SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Identifier my_field
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 2)
           Asterisk
           Literal \'redefined\' (alias my_field)
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Subquery (children 1)
              SelectWithUnionQuery (children 1)
               ExpressionList (children 1)
                SelectQuery (children 2)
                 ExpressionList (children 1)
                  Asterisk
                 TablesInSelectQuery (children 1)
                  TablesInSelectQueryElement (children 1)
                   TableExpression (children 1)
                    TableIdentifier test_subquery
