select e.ename
                        from emp1 e, implemp1 ie
                        where e.empno=ie.empno
                        group by e.ename, e.deptno
                        having count(ie.IMPL) > any(select count(iee.impl)
                                                   from emp1 ee, implemp1 iee
                                                   where ee.empno=iee.empno
                                                   and ee.deptno=30
                                                   group by ee.ename);