如何仅在mysql中获取min组行？

Question

Example1:

part of table test1:

name|mygroup| scale
----------------
ben | 1   | 1
tom | 1   | 2
jim | 2   | 1
tim | 2   | 2
..

the output should be:

name|mygroup| scale
----------------
ben | 1   | 1
jim | 2   | 1

I try:

select name,mygroup,min(scale) from test1 group by mygroup;

but it not give proper output.

Thanks

Answer 1

SELECT t.name, t.mygroup, t.scale
    FROM test1 t
        INNER JOIN (SELECT mygroup, MIN(scale) AS MinScale
                        FROM test1
                        GROUP BY mygroup) q
            ON t.mygroup = q.mygroup
                AND t.scale = q.MinScale