SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Function concat (children 1)
       ExpressionList (children 3)
        Function toFixedString (children 1)
         ExpressionList (children 2)
          Literal \'a\'
          Literal UInt64_1
        Literal \'b\'
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal \'c\'
      Literal \'abc\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.numbers
   Literal UInt64_5