Merge upstream branch

19 files changed, 849 insertions, 1025 deletions

diff --git a/system/database/drivers/cubrid/cubrid_driver.php b/system/database/drivers/cubrid/cubrid_driver.php
index cde719eae..42f08fbf6 100644
--- a/system/database/drivers/cubrid/cubrid_driver.php
+++ b/system/database/drivers/cubrid/cubrid_driver.php
@@ -156,24 +156,6 @@ class CI_DB_cubrid_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Set client character set
-	 *
-	 * @access	public
-	 * @param	string
-	 * @param	string
-	 * @return	resource
-	 */
-	function db_set_charset($charset, $collation)
-	{
-		// In CUBRID, there is no need to set charset or collation.
-		// This is why returning true will allow the application continue
-		// its normal process.
-		return TRUE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Version number query string
 	 *
 	 * @access	public
@@ -362,12 +344,11 @@ class CI_DB_cubrid_driver extends CI_DB {
 	/**
 	 * Affected Rows
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function affected_rows()
+	public function affected_rows()
 	{
-		return @cubrid_affected_rows($this->conn_id);
+		return @cubrid_affected_rows();
 	}
 
 	// --------------------------------------------------------------------
@@ -801,4 +782,4 @@ class CI_DB_cubrid_driver extends CI_DB {
 
 
 /* End of file cubrid_driver.php */
-/* Location: ./system/database/drivers/cubrid/cubrid_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/cubrid/cubrid_driver.php */
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index 2a1098932..2a4f2b575 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -114,30 +114,25 @@ class CI_DB_mssql_driver extends CI_DB {
 	/**
 	 * Select the database
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @param	string	database name
+	 * @return	bool
 	 */
-	function db_select()
+	public function db_select($database = '')
 	{
+		if ($database === '')
+		{
+			$database = $this->database;
+		}
+
 		// Note: The brackets are required in the event that the DB name
 		// contains reserved characters
-		return @mssql_select_db('['.$this->database.']', $this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
+		if (@mssql_select_db('['.$database.']', $this->conn_id))
+		{
+			$this->database = $database;
+			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;
+		return FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -676,4 +671,4 @@ class CI_DB_mssql_driver extends CI_DB {
 
 
 /* End of file mssql_driver.php */
-/* Location: ./system/database/drivers/mssql/mssql_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mssql/mssql_driver.php */
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index 0f69a0723..c88a8a766 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQL Database Adapter Class
  *
@@ -42,46 +40,47 @@
  */
 class CI_DB_mysql_driver extends CI_DB {
 
-	var $dbdriver = 'mysql';
+	public $dbdriver = 'mysql';
 
 	// The character used for escaping
-	var	$_escape_char = '`';
+	protected $_escape_char = '`';
 
 	// clause and character used for LIKE escape sequences - not used in MySQL
-	var $_like_escape_str = '';
-	var $_like_escape_chr = '';
-
-	/**
-	 * Whether to use the MySQL "delete hack" which allows the number
-	 * of affected rows to be shown. Uses a preg_replace when enabled,
-	 * adding a bit more processing to all queries.
-	 */
-	var $delete_hack = TRUE;
+	protected $_like_escape_str = '';
+	protected $_like_escape_chr = '';
 
 	/**
 	 * The syntax to count rows is slightly different across different
 	 * database engines, so this string appears in each driver and is
 	 * used for the count_all() and count_all_results() functions.
 	 */
-	var $_count_string = 'SELECT COUNT(*) AS ';
-	var $_random_keyword = ' RAND()'; // database specific random keyword
-
-	// whether SET NAMES must be used to set the character set
-	var $use_set_names;
+	protected $_count_string = 'SELECT COUNT(*) AS ';
+	protected $_random_keyword = ' RAND()'; // database specific random keyword
 
 	/**
-	 * Non-persistent database connection
-	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * Whether to use the MySQL "delete hack" which allows the number
+	 * of affected rows to be shown. Uses a preg_replace when enabled,
+	 * adding a bit more processing to all queries.
 	 */
-	function db_connect()
+	public $delete_hack = TRUE;
+
+	public function __construct($params)
 	{
+		parent::__construct($params);
+
 		if ($this->port != '')
 		{
 			$this->hostname .= ':'.$this->port;
 		}
+	}
 
+	/**
+	 * Non-persistent database connection
+	 *
+	 * @return	resource
+	 */
+	public function db_connect()
+	{
 		return @mysql_connect($this->hostname, $this->username, $this->password, TRUE);
 	}
 
@@ -90,16 +89,10 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Persistent database connection
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_pconnect()
+	public function db_pconnect()
 	{
-		if ($this->port != '')
-		{
-			$this->hostname .= ':'.$this->port;
-		}
-
 		return @mysql_pconnect($this->hostname, $this->username, $this->password);
 	}
 
@@ -111,10 +104,9 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * Keep / reestablish the db connection if no queries have been
 	 * sent for a length of time exceeding the server's idle timeout
 	 *
-	 * @access	public
 	 * @return	void
 	 */
-	function reconnect()
+	public function reconnect()
 	{
 		if (mysql_ping($this->conn_id) === FALSE)
 		{
@@ -127,12 +119,23 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Select the database
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @param	string	database name
+	 * @return	bool
 	 */
-	function db_select()
+	public function db_select($database = '')
 	{
-		return @mysql_select_db($this->database, $this->conn_id);
+		if ($database === '')
+		{
+			$database = $this->database;
+		}
+
+		if (@mysql_select_db($database, $this->conn_id))
+		{
+			$this->database = $database;
+			return TRUE;
+		}
+
+		return FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -140,12 +143,11 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Set client character set
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	string
-	 * @return	resource
+	 * @return	bool
 	 */
-	function db_set_charset($charset, $collation)
+	public function db_set_charset($charset, $collation)
 	{
 		return function_exists('mysql_set_charset')
 			? @mysql_set_charset($charset, $this->conn_id)
@@ -157,12 +159,11 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Version number query string
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function _version()
+	protected function _version()
 	{
-		return "SELECT version() AS ver";
+		return 'SELECT version() AS ver';
 	}
 
 	// --------------------------------------------------------------------
@@ -170,14 +171,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Execute the query
 	 *
-	 * @access	private called by the base class
 	 * @param	string	an SQL query
-	 * @return	resource
+	 * @return	mixed
 	 */
-	function _execute($sql)
+	protected function _execute($sql)
 	{
-		$sql = $this->_prep_query($sql);
-		return @mysql_query($sql, $this->conn_id);
+		return @mysql_query($this->_prep_query($sql), $this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -187,20 +186,16 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * 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($sql)
+	protected function _prep_query($sql)
 	{
-		// "DELETE FROM TABLE" returns 0 affected rows This hack modifies
-		// the query so that it returns the number of affected rows
-		if ($this->delete_hack === TRUE)
+		// mysql_affected_rows() returns 0 for "DELETE FROM TABLE" queries. This hack
+		// modifies the query so that it a proper number of affected rows is returned.
+		if ($this->delete_hack === TRUE && preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $sql))
 		{
-			if (preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $sql))
-			{
-				$sql = preg_replace("/^\s*DELETE\s+FROM\s+(\S+)\s*$/", "DELETE FROM \\1 WHERE 1=1", $sql);
-			}
+			return preg_replace('/^\s*DELETE\s+FROM\s+(\S+)\s*$/', 'DELETE FROM \\1 WHERE 1=1', $sql);
 		}
 
 		return $sql;
@@ -211,18 +206,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Begin Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_begin($test_mode = FALSE)
+	public function trans_begin($test_mode = FALSE)
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -230,7 +219,7 @@ class CI_DB_mysql_driver extends CI_DB {
 		// Reset the transaction failure flag.
 		// If the $test_mode flag is set to TRUE transactions will be rolled back
 		// even if the queries produce a successful result.
-		$this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;
+		$this->_trans_failure = ($test_mode === TRUE);
 
 		$this->simple_query('SET AUTOCOMMIT=0');
 		$this->simple_query('START TRANSACTION'); // can also be BEGIN or BEGIN WORK
@@ -242,18 +231,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Commit Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_commit()
+	public function trans_commit()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -268,18 +251,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Rollback Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_rollback()
+	public function trans_rollback()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -294,12 +271,11 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Escape String
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	bool	whether or not the string will be used in a LIKE condition
 	 * @return	string
 	 */
-	function escape_str($str, $like = FALSE)
+	public function escape_str($str, $like = FALSE)
 	{
 		if (is_array($str))
 		{
@@ -311,7 +287,7 @@ class CI_DB_mysql_driver extends CI_DB {
 	   		return $str;
 	   	}
 
-		if (function_exists('mysql_real_escape_string') AND is_resource($this->conn_id))
+		if (function_exists('mysql_real_escape_string') && is_resource($this->conn_id))
 		{
 			$str = mysql_real_escape_string($str, $this->conn_id);
 		}
@@ -327,7 +303,7 @@ class CI_DB_mysql_driver extends CI_DB {
 		// escape LIKE condition wildcards
 		if ($like === TRUE)
 		{
-			$str = str_replace(array('%', '_'), array('\\%', '\\_'), $str);
+			return str_replace(array('%', '_'), array('\\%', '\\_'), $str);
 		}
 
 		return $str;
@@ -338,10 +314,9 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Affected Rows
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function affected_rows()
+	public function affected_rows()
 	{
 		return @mysql_affected_rows($this->conn_id);
 	}
@@ -351,10 +326,9 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Insert ID
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function insert_id()
+	public function insert_id()
 	{
 		return @mysql_insert_id($this->conn_id);
 	}
@@ -367,27 +341,25 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * Generates a platform-specific query string that counts all records in
 	 * the specified database
 	 *
-	 * @access	public
 	 * @param	string
 	 * @return	string
 	 */
-	function count_all($table = '')
+	public function count_all($table = '')
 	{
 		if ($table == '')
 		{
 			return 0;
 		}
 
-		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
-
+		$query = $this->query($this->_count_string.$this->protect_identifiers('numrows').' FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE));
 		if ($query->num_rows() == 0)
 		{
 			return 0;
 		}
 
-		$row = $query->row();
+		$query = $query->row();
 		$this->_reset_select();
-		return (int) $row->numrows;
+		return (int) $query->numrows;
 	}
 
 	// --------------------------------------------------------------------
@@ -397,17 +369,16 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
 	 *
-	 * @access	private
-	 * @param	boolean
+	 * @param	bool
 	 * @return	string
 	 */
-	function _list_tables($prefix_limit = FALSE)
+	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SHOW TABLES FROM ".$this->_escape_char.$this->database.$this->_escape_char;
+		$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
 
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		if ($prefix_limit !== FALSE && $this->dbprefix != '')
 		{
-			$sql .= " LIKE '".$this->escape_like_str($this->dbprefix)."%'";
+			return $sql." LIKE '".$this->escape_like_str($this->dbprefix)."%'";
 		}
 
 		return $sql;
@@ -420,13 +391,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the column names can be fetched
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _list_columns($table = '')
+	public function _list_columns($table = '')
 	{
-		return "SHOW COLUMNS FROM ".$this->_protect_identifiers($table, TRUE, NULL, FALSE);
+		return 'SHOW COLUMNS FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE);
 	}
 
 	// --------------------------------------------------------------------
@@ -436,13 +406,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query so that the column data can be retrieved
 	 *
-	 * @access	public
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _field_data($table)
+	public function _field_data($table)
 	{
-		return "DESCRIBE ".$table;
+		return 'DESCRIBE '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -450,10 +419,9 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * The error message string
 	 *
-	 * @access	private
 	 * @return	string
 	 */
-	function _error_message()
+	protected function _error_message()
 	{
 		return mysql_error($this->conn_id);
 	}
@@ -463,10 +431,9 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * The error message number
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	int
 	 */
-	function _error_number()
+	protected function _error_number()
 	{
 		return mysql_errno($this->conn_id);
 	}
@@ -478,11 +445,10 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * This function escapes column and table names
 	 *
-	 * @access	private
 	 * @param	string
 	 * @return	string
 	 */
-	function _escape_identifiers($item)
+	public function _escape_identifiers($item)
 	{
 		if ($this->_escape_char == '')
 		{
@@ -493,24 +459,20 @@ class CI_DB_mysql_driver extends CI_DB {
 		{
 			if (strpos($item, '.'.$id) !== FALSE)
 			{
-				$str = $this->_escape_char. str_replace('.', $this->_escape_char.'.', $item);
+				$item = str_replace('.', $this->_escape_char.'.', $item);
 
 				// remove duplicates if the user already included the escape
-				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item);
 			}
 		}
 
 		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;
+			$item = str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item);
 		}
 
 		// remove duplicates if the user already included the escape
-		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item.$this->_escape_char);
 	}
 
 	// --------------------------------------------------------------------
@@ -521,11 +483,10 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * This function implicitly groups FROM tables so there is no confusion
 	 * about operator precedence in harmony with SQL standards
 	 *
-	 * @access	public
-	 * @param	type
-	 * @return	type
+	 * @param	string	table name
+	 * @return	string
 	 */
-	function _from_tables($tables)
+	protected function _from_tables($tables)
 	{
 		if ( ! is_array($tables))
 		{
@@ -542,15 +503,14 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific insert string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the insert keys
 	 * @param	array	the insert values
 	 * @return	string
 	 */
-	function _insert($table, $keys, $values)
+	protected function _insert($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+		return 'INSERT INTO '.$table.' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -561,15 +521,14 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific replace 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 _replace($table, $keys, $values)
+	protected function _replace($table, $keys, $values)
 	{
-		return "REPLACE INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+		return 'REPLACE INTO '.$table.' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -579,15 +538,14 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * 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_batch($table, $keys, $values)
+	protected function _insert_batch($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES ".implode(', ', $values);
+		return 'INSERT INTO '.$table.' ('.implode(', ', $keys).') VALUES '.implode(', ', $values);
 	}
 
 	// --------------------------------------------------------------------
@@ -598,7 +556,6 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the update data
 	 * @param	array	the where clause
@@ -606,34 +563,22 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * @param	array	the limit clause
 	 * @return	string
 	 */
-	function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
+	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
 	{
 		foreach ($values as $key => $val)
 		{
-			$valstr[] = $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(" ", $where) : '';
-		
-		if (count($like) > 0) 
+		$where = ($where != '' && count($where) > 0) ? ' WHERE '.implode(' ', $where) : '';
+		if (count($like) > 0)
 		{
-			$sql .= ($where == '' AND count($where) <1) ? " WHERE " : ' AND ';
-			
-			foreach ($like as $st_like) 
-			{
-				$sql .= " " . $st_like;	
-			}
+			$where .= ($where == '' ? ' WHERE ' : ' AND ').implode(' ', $like);
 		}
 
-		$sql .= $orderby.$limit;
-
-		return $sql;
+		return 'UPDATE '.$table.' SET '.implode(', ', $valstr).$where
+			.(count($orderby) > 0 ? ' ORDER BY '.implode(', ', $orderby) : '')
+			.( ! $limit ? '' : ' LIMIT '.$limit);
 	}
 
 	// --------------------------------------------------------------------
@@ -644,17 +589,14 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the update data
 	 * @param	array	the where clause
 	 * @return	string
 	 */
-	function _update_batch($table, $values, $index, $where = NULL)
+	protected function _update_batch($table, $values, $index, $where = NULL)
 	{
 		$ids = array();
-		$where = ($where != '' AND count($where) >=1) ? implode(" ", $where).' AND ' : '';
-
 		foreach ($values as $key => $val)
 		{
 			$ids[] = $val[$index];
@@ -668,30 +610,21 @@ class CI_DB_mysql_driver extends CI_DB {
 			}
 		}
 
-		$sql = "UPDATE ".$table." SET ";
 		$cases = '';
-
 		foreach ($final as $k => $v)
 		{
-			$cases .= $k.' = CASE '."\n";
-			foreach ($v as $row)
-			{
-				$cases .= $row."\n";
-			}
-
-			$cases .= 'ELSE '.$k.' END, ';
+			$cases .= $k." = CASE \n"
+				.implode("\n", $v)."\n"
+				.'ELSE '.$k.' END, ';
 		}
 
-		$sql .= substr($cases, 0, -2);
-
-		$sql .= ' WHERE '.$where.$index.' IN ('.implode(',', $ids).')';
-
-		return $sql;
+		return 'UPDATE '.$table.' SET '.substr($cases, 0, -2)
+			.' WHERE '.(($where != '' && count($where) > 0) ? implode(' ', $where).' AND ' : '')
+			.$index.' IN('.implode(',', $ids).')';
 	}
 
 	// --------------------------------------------------------------------
 
-
 	/**
 	 * Truncate statement
 	 *
@@ -699,13 +632,12 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * 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($table)
+	protected function _truncate($table)
 	{
-		return "TRUNCATE ".$table;
+		return 'TRUNCATE '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -715,31 +647,27 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * 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(), $limit = FALSE)
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
 	{
 		$conditions = '';
 
 		if (count($where) > 0 OR count($like) > 0)
 		{
-			$conditions = "\nWHERE ";
-			$conditions .= implode("\n", $this->ar_where);
+			$conditions = "\nWHERE ".implode("\n", $this->ar_where);
 
 			if (count($where) > 0 && count($like) > 0)
 			{
-				$conditions .= " AND ";
+				$conditions .= ' AND ';
 			}
 			$conditions .= implode("\n", $like);
 		}
 
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
-
-		return "DELETE FROM ".$table.$conditions.$limit;
+		return 'DELETE FROM '.$table.$conditions.( ! $limit ? '' : ' LIMIT '.$limit);
 	}
 
 	// --------------------------------------------------------------------
@@ -749,24 +677,14 @@ class CI_DB_mysql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific LIMIT clause
 	 *
-	 * @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	int	the number of rows to limit the query to
+	 * @param	int	the offset value
 	 * @return	string
 	 */
-	function _limit($sql, $limit, $offset)
+	protected function _limit($sql, $limit, $offset)
 	{
-		if ($offset == 0)
-		{
-			$offset = '';
-		}
-		else
-		{
-			$offset .= ", ";
-		}
-
-		return $sql."LIMIT ".$offset.$limit;
+		return $sql.' LIMIT '.($offset == 0 ? '' : $offset.', ').$limit;
 	}
 
 	// --------------------------------------------------------------------
@@ -774,17 +692,15 @@ class CI_DB_mysql_driver extends CI_DB {
 	/**
 	 * Close DB Connection
 	 *
-	 * @access	public
 	 * @param	resource
 	 * @return	void
 	 */
-	function _close($conn_id)
+	protected function _close($conn_id)
 	{
 		@mysql_close($conn_id);
 	}
 
 }
 
-
 /* End of file mysql_driver.php */
-/* Location: ./system/database/drivers/mysql/mysql_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysql/mysql_driver.php */
diff --git a/system/database/drivers/mysql/mysql_forge.php b/system/database/drivers/mysql/mysql_forge.php
index a41a7b446..0f251b086 100644
--- a/system/database/drivers/mysql/mysql_forge.php
+++ b/system/database/drivers/mysql/mysql_forge.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQL Forge Class
  *
@@ -39,13 +37,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	/**
 	 * Create database
 	 *
-	 * @access	private
 	 * @param	string	the database name
-	 * @return	bool
+	 * @return	string
 	 */
-	function _create_database($name)
+	public function _create_database($name)
 	{
-		return "CREATE DATABASE ".$name;
+		return 'CREATE DATABASE '.$name;
 	}
 
 	// --------------------------------------------------------------------
@@ -53,13 +50,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	/**
 	 * Drop database
 	 *
-	 * @access	private
 	 * @param	string	the database name
-	 * @return	bool
+	 * @return	string
 	 */
-	function _drop_database($name)
+	public function _drop_database($name)
 	{
-		return "DROP DATABASE ".$name;
+		return 'DROP DATABASE '.$name;
 	}
 
 	// --------------------------------------------------------------------
@@ -67,83 +63,57 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	/**
 	 * Process Fields
 	 *
-	 * @access	private
 	 * @param	mixed	the fields
 	 * @return	string
 	 */
-	function _process_fields($fields)
+	private function _process_fields($fields)
 	{
 		$current_field_count = 0;
 		$sql = '';
 
-		foreach ($fields as $field=>$attributes)
+		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";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->_protect_identifiers($field);
-
-				if (array_key_exists('NAME', $attributes))
-				{
-					$sql .= ' '.$this->db->_protect_identifiers($attributes['NAME']).' ';
-				}
+				$sql .= "\n\t".$this->db->protect_identifiers($field)
+					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '');
 
-				if (array_key_exists('TYPE', $attributes))
+				if ( ! empty($attributes['TYPE']))
 				{
 					$sql .=  ' '.$attributes['TYPE'];
 
-					if (array_key_exists('CONSTRAINT', $attributes))
+					if ( ! empty($attributes['CONSTRAINT']))
 					{
-						switch ($attributes['TYPE'])
+						switch (strtolower($attributes['TYPE']))
 						{
 							case 'decimal':
 							case 'float':
 							case 'numeric':
 								$sql .= '('.implode(',', $attributes['CONSTRAINT']).')';
-							break;
-
+								break;
 							case 'enum':
 							case 'set':
 								$sql .= '("'.implode('","', $attributes['CONSTRAINT']).'")';
-							break;
-
+								break;
 							default:
 								$sql .= '('.$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';
-				}
+				$sql .= (( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
+					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
+					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
+					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
 			}
 
 			// don't add a comma on the end of the last field
@@ -161,15 +131,14 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	/**
 	 * Create Table
 	 *
-	 * @access	private
 	 * @param	string	the table name
 	 * @param	mixed	the fields
 	 * @param	mixed	primary key(s)
 	 * @param	mixed	key(s)
-	 * @param	boolean	should 'IF NOT EXISTS' be added to the SQL
+	 * @param	bool	should 'IF NOT EXISTS' be added to the SQL
 	 * @return	bool
 	 */
-	function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
+	public function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
 	{
 		$sql = 'CREATE TABLE ';
 
@@ -178,15 +147,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= $this->db->_escape_identifiers($table)." (";
-
-		$sql .= $this->_process_fields($fields);
+		$sql .= $this->db->protect_identifiers($table).' ('.$this->_process_fields($fields);
 
 		if (count($primary_keys) > 0)
 		{
 			$key_name = $this->db->_protect_identifiers(implode('_', $primary_keys));
-			$primary_keys = $this->db->_protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY ".$key_name." (" . implode(', ', $primary_keys) . ")";
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -204,13 +170,11 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 					$key = array($key_name);
 				}
 
-				$sql .= ",\n\tKEY {$key_name} (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tKEY ".$key_name.' ('.implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n) DEFAULT CHARACTER SET {$this->db->char_set} COLLATE {$this->db->dbcollat};";
-
-		return $sql;
+		return $sql."\n) DEFAULT CHARACTER SET ".$this->db->char_set.' COLLATE '.$this->db->dbcollat.';';
 	}
 
 	// --------------------------------------------------------------------
@@ -218,12 +182,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	/**
 	 * Drop Table
 	 *
-	 * @access	private
+	 * @param	string	table name
 	 * @return	string
 	 */
-	function _drop_table($table)
+	public function _drop_table($table)
 	{
-		return "DROP TABLE IF EXISTS ".$this->db->_escape_identifiers($table);
+		return 'DROP TABLE IF EXISTS '.$this->db->protect_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -232,33 +196,26 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	 * Alter table query
 	 *
 	 * Generates a platform-specific query so that a table can be altered
-	 * Called by add_column(), drop_column(), and column_alter(),
+	 * 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	array	fields
 	 * @param	string	the field after which we should add the new field
-	 * @return	object
+	 * @return	string
 	 */
-	function _alter_table($alter_type, $table, $fields, $after_field = '')
+	public function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table)." $alter_type ";
+		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
-		if ($alter_type == 'DROP')
+		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->_protect_identifiers($fields);
+			return $sql.$this->db->protect_identifiers($fields);
 		}
 
-		$sql .= $this->_process_fields($fields);
-
-		if ($after_field != '')
-		{
-			$sql .= ' AFTER ' . $this->db->_protect_identifiers($after_field);
-		}
-
-		return $sql;
+		return $sql.$this->_process_fields($fields)
+			.($after_field != '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
 	}
 
 	// --------------------------------------------------------------------
@@ -268,18 +225,16 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	 *
 	 * 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, $new_table_name)
+	public function _rename_table($table_name, $new_table_name)
 	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table_name)." RENAME TO ".$this->db->_protect_identifiers($new_table_name);
-		return $sql;
+		return 'ALTER TABLE '.$this->db->protect_identifiers($table_name).' RENAME TO '.$this->db->protect_identifiers($new_table_name);
 	}
 
 }
 
 /* End of file mysql_forge.php */
-/* Location: ./system/database/drivers/mysql/mysql_forge.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysql/mysql_forge.php */
diff --git a/system/database/drivers/mysql/mysql_result.php b/system/database/drivers/mysql/mysql_result.php
index dcb99cd60..8f04a936d 100644
--- a/system/database/drivers/mysql/mysql_result.php
+++ b/system/database/drivers/mysql/mysql_result.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// --------------------------------------------------------------------
-
 /**
  * MySQL Result Class
  *
@@ -41,10 +39,9 @@ class CI_DB_mysql_result extends CI_DB_result {
 	/**
 	 * Number of rows in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_rows()
+	public function num_rows()
 	{
 		return @mysql_num_rows($this->result_id);
 	}
@@ -54,10 +51,9 @@ class CI_DB_mysql_result extends CI_DB_result {
 	/**
 	 * Number of fields in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_fields()
+	public function num_fields()
 	{
 		return @mysql_num_fields($this->result_id);
 	}
@@ -69,10 +65,9 @@ class CI_DB_mysql_result extends CI_DB_result {
 	 *
 	 * Generates an array of column names
 	 *
-	 * @access	public
 	 * @return	array
 	 */
-	function list_fields()
+	public function list_fields()
 	{
 		$field_names = array();
 		while ($field = mysql_fetch_field($this->result_id))
@@ -90,25 +85,21 @@ class CI_DB_mysql_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()
 	{
 		$retval = array();
 		while ($field = mysql_fetch_object($this->result_id))
 		{
 			preg_match('/([a-zA-Z]+)(\(\d+\))?/', $field->Type, $matches);
 
-			$type = (array_key_exists(1, $matches)) ? $matches[1] : NULL;
-			$length = (array_key_exists(2, $matches)) ? preg_replace('/[^\d]/', '', $matches[2]) : NULL;
-
-			$F				= new stdClass();
-			$F->name		= $field->Field;
-			$F->type		= $type;
-			$F->default		= $field->Default;
-			$F->max_length	= $length;
-			$F->primary_key = ( $field->Key == 'PRI' ? 1 : 0 );
+			$F		= new stdClass();
+			$F->name	= $field->Field;
+			$F->type	= ( ! empty($matches[1])) ? $matches[1] : NULL;
+			$F->default	= $field->Default;
+			$F->max_length	= ( ! empty($matches[2])) ? preg_replace('/[^\d]/', '', $matches[2]) : NULL;
+			$F->primary_key = (int) ($field->Key === 'PRI');
 
 			$retval[] = $F;
 		}
@@ -121,9 +112,9 @@ class CI_DB_mysql_result extends CI_DB_result {
 	/**
 	 * Free the result
 	 *
-	 * @return	null
+	 * @return	void
 	 */
-	function free_result()
+	public function free_result()
 	{
 		if (is_resource($this->result_id))
 		{
@@ -137,14 +128,13 @@ class CI_DB_mysql_result extends CI_DB_result {
 	/**
 	 * Data Seek
 	 *
-	 * Moves the internal pointer to the desired offset.  We call
+	 * 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($n = 0)
+	protected function _data_seek($n = 0)
 	{
 		return mysql_data_seek($this->result_id, $n);
 	}
@@ -156,10 +146,9 @@ class CI_DB_mysql_result extends CI_DB_result {
 	 *
 	 * Returns the result set as an array
 	 *
-	 * @access	private
 	 * @return	array
 	 */
-	function _fetch_assoc()
+	protected function _fetch_assoc()
 	{
 		return mysql_fetch_assoc($this->result_id);
 	}
@@ -171,16 +160,14 @@ class CI_DB_mysql_result extends CI_DB_result {
 	 *
 	 * Returns the result set as an object
 	 *
-	 * @access	private
 	 * @return	object
 	 */
-	function _fetch_object()
+	protected function _fetch_object()
 	{
 		return mysql_fetch_object($this->result_id);
 	}
 
 }
 
-
 /* End of file mysql_result.php */
-/* Location: ./system/database/drivers/mysql/mysql_result.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysql/mysql_result.php */
diff --git a/system/database/drivers/mysql/mysql_utility.php b/system/database/drivers/mysql/mysql_utility.php
index 703524165..952f887fe 100644
--- a/system/database/drivers/mysql/mysql_utility.php
+++ b/system/database/drivers/mysql/mysql_utility.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQL Utility Class
  *
@@ -39,12 +37,11 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 	/**
 	 * List databases
 	 *
-	 * @access	private
-	 * @return	bool
+	 * @return	string
 	 */
-	function _list_databases()
+	public function _list_databases()
 	{
-		return "SHOW DATABASES";
+		return 'SHOW DATABASES';
 	}
 
 	// --------------------------------------------------------------------
@@ -54,13 +51,12 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 	 *
 	 * Generates a platform-specific query so that a table can be optimized
 	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _optimize_table($table)
+	public function _optimize_table($table)
 	{
-		return "OPTIMIZE TABLE ".$this->db->_escape_identifiers($table);
+		return 'OPTIMIZE TABLE '.$this->db->protect_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -70,26 +66,24 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 	 *
 	 * Generates a platform-specific query so that a table can be repaired
 	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _repair_table($table)
+	public function _repair_table($table)
 	{
-		return "REPAIR TABLE ".$this->db->_escape_identifiers($table);
+		return 'REPAIR TABLE '.$this->db->protect_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
 	/**
 	 * MySQL Export
 	 *
-	 * @access	private
 	 * @param	array	Preferences
 	 * @return	mixed
 	 */
-	function _backup($params = array())
+	public function _backup($params = array())
 	{
-		if (count($params) == 0)
+		if (count($params) === 0)
 		{
 			return FALSE;
 		}
@@ -99,16 +93,16 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 
 		// Build the output
 		$output = '';
-		foreach ((array)$tables as $table)
+		foreach ( (array) $tables as $table)
 		{
 			// Is the table in the "ignore" list?
-			if (in_array($table, (array)$ignore, TRUE))
+			if (in_array($table, (array) $ignore, TRUE))
 			{
 				continue;
 			}
 
 			// Get the table schema
-			$query = $this->db->query("SHOW CREATE TABLE `".$this->db->database.'`.`'.$table.'`');
+			$query = $this->db->query('SHOW CREATE TABLE '.$this->db->protect_identifiers($this->db->database).'.'.$this->db->protect_identifiers($table));
 
 			// No result means the table name was invalid
 			if ($query === FALSE)
@@ -121,7 +115,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 
 			if ($add_drop == TRUE)
 			{
-				$output .= 'DROP TABLE IF EXISTS '.$table.';'.$newline.$newline;
+				$output .= 'DROP TABLE IF EXISTS '.$this->db->protect_identifiers($table).';'.$newline.$newline;
 			}
 
 			$i = 0;
@@ -141,7 +135,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 			}
 
 			// Grab all the data from the current table
-			$query = $this->db->query("SELECT * FROM $table");
+			$query = $this->db->query('SELECT * FROM '.$this->db->protect_identifiers($table));
 
 			if ($query->num_rows() == 0)
 			{
@@ -149,7 +143,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 			}
 
 			// Fetch the field names and determine if the field is an
-			// integer type.  We use this info to decide whether to
+			// integer type. We use this info to decide whether to
 			// surround the data with quotes or not
 
 			$i = 0;
@@ -158,20 +152,17 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 			while ($field = mysql_fetch_field($query->result_id))
 			{
 				// Most versions of MySQL store timestamp as a string
-				$is_int[$i] = (in_array(
-										strtolower(mysql_field_type($query->result_id, $i)),
-										array('tinyint', 'smallint', 'mediumint', 'int', 'bigint'), //, 'timestamp'),
-										TRUE)
-										) ? TRUE : FALSE;
+				$is_int[$i] = in_array(strtolower(mysql_field_type($query->result_id, $i)),
+							array('tinyint', 'smallint', 'mediumint', 'int', 'bigint'), //, 'timestamp'),
+							TRUE);
 
 				// Create a string of field names
-				$field_str .= '`'.$field->name.'`, ';
+				$field_str .= $this->db->protect_identifiers($field->name).', ';
 				$i++;
 			}
 
 			// Trim off the end comma
-			$field_str = preg_replace( "/, $/" , "" , $field_str);
-
+			$field_str = preg_replace('/, $/' , '', $field_str);
 
 			// Build the insert string
 			foreach ($query->result_array() as $row)
@@ -189,14 +180,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 					else
 					{
 						// Escape the data if it's not an integer
-						if ($is_int[$i] == FALSE)
-						{
-							$val_str .= $this->db->escape($v);
-						}
-						else
-						{
-							$val_str .= $v;
-						}
+						$val_str .= ($is_int[$i] == FALSE) ? $this->db->escape($v) : $v;
 					}
 
 					// Append a comma
@@ -205,10 +189,10 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 				}
 
 				// Remove the comma at the end of the string
-				$val_str = preg_replace( "/, $/" , "" , $val_str);
+				$val_str = preg_replace('/, $/' , '', $val_str);
 
 				// Build the INSERT string
-				$output .= 'INSERT INTO '.$table.' ('.$field_str.') VALUES ('.$val_str.');'.$newline;
+				$output .= 'INSERT INTO '.$this->db->protect_identifiers($table).' ('.$field_str.') VALUES ('.$val_str.');'.$newline;
 			}
 
 			$output .= $newline.$newline;
@@ -216,7 +200,8 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 
 		return $output;
 	}
+
 }
 
 /* End of file mysql_utility.php */
-/* Location: ./system/database/drivers/mysql/mysql_utility.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysql/mysql_utility.php */
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index aff62a37d..dbba12e15 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,10 +25,8 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
- * MySQLi Database Adapter Class - MySQLi only works with PHP 5
+ * MySQLi Database Adapter Class
  *
  * Note: _DB is an extender class that the app controller
  * creates dynamically based on whether the active record
@@ -42,52 +40,40 @@
  */
 class CI_DB_mysqli_driver extends CI_DB {
 
-	var $dbdriver = 'mysqli';
+	public $dbdriver = 'mysqli';
 
 	// The character used for escaping
-	var $_escape_char = '`';
+	protected $_escape_char = '`';
 
 	// clause and character used for LIKE escape sequences - not used in MySQL
-	var $_like_escape_str = '';
-	var $_like_escape_chr = '';
+	protected $_like_escape_str = '';
+	protected $_like_escape_chr = '';
 
 	/**
 	 * The syntax to count rows is slightly different across different
 	 * database engines, so this string appears in each driver and is
 	 * used for the count_all() and count_all_results() functions.
 	 */
-	var $_count_string = "SELECT COUNT(*) AS ";
-	var $_random_keyword = ' RAND()'; // database specific random keyword
+	protected $_count_string = 'SELECT COUNT(*) AS ';
+	protected $_random_keyword = ' RAND()'; // database specific random keyword
 
 	/**
 	 * Whether to use the MySQL "delete hack" which allows the number
 	 * of affected rows to be shown. Uses a preg_replace when enabled,
 	 * adding a bit more processing to all queries.
 	 */
-	var $delete_hack = TRUE;
-
-	// whether SET NAMES must be used to set the character set
-	var $use_set_names;
-
-	// --------------------------------------------------------------------
+	public $delete_hack = TRUE;
 
 	/**
 	 * Non-persistent database connection
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @return	object
 	 */
-	function db_connect()
+	public function db_connect()
 	{
-		if ($this->port != '')
-		{
-			return @mysqli_connect($this->hostname, $this->username, $this->password, $this->database, $this->port);
-		}
-		else
-		{
-			return @mysqli_connect($this->hostname, $this->username, $this->password, $this->database);
-		}
-
+		return ($this->port != '')
+			? @mysqli_connect($this->hostname, $this->username, $this->password, $this->database, $this->port)
+			: @mysqli_connect($this->hostname, $this->username, $this->password, $this->database);
 	}
 
 	// --------------------------------------------------------------------
@@ -95,12 +81,19 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Persistent database connection
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @return	object
 	 */
-	function db_pconnect()
+	public function db_pconnect()
 	{
-		return $this->db_connect();
+		// Persistent connection support was added in PHP 5.3.0
+		if ( ! is_php('5.3'))
+		{
+			return $this->db_connect();
+		}
+
+		return ($this->port != '')
+			? @mysqli_connect('p:'.$this->hostname, $this->username, $this->password, $this->database, $this->port)
+			: @mysqli_connect('p:'.$this->hostname, $this->username, $this->password, $this->database);
 	}
 
 	// --------------------------------------------------------------------
@@ -111,10 +104,9 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * Keep / reestablish the db connection if no queries have been
 	 * sent for a length of time exceeding the server's idle timeout
 	 *
-	 * @access	public
 	 * @return	void
 	 */
-	function reconnect()
+	public function reconnect()
 	{
 		if (mysqli_ping($this->conn_id) === FALSE)
 		{
@@ -127,12 +119,23 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Select the database
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @param	string	database name
+	 * @return	bool
 	 */
-	function db_select()
+	public function db_select($database = '')
 	{
-		return @mysqli_select_db($this->conn_id, $this->database);
+		if ($database === '')
+		{
+			$database = $this->database;
+		}
+
+		if (@mysqli_select_db($this->conn_id, $database))
+		{
+			$this->database = $database;
+			return TRUE;
+		}
+
+		return FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -140,12 +143,11 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Set client character set
 	 *
-	 * @access	private
 	 * @param	string
 	 * @param	string
-	 * @return	resource
+	 * @return	bool
 	 */
-	function _db_set_charset($charset, $collation)
+	protected function _db_set_charset($charset, $collation)
 	{
 		return function_exists('mysqli_set_charset')
 			? @mysqli_set_charset($this->conn_id, $charset)
@@ -157,12 +159,11 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Version number query string
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function _version()
+	protected function _version()
 	{
-		return "SELECT version() AS ver";
+		return @mysqli_get_server_info($this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -170,15 +171,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Execute the query
 	 *
-	 * @access	private called by the base class
 	 * @param	string	an SQL query
-	 * @return	resource
+	 * @return	mixed
 	 */
-	function _execute($sql)
+	protected function _execute($sql)
 	{
-		$sql = $this->_prep_query($sql);
-		$result = @mysqli_query($this->conn_id, $sql);
-		return $result;
+		return @mysqli_query($this->conn_id, $this->_prep_query($sql));
 	}
 
 	// --------------------------------------------------------------------
@@ -188,20 +186,16 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * 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($sql)
+	protected function _prep_query($sql)
 	{
-		// "DELETE FROM TABLE" returns 0 affected rows This hack modifies
-		// the query so that it returns the number of affected rows
-		if ($this->delete_hack === TRUE)
+		// mysqli_affected_rows() returns 0 for "DELETE FROM TABLE" queries. This hack
+		// modifies the query so that it a proper number of affected rows is returned.
+		if ($this->delete_hack === TRUE && preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $sql))
 		{
-			if (preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $sql))
-			{
-				$sql = preg_replace("/^\s*DELETE\s+FROM\s+(\S+)\s*$/", "DELETE FROM \\1 WHERE 1=1", $sql);
-			}
+			return preg_replace('/^\s*DELETE\s+FROM\s+(\S+)\s*$/', 'DELETE FROM \\1 WHERE 1=1', $sql);
 		}
 
 		return $sql;
@@ -212,18 +206,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Begin Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_begin($test_mode = FALSE)
+	public function trans_begin($test_mode = FALSE)
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -231,7 +219,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 		// Reset the transaction failure flag.
 		// If the $test_mode flag is set to TRUE transactions will be rolled back
 		// even if the queries produce a successful result.
-		$this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;
+		$this->_trans_failure = ($test_mode === TRUE);
 
 		$this->simple_query('SET AUTOCOMMIT=0');
 		$this->simple_query('START TRANSACTION'); // can also be BEGIN or BEGIN WORK
@@ -243,18 +231,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Commit Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_commit()
+	public function trans_commit()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -269,18 +251,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Rollback Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_rollback()
+	public function trans_rollback()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -295,12 +271,11 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Escape String
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	bool	whether or not the string will be used in a LIKE condition
 	 * @return	string
 	 */
-	function escape_str($str, $like = FALSE)
+	public function escape_str($str, $like = FALSE)
 	{
 		if (is_array($str))
 		{
@@ -312,7 +287,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 			return $str;
 		}
 
-		if (function_exists('mysqli_real_escape_string') AND is_object($this->conn_id))
+		if (function_exists('mysqli_real_escape_string') && is_object($this->conn_id))
 		{
 			$str = mysqli_real_escape_string($this->conn_id, $str);
 		}
@@ -328,7 +303,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 		// escape LIKE condition wildcards
 		if ($like === TRUE)
 		{
-			$str = str_replace(array('%', '_'), array('\\%', '\\_'), $str);
+			return str_replace(array('%', '_'), array('\\%', '\\_'), $str);
 		}
 
 		return $str;
@@ -339,10 +314,9 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Affected Rows
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function affected_rows()
+	public function affected_rows()
 	{
 		return @mysqli_affected_rows($this->conn_id);
 	}
@@ -352,10 +326,9 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Insert ID
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function insert_id()
+	public function insert_id()
 	{
 		return @mysqli_insert_id($this->conn_id);
 	}
@@ -368,27 +341,25 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * Generates a platform-specific query string that counts all records in
 	 * the specified database
 	 *
-	 * @access	public
 	 * @param	string
 	 * @return	string
 	 */
-	function count_all($table = '')
+	public function count_all($table = '')
 	{
 		if ($table == '')
 		{
 			return 0;
 		}
 
-		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
-
+		$query = $this->query($this->_count_string.$this->_protect_identifiers('numrows').' FROM '.$this->_protect_identifiers($table, TRUE, NULL, FALSE));
 		if ($query->num_rows() == 0)
 		{
 			return 0;
 		}
 
-		$row = $query->row();
+		$query = $query->row();
 		$this->_reset_select();
-		return (int) $row->numrows;
+		return (int) $query->numrows;
 	}
 
 	// --------------------------------------------------------------------
@@ -399,16 +370,16 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * Generates a platform-specific query string so that the table names can be fetched
 	 *
 	 * @access	private
-	 * @param	boolean
+	 * @param	bool
 	 * @return	string
 	 */
-	function _list_tables($prefix_limit = FALSE)
+	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SHOW TABLES FROM ".$this->_escape_char.$this->database.$this->_escape_char;
+		$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
 
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		if ($prefix_limit !== FALSE && $this->dbprefix != '')
 		{
-			$sql .= " LIKE '".$this->escape_like_str($this->dbprefix)."%'";
+			return $sql." LIKE '".$this->escape_like_str($this->dbprefix)."%'";
 		}
 
 		return $sql;
@@ -421,13 +392,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the column names can be fetched
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _list_columns($table = '')
+	protected function _list_columns($table = '')
 	{
-		return "SHOW COLUMNS FROM ".$this->_protect_identifiers($table, TRUE, NULL, FALSE);
+		return 'SHOW COLUMNS FROM '.$this->_protect_identifiers($table, TRUE, NULL, FALSE);
 	}
 
 	// --------------------------------------------------------------------
@@ -437,13 +407,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query so that the column data can be retrieved
 	 *
-	 * @access	public
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _field_data($table)
+	protected function _field_data($table)
 	{
-		return "DESCRIBE ".$table;
+		return 'DESCRIBE '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -451,10 +420,9 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * The error message string
 	 *
-	 * @access	private
 	 * @return	string
 	 */
-	function _error_message()
+	protected function _error_message()
 	{
 		return mysqli_error($this->conn_id);
 	}
@@ -464,10 +432,9 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * The error message number
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	int
 	 */
-	function _error_number()
+	protected function _error_number()
 	{
 		return mysqli_errno($this->conn_id);
 	}
@@ -479,11 +446,10 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * This function escapes column and table names
 	 *
-	 * @access	private
 	 * @param	string
 	 * @return	string
 	 */
-	function _escape_identifiers($item)
+	public function _escape_identifiers($item)
 	{
 		if ($this->_escape_char == '')
 		{
@@ -494,24 +460,20 @@ class CI_DB_mysqli_driver extends CI_DB {
 		{
 			if (strpos($item, '.'.$id) !== FALSE)
 			{
-				$str = $this->_escape_char. str_replace('.', $this->_escape_char.'.', $item);
+				$item = str_replace('.', $this->_escape_char.'.', $item);
 
 				// remove duplicates if the user already included the escape
-				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item);
 			}
 		}
 
 		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;
+			$item = str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item);
 		}
 
 		// remove duplicates if the user already included the escape
-		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item.$this->_escape_char);
 	}
 
 	// --------------------------------------------------------------------
@@ -522,11 +484,10 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * This function implicitly groups FROM tables so there is no confusion
 	 * about operator precedence in harmony with SQL standards
 	 *
-	 * @access	public
-	 * @param	type
-	 * @return	type
+	 * @param	string
+	 * @return	string
 	 */
-	function _from_tables($tables)
+	protected function _from_tables($tables)
 	{
 		if ( ! is_array($tables))
 		{
@@ -543,15 +504,14 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific insert string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the insert keys
 	 * @param	array	the insert values
 	 * @return	string
 	 */
-	function _insert($table, $keys, $values)
+	protected function _insert($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+		return 'INSERT INTO '.$table.' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -561,15 +521,14 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * 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_batch($table, $keys, $values)
+	protected function _insert_batch($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES ".implode(', ', $values);
+		return 'INSERT INTO '.$table.' ('.implode(', ', $keys).') VALUES '.implode(', ', $values);
 	}
 
 	// --------------------------------------------------------------------
@@ -580,17 +539,16 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific replace 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 _replace($table, $keys, $values)
+	protected function _replace($table, $keys, $values)
 	{
-		return "REPLACE INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+		return 'REPLACE INTO '.$table.' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
-	
+
 	// --------------------------------------------------------------------
 
 	/**
@@ -598,7 +556,6 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the update data
 	 * @param	array	the where clause
@@ -606,24 +563,17 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * @param	array	the limit clause
 	 * @return	string
 	 */
-	function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
+	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
 	{
 		foreach ($values as $key => $val)
 		{
-			$valstr[] = $key." = ".$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 $sql;
+		return 'UPDATE '.$table.' SET '.implode(', ', $valstr)
+			.(($where != '' && count($where) > 0) ? ' WHERE '.implode(' ', $where) : '')
+			.(count($orderby) > 0 ? ' ORDER BY '.implode(', ', $orderby) : '')
+			.( ! $limit ? '' : ' LIMIT '.$limit);
 	}
 
 	// --------------------------------------------------------------------
@@ -633,17 +583,14 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the update data
 	 * @param	array	the where clause
 	 * @return	string
 	 */
-	function _update_batch($table, $values, $index, $where = NULL)
+	protected function _update_batch($table, $values, $index, $where = NULL)
 	{
 		$ids = array();
-		$where = ($where != '' AND count($where) >=1) ? implode(" ", $where).' AND ' : '';
-
 		foreach ($values as $key => $val)
 		{
 			$ids[] = $val[$index];
@@ -657,25 +604,19 @@ class CI_DB_mysqli_driver extends CI_DB {
 			}
 		}
 
-		$sql = "UPDATE ".$table." SET ";
 		$cases = '';
-
 		foreach ($final as $k => $v)
 		{
-			$cases .= $k.' = CASE '."\n";
-			foreach ($v as $row)
-			{
-				$cases .= $row."\n";
-			}
-
-			$cases .= 'ELSE '.$k.' END, ';
+			$cases .= $k.' = CASE '."\n"
+				.implode("\n", $v)."\n"
+				.'ELSE '.$k.' END, ';
 		}
 
-		$sql .= substr($cases, 0, -2);
+		$where = ($where != '' && count($where) > 0) ? implode(' ', $where).' AND ' : '';
 
-		$sql .= ' WHERE '.$where.$index.' IN ('.implode(',', $ids).')';
-
-		return $sql;
+		return 'UPDATE '.$table.' SET '.substr($cases, 0, -2)
+			.' WHERE '.(($where != '' && count($where) > 0) ? implode(' ', $where).' AND ' : '')
+			.$index.' IN('.implode(',', $ids).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -687,13 +628,12 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 * 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($table)
+	protected function _truncate($table)
 	{
-		return "TRUNCATE ".$table;
+		return 'TRUNCATE '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -703,31 +643,26 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * 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(), $limit = FALSE)
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
 	{
 		$conditions = '';
-
 		if (count($where) > 0 OR count($like) > 0)
 		{
-			$conditions = "\nWHERE ";
-			$conditions .= implode("\n", $this->ar_where);
+			$conditions = "\nWHERE ".implode("\n", $this->ar_where);
 
 			if (count($where) > 0 && count($like) > 0)
 			{
-				$conditions .= " AND ";
+				$conditions .= ' AND ';
 			}
 			$conditions .= implode("\n", $like);
 		}
 
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
-
-		return "DELETE FROM ".$table.$conditions.$limit;
+		return 'DELETE FROM '.$table.$conditions.( ! $limit ? '' : ' LIMIT '.$limit);
 	}
 
 	// --------------------------------------------------------------------
@@ -737,22 +672,15 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific LIMIT clause
 	 *
-	 * @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	int	the number of rows to limit the query to
+	 * @param	int	the offset value
 	 * @return	string
 	 */
-	function _limit($sql, $limit, $offset)
+	protected function _limit($sql, $limit, $offset)
 	{
-		$sql .= "LIMIT ".$limit;
-
-		if ($offset > 0)
-		{
-			$sql .= " OFFSET ".$offset;
-		}
-
-		return $sql;
+		return $sql.' LIMIT '.$limit
+			.($offset > 0 ? ' OFFSET '.$offset : '');
 	}
 
 	// --------------------------------------------------------------------
@@ -760,18 +688,15 @@ class CI_DB_mysqli_driver extends CI_DB {
 	/**
 	 * Close DB Connection
 	 *
-	 * @access	public
-	 * @param	resource
+	 * @param	object
 	 * @return	void
 	 */
-	function _close($conn_id)
+	protected function _close($conn_id)
 	{
 		@mysqli_close($conn_id);
 	}
 
-
 }
 
-
 /* End of file mysqli_driver.php */
-/* Location: ./system/database/drivers/mysqli/mysqli_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysqli/mysqli_driver.php */
diff --git a/system/database/drivers/mysqli/mysqli_forge.php b/system/database/drivers/mysqli/mysqli_forge.php
index 590efa939..7de036127 100644
--- a/system/database/drivers/mysqli/mysqli_forge.php
+++ b/system/database/drivers/mysqli/mysqli_forge.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQLi Forge Class
  *
@@ -39,13 +37,12 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	/**
 	 * Create database
 	 *
-	 * @access	private
 	 * @param	string	the database name
-	 * @return	bool
+	 * @return	string
 	 */
-	function _create_database($name)
+	public function _create_database($name)
 	{
-		return "CREATE DATABASE ".$name;
+		return 'CREATE DATABASE '.$name;
 	}
 
 	// --------------------------------------------------------------------
@@ -53,13 +50,12 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	/**
 	 * Drop database
 	 *
-	 * @access	private
 	 * @param	string	the database name
-	 * @return	bool
+	 * @return	string
 	 */
-	function _drop_database($name)
+	public function _drop_database($name)
 	{
-		return "DROP DATABASE ".$name;
+		return 'DROP DATABASE '.$name;
 	}
 
 	// --------------------------------------------------------------------
@@ -67,68 +63,35 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	/**
 	 * Process Fields
 	 *
-	 * @access	private
 	 * @param	mixed	the fields
 	 * @return	string
 	 */
-	function _process_fields($fields)
+	public function _process_fields($fields)
 	{
 		$current_field_count = 0;
 		$sql = '';
 
-		foreach ($fields as $field=>$attributes)
+		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";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->_protect_identifiers($field);
-
-				if (array_key_exists('NAME', $attributes))
-				{
-					$sql .= ' '.$this->db->_protect_identifiers($attributes['NAME']).' ';
-				}
-
-				if (array_key_exists('TYPE', $attributes))
-				{
-					$sql .=  ' '.$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';
-				}
+				$sql .= "\n\t".$this->db->protect_identifiers($field)
+					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '')
+					.( ! empty($attributes['TYPE']) ? ' '.$attributes['TYPE'] : '')
+					.( ! empty($attributes['CONSTRAINT']) ? '('.$attributes['CONSTRAINT'].')' : '')
+					.(( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
+					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
+					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
+					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
 			}
 
 			// don't add a comma on the end of the last field
@@ -146,15 +109,14 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	/**
 	 * Create Table
 	 *
-	 * @access	private
 	 * @param	string	the table name
 	 * @param	mixed	the fields
 	 * @param	mixed	primary key(s)
 	 * @param	mixed	key(s)
-	 * @param	boolean	should 'IF NOT EXISTS' be added to the SQL
+	 * @param	bool	should 'IF NOT EXISTS' be added to the SQL
 	 * @return	bool
 	 */
-	function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
+	public function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
 	{
 		$sql = 'CREATE TABLE ';
 
@@ -163,15 +125,12 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= $this->db->_escape_identifiers($table)." (";
-
-		$sql .= $this->_process_fields($fields);
+		$sql .= $this->db->_escape_identifiers($table).' ('.$this->_process_fields($fields);
 
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->_protect_identifiers(implode('_', $primary_keys));
-			$primary_keys = $this->db->_protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY ".$key_name." (" . implode(', ', $primary_keys) . ")";
+			$key_name = $this->db->protect_identifiers(implode('_', $primary_keys));
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -180,22 +139,20 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 			{
 				if (is_array($key))
 				{
-					$key_name = $this->db->_protect_identifiers(implode('_', $key));
-					$key = $this->db->_protect_identifiers($key);
+					$key_name = $this->db->protect_identifiers(implode('_', $key));
+					$key = $this->db->protect_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->_protect_identifiers($key);
+					$key_name = $this->db->protect_identifiers($key);
 					$key = array($key_name);
 				}
 
-				$sql .= ",\n\tKEY {$key_name} (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tKEY ".$key_name.' ('.implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n) DEFAULT CHARACTER SET {$this->db->char_set} COLLATE {$this->db->dbcollat};";
-
-		return $sql;
+		return $sql."\n) DEFAULT CHARACTER SET ".$this->db->char_set.' COLLATE '.$this->db->dbcollat.';';
 	}
 
 	// --------------------------------------------------------------------
@@ -203,12 +160,11 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	/**
 	 * Drop Table
 	 *
-	 * @access	private
 	 * @return	string
 	 */
-	function _drop_table($table)
+	public function _drop_table($table)
 	{
-		return "DROP TABLE IF EXISTS ".$this->db->_escape_identifiers($table);
+		return 'DROP TABLE IF EXISTS '.$this->db->_escape_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -219,31 +175,24 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	 * 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	array	fields
 	 * @param	string	the field after which we should add the new field
-	 * @return	object
+	 * @return	string
 	 */
-	function _alter_table($alter_type, $table, $fields, $after_field = '')
+	public function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table)." $alter_type ";
+		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
-		if ($alter_type == 'DROP')
-		{
-			return $sql.$this->db->_protect_identifiers($fields);
-		}
-
-		$sql .= $this->_process_fields($fields);
-
-		if ($after_field != '')
+		if ($alter_type === 'DROP')
 		{
-			$sql .= ' AFTER ' . $this->db->_protect_identifiers($after_field);
+			return $sql.$this->db->protect_identifiers($fields);
 		}
 
-		return $sql;
+		return $sql.$this->_process_fields($fields)
+			.($after_field != '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
 	}
 
 	// --------------------------------------------------------------------
@@ -253,18 +202,16 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	 *
 	 * 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, $new_table_name)
+	public function _rename_table($table_name, $new_table_name)
 	{
-		$sql = 'ALTER TABLE '.$this->db->_protect_identifiers($table_name)." RENAME TO ".$this->db->_protect_identifiers($new_table_name);
-		return $sql;
+		return 'ALTER TABLE '.$this->db->protect_identifiers($table_name).' RENAME TO '.$this->db->protect_identifiers($new_table_name);
 	}
 
 }
 
 /* End of file mysqli_forge.php */
-/* Location: ./system/database/drivers/mysqli/mysqli_forge.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysqli/mysqli_forge.php */
diff --git a/system/database/drivers/mysqli/mysqli_result.php b/system/database/drivers/mysqli/mysqli_result.php
index 89dd4ded8..0a50cccac 100644
--- a/system/database/drivers/mysqli/mysqli_result.php
+++ b/system/database/drivers/mysqli/mysqli_result.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQLi Result Class
  *
@@ -41,10 +39,9 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	/**
 	 * Number of rows in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_rows()
+	public function num_rows()
 	{
 		return @mysqli_num_rows($this->result_id);
 	}
@@ -54,10 +51,9 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	/**
 	 * Number of fields in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_fields()
+	public function num_fields()
 	{
 		return @mysqli_num_fields($this->result_id);
 	}
@@ -69,10 +65,9 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 *
 	 * Generates an array of column names
 	 *
-	 * @access	public
 	 * @return	array
 	 */
-	function list_fields()
+	public function list_fields()
 	{
 		$field_names = array();
 		while ($field = mysqli_fetch_field($this->result_id))
@@ -90,40 +85,36 @@ class CI_DB_mysqli_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()
 	{
 		$retval = array();
 		while ($field = mysqli_fetch_object($this->result_id))
 		{
 			preg_match('/([a-zA-Z]+)(\(\d+\))?/', $field->Type, $matches);
 
-			$type = (array_key_exists(1, $matches)) ? $matches[1] : NULL;
-			$length = (array_key_exists(2, $matches)) ? preg_replace('/[^\d]/', '', $matches[2]) : NULL;
-
-			$F				= new stdClass();
-			$F->name		= $field->Field;
-			$F->type		= $type;
-			$F->default		= $field->Default;
-			$F->max_length	= $length;
-			$F->primary_key = ( $field->Key == 'PRI' ? 1 : 0 );
+			$F		= new stdClass();
+			$F->name	= $field->Field;
+			$F->type	= ( ! empty($matches[1])) ? $matches[1] : NULL;
+			$F->default	= $field->Default;
+			$F->max_length	= ( ! empty($matches[2])) ? preg_replace('/[^\d]/', '', $matches[2]) : NULL;
+			$F->primary_key = (int) ($field->Key === 'PRI');
 
 			$retval[] = $F;
 		}
 
 		return $retval;
 	}
-	
+
 	// --------------------------------------------------------------------
 
 	/**
 	 * Free the result
 	 *
-	 * @return	null
+	 * @return	void
 	 */
-	function free_result()
+	public function free_result()
 	{
 		if (is_object($this->result_id))
 		{
@@ -141,10 +132,9 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 * this internally before fetching results to make sure the
 	 * result set starts at zero
 	 *
-	 * @access	private
 	 * @return	array
 	 */
-	function _data_seek($n = 0)
+	protected function _data_seek($n = 0)
 	{
 		return mysqli_data_seek($this->result_id, $n);
 	}
@@ -156,10 +146,9 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 *
 	 * Returns the result set as an array
 	 *
-	 * @access	private
 	 * @return	array
 	 */
-	function _fetch_assoc()
+	protected function _fetch_assoc()
 	{
 		return mysqli_fetch_assoc($this->result_id);
 	}
@@ -171,16 +160,14 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 *
 	 * Returns the result set as an object
 	 *
-	 * @access	private
 	 * @return	object
 	 */
-	function _fetch_object()
+	protected function _fetch_object()
 	{
 		return mysqli_fetch_object($this->result_id);
 	}
 
 }
 
-
 /* End of file mysqli_result.php */
-/* Location: ./system/database/drivers/mysqli/mysqli_result.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysqli/mysqli_result.php */
diff --git a/system/database/drivers/mysqli/mysqli_utility.php b/system/database/drivers/mysqli/mysqli_utility.php
index 76bd49e31..3fdc5c723 100644
--- a/system/database/drivers/mysqli/mysqli_utility.php
+++ b/system/database/drivers/mysqli/mysqli_utility.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * MySQLi Utility Class
  *
@@ -39,12 +37,11 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 	/**
 	 * List databases
 	 *
-	 * @access	private
-	 * @return	bool
+	 * @return	string
 	 */
-	function _list_databases()
+	public function _list_databases()
 	{
-		return "SHOW DATABASES";
+		return 'SHOW DATABASES';
 	}
 
 	// --------------------------------------------------------------------
@@ -54,13 +51,12 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 	 *
 	 * Generates a platform-specific query so that a table can be optimized
 	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _optimize_table($table)
+	public function _optimize_table($table)
 	{
-		return "OPTIMIZE TABLE ".$this->db->_escape_identifiers($table);
+		return 'OPTIMIZE TABLE '.$this->db->_escape_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -70,13 +66,12 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 	 *
 	 * Generates a platform-specific query so that a table can be repaired
 	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _repair_table($table)
+	public function _repair_table($table)
 	{
-		return "REPAIR TABLE ".$this->db->_escape_identifiers($table);
+		return 'REPAIR TABLE '.$this->db->_escape_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -84,11 +79,10 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 	/**
 	 * MySQLi Export
 	 *
-	 * @access	private
 	 * @param	array	Preferences
 	 * @return	mixed
 	 */
-	function _backup($params = array())
+	public function _backup($params = array())
 	{
 		// Currently unsupported
 		return $this->db->display_error('db_unsuported_feature');
@@ -96,4 +90,4 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 }
 
 /* End of file mysqli_utility.php */
-/* Location: ./system/database/drivers/mysqli/mysqli_utility.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mysqli/mysqli_utility.php */
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index c6621901b..6da6dc724 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -139,22 +139,6 @@ class CI_DB_oci8_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Set client character set
-	 *
-	 * @access	public
-	 * @param	string
-	 * @param	string
-	 * @return	resource
-	 */
-	public function db_set_charset($charset, $collation)
-	{
-		// this is done upon connect
-		return TRUE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Version number query string
 	 *
 	 * @access  protected
@@ -398,10 +382,9 @@ class CI_DB_oci8_driver extends CI_DB {
 	/**
 	 * Escape String
 	 *
-	 * @access  public
-	 * @param   string
+	 * @param	string
 	 * @param	bool	whether or not the string will be used in a LIKE condition
-	 * @return  string
+	 * @return	string
 	 */
 	public function escape_str($str, $like = FALSE)
 	{
@@ -415,15 +398,14 @@ class CI_DB_oci8_driver extends CI_DB {
 			return $str;
 		}
 
-		$str = remove_invisible_characters($str);
-		$str = str_replace("'", "''", $str);
+		$str = str_replace("'", "''", remove_invisible_characters($str));
 
 		// 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),
-								$str);
+			return str_replace(array($this->_like_escape_chr, '%', '_'),
+						array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
+						$str);
 		}
 
 		return $str;
@@ -547,13 +529,11 @@ class CI_DB_oci8_driver extends CI_DB {
 	/**
 	 * The error message string
 	 *
-	 * @access  protected
-	 * @return  string
+	 * @return	string
 	 */
 	protected function _error_message()
 	{
-		// If the error was during connection, no conn_id should be passed
-		$error = is_resource($this->conn_id) ? oci_error($this->conn_id) : oci_error();
+		$error = $this->_oci8_error_data();
 		return $error['message'];
 	}
 
@@ -562,19 +542,43 @@ class CI_DB_oci8_driver extends CI_DB {
 	/**
 	 * The error message number
 	 *
-	 * @access  protected
-	 * @return  integer
+	 * @return	string
 	 */
 	protected function _error_number()
 	{
-		// Same as _error_message()
-		$error = is_resource($this->conn_id) ? oci_error($this->conn_id) : oci_error();
+		$error = $this->_oci8_error_data();
 		return $error['code'];
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
+	 * OCI8-specific method to get errors.
+	 * Used by _error_message() and _error_code().
+	 *
+	 * @return	array
+	 */
+	protected function _oci8_error_data()
+	{
+		if (is_resource($this->curs_id))
+		{
+			return oci_error($this->curs_id);
+		}
+		elseif (is_resource($this->stmt_id))
+		{
+			return oci_error($this->stmt_id);
+		}
+		elseif (is_resource($this->conn_id))
+		{
+			return oci_error($this->conn_id);
+		}
+
+		return oci_error();
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Escape the SQL Identifiers
 	 *
 	 * This function escapes column and table names
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index 6ba39f0cd..abb660324 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -124,22 +124,6 @@ class CI_DB_odbc_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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
@@ -646,4 +630,4 @@ class CI_DB_odbc_driver extends CI_DB {
 
 
 /* End of file odbc_driver.php */
-/* Location: ./system/database/drivers/odbc/odbc_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/odbc/odbc_driver.php */
diff --git a/system/database/drivers/odbc/odbc_result.php b/system/database/drivers/odbc/odbc_result.php
index ba660856e..572e110ca 100644
--- a/system/database/drivers/odbc/odbc_result.php
+++ b/system/database/drivers/odbc/odbc_result.php
@@ -38,15 +38,27 @@
  */
 class CI_DB_odbc_result extends CI_DB_result {
 
+	public $num_rows;
+
 	/**
 	 * Number of rows in the result set
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function num_rows()
+	public function num_rows()
 	{
-		return @odbc_num_rows($this->result_id);
+		if (is_int($this->num_rows))
+		{
+			return $this->num_rows;
+		}
+
+		// Work-around for ODBC subdrivers that don't support num_rows()
+		if (($this->num_rows = @odbc_num_rows($this->result_id)) === -1)
+		{
+			$this->num_rows = count($this->result_array());
+		}
+
+		return $this->num_rows;
 	}
 
 	// --------------------------------------------------------------------
@@ -54,10 +66,9 @@ class CI_DB_odbc_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 @odbc_num_fields($this->result_id);
 	}
@@ -69,15 +80,19 @@ class CI_DB_odbc_result extends CI_DB_result {
 	 *
 	 * Generates an array of column names
 	 *
-	 * @access	public
 	 * @return	array
 	 */
-	function list_fields()
+	public function list_fields()
 	{
 		$field_names = array();
-		for ($i = 0; $i < $this->num_fields(); $i++)
+		$num_fields = $this->num_fields();
+
+		if ($num_fields > 0)
 		{
-			$field_names[]	= odbc_field_name($this->result_id, $i);
+			for ($i = 1; $i <= $num_fields; $i++)
+			{
+				$field_names[] = odbc_field_name($this->result_id, $i);
+			}
 		}
 
 		return $field_names;
@@ -90,22 +105,19 @@ class CI_DB_odbc_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()
 	{
 		$retval = array();
-		for ($i = 0; $i < $this->num_fields(); $i++)
+		for ($i = 0, $odbc_index = 1, $c = $this->num_fields(); $i < $c; $i++, $odbc_index++)
 		{
-			$F				= new stdClass();
-			$F->name		= odbc_field_name($this->result_id, $i);
-			$F->type		= odbc_field_type($this->result_id, $i);
-			$F->max_length	= odbc_field_len($this->result_id, $i);
-			$F->primary_key = 0;
-			$F->default		= '';
-
-			$retval[] = $F;
+			$retval[$i]			= new stdClass();
+			$retval[$i]->name		= odbc_field_name($this->result_id, $odbc_index);
+			$retval[$i]->type		= odbc_field_type($this->result_id, $odbc_index);
+			$retval[$i]->max_length		= odbc_field_len($this->result_id, $odbc_index);
+			$retval[$i]->primary_key	= 0;
+			$retval[$i]->default		= '';
 		}
 
 		return $retval;
@@ -237,4 +249,4 @@ class CI_DB_odbc_result extends CI_DB_result {
 
 
 /* End of file odbc_result.php */
-/* Location: ./system/database/drivers/odbc/odbc_result.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/odbc/odbc_result.php */
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index 4f4f44ba7..90f0fd791 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -46,9 +46,10 @@ class CI_DB_pdo_driver extends CI_DB {
 
 	// the character used to excape - not necessary for PDO
 	var $_escape_char = '';
+
+	// clause and character used for LIKE escape sequences
 	var $_like_escape_str;
 	var $_like_escape_chr;
-	
 
 	/**
 	 * The syntax to count rows is slightly different across different
@@ -57,29 +58,36 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	var $_count_string = "SELECT COUNT(*) AS ";
 	var $_random_keyword;
-	
+
+	// need to track the pdo DSN, driver and options
+	var $dsn;
+	var $pdodriver;
 	var $options = array();
 
 	function __construct($params)
 	{
 		parent::__construct($params);
-		
+
+		if (preg_match('/([^;]+):/', $this->dsn, $match) && count($match) == 2)
+		{
+			// If there is a minimum valid dsn string pattern found, we're done
+			// This is for general PDO users, who tend to have a full DSN string.
+			$this->pdodriver = end($match);
+		}
+		else
+		{
+			// Try to build a complete DSN string from params
+			$this->_connect_string($params);
+		}
+
 		// clause and character used for LIKE escape sequences
-		if (strpos($this->hostname, 'mysql') !== FALSE)
+		// this one depends on the driver being used
+		if ($this->pdodriver == 'mysql')
 		{
 			$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}";
 		}
-		else if (strpos($this->hostname, 'odbc') !== FALSE)
+		elseif ($this->pdodriver == 'odbc')
 		{
 			$this->_like_escape_str = " {escape '%s'} ";
 			$this->_like_escape_chr = '!';
@@ -90,14 +98,94 @@ class CI_DB_pdo_driver extends CI_DB {
 			$this->_like_escape_chr = '!';
 		}
 		
-		if (strpos($this->hostname, 'sqlite') === FALSE)
+		$this->trans_enabled   = FALSE;
+		$this->_random_keyword = ' RND('.time().')'; // database specific random keyword
+	}
+
+	/**
+	 * Connection String
+	 *
+	 * @access	private
+	 * @param	array
+	 * @return	void
+	 */
+	function _connect_string($params)
+	{
+		if (strpos($this->hostname, ':'))
 		{
-			$this->hostname .= ";dbname=".$this->database;
+			// hostname generally would have this prototype
+			// $db['hostname'] = 'pdodriver:host(/Server(/DSN))=hostname(/DSN);';
+			// We need to get the prefix (pdodriver used by PDO).
+			$dsnarray = explode(':', $this->hostname);
+			$this->pdodriver = $dsnarray[0];
+
+			// End dsn with a semicolon for extra backward compability
+			// if database property was not empty.
+			if ( ! empty($this->database))
+			{
+				$this->dsn .= rtrim($this->hostname, ';').';';
+			}
 		}
-		
-		$this->trans_enabled = FALSE;
+		else
+		{
+			// Invalid DSN, display an error
+			if ( ! array_key_exists('pdodriver', $params))
+			{
+				show_error('Invalid DB Connection String for PDO');
+			}
 
-		$this->_random_keyword = ' RND('.time().')'; // database specific random keyword
+			// Assuming that the following DSN string format is used:
+			// $dsn = 'pdo://username:password@hostname:port/database?pdodriver=pgsql';
+			$this->dsn = $this->pdodriver.':';
+
+			// Add hostname to the DSN for databases that need it
+			if ( ! empty($this->hostname) 
+				&& strpos($this->hostname, ':') === FALSE
+				&& in_array($this->pdodriver, array('informix', 'mysql', 'pgsql', 'sybase', 'mssql', 'dblib', 'cubrid')))
+			{
+			    $this->dsn .= 'host='.$this->hostname.';';
+			}
+
+			// Add a port to the DSN for databases that can use it
+			if ( ! empty($this->port) && in_array($this->pdodriver, array('informix', 'mysql', 'pgsql', 'ibm', 'cubrid')))
+			{
+			    $this->dsn .= 'port='.$this->port.';';
+			}
+		}
+
+		// Add the database name to the DSN, if needed
+	    if (stripos($this->dsn, 'dbname') === FALSE 
+	       && in_array($this->pdodriver, array('4D', 'pgsql', 'mysql', 'firebird', 'sybase', 'mssql', 'dblib', 'cubrid')))
+	    {
+	        $this->dsn .= 'dbname='.$this->database.';';
+	    }
+	    elseif (stripos($this->dsn, 'database') === FALSE && in_array($this->pdodriver, array('ibm', 'sqlsrv')))
+	    {
+	    	if (stripos($this->dsn, 'dsn') === FALSE)
+	    	{
+		        $this->dsn .= 'database='.$this->database.';';
+	    	}
+	    }
+	    elseif ($this->pdodriver === 'sqlite' && $this->dsn === 'sqlite:')
+	    {
+	        if ($this->database !== ':memory')
+	        {
+	            if ( ! file_exists($this->database))
+	            {
+	                show_error('Invalid DB Connection string for PDO SQLite');
+	            }
+
+	            $this->dsn .= (strpos($this->database, DIRECTORY_SEPARATOR) !== 0) ? DIRECTORY_SEPARATOR : '';
+	        }
+
+	        $this->dsn .= $this->database;
+	    }
+
+	    // Add charset to the DSN, if needed
+	    if ( ! empty($this->char_set) && in_array($this->pdodriver, array('4D', 'mysql', 'sybase', 'mssql', 'dblib', 'oci')))
+	    {
+	        $this->dsn .= 'charset='.$this->char_set.';';
+	    }
 	}
 
 	/**
@@ -108,9 +196,9 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function db_connect()
 	{
-		$this->options['PDO::ATTR_ERRMODE'] = PDO::ERRMODE_SILENT;
-		
-		return new PDO($this->hostname, $this->username, $this->password, $this->options);
+		$this->options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_SILENT;
+
+		return $this->pdo_connect();
 	}
 
 	// --------------------------------------------------------------------
@@ -123,10 +211,44 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function db_pconnect()
 	{
-		$this->options['PDO::ATTR_ERRMODE'] = PDO::ERRMODE_SILENT;
-		$this->options['PDO::ATTR_PERSISTENT'] = TRUE;
+		$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);
+		return $this->pdo_connect();
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * PDO connection
+	 *
+	 * @access	private called by the PDO driver class
+	 * @return	resource
+	 */
+	function pdo_connect()
+	{
+		// Refer : http://php.net/manual/en/ref.pdo-mysql.connection.php
+		if ($this->pdodriver == 'mysql' && is_php('5.3.6'))
+		{
+			$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] = "SET NAMES $this->char_set COLLATE '$this->dbcollat'";
+		}
+
+		// Connecting...
+		try 
+		{
+			$db = new PDO($this->dsn, $this->username, $this->password, $this->options);
+		} 
+		catch (PDOException $e) 
+		{
+			if ($this->db_debug && empty($this->failover))
+			{
+				$this->display_error($e->getMessage(), '', TRUE);
+			}
+
+			return FALSE;
+		}
+
+		return $db;
 	}
 
 	// --------------------------------------------------------------------
@@ -146,6 +268,7 @@ class CI_DB_pdo_driver extends CI_DB {
 		{
 			return $this->db->display_error('db_unsuported_feature');
 		}
+
 		return FALSE;
 	}
 
@@ -166,30 +289,13 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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()
+	protected function _version()
 	{
-		return $this->conn_id->getAttribute(PDO::ATTR_CLIENT_VERSION);
+		return $this->conn_id->getAttribute(PDO::ATTR_SERVER_VERSION);
 	}
 
 	// --------------------------------------------------------------------
@@ -204,6 +310,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	function _execute($sql)
 	{
 		$sql = $this->_prep_query($sql);
+
 		$result_id = $this->conn_id->query($sql);
 		
 		if (is_object($result_id))
@@ -231,6 +338,17 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _prep_query($sql)
 	{
+		if ($this->pdodriver === 'pgsql')
+		{
+			// Change the backtick(s) for Postgre
+			$sql = str_replace('`', '"', $sql);
+		}
+		elseif ($this->pdodriver === 'sqlite')
+		{
+			// Change the backtick(s) for SQLite
+			$sql = str_replace('`', '', $sql);
+		}
+
 		return $sql;
 	}
 
@@ -285,6 +403,7 @@ class CI_DB_pdo_driver extends CI_DB {
 		}
 
 		$ret = $this->conn->commit();
+		
 		return $ret;
 	}
 
@@ -310,6 +429,7 @@ class CI_DB_pdo_driver extends CI_DB {
 		}
 
 		$ret = $this->conn_id->rollBack();
+
 		return $ret;
 	}
 
@@ -348,7 +468,9 @@ class CI_DB_pdo_driver extends CI_DB {
 		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),
+								array($this->_like_escape_chr.'%', 
+								      $this->_like_escape_chr.'_', 
+								      $this->_like_escape_chr.$this->_like_escape_chr),
 								$str);
 		}
 
@@ -372,31 +494,19 @@ class CI_DB_pdo_driver extends CI_DB {
 
 	/**
 	 * Insert ID
-	 * 
-	 * @access	public
-	 * @return	integer
+	 *
+	 * @return	int
 	 */
-	function insert_id($name=NULL)
+	public function insert_id($name = NULL)
 	{
-		//Convenience method for postgres insertid
-		if (strpos($this->hostname, 'pgsql') !== FALSE)
+		if ($this->pdodriver === 'pgsql' && $name === NULL && $this->_version() >= '8.1')
 		{
-			$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);
+			$query = $this->query('SELECT LASTVAL() AS ins_id');
+			$query = $query->row();
+			return $query->ins_id;
 		}
+
+		return $this->conn_id->lastInsertId($name);
 	}
 
 	// --------------------------------------------------------------------
@@ -418,7 +528,9 @@ class CI_DB_pdo_driver extends CI_DB {
 			return 0;
 		}
 
-		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
+		$sql   = $this->_count_string.$this->_protect_identifiers('numrows').' FROM ';
+		$sql  .= $this->_protect_identifiers($table, TRUE, NULL, FALSE);
+		$query = $this->query($sql);
 
 		if ($query->num_rows() == 0)
 		{
@@ -427,6 +539,7 @@ class CI_DB_pdo_driver extends CI_DB {
 
 		$row = $query->row();
 		$this->_reset_select();
+
 		return (int) $row->numrows;
 	}
 
@@ -443,12 +556,19 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SHOW TABLES FROM `".$this->database."`";
+		if ($this->pdodriver == 'pgsql')
+		{
+			// Analog function to show all tables in postgre
+			$sql = "SELECT * FROM information_schema.tables WHERE table_schema = 'public'";
+		}
+		else
+		{
+			$sql = "SHOW TABLES FROM `".$this->database."`";
+		}
 
 		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
 		{
-			//$sql .= " LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
-			return FALSE; // not currently supported
+			return FALSE; 
 		}
 
 		return $sql;
@@ -467,7 +587,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _list_columns($table = '')
 	{
-		return "SHOW COLUMNS FROM ".$table;
+		return 'SHOW COLUMNS FROM '.$this->_from_tables($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -483,7 +603,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _field_data($table)
 	{
-		return "SELECT TOP 1 FROM ".$table;
+		return 'SELECT TOP 1 FROM '.$this->_from_tables($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -497,6 +617,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	function _error_message()
 	{
 		$error_array = $this->conn_id->errorInfo();
+
 		return $error_array[2];
 	}
 
@@ -544,8 +665,8 @@ class CI_DB_pdo_driver extends CI_DB {
 
 		if (strpos($item, '.') !== FALSE)
 		{
-			$str = $this->_escape_char.str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item).$this->_escape_char;
-			
+			$str  = $this->_escape_char.str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item);
+			$str .= $this->_escape_char;
 		}
 		else
 		{
@@ -575,7 +696,7 @@ class CI_DB_pdo_driver extends CI_DB {
 			$tables = array($tables);
 		}
 
-		return (count($tables) == 1) ? $tables[0] : '('.implode(', ', $tables).')';
+		return (count($tables) == 1) ? '`'.$tables[0].'`' : '('.implode(', ', $tables).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -593,7 +714,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _insert($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+		return 'INSERT INTO '.$this->_from_tables($table).' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
 	
 	// --------------------------------------------------------------------
@@ -611,7 +732,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _insert_batch($table, $keys, $values)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES ".implode(', ', $values);
+		return 'INSERT INTO '.$this->_from_tables($table).' ('.implode(', ', $keys).') VALUES '.implode(', ', $values);
 	}
 
 	// --------------------------------------------------------------------
@@ -636,14 +757,11 @@ class CI_DB_pdo_driver extends CI_DB {
 			$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) : '';
+		$limit   = ( ! $limit) ? '' : ' LIMIT '.$limit;
+		$orderby = (count($orderby) >= 1) ? ' ORDER BY '.implode(', ', $orderby) : '';
 
+		$sql  = 'UPDATE '.$this->_from_tables($table).' SET '.implode(', ', $valstr);
+		$sql .= ($where != '' && count($where) >= 1) ? ' WHERE '.implode(' ', $where) : '';
 		$sql .= $orderby.$limit;
 
 		return $sql;
@@ -664,8 +782,8 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _update_batch($table, $values, $index, $where = NULL)
 	{
-		$ids = array();
-		$where = ($where != '' AND count($where) >=1) ? implode(" ", $where).' AND ' : '';
+		$ids   = array();
+		$where = ($where != '' && count($where) >=1) ? implode(" ", $where).' AND ' : '';
 
 		foreach ($values as $key => $val)
 		{
@@ -680,12 +798,13 @@ class CI_DB_pdo_driver extends CI_DB {
 			}
 		}
 
-		$sql = "UPDATE ".$table." SET ";
+		$sql   = 'UPDATE '.$this->_from_tables($table).' SET ';
 		$cases = '';
 
 		foreach ($final as $k => $v)
 		{
 			$cases .= $k.' = CASE '."\n";
+
 			foreach ($v as $row)
 			{
 				$cases .= $row."\n";
@@ -695,7 +814,6 @@ class CI_DB_pdo_driver extends CI_DB {
 		}
 
 		$sql .= substr($cases, 0, -2);
-
 		$sql .= ' WHERE '.$where.$index.' IN ('.implode(',', $ids).')';
 
 		return $sql;
@@ -739,19 +857,20 @@ class CI_DB_pdo_driver extends CI_DB {
 
 		if (count($where) > 0 OR count($like) > 0)
 		{
-			$conditions = "\nWHERE ";
+			$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.$limit;
+		return 'DELETE FROM '.$this->_from_tables($table).$conditions.$limit;
 	}
 
 	// --------------------------------------------------------------------
@@ -769,27 +888,16 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	function _limit($sql, $limit, $offset)
 	{
-		if (strpos($this->hostname, 'cubrid') !== FALSE || strpos($this->hostname, 'sqlite') !== FALSE)
+		if ($this->pdodriver == 'cubrid' OR $this->pdodriver == 'sqlite')
 		{
-			if ($offset == 0)
-			{
-				$offset = '';
-			}
-			else
-			{
-				$offset .= ", ";
-			}
+			$offset = ($offset == 0) ? '' : $offset.', ';
 
-			return $sql."LIMIT ".$offset.$limit;
+			return $sql.'LIMIT '.$offset.$limit;
 		}
 		else
 		{
-			$sql .= "LIMIT ".$limit;
-
-			if ($offset > 0)
-			{
-				$sql .= " OFFSET ".$offset;
-			}
+			$sql .= 'LIMIT '.$limit;
+			$sql .= ($offset > 0) ? ' OFFSET '.$offset : '';
 			
 			return $sql;
 		}
@@ -809,10 +917,7 @@ class CI_DB_pdo_driver extends CI_DB {
 		$this->conn_id = null;
 	}
 
-
 }
 
-
-
 /* End of file pdo_driver.php */
-/* Location: ./system/database/drivers/pdo/pdo_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/pdo/pdo_driver.php */
diff --git a/system/database/drivers/pdo/pdo_forge.php b/system/database/drivers/pdo/pdo_forge.php
index 076415928..478b2dbfb 100644
--- a/system/database/drivers/pdo/pdo_forge.php
+++ b/system/database/drivers/pdo/pdo_forge.php
@@ -96,7 +96,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= $this->db->_escape_identifiers($table)." (";
+		$sql .= '`'.$this->db->_escape_identifiers($table).'` (';
 		$current_field_count = 0;
 
 		foreach ($fields as $field=>$attributes)
@@ -111,6 +111,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
+				$numeric    = array('SERIAL', 'INTEGER');
 
 				$sql .= "\n\t".$this->db->_protect_identifiers($field);
 
@@ -118,7 +119,11 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 
 				if (array_key_exists('CONSTRAINT', $attributes))
 				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
+					// Exception for Postgre numeric which not too happy with constraint within those type
+					if ( ! ($this->db->pdodriver == 'pgsql' && in_array($attributes['TYPE'], $numeric)))
+					{
+						$sql .= '('.$attributes['CONSTRAINT'].')';
+					}
 				}
 
 				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
@@ -219,7 +224,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 	 */
 	function _alter_table($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);
+		$sql = 'ALTER TABLE `'.$this->db->_protect_identifiers($table)."` $alter_type ".$this->db->_protect_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type == 'DROP')
@@ -271,7 +276,6 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 		return $sql;
 	}
 
-
 }
 
 /* End of file pdo_forge.php */
diff --git a/system/database/drivers/pdo/pdo_result.php b/system/database/drivers/pdo/pdo_result.php
index 6b523b001..c333abc40 100644
--- a/system/database/drivers/pdo/pdo_result.php
+++ b/system/database/drivers/pdo/pdo_result.php
@@ -39,6 +39,16 @@
 class CI_DB_pdo_result extends CI_DB_result {
 
 	/**
+	 * @var bool  Hold the flag whether a result handler already fetched before
+	 */
+	protected $is_fetched = FALSE;
+
+	/**
+	 * @var mixed Hold the fetched assoc array of a result handler
+	 */
+	protected $result_assoc;
+
+	/**
 	 * Number of rows in the result set
 	 *
 	 * @access	public
@@ -46,7 +56,59 @@ class CI_DB_pdo_result extends CI_DB_result {
 	 */
 	function num_rows()
 	{
-		return $this->result_id->rowCount();
+		if (empty($this->result_id) OR ! is_object($this->result_id))
+		{
+			// invalid result handler
+			return 0;
+		}
+		elseif (($num_rows = $this->result_id->rowCount()) && $num_rows > 0)
+		{
+			// If rowCount return something, we're done.
+			return $num_rows;
+		}
+
+		// Fetch the result, instead perform another extra query
+		return ($this->is_fetched && is_array($this->result_assoc)) ? count($this->result_assoc) : count($this->result_assoc());
+	}
+
+	/**
+	 * Fetch the result handler
+	 *
+	 * @access	public
+	 * @return	mixed
+	 */
+	function result_assoc()
+	{
+		// If the result already fetched before, use that one
+		if (count($this->result_array) > 0 OR $this->is_fetched)
+		{
+			return $this->result_array();
+		}
+
+		// Define the output
+		$output = array('assoc', 'object');
+
+		// Fetch the result
+		foreach ($output as $type)
+		{
+			// Define the method and handler
+			$res_method  = '_fetch_'.$type;
+			$res_handler = 'result_'.$type;
+			
+			$this->$res_handler = array();
+			$this->_data_seek(0);
+
+			while ($row = $this->$res_method())
+			{
+				$this->{$res_handler}[] = $row;
+			}
+		}
+
+		// Save this as buffer and marked the fetch flag
+		$this->result_array = $this->result_assoc;
+		$this->is_fetched = TRUE;
+
+		return $this->result_assoc;
 	}
 
 	// --------------------------------------------------------------------
@@ -78,6 +140,7 @@ class CI_DB_pdo_result extends CI_DB_result {
 		{
 			return $this->db->display_error('db_unsuported_feature');
 		}
+		
 		return FALSE;
 	}
 
@@ -110,6 +173,7 @@ class CI_DB_pdo_result extends CI_DB_result {
 			{
 				return $this->db->display_error('db_unsuported_feature');
 			}
+
 			return FALSE;
 		}
 	}
@@ -178,6 +242,5 @@ class CI_DB_pdo_result extends CI_DB_result {
 
 }
 
-
 /* 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/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 42329bded..89541e5fa 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -147,22 +147,6 @@ class CI_DB_postgre_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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
@@ -712,4 +696,4 @@ class CI_DB_postgre_driver extends CI_DB {
 
 
 /* End of file postgre_driver.php */
-/* Location: ./system/database/drivers/postgre/postgre_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/postgre/postgre_driver.php */
diff --git a/system/database/drivers/sqlite/sqlite_driver.php b/system/database/drivers/sqlite/sqlite_driver.php
index 28c3caecd..718501b20 100644
--- a/system/database/drivers/sqlite/sqlite_driver.php
+++ b/system/database/drivers/sqlite/sqlite_driver.php
@@ -141,22 +141,6 @@ class CI_DB_sqlite_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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
@@ -667,4 +651,4 @@ class CI_DB_sqlite_driver extends CI_DB {
 
 
 /* End of file sqlite_driver.php */
-/* Location: ./system/database/drivers/sqlite/sqlite_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/sqlite/sqlite_driver.php */
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index 6fd52ef70..9b9038189 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -122,28 +122,23 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Select the database
 	 *
-	 * @access	private called by the base class
-	 * @return	resource
+	 * @param	string	database name
+	 * @return	bool
 	 */
-	function db_select()
+	public function db_select($database = '')
 	{
-		return $this->_execute('USE ' . $this->database);
-	}
+		if ($database === '')
+		{
+			$database = $this->database;
+		}
 
-	// --------------------------------------------------------------------
+		if ($this->_execute('USE '.$database))
+		{
+			$this->database = $database;
+			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;
+		return FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -413,13 +408,18 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * The error message string
 	 *
-	 * @access	private
 	 * @return	string
 	 */
-	function _error_message()
+	protected function _error_message()
 	{
-		$error = array_shift(sqlsrv_errors());
-		return !empty($error['message']) ? $error['message'] : null;
+		$error = sqlsrv_errors();
+		if ( ! is_array($error))
+		{
+			return '';
+		}
+
+		$error = array_shift($error);
+		return isset($error['message']) ? $error['message'] : '';
 	}
 
 	// --------------------------------------------------------------------
@@ -427,13 +427,25 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * The error message number
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	string
 	 */
-	function _error_number()
+	protected function _error_number()
 	{
-		$error = array_shift(sqlsrv_errors());
-		return isset($error['SQLSTATE']) ? $error['SQLSTATE'] : null;
+		$error = sqlsrv_errors();
+		if ( ! is_array($error))
+		{
+			return '';
+		}
+		elseif (isset($error['SQLSTATE']))
+		{
+			return isset($error['code']) ? $error['SQLSTATE'].'/'.$error['code'] : $error['SQLSTATE'];
+		}
+		elseif (isset($error['code']))
+		{
+			return $error['code'];
+		}
+
+		return '';
 	}
 
 	// --------------------------------------------------------------------
@@ -608,4 +620,4 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 
 
 /* End of file mssql_driver.php */
-/* Location: ./system/database/drivers/mssql/mssql_driver.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/mssql/mssql_driver.php */