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

37 files changed, 883 insertions, 870 deletions

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())
 	{