SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function extractGroups (children 1)
     ExpressionList (children 2)
      Function materialize (children 1)
       ExpressionList (children 1)
        Function CAST (children 1)
         ExpressionList (children 2)
          Literal \'hello world\'
          Literal \'FixedString(12)\'
      Function CAST (children 1)
       ExpressionList (children 2)
        Literal \'(\\\\w+) (\\\\w+)\'
        Literal \'FixedString(11)\'
