SQL Joins
Posted: Sat Dec 18, 2021 6:45 am
select * from emp;
select * from dept;
select e.* from emp e
inner join dept d on e.deptno = d.deptno
select e.* from emp e
left join dept d on e.deptno = d.deptno
select e.* from emp e
left outer join dept d on e.deptno = d.deptno
select e.* from emp e
right join dept d on e.deptno = d.deptno
select e.* from emp e
right outer join dept d on e.deptno = d.deptno
-- Self Join
select a.empno, a.ename, a.job, b.ename Manager from emp a
left join emp b on a.mgr = b.empno
order by a.mgr;
select * from dept;
select e.* from emp e
inner join dept d on e.deptno = d.deptno
select e.* from emp e
left join dept d on e.deptno = d.deptno
select e.* from emp e
left outer join dept d on e.deptno = d.deptno
select e.* from emp e
right join dept d on e.deptno = d.deptno
select e.* from emp e
right outer join dept d on e.deptno = d.deptno
-- Self Join
select a.empno, a.ename, a.job, b.ename Manager from emp a
left join emp b on a.mgr = b.empno
order by a.mgr;