SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function CAST (children 1)
     ExpressionList (children 2)
      Function materialize (children 1)
       ExpressionList (children 1)
        Function CAST (children 1)
         ExpressionList (children 2)
          Literal UInt64_1
          Literal \'Nullable(Enum(\\\'A\\\' = 1, \\\'B\\\' = 2))\'
      Literal \'Nullable(String)\'
