marks, 
         row_number() OVER (PARTITION BY studentID, ORDER BY total_marks DESC) as rowN
  FROM studentTable
  WHERE rowN <= 5

所以得到总数：

SELECT studentID, SUM(total_marks)
FROM
(      
  SELECT studentID, total_marks, 
         row_number() OVER (PARTITION BY studentID, ORDER BY total_marks DESC) as rowN
  FROM studentTable
  WHERE rowN <= 5
) T
GROUP BY studentID