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1.上图两个表,要求找出掌握Skills中全部3个技能的员工,即神崎和相田,要求用mysql的语句实现
2.刚学sql,不是很会,想了好久
3.下面是书里面用sql server写的,我也不是很理解,另外mysql中没有except
SELECT DISTINCT emp
FROM EmpSkills ES1
WHERE NOT EXISTS
(SELECT skill
FROM Skills
EXCEPT
SELECT skill
FROM EmpSkills ES2
WHERE ES1.emp = ES2.emp);
对应的数据替换一下就可以了.