Question

我的记录是：

name    |   id  |   AVG(point) as point
a       |   1   |   6
b       |   2   |   6
c       |   3   |   5
d       |   4   |   5
e       |   5   |   4
f       |   6   |   3
g       |   7   |   2

如何选择以下记录：

1.我想选择前3名记录，结果如下：

name    |   id  |   AVG(point) as point
a       |   1   |   6
b       |   2   |   6
c       |   3   |   5
d       |   4   |   5
e       |   5   |   4

2.我想选择不进入前三名的记录，结果如下：

name    |   id  |   AVG(point) as point
f       |   6   |   3
g       |   7   |   2

我该怎么办？

Answer 1

有几种方法可以做到这些。以下是使用in和not in的几个人。

对于前3名，您可以使用in：

select * 
from yourtable 
where point in (select distinct point 
                from yourtable 
                order by 1 desc 
                limit 3)

对于其他人，请改用not in：

select * 
from yourtable 
where point not in (select distinct point 
                from yourtable 
                order by 1 desc 
                limit 3)

其他方法包括exists not exists和distinct joins。

Answer 2

select * 
from yourtable as t1
inner join (select distinct point 
                from yourtable 
                order by 1 desc 
                limit 3) as t2
on t1.point = t2.point

对于问题的第二部分，请勿使用

desc

如何在mysql中选择所有重复记录

2 个答案: