db.php

<?php
/**
 * ownCloud
 *
 * @author Frank Karlitschek
 * @copyright 2012 Frank Karlitschek frank@owncloud.org
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

class DatabaseException extends Exception{
	private $query;

	public function __construct($message, $query){
		parent::__construct($message);
		$this->query = $query;
	}

	public function getQuery(){
		return $this->query;
	}
}

/**
 * This class manages the access to the database. It basically is a wrapper for
 * MDB2 with some adaptions.
 */
class OC_DB {
	const BACKEND_PDO=0;
	const BACKEND_MDB2=1;

	/**
	 * @var MDB2_Driver_Common
	 */
	static private $connection; //the prefered connection to use, either PDO or MDB2
	static private $backend=null;
	/**
	 * @var MDB2_Driver_Common
	 */
	static private $MDB2=null;
	/**
	 * @var PDO
	 */
	static private $PDO=null;
	/**
	 * @var MDB2_Schema
	 */
	static private $schema=null;
	static private $inTransaction=false;
	static private $prefix=null;
	static private $type=null;

	/**
	 * check which backend we should use
	 * @return int BACKEND_MDB2 or BACKEND_PDO
	 */
	private static function getDBBackend() {
		//check if we can use PDO, else use MDB2 (installation always needs to be done my mdb2)