SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function categoricalInformationValue (children 1)
     ExpressionList (children 2)
      Identifier c1
      Identifier c2
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Function VALUES (children 1)
       ExpressionList (children 1)
        Literal Tuple_(NULL, NULL)
