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  • sql 分组后查询最大所有列信息

    CREATE TABLE students 
        (course varchar(10),
            stu_name varchar(10),
            city    varchar(10),
            score   int
        )
    
    insert into students values('数学','Jack','Tianjin',80);
    insert into students values('数学','Jordan','Tianjin',80);
    insert into students values('数学','James','Beijing',55);
    insert into students values('英语','Jack','Tianjin',90);
    insert into students values('英语','Jordan','Tianjin',60);
    insert into students values('英语','James','Beijing',100);
    insert into students values('语文','Jack','Tianjin',60);
    insert into students values('语文','Tom','Tianjin',77);
    insert into students values('语文','Jordan','Tianjin',68);
    
    DELETE from students
    
    SELECT * from students
    --最大是多条的时候取一条
    select  *
        from (
            select course,stu_name,city,score,ROW_NUMBER() over(partition by course order by score desc) as rn
            from students
            ) a
        where a.rn <=1;  
    --最大是多条的时候都取
    select 
    --a.course,a.score,b.stu_name,b.city,b.course course1,b.score score1 
    b.*
    from 
    (
    SELECT course,max(score) score from students GROUP BY course
    ) a
    LEFT JOIN
    students b on
    a.course=b.course and a.score=b.score;
    

      

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  • 原文地址:https://www.cnblogs.com/liuqiyun/p/8087211.html
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