Question

所以说我在Oracle SQL中有两个表（实际上不是数据但是为了方便起见我应该强调我的问题）

Table1仅包含Order_id和Order_quantity，Table2仅包含Order_id和Order_price

然后我加入他们如下

SUM(variable_name) From Table_Name

基本上我想要两个额外的列，一个作为两个表中列的乘积，另一个作为我的联合表中该列的总和（因此每个条目都是相同的）。但是你需要

Select T1.Order_id,
    T1.Order_quantity,
    T2.Order_price,
    T1.Order_quantity*T2.Order_price As "Order_amount",
    Sum(Order_amount) from New_Table As "Total_Sales"
    from (Table1 T1
    inner join Table2 T2
    on T1.Order_id = T2.Order_id) As New_Table

我可以为新表分配变量名称，然后参考。我尝试了以下但我得到的SQL命令没有正确结束错误

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感谢您的帮助，道歉，因为我目前对SQL非常天真，

Answer 1

我想你只想要一个窗口功能：

select T1.Order_id, T1.Order_quantity, T2.Order_price,
       T1.Order_quantity*T2.Order_price As order_amount,
       sum(T1.Order_quantity*T2.Order_price) over () As Total_Sales
from Table1 T1 inner join
     Table2 T2
     on T1.Order_id = T2.Order_id

您无法在order_amount中重复使用别名select。您需要重复表达式 - 或使用子查询或CTE来定义它。

Answer 2

如果您的 DBMS 没有窗口功能支持，那么您可以使用subquery代替

select order_id, Order_quantity,
       (select t1.Order_quantity * t2.Order_price 
        from table2 t2
        where t2.Order_id = t1.Order_id) as Order_amount,
       (select sum(t1.Order_quantity * t2.Order_price) 
        from table2 t2
        where t2.Order_id = t1.Order_id) as Total_Sales
from table1 t1;

连接表中的Sum列并添加为SQL列

2 个答案: