Merge branch 'develop' of github.com:EllisLab/CodeIgniter into develop

83 files changed, 1498 insertions, 1338 deletions

diff --git a/system/core/Benchmark.php b/system/core/Benchmark.php
index 2fabdf46e..2fabdf46e 100755..100644
--- a/system/core/Benchmark.php
+++ b/system/core/Benchmark.php
diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index b3e984d4d..8159b19f5 100755..100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -73,9 +73,9 @@
  */
 	set_error_handler('_exception_handler');
 
-	if ( ! is_php('5.3'))
+	if ( ! is_php('5.4'))
 	{
-		@set_magic_quotes_runtime(0); // Kill magic quotes
+		@ini_set('magic_quotes_runtime', 0); // Kill magic quotes
 	}
 
 /*
diff --git a/system/core/Common.php b/system/core/Common.php
index 8af7d6323..1708653e7 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -44,13 +44,13 @@ if ( ! function_exists('is_php'))
 	/**
 	 * Determines if the current version of PHP is greater then the supplied value
 	 *
-	 * Since there are a few places where we conditionally test for PHP > 5
+	 * Since there are a few places where we conditionally test for PHP > 5.3
 	 * we'll set a static variable.
 	 *
 	 * @param	string
 	 * @return	bool	TRUE if the current version is $version or higher
 	 */
-	function is_php($version = '5.0.0')
+	function is_php($version = '5.3.0')
 	{
 		static $_is_php;
 		$version = (string) $version;
@@ -233,18 +233,18 @@ if ( ! function_exists('get_config'))
 
 		$file_path = APPPATH.'config/config.php';
 		$found = FALSE;
-		if (file_exists($file_path)) 
+		if (file_exists($file_path))
 		{
 			$found = TRUE;
 			require($file_path);
 		}
 
 		// Is the config file in the environment folder?
-		if (defined(ENVIRONMENT) && file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/config.php'))
+		if (defined('ENVIRONMENT') && file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/config.php'))
 		{
-			require($file_path);			
-		} 
-		elseif ( ! $found) 
+			require($file_path);
+		}
+		elseif ( ! $found)
 		{
 			set_status_header(503);
 			exit('The configuration file does not exist.');
@@ -304,6 +304,32 @@ if ( ! function_exists('config_item'))
 
 // ------------------------------------------------------------------------
 
+if ( ! function_exists('get_mimes'))
+{
+	/**
+	 * Returns the MIME types array from config/mimes.php
+	 *
+	 * @return	array
+	 */
+	function &get_mimes()
+	{
+		static $_mimes = array();
+
+		if (defined('ENVIRONMENT') && is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
+		{
+			$_mimes = include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
+		}
+		elseif (is_file(APPPATH.'config/mimes.php'))
+		{
+			$_mimes = include(APPPATH.'config/mimes.php');
+		}
+
+		return $_mimes;
+	}
+}
+
+// ------------------------------------------------------------------------
+
 if ( ! function_exists('show_error'))
 {
 	/**
diff --git a/system/core/Config.php b/system/core/Config.php
index 3de1bcb96..3de1bcb96 100755..100644
--- a/system/core/Config.php
+++ b/system/core/Config.php
diff --git a/system/core/Exceptions.php b/system/core/Exceptions.php
index 8c32085fe..8c32085fe 100755..100644
--- a/system/core/Exceptions.php
+++ b/system/core/Exceptions.php
diff --git a/system/core/Hooks.php b/system/core/Hooks.php
index 29fd88201..29fd88201 100755..100644
--- a/system/core/Hooks.php
+++ b/system/core/Hooks.php
diff --git a/system/core/Input.php b/system/core/Input.php
index 73f46ba6a..162e40c85 100755..100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -376,14 +376,26 @@ class CI_Input {
 	/**
 	 * Validate IP Address
 	 *
-	 * Updated version suggested by Geert De Deckere
-	 *
 	 * @param	string
+	 * @param	string	'ipv4' or 'ipv6'
 	 * @return	bool
 	 */
-	public function valid_ip($ip)
+	public function valid_ip($ip, $which = '')
 	{
-		return (bool) filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4);
+		switch (strtolower($which))
+		{
+			case 'ipv4':
+				$which = FILTER_FLAG_IPV4;
+				break;
+			case 'ipv6':
+				$which = FILTER_FLAG_IPV6;
+				break;
+			default:
+				$which = NULL;
+				break;
+		}
+
+		return (bool) filter_var($ip, FILTER_VALIDATE_IP, $which);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/core/Lang.php b/system/core/Lang.php
index 3001f1b13..3001f1b13 100755..100644
--- a/system/core/Lang.php
+++ b/system/core/Lang.php
diff --git a/system/core/Loader.php b/system/core/Loader.php
index 09e948714..94739c74a 100644
--- a/system/core/Loader.php
+++ b/system/core/Loader.php
@@ -668,7 +668,7 @@ class CI_Loader {
 	 * @param 	bool
 	 * @return	void
 	 */
-	public function add_package_path($path, $view_cascade=TRUE)
+	public function add_package_path($path, $view_cascade = TRUE)
 	{
 		$path = rtrim($path, '/').'/';
 
diff --git a/system/core/Model.php b/system/core/Model.php
index 9bc9f879f..9bc9f879f 100755..100644
--- a/system/core/Model.php
+++ b/system/core/Model.php
diff --git a/system/core/Output.php b/system/core/Output.php
index b5484ac81..8a0f14e02 100755..100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -64,7 +64,7 @@ class CI_Output {
 	 *
 	 * @var array
 	 */
-	public $mime_types =	array();
+	public $mimes =		array();
 
 	/**
 	 * Mime-type for the current page
@@ -110,14 +110,7 @@ class CI_Output {
 		$this->_zlib_oc = (bool) @ini_get('zlib.output_compression');
 
 		// Get mime types for later
-		if (defined('ENVIRONMENT') && file_exists(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
-		{
-			$this->mime_types = include APPPATH.'config/'.ENVIRONMENT.'/mimes.php';
-		}
-		else
-		{
-			$this->mime_types = include APPPATH.'config/mimes.php';
-		}
+		$this->mimes =& get_mimes();
 
 		log_message('debug', 'Output Class Initialized');
 	}
@@ -213,16 +206,16 @@ class CI_Output {
 	 * @param	string	extension of the file we're outputting
 	 * @return	void
 	 */
-	public function set_content_type($mime_type)
+	public function set_content_type($mime_type, $charset = NULL)
 	{
 		if (strpos($mime_type, '/') === FALSE)
 		{
 			$extension = ltrim($mime_type, '.');
 
 			// Is this extension supported?
-			if (isset($this->mime_types[$extension]))
+			if (isset($this->mimes[$extension]))
 			{
-				$mime_type =& $this->mime_types[$extension];
+				$mime_type =& $this->mimes[$extension];
 
 				if (is_array($mime_type))
 				{
@@ -233,7 +226,13 @@ class CI_Output {
 		
 		$this->mime_type = $mime_type;
 
-		$header = 'Content-Type: '.$mime_type;
+		if (empty($charset))
+		{
+			$charset = config_item('charset');
+		}
+
+		$header = 'Content-Type: '.$mime_type
+			.(empty($charset) ? NULL : '; charset='.strtolower($charset));
 
 		$this->headers[] = array($header, TRUE);
 		return $this;
@@ -388,7 +387,7 @@ class CI_Output {
 
 		if ($this->parse_exec_vars === TRUE)
 		{
-			$memory	= function_exists('memory_get_usage') ? round(memory_get_usage()/1024/1024, 2).'MB' : '0';
+			$memory	= round(memory_get_usage() / 1024 / 1024, 2).'MB';
 
 			$output = str_replace(array('{elapsed_time}', '{memory_usage}'), array($elapsed, $memory), $output);
 		}
diff --git a/system/core/Router.php b/system/core/Router.php
index 5bc053045..5bc053045 100755..100644
--- a/system/core/Router.php
+++ b/system/core/Router.php
diff --git a/system/core/Security.php b/system/core/Security.php
index 4593a1090..4593a1090 100755..100644
--- a/system/core/Security.php
+++ b/system/core/Security.php
diff --git a/system/core/URI.php b/system/core/URI.php
index a575bc36e..a997525ee 100755..100644
--- a/system/core/URI.php
+++ b/system/core/URI.php
@@ -119,7 +119,7 @@ class CI_URI {
 			}
 
 			// No PATH_INFO?... What about QUERY_STRING?
-			$path = (isset($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : @getenv('QUERY_STRING');
+			$path = isset($_SERVER['QUERY_STRING']) ? $_SERVER['QUERY_STRING'] : @getenv('QUERY_STRING');
 			if (trim($path, '/') !== '')
 			{
 				$this->_set_uri_string($path);
@@ -163,7 +163,7 @@ class CI_URI {
 	 * @param 	string
 	 * @return	void
 	 */
-	public function _set_uri_string($str)
+	protected function _set_uri_string($str)
 	{
 		// Filter out control characters
 		$str = remove_invisible_characters($str, FALSE);
@@ -177,8 +177,8 @@ class CI_URI {
 	/**
 	 * Detects the URI
 	 *
-	 * This function will detect the URI automatically and fix the query string
-	 * if necessary.
+	 * This function will detect the URI automatically
+	 * and fix the query string if necessary.
 	 *
 	 * @return	string
 	 */
@@ -189,23 +189,27 @@ class CI_URI {
 			return '';
 		}
 
-		$uri = $_SERVER['REQUEST_URI'];
-		if (strpos($uri, $_SERVER['SCRIPT_NAME']) === 0)
+		if (strpos($_SERVER['REQUEST_URI'], $_SERVER['SCRIPT_NAME']) === 0)
 		{
-			$uri = substr($uri, strlen($_SERVER['SCRIPT_NAME']));
+			$uri = substr($_SERVER['REQUEST_URI'], strlen($_SERVER['SCRIPT_NAME']));
 		}
-		elseif (strpos($uri, dirname($_SERVER['SCRIPT_NAME'])) === 0)
+		elseif (strpos($_SERVER['REQUEST_URI'], dirname($_SERVER['SCRIPT_NAME'])) === 0)
 		{
-			$uri = substr($uri, strlen(dirname($_SERVER['SCRIPT_NAME'])));
+			$uri = substr($_SERVER['REQUEST_URI'], strlen(dirname($_SERVER['SCRIPT_NAME'])));
+		}
+		else
+		{
+			$uri = $_SERVER['REQUEST_URI'];
 		}
 
 		// This section ensures that even on servers that require the URI to be in the query string (Nginx) a correct
 		// URI is found, and also fixes the QUERY_STRING server var and $_GET array.
-		if (strncmp($uri, '?/', 2) === 0)
+		if (strpos($uri, '?/') === 0)
 		{
 			$uri = substr($uri, 2);
 		}
-		$parts = preg_split('#\?#i', $uri, 2);
+
+		$parts = explode('?', $uri, 2);
 		$uri = $parts[0];
 		if (isset($parts[1]))
 		{
@@ -223,7 +227,7 @@ class CI_URI {
 			return '/';
 		}
 
-		$uri = parse_url($uri, PHP_URL_PATH);
+		$uri = parse_url('pseudo://hostname/'.$uri, PHP_URL_PATH);
 
 		// Do some final cleaning of the URI and return it
 		return str_replace(array('//', '../'), '/', trim($uri, '/'));
diff --git a/system/database/DB.php b/system/database/DB.php
index 00d14b43e..00d14b43e 100755..100644
--- a/system/database/DB.php
+++ b/system/database/DB.php
diff --git a/system/database/DB_cache.php b/system/database/DB_cache.php
index 14f3c21bc..ba9110382 100644
--- a/system/database/DB_cache.php
+++ b/system/database/DB_cache.php
@@ -99,7 +99,7 @@ class CI_DB_Cache {
 		$segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
 		$filepath = $this->db->cachedir.$segment_one.'+'.$segment_two.'/'.md5($sql);
 
-		if (FALSE === ($cachedata = read_file($filepath)))
+		if (FALSE === ($cachedata = file_get_contents($filepath)))
 		{
 			return FALSE;
 		}
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 39c19cdf7..d056bdb90 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -596,35 +596,53 @@ abstract class CI_DB_driver {
 	 */
 	public function compile_binds($sql, $binds)
 	{
-		if (strpos($sql, $this->bind_marker) === FALSE)
+		if (empty($binds) OR empty($this->bind_marker) OR strpos($sql, $this->bind_marker) === FALSE)
 		{
 			return $sql;
 		}
-
-		if ( ! is_array($binds))
+		elseif ( ! is_array($binds))
 		{
 			$binds = array($binds);
+			$bind_count = 1;
+		}
+		else
+		{
+			// Make sure we're using numeric keys
+			$binds = array_values($binds);
+			$bind_count = count($binds);
 		}
 
-		// Get the sql segments around the bind markers
-		$segments = explode($this->bind_marker, $sql);
+		// We'll need the marker length later
+		$ml = strlen($this->bind_marker);
 
-		// The count of bind should be 1 less then the count of segments
-		// If there are more bind arguments trim it down
-		if (count($binds) >= count($segments))
+		// Make sure not to replace a chunk inside a string that happens to match the bind marker
+		if ($c = preg_match_all("/'[^']*'/i", $sql, $matches))
+		{
+			$c = preg_match_all('/'.preg_quote($this->bind_marker).'/i',
+				str_replace($matches[0],
+					str_replace($this->bind_marker, str_repeat(' ', $ml), $matches[0]),
+					$sql, $c),
+				$matches, PREG_OFFSET_CAPTURE);
+
+			// Bind values' count must match the count of markers in the query
+			if ($bind_count !== $c)
+			{
+				return $sql;
+			}
+		}
+		elseif (($c = preg_match_all('/'.preg_quote($this->bind_marker).'/i', $sql, $matches, PREG_OFFSET_CAPTURE)) !== $bind_count)
 		{
-			$binds = array_slice($binds, 0, count($segments)-1);
+			return $sql;
 		}
 
-		// Construct the binded query
-		$result = $segments[0];
-		$i = 0;
-		foreach ($binds as $bind)
+		do
 		{
-			$result .= $this->escape($bind).$segments[++$i];
+			$c--;
+			$sql = substr_replace($sql, $this->escape($binds[$c]), $matches[0][$c][1], $ml);
 		}
+		while ($c !== 0);
 
-		return $result;
+		return $sql;
 	}
 
 	// --------------------------------------------------------------------
@@ -934,8 +952,8 @@ abstract class CI_DB_driver {
 	 *
 	 * This function escapes column and table names
 	 *
-	 * @param	string
-	 * @return	string
+	 * @param	mixed
+	 * @return	mixed
 	 */
 	public function escape_identifiers($item)
 	{
@@ -943,25 +961,39 @@ abstract class CI_DB_driver {
 		{
 			return $item;
 		}
-
-		foreach ($this->_reserved_identifiers as $id)
+		elseif (is_array($item))
 		{
-			if (strpos($item, '.'.$id) !== FALSE)
+			foreach ($item as $key => $value)
 			{
-				$item = str_replace('.', $this->_escape_char.'.', $item);
+				$item[$key] = $this->escape_identifiers($value);
+			}
+
+			return $item;
+		}
+
+		static $preg_ec = array();
 
-				// remove duplicates if the user already included the escape
-				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item);
+		if (empty($preg_ec))
+		{
+			if (is_array($this->_escape_char))
+			{
+				$preg_ec = array(preg_quote($this->_escape_char[0]), preg_quote($this->_escape_char[1]));
+			}
+			else
+			{
+				$preg_ec[0] = $preg_ec[1] = preg_quote($this->_escape_char);
 			}
 		}
 
-		if (strpos($item, '.') !== FALSE)
+		foreach ($this->_reserved_identifiers as $id)
 		{
-			$item = str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item);
+			if (strpos($item, '.'.$id) !== FALSE)
+			{
+				return preg_replace('/'.$preg_ec[0].'?([^'.$preg_ec[1].'\.]+)'.$preg_ec[1].'?\./i', $preg_ec[0].'$1'.$preg_ec[1].'.', $item);
+			}
 		}
 
-		// remove duplicates if the user already included the escape
-		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $this->_escape_char.$item.$this->_escape_char);
+		return preg_replace('/'.$preg_ec[0].'?([^'.$preg_ec[1].'\.]+)'.$preg_ec[1].'?(\.)?/i', $preg_ec[0].'$1'.$preg_ec[1].'$2', $item);
 	}
 
 	// --------------------------------------------------------------------
@@ -1048,7 +1080,7 @@ abstract class CI_DB_driver {
 	 */
 	protected function _has_operator($str)
 	{
-		return (bool) preg_match('/(\s|<|>|!|=|IS NULL|IS NOT NULL)/i', trim($str));
+		return (bool) preg_match('/(\s|<|>|!|=|IS NULL|IS NOT NULL|BETWEEN)/i', trim($str));
 	}
 
 	// --------------------------------------------------------------------
@@ -1286,36 +1318,63 @@ abstract class CI_DB_driver {
 			$escaped_array = array();
 			foreach ($item as $k => $v)
 			{
-				$escaped_array[$this->protect_identifiers($k)] = $this->protect_identifiers($v);
+				$escaped_array[$this->protect_identifiers($k)] = $this->protect_identifiers($v, $prefix_single, $protect_identifiers, $field_exists);
 			}
 
 			return $escaped_array;
 		}
 
+		// This is basically a bug fix for queries that use MAX, MIN, etc.
+		// If a parenthesis is found we know that we do not need to
+		// escape the data or add a prefix. There's probably a more graceful
+		// way to deal with this, but I'm not thinking of it -- Rick
+		if (strpos($item, '(') !== FALSE)
+		{
+			return $item;
+		}
+
 		// Convert tabs or multiple spaces into single spaces
-		$item = preg_replace('/[\t ]+/', ' ', $item);
+		$item = preg_replace('/\s+/', ' ', $item);
+
+		static $preg_ec = array();
+
+		if (empty($preg_ec))
+		{
+			if (is_array($this->_escape_char))
+			{
+				$preg_ec = array(preg_quote($this->_escape_char[0]), preg_quote($this->_escape_char[1]));
+			}
+			else
+			{
+				$preg_ec[0] = $preg_ec[1] = preg_quote($this->_escape_char);
+			}
+		}
 
 		// If the item has an alias declaration we remove it and set it aside.
 		// Basically we remove everything to the right of the first space
-		if (strpos($item, ' ') !== FALSE)
+		preg_match('/^(('.$preg_ec[0].'[^'.$preg_ec[1].']+'.$preg_ec[1].')|([^'.$preg_ec[0].'][^\s]+))( AS)*(.+)*$/i', $item, $matches);
+
+		if (isset($matches[4]))
 		{
-			$alias = strstr($item, ' ');
-			$item = substr($item, 0, - strlen($alias));
+			$item = $matches[1];
+
+			// Escape the alias, if needed
+			if ($protect_identifiers === TRUE)
+			{
+				$alias = empty($matches[5])
+					? ' '.$this->escape_identifiers(ltrim($matches[4]))
+					: $matches[4].' '.$this->escape_identifiers(ltrim($matches[5]));
+			}
+			else
+			{
+				$alias = $matches[4].$matches[5];
+			}
 		}
 		else
 		{
 			$alias = '';
 		}
 
-		// This is basically a bug fix for queries that use MAX, MIN, etc.
-		// If a parenthesis is found we know that we do not need to
-		// escape the data or add a prefix. There's probably a more graceful
-		// way to deal with this, but I'm not thinking of it -- Rick
-		if (strpos($item, '(') !== FALSE)
-		{
-			return $item.$alias;
-		}
-
 		// Break the string apart if it contains periods, then insert the table prefix
 		// in the correct location, assuming the period doesn't indicate that we're dealing
 		// with an alias. While we're at it, we will escape the components
diff --git a/system/database/DB_forge.php b/system/database/DB_forge.php
index ff5eb3fe6..9b7639289 100644
--- a/system/database/DB_forge.php
+++ b/system/database/DB_forge.php
@@ -72,6 +72,11 @@ abstract class CI_DB_forge {
 			return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
 		}
 
+		if ( ! empty($this->db->data_cache['db_names']))
+		{
+			$this->db->data_cache['db_names'][] = $db_name;
+		}
+
 		return TRUE;
 	}
 
@@ -99,6 +104,15 @@ abstract class CI_DB_forge {
 			return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
 		}
 
+		if ( ! empty($this->db->data_cache['db_names']))
+		{
+			$key = array_search(strtolower($db_name), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				unset($this->db->data_cache['db_names'][$key]);
+			}
+		}
+
 		return TRUE;
 	}
 
@@ -209,7 +223,18 @@ abstract class CI_DB_forge {
 
 		$sql = $this->_create_table($this->db->dbprefix.$table, $this->fields, $this->primary_keys, $this->keys, $if_not_exists);
 		$this->_reset();
-		return is_bool($sql) ? $sql : $this->db->query($sql);
+
+		if (is_bool($sql))
+		{
+			return $sql;
+		}
+
+		if (($result = $this->db->query($sql)) !== FALSE && ! empty($this->db->data_cache['table_names']))
+		{
+			$this->db->data_cache['table_names'][] = $$this->db->dbprefix.$table;
+		}
+
+		return $result;
 	}
 
 	// --------------------------------------------------------------------
@@ -231,7 +256,19 @@ abstract class CI_DB_forge {
 			return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
 		}
 
-		return $this->db->query(sprintf($this->_drop_table, $this->db->escape_identifiers($this->db->dbprefix.$table_name)));
+		$result = $this->db->query(sprintf($this->_drop_table, $this->db->escape_identifiers($this->db->dbprefix.$table_name)));
+
+		// Update table list cache
+		if ($result && ! empty($this->db->data_cache['table_names']))
+		{
+			$key = array_search(strtolower($this->db->dbprefix.$table_name), array_map('strtolower', $this->db->data_cache['table_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				unset($this->db->data_cache['table_names'][$key]);
+			}
+		}
+
+		return $result;
 	}
 
 	// --------------------------------------------------------------------
@@ -255,10 +292,21 @@ abstract class CI_DB_forge {
 			return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
 		}
 
-		return $this->db->query(sprintf($this->_rename_table,
+		$result = $this->db->query(sprintf($this->_rename_table,
 						$this->db->escape_identifiers($this->db->dbprefix.$table_name),
 						$this->db->escape_identifiers($this->db->dbprefix.$new_table_name))
 					);
+
+		if ($result && ! empty($this->db->data_cache['table_names']))
+		{
+			$key = array_search(strtolower($this->db->dbprefix.$table_name), array_map('strtolower', $this->db->data_cache['table_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				$this->db->data_cache['table_names'][$key] = $this->db->dbprefix.$new_table_name;
+			}
+		}
+
+		return $result;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 7a0ea0c30..488b294e4 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -53,7 +53,6 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	protected $qb_keys			= array();
 	protected $qb_limit			= FALSE;
 	protected $qb_offset			= FALSE;
-	protected $qb_order			= FALSE;
 	protected $qb_orderby			= array();
 	protected $qb_set			= array();
 	protected $qb_wherein			= array();
@@ -84,6 +83,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 * Generates the SELECT portion of the query
 	 *
 	 * @param	string
+	 * @param	mixed
 	 * @return	object
 	 */
 	public function select($select = '*', $escape = NULL)
@@ -93,6 +93,9 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$select = explode(',', $select);
 		}
 
+		// If the escape value was not set will will base it on the global setting
+		is_bool($escape) OR $escape = $this->_protect_identifiers;
+
 		foreach ($select as $val)
 		{
 			$val = trim($val);
@@ -321,15 +324,16 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 * @param	string
 	 * @param	string	the join condition
 	 * @param	string	the type of join
+	 * @param	string	wether not to try to escape identifiers
 	 * @return	object
 	 */
-	public function join($table, $cond, $type = '')
+	public function join($table, $cond, $type = '', $escape = TRUE)
 	{
 		if ($type !== '')
 		{
 			$type = strtoupper(trim($type));
 
-			if ( ! in_array($type, array('LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER')))
+			if ( ! in_array($type, array('LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER'), TRUE))
 			{
 				$type = '';
 			}
@@ -343,12 +347,39 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 		// in the protect_identifiers to know whether to add a table prefix
 		$this->_track_aliases($table);
 
-		// Strip apart the condition and protect the identifiers
-		if (preg_match('/([\[\w\.]+)([\W\s]+)(.+)/', $cond, $match))
+		// Split multiple conditions
+		if ($escape === TRUE && preg_match_all('/\sAND\s|\sOR\s/i', $cond, $m, PREG_SET_ORDER | PREG_OFFSET_CAPTURE))
+		{
+			$newcond = '';
+			$m[0][] = array('', strlen($cond));
+
+			for ($i = 0, $c = count($m[0]), $s = 0;
+				$i < $c;
+				$s += $m[0][$i][1] + strlen($m[0][$i][0]), $i++)
+			{
+				$temp = substr($cond, $s, $m[0][$i][1]);
+
+				$newcond .= preg_match('/([\[\w\.-]+)([\W\s]+)(.+)/i', $temp, $match)
+						? $this->protect_identifiers($match[1]).$match[2].$this->protect_identifiers($match[3])
+						: $temp;
+
+				$newcond .= $m[0][$i][0];
+			}
+
+			$cond = $newcond;
+		}
+		// Split apart the condition and protect the identifiers
+		elseif ($escape === TRUE && preg_match('/([\[\w\.-]+)([\W\s]+)(.+)/i', $cond, $match))
 		{
 			$cond = $this->protect_identifiers($match[1]).$match[2].$this->protect_identifiers($match[3]);
 		}
 
+		// Do we want to escape the table name?
+		if ($escape === TRUE)
+		{
+			$table = $this->protect_identifiers($table, TRUE, NULL, FALSE);
+		}
+
 		// Assemble the JOIN statement
 		$this->qb_join[] = $join = $type.'JOIN '.$this->protect_identifiers($table, TRUE, NULL, FALSE).' ON '.$cond;
 
@@ -371,6 +402,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 *
 	 * @param	mixed
 	 * @param	mixed
+	 * @param	bool
 	 * @return	object
 	 */
 	public function where($key, $value = NULL, $escape = TRUE)
@@ -388,6 +420,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 *
 	 * @param	mixed
 	 * @param	mixed
+	 * @param	bool
 	 * @return	object
 	 */
 	public function or_where($key, $value = NULL, $escape = TRUE)
@@ -405,6 +438,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 * @param	mixed
 	 * @param	mixed
 	 * @param	string
+	 * @param	mixed
 	 * @return	object
 	 */
 	protected function _where($key, $value = NULL, $type = 'AND ', $escape = NULL)
@@ -417,15 +451,16 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 		}
 
 		// If the escape value was not set will will base it on the global setting
-		if ( ! is_bool($escape))
-		{
-			$escape = $this->_protect_identifiers;
-		}
+		$escape = $this->_protect_identifiers;
 
 		foreach ($key as $k => $v)
 		{
 			$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0) ? '' : $type;
 
+			$k = $this->_has_operator($k)
+				? $this->protect_identifiers(substr($k, 0, strpos(rtrim($k), ' ')), FALSE, $escape).strchr(rtrim($k), ' ')
+				: $this->protect_identifiers($k, FALSE, $escape);
+
 			if (is_null($v) && ! $this->_has_operator($k))
 			{
 				// value appears not to have been set, assign the test to IS NULL
@@ -436,7 +471,6 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			{
 				if ($escape === TRUE)
 				{
-					$k = $this->protect_identifiers($k, FALSE, $escape);
 					$v = ' '.$this->escape($v);
 				}
 
@@ -445,10 +479,6 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 					$k .= ' = ';
 				}
 			}
-			else
-			{
-				$k = $this->protect_identifiers($k, FALSE, $escape);
-			}
 
 			$this->qb_where[] = $prefix.$k.$v;
 			if ($this->qb_caching === TRUE)
@@ -547,7 +577,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	{
 		if ($key === NULL OR $values === NULL)
 		{
-			return;
+			return $this;
 		}
 
 		$type = $this->_group_get_type($type);
@@ -853,6 +883,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 *
 	 * @param	string
 	 * @param	string
+	 * @param	bool
 	 * @return	object
 	 */
 	public function having($key, $value = '', $escape = TRUE)
@@ -869,6 +900,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 *
 	 * @param	string
 	 * @param	string
+	 * @param	bool
 	 * @return	object
 	 */
 	public function or_having($key, $value = '', $escape = TRUE)
@@ -885,6 +917,8 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 *
 	 * @param	string
 	 * @param	string
+	 * @param	string
+	 * @param	bool
 	 * @return	object
 	 */
 	protected function _having($key, $value = '', $type = 'AND ', $escape = TRUE)
@@ -943,7 +977,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 		}
 		elseif (trim($direction) !== '')
 		{
-			$direction = (in_array(strtoupper(trim($direction)), array('ASC', 'DESC'), TRUE)) ? ' '.$direction : ' ASC';
+			$direction = in_array(strtoupper(trim($direction)), array('ASC', 'DESC'), TRUE) ? ' '.$direction : ' ASC';
 		}
 
 
@@ -955,7 +989,9 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 				$part = trim($part);
 				if ( ! in_array($part, $this->qb_aliased_tables))
 				{
-					$part = $this->protect_identifiers(trim($part));
+					$part = preg_match('/^(.+)\s+(ASC|DESC)$/i', $part, $matches)
+						? $this->protect_identifiers(rtrim($matches[1])).' '.$matches[2]
+						: $this->protect_identifiers($part);
 				}
 
 				$temp[] = $part;
@@ -963,12 +999,11 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 
 			$orderby = implode(', ', $temp);
 		}
-		elseif ($direction !== $this->_random_keyword)
+		elseif ($direction !== $this->_random_keyword && $escape === TRUE)
 		{
-			if ($escape === TRUE)
-			{
-				$orderby = $this->protect_identifiers($orderby);
-			}
+			$orderby = preg_match('/^(.+)\s+(ASC|DESC)$/i', $orderby, $matches)
+				? $this->protect_identifiers(rtrim($matches[1])).' '.$matches[2]
+				: $this->protect_identifiers($orderby);
 		}
 
 		$this->qb_orderby[] = $orderby_statement = $orderby.$direction;
@@ -995,7 +1030,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	{
 		$this->qb_limit = (int) $value;
 
-		if ( ! is_null($offset))
+		if ( ! empty($offset))
 		{
 			$this->qb_offset = (int) $offset;
 		}
@@ -1070,7 +1105,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->from($table);
 		}
 
-		$select =  $this->_compile_select();
+		$select = $this->_compile_select();
 
 		if ($reset === TRUE)
 		{
@@ -1093,7 +1128,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 * @param	string	the offset clause
 	 * @return	object
 	 */
-	public function get($table = '', $limit = null, $offset = null)
+	public function get($table = '', $limit = NULL, $offset = NULL)
 	{
 		if ($table !== '')
 		{
@@ -1101,7 +1136,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->from($table);
 		}
 
-		if ( ! is_null($limit))
+		if ( ! empty($limit))
 		{
 			$this->limit($limit, $offset);
 		}
@@ -1166,7 +1201,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->where($where);
 		}
 
-		if ( ! is_null($limit))
+		if ( ! empty($limit))
 		{
 			$this->limit($limit, $offset);
 		}
@@ -1275,11 +1310,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 
 			ksort($row); // puts $row in the same order as our keys
 
-			if ($escape === FALSE)
-			{
-				$this->qb_set[] =  '('.implode(',', $row).')';
-			}
-			else
+			if ($escape !== FALSE)
 			{
 				$clean = array();
 				foreach ($row as $value)
@@ -1287,8 +1318,10 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 					$clean[] = $this->escape($value);
 				}
 
-				$this->qb_set[] =  '('.implode(',', $clean).')';
+				$row = $clean;
 			}
+
+			$this->qb_set[] =  '('.implode(',', $row).')';
 		}
 
 		foreach ($keys as $k)
@@ -1475,6 +1508,24 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	// --------------------------------------------------------------------
 
 	/**
+	 * From Tables
+	 *
+	 * This public function implicitly groups FROM tables so there is no confusion
+	 * about operator precedence in harmony with SQL standards
+	 *
+	 * @param       array
+	 * @return      string
+	 */
+	protected function _from_tables($tables)
+	{
+		is_array($tables) OR $tables = array($tables);
+
+		return (count($tables) === 1) ? $tables[0] : '('.implode(', ', $tables).')';
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Get UPDATE query string
 	 *
 	 * Compiles an update query and returns the sql
@@ -1535,7 +1586,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->where($where);
 		}
 
-		if ($limit != NULL)
+		if ( ! empty($limit))
 		{
 			$this->limit($limit);
 		}
@@ -1856,7 +1907,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->where($where);
 		}
 
-		if ($limit != NULL)
+		if ( ! empty($limit))
 		{
 			$this->limit($limit);
 		}
@@ -1897,7 +1948,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 
 		return 'DELETE FROM '.$table
 			.(count($conditions) > 0 ? ' WHERE '.implode(' AND ', $conditions) : '')
-			.($limit ? ' LIMIT '.$limit : '');
+			.($limit ? ' LIMIT '.(int) $limit : '');
 	}
 
 	// --------------------------------------------------------------------
@@ -1967,7 +2018,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 		if (strpos($table, ' ') !== FALSE)
 		{
 			// if the alias is written with the AS keyword, remove it
-			$table = preg_replace('/ AS /i', ' ', $table);
+			$table = preg_replace('/\s+AS\s+/i', ' ', $table);
 
 			// Grab the alias
 			$table = trim(strrchr($table, ' '));
@@ -2070,10 +2121,6 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 		if (count($this->qb_orderby) > 0)
 		{
 			$sql .= "\nORDER BY ".implode(', ', $this->qb_orderby);
-			if ($this->qb_order !== FALSE)
-			{
-				$sql .= ($this->qb_order === 'desc') ? ' DESC' : ' ASC';
-			}
 		}
 
 		// Write the "LIMIT" portion of the query
@@ -2303,8 +2350,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 					'qb_no_escape'		=> array(),
 					'qb_distinct'		=> FALSE,
 					'qb_limit'		=> FALSE,
-					'qb_offset'		=> FALSE,
-					'qb_order'		=> FALSE
+					'qb_offset'		=> FALSE
 					)
 				);
 	}
@@ -2327,8 +2373,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			'qb_like'	=> array(),
 			'qb_orderby'	=> array(),
 			'qb_keys'	=> array(),
-			'qb_limit'	=> FALSE,
-			'qb_order'	=> FALSE
+			'qb_limit'	=> FALSE
 			)
 		);
 	}
diff --git a/system/database/DB_utility.php b/system/database/DB_utility.php
index 02c921834..6a3b40779 100644
--- a/system/database/DB_utility.php
+++ b/system/database/DB_utility.php
@@ -35,7 +35,6 @@
 abstract class CI_DB_utility extends CI_DB_forge {
 
 	public $db;
-	public $data_cache		= array();
 
 	// Platform specific SQL strings
 	// Just setting those defaults to FALSE as they are mostly MySQL-specific
@@ -60,29 +59,29 @@ abstract class CI_DB_utility extends CI_DB_forge {
 	public function list_databases()
 	{
 		// Is there a cached result?
-		if (isset($this->data_cache['db_names']))
+		if (isset($this->db->data_cache['db_names']))
 		{
-			return $this->data_cache['db_names'];
+			return $this->db->data_cache['db_names'];
 		}
 		elseif ($this->_list_databases === FALSE)
 		{
 			return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
 		}
 
-		$this->data_cache['db_names'] = array();
+		$this->db->data_cache['db_names'] = array();
 
 		$query = $this->db->query($this->_list_databases);
 		if ($query === FALSE)
 		{
-			return $this->data_cache['db_names'];
+			return $this->db->data_cache['db_names'];
 		}
 
 		for ($i = 0, $c = count($query); $i < $c; $i++)
 		{
-			$this->data_cache['db_names'] = current($query[$i]);
+			$this->db->data_cache['db_names'] = current($query[$i]);
 		}
 
-		return $this->data_cache['db_names'];
+		return $this->db->data_cache['db_names'];
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/cubrid/cubrid_driver.php b/system/database/drivers/cubrid/cubrid_driver.php
index 6b9286fa0..6b67b7546 100644
--- a/system/database/drivers/cubrid/cubrid_driver.php
+++ b/system/database/drivers/cubrid/cubrid_driver.php
@@ -396,27 +396,6 @@ class CI_DB_cubrid_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	array
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Update_Batch statement
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
diff --git a/system/database/drivers/cubrid/cubrid_forge.php b/system/database/drivers/cubrid/cubrid_forge.php
index fb9716226..d328aa241 100644
--- a/system/database/drivers/cubrid/cubrid_forge.php
+++ b/system/database/drivers/cubrid/cubrid_forge.php
@@ -60,8 +60,10 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '');
+
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR $sql .= ' '.$this->db->escape_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
@@ -69,7 +71,7 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 
 					if ( ! empty($attributes['CONSTRAINT']))
 					{
-						switch ($attributes['TYPE'])
+						switch (strtolower($attributes['TYPE']))
 						{
 							case 'decimal':
 							case 'float':
@@ -98,10 +100,23 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 				}
 			 */
 
-				$sql .= (isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '')
-					.(( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE) ? ' UNIQUE' : '');
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
+
+				if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+				{
+					$sql .= ' UNIQUE';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -142,8 +157,8 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 		// If there is a PK defined
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->protect_identifiers('pk_'.$table.'_'.implode('_', $primary_keys));
-			$sql .= ",\n\tCONSTRAINT ".$key_name.' PRIMARY KEY('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers('pk_'.$table.'_'.implode('_', $primary_keys));
+			$sql .= ",\n\tCONSTRAINT ".$key_name.' PRIMARY KEY('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -152,12 +167,12 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 			{
 				if (is_array($key))
 				{
-					$key_name = $this->db->protect_identifiers('idx_'.$table.implode('_', $key));
-					$key = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers('idx_'.$table.implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers('idx_'.$table.$key);
+					$key_name = $this->db->escape_identifiers('idx_'.$table.$key);
 					$key = array($key_name);
 				}
 
@@ -184,16 +199,16 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/cubrid/cubrid_utility.php b/system/database/drivers/cubrid/cubrid_utility.php
index c8cee99b6..ea8feb4e2 100644
--- a/system/database/drivers/cubrid/cubrid_utility.php
+++ b/system/database/drivers/cubrid/cubrid_utility.php
@@ -41,12 +41,12 @@ class CI_DB_cubrid_utility extends CI_DB_utility {
 	 */
 	public function list_databases()
 	{
-		if (isset($this->data_cache['db_names']))
+		if (isset($this->db->data_cache['db_names']))
 		{
-			return $this->data_cache['db_names'];
+			return $this->db->data_cache['db_names'];
 		}
 
-		return $this->data_cache['db_names'] = cubrid_list_dbs($this->db->conn_id);
+		return $this->db->data_cache['db_names'] = cubrid_list_dbs($this->db->conn_id);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/interbase/interbase_driver.php b/system/database/drivers/interbase/interbase_driver.php
index 8cbbfa17d..5a03607ee 100644
--- a/system/database/drivers/interbase/interbase_driver.php
+++ b/system/database/drivers/interbase/interbase_driver.php
@@ -324,13 +324,7 @@ class CI_DB_interbase_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		//Interbase/Firebird doesn't like grouped tables
-		return implode(', ', $tables);
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/interbase/interbase_forge.php b/system/database/drivers/interbase/interbase_forge.php
index 5470179a1..d1b006e80 100644
--- a/system/database/drivers/interbase/interbase_forge.php
+++ b/system/database/drivers/interbase/interbase_forge.php
@@ -67,6 +67,14 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 		{
 			return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
 		}
+		elseif ( ! empty($this->db->data_cache['db_names']))
+		{
+			$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				unset($this->db->data_cache['db_names'][$key]);
+			}
+		}
 
 		return TRUE;
 	}
@@ -87,7 +95,7 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 	{
 		$sql = 'CREATE TABLE ';
 
-		$sql .= $this->db->protect_identifiers($table)."(";
+		$sql .= $this->db->escape_identifiers($table).'(';
 		$current_field_count = 0;
 
 		foreach ($fields as $field => $attributes)
@@ -97,41 +105,30 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 			// entered the field information, so we'll simply add it to the list
 			if (is_numeric($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);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
 
-				if (array_key_exists('CONSTRAINT', $attributes))
-				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
-				}
-
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -146,30 +143,23 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$primary_keys = $this->db->escape_identifiers($primary_keys);
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tUNIQUE (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tUNIQUE (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -191,31 +181,11 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 	 */
 	protected 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);
-
-		$sql .= " {$column_definition}";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"{$default_value}\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			$sql .= ' AFTER ' . $this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
+			.' '.$column_definition
+			.($default_value !== '' ? ' DEFAULT "'.$default_value.'"' : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index 697b2fd28..47dc55844 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -43,7 +43,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	public $dbdriver = 'mssql';
 
 	// The character used for escaping
-	protected $_escape_char = '';
+	protected $_escape_char = '"';
 
 	// clause and character used for LIKE escape sequences
 	protected $_like_escape_str = " ESCAPE '%s' ";
@@ -57,19 +57,37 @@ class CI_DB_mssql_driver extends CI_DB {
 	protected $_count_string = 'SELECT COUNT(*) AS ';
 	protected $_random_keyword = ' NEWID()';
 
-	/**
-	 * Non-persistent database connection
+	// MSSQL-specific properties
+	protected $_quoted_identifier = TRUE;
+
+	/*
+	 * Constructor
 	 *
-	 * @return	resource
+	 * Appends the port number to the hostname, if needed.
+	 *
+	 * @param	array
+	 * @return	void
 	 */
-	public function db_connect()
+	public function __construct($params)
 	{
+		parent::__construct($params);
+
 		if ( ! empty($this->port))
 		{
-			$this->hostname .= ','.$this->port;
+			$this->hostname .= (DIRECTORY_SEPARATOR === '\\' ? ',' : ':').$this->port;
 		}
+	}
+
+	// --------------------------------------------------------------------
 
-		return @mssql_connect($this->hostname, $this->username, $this->password);
+	/**
+	 * Non-persistent database connection
+	 *
+	 * @return	resource
+	 */
+	public function db_connect()
+	{
+		return $this->_mssql_connect();
 	}
 
 	// --------------------------------------------------------------------
@@ -81,12 +99,35 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function db_pconnect()
 	{
-		if ( ! empty($this->port))
+		return $this->_mssql_connect(TRUE);
+	}
+
+	// --------------------------------------------------------------------
+
+	/*
+	 * MSSQL Connect
+	 *
+	 * @param	bool
+	 * @return	resource
+	 */
+	protected function _mssql_connect($persistent = FALSE)
+	{
+		$conn_id = ($persistent)
+				? @mssql_pconnect($this->hostname, $this->username, $this->password)
+				: @mssql_connect($this->hostname, $this->username, $this->password);
+
+		if ( ! $conn_id)
 		{
-			$this->hostname .= ','.$this->port;
+			return FALSE;
 		}
 
-		return @mssql_pconnect($this->hostname, $this->username, $this->password);
+		// Determine how identifiers are escaped
+		$query = $this->query('SELECT CASE WHEN (@@OPTIONS | 256) = @@OPTIONS THEN 1 ELSE 0 END AS qi');
+		$query = $query->row_array();
+		$this->_quoted_identifier = empty($query) ? FALSE : (bool) $query->qi;
+		$this->_escape_char = ($this->_quoted_identifier) ? '"' : array('[', ']');
+
+		return $conn_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -106,7 +147,7 @@ class CI_DB_mssql_driver extends CI_DB {
 
 		// Note: The brackets are required in the event that the DB name
 		// contains reserved characters
-		if (@mssql_select_db('['.$database.']', $this->conn_id))
+		if (@mssql_select_db($this->escape_identifiers($database), $this->conn_id))
 		{
 			$this->database = $database;
 			return TRUE;
@@ -121,7 +162,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 * Execute the query
 	 *
 	 * @param	string	an SQL query
-	 * @return	resource
+	 * @return	mixed	resource if rows are returned, bool otherwise
 	 */
 	protected function _execute($sql)
 	{
@@ -137,13 +178,8 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -151,10 +187,9 @@ class CI_DB_mssql_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('BEGIN TRAN');
-		return TRUE;
+		return $this->simple_query('BEGIN TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -166,19 +201,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	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;
 		}
 
-		$this->simple_query('COMMIT TRAN');
-		return TRUE;
+		return $this->simple_query('COMMIT TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -190,19 +219,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	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;
 		}
 
-		$this->simple_query('ROLLBACK TRAN');
-		return TRUE;
+		return $this->simple_query('ROLLBACK TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -232,7 +255,7 @@ class CI_DB_mssql_driver extends CI_DB {
 		// escape LIKE condition wildcards
 		if ($like === TRUE)
 		{
-			$str = str_replace(
+			return str_replace(
 				array($this->_like_escape_chr, '%', '_'),
 				array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
 				$str
@@ -265,11 +288,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function insert_id()
 	{
-		$ver = self::_parse_major_version($this->version());
-		$sql = ($ver >= 8 ? "SELECT SCOPE_IDENTITY() AS last_id" : "SELECT @@IDENTITY AS last_id");
-		$query = $this->query($sql);
-		$row = $query->row();
-		return $row->last_id;
+		$query = (self::_parse_major_version($this->version()) > 7)
+			? 'SELECT SCOPE_IDENTITY() AS last_id'
+			: 'SELECT @@IDENTITY AS last_id';
+
+		$query = $this->query($query);
+		$query = $query->row();
+		return $query->last_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -352,7 +377,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _field_data($table)
 	{
-		return "SELECT TOP 1 * FROM ".$table;
+		return 'SELECT TOP 1 * FROM '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -385,12 +410,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return implode(', ', $tables);
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
@@ -484,9 +504,30 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		$i = $limit + $offset;
+		// As of SQL Server 2012 (11.0.*) OFFSET is supported
+		if (version_compare($this->version(), '11', '>='))
+		{
+			return $sql.' OFFSET '.(int) $offset.' ROWS FETCH NEXT '.(int) $limit.' ROWS ONLY';
+		}
+
+		$limit = $offset + $limit;
+
+		// As of SQL Server 2005 (9.0.*) ROW_NUMBER() is supported,
+		// however an ORDER BY clause is required for it to work
+		if (version_compare($this->version(), '9', '>=') && $offset && ! empty($this->qb_orderby))
+		{
+			$orderby = 'ORDER BY '.implode(', ', $this->qb_orderby);
+
+			// We have to strip the ORDER BY clause
+			$sql = trim(substr($sql, 0, strrpos($sql, 'ORDER BY '.$orderby)));
+
+			return 'SELECT '.(count($this->qb_select) === 0 ? '*' : implode(', ', $this->qb_select))." FROM (\n"
+				.preg_replace('/^(SELECT( DISTINCT)?)/i', '\\1 ROW_NUMBER() OVER('.$orderby.') AS '.$this->escape_identifiers('CI_rownum').', ', $sql)
+				."\n) ".$this->escape_identifiers('CI_subquery')
+				."\nWHERE ".$this->escape_identifiers('CI_rownum').' BETWEEN '.((int) $offset + 1).' AND '.$limit;
+		}
 
-		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$i.' ', $sql);
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$limit.' ', $sql);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mssql/mssql_forge.php b/system/database/drivers/mssql/mssql_forge.php
index 3708c2233..3a3528f7b 100644
--- a/system/database/drivers/mssql/mssql_forge.php
+++ b/system/database/drivers/mssql/mssql_forge.php
@@ -70,31 +70,25 @@ class CI_DB_mssql_forge extends CI_DB_forge {
 
 				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				if (array_key_exists('CONSTRAINT', $attributes))
+				if (stripos($attributes['TYPE'], 'INT') === FALSE && ! empty($attributes['CONSTRAINT']))
 				{
 					$sql .= '('.$attributes['CONSTRAINT'].')';
 				}
 
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -109,22 +103,16 @@ class CI_DB_mssql_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
@@ -152,7 +140,7 @@ class CI_DB_mssql_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($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->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -160,21 +148,10 @@ class CI_DB_mssql_forge extends CI_DB_forge {
 			return $sql;
 		}
 
-		$sql .= " ".$column_definition;
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT '".$default_value."'";
-		}
-
-		$sql .= ($null === NULL) ? ' NULL' : ' NOT NULL';
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
+		return $sql.' '.$column_definition
+			.($default_value != '' ? ' DEFAULT "'.$default_value.'"' : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field != '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mssql/mssql_result.php b/system/database/drivers/mssql/mssql_result.php
index 4cc87f4cf..5929306af 100644
--- a/system/database/drivers/mssql/mssql_result.php
+++ b/system/database/drivers/mssql/mssql_result.php
@@ -92,12 +92,12 @@ class CI_DB_mssql_result extends CI_DB_result {
 		$retval = array();
 		while ($field = mssql_fetch_field($this->result_id))
 		{
-			$F				= new stdClass();
-			$F->name		= $field->name;
-			$F->type		= $field->type;
+			$F		= new stdClass();
+			$F->name	= $field->name;
+			$F->type	= $field->type;
 			$F->max_length	= $field->max_length;
 			$F->primary_key = 0;
-			$F->default		= '';
+			$F->default	= '';
 
 			$retval[] = $F;
 		}
diff --git a/system/database/drivers/mssql/mssql_utility.php b/system/database/drivers/mssql/mssql_utility.php
index 6d47618ce..69fcec5f6 100644
--- a/system/database/drivers/mssql/mssql_utility.php
+++ b/system/database/drivers/mssql/mssql_utility.php
@@ -41,7 +41,7 @@ class CI_DB_mssql_utility extends CI_DB_utility {
 	 * MSSQL Export
 	 *
 	 * @param	array	Preferences
-	 * @return	mixed
+	 * @return	bool
 	 */
 	protected function _backup($params = array())
 	{
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index 5937b223b..8938d22b5 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -412,27 +412,6 @@ class CI_DB_mysql_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	string	table name
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Update_Batch statement
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
diff --git a/system/database/drivers/mysql/mysql_forge.php b/system/database/drivers/mysql/mysql_forge.php
index ffd374fbf..d22454d84 100644
--- a/system/database/drivers/mysql/mysql_forge.php
+++ b/system/database/drivers/mysql/mysql_forge.php
@@ -60,8 +60,9 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR ' '.$this->db->escape_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
@@ -86,10 +87,23 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 					}
 				}
 
-				$sql .= (( ! empty($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']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -123,12 +137,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= $this->db->protect_identifiers($table).' ('.$this->_process_fields($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));
-			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers(implode('_', $primary_keys));
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -137,12 +151,12 @@ class CI_DB_mysql_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->escape_identifiers(implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers($key);
 					$key = array($key_name);
 				}
 
@@ -169,16 +183,16 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mysql/mysql_utility.php b/system/database/drivers/mysql/mysql_utility.php
index 643682fde..f0bbc665e 100644
--- a/system/database/drivers/mysql/mysql_utility.php
+++ b/system/database/drivers/mysql/mysql_utility.php
@@ -65,7 +65,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 			}
 
 			// Get the table schema
-			$query = $this->db->query('SHOW CREATE TABLE '.$this->db->protect_identifiers($this->db->database).'.'.$this->db->protect_identifiers($table));
+			$query = $this->db->query('SHOW CREATE TABLE '.$this->db->escape_identifiers($this->db->database.'.'.$table));
 
 			// No result means the table name was invalid
 			if ($query === FALSE)
@@ -120,7 +120,7 @@ class CI_DB_mysql_utility extends CI_DB_utility {
 							TRUE);
 
 				// Create a string of field names
-				$field_str .= $this->db->protect_identifiers($field->name).', ';
+				$field_str .= $this->db->escape_identifiers($field->name).', ';
 				$i++;
 			}
 
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index 02f893755..d3fb77a22 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -412,27 +412,6 @@ class CI_DB_mysqli_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	string
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Update_Batch statement
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
diff --git a/system/database/drivers/mysqli/mysqli_forge.php b/system/database/drivers/mysqli/mysqli_forge.php
index b00bfde49..b74c775b2 100644
--- a/system/database/drivers/mysqli/mysqli_forge.php
+++ b/system/database/drivers/mysqli/mysqli_forge.php
@@ -60,13 +60,13 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '')
-				;
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR $sql .= ' '.$this->db->escape_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
-					$sql .=  ' '.$attributes['TYPE'];
+					$sql .= ' '.$attributes['TYPE'];
 
 					if ( ! empty($attributes['CONSTRAINT']))
 					{
@@ -87,10 +87,23 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 					}
 				}
 
-				$sql .= (( ! empty($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']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -128,8 +141,8 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->protect_identifiers(implode('_', $primary_keys));
-			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers(implode('_', $primary_keys));
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -138,12 +151,12 @@ 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->escape_identifiers(implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers($key);
 					$key = array($key_name);
 				}
 
@@ -170,16 +183,16 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mysqli/mysqli_utility.php b/system/database/drivers/mysqli/mysqli_utility.php
index 27d4ef817..5d2bdbce0 100644
--- a/system/database/drivers/mysqli/mysqli_utility.php
+++ b/system/database/drivers/mysqli/mysqli_utility.php
@@ -46,9 +46,124 @@ class CI_DB_mysqli_utility extends CI_DB_utility {
 	 */
 	protected function _backup($params = array())
 	{
-		// Currently unsupported
-		return $this->db->display_error('db_unsuported_feature');
+		if (count($params) === 0)
+		{
+			return FALSE;
+		}
+
+		// Extract the prefs for simplicity
+		extract($params);
+
+		// Build the output
+		$output = '';
+		foreach ( (array) $tables as $table)
+		{
+			// Is the table in the "ignore" list?
+			if (in_array($table, (array) $ignore, TRUE))
+			{
+				continue;
+			}
+
+			// Get the table schema
+			$query = $this->db->query('SHOW CREATE TABLE '.$this->db->escape_identifiers($this->db->database.'.'.$table));
+
+			// No result means the table name was invalid
+			if ($query === FALSE)
+			{
+				continue;
+			}
+
+			// Write out the table schema
+			$output .= '#'.$newline.'# TABLE STRUCTURE FOR: '.$table.$newline.'#'.$newline.$newline;
+
+			if ($add_drop === TRUE)
+			{
+				$output .= 'DROP TABLE IF EXISTS '.$this->db->protect_identifiers($table).';'.$newline.$newline;
+			}
+
+			$i = 0;
+			$result = $query->result_array();
+			foreach ($result[0] as $val)
+			{
+				if ($i++ % 2)
+				{
+					$output .= $val.';'.$newline.$newline;
+				}
+			}
+
+			// If inserts are not needed we're done...
+			if ($add_insert === FALSE)
+			{
+				continue;
+			}
+
+			// Grab all the data from the current table
+			$query = $this->db->query('SELECT * FROM '.$this->db->protect_identifiers($table));
+
+			if ($query->num_rows() === 0)
+			{
+				continue;
+			}
+
+			// Fetch the field names and determine if the field is an
+			// integer type. We use this info to decide whether to
+			// surround the data with quotes or not
+
+			$i = 0;
+			$field_str = '';
+			$is_int = array();
+			while ($field = $query->result_id->fetch_field())
+			{
+				// Most versions of MySQL store timestamp as a string
+				$is_int[$i] = in_array(strtolower($field->type),
+							array('tinyint', 'smallint', 'mediumint', 'int', 'bigint'), //, 'timestamp'),
+							TRUE);
+
+				// Create a string of field names
+				$field_str .= $this->db->escape_identifiers($field->name).', ';
+				$i++;
+			}
+
+			// Trim off the end comma
+			$field_str = preg_replace('/, $/' , '', $field_str);
+
+			// Build the insert string
+			foreach ($query->result_array() as $row)
+			{
+				$val_str = '';
+
+				$i = 0;
+				foreach ($row as $v)
+				{
+					// Is the value NULL?
+					if ($v === NULL)
+					{
+						$val_str .= 'NULL';
+					}
+					else
+					{
+						// Escape the data if it's not an integer
+						$val_str .= ($is_int[$i] === FALSE) ? $this->db->escape($v) : $v;
+					}
+
+					// Append a comma
+					$val_str .= ', ';
+					$i++;
+				}
+
+				// Remove the comma at the end of the string
+				$val_str = preg_replace('/, $/' , '', $val_str);
+
+				// Build the INSERT string
+				$output .= 'INSERT INTO '.$this->db->protect_identifiers($table).' ('.$field_str.') VALUES ('.$val_str.');'.$newline;
+			}
+
+			$output .= $newline.$newline;
+		}
+
+		return $output;
 	}
+
 }
 
 /* End of file mysqli_utility.php */
diff --git a/system/database/drivers/oci8/oci8_forge.php b/system/database/drivers/oci8/oci8_forge.php
index 837e7eaad..92e8c02ed 100644
--- a/system/database/drivers/oci8/oci8_forge.php
+++ b/system/database/drivers/oci8/oci8_forge.php
@@ -73,11 +73,22 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field).' '.$attributes['TYPE']
-					.((isset($attributes['UNSINGED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
-					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.((isset($attributes['NULL']) && $attributes['NULL'] === TRUE) ? '' : ' NOT NULL')
-					.(isset($attributes['CONSTRAINT']) ? ' CONSTRAINT '.$attributes['CONSTRAINT'] : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
+
+				if (isset($attributes['UNSINGED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= (isset($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? '' : ' NOT NULL';
+
+				empty($attributes['CONSTRAINT']) OR ' CONSTRAINT '.$attributes['CONSTRAINT'];
 			}
 
 			// don't add a comma on the end of the last field
@@ -89,22 +100,16 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tCONSTRAINT ".$table.' PRIMARY KEY ('.implode(', ', $primary_keys).')';
+			$sql .= ",\n\tCONSTRAINT ".$table.' PRIMARY KEY ('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				$sql .= ",\n\tUNIQUE COLUMNS (".implode(', ', $key).')';
 			}
@@ -132,7 +137,7 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($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->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -143,7 +148,7 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 		return $sql.' '.$column_definition
 			.($default_value !== '' ? ' DEFAULT "'.$default_value.'"' : '')
 			.($null === NULL ? ' NULL' : ' NOT NULL')
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 
 	}
 
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index c3735da05..222c311c0 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -114,13 +114,8 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -128,7 +123,7 @@ class CI_DB_odbc_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);
 
 		return odbc_autocommit($this->conn_id, FALSE);
 	}
@@ -142,13 +137,8 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -167,13 +157,8 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -204,7 +189,6 @@ class CI_DB_odbc_driver extends CI_DB {
 			return $str;
 		}
 
-		// ODBC doesn't require escaping
 		$str = remove_invisible_characters($str);
 
 		// escape LIKE condition wildcards
@@ -277,7 +261,7 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	protected function _list_columns($table = '')
 	{
-		return "SHOW COLUMNS FROM ".$table;
+		return 'SHOW COLUMNS FROM '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -292,7 +276,7 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	protected function _field_data($table)
 	{
-		return "SELECT TOP 1 FROM ".$table;
+		return 'SELECT TOP 1 FROM '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -323,12 +307,7 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
@@ -363,8 +342,7 @@ class CI_DB_odbc_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		// Does ODBC doesn't use the LIMIT clause?
-		return $sql;
+		return $sql.($offset == 0 ? '' : $offset.', ').$limit;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/odbc/odbc_forge.php b/system/database/drivers/odbc/odbc_forge.php
index ce7a1d2ef..b074c5884 100644
--- a/system/database/drivers/odbc/odbc_forge.php
+++ b/system/database/drivers/odbc/odbc_forge.php
@@ -66,41 +66,30 @@ class CI_DB_odbc_forge extends CI_DB_forge {
 			// 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);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
 
-				if (array_key_exists('CONSTRAINT', $attributes))
-				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
-				}
-
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -115,30 +104,22 @@ class CI_DB_odbc_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tFOREIGN KEY (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -160,7 +141,7 @@ class CI_DB_odbc_forge extends CI_DB_forge {
 	 */
 	protected 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->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -168,29 +149,10 @@ class CI_DB_odbc_forge extends CI_DB_forge {
 			return $sql;
 		}
 
-		$sql .= " $column_definition";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return $sql.' '.$column_definition
+			.($default_value != '' ? ' DEFAULT "'.$default_value.'"' : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field != '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/odbc/odbc_result.php b/system/database/drivers/odbc/odbc_result.php
index ecba5977e..227fe4fac 100644
--- a/system/database/drivers/odbc/odbc_result.php
+++ b/system/database/drivers/odbc/odbc_result.php
@@ -59,8 +59,6 @@ class CI_DB_odbc_result extends CI_DB_result {
 		return $this->num_rows;
 	}
 
-	// --------------------------------------------------------------------
-
 	/**
 	 * Number of fields in the result set
 	 *
@@ -148,14 +146,9 @@ class CI_DB_odbc_result extends CI_DB_result {
 	 */
 	protected function _fetch_assoc()
 	{
-		if (function_exists('odbc_fetch_array'))
-		{
-			return odbc_fetch_array($this->result_id);
-		}
-		else
-		{
-			return $this->_odbc_fetch_array($this->result_id);
-		}
+		return function_exists('odbc_fetch_array')
+			? odbc_fetch_array($this->result_id)
+			: $this->_odbc_fetch_array($this->result_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -169,14 +162,9 @@ class CI_DB_odbc_result extends CI_DB_result {
 	 */
 	protected function _fetch_object()
 	{
-		if (function_exists('odbc_fetch_object'))
-		{
-			return odbc_fetch_object($this->result_id);
-		}
-		else
-		{
-			return $this->_odbc_fetch_object($this->result_id);
-		}
+		return function_exists('odbc_fetch_object')
+			? odbc_fetch_object($this->result_id)
+			: $this->_odbc_fetch_object($this->result_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -192,15 +180,18 @@ class CI_DB_odbc_result extends CI_DB_result {
 	protected function _odbc_fetch_object(& $odbc_result)
 	{
 		$rs = array();
-		$rs_obj = FALSE;
-		if (odbc_fetch_into($odbc_result, $rs))
+		if ( ! odbc_fetch_into($odbc_result, $rs))
 		{
-			foreach ($rs as $k => $v)
-			{
-				$field_name = odbc_field_name($odbc_result, $k+1);
-				$rs_obj->$field_name = $v;
-			}
+			return FALSE;
+		}
+
+		$rs_obj = new stdClass();
+		foreach ($rs as $k => $v)
+		{
+			$field_name = odbc_field_name($odbc_result, $k+1);
+			$rs_obj->$field_name = $v;
 		}
+
 		return $rs_obj;
 	}
 
@@ -217,16 +208,18 @@ class CI_DB_odbc_result extends CI_DB_result {
 	protected function _odbc_fetch_array(& $odbc_result)
 	{
 		$rs = array();
-		$rs_assoc = FALSE;
-		if (odbc_fetch_into($odbc_result, $rs))
+		if ( ! odbc_fetch_into($odbc_result, $rs))
 		{
-			$rs_assoc = array();
-			foreach ($rs as $k => $v)
-			{
-				$field_name = odbc_field_name($odbc_result, $k+1);
-				$rs_assoc[$field_name] = $v;
-			}
+			return FALSE;
+		}
+
+		$rs_assoc = array();
+		foreach ($rs as $k => $v)
+		{
+			$field_name = odbc_field_name($odbc_result, $k+1);
+			$rs_assoc[$field_name] = $v;
 		}
+
 		return $rs_assoc;
 	}
 
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index b4ad52a45..e25013a52 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -519,27 +519,6 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	array
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return (count($tables) === 1) ? $tables[0] : '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Update_Batch statement
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
diff --git a/system/database/drivers/pdo/pdo_forge.php b/system/database/drivers/pdo/pdo_forge.php
index aee8f718a..02ceb74fe 100644
--- a/system/database/drivers/pdo/pdo_forge.php
+++ b/system/database/drivers/pdo/pdo_forge.php
@@ -66,18 +66,16 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			// entered the field information, so we'll simply add it to the list
 			if (is_numeric($field))
 			{
-				$sql .= "\n\t$attributes";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
-				$numeric    = array('SERIAL', 'INTEGER');
+				$numeric = array('SERIAL', 'INTEGER');
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
-
-				if (array_key_exists('CONSTRAINT', $attributes))
+				if ( ! empty($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)))
@@ -86,26 +84,20 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 					}
 				}
 
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -120,30 +112,22 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tFOREIGN KEY (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -165,7 +149,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 	 */
 	protected 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->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -173,29 +157,10 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			return $sql;
 		}
 
-		$sql .= " $column_definition";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return $sql .' '.$column_definition
+			.($default_value !== '' ? " DEFAULT '".$default_value."'" : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index e5d861bd9..ad9ac9000 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -467,12 +467,7 @@ class CI_DB_postgre_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return implode(', ', $tables);
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
@@ -620,6 +615,10 @@ class CI_DB_postgre_driver extends CI_DB {
 		{
 			$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0) ? '' : $type;
 
+			$k = $this->_has_operator($k)
+				? $this->protect_identifiers(substr($k, 0, strpos(rtrim($k), ' ')), FALSE, $escape).strchr(rtrim($k), ' ')
+				: $this->protect_identifiers($k, FALSE, $escape);
+
 			if (is_null($v) && ! $this->_has_operator($k))
 			{
 				// value appears not to have been set, assign the test to IS NULL
@@ -630,7 +629,6 @@ class CI_DB_postgre_driver extends CI_DB {
 			{
 				if ($escape === TRUE)
 				{
-					$k = $this->protect_identifiers($k, FALSE, $escape);
 					$v = ' '.$this->escape($v);
 				}
 				elseif (is_bool($v))
@@ -643,10 +641,6 @@ class CI_DB_postgre_driver extends CI_DB {
 					$k .= ' = ';
 				}
 			}
-			else
-			{
-				$k = $this->protect_identifiers($k, FALSE, $escape);
-			}
 
 			$this->qb_where[] = $prefix.$k.$v;
 			if ($this->qb_caching === TRUE)
diff --git a/system/database/drivers/postgre/postgre_forge.php b/system/database/drivers/postgre/postgre_forge.php
index af1c45f9b..c434e9510 100644
--- a/system/database/drivers/postgre/postgre_forge.php
+++ b/system/database/drivers/postgre/postgre_forge.php
@@ -58,7 +58,7 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 			}
 			else
 			{
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
 
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 				$is_unsigned = ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE);
@@ -107,10 +107,19 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 					$sql .= '('.$attributes['CONSTRAINT'].')';
 				}
 
-				$sql .= (isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					// Added new attribute to create unqite fields. Also works with MySQL
-					.(( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE) ? ' UNIQUE' : '');
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				// Added new attribute to create unique fields. Also works with MySQL
+				if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+				{
+					$sql .= ' UNIQUE';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -139,26 +148,17 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 	{
 		$sql = 'CREATE TABLE ';
 
-		if ($if_not_exists === TRUE)
+		// PostgreSQL doesn't support IF NOT EXISTS syntax so we check if table exists manually
+		if ($if_not_exists === TRUE && $this->db->table_exists($table))
 		{
-			// PostgreSQL doesn't support IF NOT EXISTS syntax so we check if table exists manually
-			if ($this->db->table_exists($table))
-			{
-				return TRUE;
-			}
+			return TRUE;
 		}
 
 		$sql .= $this->db->escape_identifiers($table).' ('.$this->_process_fields($fields, $primary_keys);
 
 		if (count($primary_keys) > 0)
 		{
-			// Something seems to break when passing an array to protect_identifiers()
-			foreach ($primary_keys as $index => $key)
-			{
-				$primary_keys[$index] = $this->db->protect_identifiers($key);
-			}
-
-			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		$sql .= "\n);";
@@ -167,18 +167,14 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				foreach ($key as $field)
 				{
-					$sql .= 'CREATE INDEX '.$table.'_'.str_replace(array('"', "'"), '', $field).'_index ON '.$table.' ('.$field.'); ';
+					$sql .= "\nCREATE INDEX ".$this->db->escape_identifiers($table.'_'.str_replace(array('"', "'"), '', $field).'_index')
+						.' ON '.$this->db->escape_identifiers($table).' ('.$this->db->escape_identifiers($field).');';
 				}
 			}
 		}
@@ -205,16 +201,16 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
  	{
- 		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+ 		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
  		// DROP has everything it needs now.
  		if ($alter_type === 'DROP')
  		{
- 			return $sql.$this->db->protect_identifiers($fields);
+ 			return $sql.$this->db->escape_identifiers($fields);
  		}
 
  		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
  	}
 
 }
diff --git a/system/database/drivers/sqlite/sqlite_driver.php b/system/database/drivers/sqlite/sqlite_driver.php
index f52b1ba1b..3305f6030 100644
--- a/system/database/drivers/sqlite/sqlite_driver.php
+++ b/system/database/drivers/sqlite/sqlite_driver.php
@@ -43,7 +43,7 @@ class CI_DB_sqlite_driver extends CI_DB {
 	public $dbdriver = 'sqlite';
 
 	// The character used to escape with - not needed for SQLite
-	protected $_escape_char = '';
+	protected $_escape_char = '"';
 
 	// clause and character used for LIKE escape sequences
 	protected $_like_escape_str = " ESCAPE '%s' ";
@@ -127,7 +127,9 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	protected function _execute($sql)
 	{
-		return @sqlite_query($this->conn_id, $sql);
+		return $this->is_write_type($sql)
+			? @sqlite_exec($this->conn_id, $sql)
+			: @sqlite_query($this->conn_id, $sql);
 	}
 
 	// --------------------------------------------------------------------
@@ -139,13 +141,8 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -153,7 +150,7 @@ class CI_DB_sqlite_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('BEGIN TRANSACTION');
 		return TRUE;
@@ -168,13 +165,8 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -192,13 +184,8 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	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 $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -277,12 +264,13 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SELECT name from sqlite_master WHERE type='table'";
+		$sql = "SELECT name FROM sqlite_master WHERE type='table'";
 
 		if ($prefix_limit !== FALSE && $this->dbprefix != '')
 		{
-			$sql .= " AND 'name' LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
+			return $sql." AND 'name' LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
 		}
+
 		return $sql;
 	}
 
@@ -314,7 +302,7 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	protected function _field_data($table)
 	{
-		return "SELECT * FROM ".$table." LIMIT 1";
+		return 'SELECT * FROM '.$this->escape_identifiers($table).' LIMIT 1';
 	}
 
 	// --------------------------------------------------------------------
@@ -337,27 +325,6 @@ class CI_DB_sqlite_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	array
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Replace statement
 	 *
 	 * Generates a platform-specific replace string from the supplied data
@@ -404,16 +371,7 @@ class CI_DB_sqlite_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		if ($offset == 0)
-		{
-			$offset = '';
-		}
-		else
-		{
-			$offset .= ', ';
-		}
-
-		return $sql.'LIMIT '.$offset.$limit;
+		return $sql.'LIMIT '.($offset == 0 ? '' : $offset.', ').$limit;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/sqlite/sqlite_forge.php b/system/database/drivers/sqlite/sqlite_forge.php
index 35be1b74b..e02e327f3 100644
--- a/system/database/drivers/sqlite/sqlite_forge.php
+++ b/system/database/drivers/sqlite/sqlite_forge.php
@@ -61,6 +61,14 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 		{
 			return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
 		}
+		elseif ( ! empty($this->db->data_cache['db_names']))
+		{
+			$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+			if ($key !== FALSE)
+			{
+				unset($this->db->data_cache['db_names'][$key]);
+			}
+		}
 
 		return TRUE;
 	}
@@ -97,41 +105,31 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 			// 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);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
 
-				if (array_key_exists('CONSTRAINT', $attributes))
-				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
-				}
-
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$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)
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -146,30 +144,22 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tUNIQUE (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tUNIQUE (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -191,40 +181,21 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' '.$this->db->protect_identifiers($column_name);
-
-		// DROP has everything it needs now.
-		if ($alter_type === 'DROP')
+		/* SQLite only supports adding new columns and it does
+		 * NOT support the AFTER statement. Each new column will
+		 * be added as the last one in the table.
+		 */
+		if ($alter_type !== 'ADD COLUMN')
 		{
-			// SQLite does not support dropping columns
-			// http://www.sqlite.org/omitted.html
-			// http://www.sqlite.org/faq.html#q11
+			// Not supported
 			return FALSE;
 		}
 
-		$sql .= " $column_definition";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
+			.' '.$column_definition
+			.($default_value != '' ? " DEFAULT '".$default_value."'" : '')
+			// If NOT NULL is specified, the field must have a DEFAULT value other than NULL
+			.(($null !== NULL && $default_value !== 'NULL') ? ' NOT NULL' : ' NULL');
 	}
 
 }
diff --git a/system/database/drivers/sqlite3/sqlite3_driver.php b/system/database/drivers/sqlite3/sqlite3_driver.php
index 2acefbcf4..bed61891b 100644
--- a/system/database/drivers/sqlite3/sqlite3_driver.php
+++ b/system/database/drivers/sqlite3/sqlite3_driver.php
@@ -318,27 +318,6 @@ class CI_DB_sqlite3_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	string
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Replace statement
 	 *
 	 * Generates a platform-specific replace string from the supplied data
diff --git a/system/database/drivers/sqlite3/sqlite3_forge.php b/system/database/drivers/sqlite3/sqlite3_forge.php
index 0a5dc9211..6a76ba929 100644
--- a/system/database/drivers/sqlite3/sqlite3_forge.php
+++ b/system/database/drivers/sqlite3/sqlite3_forge.php
@@ -66,6 +66,14 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 			{
 				return $this->db->db_debug ? $this->db->display_error('db_unable_to_drop') : FALSE;
 			}
+			elseif ( ! empty($this->db->data_cache['db_names']))
+			{
+				$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
+				if ($key !== FALSE)
+				{
+					unset($this->db->data_cache['db_names'][$key]);
+				}
+			}
 
 			return TRUE;
 		}
@@ -111,13 +119,27 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.' '.$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' : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
+
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
+
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -129,22 +151,16 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				$sql .= ",\n\tUNIQUE (".implode(', ', $key).')';
 			}
@@ -182,7 +198,7 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 			return FALSE;
 		}
 
-		return 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' '.$this->db->protect_identifiers($column_name)
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
 			.' '.$column_definition
 			.($default_value !== '' ? ' DEFAULT '.$default_value : '')
 			// If NOT NULL is specified, the field must have a DEFAULT value other than NULL
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index 961066da7..825c02452 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -21,7 +21,7 @@
  * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
  * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
  * @link		http://codeigniter.com
- * @since		Version 1.0
+ * @since		Version 2.0.3
  * @filesource
  */
 
@@ -43,7 +43,7 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	public $dbdriver = 'sqlsrv';
 
 	// The character used for escaping
-	protected $_escape_char = '';
+	protected $_escape_char = '"';
 
 	// clause and character used for LIKE escape sequences
 	protected $_like_escape_str = " ESCAPE '%s' ";
@@ -55,7 +55,10 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * used for the count_all() and count_all_results() functions.
 	 */
 	protected $_count_string = 'SELECT COUNT(*) AS ';
-	protected $_random_keyword = ' NEWID()'; // not currently supported
+	protected $_random_keyword = ' NEWID()';
+
+	// SQLSRV-specific properties
+	protected $_quoted_identifier = TRUE;
 
 	/**
 	 * Non-persistent database connection
@@ -83,7 +86,15 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 			unset($connection['UID'], $connection['PWD']);
 		}
 
-		return sqlsrv_connect($this->hostname, $connection);
+		$conn_id = sqlsrv_connect($this->hostname, $connection);
+
+		// Determine how identifiers are escaped
+		$query = $this->query('SELECT CASE WHEN (@@OPTIONS | 256) = @@OPTIONS THEN 1 ELSE 0 END AS qi');
+		$query = $query->row_array();
+		$this->_quoted_identifier = empty($query) ? FALSE : (bool) $query->qi;
+		$this->_escape_char = ($this->_quoted_identifier) ? '"' : array('[', ']');
+
+		return $conn_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -146,13 +157,8 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -160,7 +166,7 @@ class CI_DB_sqlsrv_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);
 
 		return sqlsrv_begin_transaction($this->conn_id);
 	}
@@ -174,13 +180,8 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	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;
 		}
@@ -197,13 +198,8 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	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 $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -372,12 +368,7 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return implode(', ', $tables);
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
@@ -397,7 +388,7 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
 	{
-		foreach($values as $key => $val)
+		foreach ($values as $key => $val)
 		{
 			$valstr[] = $key.' = '.$val;
 		}
@@ -471,7 +462,29 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.($limit + $offset).' ', $sql);
+		// As of SQL Server 2012 (11.0.*) OFFSET is supported
+		if (version_compare($this->version(), '11', '>='))
+		{
+			return $sql.' OFFSET '.(int) $offset.' ROWS FETCH NEXT '.(int) $limit.' ROWS ONLY';
+		}
+
+		$limit = $offset + $limit;
+
+		// An ORDER BY clause is required for ROW_NUMBER() to work
+		if ($offset && ! empty($this->qb_orderby))
+		{
+			$orderby = 'ORDER BY '.implode(', ', $this->qb_orderby);
+
+			// We have to strip the ORDER BY clause
+			$sql = trim(substr($sql, 0, strrpos($sql, 'ORDER BY '.$orderby)));
+
+			return 'SELECT '.(count($this->qb_select) === 0 ? '*' : implode(', ', $this->qb_select))." FROM (\n"
+				.preg_replace('/^(SELECT( DISTINCT)?)/i', '\\1 ROW_NUMBER() OVER('.$orderby.') AS '.$this->escape_identifiers('CI_rownum').', ', $sql)
+				."\n) ".$this->escape_identifiers('CI_subquery')
+				."\nWHERE ".$this->escape_identifiers('CI_rownum').' BETWEEN '.((int) $offset + 1).' AND '.$limit;
+		}
+
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$limit.' ', $sql);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/sqlsrv/sqlsrv_forge.php b/system/database/drivers/sqlsrv/sqlsrv_forge.php
index 1529b2a21..ccdb36929 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_forge.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_forge.php
@@ -21,7 +21,7 @@
  * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
  * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
  * @link		http://codeigniter.com
- * @since		Version 1.0
+ * @since		Version 2.0.3
  * @filesource
  */
 
@@ -44,7 +44,7 @@ class CI_DB_sqlsrv_forge extends CI_DB_forge {
 	 * @param	mixed	primary key(s)
 	 * @param	mixed	key(s)
 	 * @param	bool	should 'IF NOT EXISTS' be added to the SQL
-	 * @return	bool
+	 * @return	string
 	 */
 	protected function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
 	{
@@ -70,31 +70,25 @@ class CI_DB_sqlsrv_forge extends CI_DB_forge {
 
 				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				if (array_key_exists('CONSTRAINT', $attributes))
+				if (stripos($attributes['TYPE'], 'INT') === FALSE && ! empty($attributes['CONSTRAINT']))
 				{
 					$sql .= '('.$attributes['CONSTRAINT'].')';
 				}
 
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attribues['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -109,22 +103,16 @@ class CI_DB_sqlsrv_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->escape_identifiers($key));
 
 				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
@@ -152,7 +140,7 @@ class CI_DB_sqlsrv_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($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->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -160,21 +148,10 @@ class CI_DB_sqlsrv_forge extends CI_DB_forge {
 			return $sql;
 		}
 
-		$sql .= ' '.$column_definition;
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT '".$default_value."'";
-		}
-
-		$sql .= ($null === NULL) ? ' NULL' : ' NOT NULL';
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
+		return $sql.' '.$column_definition
+			.($default_value != '' ? ' DEFAULT "'.$default_value.'"' : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field != '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/sqlsrv/sqlsrv_result.php b/system/database/drivers/sqlsrv/sqlsrv_result.php
index 0802677fc..f9d5a0d29 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_result.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_result.php
@@ -21,7 +21,7 @@
  * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
  * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
  * @link		http://codeigniter.com
- * @since		Version 1.0
+ * @since		Version 2.0.3
  * @filesource
  */
 
@@ -92,12 +92,12 @@ class CI_DB_sqlsrv_result extends CI_DB_result {
 		$retval = array();
 		foreach (sqlsrv_field_metadata($this->result_id) as $offset => $field)
 		{
-			$F 				= new stdClass();
-			$F->name 		= $field['Name'];
-			$F->type 		= $field['Type'];
+			$F 		= new stdClass();
+			$F->name 	= $field['Name'];
+			$F->type 	= $field['Type'];
 			$F->max_length	= $field['Size'];
 			$F->primary_key = 0;
-			$F->default		= '';
+			$F->default	= '';
 
 			$retval[] = $F;
 		}
diff --git a/system/database/drivers/sqlsrv/sqlsrv_utility.php b/system/database/drivers/sqlsrv/sqlsrv_utility.php
index 394964b6a..d518cc15a 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_utility.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_utility.php
@@ -21,7 +21,7 @@
  * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
  * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
  * @link		http://codeigniter.com
- * @since		Version 1.0
+ * @since		Version 2.0.3
  * @filesource
  */
 
@@ -41,7 +41,7 @@ class CI_DB_sqlsrv_utility extends CI_DB_utility {
 	 * SQLSRV Export
 	 *
 	 * @param	array	Preferences
-	 * @return	mixed
+	 * @return	bool
 	 */
 	protected function _backup($params = array())
 	{
diff --git a/system/helpers/date_helper.php b/system/helpers/date_helper.php
index c601dc9e5..077a6712c 100644
--- a/system/helpers/date_helper.php
+++ b/system/helpers/date_helper.php
@@ -42,29 +42,28 @@ if ( ! function_exists('now'))
 	/**
 	 * Get "now" time
 	 *
-	 * Returns time() or its GMT equivalent based on the config file preference
+	 * Returns time() based on the timezone parameter or on the
+	 * "time_reference" setting
 	 *
+	 * @param	string
 	 * @return	int
 	 */
-	function now()
+	function now($timezone = NULL)
 	{
-		$CI =& get_instance();
-
-		if (strtolower($CI->config->item('time_reference')) === 'gmt')
+		if (empty($timezone))
 		{
-			$now = time();
-			$system_time = mktime(gmdate("H", $now), gmdate("i", $now), gmdate("s", $now), gmdate("m", $now), gmdate("d", $now), gmdate("Y", $now));
-
-			if (strlen($system_time) < 10)
-			{
-				$system_time = time();
-				log_message('error', 'The Date class could not set a proper GMT timestamp so the local time() value was used.');
-			}
+			$timezone = config_item('time_reference');
+		}
 
-			return $system_time;
+		if ($timezone === 'local' OR $timezone === date_default_timezone_get())
+		{
+			return time();
 		}
 
-		return time();
+		$datetime = new DateTime('now', new DateTimeZone($timezone));
+		sscanf($datetime->format('j-n-Y G:i:s'), '%d-%d-%d %d:%d:%d', $day, $month, $year, $hour, $minute, $second);
+
+		return mktime($hour, $minute, $second, $month, $day, $year);
 	}
 }
 
@@ -94,8 +93,10 @@ if ( ! function_exists('mdate'))
 		{
 			return '';
 		}
-
-		$time = ($time === '') ? now() : $time;
+		elseif (empty($time))
+		{
+			$time = now();
+		}
 
 		$datestr = str_replace(
 			'%\\',
@@ -123,24 +124,19 @@ if ( ! function_exists('standard_date'))
 	function standard_date($fmt = 'DATE_RFC822', $time = '')
 	{
 		$formats = array(
-						'DATE_ATOM'		=>	'%Y-%m-%dT%H:%i:%s%O',
-						'DATE_COOKIE'	=>	'%l, %d-%M-%y %H:%i:%s UTC',
-						'DATE_ISO8601'	=>	'%Y-%m-%dT%H:%i:%s%O',
-						'DATE_RFC822'	=>	'%D, %d %M %y %H:%i:%s %O',
-						'DATE_RFC850'	=>	'%l, %d-%M-%y %H:%i:%s UTC',
-						'DATE_RFC1036'	=>	'%D, %d %M %y %H:%i:%s %O',
-						'DATE_RFC1123'	=>	'%D, %d %M %Y %H:%i:%s %O',
-						'DATE_RFC2822'	=>	'%D, %d %M %Y %H:%i:%s %O',
-						'DATE_RSS'		=>	'%D, %d %M %Y %H:%i:%s %O',
-						'DATE_W3C'		=>	'%Y-%m-%dT%H:%i:%s%O'
-						);
-
-		if ( ! isset($formats[$fmt]))
-		{
-			return FALSE;
-		}
-
-		return mdate($formats[$fmt], $time);
+				'DATE_ATOM'		=>	'%Y-%m-%dT%H:%i:%s%O',
+				'DATE_COOKIE'	=>	'%l, %d-%M-%y %H:%i:%s UTC',
+				'DATE_ISO8601'	=>	'%Y-%m-%dT%H:%i:%s%O',
+				'DATE_RFC822'	=>	'%D, %d %M %y %H:%i:%s %O',
+				'DATE_RFC850'	=>	'%l, %d-%M-%y %H:%i:%s UTC',
+				'DATE_RFC1036'	=>	'%D, %d %M %y %H:%i:%s %O',
+				'DATE_RFC1123'	=>	'%D, %d %M %Y %H:%i:%s %O',
+				'DATE_RFC2822'	=>	'%D, %d %M %Y %H:%i:%s %O',
+				'DATE_RSS'		=>	'%D, %d %M %Y %H:%i:%s %O',
+				'DATE_W3C'		=>	'%Y-%m-%dT%H:%i:%s%O'
+				);
+
+		return isset($formats[$fmt]) ? mdate($formats[$fmt], $time) : FALSE;
 	}
 }
 
@@ -164,20 +160,9 @@ if ( ! function_exists('timespan'))
 		$CI =& get_instance();
 		$CI->lang->load('date');
 
-		if ( ! is_numeric($seconds))
-		{
-			$seconds = 1;
-		}
-
-		if ( ! is_numeric($time))
-		{
-			$time = time();
-		}
-
-		if ( ! is_numeric($units))
-		{
-			$units = 7;
-		}
+		is_numeric($seconds) OR $seconds = 1;
+		is_numeric($time) OR $time = time();
+		is_numeric($units) OR $units = 7;
 
 		$seconds = ($time <= $seconds) ? 1 : $time - $seconds;
 
@@ -186,7 +171,7 @@ if ( ! function_exists('timespan'))
 
 		if ($years > 0)
 		{
-			$str[] = $years.' '.$CI->lang->line((($years	> 1) ? 'date_years' : 'date_year'));
+			$str[] = $years.' '.$CI->lang->line($years > 1 ? 'date_years' : 'date_year');
 		}
 
 		$seconds -= $years * 31557600;
@@ -196,7 +181,7 @@ if ( ! function_exists('timespan'))
 		{
 			if ($months > 0)
 			{
-				$str[] = $months.' '.$CI->lang->line((($months	> 1) ? 'date_months' : 'date_month'));
+				$str[] = $months.' '.$CI->lang->line($months > 1 ? 'date_months' : 'date_month');
 			}
 
 			$seconds -= $months * 2629743;
@@ -208,7 +193,7 @@ if ( ! function_exists('timespan'))
 		{
 			if ($weeks > 0)
 			{
-				$str[] = $weeks.' '.$CI->lang->line((($weeks	> 1) ? 'date_weeks' : 'date_week'));
+				$str[] = $weeks.' '.$CI->lang->line($weeks > 1 ? 'date_weeks' : 'date_week');
 			}
 
 			$seconds -= $weeks * 604800;
@@ -220,7 +205,7 @@ if ( ! function_exists('timespan'))
 		{
 			if ($days > 0)
 			{
-				$str[] = $days.' '.$CI->lang->line((($days	> 1) ? 'date_days' : 'date_day'));
+				$str[] = $days.' '.$CI->lang->line($days > 1 ? 'date_days' : 'date_day');
 			}
 
 			$seconds -= $days * 86400;
@@ -232,7 +217,7 @@ if ( ! function_exists('timespan'))
 		{
 			if ($hours > 0)
 			{
-				$str[] = $hours.' '.$CI->lang->line((($hours	> 1) ? 'date_hours' : 'date_hour'));
+				$str[] = $hours.' '.$CI->lang->line($hours > 1 ? 'date_hours' : 'date_hour');
 			}
 
 			$seconds -= $hours * 3600;
@@ -244,7 +229,7 @@ if ( ! function_exists('timespan'))
 		{
 			if ($minutes > 0)
 			{
-				$str[] = $minutes.' '.$CI->lang->line((($minutes	> 1) ? 'date_minutes' : 'date_minute'));
+				$str[] = $minutes.' '.$CI->lang->line($minutes > 1 ? 'date_minutes' : 'date_minute');
 			}
 
 			$seconds -= $minutes * 60;
@@ -252,7 +237,7 @@ if ( ! function_exists('timespan'))
 
 		if (count($str) === 0)
 		{
-			$str[] = $seconds.' '.$CI->lang->line((($seconds	> 1) ? 'date_seconds' : 'date_second'));
+			$str[] = $seconds.' '.$CI->lang->line($seconds > 1 ? 'date_seconds' : 'date_second');
 		}
 
 		return implode(', ', $str);
@@ -279,12 +264,16 @@ if ( ! function_exists('days_in_month'))
 		{
 			return 0;
 		}
-
-		if ( ! is_numeric($year) OR strlen($year) !== 4)
+		elseif ( ! is_numeric($year) OR strlen($year) !== 4)
 		{
 			$year = date('Y');
 		}
 
+		if ($year >= 1970)
+		{
+			return (int) date('t', mktime(12, 0, 0, $month, 1, $year));
+		}
+
 		if ($month == 2)
 		{
 			if ($year % 400 === 0 OR ($year % 4 === 0 && $year % 100 !== 0))
@@ -315,13 +304,13 @@ if ( ! function_exists('local_to_gmt'))
 			$time = time();
 		}
 
-		return mktime(
-			gmdate('H', $time),
-			gmdate('i', $time),
-			gmdate('s', $time),
-			gmdate('m', $time),
-			gmdate('d', $time),
-			gmdate('Y', $time)
+		return gmmktime(
+			date('G', $time),
+			date('i', $time),
+			date('s', $time),
+			date('n', $time),
+			date('j', $time),
+			date('Y', $time)
 		);
 	}
 }
@@ -351,12 +340,7 @@ if ( ! function_exists('gmt_to_local'))
 
 		$time += timezones($timezone) * 3600;
 
-		if ($dst === TRUE)
-		{
-			$time += 3600;
-		}
-
-		return $time;
+		return ($dst === TRUE) ? $time + 3600 : $time;
 	}
 }
 
@@ -376,9 +360,7 @@ if ( ! function_exists('mysql_to_unix'))
 		// since the formatting changed with MySQL 4.1
 		// YYYY-MM-DD HH:MM:SS
 
-		$time = str_replace('-', '', $time);
-		$time = str_replace(':', '', $time);
-		$time = str_replace(' ', '', $time);
+		$time = str_replace(array('-', ':', ' '), '', $time);
 
 		// YYYYMMDDHHMMSS
 		return mktime(
@@ -408,7 +390,7 @@ if ( ! function_exists('unix_to_human'))
 	 */
 	function unix_to_human($time = '', $seconds = FALSE, $fmt = 'us')
 	{
-		$r  = date('Y', $time).'-'.date('m', $time).'-'.date('d', $time).' ';
+		$r = date('Y', $time).'-'.date('m', $time).'-'.date('d', $time).' ';
 
 		if ($fmt === 'us')
 		{
@@ -426,7 +408,7 @@ if ( ! function_exists('unix_to_human'))
 
 		if ($fmt === 'us')
 		{
-			$r .= ' '.date('A', $time);
+			return $r.' '.date('A', $time);
 		}
 
 		return $r;
@@ -454,51 +436,33 @@ if ( ! function_exists('human_to_unix'))
 
 		$datestr = preg_replace('/\040+/', ' ', trim($datestr));
 
-		if ( ! preg_match('/^[0-9]{2,4}\-[0-9]{1,2}\-[0-9]{1,2}\s[0-9]{1,2}:[0-9]{1,2}(?::[0-9]{1,2})?(?:\s[AP]M)?$/i', $datestr))
+		if ( ! preg_match('/^(\d{2}|\d{4})\-[0-9]{1,2}\-[0-9]{1,2}\s[0-9]{1,2}:[0-9]{1,2}(?::[0-9]{1,2})?(?:\s[AP]M)?$/i', $datestr))
 		{
 			return FALSE;
 		}
 
 		$split = explode(' ', $datestr);
 
-		$ex = explode('-', $split['0']);
-
-		$year  = (strlen($ex[0]) === 2) ? '20'.$ex[0] : $ex[0];
-		$month = (strlen($ex[1]) === 1) ? '0'.$ex[1]  : $ex[1];
-		$day   = (strlen($ex[2]) === 1) ? '0'.$ex[2]  : $ex[2];
+		list($year, $month, $day) = explode('-', $split[0]);
 
 		$ex = explode(':', $split['1']);
 
-		$hour = (strlen($ex[0]) === 1) ? '0'.$ex[0] : $ex[0];
-		$min  = (strlen($ex[1]) === 1) ? '0'.$ex[1] : $ex[1];
-
-		if (isset($ex[2]) && preg_match('/[0-9]{1,2}/', $ex[2]))
-		{
-			$sec = (strlen($ex[2]) === 1) ? '0'.$ex[2] : $ex[2];
-		}
-		else
-		{
-			// Unless specified, seconds get set to zero.
-			$sec = '00';
-		}
+		$hour	= (int) $ex[0];
+		$min	= (int) $ex[1];
+		$sec	= ( ! empty($ex[2]) && preg_match('/[0-9]{1,2}/', $ex[2]))
+				? (int) $ex[2] : 0;
 
 		if (isset($split[2]))
 		{
 			$ampm = strtolower($split[2]);
 
-			if (substr($ampm, 0, 1) === 'p' && $hour < 12)
+			if ($ampm[0] === 'p' && $hour < 12)
 			{
 				$hour += 12;
 			}
-
-			if (substr($ampm, 0, 1) === 'a' && $hour == 12)
+			elseif ($ampm[0] === 'a' && $hour === 12)
 			{
-				$hour =  '00';
-			}
-
-			if (strlen($hour) === 1)
-			{
-				$hour = '0'.$hour;
+				$hour = 0;
 			}
 		}
 
@@ -526,7 +490,7 @@ if ( ! function_exists('nice_date'))
 		}
 
 		// Date like: YYYYMM
-		if (preg_match('/^\d{6}$/', $bad_date))
+		if (preg_match('/^\d{6}$/i', $bad_date))
 		{
 			if (in_array(substr($bad_date, 0, 2), array('19', '20')))
 			{
@@ -543,20 +507,15 @@ if ( ! function_exists('nice_date'))
 		}
 
 		// Date Like: YYYYMMDD
-		if (preg_match('/^\d{8}$/', $bad_date))
+		if (preg_match('/^(\d{2})\d{2}(\d{4})$/i', $bad_date, $matches))
 		{
-			$month = substr($bad_date, 0, 2);
-			$day   = substr($bad_date, 2, 2);
-			$year  = substr($bad_date, 4, 4);
-
-			return date($format, strtotime($month.'/01/'.$year));
+			return date($format, strtotime($matches[1].'/01/'.$matches[2]));
 		}
 
 		// Date Like: MM-DD-YYYY __or__ M-D-YYYY (or anything in between)
-		if (preg_match('/^\d{1,2}-\d{1,2}-\d{4}$/', $bad_date))
+		if (preg_match('/^(\d{1,2})-(\d{1,2})-(\d{4})$/i', $bad_date, $matches))
 		{
-			list($m, $d, $y) = explode('-', $bad_date);
-			return date($format, strtotime($y.'-'.$m.'-'.$d));
+			return date($format, strtotime($matches[3].'-'.$matches[1].'-'.$matches[2]));
 		}
 
 		// Any other kind of string, when converted into UNIX time,
@@ -678,8 +637,6 @@ if ( ! function_exists('timezones'))
 			return $zones;
 		}
 
-		$tz = ($tz === 'GMT') ? 'UTC' : $tz;
-
 		return isset($zones[$tz]) ? $zones[$tz] : 0;
 	}
 }
diff --git a/system/helpers/download_helper.php b/system/helpers/download_helper.php
index 3c677055f..5efbc4930 100644
--- a/system/helpers/download_helper.php
+++ b/system/helpers/download_helper.php
@@ -73,14 +73,7 @@ if ( ! function_exists('force_download'))
 			}
 
 			// Load the mime types
-			if (defined('ENVIRONMENT') && is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
-			{
-				$mimes = include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
-			}
-			elseif (is_file(APPPATH.'config/mimes.php'))
-			{
-				$mimes = include(APPPATH.'config/mimes.php');
-			}
+			$mimes =& get_mimes();
 
 			// Only change the default MIME if we can find one
 			if (isset($mimes[$extension]))
diff --git a/system/helpers/file_helper.php b/system/helpers/file_helper.php
index 068706c30..be616f62d 100644
--- a/system/helpers/file_helper.php
+++ b/system/helpers/file_helper.php
@@ -44,38 +44,15 @@ if ( ! function_exists('read_file'))
 	 *
 	 * Opens the file specfied in the path and returns it as a string.
 	 *
+	 * This function is DEPRECATED and should be removed in
+	 * CodeIgniter 3.1+. Use file_get_contents() instead.
+	 *
 	 * @param	string	path to file
 	 * @return	string
 	 */
 	function read_file($file)
 	{
-		if ( ! file_exists($file))
-		{
-			return FALSE;
-		}
-
-		if (function_exists('file_get_contents'))
-		{
-			return file_get_contents($file);
-		}
-
-		if ( ! $fp = @fopen($file, FOPEN_READ))
-		{
-			return FALSE;
-		}
-
-		flock($fp, LOCK_SH);
-
-		$data = '';
-		if (filesize($file) > 0)
-		{
-			$data =& fread($fp, filesize($file));
-		}
-
-		flock($fp, LOCK_UN);
-		fclose($fp);
-
-		return $data;
+		return @file_get_contents($file);
 	}
 }
 
@@ -353,32 +330,19 @@ if ( ! function_exists('get_mime_by_extension'))
 
 		if ( ! is_array($mimes))
 		{
-			if (defined('ENVIRONMENT') && is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
-			{
-				$mimes = include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
-			}
-			elseif (is_file(APPPATH.'config/mimes.php'))
-			{
-				$mimes = include(APPPATH.'config/mimes.php');
-			}
+			$mimes =& get_mimes();
 
-			if ( ! is_array($mimes))
+			if (empty($mimes))
 			{
 				return FALSE;
 			}
 		}
 
-		if (array_key_exists($extension, $mimes))
+		if (isset($mimes[$extension]))
 		{
-			if (is_array($mimes[$extension]))
-			{
-				// Multiple mime types, just give the first one
-				return current($mimes[$extension]);
-			}
-			else
-			{
-				return $mimes[$extension];
-			}
+			return is_array($mimes[$extension])
+				? current($mimes[$extension]) // Multiple mime types, just give the first one
+				: $mimes[$extension];
 		}
 
 		return FALSE;
diff --git a/system/helpers/form_helper.php b/system/helpers/form_helper.php
index 410972187..984634315 100644
--- a/system/helpers/form_helper.php
+++ b/system/helpers/form_helper.php
@@ -325,7 +325,10 @@ if ( ! function_exists('form_dropdown'))
 			$selected = array($_POST[$name]);
 		}
 
-		if ($extra !== '') $extra = ' '.$extra;
+		if ($extra != '')
+		{
+			$extra = ' '.$extra;
+		}
 
 		$multiple = (count($selected) > 1 && strpos($extra, 'multiple') === FALSE) ? ' multiple="multiple"' : '';
 
@@ -378,7 +381,7 @@ if ( ! function_exists('form_checkbox'))
 		{
 			$checked = $data['checked'];
 
-			if ($checked === FALSE)
+			if ($checked == FALSE)
 			{
 				unset($data['checked']);
 			}
@@ -388,7 +391,7 @@ if ( ! function_exists('form_checkbox'))
 			}
 		}
 
-		if ($checked === TRUE)
+		if ($checked == TRUE)
 		{
 			$defaults['checked'] = 'checked';
 		}
@@ -702,7 +705,7 @@ if ( ! function_exists('set_select'))
 					return '';
 				}
 			}
-			elseif (($field === '' OR $value === '') OR ($field !== $value))
+			elseif (($field == '' OR $value == '') OR $field !== $value)
 			{
 				return '';
 			}
@@ -753,7 +756,7 @@ if ( ! function_exists('set_checkbox'))
 					return '';
 				}
 			}
-			elseif (($field === '' OR $value === '') OR ($field !== $value))
+			elseif (($field == '' OR $value == '') OR $field !== $value)
 			{
 				return '';
 			}
@@ -806,7 +809,7 @@ if ( ! function_exists('set_radio'))
 			}
 			else
 			{
-				if (($field === '' OR $value === '') OR ($field !== $value))
+				if (($field == '' OR $value == '') OR $field !== $value)
 				{
 					return '';
 				}
diff --git a/system/helpers/path_helper.php b/system/helpers/path_helper.php
index 13410545c..fec4a1a10 100644
--- a/system/helpers/path_helper.php
+++ b/system/helpers/path_helper.php
@@ -55,7 +55,7 @@ if ( ! function_exists('set_realpath'))
 		}
 
 		// Resolve the path
-		if (function_exists('realpath') && @realpath($path) !== FALSE)
+		if (@realpath($path) !== FALSE)
 		{
 			$path = realpath($path);
 		}
diff --git a/system/helpers/security_helper.php b/system/helpers/security_helper.php
index 6187a4a7a..3e6e91435 100644
--- a/system/helpers/security_helper.php
+++ b/system/helpers/security_helper.php
@@ -77,6 +77,9 @@ if ( ! function_exists('do_hash'))
 	/**
 	 * Hash encode a string
 	 *
+	 * This function is DEPRECATED and should be removed in
+	 * CodeIgniter 3.1+. Use hash() instead.
+	 *
 	 * @param	string
 	 * @param	string
 	 * @return	string
diff --git a/system/language/english/calendar_lang.php b/system/language/english/calendar_lang.php
index 2d477e6c8..48939d476 100644
--- a/system/language/english/calendar_lang.php
+++ b/system/language/english/calendar_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/date_lang.php b/system/language/english/date_lang.php
index 533563700..38532b76f 100644
--- a/system/language/english/date_lang.php
+++ b/system/language/english/date_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/db_lang.php b/system/language/english/db_lang.php
index a135d1aac..479cbb167 100644
--- a/system/language/english/db_lang.php
+++ b/system/language/english/db_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/email_lang.php b/system/language/english/email_lang.php
index 23296a244..95a16d12b 100644
--- a/system/language/english/email_lang.php
+++ b/system/language/english/email_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/form_validation_lang.php b/system/language/english/form_validation_lang.php
index 6cf0b46f4..eb4624e07 100644
--- a/system/language/english/form_validation_lang.php
+++ b/system/language/english/form_validation_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/ftp_lang.php b/system/language/english/ftp_lang.php
index 4e39e43bf..d00126b53 100644
--- a/system/language/english/ftp_lang.php
+++ b/system/language/english/ftp_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/imglib_lang.php b/system/language/english/imglib_lang.php
index 67ca94277..67a36e120 100644
--- a/system/language/english/imglib_lang.php
+++ b/system/language/english/imglib_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/migration_lang.php b/system/language/english/migration_lang.php
index 2085cee2a..9e3e18807 100644
--- a/system/language/english/migration_lang.php
+++ b/system/language/english/migration_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/number_lang.php b/system/language/english/number_lang.php
index 0c19ec614..429c64738 100644
--- a/system/language/english/number_lang.php
+++ b/system/language/english/number_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,11 +25,11 @@
  * @filesource
  */
 
-$lang['terabyte_abbr'] = "TB";
-$lang['gigabyte_abbr'] = "GB";
-$lang['megabyte_abbr'] = "MB";
-$lang['kilobyte_abbr'] = "KB";
-$lang['bytes'] = "Bytes";
+$lang['terabyte_abbr'] = 'TB';
+$lang['gigabyte_abbr'] = 'GB';
+$lang['megabyte_abbr'] = 'MB';
+$lang['kilobyte_abbr'] = 'KB';
+$lang['bytes'] = 'Bytes';
 
 /* End of file number_lang.php */
 /* Location: ./system/language/english/number_lang.php */
\ No newline at end of file
diff --git a/system/language/english/profiler_lang.php b/system/language/english/profiler_lang.php
index 11d791272..112527faa 100644
--- a/system/language/english/profiler_lang.php
+++ b/system/language/english/profiler_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/unit_test_lang.php b/system/language/english/unit_test_lang.php
index 3a8e14403..36e9aca30 100644
--- a/system/language/english/unit_test_lang.php
+++ b/system/language/english/unit_test_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/language/english/upload_lang.php b/system/language/english/upload_lang.php
index 4fa8394ec..c3cb9c3e8 100644
--- a/system/language/english/upload_lang.php
+++ b/system/language/english/upload_lang.php
@@ -5,9 +5,9 @@
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
diff --git a/system/libraries/Cache/Cache.php b/system/libraries/Cache/Cache.php
index 53f9f81a7..4395cf411 100644
--- a/system/libraries/Cache/Cache.php
+++ b/system/libraries/Cache/Cache.php
@@ -41,11 +41,12 @@ class CI_Cache extends CI_Driver_Library {
 	 *
 	 * @var array
 	 */
-	protected $valid_drivers = array(
+	protected $valid_drivers 	= array(
 		'cache_apc',
+		'cache_dummy',
 		'cache_file',
 		'cache_memcached',
-		'cache_dummy',
+		'cache_redis',
 		'cache_wincache'
 	);
 
diff --git a/system/libraries/Cache/drivers/Cache_file.php b/system/libraries/Cache/drivers/Cache_file.php
index ce2c2b13a..08231963e 100644
--- a/system/libraries/Cache/drivers/Cache_file.php
+++ b/system/libraries/Cache/drivers/Cache_file.php
@@ -26,7 +26,7 @@
  */
 
 /**
- * CodeIgniter Memcached Caching Class
+ * CodeIgniter File Caching Class
  *
  * @package		CodeIgniter
  * @subpackage	Libraries
@@ -71,7 +71,7 @@ class CI_Cache_file extends CI_Driver {
 			return FALSE;
 		}
 
-		$data = unserialize(read_file($this->_cache_path.$id));
+		$data = unserialize(file_get_contents($this->_cache_path.$id));
 
 		if (time() >  $data['time'] + $data['ttl'])
 		{
@@ -165,19 +165,19 @@ class CI_Cache_file extends CI_Driver {
 			return FALSE;
 		}
 
-		$data = unserialize(read_file($this->_cache_path.$id));
+		$data = unserialize(file_get_contents($this->_cache_path.$id));
 
 		if (is_array($data))
 		{
 			$mtime = filemtime($this->_cache_path.$id);
 
-			if ( ! isset($data['data']['ttl']))
+			if ( ! isset($data['ttl']))
 			{
 				return FALSE;
 			}
 
 			return array(
-				'expire' => $mtime + $data['data']['ttl'],
+				'expire' => $mtime + $data['ttl'],
 				'mtime'	 => $mtime
 			);
 		}
diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
new file mode 100644
index 000000000..e4a26b5f0
--- /dev/null
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -0,0 +1,236 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 2006 - 2012 EllisLab, Inc.
+ * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link		http://codeigniter.com
+ * @since		Version 3.0
+ * @filesource
+ */
+
+/**
+ * CodeIgniter Redis Caching Class
+ *
+ * @package	   CodeIgniter
+ * @subpackage Libraries
+ * @category   Core
+ * @author	   Anton Lindqvist <anton@qvister.se>
+ * @link
+ */
+class CI_Cache_redis extends CI_Driver
+{
+	/**
+	 * Default config
+	 *
+	 * @static
+	 * @var	array
+	 */
+	protected static $_default_config = array(
+		'host' => '127.0.0.1',
+		'password' => NULL,
+		'port' => 6379,
+		'timeout' => 0
+	);
+
+	/**
+	 * Redis connection
+	 *
+	 * @var	Redis
+	 */
+	protected $_redis;
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Get cache
+	 *
+	 * @param	string	Cache key identifier
+	 * @return	mixed
+	 */
+	public function get($key)
+	{
+		return $this->_redis->get($key);
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Save cache
+	 *
+	 * @param	string	Cache key identifier
+	 * @param	mixed	Data to save
+	 * @param	int	Time to live
+	 * @return	bool
+	 */
+	public function save($key, $value, $ttl = NULL)
+	{
+		return ($ttl)
+			? $this->_redis->setex($key, $ttl, $value)
+			: $this->_redis->set($key, $value);
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Delete from cache
+	 *
+	 * @param	string	Cache key
+	 * @return	bool
+	 */
+	public function delete($key)
+	{
+		return ($this->_redis->delete($key) === 1);
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Clean cache
+	 *
+	 * @return	bool
+	 * @see		Redis::flushDB()
+	 */
+	public function clean()
+	{
+		return $this->_redis->flushDB();
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Get cache driver info
+	 *
+	 * @param	string	Not supported in Redis.
+	 *			Only included in order to offer a
+	 *			consistent cache API.
+	 * @return	array
+	 * @see		Redis::info()
+	 */
+	public function cache_info($type = NULL)
+	{
+		return $this->_redis->info();
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Get cache metadata
+	 *
+	 * @param	string	Cache key
+	 * @return	array
+	 */
+	public function get_metadata($key)
+	{
+		$value = $this->get($key);
+
+		if ($value)
+		{
+			return array(
+				'expire' => time() + $this->_redis->ttl($key),
+				'data' => $value
+			);
+		}
+
+		return FALSE;
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Check if Redis driver is supported
+	 *
+	 * @return	bool
+	 */
+	public function is_supported()
+	{
+		if (extension_loaded('redis'))
+		{
+			$this->_setup_redis();
+			return TRUE;
+		}
+		else
+		{
+			log_message('error', 'The Redis extension must be loaded to use Redis cache.');
+			return FALSE;
+		}
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Setup Redis config and connection
+	 *
+	 * Loads Redis config file if present. Will halt execution
+	 * if a Redis connection can't be established.
+	 *
+	 * @return	bool
+	 * @see		Redis::connect()
+	 */
+	protected function _setup_redis()
+	{
+		$config = array();
+		$CI =& get_instance();
+
+		if ($CI->config->load('redis', TRUE, TRUE))
+		{
+			$config += $CI->config->item('redis');
+		}
+
+		$config = array_merge(self::$_default_config, $config);
+
+		$this->_redis = new Redis();
+
+		try
+		{
+			$this->_redis->connect($config['host'], $config['port'], $config['timeout']);
+		}
+		catch (RedisException $e)
+		{
+			show_error('Redis connection refused. ' . $e->getMessage());
+		}
+
+		if (isset($config['password']))
+		{
+			$this->_redis->auth($config['password']);
+		}
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+
+	 * Class destructor
+	 *
+	 * Closes the connection to Redis if present.
+	 *
+	 * @return	void
+	 */
+	public function __destruct()
+	{
+		if ($this->_redis)
+		{
+			$this->_redis->close();
+		}
+	}
+
+}
+
+/* End of file Cache_redis.php */
+/* Location: ./system/libraries/Cache/drivers/Cache_redis.php */
\ No newline at end of file
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index 45866797b..dd5477e05 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -166,8 +166,8 @@ class CI_Email {
 		$this->_headers		= array();
 		$this->_debug_msg	= array();
 
-		$this->_set_header('User-Agent', $this->useragent);
-		$this->_set_header('Date', $this->_set_date());
+		$this->set_header('User-Agent', $this->useragent);
+		$this->set_header('Date', $this->_set_date());
 
 		if ($clear_attachments !== FALSE)
 		{
@@ -215,8 +215,8 @@ class CI_Email {
 			}
 		}
 
-		$this->_set_header('From', $name.' <'.$from.'>');
-		$this->_set_header('Return-Path', '<'.$from.'>');
+		$this->set_header('From', $name.' <'.$from.'>');
+		$this->set_header('Return-Path', '<'.$from.'>');
 
 		return $this;
 	}
@@ -247,12 +247,12 @@ class CI_Email {
 			$name = $replyto;
 		}
 
-		if (strncmp($name, '"', 1) !== 0)
+		if (strpos($name, '"') !== 0)
 		{
 			$name = '"'.$name.'"';
 		}
 
-		$this->_set_header('Reply-To', $name.' <'.$replyto.'>');
+		$this->set_header('Reply-To', $name.' <'.$replyto.'>');
 		$this->_replyto_flag = TRUE;
 
 		return $this;
@@ -278,7 +278,7 @@ class CI_Email {
 
 		if ($this->_get_protocol() !== 'mail')
 		{
-			$this->_set_header('To', implode(', ', $to));
+			$this->set_header('To', implode(', ', $to));
 		}
 
 		switch ($this->_get_protocol())
@@ -312,7 +312,7 @@ class CI_Email {
 			$this->validate_email($cc);
 		}
 
-		$this->_set_header('Cc', implode(', ', $cc));
+		$this->set_header('Cc', implode(', ', $cc));
 
 		if ($this->_get_protocol() === 'smtp')
 		{
@@ -352,7 +352,7 @@ class CI_Email {
 		}
 		else
 		{
-			$this->_set_header('Bcc', implode(', ', $bcc));
+			$this->set_header('Bcc', implode(', ', $bcc));
 		}
 
 		return $this;
@@ -369,7 +369,7 @@ class CI_Email {
 	public function subject($subject)
 	{
 		$subject = $this->_prep_q_encoding($subject);
-		$this->_set_header('Subject', $subject);
+		$this->set_header('Subject', $subject);
 		return $this;
 	}
 
@@ -424,7 +424,7 @@ class CI_Email {
 	 * @param	string
 	 * @return	void
 	 */
-	protected function _set_header($header, $value)
+	public function set_header($header, $value)
 	{
 		$this->_headers[$header] = $value;
 	}
@@ -606,7 +606,7 @@ class CI_Email {
 
 		foreach ($this->_base_charsets as $charset)
 		{
-			if (strncmp($charset, $this->charset, strlen($charset)) === 0)
+			if (strpos($charset, $this->charset) === 0)
 			{
 				$this->_encoding = '7bit';
 			}
@@ -651,7 +651,7 @@ class CI_Email {
 	protected function _set_date()
 	{
 		$timezone = date('Z');
-		$operator = (strncmp($timezone, '-', 1) === 0) ? '-' : '+';
+		$operator = ($timezone[0] === '-') ? '-' : '+';
 		$timezone = abs($timezone);
 		$timezone = floor($timezone/3600) * 100 + ($timezone % 3600) / 60;
 
@@ -867,11 +867,11 @@ class CI_Email {
 	 */
 	protected function _build_headers()
 	{
-		$this->_set_header('X-Sender', $this->clean_email($this->_headers['From']));
-		$this->_set_header('X-Mailer', $this->useragent);
-		$this->_set_header('X-Priority', $this->_priorities[$this->priority - 1]);
-		$this->_set_header('Message-ID', $this->_get_message_id());
-		$this->_set_header('Mime-Version', '1.0');
+		$this->set_header('X-Sender', $this->clean_email($this->_headers['From']));
+		$this->set_header('X-Mailer', $this->useragent);
+		$this->set_header('X-Priority', $this->_priorities[$this->priority - 1]);
+		$this->set_header('Message-ID', $this->_get_message_id());
+		$this->set_header('Mime-Version', '1.0');
 	}
 
 	// --------------------------------------------------------------------
@@ -1305,7 +1305,7 @@ class CI_Email {
 
 			if ($this->protocol !== 'smtp')
 			{
-				$this->_set_header('Bcc', implode(', ', $bcc));
+				$this->set_header('Bcc', implode(', ', $bcc));
 			}
 			else
 			{
@@ -1481,7 +1481,7 @@ class CI_Email {
 
 		$this->_set_error_message($reply);
 
-		if (strncmp($reply, '250', 3) !== 0)
+		if (strpos($reply, '250') !== 0)
 		{
 			$this->_set_error_message('lang:email_smtp_error', $reply);
 			return FALSE;
@@ -1599,7 +1599,7 @@ class CI_Email {
 
 		$this->_debug_msg[] = '<pre>'.$cmd.': '.$reply.'</pre>';
 
-		if (substr($reply, 0, 3) !== $resp)
+		if ( (int) substr($reply, 0, 3) !== $resp)
 		{
 			$this->_set_error_message('lang:email_smtp_error', $reply);
 			return FALSE;
@@ -1637,7 +1637,7 @@ class CI_Email {
 
 		$reply = $this->_get_smtp_data();
 
-		if (strncmp($reply, '334', 3) !== 0)
+		if (strpos($reply, '334') !== 0)
 		{
 			$this->_set_error_message('lang:email_failed_smtp_login', $reply);
 			return FALSE;
@@ -1647,7 +1647,7 @@ class CI_Email {
 
 		$reply = $this->_get_smtp_data();
 
-		if (strncmp($reply, '334', 3) !== 0)
+		if (strpos($reply, '334') !== 0)
 		{
 			$this->_set_error_message('lang:email_smtp_auth_un', $reply);
 			return FALSE;
@@ -1657,7 +1657,7 @@ class CI_Email {
 
 		$reply = $this->_get_smtp_data();
 
-		if (strncmp($reply, '235', 3) !== 0)
+		if (strpos($reply, '235') !== 0)
 		{
 			$this->_set_error_message('lang:email_smtp_auth_pw', $reply);
 			return FALSE;
@@ -1816,98 +1816,23 @@ class CI_Email {
 	 */
 	protected function _mime_types($ext = '')
 	{
-		$mimes = array(
-						'hqx'	=>	'application/mac-binhex40',
-						'cpt'	=>	'application/mac-compactpro',
-						'doc'	=>	'application/msword',
-						'bin'	=>	'application/macbinary',
-						'dms'	=>	'application/octet-stream',
-						'lha'	=>	'application/octet-stream',
-						'lzh'	=>	'application/octet-stream',
-						'exe'	=>	'application/octet-stream',
-						'class'	=>	'application/octet-stream',
-						'psd'	=>	'application/octet-stream',
-						'so'	=>	'application/octet-stream',
-						'sea'	=>	'application/octet-stream',
-						'dll'	=>	'application/octet-stream',
-						'oda'	=>	'application/oda',
-						'pdf'	=>	'application/pdf',
-						'ai'	=>	'application/postscript',
-						'eps'	=>	'application/postscript',
-						'ps'	=>	'application/postscript',
-						'smi'	=>	'application/smil',
-						'smil'	=>	'application/smil',
-						'mif'	=>	'application/vnd.mif',
-						'xls'	=>	'application/vnd.ms-excel',
-						'ppt'	=>	'application/vnd.ms-powerpoint',
-						'wbxml'	=>	'application/vnd.wap.wbxml',
-						'wmlc'	=>	'application/vnd.wap.wmlc',
-						'dcr'	=>	'application/x-director',
-						'dir'	=>	'application/x-director',
-						'dxr'	=>	'application/x-director',
-						'dvi'	=>	'application/x-dvi',
-						'gtar'	=>	'application/x-gtar',
-						'php'	=>	'application/x-httpd-php',
-						'php4'	=>	'application/x-httpd-php',
-						'php3'	=>	'application/x-httpd-php',
-						'phtml'	=>	'application/x-httpd-php',
-						'phps'	=>	'application/x-httpd-php-source',
-						'js'	=>	'application/x-javascript',
-						'swf'	=>	'application/x-shockwave-flash',
-						'sit'	=>	'application/x-stuffit',
-						'tar'	=>	'application/x-tar',
-						'tgz'	=>	'application/x-tar',
-						'xhtml'	=>	'application/xhtml+xml',
-						'xht'	=>	'application/xhtml+xml',
-						'zip'	=>	'application/zip',
-						'mid'	=>	'audio/midi',
-						'midi'	=>	'audio/midi',
-						'mpga'	=>	'audio/mpeg',
-						'mp2'	=>	'audio/mpeg',
-						'mp3'	=>	'audio/mpeg',
-						'aif'	=>	'audio/x-aiff',
-						'aiff'	=>	'audio/x-aiff',
-						'aifc'	=>	'audio/x-aiff',
-						'ram'	=>	'audio/x-pn-realaudio',
-						'rm'	=>	'audio/x-pn-realaudio',
-						'rpm'	=>	'audio/x-pn-realaudio-plugin',
-						'ra'	=>	'audio/x-realaudio',
-						'rv'	=>	'video/vnd.rn-realvideo',
-						'wav'	=>	'audio/x-wav',
-						'bmp'	=>	'image/bmp',
-						'gif'	=>	'image/gif',
-						'jpeg'	=>	'image/jpeg',
-						'jpg'	=>	'image/jpeg',
-						'jpe'	=>	'image/jpeg',
-						'png'	=>	'image/png',
-						'tiff'	=>	'image/tiff',
-						'tif'	=>	'image/tiff',
-						'css'	=>	'text/css',
-						'ics'	=>	'text/calendar',
-						'html'	=>	'text/html',
-						'htm'	=>	'text/html',
-						'shtml'	=>	'text/html',
-						'txt'	=>	'text/plain',
-						'text'	=>	'text/plain',
-						'log'	=>	'text/plain',
-						'rtx'	=>	'text/richtext',
-						'rtf'	=>	'text/rtf',
-						'xml'	=>	'text/xml',
-						'xsl'	=>	'text/xml',
-						'mpeg'	=>	'video/mpeg',
-						'mpg'	=>	'video/mpeg',
-						'mpe'	=>	'video/mpeg',
-						'qt'	=>	'video/quicktime',
-						'mov'	=>	'video/quicktime',
-						'avi'	=>	'video/x-msvideo',
-						'movie'	=>	'video/x-sgi-movie',
-						'doc'	=>	'application/msword',
-						'word'	=>	'application/msword',
-						'xl'	=>	'application/excel',
-						'eml'	=>	'message/rfc822'
-					);
-
-		return isset($mimes[strtolower($ext)]) ? $mimes[strtolower($ext)] : 'application/x-unknown-content-type';
+		static $mimes;
+
+		$ext = strtolower($ext);
+
+		if ( ! is_array($mimes))
+		{
+			$mimes =& get_mimes();
+		}
+
+		if (isset($mimes[$ext]))
+		{
+			return is_array($mimes[$ext])
+				? current($mimes[$ext])
+				: $mimes[$ext];
+		}
+
+		return 'application/x-unknown-content-type';
 	}
 
 }
diff --git a/system/libraries/Encrypt.php b/system/libraries/Encrypt.php
index 959e2eea8..8ffd93aea 100644
--- a/system/libraries/Encrypt.php
+++ b/system/libraries/Encrypt.php
@@ -104,8 +104,7 @@ class CI_Encrypt {
 				return $this->encryption_key;
 			}
 
-			$CI =& get_instance();
-			$key = $CI->config->item('encryption_key');
+			$key = config_item('encryption_key');
 
 			if ($key === FALSE)
 			{
@@ -214,6 +213,7 @@ class CI_Encrypt {
 		$dec = base64_decode($string);
 		if (($dec = $this->mcrypt_decode($dec, $key)) === FALSE)
 		{
+			$this->set_mode($current_mode);
 			return FALSE;
 		}
 
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index 225325d6f..6cbe032c7 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -187,6 +187,12 @@ class CI_Form_validation {
 			return $this;
 		}
 
+		// Convert an array of rules to a string
+		if (is_array($rules))
+		{
+			$rules = implode('|', $rules);
+		}
+
 		// No fields? Nothing to do...
 		if ( ! is_string($field) OR ! is_string($rules) OR $field === '')
 		{
@@ -1089,11 +1095,12 @@ class CI_Form_validation {
 	 * Validate IP Address
 	 *
 	 * @param	string
+	 * @param	string	'ipv4' or 'ipv6' to validate a specific IP format
 	 * @return	bool
 	 */
-	public function valid_ip($ip)
+	public function valid_ip($ip, $which = '')
 	{
-		return $this->CI->input->valid_ip($ip);
+		return $this->CI->input->valid_ip($ip, $which);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Javascript.php b/system/libraries/Javascript.php
index 98fec61d3..5c8b09217 100644
--- a/system/libraries/Javascript.php
+++ b/system/libraries/Javascript.php
@@ -620,7 +620,7 @@ class CI_Javascript {
 			$this->_javascript_location = $this->CI->config->item('javascript_location');
 		}
 
-		if ($relative === TRUE OR strncmp($external_file, 'http://', 7) === 0 OR strncmp($external_file, 'https://', 8) === 0)
+		if ($relative === TRUE OR strpos($external_file, 'http://') === 0 OR strpos($external_file, 'https://') === 0)
 		{
 			$str = $this->_open_script($external_file);
 		}
diff --git a/system/libraries/Pagination.php b/system/libraries/Pagination.php
index a91159c98..cdec736ff 100644
--- a/system/libraries/Pagination.php
+++ b/system/libraries/Pagination.php
@@ -36,38 +36,39 @@
  */
 class CI_Pagination {
 
-	protected $base_url				= ''; // The page we are linking to
-	protected $prefix				= ''; // A custom prefix added to the path.
-	protected $suffix				= ''; // A custom suffix added to the path.
-	protected $total_rows			= 0; // Total number of items (database results)
-	protected $per_page				= 10; // Max number of items you want shown per page
-	protected $num_links			= 2; // Number of "digit" links to show before/after the currently viewed page
-	protected $cur_page				= 0; // The current page being viewed
-	protected $use_page_numbers		= FALSE; // Use page number for segment instead of offset
-	protected $first_link			= '&lsaquo; First';
-	protected $next_link			= '&gt;';
-	protected $prev_link			= '&lt;';
-	protected $last_link			= 'Last &rsaquo;';
-	protected $uri_segment			= 3;
-	protected $full_tag_open		= '';
-	protected $full_tag_close		= '';
-	protected $first_tag_open		= '';
-	protected $first_tag_close		= '&nbsp;';
-	protected $last_tag_open		= '&nbsp;';
-	protected $last_tag_close		= '';
-	protected $first_url			= ''; // Alternative URL for the First Page.
-	protected $cur_tag_open			= '&nbsp;<strong>';
-	protected $cur_tag_close		= '</strong>';
-	protected $next_tag_open		= '&nbsp;';
-	protected $next_tag_close		= '&nbsp;';
-	protected $prev_tag_open		= '&nbsp;';
-	protected $prev_tag_close		= '';
-	protected $num_tag_open			= '&nbsp;';
-	protected $num_tag_close		= '';
-	protected $page_query_string	= FALSE;
-	protected $query_string_segment = 'per_page';
-	protected $display_pages		= TRUE;
-	protected $anchor_class			= '';
+	public $base_url				= ''; // The page we are linking to
+	public $prefix				= ''; // A custom prefix added to the path.
+	public $suffix				= ''; // A custom suffix added to the path.
+	public $total_rows			= 0; // Total number of items (database results)
+	public $per_page				= 10; // Max number of items you want shown per page
+	public $num_links			= 2; // Number of "digit" links to show before/after the currently viewed page
+	public $cur_page				= 0; // The current page being viewed
+	public $use_page_numbers		= FALSE; // Use page number for segment instead of offset
+	public $first_link			= '&lsaquo; First';
+	public $next_link			= '&gt;';
+	public $prev_link			= '&lt;';
+	public $last_link			= 'Last &rsaquo;';
+	public $uri_segment			= 3;
+	public $full_tag_open		= '';
+	public $full_tag_close		= '';
+	public $first_tag_open		= '';
+	public $first_tag_close		= '&nbsp;';
+	public $last_tag_open		= '&nbsp;';
+	public $last_tag_close		= '';
+	public $first_url			= ''; // Alternative URL for the First Page.
+	public $cur_tag_open			= '&nbsp;<strong>';
+	public $cur_tag_close		= '</strong>';
+	public $next_tag_open		= '&nbsp;';
+	public $next_tag_close		= '&nbsp;';
+	public $prev_tag_open		= '&nbsp;';
+	public $prev_tag_close		= '';
+	public $num_tag_open			= '&nbsp;';
+	public $num_tag_close		= '';
+	public $page_query_string	= FALSE;
+	public $query_string_segment = 'per_page';
+	public $display_pages		= TRUE;
+	public $anchor_class			= '';
+	public $attr_rel			= TRUE;
 
 	/**
 	 * Constructor
@@ -97,7 +98,7 @@ class CI_Pagination {
 			{
 				if ($key === 'anchor_class')
 				{
-					$this->anchor_class = ($val !== '') ? 'class="'.$val.'" ' : '';
+					$this->anchor_class = ($val) ? 'class="'.$val.'" ' : '';
 				}
 				elseif (isset($this->$key))
 				{
@@ -145,7 +146,7 @@ class CI_Pagination {
 
 		if ($CI->config->item('enable_query_strings') === TRUE OR $this->page_query_string === TRUE)
 		{
-			if ($CI->input->get($this->query_string_segment) !== $base_page)
+			if ($CI->input->get($this->query_string_segment) != $base_page)
 			{
 				$this->cur_page = (int) $CI->input->get($this->query_string_segment);
 			}
@@ -212,7 +213,8 @@ class CI_Pagination {
 		if ($this->first_link !== FALSE && $this->cur_page > ($this->num_links + 1))
 		{
 			$first_url = ($this->first_url === '') ? $this->base_url : $this->first_url;
-			$output .= $this->first_tag_open.'<a '.$this->anchor_class.'href="'.$first_url.'">'.$this->first_link.'</a>'.$this->first_tag_close;
+			$output .= $this->first_tag_open.'<a '.$this->anchor_class.'href="'.$first_url.'"'.$this->_attr_rel('start').'>'
+				.$this->first_link.'</a>'.$this->first_tag_close;
 		}
 
 		// Render the "previous" link
@@ -222,12 +224,14 @@ class CI_Pagination {
 
 			if ($i === $base_page && $this->first_url !== '')
 			{
-				$output .= $this->prev_tag_open.'<a '.$this->anchor_class.'href="'.$this->first_url.'">'.$this->prev_link.'</a>'.$this->prev_tag_close;
+				$output .= $this->prev_tag_open.'<a '.$this->anchor_class.'href="'.$this->first_url.'"'.$this->_attr_rel('prev').'>'
+					.$this->prev_link.'</a>'.$this->prev_tag_close;
 			}
 			else
 			{
 				$i = ($i === $base_page) ? '' : $this->prefix.$i.$this->suffix;
-				$output .= $this->prev_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$i.'">'.$this->prev_link.'</a>'.$this->prev_tag_close;
+				$output .= $this->prev_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$i.'"'.$this->_attr_rel('prev').'>'
+					.$this->prev_link.'</a>'.$this->prev_tag_close;
 			}
 
 		}
@@ -252,13 +256,15 @@ class CI_Pagination {
 
 						if ($n === '' && $this->first_url !== '')
 						{
-							$output .= $this->num_tag_open.'<a '.$this->anchor_class.'href="'.$this->first_url.'">'.$loop.'</a>'.$this->num_tag_close;
+							$output .= $this->num_tag_open.'<a '.$this->anchor_class.'href="'.$this->first_url.'"'.$this->_attr_rel('start').'>'
+								.$loop.'</a>'.$this->num_tag_close;
 						}
 						else
 						{
 							$n = ($n === '') ? '' : $this->prefix.$n.$this->suffix;
 
-							$output .= $this->num_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$n.'">'.$loop.'</a>'.$this->num_tag_close;
+							$output .= $this->num_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$n.'"'.$this->_attr_rel().'>'
+								.$loop.'</a>'.$this->num_tag_close;
 						}
 					}
 				}
@@ -270,7 +276,8 @@ class CI_Pagination {
 		{
 			$i = ($this->use_page_numbers) ? $this->cur_page + 1 : $this->cur_page * $this->per_page;
 
-			$output .= $this->next_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$this->prefix.$i.$this->suffix.'">'.$this->next_link.'</a>'.$this->next_tag_close;
+			$output .= $this->next_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$this->prefix.$i.$this->suffix.'"'.$this->_attr_rel('next').'>'
+				.$this->next_link.'</a>'.$this->next_tag_close;
 		}
 
 		// Render the "Last" link
@@ -278,7 +285,8 @@ class CI_Pagination {
 		{
 			$i = ($this->use_page_numbers) ? $num_pages : ($num_pages * $this->per_page) - $this->per_page;
 
-			$output .= $this->last_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$this->prefix.$i.$this->suffix.'">'.$this->last_link.'</a>'.$this->last_tag_close;
+			$output .= $this->last_tag_open.'<a '.$this->anchor_class.'href="'.$this->base_url.$this->prefix.$i.$this->suffix.'"'.$this->_attr_rel().'>'
+				.$this->last_link.'</a>'.$this->last_tag_close;
 		}
 
 		// Kill double slashes. Note: Sometimes we can end up with a double slash
@@ -289,6 +297,28 @@ class CI_Pagination {
 		return $this->full_tag_open.$output.$this->full_tag_close;
 	}
 
+	// --------------------------------------------------------------------
+
+	/**
+	 * Add "rel" attribute
+	 *
+	 * @param	string
+	 * @return	string
+	 */
+	protected function _attr_rel($value = '')
+	{
+		if (empty($this->attr_rel) OR ($this->attr_rel === TRUE && empty($value)))
+		{
+			return '';
+		}
+		elseif ( ! is_bool($this->attr_rel))
+		{
+			$value = $this->attr_rel;
+		}
+
+		return ' rel="'.$value.'"';
+	}
+
 }
 
 /* End of file Pagination.php */
diff --git a/system/libraries/Profiler.php b/system/libraries/Profiler.php
index aaac0c518..d96088c14 100644
--- a/system/libraries/Profiler.php
+++ b/system/libraries/Profiler.php
@@ -402,7 +402,7 @@ class CI_Profiler {
 			."\n"
 			.'<legend style="color:#5a0099;">&nbsp;&nbsp;'.$this->CI->lang->line('profiler_memory_usage')."&nbsp;&nbsp;</legend>\n"
 			.'<div style="color:#5a0099;font-weight:normal;padding:4px 0 4px 0;">'
-			.((function_exists('memory_get_usage') && ($usage = memory_get_usage()) !== '') ? number_format($usage).' bytes' : $this->CI->lang->line('profiler_no_memory'))
+			.(($usage = memory_get_usage()) != '' ? number_format($usage).' bytes' : $this->CI->lang->line('profiler_no_memory'))
 			.'</div></fieldset>';
 	}
 
diff --git a/system/libraries/Session.php b/system/libraries/Session.php
index 7beedd96b..72a942b8a 100644
--- a/system/libraries/Session.php
+++ b/system/libraries/Session.php
@@ -149,11 +149,11 @@ class CI_Session {
 	public $flashdata_key			= 'flash';
 
 	/**
-	 * Function to use to get the current time
+	 * Timezone to use for the current time
 	 *
 	 * @var string
 	 */
-	public $time_reference			= 'time';
+	public $time_reference			= 'local';
 
 	/**
 	 * Probablity level of garbage collection of old sessions
@@ -203,7 +203,7 @@ class CI_Session {
 		// manually via the $params array above or via the config file
 		foreach (array('sess_encrypt_cookie', 'sess_use_database', 'sess_table_name', 'sess_expiration', 'sess_expire_on_close', 'sess_match_ip', 'sess_match_useragent', 'sess_cookie_name', 'cookie_path', 'cookie_domain', 'cookie_secure', 'cookie_httponly', 'sess_time_to_update', 'time_reference', 'cookie_prefix', 'encryption_key') as $key)
 		{
-			$this->$key = (isset($params[$key])) ? $params[$key] : $this->CI->config->item($key);
+			$this->$key = isset($params[$key]) ? $params[$key] : $this->CI->config->item($key);
 		}
 
 		if ($this->encryption_key === '')
@@ -786,9 +786,15 @@ class CI_Session {
 	 */
 	protected function _get_time()
 	{
-		return (strtolower($this->time_reference) === 'gmt')
-			? mktime(gmdate('H'), gmdate('i'), gmdate('s'), gmdate('m'), gmdate('d'), gmdate('Y'))
-			: time();
+		if ($this->time_reference === 'local' OR $this->time_reference === date_default_timezone_get())
+		{
+			return time();
+		}
+
+		$datetime = new DateTime('now', new DateTimeZone($this->time_reference));
+		sscanf($datetime->format('j-n-Y G:i:s'), '%d-%d-%d %d:%d:%d', $day, $month, $year, $hour, $minute, $second);
+
+		return mktime($hour, $minute, $second, $month, $day, $year);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Unit_test.php b/system/libraries/Unit_test.php
index a87cf7e14..70ad8dc41 100644
--- a/system/libraries/Unit_test.php
+++ b/system/libraries/Unit_test.php
@@ -124,7 +124,7 @@ class CI_Unit_test {
 
 		$this->results[] = $report;
 
-		return($this->report($this->result($report)));
+		return $this->report($this->result($report));
 	}
 
 	// --------------------------------------------------------------------
@@ -289,15 +289,11 @@ class CI_Unit_test {
 	 */
 	protected function _backtrace()
 	{
-		if (function_exists('debug_backtrace'))
-		{
-			$back = debug_backtrace();
-			return array(
-					'file' => (isset($back[1]['file']) ? $back[1]['file'] : ''),
-					'line' => (isset($back[1]['line']) ? $back[1]['line'] : '')
-				);
-		}
-		return array('file' => 'Unknown', 'line' => 'Unknown');
+		$back = debug_backtrace();
+		return array(
+				'file' => (isset($back[1]['file']) ? $back[1]['file'] : ''),
+				'line' => (isset($back[1]['line']) ? $back[1]['line'] : '')
+			);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Upload.php b/system/libraries/Upload.php
index e31029e49..c96daaf15 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -78,6 +78,8 @@ class CI_Upload {
 			$this->initialize($props);
 		}
 
+		$this->mimes =& get_mimes();
+
 		log_message('debug', 'Upload Class Initialized');
 	}
 
@@ -113,7 +115,6 @@ class CI_Upload {
 					'image_type'			=> '',
 					'image_size_str'		=> '',
 					'error_msg'			=> array(),
-					'mimes'				=> array(),
 					'remove_spaces'			=> TRUE,
 					'xss_clean'			=> FALSE,
 					'temp_prefix'			=> 'temp_file_',
@@ -346,11 +347,12 @@ class CI_Upload {
 	 * Returns an associative array containing all of the information
 	 * related to the upload, allowing the developer easy access in one array.
 	 *
-	 * @return	array
+	 * @param	string
+	 * @return	mixed
 	 */
-	public function data()
+	public function data($index = NULL)
 	{
-		return array(
+		$data = array(
 				'file_name'		=> $this->file_name,
 				'file_type'		=> $this->file_type,
 				'file_path'		=> $this->upload_path,
@@ -366,6 +368,13 @@ class CI_Upload {
 				'image_type'		=> $this->image_type,
 				'image_size_str'	=> $this->image_size_str,
 			);
+
+		if ( ! empty($index))
+		{
+			return isset($data[$index]) ? $data[$index] : NULL;
+		}
+
+		return $data;
 	}
 
 	// --------------------------------------------------------------------
@@ -693,7 +702,7 @@ class CI_Upload {
 			return FALSE;
 		}
 
-		if (function_exists('realpath') && @realpath($this->upload_path) !== FALSE)
+		if (@realpath($this->upload_path) !== FALSE)
 		{
 			$this->upload_path = str_replace('\\', '/', realpath($this->upload_path));
 		}
@@ -814,17 +823,17 @@ class CI_Upload {
 			return FALSE;
 		}
 
-		if (function_exists('memory_get_usage') && memory_get_usage() && ini_get('memory_limit'))
+		if (memory_get_usage() && ($memory_limit = ini_get('memory_limit')))
 		{
-			$current = ini_get('memory_limit') * 1024 * 1024;
+			$memory_limit *= 1024 * 1024;
 
 			// There was a bug/behavioural change in PHP 5.2, where numbers over one million get output
 			// into scientific notation. number_format() ensures this number is an integer
 			// http://bugs.php.net/bug.php?id=43053
 
-			$new_memory = number_format(ceil(filesize($file) + $current), 0, '.', '');
+			$memory_limit = number_format(ceil(filesize($file) + $memory_limit), 0, '.', '');
 
-			ini_set('memory_limit', $new_memory); // When an integer is used, the value is measured in bytes. - PHP.net
+			ini_set('memory_limit', $memory_limit); // When an integer is used, the value is measured in bytes. - PHP.net
 		}
 
 		// If the file being uploaded is an image, then we should have no problem with XSS attacks (in theory), but
@@ -848,14 +857,8 @@ class CI_Upload {
 			// <a, <body, <head, <html, <img, <plaintext, <pre, <script, <table, <title
 			// title is basically just in SVG, but we filter it anyhow
 
-			if ( ! preg_match('/<(a|body|head|html|img|plaintext|pre|script|table|title)[\s>]/i', $opening_bytes))
-			{
-				return TRUE; // its an image, no "triggers" detected in the first 256 bytes, we're good
-			}
-			else
-			{
-				return FALSE;
-			}
+			// if its an image or no "triggers" detected in the first 256 bytes - we're good
+			return ! preg_match('/<(a|body|head|html|img|plaintext|pre|script|table|title)[\s>]/i', $opening_bytes);
 		}
 
 		if (($data = @file_get_contents($file)) === FALSE)
@@ -924,24 +927,6 @@ class CI_Upload {
 	 */
 	public function mimes_types($mime)
 	{
-		global $mimes;
-
-		if (count($this->mimes) === 0)
-		{
-			if (defined('ENVIRONMENT') && is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
-			{
-				$this->mimes = include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
-			}
-			elseif (is_file(APPPATH.'config/mimes.php'))
-			{
-				$this->mimes = include(APPPATH.'config/mimes.php');
-			}
-			else
-			{
-				return FALSE;
-			}
-		}
-
 		return isset($this->mimes[$mime]) ? $this->mimes[$mime] : FALSE;
 	}
 
diff --git a/system/libraries/Xmlrpc.php b/system/libraries/Xmlrpc.php
index 6f3542333..eac4ac118 100644
--- a/system/libraries/Xmlrpc.php
+++ b/system/libraries/Xmlrpc.php
@@ -778,7 +778,7 @@ class XML_RPC_Message extends CI_Xmlrpc
 		}
 
 		// Check for HTTP 200 Response
-		if (strncmp($data, 'HTTP', 4) === 0 && ! preg_match('/^HTTP\/[0-9\.]+ 200 /', $data))
+		if (strpos($data, 'HTTP') === 0 && ! preg_match('/^HTTP\/[0-9\.]+ 200 /', $data))
 		{
 			$errstr = substr($data, 0, strpos($data, "\n")-1);
 			return new XML_RPC_Response(0, $this->xmlrpcerr['http_error'], $this->xmlrpcstr['http_error'].' ('.$errstr.')');
diff --git a/system/libraries/Xmlrpcs.php b/system/libraries/Xmlrpcs.php
index be930b0f9..e81f2ca9a 100644
--- a/system/libraries/Xmlrpcs.php
+++ b/system/libraries/Xmlrpcs.php
@@ -303,7 +303,7 @@ class CI_Xmlrpcs extends CI_Xmlrpc
 		$methName = $m->method_name;
 
 		// Check to see if it is a system call
-		$system_call = (strncmp($methName, 'system', 5) === 0);
+		$system_call = (strpos($methName, 'system') === 0);
 
 		if ($this->xss_clean === FALSE)
 		{