在where子句中使用currval

Question

有沒有辦法在where子句中獲得currval？ 我試圖檢查id = currval。我已經試過如下：

insert into order values( 
orderid_seq.nextval, 
SYSDATE , 
&quantity, 
&student_number, 
&room_number, 
&menu_item , 
(select item_cost * order_quantity 
FROM order_stock,order 
WHERE order_stock.menu_item = 
order.menu_item and 
order_id = orderid_seq.currval 
)); 

Answer 1

什麼數據庫這是？如果它是Oracle，並且orderid_seq是一個序列，則不可以在where子句中使用序列方法。

https://docs.oracle.com/database/121/SQLRF/pseudocolumns002.htm

Answer 2

您應該使用IN如果在orderid_seq.currval很多，正確的語法是：

select item_cost * order_quantity 
    FROM order_stock,order 
    WHERE order_stock.menu_item = 
    order.menu_item and 
    order_id IN (select order_id from orderid_seq.currval) 

更新

select item_cost * order_quantity 
    FROM order_stock,order 
    WHERE order_stock.menu_item = 
    order.menu_item and 
    order_id = (select order_id from Your_table where orderid_seq = 'currval')