今天爱分享给大家带来DQL语言-多表查询【七】,希望能够帮助到大家。
内连接
隐式内连接:select * from emp e1, dept d1 where e1.deptno = d1.deptno;
显示内连接:select * from emp e1 inner join dept d1 on e1.deptno = d1.deptno;
外连接
左外连接
隐式左外连接:select * from emp e1,dept d1 where e1.deptno = d1.deptno(+);
显示左外连接:select * from emp e1 left outer join dept d1 on e1.deptno = d1.deptno;
右外连接
隐式右外连接:select * from emp e1,dept d1 where e1.deptno(+) = d1.deptno;
显示右外连接:select * from emp e1 right outer join dept d1 on e1.deptno = d1.deptno;
全外连接:select * from emp e1 full outer join dept d1 on e1.deptno = d1.deptno;
交叉连接
隐式交叉连接:select * from emp, dept;
显示交叉连接:select * from emp e1 cross join dept d1;
原文链接:https://itblood.website/128.html,转载请注明出处。

![学院理事长的职责 让濒临倒闭的男子学校复活!最强经营战略1.0[PC+安卓/1.05G] [日系RPG/AI汉化]](/wp-content/uploads/replace/2025/09/05/119512a7890540691707294a8bef5b99.webp)