SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function extractGroups (children 1)
     ExpressionList (children 2)
      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)\'