Log Clearing Script Magento

<?php
$xml = simplexml_load_file('./app/etc/local.xml', NULL, LIBXML_NOCDATA);

$db['host'] = $xml->global->resources->default_setup->connection->host;
$db['name'] = $xml->global->resources->default_setup->connection->dbname;
$db['user'] = $xml->global->resources->default_setup->connection->username;
$db['pass'] = $xml->global->resources->default_setup->connection->password;
$db['pref'] = $xml->global->resources->db->table_prefix;

if($_GET['clean'] == 'log') clean_log_tables();
if($_GET['clean'] == 'var') clean_var_directory();

function clean_log_tables() {
 global $db;
 
 $tables = array(
  'dataflow_batch_export',
  'dataflow_batch_import',
  'log_customer',
  'log_quote',
  'log_summary',
  'log_summary_type',
  'log_url',
  'log_url_info',
  'log_visitor',
  'log_visitor_info',
  'log_visitor_online',
  'index_event',
  'report_event',
  'report_compared_product_index',
  'report_viewed_product_index',
  'catalog_compare_item',
  'catalogindex_aggregation',
  'catalogindex_aggregation_tag',
  'catalogindex_aggregation_to_tag'
 );
 
 mysql_connect($db['host'], $db['user'], $db['pass']) or die(mysql_error());
 mysql_select_db($db['name']) or die(mysql_error());
 
 foreach($tables as $v => $k) {
  @mysql_query('TRUNCATE `'.$db['pref'].$k.'`');
 }
}

function clean_var_directory() {
 $dirs = array(
  'downloader/.cache/*',
  'downloader/pearlib/cache/*',
  'downloader/pearlib/download/*',
  'var/cache/',
  'var/locks/',
  'var/log/',
  'var/report/',
  'var/session/',
  'var/tmp/'
 );
 
 foreach($dirs as $v => $k) {
  exec('rm -rf '.$k);
 }
}