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?
