query: SELECT count(*) FROM Students WHERE student_id NOT IN (SELECT student_id FROM Student_Course_Enrolment)
question: It is any course enrollment that how many students not had?
query_toks: SELECT count ( * ) FROM Students WHERE student_id NOT IN ( SELECT student_id FROM Student_Course_Enrolment )
query_toks_no_value: select count ( * ) from students where student_id not in ( select student_id from student_course_enrolment )
question_toks: It is any course enrollment that how many students not had?