
3Q!
------解决思路----------------------
select * from A2
except
select * from A1
------解决思路----------------------
SELECT A2.*
FROM A2
LEFT JOIN A1
ON A2.颜色 = A1.颜色 AND A2.样式 = A1.样式
WHERE A1.颜色 IS NULL AND A1.样式 IS NULL
SELECT A2.*
FROM A2
LEFT JOIN A1
ON A2.颜色 = A1.颜色 AND A2.样式 = A1.样式
WHERE A1.颜色 IS NULL AND A1.样式 IS NULL