提取Customer_Order表中不存在的产品ID

Question

我的查询select p.idProduct from customer_order c, product p where idProduct not in (select c.product_id from customer_order)

表1产品

1   cooker  500
2   Frying Pane 600
3   Spoon   110

表2 customerOrder

Name    product id
Sohaib      1   
Sohaib      2   
Ammar       2   
Max         2   

想要获取不在客户订单表中的商品<产品ID

执行上面提到的查询后我得到了

Product id
    2
    3
    1
    3
    1
    3
    1
    3

Answer 1

您可以使用not in或not exists：

select p.*
from products p
where not exists (select 1
                  from customerOrder co
                  where co.productid = p.id
                 );