如何在SQL Server 2008中从Avg中查找Max

你需要表名别名如Tname

select max(total_price_new) 
from  ( 
  select avg(Total_Price) as total_price_new, Document_Ref 
  from  TBL_Sales
group by Document_Ref
)  Tname 

别名 ( q

select max(q.total_price_new) 
  from  ( select avg(Total_Price) as total_price_new, Document_Ref 
            from TBL_Sales
           group by Document_Ref) as q;

This 参考资料可能会有帮助。

select
    max(total_price_new) 
from
    (select
         avg(Total_Price) as total_price_new, 
         Document_Ref  
     from
         TBL_Sales
     group by
         Document_Ref) as T

此操作不需要子查询:

select top (1) avg(Total_Price) as total_price_new
from TBL_Sales
group by Document_Ref
order by total_price_new desc;

Document_Ref 平均值最高。