#!/usr/bin/perl -w

use strict;
use XML::Simple;
use Data::Dumper;

$/ = undef;
my $string = <DATA>;
my $ref = XMLin($string);
print Dumper $ref;

__DATA__

<config>
        <columnname>DATE extract</columnname> 
        <columnname>DATE_deleted</columnname>
        <columnname>DATE1</columnname> 
        <columnname>DATE2</columnname>
</config>