/magento/app/code/core/Mage/Log/sql/log_setup/mysql4-upgrade-0.7.3-0.7.4.php

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magentocommerce.com so we can send you a copy immediately.
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 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
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 *
 * @category    Mage
 * @package     Mage_Log
 * @copyright   Copyright (c) 2012 Magento Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */


$installer = $this;
/* @var $installer Mage_Core_Model_Resource_Setup */

$installer->startSetup();
$installer->getConnection()->addKey($installer->getTable('log/customer'), 'IDX_VISITOR', 'visitor_id');
$installer->getConnection()->addKey($installer->getTable('log/url_table'), 'PRIMARY', 'url_id', 'primary');
$installer->getConnection()->addKey($installer->getTable('log/url_table'), 'IDX_VISITOR', 'visitor_id');
$installer->endSetup();