List the id of students who attended  statistics courses in the order of attendance date.
create table student_course_attendance (student_id varchar, course_id varchar, date_of_attendance varchar, PRIMARY KEY (student_id)); create table courses (course_id varchar, course_name varchar, PRIMARY KEY (course_id))
select t2.student_id from courses as t1 join student_course_attendance as t2 on t1.course_id = t2.course_id where t1.course_name = "statistics" order by t2.date_of_attendance