试图限制数量显示在mysql结果中

Question

我有一个存储id，项目，食物类型，图像和价格的表

我想将结果限制为商店中销售的每种类型之一，例如狗粮，猫粮，dvd降序 mysql数据库中保存的示例 表：Nunca

id      item                    type        image   price
=========================================================
1       Pedigree Pouches        dog food    img1    $4.99
2       Cesar Classic Selection dog food    img2    $3.99
3       Meaty Strips Chicken    dog food    img3    $2.99
4       Jelly Fish Selection    cat food    img4    $1.99
5       Bananas                 fruit       img5    $2.84
6       Celery                  vegetables  img6    $5.99
7       Apple                   fruit       img7    $0.95
8       Pineapple Juice         Soft drink  img8    $0.99
9       Oranges                 fruit       img9    $1.99
10      Cabbage                 vegetables  img10   $0.99
11      Suicide Squad           dvd         img11   $12.99

最终结果应该来自查询

id      item                    type        image   price
==========================================================
11      Suicide Squad           dvd         img11   $12.99
10      Cabbage                 vegetables  img10   $0.99
9       Oranges                 fruit       img9    $1.99
8       Pineapple Juice         Soft drink  img8    $0.99
4       Jelly Fish Selection    cat food    img4    $1.99
3       Meaty Strips Chicken    dog food    img3    $2.99

我尝试了各种mysql查询，但无济于事

Answer 1

典型方法使用相关子查询：

select n.*
from nunca n
where n.id = (select max(n2.id) from nunca n2 where n2.type = n.type);

这将选择每种类型的最后一行。

Answer 2

select * from t where 
id in(select max(t.id) id from t group by t.type) 
order by id desc

我想可以有窗口或连接替代品，但这个似乎适合这个目的。