delete from tb_user where true;
ALTER TABLE tb_user AUTO_INCREMENT = 1;
delete from tb_user_info where true;
delete from tb_user_major where true;
ALTER TABLE tb_user_major AUTO_INCREMENT = 1;
delete from tb_collage where true;
ALTER TABLE tb_collage AUTO_INCREMENT = 1;
delete from tb_major where true;
ALTER TABLE tb_major AUTO_INCREMENT = 1;
delete from tb_course where true;
ALTER TABLE tb_course AUTO_INCREMENT = 1;
delete from tb_course_course_time where true;
delete from tb_user_course_record where true;
ALTER TABLE tb_user_course_record AUTO_INCREMENT = 1;
delete from tb_course_teacher where true;