system/database/drivers/pdo/pdo_driver.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.2.4 or newer
 *
 * NOTICE OF LICENSE
 *
 * Licensed under the Open Software License version 3.0
 *
 * This source file is subject to the Open Software License (OSL 3.0) that is
 * bundled with this package in the files license.txt / license.rst.  It is
 * also available through the world wide web at this URL:
 * http://opensource.org/licenses/OSL-3.0
 * 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
 * licensing@ellislab.com so we can send you a copy immediately.
 *
 * @package		CodeIgniter
 * @author		EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
 * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
 * @link		http://codeigniter.com
 * @since		Version 2.1.0
 * @filesource
 */

/**
 * PDO Database Adapter Class
 *
 * Note: _DB is an extender class that the app controller
 * creates dynamically based on whether the query builder
 * class is being used or not.
 *
 * @package		CodeIgniter
 * @subpackage	Drivers
 * @category	Database
 * @author		EllisLab Dev Team
 * @link		http://codeigniter.com/user_guide/database/
 */
class CI_DB_pdo_driver extends CI_DB {

	public $dbdriver = 'pdo';

	// The character used to escaping
	protected $_escape_char = '"';

	// clause and character used for LIKE escape sequences
	protected $_like_escape_str = " ESCAPE '%s' ";
	protected $_like_escape_chr = '!';

	/**
	 * The syntax to count rows is slightly different across different
	 * database engines, so this string appears in each driver and is
	 * used for the count_all() and count_all_results() functions.
	 */
	protected $_count_string = 'SELECT COUNT(*) AS ';
	protected $_random_keyword;

	protected $trans_enabled = FALSE;

	// need to track the PDO options
	public $options = array();

	/**
	 * Constructor
	 *
	 * Validates the DSN string and/or detects the subdriver
	 *
	 * @param	array
	 * @return	void
	 */
	public function __construct($params)
	{
		parent::__construct($params);

		if (preg_match('/([^;]+):/', $this->dsn, $match) && count($match) === 2)
		{
			// If there is a minimum valid dsn string pattern found, we're done
			// This is for general PDO users, who tend to have a full DSN string.
			$this->subdriver = $match[1];
			return;
		}
		// Legacy support for DSN specified in the hostname field
		elseif (preg_match('/([^;]+):/', $this->hostname, $match) && count($match) === 2)
		{
			$this->dsn = $this->hostname;
			$this->hostname = NULL;
			$this->subdriver = $match[1];
			return;
		}
		elseif (in_array($this->subdriver, array('mssql', 'sybase'), TRUE))
		{
			$this->subdriver = 'dblib';
		}
		elseif ($this->subdriver === '4D')
		{
			$this->subdriver = '4d';
		}
		elseif ( ! in_array($this->subdriver, array('4d', 'cubrid', 'dblib', 'firebird', 'ibm', 'informix', 'mysql', 'oci', 'odbc', 'sqlite', 'sqlsrv'), TRUE))
		{
			log_message('error', 'PDO: Invalid or non-existent subdriver');

			if ($this->db_debug)
			{
				show_error('Invalid or non-existent PDO subdriver');
			}

			throw new Exception('Invalid or non-existent PDO subdriver');
		}

		$this->dsn = NULL;
	}

	// --------------------------------------------------------------------

	/**
	 * Non-persistent database connection
	 *
	 * @param	bool
	 * @return	object
	 */
	public function db_connect($persistent = FALSE)
	{
		$this->options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_SILENT;
		$this->options[PDO::ATTR_PERSISTENT] = $persistent;

		// Connecting...
		try
		{
			return new PDO($this->dsn, $this->username, $this->password, $this->options);
		}
		catch (PDOException $e)
		{
			if ($this->db_debug && empty($this->failover))
			{
				$this->display_error($e->getMessage(), '', TRUE);
			}

			return FALSE;
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Persistent database connection
	 *
	 * @return	object
	 */
	public function db_pconnect()
	{
		return $this->db_connect(TRUE);
	}

	// --------------------------------------------------------------------

	/**
	 * Database version number
	 *
	 * @return	string
	 */
	public function version()
	{
		return isset($this->data_cache['version'])
			? $this->data_cache['version']
			: $this->data_cache['version'] = $this->conn_id->getAttribute(PDO::ATTR_SERVER_VERSION);
	}

	// --------------------------------------------------------------------

	/**
	 * Execute the query
	 *
	 * @param	string	an SQL query
	 * @return	mixed
	 */
	protected function _execute($sql)
	{
		return $this->conn_id->query($sql);
	}

	// --------------------------------------------------------------------

	/**
	 * Begin Transaction
	 *
	 * @return	bool
	 */
	public function trans_begin($test_mode = FALSE)
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
		{
			return TRUE;
		}

		// Reset the transaction failure flag.
		// If the $test_mode flag is set to TRUE transactions will be rolled back
		// even if the queries produce a successful result.
		$this->_trans_failure = ($test_mode === TRUE);

		return $this->conn_id->beginTransaction();
	}

	// --------------------------------------------------------------------

	/**
	 * Commit Transaction
	 *
	 * @return	bool
	 */
	public function trans_commit()
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
		{
			return TRUE;
		}

		return $this->conn_id->commit();
	}

	// --------------------------------------------------------------------

	/**
	 * Rollback Transaction
	 *
	 * @return	bool
	 */
	public function trans_rollback()
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
		{
			return TRUE;
		}

		return $this->conn_id->rollBack();
	}

	// --------------------------------------------------------------------

	/**
	 * Escape String
	 *
	 * @param	string
	 * @param	bool	whether or not the string will be used in a LIKE condition
	 * @return	string
	 */
	public function escape_str($str, $like = FALSE)
	{
		if (is_array($str))
		{
			foreach ($str as $key => $val)
			{
				$str[$key] = $this->escape_str($val, $like);
			}

			return $str;
		}

		// Escape the string
		$str = $this->conn_id->quote($str);

		// If there are duplicated quotes, trim them away
		if ($str[0] === "'")
		{
			$str = substr($str, 1, -1);
		}

		// escape LIKE condition wildcards
		if ($like === TRUE)
		{
			return str_replace(array($this->_like_escape_chr, '%', '_'),
						array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
						$str);
		}

		return $str;
	}

	// --------------------------------------------------------------------

	/**
	 * Affected Rows
	 *
	 * @return	int
	 */
	public function affected_rows()
	{
		return is_object($this->result_id) ? $this->result_id->rowCount() : 0;
	}

	// --------------------------------------------------------------------

	/**
	 * Insert ID
	 *
	 * @param	string
	 * @return	int
	 */
	public function insert_id($name = NULL)
	{
		return $this->conn_id->lastInsertId($name);
	}

	// --------------------------------------------------------------------

	/**
	 * Field data query
	 *
	 * Generates a platform-specific query so that the column data can be retrieved
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _field_data($table)
	{
		return 'SELECT TOP 1 * FROM '.$this->protect_identifiers($table);
	}

	// --------------------------------------------------------------------

	/**
	 * Error
	 *
	 * Returns an array containing code and message of the last
	 * database error that has occured.
	 *
	 * @return	array
	 */
	public function error()
	{
		$error = array('code' => '00000', 'message' => '');
		$pdo_error = $this->conn_id->errorInfo();

		if (empty($pdo_error[0]))
		{
			return $error;
		}

		$error['code'] = isset($pdo_error[1]) ? $pdo_error[0].'/'.$pdo_error[1] : $pdo_error[0];
		if (isset($pdo_error[2]))
		{
			 $error['message'] = $pdo_error[2];
		}

		return $error;
	}

	// --------------------------------------------------------------------

	/**
	 * Update_Batch statement
	 *
	 * Generates a platform-specific batch update string from the supplied data
	 *
	 * @param	string	the table name
	 * @param	array	the update data
	 * @param	array	the where clause
	 * @return	string
	 */
	protected function _update_batch($table, $values, $index, $where = NULL)
	{
		$ids = array();
		$where = ($where !== '' && count($where) >=1) ? implode(" ", $where).' AND ' : '';

		foreach ($values as $key => $val)
		{
			$ids[] = $val[$index];

			foreach (array_keys($val) as $field)
			{
				if ($field !== $index)
				{
					$final[$field][] =  'WHEN '.$index.' = '.$val[$index].' THEN '.$val[$field];
				}
			}
		}

		$sql   = 'UPDATE '.$table.' SET ';
		$cases = '';

		foreach ($final as $k => $v)
		{
			$cases .= $k.' = CASE '."\n";

			foreach ($v as $row)
			{
				$cases .= $row."\n";
			}

			$cases .= 'ELSE '.$k.' END, ';
		}

		$sql .= substr($cases, 0, -2);
		$sql .= ' WHERE '.$where.$index.' IN ('.implode(',', $ids).')';

		return $sql;
	}

	// --------------------------------------------------------------------

	/**
	 * Truncate statement
	 *
	 * Generates a platform-specific truncate string from the supplied data
	 *
	 * If the database does not support the truncate() command,
	 * then this method maps to 'DELETE FROM table'
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _truncate($table)
	{
		return 'TRUNCATE TABLE '.$table;
	}

}

/* End of file pdo_driver.php */
/* Location: ./system/database/drivers/pdo/pdo_driver.php */