Question

我需要在2个不同的表上计算城市出现的次数。一个表是供应商表，其中包含vendor_id，城市和州。第二个表是具有消费者ID，城市和州的消费者。我的查询需要返回名称匹配的州，供应商城市的城市数和消费城市的数目。

我已经尝试了几种不同的方法，例如相交和并集，但都无法做到。我的最新文章在下面，但不确定我在做什么错

   SELECT S.State
   ,C.City
  ,count(S.City) as Number_Of_Suppliers
  ,count(C.City)  as Number_Of_Consumers
  from dbo.Tb_Supplier S                     
  left outer Join dbo.Tb_Consumer C
On  S.STATE = C.STATE
AND S.City = C.City
 group by S.state
  ,C.City

Answer 1

使用union all和group by：

select state, city, sum(supplier)
        sum(supplier) as Number_Of_Suppliers,
        sum(consumer) as Number_Of_Consumers
from ((select state, city, 1 as supplier, 0 as consumer
       from dbo.Tb_Supplier s
      ) union all                    
      (select state, city, 0 as supplier, 1 as consumer
       from dbo.Tb_Consumer c
      )
     ) sc
group by state, city

从2个不同的表格中计算城市和州

1 个答案: