字段修改update my_courses set course_featured4 where course_featured3update my_courses set cours
字段修改
update my_courses set course_featured=4 where course_featured=3;
update my_courses set course_featured=3 where course_featured=2;
字段修改
update my_courses set course_featured=4 where course_featured=3;
update my_courses set course_featured=3 where course_featured=2;