Question

预警，我是一个新手，所以要温和。我需要从一组值中得到 qty 的SUM，然后是前5个MAX sum qty 从那个名单。但是我需要从最终列表中省略一个NULL值。

Answer 1

我会在没有子查询的情况下执行此操作：

select game_name, sum(qty) AS total 
from sales
where game_name is not null
group by game_name
order by total desc
limit 5;

Answer 2

试试这个：

SELECT game_name,
       max(total) AS total  
FROM ( select game_name,
              sum(qty) AS total
       FROM sales
       GROUP BY game_name
     ) AS RANK
where game_name is not null
group by game_name
order by total desc limit 5 ;

它将删除任何null游戏，按总降序排序，它会为您提供前5行。

如何从表中获取一组值的SUM，然后获得这些值的MAX并回显5个最高值

2 个答案: