select a.订单ID, 客户ID, ${if(len(col)=0,"",""+col+",")} sum(数量) as 数量, sum(进价) as 进价 FROM S订单 a inner join S订单明细 b on a.订单ID = b.订单ID group by a.订单ID,客户ID ${if(len(col)=0,"",","+col+"")}