如何获取每科得满分的学生的名字？

Question

我有下表

 Name  |  Subject  | Marks
 --------------------------
 a        M          20
 b        M          25  
 c        M          30
 d        C          44 
 e        C          45
 f        C          46 
 g        H          20

这里我有一个“学生”表，我想获取获得的学生的姓名
学生表中每个科目的最高分数，如下输出。

 Name | Subject | Marks  
 c        M        30
 f        c        46
 g        h        20

Answer 1

您可以使用 ROW_NUMBER 函数仅返回每个主题的“最佳”行：

SQL 小提琴

MS SQL Server 2008 架构设置:

CREATE TABLE Student
    ([Name] varchar(1), [Subject] varchar(1), [Marks] int)
;

INSERT INTO Student
    ([Name], [Subject], [Marks])
VALUES
    ('a', 'M', 20),
    ('b', 'M', 25),
    ('c', 'M', 30),
    ('d', 'C', 44),
    ('e', 'C', 45),
    ('f', 'C', 46),
    ('g', 'H', 20)
;

查询1：

SELECT Name, Subject, Marks
FROM(
  SELECT *, ROW_NUMBER()OVER(PARTITION BY Subject ORDER BY Marks DESC) rn
    FROM dbo.Student
)X
WHERE rn = 1

结果:

| NAME | SUBJECT | MARKS |
--------------------------
|    f |       C |    46 |
|    g |       H |    20 |
|    c |       M |    30 |

Answer 2

您也可以使用其他函数和cte来获得结果..

例如：1

select B.Name,
       A.Subject,
       B.Marks
from ( select Subject,
              max(Marks) as High_Marks
         from Student
       group by Subject
     ) a
  join Student b
    on a.subject = b.subject
   and a.high_Marks = b.Marks

例如：2：使用cte和dense_rank函数

;WITH cte

AS

(

SELECT

   [Name],

   [Subject],

   [Marks],

   dense_rank() over(partition BY [Subject] order by [Marks] DESC) AS Rank

FROM Student

)

SELECT * FROM cte WHERE Rank = 1;

Answer 3

这个基本查询应该适合您的要求。

SELECT Name, Subject, Max(Marks)
FROM Student
GROUP by Subject;

在SQLFiddle

中尝试过

注意：使用SQLite进行检查

Answer 4

SQL> with cte as
  2  (
  3  select name, subject, marks, dense_rank() over (partition by subject order
by marks desc) rnk
  4  from student)
  5  select name, subject, marks
  6  from cte
  7  where rnk=1;

N S      MARKS
- - ----------
f c         46
c m         30

SQL>

Answer 5

SELECT

Max（名称）作为名称，主题，Max（标记）作为标记

FROM

学生

group by

主题

Answer 6

类似的问题：

编写一个查询来显示每个科目获得最高分的学生姓名，并按科目名称升序排列。

如果有多个礼帽，请按字母顺序显示他们的名字。

显示为subject_name 和student_name。

O/P：

• 第一列 - subject_name
• 第二列 - 学生姓名

此问题的解决方案：

SELECT subject_name,student_name 
    from Student s 
        inner join Mark m on s.student_id=m.student_id
        inner join Subject su on m.subject_id=su.subject_id
        inner join (select subject_id
                          ,max(value) as maximum 
                              from Mark ma group by subject_id
                    ) highmarks 
                        ON highmarks.subject_id=m.subject_id 
                            AND highmarks.maximum=m.value
            order by subject_name,student_name;

Answer 7

以下查询将完美运行：

select subject_name,student_name from student
inner join mark m using(student_id)
inner join subject su using(subject_id)
inner join (select subject_id,max(value) as maximum from mark m group by subject_id)
highestmark using(subject_id) where highestmark.maximum = m.value
order by subject_name,student_name;

Answer 8

此查询将起作用

select name,subject,marks from stud where marks in (select max(marks) from stud      group by subject) ;

Answer 9

通过使用 GROUP BY 和having子句，为您提供简单的sql查询来查找每个主题的最高分

SELECT Name, Subject, Marks from Student GROUP BY (Subject) HAVING Marks=max(Marks);

Answer 10

从学生中选择 *，其中分数 >= （来自学生的分数，其中主题 = 学生.主题）；