SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function mapFromArrays (children 1)
     ExpressionList (children 2)
      Literal Array_[\'aa\', \'bb\']
      Function materialize (children 1)
       ExpressionList (children 1)
        Function map (children 1)
         ExpressionList (children 4)
          Literal \'a\'
          Literal UInt64_4
          Literal \'b\'
          Literal UInt64_5
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Function numbers (children 1)
       ExpressionList (children 1)
        Literal UInt64_2