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 materialize (children 1)
         ExpressionList (children 1)
          Function toFixedString (children 1)
           ExpressionList (children 2)
            Literal \'a\'
            Literal UInt64_1
        Function toFixedString (children 1)
         ExpressionList (children 2)
          Literal \'b\'
          Literal UInt64_1
        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