本文介绍了SQL:查找每组的最大记录的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
<块引用>可能的重复:
检索每组中的最后一条记录
我有一张表,其中包含三个字段和数据.
<前>名称 , 顶部 , 总计猫 , 1 , 10狗 , 2 , 7猫 , 3 , 20马 , 4 , 4猫 , 5 , 10狗 , 6 , 9我想为每个Name
选择Total
值最高的记录,所以我的结果应该是这样的:
我尝试按名称顺序按总数分组,但它给出了按结果分组的最高记录.谁能指导我好吗?
解决方案
select名称、顶部、总计从有的在哪里Total = (select max(Total) from sometable i where i.Name = sometable.Name)
或
选择名称、顶部、总计从有的内部联接 (选择 max(Total) Total, Name从某个表按名称分组) 作为 max.Name = sometable.Name 和 max.Total = sometable.Total 上的最大值
Possible Duplicate:
Retrieving the last record in each group
I have one table, which has three fields and data.
Name , Top , Total cat , 1 , 10 dog , 2 , 7 cat , 3 , 20 horse , 4 , 4 cat , 5 , 10 dog , 6 , 9
I want to select the record which has highest value of Total
for each Name
, so my result should be like this:
Name , Top , Total cat , 3 , 20 horse , 4 , 4 Dog , 6 , 9
I tried group by name order by total, but it give top most record of group by result. Can anyone guide me, please?
解决方案
select
Name, Top, Total
from
sometable
where
Total = (select max(Total) from sometable i where i.Name = sometable.Name)
or
select
Name, Top, Total
from
sometable
inner join (
select max(Total) Total, Name
from sometable
group by Name
) as max on max.Name = sometable.Name and max.Total = sometable.Total
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