思路：利用join
select rn.step as rnstep,rn.numbs as rnnumbs,rr.step as rrstep,rr.numbs as rrnumbs from route_num rn
inner join
route_num rr
思路：利用join
select rn.step as rnstep,rn.numbs as rnnumbs,rr.step as rrstep,rr.numbs as rrnumbs from route_num rn
inner join
route_num rr