select * from emp,dep;
select * from emp,dep where emp.dep_id = dep.id;
select * from emp,dep where emp.dep_id = dep.id and dep.name = "技术";select * from emp inner join dep on emp.dep_id = dep.id;
select * from emp inner join dep on emp.dep_id = dep.id
where dep.name = "技术";
inner join 连接两个表, where过滤条件,只取条件符合的select * from emp left join dep on emp.dep_id = dep.id;select * from emp right join dep on emp.dep_id = dep.id;select * from emp left join dep on emp.dep_id = dep.id
union
select * from emp right join dep on emp.dep_id = dep.id;免责声明：本站发布的内容（图片、视频和文字）以原创、转载和分享为主，文章观点不代表本网站立场，如果涉及侵权请联系站长邮箱：is@yisu.com进行举报，并提供相关证据，一经查实，将立刻删除涉嫌侵权内容。
