Question

我有一个客户群组表，我想选择群组的名称（以及另一个名为Notes的值）但是group by不允许我这样做，即使整个群组具有相同的名称和备注值

select cg.idCustomerGroup, 
       sum(case when c.type = 'child' then 1 else 0 end) as Children,
       sum(case when c.type = 'adult' then 1 else 0 end) as Adults,
       sum(case when c.type = 'senior' then 1 else 0 end) as Seniors
from CustomersGroups cg
   inner Join CustomersInGroup cig
      on cg.idCustomerGroup = cig.idCustomerGroup
   inner Join Customers c
      on c.idCustomer = cig.idCustomer
Group by cg.idCustomerGroup

Answer 1

您必须在GROUP BY：

中加入论坛的名称和备注

select cg.idCustomerGroup, cg.Name, cg.Notes,
       sum(case when c.type = 'child' then 1 else 0 end) as Children,
       sum(case when c.type = 'adult' then 1 else 0 end) as Adults,
       sum(case when c.type = 'senior' then 1 else 0 end) as Seniors
from CustomersGroups cg
   inner Join CustomersInGroup cig
      on cg.idCustomerGroup = cig.idCustomerGroup
   inner Join Customers c
      on c.idCustomer = cig.idCustomer
Group by cg.idCustomerGroup, cg.Name, cg.Notes

如何在sql中通过id从组中获取名称

1 个答案: