MySQL多於1行錯誤

Question

這是我輸入的內容，我必須用「NOT IN」替換EXCEPT。所以這解決了一個錯誤，但現在它返回多於一行。我不確定那是多麼糟糕。我剛剛開始弄清楚MySQL並嘗試從本書中獲取示例。

SELECT S.sname 
FROM suppliers S 
WHERE (
    (SELECT P.pid FROM parts P) NOT IN 
    (SELECT C.pid FROM catalog C WHERE C.sid = S.sid) 
); 

ERROR 1242 (21000): Subquery returns more than 1 row 

Answer 1

SELECT S.sname 
FROM suppliers S 
WHERE NOT EXISTS(
SELECT P.pid FROM parts P, catalog C 
WHERE P.pid = C.pid AND C.sid = S.sid) 
);