为什么SQL中的max函数返回多个值

Question

我想展示薪水最高的球员。

select  max(Salary) as highest_salary, p.[Last name]
from tbl_PlayersTable as p, tbl_team as t
where p.Team = t.TeamID
and TeamID = 1000
Group by p.[Last name]

输出为：

highest_salary  Last Name
   8000          Bosh
   7000          Wade
   6000          James

我只想显示（8000波什，因为他是薪水最高的球员）。

Answer 1

您不需要MAX或GROUP BY ，只需将TOP 1与ORDER BY Salary DESC 。 像这样：

select TOP (1) Salary as highest_salary, p.[Last name]
from tbl_PlayersTable as p, tbl_team as t
where p.Team = t.TeamID
 and TeamID = 1000
ORDER BY Salary  DESC

Answer 2

您正在将值分组（请参阅最后的分组依据），因此您的max函数将计算每个组的最大值。 如果要使用绝对最大值，请删除分组。

Answer 3

无需group by甚至max ：

select  top 1 Salary
,       [Last name]
from    tbl_PlayersTable
where   TeamID = 1000
order by
        salary desc

Answer 4

因为您使用group by p.[Last name]所以查询将为其找到的每个不同的Last name获得max(Salary) 。 因此，如果要基于所有Last name获得max(Salary) ，则必须删除group by

Answer 5

您将需要采用前1个值

  select TOP (1) Salary as maxsalary, p.[Last name]
   from tbl_PlayersTable as p 
   Inner join  tbl_team as t on  p.Team = t.TeamID
  where TeamID = 1000
  ORDER BY Salary  DESC