Question

在下面的select语句中我有707行

select detail_serial, Price from apa_invoice_detail

我还有另一个选择语句

 Select   max(detail_serial)
         ,asc_item.item_name_2
         ,asc_group.group_name_2
 From apa_invoice_detail 
 inner join asc_item on asc_item.item_id=apa_invoice_detail.item_id
 inner join asc_group on asc_group.group_id=asc_item.group_id
 Group by  asc_item.item_name_2, asc_group.group_name_2

这个给了我197行

我需要从第二个语句中的detail_serial的第一个语句中获取价格（仅适用于197行）

我试过了：

select detail_serial, Price from apa_invoice_detail where detail_serial in
    (Select max(detail_serial)
           ,asc_item.item_name_2
           ,asc_group.group_name_2
   From apa_invoice_detail 
   inner join asc_item on asc_item.item_id=apa_invoice_detail.item_id
   inner join asc_group on asc_group.group_id=asc_item.group_id
   Group by  asc_item.item_name_2, asc_group.group_name_2)

但它给了我＆＃34;当子查询没有用EXISTS引入时，只能在选择列表中指定一个表达式。＆＃34;

我该怎样解决这个问题？

Answer 1

尝试删除内部select语句中的列

select detail_serial, Price from apa_invoice_detail where detail_serial in
(Select max(detail_serial)
     From apa_invoice_detail 
     inner join asc_item on asc_item.item_id=apa_invoice_detail.item_id
     inner join asc_group on asc_group.group_id=asc_item.group_id
     Group by  asc_item.item_name_2, asc_group.group_name_2)

Answer 2

使用EXISTS代替IN。

;WITH SecondQueryResults AS
(
    Select   max(detail_serial) detail_serial
                , asc_item.item_name_2
                , asc_group.group_name_2
        From apa_invoice_detail 
             inner join asc_item on asc_item.item_id=apa_invoice_detail.item_id
             inner join asc_group on asc_group.group_id=asc_item.group_id
        Group by  asc_item.item_name_2, asc_group.group_name_2
)
select 
    detail_serial, 
    Price 
from 
    apa_invoice_detail T
where 
    EXISTS (SELECT 'serial exists on query result' FROM SecondQueryResults AS S WHERE S.detail_serial = T.detail_serial)

...或者只选择detail_serial子查询中的1列（IN）。

我需要在另一个select中选择（sql server）

2 个答案: