Using the below query, I am able to retrieve the expected data but I was wondering if there is a better way to do this.

create table student_course(id number,student number,subject varchar2(30));

insert into student_course values(1,100,NULL);
insert into student_course values(2,100,'Science');
insert into student_course values(3,200,'Mathematics');
insert into student_course values(4,200,'Science');
insert into student_course values(5,300,'English');
insert into student_course values(6,400,NULL);
insert into student_course values(7,500,'Mathematics');
insert into student_course values(8,500,NULL);
insert into student_course values(9,600,'Science');

commit;

select * from student_course where student in (select student
from student_course
group by student
   having
   min(nvl(subject,'0'))='0' and count(distinct subject)>=1);