php - SQL 查询运算符减号不起作用

Question

(SELECT IDOperatore FROM operatore) MINUS 
(SELECT IDOperatore FROM commessaoperatore GROUP BY IDOperatore)  

此查询无效，即使我尝试将 MINUS 替换为 EXCEPT。 单一查询 SELECT IDOperatore FROM operatore 和 SELECT IDOperatore FROM commessaoperatore GROUP BY IDOperatore 正在运行，但如果我尝试将它们与 Minus 运算符放在一起不工作。

ERROR: #1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'MINUS (SELECT IDOperatore FROM commessaoperatore GROUP BY IDOperatore)' at line 1

Answer 1

MINUS在mysql中不存在

但是对于您的查询，您可以使用 NOT EXISTS:

SELECT IDOperatore FROM operatore o
WHERE NOT EXISTS (SELECT 1
                 FROM commessaoperatore c 
                 WHERE c.IDOperatore = o.IDOperatore)