Merge upstream branch

7 files changed, 161 insertions, 226 deletions

diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index fe591dda1..b324226ab 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * Active Record Class
  *
@@ -422,7 +420,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 
 		foreach ($key as $k => $v)
 		{
-			$prefix = (count($this->ar_where) === 0 AND count($this->ar_cache_where) === 0) ? '' : $type;
+			$prefix = (count($this->ar_where) === 0 && count($this->ar_cache_where) === 0) ? '' : $type;
 
 			if (is_null($v) && ! $this->_has_operator($k))
 			{
@@ -537,7 +535,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * @param	string	The field to search
 	 * @param	array	The values searched on
-	 * @param	boolean	If the statement would be IN or NOT IN
+	 * @param	bool	If the statement would be IN or NOT IN
 	 * @param	string
 	 * @return	object
 	 */
@@ -719,7 +717,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	{
 		$type = $this->_group_get_type($type);
 		$this->ar_where_group_started = TRUE;
-		$prefix = (count($this->ar_where) === 0 AND count($this->ar_cache_where) === 0) ? '' : $type;
+		$prefix = (count($this->ar_where) === 0 && count($this->ar_cache_where) === 0) ? '' : $type;
 		$this->ar_where[] = $value = $prefix.$not.str_repeat(' ', ++$this->ar_where_group_count).' (';
 
 		if ($this->ar_caching)
@@ -984,8 +982,8 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	/**
 	 * Sets the LIMIT value
 	 *
-	 * @param	integer	the limit value
-	 * @param	integer	the offset value
+	 * @param	int	the limit value
+	 * @param	int	the offset value
 	 * @return	object
 	 */
 	public function limit($value, $offset = NULL)
@@ -1005,7 +1003,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	/**
 	 * Sets the OFFSET value
 	 *
-	 * @param	integer	the offset value
+	 * @param	int	the offset value
 	 * @return	object
 	 */
 	public function offset($offset)
@@ -1021,7 +1019,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * @param	mixed
 	 * @param	string
-	 * @param	boolean
+	 * @param	bool
 	 * @return	object
 	 */
 	public function set($key, $value = '', $escape = TRUE)
@@ -1055,9 +1053,8 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Compiles a SELECT query string and returns the sql.
 	 *
-	 * @access	public
 	 * @param	string	the table name to select from (optional)
-	 * @param	boolean	TRUE: resets AR values; FALSE: leave AR vaules alone
+	 * @param	bool	TRUE: resets AR values; FALSE: leave AR vaules alone
 	 * @return	string
 	 */
 	public function get_compiled_select($table = '', $reset = TRUE)
@@ -1226,7 +1223,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * @param	mixed
 	 * @param	string
-	 * @param	boolean
+	 * @param	bool
 	 * @return	object
 	 */
 	public function set_insert_batch($key, $value = '', $escape = TRUE)
@@ -1283,9 +1280,8 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Compiles an insert query and returns the sql
 	 *
-	 * @access	public
 	 * @param	string	the table to insert into
-	 * @param	boolean	TRUE: reset AR values; FALSE: leave AR values alone
+	 * @param	bool	TRUE: reset AR values; FALSE: leave AR values alone
 	 * @return	string
 	 */
 	public function get_compiled_insert($table = '', $reset = TRUE)
@@ -1316,7 +1312,6 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Compiles an insert string and runs the query
 	 *
-	 * @access	public
 	 * @param	string	the table to insert data into
 	 * @param	array	an associative array of insert values
 	 * @return	object
@@ -1352,7 +1347,6 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 * validate that the there data is actually being set and that table
 	 * has been chosen to be inserted into.
 	 *
-	 * @access	public
 	 * @param	string	the table to insert data into
 	 * @return	string
 	 */
@@ -1423,9 +1417,8 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Compiles an update query and returns the sql
 	 *
-	 * @access	public
 	 * @param	string	the table to update
-	 * @param	boolean	TRUE: reset AR values; FALSE: leave AR values alone
+	 * @param	bool	TRUE: reset AR values; FALSE: leave AR values alone
 	 * @return	string
 	 */
 	public function get_compiled_update($table = '', $reset = TRUE)
@@ -1499,7 +1492,6 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 * validate that data is actually being set and that a table has been
 	 * chosen to be update.
 	 *
-	 * @access	public
 	 * @param	string	the table to update data on
 	 * @return	bool
 	 */
@@ -1584,7 +1576,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * @param	array
 	 * @param	string
-	 * @param	boolean
+	 * @param	bool
 	 * @return	object
 	 */
 	public function set_update_batch($key, $index = '', $escape = TRUE)
@@ -1696,9 +1688,8 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Compiles a delete query string and returns the sql
 	 *
-	 * @access	public
 	 * @param	string	the table to delete from
-	 * @param	boolean	TRUE: reset AR values; FALSE: leave AR values alone
+	 * @param	bool	TRUE: reset AR values; FALSE: leave AR values alone
 	 * @return	string
 	 */
 	public function get_compiled_delete($table = '', $reset = TRUE)
@@ -1719,7 +1710,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 * @param	mixed	the table(s) to delete from. String or array
 	 * @param	mixed	the where clause
 	 * @param	mixed	the limit clause
-	 * @param	boolean
+	 * @param	bool
 	 * @return	object
 	 */
 	public function delete($table = '', $where = '', $limit = NULL, $reset_data = TRUE)
@@ -2062,7 +2053,6 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 	 *
 	 * Empties the AR cache
 	 *
-	 * @access	public
 	 * @return	void
 	 */
 	public function flush_cache()
@@ -2114,7 +2104,7 @@ abstract class CI_DB_active_record extends CI_DB_driver {
 
 		// If we are "protecting identifiers" we need to examine the "from"
 		// portion of the query to determine if there are any aliases
-		if ($this->_protect_identifiers === TRUE AND count($this->ar_cache_from) > 0)
+		if ($this->_protect_identifiers === TRUE && count($this->ar_cache_from) > 0)
 		{
 			$this->_track_aliases($this->ar_from);
 		}
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 373744100..9347ce3e1 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -99,9 +99,13 @@ abstract class CI_DB_driver {
 	 */
 	public function initialize()
 	{
-		// If an existing connection resource is available
-		// there is no need to connect and select the database
-		if (is_resource($this->conn_id) OR is_object($this->conn_id))
+		/* If an established connection is available, then there's
+		 * no need to connect and select the database.
+		 *
+		 * Depending on the database driver, conn_id can be either
+		 * boolean TRUE, a resource or an object.
+		 */
+		if ($this->conn_id)
 		{
 			return TRUE;
 		}
@@ -283,17 +287,13 @@ abstract class CI_DB_driver {
 		{
 			log_message('error', 'Invalid query: '.$sql);
 
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_invalid_query');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_invalid_query') : FALSE;
 		}
 
 		// Verify table prefix and replace if necessary
-		if ( ($this->dbprefix != '' AND $this->swap_pre != '') AND ($this->dbprefix != $this->swap_pre) )
+		if ($this->dbprefix != '' && $this->swap_pre != '' && $this->dbprefix != $this->swap_pre)
 		{
-			$sql = preg_replace("/(\W)".$this->swap_pre."(\S+?)/", "\\1".$this->dbprefix."\\2", $sql);
+			$sql = preg_replace('/(\W)'.$this->swap_pre.'(\S+?)/', '\\1'.$this->dbprefix.'\\2', $sql);
 		}
 
 		// Compile binds if needed
@@ -305,15 +305,12 @@ abstract class CI_DB_driver {
 		// Is query caching enabled? If the query is a "read type"
 		// we will load the caching class and return the previously
 		// cached query if it exists
-		if ($this->cache_on == TRUE AND stristr($sql, 'SELECT'))
+		if ($this->cache_on == TRUE && stripos($sql, 'SELECT') !== FALSE && $this->_cache_init())
 		{
-			if ($this->_cache_init())
+			$this->load_rdriver();
+			if (FALSE !== ($cache = $this->CACHE->read($sql)))
 			{
-				$this->load_rdriver();
-				if (FALSE !== ($cache = $this->CACHE->read($sql)))
-				{
-					return $cache;
-				}
+				return $cache;
 			}
 		}
 
@@ -352,13 +349,7 @@ abstract class CI_DB_driver {
 				$this->trans_complete();
 
 				// Display errors
-				return $this->display_error(
-								array(
-									'Error Number: '.$error['code'],
-									$error['message'],
-									$sql
-								)
-							);
+				return $this->display_error(array('Error Number: '.$error['code'], $error['message'], $sql));
 			}
 
 			return FALSE;
@@ -382,7 +373,7 @@ abstract class CI_DB_driver {
 		{
 			// If caching is enabled we'll auto-cleanup any
 			// existing files related to this particular URI
-			if ($this->cache_on == TRUE AND $this->cache_autodel == TRUE AND $this->_cache_init())
+			if ($this->cache_on == TRUE && $this->cache_autodel == TRUE && $this->_cache_init())
 			{
 				$this->CACHE->delete();
 			}
@@ -402,9 +393,9 @@ abstract class CI_DB_driver {
 		$driver		= $this->load_rdriver();
 		$RES		= new $driver($this);
 
-		// Is query caching enabled?  If so, we'll serialize the
+		// Is query caching enabled? If so, we'll serialize the
 		// result object and save it to a cache file.
-		if ($this->cache_on == TRUE AND $this->_cache_init())
+		if ($this->cache_on == TRUE && $this->_cache_init())
 		{
 			// We'll create a new instance of the result object
 			// only without the platform specific driver since
@@ -606,7 +597,8 @@ abstract class CI_DB_driver {
 
 		// 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)) {
+		if (count($binds) >= count($segments))
+		{
 			$binds = array_slice($binds, 0, count($segments)-1);
 		}
 
@@ -615,8 +607,7 @@ abstract class CI_DB_driver {
 		$i = 0;
 		foreach ($binds as $bind)
 		{
-			$result .= $this->escape($bind);
-			$result .= $segments[++$i];
+			$result .= $this->escape($bind).$segments[++$i];
 		}
 
 		return $result;
@@ -687,15 +678,15 @@ abstract class CI_DB_driver {
 	{
 		if (is_string($str) OR method_exists($str, '__toString'))
 		{
-			$str = "'".$this->escape_str($str)."'";
+			return "'".$this->escape_str($str)."'";
 		}
 		elseif (is_bool($str))
 		{
-			$str = ($str === FALSE) ? 0 : 1;
+			return ($str === FALSE) ? 0 : 1;
 		}
 		elseif (is_null($str))
 		{
-			$str = 'NULL';
+			return 'NULL';
 		}
 
 		return $str;
@@ -731,13 +722,7 @@ abstract class CI_DB_driver {
 	public function primary($table = '')
 	{
 		$fields = $this->list_fields($table);
-
-		if ( ! is_array($fields))
-		{
-			return FALSE;
-		}
-
-		return current($fields);
+		return is_array($fields) ? current($fields) : FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -757,35 +742,40 @@ abstract class CI_DB_driver {
 
 		if (FALSE === ($sql = $this->_list_tables($constrain_by_prefix)))
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_unsupported_function');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE;
 		}
 
-		$retval = array();
+		$this->data_cache['table_names'] = array();
 		$query = $this->query($sql);
 
-		if ($query->num_rows() > 0)
+		foreach ($query->result_array() as $row)
 		{
-			$table = FALSE;
-			$rows = $query->result_array();
-			$key = (($row = current($rows)) && in_array('table_name', array_map('strtolower', array_keys($row))));
-
-			if ($key)
+			// Do we know from which column to get the table name?
+			if ( ! isset($key))
 			{
-				$table = array_key_exists('TABLE_NAME', $row) ? 'TABLE_NAME' : 'table_name';
+				if (isset($row['table_name']))
+				{
+					$key = 'table_name';
+				}
+				elseif (isset($row['TABLE_NAME']))
+				{
+					$key = 'TABLE_NAME';
+				}
+				else
+				{
+					/* We have no other choice but to just get the first element's key.
+					 * Due to array_shift() accepting it's argument by reference, if
+					 * E_STRICT is on, this would trigger a warning. So we'll have to
+					 * assign it first.
+					 */
+					$key = array_keys($row);
+					$key = array_shift($key);
+				}
 			}
 
-			foreach ($rows as $row)
-			{
-				$retval[] = ( ! $table) ? current($row) : $row[$table];
-			}
+			$this->data_cache['table_names'][] = $row[$key];
 		}
 
-		$this->data_cache['table_names'] = $retval;
-
 		return $this->data_cache['table_names'];
 	}
 
@@ -819,38 +809,45 @@ abstract class CI_DB_driver {
 
 		if ($table == '')
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_field_param_missing');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_field_param_missing') : FALSE;
 		}
 
 		if (FALSE === ($sql = $this->_list_columns($table)))
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_unsupported_function');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE;
 		}
 
 		$query = $this->query($sql);
+		$this->data_cache['field_names'][$table] = array();
 
-		$retval = array();
 		foreach ($query->result_array() as $row)
 		{
-			if (isset($row['COLUMN_NAME']))
-			{
-				$retval[] = $row['COLUMN_NAME'];
-			}
-			else
+			// Do we know from where to get the column's name?
+			if ( ! isset($key))
 			{
-				$retval[] = current($row);
+				if (isset($row['column_name']))
+				{
+					$key = 'column_name';
+				}
+				elseif (isset($row['COLUMN_NAME']))
+				{
+					$key = 'COLUMN_NAME';
+				}
+				else
+				{
+					/* We have no other choice but to just get the first element's key.
+					 * Due to array_shift() accepting it's argument by reference, if
+					 * E_STRICT is on, this would trigger a warning. So we'll have to
+					 * assign it first.
+					 */
+					$key = array_keys($row);
+					$key = array_shift($key);
+				}
 			}
+
+			$this->data_cache['field_names'][$table][] = $row[$key];
 		}
 
-		$this->data_cache['field_names'][$table] = $retval;
 		return $this->data_cache['field_names'][$table];
 	}
 
@@ -865,7 +862,7 @@ abstract class CI_DB_driver {
 	 */
 	public function field_exists($field_name, $table_name)
 	{
-		return ( ! in_array($field_name, $this->list_fields($table_name))) ? FALSE : TRUE;
+		return in_array($field_name, $this->list_fields($table_name));
 	}
 
 	// --------------------------------------------------------------------
@@ -880,15 +877,10 @@ abstract class CI_DB_driver {
 	{
 		if ($table == '')
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_field_param_missing');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_field_param_missing') : FALSE;
 		}
 
 		$query = $this->query($this->_field_data($this->protect_identifiers($table, TRUE, NULL, FALSE)));
-
 		return $query->field_data();
 	}
 
@@ -903,8 +895,7 @@ abstract class CI_DB_driver {
 	 */
 	public function insert_string($table, $data)
 	{
-		$fields = array();
-		$values = array();
+		$fields = $values = array();
 
 		foreach ($data as $key => $val)
 		{
@@ -977,13 +968,7 @@ abstract class CI_DB_driver {
 	 */
 	protected function _has_operator($str)
 	{
-		$str = trim($str);
-		if ( ! preg_match("/(\s|<|>|!|=|is null|is not null)/i", $str))
-		{
-			return FALSE;
-		}
-
-		return TRUE;
+		return (bool) preg_match('/(\s|<|>|!|=|IS NULL|IS NOT NULL)/i', trim($str));
 	}
 
 	// --------------------------------------------------------------------
@@ -1006,25 +991,12 @@ abstract class CI_DB_driver {
 
 		if ( ! function_exists($function))
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_unsupported_function');
-			}
-			return FALSE;
+			return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE;
 		}
-		else
-		{
-			$args = (func_num_args() > 1) ? array_splice(func_get_args(), 1) : null;
 
-			if (is_null($args))
-			{
-				return call_user_func($function);
-			}
-			else
-			{
-				return call_user_func_array($function, $args);
-			}
-		}
+		return (func_num_args() > 1)
+			? call_user_func_array($function, array_splice(func_get_args(), 1))
+			: call_user_func($function);
 	}
 
 	// --------------------------------------------------------------------
@@ -1049,8 +1021,7 @@ abstract class CI_DB_driver {
 	 */
 	public function cache_on()
 	{
-		$this->cache_on = TRUE;
-		return TRUE;
+		return $this->cache_on = TRUE;
 	}
 
 	// --------------------------------------------------------------------
@@ -1062,8 +1033,7 @@ abstract class CI_DB_driver {
 	 */
 	public function cache_off()
 	{
-		$this->cache_on = FALSE;
-		return FALSE;
+		return $this->cache_on = FALSE;
 	}
 
 
@@ -1076,11 +1046,9 @@ abstract class CI_DB_driver {
 	 */
 	public function cache_delete($segment_one = '', $segment_two = '')
 	{
-		if ( ! $this->_cache_init())
-		{
-			return FALSE;
-		}
-		return $this->CACHE->delete($segment_one, $segment_two);
+		return ($this->_cache_init())
+			? $this->CACHE->delete($segment_one, $segment_two)
+			: FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -1092,12 +1060,9 @@ abstract class CI_DB_driver {
 	 */
 	public function cache_delete_all()
 	{
-		if ( ! $this->_cache_init())
-		{
-			return FALSE;
-		}
-
-		return $this->CACHE->delete_all();
+		return ($this->_cache_init())
+			? $this->CACHE->delete_all()
+			: FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -1109,18 +1074,17 @@ abstract class CI_DB_driver {
 	 */
 	protected function _cache_init()
 	{
-		if (is_object($this->CACHE) AND class_exists('CI_DB_Cache'))
-		{
-			return TRUE;
-		}
-
-		if ( ! class_exists('CI_DB_Cache'))
+		if (class_exists('CI_DB_Cache'))
 		{
-			if ( ! @include(BASEPATH.'database/DB_cache.php'))
+			if (is_object($this->CACHE))
 			{
-				return $this->cache_off();
+				return TRUE;
 			}
 		}
+		elseif ( ! @include_once(BASEPATH.'database/DB_cache.php'))
+		{
+			return $this->cache_off();
+		}
 
 		$this->CACHE = new CI_DB_Cache($this); // pass db object to support multiple db connections and returned db objects
 		return TRUE;
@@ -1135,11 +1099,11 @@ abstract class CI_DB_driver {
 	 */
 	public function close()
 	{
-		if (is_resource($this->conn_id) OR is_object($this->conn_id))
+		if ($this->conn_id)
 		{
 			$this->_close($this->conn_id);
+			$this->conn_id = FALSE;
 		}
-		$this->conn_id = FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -1171,9 +1135,7 @@ abstract class CI_DB_driver {
 		// Find the most likely culprit of the error by going through
 		// the backtrace until the source file is no longer in the
 		// database folder.
-
 		$trace = debug_backtrace();
-
 		foreach ($trace as $call)
 		{
 			if (isset($call['file']) && strpos($call['file'], BASEPATH.'database') === FALSE)
@@ -1181,7 +1143,6 @@ abstract class CI_DB_driver {
 				// Found it - use a relative path for safety
 				$message[] = 'Filename: '.str_replace(array(BASEPATH, APPPATH), '', $call['file']);
 				$message[] = 'Line Number: '.$call['line'];
-
 				break;
 			}
 		}
@@ -1199,7 +1160,7 @@ abstract class CI_DB_driver {
 	 * This function is used extensively by the Active Record class, and by
 	 * a couple functions in this class.
 	 * It takes a column or table name (optionally with an alias) and inserts
-	 * the table prefix onto it.  Some logic is necessary in order to deal with
+	 * the table prefix onto it. Some logic is necessary in order to deal with
 	 * column names that include the path. Consider a query like this:
 	 *
 	 * SELECT * FROM hostname.database.table.column AS c FROM hostname.database.table
@@ -1242,12 +1203,15 @@ abstract class CI_DB_driver {
 
 		// 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
-		$alias = '';
 		if (strpos($item, ' ') !== FALSE)
 		{
-			$alias = strstr($item, " ");
+			$alias = strstr($item, ' ');
 			$item = substr($item, 0, - strlen($alias));
 		}
+		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
@@ -1282,6 +1246,7 @@ abstract class CI_DB_driver {
 
 					$item = implode('.', $parts);
 				}
+
 				return $item.$alias;
 			}
 
@@ -1316,13 +1281,12 @@ abstract class CI_DB_driver {
 				}
 
 				// Verify table prefix and replace if necessary
-				if ($this->swap_pre != '' && strncmp($parts[$i], $this->swap_pre, strlen($this->swap_pre)) === 0)
+				if ($this->swap_pre != '' && strpos($parts[$i], $this->swap_pre) === 0)
 				{
-					$parts[$i] = preg_replace("/^".$this->swap_pre."(\S+?)/", $this->dbprefix."\\1", $parts[$i]);
+					$parts[$i] = preg_replace('/^'.$this->swap_pre.'(\S+?)/', $this->dbprefix.'\\1', $parts[$i]);
 				}
-
 				// We only add the table prefix if it does not already exist
-				if (substr($parts[$i], 0, strlen($this->dbprefix)) != $this->dbprefix)
+				elseif (strpos($parts[$i], $this->dbprefix) !== 0)
 				{
 					$parts[$i] = $this->dbprefix.$parts[$i];
 				}
@@ -1343,19 +1307,18 @@ abstract class CI_DB_driver {
 		if ($this->dbprefix != '')
 		{
 			// Verify table prefix and replace if necessary
-			if ($this->swap_pre != '' && strncmp($item, $this->swap_pre, strlen($this->swap_pre)) === 0)
+			if ($this->swap_pre != '' && strpos($item, $this->swap_pre) === 0)
 			{
-				$item = preg_replace("/^".$this->swap_pre."(\S+?)/", $this->dbprefix."\\1", $item);
+				$item = preg_replace('/^'.$this->swap_pre.'(\S+?)/', $this->dbprefix.'\\1', $item);
 			}
-
 			// Do we prefix an item with no segments?
-			if ($prefix_single == TRUE AND substr($item, 0, strlen($this->dbprefix)) != $this->dbprefix)
+			elseif ($prefix_single == TRUE && strpos($item, $this->dbprefix) !== 0)
 			{
 				$item = $this->dbprefix.$item;
 			}
 		}
 
-		if ($protect_identifiers === TRUE AND ! in_array($item, $this->_reserved_identifiers))
+		if ($protect_identifiers === TRUE && ! in_array($item, $this->_reserved_identifiers))
 		{
 			$item = $this->_escape_identifiers($item);
 		}
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index f2933fe43..81af6cd72 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -52,10 +52,10 @@ class CI_DB_mssql_driver extends CI_DB {
 	/**
 	 * The syntax to count rows is slightly different across different
 	 * database engines, so this string appears in each driver and is
-	 * used for the count_all() and count_all_results() functions.
+	 * used for the count_all() and count_all_results() methods.
 	 */
 	protected $_count_string = 'SELECT COUNT(*) AS ';
-	protected $_random_keyword = ' ASC'; // not currently supported
+	protected $_random_keyword = ' NEWID()';
 
 	/**
 	 * Non-persistent database connection
@@ -539,13 +539,12 @@ class CI_DB_mssql_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific delete string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the where clause
 	 * @param	string	the limit clause
 	 * @return	string
 	 */
-	function _delete($table, $where = array(), $like = array(), $limit = FALSE)
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
 	{
 		$conditions = '';
 
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index 4c5d52127..47b0449d6 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -72,8 +72,8 @@ class CI_DB_mysqli_driver extends CI_DB {
 	public function db_connect()
 	{
 		return ($this->port != '')
-			? @mysqli_connect($this->hostname, $this->username, $this->password, $this->database, $this->port)
-			: @mysqli_connect($this->hostname, $this->username, $this->password, $this->database);
+			? @new mysqli($this->hostname, $this->username, $this->password, $this->database, $this->port)
+			: @new mysqli($this->hostname, $this->username, $this->password, $this->database);
 	}
 
 	// --------------------------------------------------------------------
@@ -92,8 +92,8 @@ class CI_DB_mysqli_driver extends CI_DB {
 		}
 
 		return ($this->port != '')
-			? @mysqli_connect('p:'.$this->hostname, $this->username, $this->password, $this->database, $this->port)
-			: @mysqli_connect('p:'.$this->hostname, $this->username, $this->password, $this->database);
+			? @new mysqli('p:'.$this->hostname, $this->username, $this->password, $this->database, $this->port)
+			: @new mysqli('p:'.$this->hostname, $this->username, $this->password, $this->database);
 	}
 
 	// --------------------------------------------------------------------
@@ -108,7 +108,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	public function reconnect()
 	{
-		if (mysqli_ping($this->conn_id) === FALSE)
+		if ($this->conn_id !== FALSE && $this->conn_id->ping() === FALSE)
 		{
 			$this->conn_id = FALSE;
 		}
@@ -129,7 +129,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 			$database = $this->database;
 		}
 
-		if (@mysqli_select_db($this->conn_id, $database))
+		if (@$this->conn_id->select_db($database))
 		{
 			$this->database = $database;
 			return TRUE;
@@ -148,7 +148,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	protected function _db_set_charset($charset)
 	{
-		return @mysqli_set_charset($this->conn_id, $charset);
+		return @$this->conn_id->set_charset($charset);
 	}
 
 	// --------------------------------------------------------------------
@@ -162,7 +162,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	{
 		return isset($this->data_cache['version'])
 			? $this->data_cache['version']
-			: $this->data_cache['version'] = @mysqli_get_server_info($this->conn_id);
+			: $this->data_cache['version'] = $this->conn_id->server_info;
 	}
 
 	// --------------------------------------------------------------------
@@ -175,7 +175,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	protected function _execute($sql)
 	{
-		return @mysqli_query($this->conn_id, $this->_prep_query($sql));
+		return @$this->conn_id->query($this->_prep_query($sql));
 	}
 
 	// --------------------------------------------------------------------
@@ -286,7 +286,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 			return $str;
 		}
 
-		$str = is_object($this->conn_id) ? mysqli_real_escape_string($this->conn_id, $str) : addslashes($str);
+		$str = is_object($this->conn_id) ? $this->conn_id->real_escape_string($str) : addslashes($str);
 
 		// escape LIKE condition wildcards
 		if ($like === TRUE)
@@ -306,7 +306,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	public function affected_rows()
 	{
-		return @mysqli_affected_rows($this->conn_id);
+		return $this->conn_id->affected_rows;
 	}
 
 	// --------------------------------------------------------------------
@@ -318,7 +318,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	public function insert_id()
 	{
-		return @mysqli_insert_id($this->conn_id);
+		return $this->conn_id->insert_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -357,7 +357,6 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
 	 *
-	 * @access	private
 	 * @param	bool
 	 * @return	string
 	 */
@@ -434,7 +433,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	public function error()
 	{
-		return array('code' => mysqli_errno($this->conn_id), 'message' => mysqli_error($this->conn_id));
+		return array('code' => $this->conn_id->errno, 'message' => $this->conn_id->error);
 	}
 
 	// --------------------------------------------------------------------
@@ -691,7 +690,8 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	protected function _close($conn_id)
 	{
-		@mysqli_close($conn_id);
+		$this->conn_id->close();
+		$this->conn_id = FALSE;
 	}
 
 }
diff --git a/system/database/drivers/mysqli/mysqli_result.php b/system/database/drivers/mysqli/mysqli_result.php
index 83d88aae3..cf0362217 100644
--- a/system/database/drivers/mysqli/mysqli_result.php
+++ b/system/database/drivers/mysqli/mysqli_result.php
@@ -43,7 +43,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 */
 	public function num_rows()
 	{
-		return @mysqli_num_rows($this->result_id);
+		return $this->result_id->num_rows;
 	}
 
 	// --------------------------------------------------------------------
@@ -55,7 +55,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 */
 	public function num_fields()
 	{
-		return @mysqli_num_fields($this->result_id);
+		return $this->result_id->field_count;
 	}
 
 	// --------------------------------------------------------------------
@@ -70,7 +70,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	public function list_fields()
 	{
 		$field_names = array();
-		while ($field = mysqli_fetch_field($this->result_id))
+		while ($field = $this->result_id->fetch_field())
 		{
 			$field_names[] = $field->name;
 		}
@@ -90,7 +90,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	public function field_data()
 	{
 		$retval = array();
-		$field_data = mysqli_fetch_fields($this->result_id);
+		$field_data = $this->result_id->fetch_fields();
 		for ($i = 0, $c = count($field_data); $i < $c; $i++)
 		{
 			$retval[$i]			= new stdClass();
@@ -115,7 +115,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	{
 		if (is_object($this->result_id))
 		{
-			mysqli_free_result($this->result_id);
+			$this->result_id->free();
 			$this->result_id = FALSE;
 		}
 	}
@@ -133,7 +133,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 */
 	protected function _data_seek($n = 0)
 	{
-		return mysqli_data_seek($this->result_id, $n);
+		return $this->result_id->data_seek($n);
 	}
 
 	// --------------------------------------------------------------------
@@ -147,7 +147,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 */
 	protected function _fetch_assoc()
 	{
-		return mysqli_fetch_assoc($this->result_id);
+		return $this->result_id->fetch_assoc();
 	}
 
 	// --------------------------------------------------------------------
@@ -161,7 +161,7 @@ class CI_DB_mysqli_result extends CI_DB_result {
 	 */
 	protected function _fetch_object()
 	{
-		return mysqli_fetch_object($this->result_id);
+		return $this->result_id->fetch_object();
 	}
 
 }
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index 19338e30f..f336eb0ab 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -484,7 +484,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 * @param	string
 	 * @return	string
 	 */
-	function count_all($table = '')
+	public function count_all($table = '')
 	{
 		if ($table == '')
 		{
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index 9f2f88699..bb4f009bc 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -55,7 +55,7 @@ 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 = ' ASC'; // not currently supported
+	protected $_random_keyword = ' NEWID()'; // not currently supported
 
 	/**
 	 * Non-persistent database connection
@@ -68,12 +68,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 		$character_set = (0 === strcasecmp('utf8', $this->char_set)) ? 'UTF-8' : $this->char_set;
 
 		$connection = array(
-			'UID'				=> empty($this->username) ? '' : $this->username,
-			'PWD'				=> empty($this->password) ? '' : $this->password,
-			'Database'			=> $this->database,
-			'ConnectionPooling' => $pooling ? 1 : 0,
+			'UID'			=> empty($this->username) ? '' : $this->username,
+			'PWD'			=> empty($this->password) ? '' : $this->password,
+			'Database'		=> $this->database,
+			'ConnectionPooling'	=> $pooling ? 1 : 0,
 			'CharacterSet'		=> $character_set,
-			'ReturnDatesAsStrings' => 1
+			'ReturnDatesAsStrings'	=> 1
 		);
 
 		// If the username and password are both empty, assume this is a
@@ -259,23 +259,6 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Parse major version
-	 *
-	 * Grabs the major version number from the
-	 * database server version string passed in.
-	 *
-	 * @param	string	$version
-	 * @return	int	major version number
-	 */
-	protected function _parse_major_version($version)
-	{
-		preg_match('/([0-9]+)\.([0-9]+)\.([0-9]+)/', $version, $ver_info);
-		return $ver_info[1]; // return the major version b/c that's all we're interested in.
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Database version number
 	 *
 	 * @return	string