[CALCITE-2382] Column not found when sub-query joins lateral table function

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.16.0
• Fix Version/s: 1.17.0
• Component/s: core
• Assignee: Julian Hyde
• Reporter: pengzhiwei
• Created: 26/Jun/18 11:08
• Updated: 20/Jul/18 08:18
• Resolved: 29/Jun/18 18:47

Description

1. When using subquery join lateral table function as followed:

 

 select * from ( select 5 as f0 from s.t ) a,lateral table(s.GenerateStrings(f0)) as t(n, c)  where char_length(c) > 3

'SqlValidatorException: Column 'F0' not found in any table'  was thrown out.

I find the reason is that  SqlValidatorImpl add the namespace of Identifier 's.t'  to the children of tableScope,but not the subquey's namespace,just as the code show bellow in  SqlValidatorImpl#registerFrom:

case IDENTIFIER:
  ...........
  if (tableScope == null) {
  tableScope = new TableScope(parentScope, node);
  }
 tableScope.addChild(newNs, alias, forceNullable);

I think the namespace of  JoinScope's left child should be  the children of tableScope which was referenced by the table function,just as the code show bellow in  SqlValidatorImpl#registerFrom:

case COLLECTION_TABLE:
  ....
  TableScope tableScope = null;

  if(parentScope instanceof JoinScope) {

  tableScope = new TableScope(new EmptyScope(this),operand);
  JoinScope scope = (JoinScope) parentScope;

  SqlValidatorNamespace leftNs = scope.getChildren().get(0);

  tableScope.addChild(leftNs,scope.children.get(0).name,forceNullable);
}
....

After this modification,the case upon runs well.

Is there any problem for this modification? Any suggestions is welcomed.Thanks a lot.