Question

假设我们有一个方案表

student(id (primary key), name, math_score, english_score)

我正在尝试获得排名最高的学生信息（ID和姓名）（按数学分数和英语分数的最高总和排序）。可能有几个学生打领带，我们想要所有这些。我想这样做的方法是使用子查询来获得一个包含总和的表，然后找到具有最高总和的id，名称。

SELECT s.id, s.name
FROM (SELECT s.id, s.name, s.math_score+s.english_score as sum
      FROM student s) s
WHERE s.sum = (SELECT max(s.sum)
               FROM (SELECT s.id, s.name, s.math_score+s.english_score as sum
                     FROM student s) s)

这有效，但似乎非常多余且效率不高。

我刚开始学习sql语言，我很欣赏这个问题的一些见解！

Answer 1

使用WITH TIES

create table #student(
    id int primary key identity(1,1), 
    name varchar(50), 
    math_score decimal, 
    english_score decimal
)

insert into #student
values
('Tom', 90, 90),
('Dick', 70, 70),
('Harry', 80, 100)

select TOP(1) WITH TIES
    id, 
    name, 
    math_score, 
    english_score, 
    math_score + english_score as ScoreRank
from #student
order by
    math_score + english_score desc

给出答案：

id|name|math_score|english_score|ScoreRank
1|Tom|90|90|180
3|Harry|80|100|180

Answer 2

这应该完成它，你在不必要的步骤中添加。

select id, 
       name, 
       math_score+english_score as total_score
from student
where math_score+english_score=(select max(math_score+english_score)
                                from student)

Answer 3

        SELECT id, name, math_score+english_score as 'sum'
        FROM student
        Order by math_score+english_score DESC;

删除包含子查询的sql查询中的冗余

3 个答案: