select id, cmt_id, class_id from rt_class_meeting_class
insert into rt_class_meeting_class
cmt_id,class_id,#{cmtId},#{classId},
update rt_class_meeting_class
cmt_id = #{cmtId},class_id = #{classId},
where id = #{id}
delete from rt_class_meeting_class where id = #{id}
delete from rt_class_meeting_class where id in
#{id}