SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Identifier x
    Function plus (children 1)
     ExpressionList (children 2)
      Literal UInt64_1
      Function plus (children 1)
       ExpressionList (children 2)
        Literal UInt64_2
        Literal UInt64_3 (alias x)