select * from pn_tablename a join pn_tablename b;
odps不支持無 on 的 join 會報
*ODPS-0130252 Cartesian product is not allowed without map join *的錯誤
可以往select里增加字段來繞過這個限制
select * from (select *, 1 as raoguo from pn_tablename) a join (select *,1 as raoguo from pn_tablename) b on a.raoguo = b.raoguo;