system/database/drivers/mysql/mysql_driver.php
<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2019 - 2022, CodeIgniter Foundation
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* @package CodeIgniter
* @author EllisLab Dev Team
* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
* @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
* @copyright Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
* @license https://opensource.org/licenses/MIT MIT License
* @link https://codeigniter.com
* @since Version 1.0.0
* @filesource
*/
defined('BASEPATH') OR exit('No direct script access allowed');
/**
* MySQL 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 https://codeigniter.com/userguide3/database/
*/
class CI_DB_mysql_driver extends CI_DB {
/**
* Database driver
*
* @var string
*/
public $dbdriver = 'mysql';
/**
* Compression flag
*
* @var bool
*/
public $compress = FALSE;
/**
* DELETE hack flag
*
* Whether to use the MySQL "delete hack" which allows the number
* of affected rows to be shown. Uses a preg_replace when enabled,
* adding a bit more processing to all queries.
*
* @var bool
*/
public $delete_hack = TRUE;
/**
* Strict ON flag
*
* Whether we're running in strict SQL mode.
*
* @var bool
*/
public $stricton;
// --------------------------------------------------------------------
/**
* Identifier escape character
*
* @var string
*/
protected $_escape_char = '`';
// --------------------------------------------------------------------
/**
* Class constructor
*
* @param array $params
* @return void
*/
public function __construct($params)
{
parent::__construct($params);
if ( ! empty($this->port))
{
$this->hostname .= ':'.$this->port;
}
}
// --------------------------------------------------------------------
/**
* Non-persistent database connection
*
* @param bool $persistent
* @return resource
*/
public function db_connect($persistent = FALSE)
{
$client_flags = ($this->compress === FALSE) ? 0 : MYSQL_CLIENT_COMPRESS;
if ($this->encrypt === TRUE)
{
$client_flags = $client_flags | MYSQL_CLIENT_SSL;
}
// Error suppression is necessary mostly due to PHP 5.5+ issuing E_DEPRECATED messages
$this->conn_id = ($persistent === TRUE)
? mysql_pconnect($this->hostname, $this->username, $this->password, $client_flags)
: mysql_connect($this->hostname, $this->username, $this->password, TRUE, $client_flags);
// ----------------------------------------------------------------
// Select the DB... assuming a database name is specified in the config file
if ($this->database !== '' && ! $this->db_select())
{
log_message('error', 'Unable to select database: '.$this->database);
return ($this->db_debug === TRUE)
? $this->display_error('db_unable_to_select', $this->database)
: FALSE;
}
if (is_resource($this->conn_id))
{
if ( ! mysql_set_charset($this->char_set, $this->conn_id))
{
log_message('error', "Database: Unable to set the configured connection charset ('{$this->char_set}').");
$this->close();
return ($this->db->debug) ? $this->display_error('db_unable_to_set_charset', $this->char_set) : FALSE;
}
if (isset($this->stricton))
{
if ($this->stricton)
{
$this->simple_query('SET SESSION sql_mode = CONCAT(@@sql_mode, ",", "STRICT_ALL_TABLES")');
}
else
{
$this->simple_query(
'SET SESSION sql_mode =
REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(
@@sql_mode,
"STRICT_ALL_TABLES,", ""),
",STRICT_ALL_TABLES", ""),
"STRICT_ALL_TABLES", ""),
"STRICT_TRANS_TABLES,", ""),
",STRICT_TRANS_TABLES", ""),
"STRICT_TRANS_TABLES", "")'
);
}
}
return $this->conn_id;
}
return FALSE;
}
// --------------------------------------------------------------------
/**
* Reconnect
*
* Keep / reestablish the db connection if no queries have been
* sent for a length of time exceeding the server's idle timeout
*
* @return void
*/
public function reconnect()
{
if (mysql_ping($this->conn_id) === FALSE)
{
$this->conn_id = FALSE;
}
}
// --------------------------------------------------------------------
/**
* Select the database
*
* @param string $database
* @return bool
*/
public function db_select($database = '')
{
if ($database === '')
{
$database = $this->database;
}
if (mysql_select_db($database, $this->conn_id))
{
$this->database = $database;
$this->data_cache = array();
return TRUE;
}
return FALSE;
}
// --------------------------------------------------------------------
/**
* Database version number
*
* @return string
*/
public function version()
{
if (isset($this->data_cache['version']))
{
return $this->data_cache['version'];
}
if ( ! $this->conn_id OR ($version = mysql_get_server_info($this->conn_id)) === FALSE)
{
return FALSE;
}
return $this->data_cache['version'] = $version;
}
// --------------------------------------------------------------------
/**
* Execute the query
*
* @param string $sql an SQL query
* @return mixed
*/
protected function _execute($sql)
{
return mysql_query($this->_prep_query($sql), $this->conn_id);
}
// --------------------------------------------------------------------
/**
* Prep the query
*
* If needed, each database adapter can prep the query string
*
* @param string $sql an SQL query
* @return string
*/
protected function _prep_query($sql)
{
// mysql_affected_rows() returns 0 for "DELETE FROM TABLE" queries. This hack
// modifies the query so that it a proper number of affected rows is returned.
if ($this->delete_hack === TRUE && preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $sql))
{
return trim($sql).' WHERE 1=1';
}
return $sql;
}
// --------------------------------------------------------------------
/**
* Begin Transaction
*
* @return bool
*/
protected function _trans_begin()
{
$this->simple_query('SET AUTOCOMMIT=0');
return $this->simple_query('START TRANSACTION'); // can also be BEGIN or BEGIN WORK
}
// --------------------------------------------------------------------
/**
* Commit Transaction
*
* @return bool
*/
protected function _trans_commit()
{
if ($this->simple_query('COMMIT'))
{
$this->simple_query('SET AUTOCOMMIT=1');
return TRUE;
}
return FALSE;
}
// --------------------------------------------------------------------
/**
* Rollback Transaction
*
* @return bool
*/
protected function _trans_rollback()
{
if ($this->simple_query('ROLLBACK'))
{
$this->simple_query('SET AUTOCOMMIT=1');
return TRUE;
}
return FALSE;
}
// --------------------------------------------------------------------
/**
* Platform-dependent string escape
*
* @param string
* @return string
*/
protected function _escape_str($str)
{
return mysql_real_escape_string($str, $this->conn_id);
}
// --------------------------------------------------------------------
/**
* Affected Rows
*
* @return int
*/
public function affected_rows()
{
return mysql_affected_rows($this->conn_id);
}
// --------------------------------------------------------------------
/**
* Insert ID
*
* @return int
*/
public function insert_id()
{
return mysql_insert_id($this->conn_id);
}
// --------------------------------------------------------------------
/**
* List table query
*
* Generates a platform-specific query string so that the table names can be fetched
*
* @param bool $prefix_limit
* @return string
*/
protected function _list_tables($prefix_limit = FALSE)
{
$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
if ($prefix_limit !== FALSE && $this->dbprefix !== '')
{
return $sql." LIKE '".$this->escape_like_str($this->dbprefix)."%'";
}
return $sql;
}
// --------------------------------------------------------------------
/**
* Show column query
*
* Generates a platform-specific query string so that the column names can be fetched
*
* @param string $table
* @return string
*/
protected function _list_columns($table = '')
{
return 'SHOW COLUMNS FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE);
}
// --------------------------------------------------------------------
/**
* Returns an object with field data
*
* @param string $table
* @return array
*/
public function field_data($table)
{
if (($query = $this->query('SHOW COLUMNS FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE))) === FALSE)
{
return FALSE;
}
$query = $query->result_object();
$retval = array();
for ($i = 0, $c = count($query); $i < $c; $i++)
{
$retval[$i] = new stdClass();
$retval[$i]->name = $query[$i]->Field;
sscanf($query[$i]->Type, '%[a-z](%d)',
$retval[$i]->type,
$retval[$i]->max_length
);
$retval[$i]->default = $query[$i]->Default;
$retval[$i]->primary_key = (int) ($query[$i]->Key === 'PRI');
}
return $retval;
}
// --------------------------------------------------------------------
/**
* Error
*
* Returns an array containing code and message of the last
* database error that has occurred.
*
* @return array
*/
public function error()
{
return array('code' => mysql_errno($this->conn_id), 'message' => mysql_error($this->conn_id));
}
// --------------------------------------------------------------------
/**
* FROM tables
*
* Groups tables in FROM clauses if needed, so there is no confusion
* about operator precedence.
*
* @return string
*/
protected function _from_tables()
{
if ( ! empty($this->qb_join) && count($this->qb_from) > 1)
{
return '('.implode(', ', $this->qb_from).')';
}
return implode(', ', $this->qb_from);
}
// --------------------------------------------------------------------
/**
* Close DB Connection
*
* @return void
*/
protected function _close()
{
// Error suppression to avoid annoying E_WARNINGs in cases
// where the connection has already been closed for some reason.
@mysql_close($this->conn_id);
}
}