如何在 Hive 中使用别名？

Question

我正在尝试使用窗口函数查找唯一城市，我无法在此查询中使用别名

select branch,city,row_number() over(partition by city order by branch) as row_number from 
sales_report where row_number=1;

Error in query: cannot resolve '`row_number`' given input columns:

Answer 1

where 子句中不能有窗口函数。将其放入子查询中，然后进行过滤：

select * from
(
select branch,city,row_number() over(partition by city order by branch) as rn 
from sales_report 
) as t 
where rn = 1;