oracle数据库sql语句06 join

--group by
select deptno,count(*) from emp group by deptno;








--group by ... having
select deptno, count(*) from emp group by deptno having count(*)>=5;








--join
select * from emp join dept on emp.deptno = dept.deptno;








--join right
select * from emp right join dept on emp.deptno = dept.deptno;