Question

下面是我的桌子，人口是每个城市的人口。

City state country population
c1   s1   co1   100000
c2   s1   co1   100000
c3   s1   co1   100000
c11  s2   co1   100000
c12  s2   co1   100000

我需要如下输出

s1 300000
s2 200000
co1 500000

任何人都可以使用sql server或Teradata帮助实现这一目标

Answer 1

您可以使用apply：

select col, sum(population)
from table t cross apply
     ( values (state, population), (country, population) 
     ) tt(col, population)
group by col;

您还可以将union all用于其他DBMS：

select t.state, sum(t.population)
from table
group by t.state
union all
select t.country, sum(t.population)
from table
group by t.country;

Answer 2

apply如yogesh所说的那样工作，但这可能更容易理解

 select 'state' as t, state as s, sum(population) as total
 from table_you_did_not_name
 group by state

 union all

 select 'country' as t, country as s, sum(population) as total
 from table_you_did_not_name
 group by country

Answer 3

您需要2个不同的分组，然后将它们与UNION组合：

select state column1, sum(population) column2
from tablename
group by state
union all
select country, sum(population)
from tablename
group by country

Answer 4

一个简单的解决方案是合理地计算它们并结合在一起

select  state, sum(population)
from table 
group by  state
union all 
select country,  sum(population)
from table 
group by  country

结合两组不同的查询

4 个答案: