mysql中只返回不同的？

Question

select sum(price) 
from product 
where id in (select productid 
      from orders where status!=0 
      and userid=1) 

如果我的返回的productid =（1,2,2）

總和將只能是1之和2代替1,2-總和，AND2

我試圖

select sum(price) from product where id in (1,2,2) 

同樣的結果，我如何得到模糊的總和？

Answer 1

SELECT SUM(p.price) 
FROM product AS p 
    LEFT JOIN orders AS o 
     ON p.id = o.productid 
WHERE o.productid IS NOT NULL 
    AND o.status <> 0 
    AND o.userid = 1