mysql - 按类别选择行

Question

我只需要按类别选择一行，并且选择的行必须是最低价格。

我有这个:

结果必须是:

Answer 1

首先您需要获得每堂课的最低价格:

select Class, min(price) as minimum from myTable group by Class

然后为了向其中添加其余的列，您需要将它们连接在一起:

select b.* from (
  select Class, min(price) as minimum from myTable group by Class
) as a inner join myTable as b on a.class = b.class and a.minimum = b.price