删除路线站点关系 

DELETE FROM tb_station_info_draw WHERE id in (SELECT stationId FROM tb_road_station_relation_draw WHERE cityId=283 AND roadId=46);

DELETE FROM tb_road_station_relation_draw WHERE cityId=283 AND roadId=46;

由于sql分开，要先执行1，再执行2。 

 

删除路线点

DELETE FROM tb_road_point_draw WHERE cityId=285 AND roadId=21;