Question

我这里有这张表

CONCAT(Nome,'',Cognome) Interno value
FRANCESCA BIFULCO       1           0
FRANCESCA BIFULCO       1          84
FRANCESCA BIFULCO       1A        570
FRANCESCA BIFULCO       1A        972
RICCIARDELLI            2        1276
RICCIARDELLI            2        1320

我想要做的就是选择每个用户的最大值。（如您所见，每个用户多次出现。）

例如：

FRANCESCA BIFULCO | 1 | 0
FRANCESCA BIFULCO | 1 | 84

想要的结果：

FRANCESCA BIFULCO | 1 | 84

我尝试了什么：

select a.ut, max(value)
from (
select Utenti_Condomini.ID_Condominio,CONCAT(Nome,' ', Cognome) as ut, Utenti_Condomini.Interno as i, Greatest(Max(Val_Primo), Max(Val_Secondo), Max(Val_Terzo), Max(Val_Quarto) )as value 
from Letture_Acqua, Utenti_Condomini 
where ID = 19 
and Utente = CONCAT(Nome,' ', Cognome)
and ID = ID_Condominio and Interno = Internus 
group by Utente, Internus, Anno 
order by id_user+0
)a 
group by a.ut, a.i

注意： 内部查询返回照片中显示的内容。

非常感谢你的帮助！

Answer 1

将yourTableName替换为您要求的任何表格

SELECT CONCAT(Nome,' ',Cognome),interno,MAX(value) FROM yourTableName GROUP BY Nome,Cognome,interno;

Answer 2

<强>模式

create table test(
fullname varchar(100),
category char(5),
value int
);
insert into test values("TATA BIRLA", "1",0);
insert into test values("TATA BIRLA", "1",80);
insert into test values("TATA BIRLA", "1A",570);
insert into test values("TATA BIRLA", "1A",972);

SQL查询

SELECT fullname, max(value)
from test
group by fullname,category;

选择2个相同行MYSQL之间的最大值

2 个答案: