示例DEMO

https://www.ituring.com.cn/book/1880
https://download.ituring.com.cn/book/download/f8e8fcb6-84d8-4839-bd5a-3c737478ae11

7 集合运算

7-1 表的加减法

选取表的公共部分——INTERSECT

INTERSECT(交集)

SELECT product_id, product_name
FROM Product
INTERSECT
SELECT product_id, product_name
FROM Product2
ORDER BY product_id;

记录的减法——EXCEPT

EXCEPT(差集)

SELECT product_id, product_name
FROM Product
EXCEPT
SELECT product_id, product_name
FROM Product2
ORDER BY product_id;