SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function equals (children 1)
     ExpressionList (children 2)
      Function tryBase64Decode (children 1)
       ExpressionList (children 1)
        Function base64Encode (children 1)
         ExpressionList (children 1)
          Literal \'foo\'
      Literal \'foo\'
    Function equals (children 1)
     ExpressionList (children 2)
      Function base64Encode (children 1)
       ExpressionList (children 1)
        Function tryBase64Decode (children 1)
         ExpressionList (children 1)
          Literal \'Zm9v\'
      Literal \'Zm9v\'