SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function materialize (alias x) (children 1)
     ExpressionList (children 1)
      Function toFixedString (children 1)
       ExpressionList (children 2)
        Literal \'\'
        Literal UInt64_2
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.one
   ExpressionList (children 1)
    Identifier x
