删除包含子查询的 sql 查询中的冗余

Question

假设我们有一个 table 方案

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

我正在尝试获取排名最高的学生信息（ID 和姓名）（按数学成绩和英语成绩的最高总和排序）。可能有几个打领带的学生，我们要他们所有人。我考虑这样做的方法是使用子查询来获得具有分数总和的 table，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)

这可行，但似乎非常多余且效率不高。

我刚开始学习 sql 语言，希望能对这个问题有一些见解！

Answer 1

搭配使用

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

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

Answer 3

这应该可以完成，您添加了一个不必要的步骤。

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)

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