Question

我正在尝试查找查询中的最大总数，并且只能显示所有条目的总数。到目前为止我已编码。

SELECT id "ID number", name "Name", SUM(quantity*cost) "Total"
FROM distributioncenter NATURAL JOIN inventory 
GROUP BY id, name

同样，这会为所有人提取总数，但我无法弄清楚如何获得最大总数。

Answer 1

我认为您希望MAX（）返回所有

的最高值

Answer 2

编辑：

 select max(total) as maximum_value from
(SELECT id "ID number", name "Name", SUM(quantity*cost) "Total"
 FROM distributioncenter NATURAL JOIN inventory 
 GROUP BY id, name  
)

如果嵌套查询不起作用并生成不同的表。

    create table want as  
    SELECT id "ID number", name "Name", SUM(quantity*cost) "Total"
         FROM distributioncenter NATURAL JOIN inventory 
         GROUP BY id, name ;  

select max(total) as maximum_value from want;

Answer 3

您使用的是哪种SQL？我想你正在寻找一个嵌套的SELECT，许多SQL方言都支持它。在这种情况下，答案是：

SELECT MAX(Total) FROM (
    SELECT id "ID number", name "Name", SUM(quantity*cost) "Total"
    FROM distributioncenter NATURAL JOIN inventory 
    GROUP BY id, name
) AS XX

选择最大总和

3 个答案: