Merge CodeIgniter 3 support

author: Florian Pritz <bluewind@xinu.at> 2017-09-26 13:46:14 +0200
committer: Florian Pritz <bluewind@xinu.at> 2017-09-26 13:46:14 +0200
commit: 3ff6ffa3341c876b741feb66552cdd110b67872e (patch)
tree: 69e11cd0009ddd1346f2dc4cd8c47244368db28e /system/database/drivers/pdo
parent: bc2f7f596f727e204e8b8c5b849545745b3cbfaa (diff)
parent: 81a4c8c630ef59cffea0c24e64fb6fa7f09bfcf6 (diff)
30 files changed, 6047 insertions, 1015 deletions
diff --git a/system/database/drivers/pdo/index.html b/system/database/drivers/pdo/index.html
index c942a79ce..b702fbc39 100644
--- a/system/database/drivers/pdo/index.html
+++ b/system/database/drivers/pdo/index.html
@@ -1,3 +1,4 @@
+<!DOCTYPE html>
 <html>
 <head>
 	<title>403 Forbidden</title>
@@ -7,4 +8,4 @@
 <p>Directory access is forbidden.</p>
 
 </body>
-</html>
-\ No newline at end of file
+</html>
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index e0e7dab65..6afc999c2 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -1,811 +1,329 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php
 /**
  * CodeIgniter
  *
- * An open source application development framework for PHP 5.1.6 or newer
+ * An open source application development framework for PHP
  *
- * @package		CodeIgniter
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
- * @author		EllisLab Dev Team
- * @link		http://codeigniter.com
- * @since		Version 2.1.2
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 2.1.0
  * @filesource
  */
-
-// ------------------------------------------------------------------------
+defined('BASEPATH') OR exit('No direct script access allowed');
 
 /**
  * PDO Database Adapter Class
  *
  * Note: _DB is an extender class that the app controller
- * creates dynamically based on whether the active record
+ * 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/
+ * @link		https://codeigniter.com/user_guide/database/
  */
 class CI_DB_pdo_driver extends CI_DB {
 
-	var $dbdriver = 'pdo';
-
-	// the character used to excape - not necessary for PDO
-	var $_escape_char = '';
-	var $_like_escape_str;
-	var $_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.
-	 */
-	var $_count_string = "SELECT COUNT(*) AS ";
-	var $_random_keyword;
-
-	var $options = array();
-
-	function __construct($params)
-	{
-		parent::__construct($params);
-
-		// clause and character used for LIKE escape sequences
-		if (strpos($this->hostname, 'mysql') !== FALSE)
-		{
-			$this->_like_escape_str = '';
-			$this->_like_escape_chr = '';
-
-			//Prior to this version, the charset can't be set in the dsn
-			if(is_php('5.3.6'))
-			{
-				$this->hostname .= ";charset={$this->char_set}";
-			}
-
-			//Set the charset with the connection options
-			$this->options['PDO::MYSQL_ATTR_INIT_COMMAND'] = "SET NAMES {$this->char_set}";
-		}
-		elseif (strpos($this->hostname, 'odbc') !== FALSE)
-		{
-			$this->_like_escape_str = " {escape '%s'} ";
-			$this->_like_escape_chr = '!';
-		}
-		else
-		{
-			$this->_like_escape_str = " ESCAPE '%s' ";
-			$this->_like_escape_chr = '!';
-		}
-
-		empty($this->database) OR $this->hostname .= ';dbname='.$this->database;
-
-		$this->trans_enabled = FALSE;
-
-		$this->_random_keyword = ' RND('.time().')'; // database specific random keyword
-	}
-
 	/**
-	 * Non-persistent database connection
+	 * Database driver
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @var	string
 	 */
-	function db_connect()
-	{
-		$this->options['PDO::ATTR_ERRMODE'] = PDO::ERRMODE_SILENT;
-
-		return new PDO($this->hostname, $this->username, $this->password, $this->options);
-	}
-
-	// --------------------------------------------------------------------
+	public $dbdriver = 'pdo';
 
 	/**
-	 * Persistent database connection
+	 * PDO Options
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @var	array
 	 */
-	function db_pconnect()
-	{
-		$this->options['PDO::ATTR_ERRMODE'] = PDO::ERRMODE_SILENT;
-		$this->options['PDO::ATTR_PERSISTENT'] = TRUE;
-	
-		return new PDO($this->hostname, $this->username, $this->password, $this->options);
-	}
+	public $options = array();
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Reconnect
+	 * Class constructor
 	 *
-	 * Keep / reestablish the db connection if no queries have been
-	 * sent for a length of time exceeding the server's idle timeout
+	 * Validates the DSN string and/or detects the subdriver.
 	 *
-	 * @access	public
+	 * @param	array	$params
 	 * @return	void
 	 */
-	function reconnect()
-	{
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Select the database
-	 *
-	 * @access	private called by the base class
-	 * @return	resource
-	 */
-	function db_select()
-	{
-		// Not needed for PDO
-		return TRUE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Set client character set
-	 *
-	 * @access	public
-	 * @param	string
-	 * @param	string
-	 * @return	resource
-	 */
-	function db_set_charset($charset, $collation)
-	{
-		// @todo - add support if needed
-		return TRUE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Version number query string
-	 *
-	 * @access	public
-	 * @return	string
-	 */
-	function _version()
-	{
-		return $this->conn_id->getAttribute(PDO::ATTR_CLIENT_VERSION);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Execute the query
-	 *
-	 * @access	private called by the base class
-	 * @param	string	an SQL query
-	 * @return	object
-	 */
-	function _execute($sql)
+	public function __construct($params)
 	{
-		$sql = $this->_prep_query($sql);
-		$result_id = $this->conn_id->prepare($sql);
+		parent::__construct($params);
 
-		if (is_object($result_id) && ($result = $result_id->execute()))
+		if (preg_match('/([^:]+):/', $this->dsn, $match) && count($match) === 2)
 		{
-			if (is_numeric(stripos($sql, 'SELECT')))
-			{
-				$this->affect_rows = count($result_id->fetchAll());
-			}
-			else
-			{
-				$this->affect_rows = $result_id->rowCount();
-			}
+			// 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;
 		}
-		else
+		// Legacy support for DSN specified in the hostname field
+		elseif (preg_match('/([^:]+):/', $this->hostname, $match) && count($match) === 2)
 		{
-			$this->affect_rows = 0;
-			$result = FALSE;
+			$this->dsn = $this->hostname;
+			$this->hostname = NULL;
+			$this->subdriver = $match[1];
+			return;
 		}
-
-		return $result;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Prep the query
-	 *
-	 * If needed, each database adapter can prep the query string
-	 *
-	 * @access	private called by execute()
-	 * @param	string	an SQL query
-	 * @return	string
-	 */
-	function _prep_query($sql)
-	{
-		return $sql;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Begin Transaction
-	 *
-	 * @access	public
-	 * @return	bool
-	 */
-	function trans_begin($test_mode = FALSE)
-	{
-		if ( ! $this->trans_enabled)
+		elseif (in_array($this->subdriver, array('mssql', 'sybase'), TRUE))
 		{
-			return TRUE;
+			$this->subdriver = 'dblib';
 		}
-
-		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		elseif ($this->subdriver === '4D')
 		{
-			return TRUE;
+			$this->subdriver = '4d';
 		}
-
-		// 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.
-		$this->_trans_failure = (bool) ($test_mode === TRUE);
-
-		return $this->conn_id->beginTransaction();
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Commit Transaction
-	 *
-	 * @access	public
-	 * @return	bool
-	 */
-	function trans_commit()
-	{
-		if ( ! $this->trans_enabled)
+		elseif ( ! in_array($this->subdriver, array('4d', 'cubrid', 'dblib', 'firebird', 'ibm', 'informix', 'mysql', 'oci', 'odbc', 'pgsql', 'sqlite', 'sqlsrv'), TRUE))
 		{
-			return TRUE;
-		}
+			log_message('error', 'PDO: Invalid or non-existent subdriver');
 
-		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
-		{
-			return TRUE;
+			if ($this->db_debug)
+			{
+				show_error('Invalid or non-existent PDO subdriver');
+			}
 		}
 
-		$ret = $this->conn->commit();
-		return $ret;
+		$this->dsn = NULL;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Rollback Transaction
+	 * Database connection
 	 *
-	 * @access	public
-	 * @return	bool
+	 * @param	bool	$persistent
+	 * @return	object
 	 */
-	function trans_rollback()
+	public function db_connect($persistent = FALSE)
 	{
-		if ( ! $this->trans_enabled)
+		if ($persistent === TRUE)
 		{
-			return TRUE;
+			$this->options[PDO::ATTR_PERSISTENT] = TRUE;
 		}
 
-		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		try
 		{
-			return TRUE;
+			return new PDO($this->dsn, $this->username, $this->password, $this->options);
 		}
-
-		$ret = $this->conn_id->rollBack();
-		return $ret;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Escape String
-	 *
-	 * @access	public
-	 * @param	string
-	 * @param	bool	whether or not the string will be used in a LIKE condition
-	 * @return	string
-	 */
-	function escape_str($str, $like = FALSE)
-	{
-		if (is_array($str))
+		catch (PDOException $e)
 		{
-			foreach ($str as $key => $val)
+			if ($this->db_debug && empty($this->failover))
 			{
-				$str[$key] = $this->escape_str($val, $like);
+				$this->display_error($e->getMessage(), '', TRUE);
 			}
 
-			return $str;
-		}
-		
-		//Escape the string
-		$str = $this->conn_id->quote($str);
-		
-		//If there are duplicated quotes, trim them away
-		if (strpos($str, "'") === 0)
-		{
-			$str = substr($str, 1, -1);
-		}
-		
-		// escape LIKE condition wildcards
-		if ($like === TRUE)
-		{
-			$str = 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
-	 *
-	 * @access	public
-	 * @return	integer
-	 */
-	function affected_rows()
-	{
-		return $this->affect_rows;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Insert ID
-	 * 
-	 * @access	public
-	 * @return	integer
-	 */
-	function insert_id($name=NULL)
-	{
-		//Convenience method for postgres insertid
-		if (strpos($this->hostname, 'pgsql') !== FALSE)
-		{
-			$v = $this->_version();
-
-			$table	= func_num_args() > 0 ? func_get_arg(0) : NULL;
-
-			if ($table == NULL && $v >= '8.1')
-			{
-				$sql='SELECT LASTVAL() as ins_id';
-			}
-			$query = $this->query($sql);
-			$row = $query->row();
-			return $row->ins_id;
-		}
-		else
-		{
-			return $this->conn_id->lastInsertId($name);
+			return FALSE;
 		}
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * "Count All" query
-	 *
-	 * Generates a platform-specific query string that counts all records in
-	 * the specified database
+	 * Database version number
 	 *
-	 * @access	public
-	 * @param	string
 	 * @return	string
 	 */
-	function count_all($table = '')
+	public function version()
 	{
-		if ($table == '')
+		if (isset($this->data_cache['version']))
 		{
-			return 0;
+			return $this->data_cache['version'];
 		}
 
-		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
-
-		if ($query->num_rows() == 0)
+		// Not all subdrivers support the getAttribute() method
+		try
 		{
-			return 0;
+			return $this->data_cache['version'] = $this->conn_id->getAttribute(PDO::ATTR_SERVER_VERSION);
 		}
-
-		$row = $query->row();
-		$this->_reset_select();
-		return (int) $row->numrows;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Show table query
-	 *
-	 * Generates a platform-specific query string so that the table names can be fetched
-	 *
-	 * @access	private
-	 * @param	boolean
-	 * @return	string
-	 */
-	function _list_tables($prefix_limit = FALSE)
-	{
-		$sql = "SHOW TABLES FROM `".$this->database."`";
-
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		catch (PDOException $e)
 		{
-			//$sql .= " LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
-			return FALSE; // not currently supported
+			return parent::version();
 		}
-
-		return $sql;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Show column query
-	 *
-	 * Generates a platform-specific query string so that the column names can be fetched
+	 * Execute the query
 	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @return	string
+	 * @param	string	$sql	SQL query
+	 * @return	mixed
 	 */
-	function _list_columns($table = '')
+	protected function _execute($sql)
 	{
-		return "SHOW COLUMNS FROM ".$table;
+		return $this->conn_id->query($sql);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Field data query
-	 *
-	 * Generates a platform-specific query so that the column data can be retrieved
+	 * Begin Transaction
 	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @return	object
+	 * @return	bool
 	 */
-	function _field_data($table)
+	protected function _trans_begin()
 	{
-		return "SELECT TOP 1 FROM ".$table;
+		return $this->conn_id->beginTransaction();
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Commit Transaction
 	 *
-	 * @access	private
-	 * @return	string
+	 * @return	bool
 	 */
-	function _error_message()
+	protected function _trans_commit()
 	{
-		$error_array = $this->conn_id->errorInfo();
-		return $error_array[2];
+		return $this->conn_id->commit();
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message number
+	 * Rollback Transaction
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	bool
 	 */
-	function _error_number()
+	protected function _trans_rollback()
 	{
-		return $this->conn_id->errorCode();
+		return $this->conn_id->rollBack();
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Escape the SQL Identifiers
-	 *
-	 * This function escapes column and table names
+	 * Platform-dependent string escape
 	 *
-	 * @access	private
 	 * @param	string
 	 * @return	string
 	 */
-	function _escape_identifiers($item)
+	protected function _escape_str($str)
 	{
-		if ($this->_escape_char == '')
-		{
-			return $item;
-		}
-
-		foreach ($this->_reserved_identifiers as $id)
-		{
-			if (strpos($item, '.'.$id) !== FALSE)
-			{
-				$str = $this->_escape_char. str_replace('.', $this->_escape_char.'.', $item);
-
-				// remove duplicates if the user already included the escape
-				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
-			}
-		}
-
-		if (strpos($item, '.') !== FALSE)
-		{
-			$str = $this->_escape_char.str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item).$this->_escape_char;
-			
-		}
-		else
-		{
-			$str = $this->_escape_char.$item.$this->_escape_char;
-		}
+		// Escape the string
+		$str = $this->conn_id->quote($str);
 
-		// remove duplicates if the user already included the escape
-		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+		// If there are duplicated quotes, trim them away
+		return ($str[0] === "'")
+			? substr($str, 1, -1)
+			: $str;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
+	 * Affected Rows
 	 *
-	 * @access	public
-	 * @param	type
-	 * @return	type
+	 * @return	int
 	 */
-	function _from_tables($tables)
+	public function affected_rows()
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return (count($tables) == 1) ? $tables[0] : '('.implode(', ', $tables).')';
+		return is_object($this->result_id) ? $this->result_id->rowCount() : 0;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Insert statement
-	 *
-	 * Generates a platform-specific insert string from the supplied data
-	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @param	array	the insert keys
-	 * @param	array	the insert values
-	 * @return	string
-	 */
-	function _insert($table, $keys, $values)
-	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
-	}
-	
-	// --------------------------------------------------------------------
-
-	/**
-	 * Insert_batch statement
-	 *
-	 * Generates a platform-specific insert string from the supplied data
+	 * Insert ID
 	 *
-	 * @access  public
-	 * @param   string  the table name
-	 * @param   array   the insert keys
-	 * @param   array   the insert values
-	 * @return  string
+	 * @param	string	$name
+	 * @return	int
 	 */
-	function _insert_batch($table, $keys, $values)
+	public function insert_id($name = NULL)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES ".implode(', ', $values);
+		return $this->conn_id->lastInsertId($name);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Update statement
+	 * Field data query
 	 *
-	 * Generates a platform-specific update string from the supplied data
+	 * Generates a platform-specific query so that the column data can be retrieved
 	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @param	array	the update data
-	 * @param	array	the where clause
-	 * @param	array	the orderby clause
-	 * @param	array	the limit clause
+	 * @param	string	$table
 	 * @return	string
 	 */
-	function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
+	protected function _field_data($table)
 	{
-		foreach ($values as $key => $val)
-		{
-			$valstr[] = $key." = ".$val;
-		}
-
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
-
-		$orderby = (count($orderby) >= 1)?' ORDER BY '.implode(", ", $orderby):'';
-
-		$sql = "UPDATE ".$table." SET ".implode(', ', $valstr);
-
-		$sql .= ($where != '' AND count($where) >=1) ? " WHERE ".implode(" ", $where) : '';
-
-		$sql .= $orderby.$limit;
-
-		return $sql;
+		return 'SELECT TOP 1 * FROM '.$this->protect_identifiers($table);
 	}
-	
+
 	// --------------------------------------------------------------------
 
 	/**
-	 * Update_Batch statement
+	 * Error
 	 *
-	 * Generates a platform-specific batch update string from the supplied data
+	 * Returns an array containing code and message of the last
+	 * database error that has occurred.
 	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @param	array	the update data
-	 * @param	array	the where clause
-	 * @return	string
+	 * @return	array
 	 */
-	function _update_batch($table, $values, $index, $where = NULL)
+	public function error()
 	{
-		$ids = array();
-		$where = ($where != '' AND count($where) >=1) ? implode(" ", $where).' AND ' : '';
+		$error = array('code' => '00000', 'message' => '');
+		$pdo_error = $this->conn_id->errorInfo();
 
-		foreach ($values as $key => $val)
+		if (empty($pdo_error[0]))
 		{
-			$ids[] = $val[$index];
-
-			foreach (array_keys($val) as $field)
-			{
-				if ($field != $index)
-				{
-					$final[$field][] =  'WHEN '.$index.' = '.$val[$index].' THEN '.$val[$field];
-				}
-			}
+			return $error;
 		}
 
-		$sql = "UPDATE ".$table." SET ";
-		$cases = '';
-
-		foreach ($final as $k => $v)
+		$error['code'] = isset($pdo_error[1]) ? $pdo_error[0].'/'.$pdo_error[1] : $pdo_error[0];
+		if (isset($pdo_error[2]))
 		{
-			$cases .= $k.' = CASE '."\n";
-			foreach ($v as $row)
-			{
-				$cases .= $row."\n";
-			}
-
-			$cases .= 'ELSE '.$k.' END, ';
+			 $error['message'] = $pdo_error[2];
 		}
 
-		$sql .= substr($cases, 0, -2);
-
-		$sql .= ' WHERE '.$where.$index.' IN ('.implode(',', $ids).')';
-
-		return $sql;
+		return $error;
 	}
 
-
 	// --------------------------------------------------------------------
 
 	/**
 	 * Truncate statement
 	 *
 	 * Generates a platform-specific truncate string from the supplied data
-	 * If the database does not support the truncate() command
-	 * This function maps to "DELETE FROM table"
-	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @return	string
-	 */
-	function _truncate($table)
-	{
-		return $this->_delete($table);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Delete statement
-	 *
-	 * Generates a platform-specific delete string from the supplied data
-	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @param	array	the where clause
-	 * @param	string	the limit clause
-	 * @return	string
-	 */
-	function _delete($table, $where = array(), $like = array(), $limit = FALSE)
-	{
-		$conditions = '';
-
-		if (count($where) > 0 OR count($like) > 0)
-		{
-			$conditions = "\nWHERE ";
-			$conditions .= implode("\n", $this->ar_where);
-
-			if (count($where) > 0 && count($like) > 0)
-			{
-				$conditions .= " AND ";
-			}
-			$conditions .= implode("\n", $like);
-		}
-
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
-
-		return "DELETE FROM ".$table.$conditions.$limit;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Limit string
 	 *
-	 * Generates a platform-specific LIMIT clause
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
 	 *
-	 * @access	public
-	 * @param	string	the sql query string
-	 * @param	integer	the number of rows to limit the query to
-	 * @param	integer	the offset value
+	 * @param	string	$table
 	 * @return	string
 	 */
-	function _limit($sql, $limit, $offset)
-	{
-		if (strpos($this->hostname, 'cubrid') !== FALSE || strpos($this->hostname, 'sqlite') !== FALSE)
-		{
-			if ($offset == 0)
-			{
-				$offset = '';
-			}
-			else
-			{
-				$offset .= ", ";
-			}
-
-			return $sql."LIMIT ".$offset.$limit;
-		}
-		else
-		{
-			$sql .= "LIMIT ".$limit;
-
-			if ($offset > 0)
-			{
-				$sql .= " OFFSET ".$offset;
-			}
-			
-			return $sql;
-		}
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Close DB Connection
-	 *
-	 * @access	public
-	 * @param	resource
-	 * @return	void
-	 */
-	function _close($conn_id)
+	protected function _truncate($table)
 	{
-		$this->conn_id = null;
+		return 'TRUNCATE TABLE '.$table;
 	}
 
-
 }
-
-
-
-/* End of file pdo_driver.php */
-/* Location: ./system/database/drivers/pdo/pdo_driver.php */
-\ No newline at end of file
diff --git a/system/database/drivers/pdo/pdo_forge.php b/system/database/drivers/pdo/pdo_forge.php
index f7beb0a9a..685b6776d 100644
--- a/system/database/drivers/pdo/pdo_forge.php
+++ b/system/database/drivers/pdo/pdo_forge.php
@@ -1,266 +1,65 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php
 /**
  * CodeIgniter
  *
- * An open source application development framework for PHP 5.1.6 or newer
+ * An open source application development framework for PHP
  *
- * @package		CodeIgniter
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
- * @author		EllisLab Dev Team
- * @link		http://codeigniter.com
- * @since		Version 2.1.2
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 2.1.0
  * @filesource
  */
-
-// ------------------------------------------------------------------------
+defined('BASEPATH') OR exit('No direct script access allowed');
 
 /**
  * PDO Forge Class
  *
+ * @package		CodeIgniter
+ * @subpackage	Drivers
  * @category	Database
  * @author		EllisLab Dev Team
- * @link		http://codeigniter.com/database/
+ * @link		https://codeigniter.com/database/
  */
 class CI_DB_pdo_forge extends CI_DB_forge {
 
 	/**
-	 * Create database
-	 *
-	 * @access	private
-	 * @param	string	the database name
-	 * @return	bool
-	 */
-	function _create_database()
-	{
-		// PDO has no "create database" command since it's
-		// designed to connect to an existing database
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Drop database
-	 *
-	 * @access	private
-	 * @param	string	the database name
-	 * @return	bool
-	 */
-	function _drop_database($name)
-	{
-		// PDO has no "drop database" command since it's
-		// designed to connect to an existing database
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Create Table
-	 *
-	 * @access	private
-	 * @param	string	the table name
-	 * @param	array	the fields
-	 * @param	mixed	primary key(s)
-	 * @param	mixed	key(s)
-	 * @param	boolean	should 'IF NOT EXISTS' be added to the SQL
-	 * @return	bool
-	 */
-	function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
-	{
-		$sql = 'CREATE TABLE ';
-
-		if ($if_not_exists === TRUE)
-		{
-			$sql .= 'IF NOT EXISTS ';
-		}
-
-		$sql .= $this->db->_escape_identifiers($table)." (";
-		$current_field_count = 0;
-
-		foreach ($fields as $field=>$attributes)
-		{
-			// Numeric field names aren't allowed in databases, so if the key is
-			// numeric, we know it was assigned by PHP and the developer manually
-			// entered the field information, so we'll simply add it to the list
-			if (is_numeric($field))
-			{
-				$sql .= "\n\t$attributes";
-			}
-			else
-			{
-				$attributes = array_change_key_case($attributes, CASE_UPPER);
-
-				$sql .= "\n\t".$this->db->_protect_identifiers($field);
-
-				$sql .=  ' '.$attributes['TYPE'];
-
-				if (array_key_exists('CONSTRAINT', $attributes))
-				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
-				}
-
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
-				{
-					$sql .= ' UNSIGNED';
-				}
-
-				if (array_key_exists('DEFAULT', $attributes))
-				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
-				}
-
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
-
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
-				{
-					$sql .= ' AUTO_INCREMENT';
-				}
-			}
-
-			// don't add a comma on the end of the last field
-			if (++$current_field_count < count($fields))
-			{
-				$sql .= ',';
-			}
-		}
-
-		if (count($primary_keys) > 0)
-		{
-			$primary_keys = $this->db->_protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
-		}
-
-		if (is_array($keys) && count($keys) > 0)
-		{
-			foreach ($keys as $key)
-			{
-				if (is_array($key))
-				{
-					$key = $this->db->_protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->_protect_identifiers($key));
-				}
-
-				$sql .= ",\n\tFOREIGN KEY (" . implode(', ', $key) . ")";
-			}
-		}
-
-		$sql .= "\n)";
-
-		return $sql;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Drop Table
+	 * CREATE TABLE IF statement
 	 *
-	 * @access	private
-	 * @return	bool
+	 * @var	string
 	 */
-	function _drop_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
+	protected $_create_table_if	= FALSE;
 
 	/**
-	 * Alter table query
+	 * DROP TABLE IF statement
 	 *
-	 * Generates a platform-specific query so that a table can be altered
-	 * Called by add_column(), drop_column(), and column_alter(),
-	 *
-	 * @access	private
-	 * @param	string	the ALTER type (ADD, DROP, CHANGE)
-	 * @param	string	the column name
-	 * @param	string	the table name
-	 * @param	string	the column definition
-	 * @param	string	the default value
-	 * @param	boolean	should 'NOT NULL' be added
-	 * @param	string	the field after which we should add the new field
-	 * @return	object
+	 * @var	string
 	 */
-	function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
-	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table)." $alter_type ".$this->db->_protect_identifiers($column_name);
-
-		// DROP has everything it needs now.
-		if ($alter_type == 'DROP')
-		{
-			return $sql;
-		}
-
-		$sql .= " $column_definition";
-
-		if ($default_value != '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field != '')
-		{
-			$sql .= ' AFTER ' . $this->db->_protect_identifiers($after_field);
-		}
-
-		return $sql;
-
-	}
-
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Rename a table
-	 *
-	 * Generates a platform-specific query so that a table can be renamed
-	 *
-	 * @access	private
-	 * @param	string	the old table name
-	 * @param	string	the new table name
-	 * @return	string
-	 */
-	function _rename_table($table_name, $new_table_name)
-	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table_name)." RENAME TO ".$this->db->_protect_identifiers($new_table_name);
-		return $sql;
-	}
-
+	protected $_drop_table_if	= FALSE;
 
 }
-
-/* End of file pdo_forge.php */
-/* Location: ./system/database/drivers/pdo/pdo_forge.php */
-\ No newline at end of file
diff --git a/system/database/drivers/pdo/pdo_result.php b/system/database/drivers/pdo/pdo_result.php
index 4843df43b..bbc2cdc5a 100644
--- a/system/database/drivers/pdo/pdo_result.php
+++ b/system/database/drivers/pdo/pdo_result.php
@@ -1,33 +1,55 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php
 /**
  * CodeIgniter
  *
- * An open source application development framework for PHP 5.1.6 or newer
+ * An open source application development framework for PHP
  *
- * @package		CodeIgniter
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
- * @author		EllisLab Dev Team
- * @link		http://codeigniter.com
- * @since		Version 2.1.2
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 2.1.0
  * @filesource
  */
-
-// ------------------------------------------------------------------------
+defined('BASEPATH') OR exit('No direct script access allowed');
 
 /**
  * PDO Result Class
  *
  * This class extends the parent result class: CI_DB_result
  *
+ * @package		CodeIgniter
+ * @subpackage	Drivers
  * @category	Database
  * @author		EllisLab Dev Team
- * @link		http://codeigniter.com/user_guide/database/
+ * @link		https://codeigniter.com/user_guide/database/
  */
 class CI_DB_pdo_result extends CI_DB_result {
 
-	public $num_rows;
-
 	/**
 	 * Number of rows in the result set
 	 *
@@ -39,14 +61,20 @@ class CI_DB_pdo_result extends CI_DB_result {
 		{
 			return $this->num_rows;
 		}
-		elseif (($this->num_rows = $this->result_id->rowCount()) > 0)
+		elseif (count($this->result_array) > 0)
 		{
-			return $this->num_rows;
+			return $this->num_rows = count($this->result_array);
+		}
+		elseif (count($this->result_object) > 0)
+		{
+			return $this->num_rows = count($this->result_object);
+		}
+		elseif (($num_rows = $this->result_id->rowCount()) > 0)
+		{
+			return $this->num_rows = $num_rows;
 		}
 
-		$this->num_rows = count($this->result_id->fetchAll());
-		$this->result_id->execute();
-		return $this->num_rows;
+		return $this->num_rows = count($this->result_array());
 	}
 
 	// --------------------------------------------------------------------
@@ -54,10 +82,9 @@ class CI_DB_pdo_result extends CI_DB_result {
 	/**
 	 * Number of fields in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_fields()
+	public function num_fields()
 	{
 		return $this->result_id->columnCount();
 	}
@@ -69,16 +96,20 @@ class CI_DB_pdo_result extends CI_DB_result {
 	 *
 	 * Generates an array of column names
 	 *
-	 * @access	public
-	 * @return	array
+	 * @return	bool
 	 */
-	function list_fields()
+	public function list_fields()
 	{
-		if ($this->db->db_debug)
+		$field_names = array();
+		for ($i = 0, $c = $this->num_fields(); $i < $c; $i++)
 		{
-			return $this->db->display_error('db_unsuported_feature');
+			// Might trigger an E_WARNING due to not all subdrivers
+			// supporting getColumnMeta()
+			$field_names[$i] = @$this->result_id->getColumnMeta($i);
+			$field_names[$i] = $field_names[$i]['name'];
 		}
-		return FALSE;
+
+		return $field_names;
 	}
 
 	// --------------------------------------------------------------------
@@ -88,28 +119,34 @@ class CI_DB_pdo_result extends CI_DB_result {
 	 *
 	 * Generates an array of objects containing field meta-data
 	 *
-	 * @access	public
 	 * @return	array
 	 */
-	function field_data()
+	public function field_data()
 	{
-		$data = array();
-	
 		try
 		{
-			for($i = 0; $i < $this->num_fields(); $i++)
+			$retval = array();
+
+			for ($i = 0, $c = $this->num_fields(); $i < $c; $i++)
 			{
-				$data[] = $this->result_id->getColumnMeta($i);
+				$field = $this->result_id->getColumnMeta($i);
+
+				$retval[$i]			= new stdClass();
+				$retval[$i]->name		= $field['name'];
+				$retval[$i]->type		= $field['native_type'];
+				$retval[$i]->max_length		= ($field['len'] > 0) ? $field['len'] : NULL;
+				$retval[$i]->primary_key	= (int) ( ! empty($field['flags']) && in_array('primary_key', $field['flags'], TRUE));
 			}
-			
-			return $data;
+
+			return $retval;
 		}
 		catch (Exception $e)
 		{
 			if ($this->db->db_debug)
 			{
-				return $this->db->display_error('db_unsuported_feature');
+				return $this->db->display_error('db_unsupported_feature');
 			}
+
 			return FALSE;
 		}
 	}
@@ -119,9 +156,9 @@ class CI_DB_pdo_result extends CI_DB_result {
 	/**
 	 * Free the result
 	 *
-	 * @return	null
+	 * @return	void
 	 */
-	function free_result()
+	public function free_result()
 	{
 		if (is_object($this->result_id))
 		{
@@ -132,31 +169,13 @@ class CI_DB_pdo_result extends CI_DB_result {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Data Seek
-	 *
-	 * Moves the internal pointer to the desired offset.  We call
-	 * this internally before fetching results to make sure the
-	 * result set starts at zero
-	 *
-	 * @access	private
-	 * @return	array
-	 */
-	function _data_seek($n = 0)
-	{
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Result - associative array
 	 *
 	 * Returns the result set as an array
 	 *
-	 * @access	private
 	 * @return	array
 	 */
-	function _fetch_assoc()
+	protected function _fetch_assoc()
 	{
 		return $this->result_id->fetch(PDO::FETCH_ASSOC);
 	}
@@ -168,16 +187,12 @@ class CI_DB_pdo_result extends CI_DB_result {
 	 *
 	 * Returns the result set as an object
 	 *
-	 * @access	private
+	 * @param	string	$class_name
 	 * @return	object
 	 */
-	function _fetch_object()
-	{	
-		return $this->result_id->fetchObject();
+	protected function _fetch_object($class_name = 'stdClass')
+	{
+		return $this->result_id->fetchObject($class_name);
 	}
 
 }
-
-
-/* End of file pdo_result.php */
-/* Location: ./system/database/drivers/pdo/pdo_result.php */
-\ No newline at end of file
diff --git a/system/database/drivers/pdo/pdo_utility.php b/system/database/drivers/pdo/pdo_utility.php
index 042ccef8d..5029cac94 100644
--- a/system/database/drivers/pdo/pdo_utility.php
+++ b/system/database/drivers/pdo/pdo_utility.php
@@ -1,103 +1,63 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php
 /**
  * CodeIgniter
  *
- * An open source application development framework for PHP 5.1.6 or newer
+ * An open source application development framework for PHP
  *
- * @package		CodeIgniter
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
- * @author		EllisLab Dev Team
- * @link		http://codeigniter.com
- * @since		Version 2.1.2
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 2.1.0
  * @filesource
  */
-
-// ------------------------------------------------------------------------
+defined('BASEPATH') OR exit('No direct script access allowed');
 
 /**
  * PDO Utility Class
  *
+ * @package		CodeIgniter
+ * @subpackage	Drivers
  * @category	Database
  * @author		EllisLab Dev Team
- * @link		http://codeigniter.com/database/
+ * @link		https://codeigniter.com/database/
  */
 class CI_DB_pdo_utility extends CI_DB_utility {
 
 	/**
-	 * List databases
-	 *
-	 * @access	private
-	 * @return	bool
-	 */
-	function _list_databases()
-	{
-		// Not sure if PDO lets you list all databases...
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Optimize table query
-	 *
-	 * Generates a platform-specific query so that a table can be optimized
+	 * Export
 	 *
-	 * @access	private
-	 * @param	string	the table name
-	 * @return	object
-	 */
-	function _optimize_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Repair table query
-	 *
-	 * Generates a platform-specific query so that a table can be repaired
-	 *
-	 * @access	private
-	 * @param	string	the table name
-	 * @return	object
-	 */
-	function _repair_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * PDO Export
-	 *
-	 * @access	private
-	 * @param	array	Preferences
+	 * @param	array	$params	Preferences
 	 * @return	mixed
 	 */
-	function _backup($params = array())
+	protected function _backup($params = array())
 	{
 		// Currently unsupported
-		return $this->db->display_error('db_unsuported_feature');
+		return $this->db->display_error('db_unsupported_feature');
 	}
 
 }
-
-/* End of file pdo_utility.php */
-/* Location: ./system/database/drivers/pdo/pdo_utility.php */
-\ No newline at end of file
diff --git a/system/database/drivers/pdo/subdrivers/index.html b/system/database/drivers/pdo/subdrivers/index.html
new file mode 100644
index 000000000..b702fbc39
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/index.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+<head>
+	<title>403 Forbidden</title>
+</head>
+<body>
+
+<p>Directory access is forbidden.</p>
+
+</body>
+</html>
diff --git a/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php b/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php
new file mode 100644
index 000000000..7eaeaa1fd
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php
@@ -0,0 +1,200 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO 4D 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/user_guide/database/
+ */
+class CI_DB_pdo_4d_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = '4d';
+
+	/**
+	 * Identifier escape character
+	 *
+	 * @var	string[]
+	 */
+	protected $_escape_char = array('[', ']');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = '4D:host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ';port='.$this->port;
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+		}
+		elseif ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 3) === FALSE)
+		{
+			$this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT '.$this->escape_identifiers('TABLE_NAME').' FROM '.$this->escape_identifiers('_USER_TABLES');
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' WHERE '.$this->escape_identifiers('TABLE_NAME')." LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		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 'SELECT '.$this->escape_identifiers('COLUMN_NAME').' FROM '.$this->escape_identifiers('_USER_COLUMNS')
+			.' WHERE '.$this->escape_identifiers('TABLE_NAME').' = '.$this->escape($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field data query
+	 *
+	 * Generates a platform-specific query so that the column data can be retrieved
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _field_data($table)
+	{
+		return 'SELECT * FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE).' LIMIT 1';
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		return $sql.' LIMIT '.$this->qb_limit.($this->qb_offset ? ' OFFSET '.$this->qb_offset : '');
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_4d_forge.php b/system/database/drivers/pdo/subdrivers/pdo_4d_forge.php
new file mode 100644
index 000000000..3f636d3bd
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_4d_forge.php
@@ -0,0 +1,217 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO 4D Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_4d_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_database	= 'CREATE SCHEMA %s';
+
+	/**
+	 * DROP DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_database	= 'DROP SCHEMA %s';
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= 'CREATE TABLE IF NOT EXISTS';
+
+	/**
+	 * RENAME TABLE statement
+	 *
+	 * @var	string
+	 */
+	protected $_rename_table	= FALSE;
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= 'DROP TABLE IF EXISTS';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'INT16'		=> 'INT',
+		'SMALLINT'	=> 'INT',
+		'INT'		=> 'INT64',
+		'INT32'		=> 'INT64'
+	);
+
+	/**
+	 * DEFAULT value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_default		= FALSE;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if (in_array($alter_type, array('ADD', 'DROP'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		// No method of modifying columns is supported
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process column
+	 *
+	 * @param	array	$field
+	 * @return	string
+	 */
+	protected function _process_column($field)
+	{
+		return $this->db->escape_identifiers($field['name'])
+			.' '.$field['type'].$field['length']
+			.$field['null']
+			.$field['unique']
+			.$field['auto_increment'];
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'INTEGER':
+				$attributes['TYPE'] = 'INT';
+				return;
+			case 'BIGINT':
+				$attributes['TYPE'] = 'INT64';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute UNIQUE
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_unique(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+		{
+			$field['unique'] = ' UNIQUE';
+
+			// UNIQUE must be used with NOT NULL
+			$field['null'] = ' NOT NULL';
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+		{
+			if (stripos($field['type'], 'int') !== FALSE)
+			{
+				$field['auto_increment'] = ' AUTO_INCREMENT';
+			}
+			elseif (strcasecmp($field['type'], 'UUID') === 0)
+			{
+				$field['auto_increment'] = ' AUTO_GENERATE';
+			}
+		}
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_cubrid_driver.php b/system/database/drivers/pdo/subdrivers/pdo_cubrid_driver.php
new file mode 100644
index 000000000..fc49e0dd0
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_cubrid_driver.php
@@ -0,0 +1,209 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO CUBRID 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/user_guide/database/
+ */
+class CI_DB_pdo_cubrid_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'cubrid';
+
+	/**
+	 * Identifier escape character
+	 *
+	 * @var	string
+	 */
+	protected $_escape_char = '`';
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var array
+	 */
+	protected $_random_keyword = array('RANDOM()', 'RANDOM(%d)');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'cubrid:host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ';port='.$this->port;
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SHOW TABLES';
+
+		if ($prefix_limit === TRUE && $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;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'TRUNCATE '.$table;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * FROM tables
+	 *
+	 * Groups tables in FROM clauses if needed, so there is no confusion
+	 * about operator precedence.
+	 *
+	 * @return	string
+	 */
+	protected function _from_tables()
+	{
+		if ( ! empty($this->qb_join) && count($this->qb_from) > 1)
+		{
+			return '('.implode(', ', $this->qb_from).')';
+		}
+
+		return implode(', ', $this->qb_from);
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_cubrid_forge.php b/system/database/drivers/pdo/subdrivers/pdo_cubrid_forge.php
new file mode 100644
index 000000000..276cbb6bc
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_cubrid_forge.php
@@ -0,0 +1,230 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO CUBRID Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_cubrid_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_database	= FALSE;
+
+	/**
+	 * DROP DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_database	= FALSE;
+
+	/**
+	 * CREATE TABLE keys flag
+	 *
+	 * Whether table keys are created from within the
+	 * CREATE TABLE statement.
+	 *
+	 * @var	bool
+	 */
+	protected $_create_table_keys	= TRUE;
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= 'DROP TABLE IF EXISTS';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'SHORT'		=> 'INTEGER',
+		'SMALLINT'	=> 'INTEGER',
+		'INT'		=> 'BIGINT',
+		'INTEGER'	=> 'BIGINT',
+		'BIGINT'	=> 'NUMERIC',
+		'FLOAT'		=> 'DOUBLE',
+		'REAL'		=> 'DOUBLE'
+	);
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if (in_array($alter_type, array('DROP', 'ADD'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			if ($field[$i]['_literal'] !== FALSE)
+			{
+				$sqls[] = $sql.' CHANGE '.$field[$i]['_literal'];
+			}
+			else
+			{
+				$alter_type = empty($field[$i]['new_name']) ? ' MODIFY ' : ' CHANGE ';
+				$sqls[] = $sql.$alter_type.$this->_process_column($field[$i]);
+			}
+		}
+
+		return $sqls;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process column
+	 *
+	 * @param	array	$field
+	 * @return	string
+	 */
+	protected function _process_column($field)
+	{
+		$extra_clause = isset($field['after'])
+			? ' AFTER '.$this->db->escape_identifiers($field['after']) : '';
+
+		if (empty($extra_clause) && isset($field['first']) && $field['first'] === TRUE)
+		{
+			$extra_clause = ' FIRST';
+		}
+
+		return $this->db->escape_identifiers($field['name'])
+			.(empty($field['new_name']) ? '' : ' '.$this->db->escape_identifiers($field['new_name']))
+			.' '.$field['type'].$field['length']
+			.$field['unsigned']
+			.$field['null']
+			.$field['default']
+			.$field['auto_increment']
+			.$field['unique']
+			.$extra_clause;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'LONGTEXT':
+				$attributes['TYPE'] = 'STRING';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process indexes
+	 *
+	 * @param	string	$table	(ignored)
+	 * @return	string
+	 */
+	protected function _process_indexes($table)
+	{
+		$sql = '';
+
+		for ($i = 0, $c = count($this->keys); $i < $c; $i++)
+		{
+			if (is_array($this->keys[$i]))
+			{
+				for ($i2 = 0, $c2 = count($this->keys[$i]); $i2 < $c2; $i2++)
+				{
+					if ( ! isset($this->fields[$this->keys[$i][$i2]]))
+					{
+						unset($this->keys[$i][$i2]);
+						continue;
+					}
+				}
+			}
+			elseif ( ! isset($this->fields[$this->keys[$i]]))
+			{
+				unset($this->keys[$i]);
+				continue;
+			}
+
+			is_array($this->keys[$i]) OR $this->keys[$i] = array($this->keys[$i]);
+
+			$sql .= ",\n\tKEY ".$this->db->escape_identifiers(implode('_', $this->keys[$i]))
+				.' ('.implode(', ', $this->db->escape_identifiers($this->keys[$i])).')';
+		}
+
+		$this->keys = array();
+
+		return $sql;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
new file mode 100644
index 000000000..08243232e
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
@@ -0,0 +1,337 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO DBLIB 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/user_guide/database/
+ */
+class CI_DB_pdo_dblib_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'dblib';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('NEWID()', 'RAND(%d)');
+
+	/**
+	 * Quoted identifier flag
+	 *
+	 * Whether to use SQL-92 standard quoted identifier
+	 * (double quotes) or brackets for identifier escaping.
+	 *
+	 * @var	bool
+	 */
+	protected $_quoted_identifier;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = $params['subdriver'].':host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			if ( ! empty($this->port))
+			{
+				$this->dsn .= (DIRECTORY_SEPARATOR === '\\' ? ',' : ':').$this->port;
+			}
+
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+			empty($this->appname) OR $this->dsn .= ';appname='.$this->appname;
+		}
+		else
+		{
+			if ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 6) === FALSE)
+			{
+				$this->dsn .= ';charset='.$this->char_set;
+			}
+
+			$this->subdriver = 'dblib';
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database connection
+	 *
+	 * @param	bool	$persistent
+	 * @return	object
+	 */
+	public function db_connect($persistent = FALSE)
+	{
+		if ($persistent === TRUE)
+		{
+			log_message('debug', "dblib driver doesn't support persistent connections");
+		}
+
+		$this->conn_id = parent::db_connect(FALSE);
+
+		if ( ! is_object($this->conn_id))
+		{
+			return $this->conn_id;
+		}
+
+		// Determine how identifiers are escaped
+		$query = $this->query('SELECT CASE WHEN (@@OPTIONS | 256) = @@OPTIONS THEN 1 ELSE 0 END AS qi');
+		$query = $query->row_array();
+		$this->_quoted_identifier = empty($query) ? FALSE : (bool) $query['qi'];
+		$this->_escape_char = ($this->_quoted_identifier) ? '"' : array('[', ']');
+
+		return $this->conn_id;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT '.$this->escape_identifiers('name')
+			.' FROM '.$this->escape_identifiers('sysobjects')
+			.' WHERE '.$this->escape_identifiers('type')." = 'U'";
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' AND '.$this->escape_identifiers('name')." LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		return $sql.' ORDER BY '.$this->escape_identifiers('name');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * 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 'SELECT COLUMN_NAME
+			FROM INFORMATION_SCHEMA.Columns
+			WHERE UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, COLUMN_DEFAULT
+			FROM INFORMATION_SCHEMA.Columns
+			WHERE UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+
+		if (($query = $this->query($sql)) === 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]->COLUMN_NAME;
+			$retval[$i]->type		= $query[$i]->DATA_TYPE;
+			$retval[$i]->max_length		= ($query[$i]->CHARACTER_MAXIMUM_LENGTH > 0) ? $query[$i]->CHARACTER_MAXIMUM_LENGTH : $query[$i]->NUMERIC_PRECISION;
+			$retval[$i]->default		= $query[$i]->COLUMN_DEFAULT;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		if ($this->qb_limit)
+		{
+			return 'WITH ci_delete AS (SELECT TOP '.$this->qb_limit.' * FROM '.$table.$this->_compile_wh('qb_where').') DELETE FROM ci_delete';
+		}
+
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		$limit = $this->qb_offset + $this->qb_limit;
+
+		// As of SQL Server 2005 (9.0.*) ROW_NUMBER() is supported,
+		// however an ORDER BY clause is required for it to work
+		if (version_compare($this->version(), '9', '>=') && $this->qb_offset && ! empty($this->qb_orderby))
+		{
+			$orderby = $this->_compile_order_by();
+
+			// We have to strip the ORDER BY clause
+			$sql = trim(substr($sql, 0, strrpos($sql, $orderby)));
+
+			// Get the fields to select from our subquery, so that we can avoid CI_rownum appearing in the actual results
+			if (count($this->qb_select) === 0)
+			{
+				$select = '*'; // Inevitable
+			}
+			else
+			{
+				// Use only field names and their aliases, everything else is out of our scope.
+				$select = array();
+				$field_regexp = ($this->_quoted_identifier)
+					? '("[^\"]+")' : '(\[[^\]]+\])';
+				for ($i = 0, $c = count($this->qb_select); $i < $c; $i++)
+				{
+					$select[] = preg_match('/(?:\s|\.)'.$field_regexp.'$/i', $this->qb_select[$i], $m)
+						? $m[1] : $this->qb_select[$i];
+				}
+				$select = implode(', ', $select);
+			}
+
+			return 'SELECT '.$select." FROM (\n\n"
+				.preg_replace('/^(SELECT( DISTINCT)?)/i', '\\1 ROW_NUMBER() OVER('.trim($orderby).') AS '.$this->escape_identifiers('CI_rownum').', ', $sql)
+				."\n\n) ".$this->escape_identifiers('CI_subquery')
+				."\nWHERE ".$this->escape_identifiers('CI_rownum').' BETWEEN '.($this->qb_offset + 1).' AND '.$limit;
+		}
+
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$limit.' ', $sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert batch statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data.
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return	string|bool
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		// Multiple-value inserts are only supported as of SQL Server 2008
+		if (version_compare($this->version(), '10', '>='))
+		{
+			return parent::_insert_batch($table, $keys, $values);
+		}
+
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_dblib_forge.php b/system/database/drivers/pdo/subdrivers/pdo_dblib_forge.php
new file mode 100644
index 000000000..d0cca38dd
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_dblib_forge.php
@@ -0,0 +1,149 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO DBLIB Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_dblib_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= "IF NOT EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nCREATE TABLE";
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= "IF EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nDROP TABLE";
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'TINYINT'	=> 'SMALLINT',
+		'SMALLINT'	=> 'INT',
+		'INT'		=> 'BIGINT',
+		'REAL'		=> 'FLOAT'
+	);
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if (in_array($alter_type, array('ADD', 'DROP'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' ALTER COLUMN ';
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			$sqls[] = $sql.$this->_process_column($field[$i]);
+		}
+
+		return $sqls;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		if (isset($attributes['CONSTRAINT']) && strpos($attributes['TYPE'], 'INT') !== FALSE)
+		{
+			unset($attributes['CONSTRAINT']);
+		}
+
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'INTEGER':
+				$attributes['TYPE'] = 'INT';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE && stripos($field['type'], 'int') !== FALSE)
+		{
+			$field['auto_increment'] = ' IDENTITY(1,1)';
+		}
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
new file mode 100644
index 000000000..cb93f19b7
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
@@ -0,0 +1,279 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Firebird 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/user_guide/database/
+ */
+class CI_DB_pdo_firebird_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'firebird';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('RAND()', 'RAND()');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'firebird:';
+
+			if ( ! empty($this->database))
+			{
+				$this->dsn .= 'dbname='.$this->database;
+			}
+			elseif ( ! empty($this->hostname))
+			{
+				$this->dsn .= 'dbname='.$this->hostname;
+			}
+
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+			empty($this->role) OR $this->dsn .= ';role='.$this->role;
+		}
+		elseif ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 9) === FALSE)
+		{
+			$this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "RDB$RELATION_NAME" FROM "RDB$RELATIONS" WHERE "RDB$RELATION_NAME" NOT LIKE \'RDB$%\' AND "RDB$RELATION_NAME" NOT LIKE \'MON$%\'';
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			return $sql.' AND "RDB$RELATION_NAME" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		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 'SELECT "RDB$FIELD_NAME" FROM "RDB$RELATION_FIELDS" WHERE "RDB$RELATION_NAME" = '.$this->escape($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT "rfields"."RDB$FIELD_NAME" AS "name",
+				CASE "fields"."RDB$FIELD_TYPE"
+					WHEN 7 THEN \'SMALLINT\'
+					WHEN 8 THEN \'INTEGER\'
+					WHEN 9 THEN \'QUAD\'
+					WHEN 10 THEN \'FLOAT\'
+					WHEN 11 THEN \'DFLOAT\'
+					WHEN 12 THEN \'DATE\'
+					WHEN 13 THEN \'TIME\'
+					WHEN 14 THEN \'CHAR\'
+					WHEN 16 THEN \'INT64\'
+					WHEN 27 THEN \'DOUBLE\'
+					WHEN 35 THEN \'TIMESTAMP\'
+					WHEN 37 THEN \'VARCHAR\'
+					WHEN 40 THEN \'CSTRING\'
+					WHEN 261 THEN \'BLOB\'
+					ELSE NULL
+				END AS "type",
+				"fields"."RDB$FIELD_LENGTH" AS "max_length",
+				"rfields"."RDB$DEFAULT_VALUE" AS "default"
+			FROM "RDB$RELATION_FIELDS" "rfields"
+				JOIN "RDB$FIELDS" "fields" ON "rfields"."RDB$FIELD_SOURCE" = "fields"."RDB$FIELD_NAME"
+			WHERE "rfields"."RDB$RELATION_NAME" = '.$this->escape($table).'
+			ORDER BY "rfields"."RDB$FIELD_POSITION"';
+
+		return (($query = $this->query($sql)) !== FALSE)
+			? $query->result_object()
+			: FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'DELETE FROM '.$table;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		// Limit clause depends on if Interbase or Firebird
+		if (stripos($this->version(), 'firebird') !== FALSE)
+		{
+			$select = 'FIRST '.$this->qb_limit
+				.($this->qb_offset > 0 ? ' SKIP '.$this->qb_offset : '');
+		}
+		else
+		{
+			$select = 'ROWS '
+				.($this->qb_offset > 0 ? $this->qb_offset.' TO '.($this->qb_limit + $this->qb_offset) : $this->qb_limit);
+		}
+
+		return preg_replace('`SELECT`i', 'SELECT '.$select, $sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert batch statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data.
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return	string|bool
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
+	}
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php b/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php
new file mode 100644
index 000000000..20c5a6897
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php
@@ -0,0 +1,237 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Firebird Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_firebird_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * RENAME TABLE statement
+	 *
+	 * @var	string
+	 */
+	protected $_rename_table	= FALSE;
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'SMALLINT'	=> 'INTEGER',
+		'INTEGER'	=> 'INT64',
+		'FLOAT'		=> 'DOUBLE PRECISION'
+	);
+
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null		= 'NULL';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Create database
+	 *
+	 * @param	string	$db_name
+	 * @return	string
+	 */
+	public function create_database($db_name)
+	{
+		// Firebird databases are flat files, so a path is required
+
+		// Hostname is needed for remote access
+		empty($this->db->hostname) OR $db_name = $this->hostname.':'.$db_name;
+
+		return parent::create_database('"'.$db_name.'"');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Drop database
+	 *
+	 * @param	string	$db_name	(ignored)
+	 * @return	bool
+	 */
+	public function drop_database($db_name)
+	{
+		if ( ! ibase_drop_db($this->conn_id))
+		{
+			return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
+		}
+		elseif ( ! empty($this->db->data_cache['db_names']))
+		{
+			$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				unset($this->db->data_cache['db_names'][$key]);
+			}
+		}
+
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+ 	{
+		if (in_array($alter_type, array('DROP', 'ADD'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			if ($field[$i]['_literal'] !== FALSE)
+			{
+				return FALSE;
+			}
+
+			if (isset($field[$i]['type']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' TYPE '.$field[$i]['type'].$field[$i]['length'];
+			}
+
+			if ( ! empty($field[$i]['default']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' SET DEFAULT '.$field[$i]['default'];
+			}
+
+			if (isset($field[$i]['null']))
+			{
+				$sqls[] = 'UPDATE "RDB$RELATION_FIELDS" SET "RDB$NULL_FLAG" = '
+					.($field[$i]['null'] === TRUE ? 'NULL' : '1')
+					.' WHERE "RDB$FIELD_NAME" = '.$this->db->escape($field[$i]['name'])
+					.' AND "RDB$RELATION_NAME" = '.$this->db->escape($table);
+			}
+
+			if ( ! empty($field[$i]['new_name']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' TO '.$this->db->escape_identifiers($field[$i]['new_name']);
+			}
+		}
+
+		return $sqls;
+ 	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process column
+	 *
+	 * @param	array	$field
+	 * @return	string
+	 */
+	protected function _process_column($field)
+	{
+		return $this->db->escape_identifiers($field['name'])
+			.' '.$field['type'].$field['length']
+			.$field['null']
+			.$field['unique']
+			.$field['default'];
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'INT':
+				$attributes['TYPE'] = 'INTEGER';
+				return;
+			case 'BIGINT':
+				$attributes['TYPE'] = 'INT64';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		// Not supported
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_ibm_driver.php b/system/database/drivers/pdo/subdrivers/pdo_ibm_driver.php
new file mode 100644
index 000000000..26b556a78
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_ibm_driver.php
@@ -0,0 +1,244 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO IBM DB2 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/user_guide/database/
+ */
+class CI_DB_pdo_ibm_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'ibm';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'ibm:';
+
+			// Pre-defined DSN
+			if (empty($this->hostname) && empty($this->HOSTNAME) && empty($this->port) && empty($this->PORT))
+			{
+				if (isset($this->DSN))
+				{
+					$this->dsn .= 'DSN='.$this->DSN;
+				}
+				elseif ( ! empty($this->database))
+				{
+					$this->dsn .= 'DSN='.$this->database;
+				}
+
+				return;
+			}
+
+			$this->dsn .= 'DRIVER='.(isset($this->DRIVER) ? '{'.$this->DRIVER.'}' : '{IBM DB2 ODBC DRIVER}').';';
+
+			if (isset($this->DATABASE))
+			{
+				$this->dsn .= 'DATABASE='.$this->DATABASE.';';
+			}
+			elseif ( ! empty($this->database))
+			{
+				$this->dsn .= 'DATABASE='.$this->database.';';
+			}
+
+			if (isset($this->HOSTNAME))
+			{
+				$this->dsn .= 'HOSTNAME='.$this->HOSTNAME.';';
+			}
+			else
+			{
+				$this->dsn .= 'HOSTNAME='.(empty($this->hostname) ? '127.0.0.1;' : $this->hostname.';');
+			}
+
+			if (isset($this->PORT))
+			{
+				$this->dsn .= 'PORT='.$this->port.';';
+			}
+			elseif ( ! empty($this->port))
+			{
+				$this->dsn .= ';PORT='.$this->port.';';
+			}
+
+			$this->dsn .= 'PROTOCOL='.(isset($this->PROTOCOL) ? $this->PROTOCOL.';' : 'TCPIP;');
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "tabname" FROM "syscat"."tables"
+			WHERE "type" = \'T\' AND LOWER("tabschema") = '.$this->escape(strtolower($this->database));
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' AND "tabname" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show column query
+	 *
+	 * Generates a platform-specific query string so that the column names can be fetched
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	protected function _list_columns($table = '')
+	{
+		return 'SELECT "colname" FROM "syscat"."columns"
+			WHERE LOWER("tabschema") = '.$this->escape(strtolower($this->database)).'
+				AND LOWER("tabname") = '.$this->escape(strtolower($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT "colname" AS "name", "typename" AS "type", "default" AS "default", "length" AS "max_length",
+				CASE "keyseq" WHEN NULL THEN 0 ELSE 1 END AS "primary_key"
+			FROM "syscat"."columns"
+			WHERE LOWER("tabschema") = '.$this->escape(strtolower($this->database)).'
+				AND LOWER("tabname") = '.$this->escape(strtolower($table)).'
+			ORDER BY "colno"';
+
+		return (($query = $this->query($sql)) !== FALSE)
+			? $query->result_object()
+			: FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		$sql .= ' FETCH FIRST '.($this->qb_limit + $this->qb_offset).' ROWS ONLY';
+
+		return ($this->qb_offset)
+			? 'SELECT * FROM ('.$sql.') WHERE rownum > '.$this->qb_offset
+			: $sql;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_ibm_forge.php b/system/database/drivers/pdo/subdrivers/pdo_ibm_forge.php
new file mode 100644
index 000000000..4238ca082
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_ibm_forge.php
@@ -0,0 +1,154 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO IBM DB2 Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_ibm_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * RENAME TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_rename_table	= 'RENAME TABLE %s TO %s';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'SMALLINT'	=> 'INTEGER',
+		'INT'		=> 'BIGINT',
+		'INTEGER'	=> 'BIGINT'
+	);
+
+	/**
+	 * DEFAULT value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_default		= FALSE;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if ($alter_type === 'CHANGE')
+		{
+			$alter_type = 'MODIFY';
+		}
+
+		return parent::_alter_table($alter_type, $table, $field);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute UNIQUE
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_unique(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+		{
+			$field['unique'] = ' UNIQUE';
+
+			// UNIQUE must be used with NOT NULL
+			$field['null'] = ' NOT NULL';
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		// Not supported
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_informix_driver.php b/system/database/drivers/pdo/subdrivers/pdo_informix_driver.php
new file mode 100644
index 000000000..050171f64
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_informix_driver.php
@@ -0,0 +1,309 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Informix 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/user_guide/database/
+ */
+class CI_DB_pdo_informix_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'informix';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('ASC', 'ASC'); // Currently not supported
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'informix:';
+
+			// Pre-defined DSN
+			if (empty($this->hostname) && empty($this->host) && empty($this->port) && empty($this->service))
+			{
+				if (isset($this->DSN))
+				{
+					$this->dsn .= 'DSN='.$this->DSN;
+				}
+				elseif ( ! empty($this->database))
+				{
+					$this->dsn .= 'DSN='.$this->database;
+				}
+
+				return;
+			}
+
+			if (isset($this->host))
+			{
+				$this->dsn .= 'host='.$this->host;
+			}
+			else
+			{
+				$this->dsn .= 'host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+			}
+
+			if (isset($this->service))
+			{
+				$this->dsn .= '; service='.$this->service;
+			}
+			elseif ( ! empty($this->port))
+			{
+				$this->dsn .= '; service='.$this->port;
+			}
+
+			empty($this->database) OR $this->dsn .= '; database='.$this->database;
+			empty($this->server) OR $this->dsn .= '; server='.$this->server;
+
+			$this->dsn .= '; protocol='.(isset($this->protocol) ? $this->protocol : 'onsoctcp')
+				.'; EnableScrollableCursors=1';
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "tabname" FROM "systables"
+			WHERE "tabid" > 99 AND "tabtype" = \'T\' AND LOWER("owner") = '.$this->escape(strtolower($this->username));
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' AND "tabname" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		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 = '')
+	{
+		if (strpos($table, '.') !== FALSE)
+		{
+			sscanf($table, '%[^.].%s', $owner, $table);
+		}
+		else
+		{
+			$owner = $this->username;
+		}
+
+		return 'SELECT "colname" FROM "systables", "syscolumns"
+			WHERE "systables"."tabid" = "syscolumns"."tabid"
+				AND "systables"."tabtype" = \'T\'
+				AND LOWER("systables"."owner") = '.$this->escape(strtolower($owner)).'
+				AND LOWER("systables"."tabname") = '.$this->escape(strtolower($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT "syscolumns"."colname" AS "name",
+				CASE "syscolumns"."coltype"
+					WHEN 0 THEN \'CHAR\'
+					WHEN 1 THEN \'SMALLINT\'
+					WHEN 2 THEN \'INTEGER\'
+					WHEN 3 THEN \'FLOAT\'
+					WHEN 4 THEN \'SMALLFLOAT\'
+					WHEN 5 THEN \'DECIMAL\'
+					WHEN 6 THEN \'SERIAL\'
+					WHEN 7 THEN \'DATE\'
+					WHEN 8 THEN \'MONEY\'
+					WHEN 9 THEN \'NULL\'
+					WHEN 10 THEN \'DATETIME\'
+					WHEN 11 THEN \'BYTE\'
+					WHEN 12 THEN \'TEXT\'
+					WHEN 13 THEN \'VARCHAR\'
+					WHEN 14 THEN \'INTERVAL\'
+					WHEN 15 THEN \'NCHAR\'
+					WHEN 16 THEN \'NVARCHAR\'
+					WHEN 17 THEN \'INT8\'
+					WHEN 18 THEN \'SERIAL8\'
+					WHEN 19 THEN \'SET\'
+					WHEN 20 THEN \'MULTISET\'
+					WHEN 21 THEN \'LIST\'
+					WHEN 22 THEN \'Unnamed ROW\'
+					WHEN 40 THEN \'LVARCHAR\'
+					WHEN 41 THEN \'BLOB/CLOB/BOOLEAN\'
+					WHEN 4118 THEN \'Named ROW\'
+					ELSE "syscolumns"."coltype"
+				END AS "type",
+				"syscolumns"."collength" as "max_length",
+				CASE "sysdefaults"."type"
+					WHEN \'L\' THEN "sysdefaults"."default"
+					ELSE NULL
+				END AS "default"
+			FROM "syscolumns", "systables", "sysdefaults"
+			WHERE "syscolumns"."tabid" = "systables"."tabid"
+				AND "systables"."tabid" = "sysdefaults"."tabid"
+				AND "syscolumns"."colno" = "sysdefaults"."colno"
+				AND "systables"."tabtype" = \'T\'
+				AND LOWER("systables"."owner") = '.$this->escape(strtolower($this->username)).'
+				AND LOWER("systables"."tabname") = '.$this->escape(strtolower($table)).'
+			ORDER BY "syscolumns"."colno"';
+
+		return (($query = $this->query($sql)) !== FALSE)
+			? $query->result_object()
+			: FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'TRUNCATE TABLE ONLY '.$table;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	$SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		$select = 'SELECT '.($this->qb_offset ? 'SKIP '.$this->qb_offset : '').'FIRST '.$this->qb_limit.' ';
+		return preg_replace('/^(SELECT\s)/i', $select, $sql, 1);
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_informix_forge.php b/system/database/drivers/pdo/subdrivers/pdo_informix_forge.php
new file mode 100644
index 000000000..2ddc2a933
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_informix_forge.php
@@ -0,0 +1,163 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Informix Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_informix_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * RENAME TABLE statement
+	 *
+	 * @var	string
+	 */
+	protected $_rename_table	= 'RENAME TABLE %s TO %s';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'SMALLINT'	=> 'INTEGER',
+		'INT'		=> 'BIGINT',
+		'INTEGER'	=> 'BIGINT',
+		'REAL'		=> 'DOUBLE PRECISION',
+		'SMALLFLOAT'	=> 'DOUBLE PRECISION'
+	);
+
+	/**
+	 * DEFAULT value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_default		= ', ';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if ($alter_type === 'CHANGE')
+		{
+			$alter_type = 'MODIFY';
+		}
+
+		return parent::_alter_table($alter_type, $table, $field);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'BYTE':
+			case 'TEXT':
+			case 'BLOB':
+			case 'CLOB':
+				$attributes['UNIQUE'] = FALSE;
+				if (isset($attributes['DEFAULT']))
+				{
+					unset($attributes['DEFAULT']);
+				}
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute UNIQUE
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_unique(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+		{
+			$field['unique'] = ' UNIQUE CONSTRAINT '.$this->db->escape_identifiers($field['name']);
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		// Not supported
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
new file mode 100644
index 000000000..64b13d827
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
@@ -0,0 +1,374 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO 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/user_guide/database/
+ */
+class CI_DB_pdo_mysql_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'mysql';
+
+	/**
+	 * Compression flag
+	 *
+	 * @var	bool
+	 */
+	public $compress = FALSE;
+
+	/**
+	 * 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
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'mysql:host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ';port='.$this->port;
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+		}
+		elseif ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 6) === FALSE)
+		{
+			$this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database connection
+	 *
+	 * @param	bool	$persistent
+	 * @return	object
+	 */
+	public function db_connect($persistent = FALSE)
+	{
+		if (isset($this->stricton))
+		{
+			if ($this->stricton)
+			{
+				$sql = 'CONCAT(@@sql_mode, ",", "STRICT_ALL_TABLES")';
+			}
+			else
+			{
+				$sql = 'REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(
+                                        @@sql_mode,
+                                        "STRICT_ALL_TABLES,", ""),
+                                        ",STRICT_ALL_TABLES", ""),
+                                        "STRICT_ALL_TABLES", ""),
+                                        "STRICT_TRANS_TABLES,", ""),
+                                        ",STRICT_TRANS_TABLES", ""),
+                                        "STRICT_TRANS_TABLES", "")';
+			}
+
+			if ( ! empty($sql))
+			{
+				if (empty($this->options[PDO::MYSQL_ATTR_INIT_COMMAND]))
+				{
+					$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] = 'SET SESSION sql_mode = '.$sql;
+				}
+				else
+				{
+					$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] .= ', @@session.sql_mode = '.$sql;
+				}
+			}
+		}
+
+		if ($this->compress === TRUE)
+		{
+			$this->options[PDO::MYSQL_ATTR_COMPRESS] = TRUE;
+		}
+
+		if (is_array($this->encrypt))
+		{
+			$ssl = array();
+			empty($this->encrypt['ssl_key'])    OR $ssl[PDO::MYSQL_ATTR_SSL_KEY]    = $this->encrypt['ssl_key'];
+			empty($this->encrypt['ssl_cert'])   OR $ssl[PDO::MYSQL_ATTR_SSL_CERT]   = $this->encrypt['ssl_cert'];
+			empty($this->encrypt['ssl_ca'])     OR $ssl[PDO::MYSQL_ATTR_SSL_CA]     = $this->encrypt['ssl_ca'];
+			empty($this->encrypt['ssl_capath']) OR $ssl[PDO::MYSQL_ATTR_SSL_CAPATH] = $this->encrypt['ssl_capath'];
+			empty($this->encrypt['ssl_cipher']) OR $ssl[PDO::MYSQL_ATTR_SSL_CIPHER] = $this->encrypt['ssl_cipher'];
+
+			// DO NOT use array_merge() here!
+			// It re-indexes numeric keys and the PDO_MYSQL_ATTR_SSL_* constants are integers.
+			empty($ssl) OR $this->options += $ssl;
+		}
+
+		// Prior to version 5.7.3, MySQL silently downgrades to an unencrypted connection if SSL setup fails
+		if (
+			($pdo = parent::db_connect($persistent)) !== FALSE
+			&& ! empty($ssl)
+			&& version_compare($pdo->getAttribute(PDO::ATTR_CLIENT_VERSION), '5.7.3', '<=')
+			&& empty($pdo->query("SHOW STATUS LIKE 'ssl_cipher'")->fetchObject()->Value)
+		)
+		{
+			$message = 'PDO_MYSQL was configured for an SSL connection, but got an unencrypted connection instead!';
+			log_message('error', $message);
+			return ($this->db_debug) ? $this->display_error($message, '', TRUE) : FALSE;
+		}
+
+		return $pdo;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Select the database
+	 *
+	 * @param	string	$database
+	 * @return	bool
+	 */
+	public function db_select($database = '')
+	{
+		if ($database === '')
+		{
+			$database = $this->database;
+		}
+
+		if (FALSE !== $this->simple_query('USE '.$this->escape_identifiers($database)))
+		{
+			$this->database = $database;
+			$this->data_cache = array();
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Begin Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_begin()
+	{
+		$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, FALSE);
+		return $this->conn_id->beginTransaction();
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Commit Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_commit()
+	{
+		if ($this->conn_id->commit())
+		{
+			$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, TRUE);
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Rollback Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_rollback()
+	{
+		if ($this->conn_id->rollBack())
+		{
+			$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, TRUE);
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SHOW TABLES';
+
+		if ($prefix_limit === TRUE && $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;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'TRUNCATE '.$table;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * FROM tables
+	 *
+	 * Groups tables in FROM clauses if needed, so there is no confusion
+	 * about operator precedence.
+	 *
+	 * @return	string
+	 */
+	protected function _from_tables()
+	{
+		if ( ! empty($this->qb_join) && count($this->qb_from) > 1)
+		{
+			return '('.implode(', ', $this->qb_from).')';
+		}
+
+		return implode(', ', $this->qb_from);
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_mysql_forge.php b/system/database/drivers/pdo/subdrivers/pdo_mysql_forge.php
new file mode 100644
index 000000000..c7a92b826
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_mysql_forge.php
@@ -0,0 +1,256 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO MySQL Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_mysql_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_database	= 'CREATE DATABASE %s CHARACTER SET %s COLLATE %s';
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= 'CREATE TABLE IF NOT EXISTS';
+
+	/**
+	 * CREATE TABLE keys flag
+	 *
+	 * Whether table keys are created from within the
+	 * CREATE TABLE statement.
+	 *
+	 * @var	bool
+	 */
+	protected $_create_table_keys	= TRUE;
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= 'DROP TABLE IF EXISTS';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'TINYINT',
+		'SMALLINT',
+		'MEDIUMINT',
+		'INT',
+		'INTEGER',
+		'BIGINT',
+		'REAL',
+		'DOUBLE',
+		'DOUBLE PRECISION',
+		'FLOAT',
+		'DECIMAL',
+		'NUMERIC'
+	);
+
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null = 'NULL';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * CREATE TABLE attributes
+	 *
+	 * @param	array	$attributes	Associative array of table attributes
+	 * @return	string
+	 */
+	protected function _create_table_attr($attributes)
+	{
+		$sql = '';
+
+		foreach (array_keys($attributes) as $key)
+		{
+			if (is_string($key))
+			{
+				$sql .= ' '.strtoupper($key).' = '.$attributes[$key];
+			}
+		}
+
+		if ( ! empty($this->db->char_set) && ! strpos($sql, 'CHARACTER SET') && ! strpos($sql, 'CHARSET'))
+		{
+			$sql .= ' DEFAULT CHARACTER SET = '.$this->db->char_set;
+		}
+
+		if ( ! empty($this->db->dbcollat) && ! strpos($sql, 'COLLATE'))
+		{
+			$sql .= ' COLLATE = '.$this->db->dbcollat;
+		}
+
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if ($alter_type === 'DROP')
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			if ($field[$i]['_literal'] !== FALSE)
+			{
+				$field[$i] = ($alter_type === 'ADD')
+						? "\n\tADD ".$field[$i]['_literal']
+						: "\n\tMODIFY ".$field[$i]['_literal'];
+			}
+			else
+			{
+				if ($alter_type === 'ADD')
+				{
+					$field[$i]['_literal'] = "\n\tADD ";
+				}
+				else
+				{
+					$field[$i]['_literal'] = empty($field[$i]['new_name']) ? "\n\tMODIFY " : "\n\tCHANGE ";
+				}
+
+				$field[$i] = $field[$i]['_literal'].$this->_process_column($field[$i]);
+			}
+		}
+
+		return array($sql.implode(',', $field));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process column
+	 *
+	 * @param	array	$field
+	 * @return	string
+	 */
+	protected function _process_column($field)
+	{
+		$extra_clause = isset($field['after'])
+			? ' AFTER '.$this->db->escape_identifiers($field['after']) : '';
+
+		if (empty($extra_clause) && isset($field['first']) && $field['first'] === TRUE)
+		{
+			$extra_clause = ' FIRST';
+		}
+
+		return $this->db->escape_identifiers($field['name'])
+			.(empty($field['new_name']) ? '' : ' '.$this->db->escape_identifiers($field['new_name']))
+			.' '.$field['type'].$field['length']
+			.$field['unsigned']
+			.$field['null']
+			.$field['default']
+			.$field['auto_increment']
+			.$field['unique']
+			.(empty($field['comment']) ? '' : ' COMMENT '.$field['comment'])
+			.$extra_clause;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process indexes
+	 *
+	 * @param	string	$table	(ignored)
+	 * @return	string
+	 */
+	protected function _process_indexes($table)
+	{
+		$sql = '';
+
+		for ($i = 0, $c = count($this->keys); $i < $c; $i++)
+		{
+			if (is_array($this->keys[$i]))
+			{
+				for ($i2 = 0, $c2 = count($this->keys[$i]); $i2 < $c2; $i2++)
+				{
+					if ( ! isset($this->fields[$this->keys[$i][$i2]]))
+					{
+						unset($this->keys[$i][$i2]);
+						continue;
+					}
+				}
+			}
+			elseif ( ! isset($this->fields[$this->keys[$i]]))
+			{
+				unset($this->keys[$i]);
+				continue;
+			}
+
+			is_array($this->keys[$i]) OR $this->keys[$i] = array($this->keys[$i]);
+
+			$sql .= ",\n\tKEY ".$this->db->escape_identifiers(implode('_', $this->keys[$i]))
+				.' ('.implode(', ', $this->db->escape_identifiers($this->keys[$i])).')';
+		}
+
+		$this->keys = array();
+
+		return $sql;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php b/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php
new file mode 100644
index 000000000..abf9167d6
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php
@@ -0,0 +1,326 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Oracle 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/user_guide/database/
+ */
+class CI_DB_pdo_oci_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'oci';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * List of reserved identifiers
+	 *
+	 * Identifiers that must NOT be escaped.
+	 *
+	 * @var	string[]
+	 */
+	protected $_reserved_identifiers = array('*', 'rownum');
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('ASC', 'ASC'); // Currently not supported
+
+	/**
+	 * COUNT string
+	 *
+	 * @used-by	CI_DB_driver::count_all()
+	 * @used-by	CI_DB_query_builder::count_all_results()
+	 *
+	 * @var	string
+	 */
+	protected $_count_string = 'SELECT COUNT(1) AS ';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'oci:dbname=';
+
+			// Oracle has a slightly different PDO DSN format (Easy Connect),
+			// which also supports pre-defined DSNs.
+			if (empty($this->hostname) && empty($this->port))
+			{
+				$this->dsn .= $this->database;
+			}
+			else
+			{
+				$this->dsn .= '//'.(empty($this->hostname) ? '127.0.0.1' : $this->hostname)
+					.(empty($this->port) ? '' : ':'.$this->port).'/';
+
+				empty($this->database) OR $this->dsn .= $this->database;
+			}
+
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+		}
+		elseif ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 4) === FALSE)
+		{
+			$this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database version number
+	 *
+	 * @return	string
+	 */
+	public function version()
+	{
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		$version_string = parent::version();
+		if (preg_match('#Release\s(?<version>\d+(?:\.\d+)+)#', $version_string, $match))
+		{
+			return $this->data_cache['version'] = $match[1];
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "TABLE_NAME" FROM "ALL_TABLES"';
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			return $sql.' WHERE "TABLE_NAME" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		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 = '')
+	{
+		if (strpos($table, '.') !== FALSE)
+		{
+			sscanf($table, '%[^.].%s', $owner, $table);
+		}
+		else
+		{
+			$owner = $this->username;
+		}
+
+		return 'SELECT COLUMN_NAME FROM ALL_TAB_COLUMNS
+			WHERE UPPER(OWNER) = '.$this->escape(strtoupper($owner)).'
+				AND UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		if (strpos($table, '.') !== FALSE)
+		{
+			sscanf($table, '%[^.].%s', $owner, $table);
+		}
+		else
+		{
+			$owner = $this->username;
+		}
+
+		$sql = 'SELECT COLUMN_NAME, DATA_TYPE, CHAR_LENGTH, DATA_PRECISION, DATA_LENGTH, DATA_DEFAULT, NULLABLE
+			FROM ALL_TAB_COLUMNS
+			WHERE UPPER(OWNER) = '.$this->escape(strtoupper($owner)).'
+				AND UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+
+		if (($query = $this->query($sql)) === 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]->COLUMN_NAME;
+			$retval[$i]->type		= $query[$i]->DATA_TYPE;
+
+			$length = ($query[$i]->CHAR_LENGTH > 0)
+				? $query[$i]->CHAR_LENGTH : $query[$i]->DATA_PRECISION;
+			if ($length === NULL)
+			{
+				$length = $query[$i]->DATA_LENGTH;
+			}
+			$retval[$i]->max_length		= $length;
+
+			$default = $query[$i]->DATA_DEFAULT;
+			if ($default === NULL && $query[$i]->NULLABLE === 'N')
+			{
+				$default = '';
+			}
+			$retval[$i]->default		= $query[$i]->COLUMN_DEFAULT;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert batch statement
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return 	string
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		$keys = implode(', ', $keys);
+		$sql = "INSERT ALL\n";
+
+		for ($i = 0, $c = count($values); $i < $c; $i++)
+		{
+			$sql .= '	INTO '.$table.' ('.$keys.') VALUES '.$values[$i]."\n";
+		}
+
+		return $sql.'SELECT * FROM dual';
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		if ($this->qb_limit)
+		{
+			$this->where('rownum <= ',$this->qb_limit, FALSE);
+			$this->qb_limit = FALSE;
+		}
+
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		if (version_compare($this->version(), '12.1', '>='))
+		{
+			// OFFSET-FETCH can be used only with the ORDER BY clause
+			empty($this->qb_orderby) && $sql .= ' ORDER BY 1';
+
+			return $sql.' OFFSET '.(int) $this->qb_offset.' ROWS FETCH NEXT '.$this->qb_limit.' ROWS ONLY';
+		}
+
+		return 'SELECT * FROM (SELECT inner_query.*, rownum rnum FROM ('.$sql.') inner_query WHERE rownum < '.($this->qb_offset + $this->qb_limit + 1).')'
+			.($this->qb_offset ? ' WHERE rnum >= '.($this->qb_offset + 1): '');
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php b/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php
new file mode 100644
index 000000000..813207b8e
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php
@@ -0,0 +1,176 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO Oracle Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_oci_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_database	= FALSE;
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= FALSE;
+
+	/**
+	 * DROP DATABASE statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_database	= FALSE;
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	bool|array
+	 */
+	protected $_unsigned		= FALSE;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if ($alter_type === 'DROP')
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+		elseif ($alter_type === 'CHANGE')
+		{
+			$alter_type = 'MODIFY';
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			if ($field[$i]['_literal'] !== FALSE)
+			{
+				$field[$i] = "\n\t".$field[$i]['_literal'];
+			}
+			else
+			{
+				$field[$i]['_literal'] = "\n\t".$this->_process_column($field[$i]);
+
+				if ( ! empty($field[$i]['comment']))
+				{
+					$sqls[] = 'COMMENT ON COLUMN '
+						.$this->db->escape_identifiers($table).'.'.$this->db->escape_identifiers($field[$i]['name'])
+						.' IS '.$field[$i]['comment'];
+				}
+
+				if ($alter_type === 'MODIFY' && ! empty($field[$i]['new_name']))
+				{
+					$sqls[] = $sql.' RENAME COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+						.' TO '.$this->db->escape_identifiers($field[$i]['new_name']);
+				}
+			}
+		}
+
+		$sql .= ' '.$alter_type.' ';
+		$sql .= (count($field) === 1)
+				? $field[0]
+				: '('.implode(',', $field).')';
+
+		// RENAME COLUMN must be executed after MODIFY
+		array_unshift($sqls, $sql);
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		// Not supported - sequences and triggers must be used instead
+	}
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'NUMBER';
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'NUMBER';
+				return;
+			case 'INT':
+				$attributes['TYPE'] = 'NUMBER';
+				return;
+			case 'BIGINT':
+				$attributes['TYPE'] = 'NUMBER';
+				return;
+			default: return;
+		}
+	}
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php b/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php
new file mode 100644
index 000000000..066dd9614
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php
@@ -0,0 +1,229 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO ODBC 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/user_guide/database/
+ */
+class CI_DB_pdo_odbc_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'odbc';
+
+	/**
+	 * Database schema
+	 *
+	 * @var	string
+	 */
+	public $schema = 'public';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Identifier escape character
+	 *
+	 * Must be empty for ODBC.
+	 *
+	 * @var	string
+	 */
+	protected $_escape_char = '';
+
+	/**
+	 * ESCAPE statement string
+	 *
+	 * @var	string
+	 */
+	protected $_like_escape_str = " {escape '%s'} ";
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('RND()', 'RND(%d)');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'odbc:';
+
+			// Pre-defined DSN
+			if (empty($this->hostname) && empty($this->HOSTNAME) && empty($this->port) && empty($this->PORT))
+			{
+				if (isset($this->DSN))
+				{
+					$this->dsn .= 'DSN='.$this->DSN;
+				}
+				elseif ( ! empty($this->database))
+				{
+					$this->dsn .= 'DSN='.$this->database;
+				}
+
+				return;
+			}
+
+			// If the DSN is not pre-configured - try to build an IBM DB2 connection string
+			$this->dsn .= 'DRIVER='.(isset($this->DRIVER) ? '{'.$this->DRIVER.'}' : '{IBM DB2 ODBC DRIVER}').';';
+
+			if (isset($this->DATABASE))
+			{
+				$this->dsn .= 'DATABASE='.$this->DATABASE.';';
+			}
+			elseif ( ! empty($this->database))
+			{
+				$this->dsn .= 'DATABASE='.$this->database.';';
+			}
+
+			if (isset($this->HOSTNAME))
+			{
+				$this->dsn .= 'HOSTNAME='.$this->HOSTNAME.';';
+			}
+			else
+			{
+				$this->dsn .= 'HOSTNAME='.(empty($this->hostname) ? '127.0.0.1;' : $this->hostname.';');
+			}
+
+			if (isset($this->PORT))
+			{
+				$this->dsn .= 'PORT='.$this->port.';';
+			}
+			elseif ( ! empty($this->port))
+			{
+				$this->dsn .= ';PORT='.$this->port.';';
+			}
+
+			$this->dsn .= 'PROTOCOL='.(isset($this->PROTOCOL) ? $this->PROTOCOL.';' : 'TCPIP;');
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Platform-dependent string escape
+	 *
+	 * @param	string
+	 * @return	string
+	 */
+	protected function _escape_str($str)
+	{
+		$this->display_error('db_unsupported_feature');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Determines if a query is a "write" type.
+	 *
+	 * @param	string	An SQL query string
+	 * @return	bool
+	 */
+	public function is_write_type($sql)
+	{
+		if (preg_match('#^(INSERT|UPDATE).*RETURNING\s.+(\,\s?.+)*$#is', $sql))
+		{
+			return FALSE;
+		}
+
+		return parent::is_write_type($sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = "SELECT table_name FROM information_schema.tables WHERE table_schema = '".$this->schema."'";
+
+		if ($prefix_limit !== FALSE && $this->dbprefix !== '')
+		{
+			return $sql." AND table_name LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		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 'SELECT column_name FROM information_schema.columns WHERE table_name = '.$this->escape($table);
+	}
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_odbc_forge.php b/system/database/drivers/pdo/subdrivers/pdo_odbc_forge.php
new file mode 100644
index 000000000..a2a3bada3
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_odbc_forge.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO ODBC Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/database/
+ */
+class CI_DB_pdo_odbc_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	bool|array
+	 */
+	protected $_unsigned		= FALSE;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		// Not supported (in most databases at least)
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
new file mode 100644
index 000000000..9aed3a2fe
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
@@ -0,0 +1,384 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO PostgreSQL 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/user_guide/database/
+ */
+class CI_DB_pdo_pgsql_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'pgsql';
+
+	/**
+	 * Database schema
+	 *
+	 * @var	string
+	 */
+	public $schema = 'public';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('RANDOM()', 'RANDOM()');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'pgsql:host='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ';port='.$this->port;
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+
+			if ( ! empty($this->username))
+			{
+				$this->dsn .= ';username='.$this->username;
+				empty($this->password) OR $this->dsn .= ';password='.$this->password;
+			}
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database connection
+	 *
+	 * @param	bool	$persistent
+	 * @return	object
+	 */
+	public function db_connect($persistent = FALSE)
+	{
+		$this->conn_id = parent::db_connect($persistent);
+
+		if (is_object($this->conn_id) && ! empty($this->schema))
+		{
+			$this->simple_query('SET search_path TO '.$this->schema.',public');
+		}
+
+		return $this->conn_id;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert ID
+	 *
+	 * @param	string	$name
+	 * @return	int
+	 */
+	public function insert_id($name = NULL)
+	{
+		if ($name === NULL && version_compare($this->version(), '8.1', '>='))
+		{
+			$query = $this->query('SELECT LASTVAL() AS ins_id');
+			$query = $query->row();
+			return $query->ins_id;
+		}
+
+		return $this->conn_id->lastInsertId($name);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Determines if a query is a "write" type.
+	 *
+	 * @param	string	An SQL query string
+	 * @return	bool
+	 */
+	public function is_write_type($sql)
+	{
+		if (preg_match('#^(INSERT|UPDATE).*RETURNING\s.+(\,\s?.+)*$#is', $sql))
+		{
+			return FALSE;
+		}
+
+		return parent::is_write_type($sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * "Smart" Escape String
+	 *
+	 * Escapes data based on type
+	 *
+	 * @param	string	$str
+	 * @return	mixed
+	 */
+	public function escape($str)
+	{
+		if (is_bool($str))
+		{
+			return ($str) ? 'TRUE' : 'FALSE';
+		}
+
+		return parent::escape($str);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY
+	 *
+	 * @param	string	$orderby
+	 * @param	string	$direction	ASC, DESC or RANDOM
+	 * @param	bool	$escape
+	 * @return	object
+	 */
+	public function order_by($orderby, $direction = '', $escape = NULL)
+	{
+		$direction = strtoupper(trim($direction));
+		if ($direction === 'RANDOM')
+		{
+			if ( ! is_float($orderby) && ctype_digit((string) $orderby))
+			{
+				$orderby = ($orderby > 1)
+					? (float) '0.'.$orderby
+					: (float) $orderby;
+			}
+
+			if (is_float($orderby))
+			{
+				$this->simple_query('SET SEED '.$orderby);
+			}
+
+			$orderby = $this->_random_keyword[0];
+			$direction = '';
+			$escape = FALSE;
+		}
+
+		return parent::order_by($orderby, $direction, $escape);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "table_name" FROM "information_schema"."tables" WHERE "table_schema" = \''.$this->schema."'";
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			return $sql.' AND "table_name" LIKE \''
+				.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * List 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 'SELECT "column_name"
+			FROM "information_schema"."columns"
+			WHERE LOWER("table_name") = '.$this->escape(strtolower($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT "column_name", "data_type", "character_maximum_length", "numeric_precision", "column_default"
+			FROM "information_schema"."columns"
+			WHERE LOWER("table_name") = '.$this->escape(strtolower($table));
+
+		if (($query = $this->query($sql)) === 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]->column_name;
+			$retval[$i]->type		= $query[$i]->data_type;
+			$retval[$i]->max_length		= ($query[$i]->character_maximum_length > 0) ? $query[$i]->character_maximum_length : $query[$i]->numeric_precision;
+			$retval[$i]->default		= $query[$i]->column_default;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update_Batch statement
+	 *
+	 * Generates a platform-specific batch update string from the supplied data
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$values	Update data
+	 * @param	string	$index	WHERE key
+	 * @return	string
+	 */
+	protected function _update_batch($table, $values, $index)
+	{
+		$ids = array();
+		foreach ($values as $key => $val)
+		{
+			$ids[] = $val[$index]['value'];
+
+			foreach (array_keys($val) as $field)
+			{
+				if ($field !== $index)
+				{
+					$final[$val[$field]['field']][] = 'WHEN '.$val[$index]['value'].' THEN '.$val[$field]['value'];
+				}
+			}
+		}
+
+		$cases = '';
+		foreach ($final as $k => $v)
+		{
+			$cases .= $k.' = (CASE '.$val[$index]['field']."\n"
+				.implode("\n", $v)."\n"
+				.'ELSE '.$k.' END), ';
+		}
+
+		$this->where($val[$index]['field'].' IN('.implode(',', $ids).')', NULL, FALSE);
+
+		return 'UPDATE '.$table.' SET '.substr($cases, 0, -2).$this->_compile_wh('qb_where');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		$this->qb_limit = FALSE;
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		return $sql.' LIMIT '.$this->qb_limit.($this->qb_offset ? ' OFFSET '.$this->qb_offset : '');
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php b/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php
new file mode 100644
index 000000000..b00af4ad0
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php
@@ -0,0 +1,210 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO PostgreSQL Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_pgsql_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= 'DROP TABLE IF EXISTS';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'INT2'		=> 'INTEGER',
+		'SMALLINT'	=> 'INTEGER',
+		'INT'		=> 'BIGINT',
+		'INT4'		=> 'BIGINT',
+		'INTEGER'	=> 'BIGINT',
+		'INT8'		=> 'NUMERIC',
+		'BIGINT'	=> 'NUMERIC',
+		'REAL'		=> 'DOUBLE PRECISION',
+		'FLOAT'		=> 'DOUBLE PRECISION'
+	);
+
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null = 'NULL';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * @param	object	&$db	Database object
+	 * @return	void
+	 */
+	public function __construct(&$db)
+	{
+		parent::__construct($db);
+
+		if (version_compare($this->db->version(), '9.0', '>'))
+		{
+			$this->create_table_if = 'CREATE TABLE IF NOT EXISTS';
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+ 	{
+		if (in_array($alter_type, array('DROP', 'ADD'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			if ($field[$i]['_literal'] !== FALSE)
+			{
+				return FALSE;
+			}
+
+			if (version_compare($this->db->version(), '8', '>=') && isset($field[$i]['type']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' TYPE '.$field[$i]['type'].$field[$i]['length'];
+			}
+
+			if ( ! empty($field[$i]['default']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' SET DEFAULT '.$field[$i]['default'];
+			}
+
+			if (isset($field[$i]['null']))
+			{
+				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.($field[$i]['null'] === TRUE ? ' DROP NOT NULL' : ' SET NOT NULL');
+			}
+
+			if ( ! empty($field[$i]['new_name']))
+			{
+				$sqls[] = $sql.' RENAME COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
+					.' TO '.$this->db->escape_identifiers($field[$i]['new_name']);
+			}
+
+			if ( ! empty($field[$i]['comment']))
+			{
+				$sqls[] = 'COMMENT ON COLUMN '
+					.$this->db->escape_identifiers($table).'.'.$this->db->escape_identifiers($field[$i]['name'])
+					.' IS '.$field[$i]['comment'];
+			}
+		}
+
+		return $sqls;
+ 	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		// Reset field lengths for data types that don't support it
+		if (isset($attributes['CONSTRAINT']) && stripos($attributes['TYPE'], 'int') !== FALSE)
+		{
+			$attributes['CONSTRAINT'] = NULL;
+		}
+
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'TINYINT':
+				$attributes['TYPE'] = 'SMALLINT';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+		{
+			$field['type'] = ($field['type'] === 'NUMERIC')
+				? 'BIGSERIAL'
+				: 'SERIAL';
+		}
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlite_driver.php b/system/database/drivers/pdo/subdrivers/pdo_sqlite_driver.php
new file mode 100644
index 000000000..9b70f3ea6
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlite_driver.php
@@ -0,0 +1,219 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO SQLite 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/user_guide/database/
+ */
+class CI_DB_pdo_sqlite_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'sqlite';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('RANDOM()', 'RANDOM()');
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'sqlite:';
+
+			if (empty($this->database) && empty($this->hostname))
+			{
+				$this->database = ':memory:';
+			}
+
+			$this->database = empty($this->database) ? $this->hostname : $this->database;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT "NAME" FROM "SQLITE_MASTER" WHERE "TYPE" = \'table\'';
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			return $sql.' AND "NAME" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Fetch Field Names
+	 *
+	 * @param	string	$table	Table name
+	 * @return	array
+	 */
+	public function list_fields($table)
+	{
+		// Is there a cached result?
+		if (isset($this->data_cache['field_names'][$table]))
+		{
+			return $this->data_cache['field_names'][$table];
+		}
+
+		if (($result = $this->query('PRAGMA TABLE_INFO('.$this->protect_identifiers($table, TRUE, NULL, FALSE).')')) === FALSE)
+		{
+			return FALSE;
+		}
+
+		$this->data_cache['field_names'][$table] = array();
+		foreach ($result->result_array() as $row)
+		{
+			$this->data_cache['field_names'][$table][] = $row['name'];
+		}
+
+		return $this->data_cache['field_names'][$table];
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		if (($query = $this->query('PRAGMA TABLE_INFO('.$this->protect_identifiers($table, TRUE, NULL, FALSE).')')) === FALSE)
+		{
+			return FALSE;
+		}
+
+		$query = $query->result_array();
+		if (empty($query))
+		{
+			return FALSE;
+		}
+
+		$retval = array();
+		for ($i = 0, $c = count($query); $i < $c; $i++)
+		{
+			$retval[$i]			= new stdClass();
+			$retval[$i]->name		= $query[$i]['name'];
+			$retval[$i]->type		= $query[$i]['type'];
+			$retval[$i]->max_length		= NULL;
+			$retval[$i]->default		= $query[$i]['dflt_value'];
+			$retval[$i]->primary_key	= isset($query[$i]['pk']) ? (int) $query[$i]['pk'] : 0;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Replace statement
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return 	string
+	 */
+	protected function _replace($table, $keys, $values)
+	{
+		return 'INSERT OR '.parent::_replace($table, $keys, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the TRUNCATE statement,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'DELETE FROM '.$table;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlite_forge.php b/system/database/drivers/pdo/subdrivers/pdo_sqlite_forge.php
new file mode 100644
index 000000000..18c475b17
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlite_forge.php
@@ -0,0 +1,238 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO SQLite Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_sqlite_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= 'CREATE TABLE IF NOT EXISTS';
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= 'DROP TABLE IF EXISTS';
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	bool|array
+	 */
+	protected $_unsigned		= FALSE;
+
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null		= 'NULL';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * @param	object	&$db	Database object
+	 * @return	void
+	 */
+	public function __construct(&$db)
+	{
+		parent::__construct($db);
+
+		if (version_compare($this->db->version(), '3.3', '<'))
+		{
+			$this->_create_table_if = FALSE;
+			$this->_drop_table_if   = FALSE;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Create database
+	 *
+	 * @param	string	$db_name	(ignored)
+	 * @return	bool
+	 */
+	public function create_database($db_name)
+	{
+		// In SQLite, a database is created when you connect to the database.
+		// We'll return TRUE so that an error isn't generated
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Drop database
+	 *
+	 * @param	string	$db_name	(ignored)
+	 * @return	bool
+	 */
+	public function drop_database($db_name)
+	{
+		// In SQLite, a database is dropped when we delete a file
+		if (file_exists($this->db->database))
+		{
+			// We need to close the pseudo-connection first
+			$this->db->close();
+			if ( ! @unlink($this->db->database))
+			{
+				return $this->db->db_debug ? $this->db->display_error('db_unable_to_drop') : FALSE;
+			}
+			elseif ( ! empty($this->db->data_cache['db_names']))
+			{
+				$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+				if ($key !== FALSE)
+				{
+					unset($this->db->data_cache['db_names'][$key]);
+				}
+			}
+
+			return TRUE;
+		}
+
+		return $this->db->db_debug ? $this->db->display_error('db_unable_to_drop') : FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if ($alter_type === 'DROP' OR $alter_type === 'CHANGE')
+		{
+			// drop_column():
+			//	BEGIN TRANSACTION;
+			//	CREATE TEMPORARY TABLE t1_backup(a,b);
+			//	INSERT INTO t1_backup SELECT a,b FROM t1;
+			//	DROP TABLE t1;
+			//	CREATE TABLE t1(a,b);
+			//	INSERT INTO t1 SELECT a,b FROM t1_backup;
+			//	DROP TABLE t1_backup;
+			//	COMMIT;
+
+			return FALSE;
+		}
+
+		return parent::_alter_table($alter_type, $table, $field);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Process column
+	 *
+	 * @param	array	$field
+	 * @return	string
+	 */
+	protected function _process_column($field)
+	{
+		return $this->db->escape_identifiers($field['name'])
+			.' '.$field['type']
+			.$field['auto_increment']
+			.$field['null']
+			.$field['unique']
+			.$field['default'];
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'ENUM':
+			case 'SET':
+				$attributes['TYPE'] = 'TEXT';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE && stripos($field['type'], 'int') !== FALSE)
+		{
+			$field['type'] = 'INTEGER PRIMARY KEY';
+			$field['default'] = '';
+			$field['null'] = '';
+			$field['unique'] = '';
+			$field['auto_increment'] = ' AUTOINCREMENT';
+
+			$this->primary_keys = array();
+		}
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
new file mode 100644
index 000000000..07c429eec
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
@@ -0,0 +1,369 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO SQLSRV 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/user_guide/database/
+ */
+class CI_DB_pdo_sqlsrv_driver extends CI_DB_pdo_driver {
+
+	/**
+	 * Sub-driver
+	 *
+	 * @var	string
+	 */
+	public $subdriver = 'sqlsrv';
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ORDER BY random keyword
+	 *
+	 * @var	array
+	 */
+	protected $_random_keyword = array('NEWID()', 'RAND(%d)');
+
+	/**
+	 * Quoted identifier flag
+	 *
+	 * Whether to use SQL-92 standard quoted identifier
+	 * (double quotes) or brackets for identifier escaping.
+	 *
+	 * @var	bool
+	 */
+	protected $_quoted_identifier;
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array	$params
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = 'sqlsrv:Server='.(empty($this->hostname) ? '127.0.0.1' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ','.$this->port;
+			empty($this->database) OR $this->dsn .= ';Database='.$this->database;
+
+			// Some custom options
+
+			if (isset($this->QuotedId))
+			{
+				$this->dsn .= ';QuotedId='.$this->QuotedId;
+				$this->_quoted_identifier = (bool) $this->QuotedId;
+			}
+
+			if (isset($this->ConnectionPooling))
+			{
+				$this->dsn .= ';ConnectionPooling='.$this->ConnectionPooling;
+			}
+
+			if ($this->encrypt === TRUE)
+			{
+				$this->dsn .= ';Encrypt=1';
+			}
+
+			if (isset($this->TraceOn))
+			{
+				$this->dsn .= ';TraceOn='.$this->TraceOn;
+			}
+
+			if (isset($this->TrustServerCertificate))
+			{
+				$this->dsn .= ';TrustServerCertificate='.$this->TrustServerCertificate;
+			}
+
+			empty($this->APP) OR $this->dsn .= ';APP='.$this->APP;
+			empty($this->Failover_Partner) OR $this->dsn .= ';Failover_Partner='.$this->Failover_Partner;
+			empty($this->LoginTimeout) OR $this->dsn .= ';LoginTimeout='.$this->LoginTimeout;
+			empty($this->MultipleActiveResultSets) OR $this->dsn .= ';MultipleActiveResultSets='.$this->MultipleActiveResultSets;
+			empty($this->TraceFile) OR $this->dsn .= ';TraceFile='.$this->TraceFile;
+			empty($this->WSID) OR $this->dsn .= ';WSID='.$this->WSID;
+		}
+		elseif (preg_match('/QuotedId=(0|1)/', $this->dsn, $match))
+		{
+			$this->_quoted_identifier = (bool) $match[1];
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database connection
+	 *
+	 * @param	bool	$persistent
+	 * @return	object
+	 */
+	public function db_connect($persistent = FALSE)
+	{
+		if ( ! empty($this->char_set) && preg_match('/utf[^8]*8/i', $this->char_set))
+		{
+			$this->options[PDO::SQLSRV_ENCODING_UTF8] = 1;
+		}
+
+		$this->conn_id = parent::db_connect($persistent);
+
+		if ( ! is_object($this->conn_id) OR is_bool($this->_quoted_identifier))
+		{
+			return $this->conn_id;
+		}
+
+		// Determine how identifiers are escaped
+		$query = $this->query('SELECT CASE WHEN (@@OPTIONS | 256) = @@OPTIONS THEN 1 ELSE 0 END AS qi');
+		$query = $query->row_array();
+		$this->_quoted_identifier = empty($query) ? FALSE : (bool) $query['qi'];
+		$this->_escape_char = ($this->_quoted_identifier) ? '"' : array('[', ']');
+
+		return $this->conn_id;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show 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)
+	{
+		$sql = 'SELECT '.$this->escape_identifiers('name')
+			.' FROM '.$this->escape_identifiers('sysobjects')
+			.' WHERE '.$this->escape_identifiers('type')." = 'U'";
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' AND '.$this->escape_identifiers('name')." LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+
+		return $sql.' ORDER BY '.$this->escape_identifiers('name');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * 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 'SELECT COLUMN_NAME
+			FROM INFORMATION_SCHEMA.Columns
+			WHERE UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Returns an object with field data
+	 *
+	 * @param	string	$table
+	 * @return	array
+	 */
+	public function field_data($table)
+	{
+		$sql = 'SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, COLUMN_DEFAULT
+			FROM INFORMATION_SCHEMA.Columns
+			WHERE UPPER(TABLE_NAME) = '.$this->escape(strtoupper($table));
+
+		if (($query = $this->query($sql)) === 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]->COLUMN_NAME;
+			$retval[$i]->type		= $query[$i]->DATA_TYPE;
+			$retval[$i]->max_length		= ($query[$i]->CHARACTER_MAXIMUM_LENGTH > 0) ? $query[$i]->CHARACTER_MAXIMUM_LENGTH : $query[$i]->NUMERIC_PRECISION;
+			$retval[$i]->default		= $query[$i]->COLUMN_DEFAULT;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @param	array	$values
+	 * @return	string
+	 */
+	protected function _update($table, $values)
+	{
+		$this->qb_limit = FALSE;
+		$this->qb_orderby = array();
+		return parent::_update($table, $values);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	$table
+	 * @return	string
+	 */
+	protected function _delete($table)
+	{
+		if ($this->qb_limit)
+		{
+			return 'WITH ci_delete AS (SELECT TOP '.$this->qb_limit.' * FROM '.$table.$this->_compile_wh('qb_where').') DELETE FROM ci_delete';
+		}
+
+		return parent::_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * LIMIT
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	$sql	SQL Query
+	 * @return	string
+	 */
+	protected function _limit($sql)
+	{
+		// As of SQL Server 2012 (11.0.*) OFFSET is supported
+		if (version_compare($this->version(), '11', '>='))
+		{
+			// SQL Server OFFSET-FETCH can be used only with the ORDER BY clause
+			empty($this->qb_orderby) && $sql .= ' ORDER BY 1';
+
+			return $sql.' OFFSET '.(int) $this->qb_offset.' ROWS FETCH NEXT '.$this->qb_limit.' ROWS ONLY';
+		}
+
+		$limit = $this->qb_offset + $this->qb_limit;
+
+		// An ORDER BY clause is required for ROW_NUMBER() to work
+		if ($this->qb_offset && ! empty($this->qb_orderby))
+		{
+			$orderby = $this->_compile_order_by();
+
+			// We have to strip the ORDER BY clause
+			$sql = trim(substr($sql, 0, strrpos($sql, $orderby)));
+
+			// Get the fields to select from our subquery, so that we can avoid CI_rownum appearing in the actual results
+			if (count($this->qb_select) === 0)
+			{
+				$select = '*'; // Inevitable
+			}
+			else
+			{
+				// Use only field names and their aliases, everything else is out of our scope.
+				$select = array();
+				$field_regexp = ($this->_quoted_identifier)
+					? '("[^\"]+")' : '(\[[^\]]+\])';
+				for ($i = 0, $c = count($this->qb_select); $i < $c; $i++)
+				{
+					$select[] = preg_match('/(?:\s|\.)'.$field_regexp.'$/i', $this->qb_select[$i], $m)
+						? $m[1] : $this->qb_select[$i];
+				}
+				$select = implode(', ', $select);
+			}
+
+			return 'SELECT '.$select." FROM (\n\n"
+				.preg_replace('/^(SELECT( DISTINCT)?)/i', '\\1 ROW_NUMBER() OVER('.trim($orderby).') AS '.$this->escape_identifiers('CI_rownum').', ', $sql)
+				."\n\n) ".$this->escape_identifiers('CI_subquery')
+				."\nWHERE ".$this->escape_identifiers('CI_rownum').' BETWEEN '.($this->qb_offset + 1).' AND '.$limit;
+		}
+
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$limit.' ', $sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert batch statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data.
+	 *
+	 * @param	string	$table	Table name
+	 * @param	array	$keys	INSERT keys
+	 * @param	array	$values	INSERT values
+	 * @return	string|bool
+	 */
+	protected function _insert_batch($table, $keys, $values)
+	{
+		// Multiple-value inserts are only supported as of SQL Server 2008
+		if (version_compare($this->version(), '10', '>='))
+		{
+			return parent::_insert_batch($table, $keys, $values);
+		}
+
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
+	}
+
+}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_forge.php b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_forge.php
new file mode 100644
index 000000000..82a0d515d
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_forge.php
@@ -0,0 +1,149 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
+ *
+ * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
+ * @license	http://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 3.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PDO SQLSRV Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_sqlsrv_forge extends CI_DB_pdo_forge {
+
+	/**
+	 * CREATE TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_create_table_if	= "IF NOT EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nCREATE TABLE";
+
+	/**
+	 * DROP TABLE IF statement
+	 *
+	 * @var	string
+	 */
+	protected $_drop_table_if	= "IF EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nDROP TABLE";
+
+	/**
+	 * UNSIGNED support
+	 *
+	 * @var	array
+	 */
+	protected $_unsigned		= array(
+		'TINYINT'	=> 'SMALLINT',
+		'SMALLINT'	=> 'INT',
+		'INT'		=> 'BIGINT',
+		'REAL'		=> 'FLOAT'
+	);
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * ALTER TABLE
+	 *
+	 * @param	string	$alter_type	ALTER type
+	 * @param	string	$table		Table name
+	 * @param	mixed	$field		Column definition
+	 * @return	string|string[]
+	 */
+	protected function _alter_table($alter_type, $table, $field)
+	{
+		if (in_array($alter_type, array('ADD', 'DROP'), TRUE))
+		{
+			return parent::_alter_table($alter_type, $table, $field);
+		}
+
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' ALTER COLUMN ';
+		$sqls = array();
+		for ($i = 0, $c = count($field); $i < $c; $i++)
+		{
+			$sqls[] = $sql.$this->_process_column($field[$i]);
+		}
+
+		return $sqls;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute TYPE
+	 *
+	 * Performs a data type mapping between different databases.
+	 *
+	 * @param	array	&$attributes
+	 * @return	void
+	 */
+	protected function _attr_type(&$attributes)
+	{
+		if (isset($attributes['CONSTRAINT']) && strpos($attributes['TYPE'], 'INT') !== FALSE)
+		{
+			unset($attributes['CONSTRAINT']);
+		}
+
+		switch (strtoupper($attributes['TYPE']))
+		{
+			case 'MEDIUMINT':
+				$attributes['TYPE'] = 'INTEGER';
+				$attributes['UNSIGNED'] = FALSE;
+				return;
+			case 'INTEGER':
+				$attributes['TYPE'] = 'INT';
+				return;
+			default: return;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field attribute AUTO_INCREMENT
+	 *
+	 * @param	array	&$attributes
+	 * @param	array	&$field
+	 * @return	void
+	 */
+	protected function _attr_auto_increment(&$attributes, &$field)
+	{
+		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE && stripos($field['type'], 'int') !== FALSE)
+		{
+			$field['auto_increment'] = ' IDENTITY(1,1)';
+		}
+	}
+
+}
author	Florian Pritz <bluewind@xinu.at>	2017-09-26 13:46:14 +0200
committer	Florian Pritz <bluewind@xinu.at>	2017-09-26 13:46:14 +0200
commit	3ff6ffa3341c876b741feb66552cdd110b67872e (patch)
tree	69e11cd0009ddd1346f2dc4cd8c47244368db28e /system/database/drivers/pdo
parent	bc2f7f596f727e204e8b8c5b849545745b3cbfaa (diff)
parent	81a4c8c630ef59cffea0c24e64fb6fa7f09bfcf6 (diff)