查询出人数最多的那个部门的部门编号和部门名称
--查询出人数最多的那个部门的部门编号和部门名称
select e.deptno, d.dname, count(1)
  from (select cout
  from (select count(1) cout
  from emp e
  group by e.deptno
  order by 1 desc) 
  where rownum = 1) t,
  emp e,
  dept d
 where e.deptno = d.deptno
 group by e.deptno, d.dname
 having count(1) = t.cout

最后一行报错,把t.cout换成任意的数字就可以了,不明白,在线等

------解决方案--------------------

SQL code

select deptno,dname,cou from 
(select dept.deptno,min(dept.dname) dname,count(emp.empno) cou
from dept left join emp on dept.deptno=emp.deptno
group by dept.deptno order by cou desc) t
where rownum=1;