@Jess thanks for your enthusiastic and valuable hint ,I have solved it. On Sat, Mar 18, 2017 at 8:08 AM, Jess Balint <[email protected]> wrote:
> Try RelMetadataQuery.getColumnOrigin() > > Jess > > On Fri, Mar 17, 2017 at 3:07 AM, weijie tong <[email protected]> > wrote: > > > I have a requirement to find the on condition name of a join clause, > > but while the condition columns from two tables are the same ,I can not > > find the exact join column name. > > For example : select col1 , col2 from table1 a join table2 b on > a.colo > > = b.colo . When I apply a rule using HepPlanner, I want to find the > > condition names from both tables ,i.e. : colo and another colo , using > the > > codes : joinRel.getRowType().getFieldList().get(index).getName() ,the > > index > > parameter was got from the condition method,the joinRel was the matched > > join RelNode. The reust is : colo and colo0 . As you see , the second > joint > > key has a zero postfix. > > I want to know how to find the correct joint column names at this case? > > >
