Merge upstream branch

21 files changed, 1547 insertions, 366 deletions

diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 5f435e363..15195b20a 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -222,36 +222,40 @@ class CI_DB_driver {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Database Version Number.  Returns a string containing the
-	 * version of the database being used
+	 * Database version number
+	 *
+	 * Returns a string containing the version of the database being used.
+	 * Most drivers will override this method.
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function version()
+	public function version()
 	{
-		if (FALSE === ($sql = $this->_version()))
+		if (isset($this->data_cache['version']))
 		{
-			if ($this->db_debug)
-			{
-				return $this->display_error('db_unsupported_function');
-			}
-			return FALSE;
+			return $this->data_cache['version'];
 		}
 
-		// Some DBs have functions that return the version, and don't run special
-		// SQL queries per se. In these instances, just return the result.
-		$driver_version_exceptions = array('oci8', 'sqlite', 'cubrid', 'pdo', 'mysqli');
-
-		if (in_array($this->dbdriver, $driver_version_exceptions))
-		{
-			return $sql;
-		}
-		else
+		if (FALSE === ($sql = $this->_version()))
 		{
-			$query = $this->query($sql);
-			return $query->row('ver');
+			return ($this->db_debug) ? $this->display_error('db_unsupported_function') : FALSE;
 		}
+
+		$query = $this->query($sql);
+		$query = $query->row();
+		return $this->data_cache['version'] = $query->ver;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Version number query string
+	 *
+	 * @return	string
+	 */
+	protected function _version()
+	{
+		return 'SELECT VERSION() AS ver';
 	}
 
 	// --------------------------------------------------------------------
@@ -330,30 +334,28 @@ class CI_DB_driver {
 			// This will trigger a rollback if transactions are being used
 			$this->_trans_status = FALSE;
 
-			// Grab the error number and message now, as we might run some
-			// additional queries before displaying the error
-			$error_no = $this->_error_number();
-			$error_msg = $this->_error_message();
+			// Grab the error now, as we might run some additional queries before displaying the error
+			$error = $this->error();
 
 			// Log errors
-			log_message('error', 'Query error: '.$error_msg);
+			log_message('error', 'Query error: '.$error['message']);
 
 			if ($this->db_debug)
 			{
 				// We call this function in order to roll-back queries
-				// if transactions are enabled.  If we don't call this here
+				// if transactions are enabled. If we don't call this here
 				// the error message will trigger an exit, causing the
 				// transactions to remain in limbo.
 				$this->trans_complete();
 
 				// Display errors
 				return $this->display_error(
-										array(
-												'Error Number: '.$error_no,
-												$error_msg,
-												$sql
-											)
-										);
+								array(
+									'Error Number: '.$error['code'],
+									$error['message'],
+									$sql
+								)
+							);
 			}
 
 			return FALSE;
@@ -649,7 +651,7 @@ class CI_DB_driver {
 	 */
 	public function is_write_type($sql)
 	{
-		return (bool) preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|TRUNCATE|LOAD DATA|COPY|ALTER|RENAME|GRANT|REVOKE|LOCK|UNLOCK|OPTIMIZE)\s+/i', $sql);
+		return (bool) preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|TRUNCATE|LOAD DATA|COPY|ALTER|RENAME|GRANT|REVOKE|LOCK|UNLOCK|OPTIMIZE|REINDEX)\s+/i', $sql);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/cubrid/cubrid_driver.php b/system/database/drivers/cubrid/cubrid_driver.php
index 42f08fbf6..afdaef351 100644
--- a/system/database/drivers/cubrid/cubrid_driver.php
+++ b/system/database/drivers/cubrid/cubrid_driver.php
@@ -156,19 +156,15 @@ class CI_DB_cubrid_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function _version()
+	public function version()
 	{
-		// To obtain the CUBRID Server version, no need to run the SQL query.
-		// CUBRID PHP API provides a function to determin this value.
-		// This is why we also need to add 'cubrid' value to the list of
-		// $driver_version_exceptions array in DB_driver class in
-		// version() function.
-		return cubrid_get_server_info($this->conn_id);
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = cubrid_get_server_info($this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -453,31 +449,18 @@ class CI_DB_cubrid_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
-	 */
-	function _error_message()
-	{
-		return cubrid_error($this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	array
 	 */
-	function _error_number()
+	public function error()
 	{
-		return cubrid_errno($this->conn_id);
+		return array('code' => cubrid_errno($this->conn_id), 'message' => cubrid_error($this->conn_id));
 	}
 
-	// --------------------------------------------------------------------
-
 	/**
 	 * Escape the SQL Identifiers
 	 *
diff --git a/system/database/drivers/interbase/index.html b/system/database/drivers/interbase/index.html
new file mode 100644
index 000000000..c942a79ce
--- /dev/null
+++ b/system/database/drivers/interbase/index.html
@@ -0,0 +1,10 @@
+<html>
+<head>
+	<title>403 Forbidden</title>
+</head>
+<body>
+
+<p>Directory access is forbidden.</p>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/system/database/drivers/interbase/interbase_driver.php b/system/database/drivers/interbase/interbase_driver.php
new file mode 100644
index 000000000..f4bd9e271
--- /dev/null
+++ b/system/database/drivers/interbase/interbase_driver.php
@@ -0,0 +1,627 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.1.6 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 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 3.0
+ * @filesource
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * Firebird/Interbase Database Adapter Class
+ *
+ * Note: _DB is an extender class that the app controller
+ * creates dynamically based on whether the active record
+ * class is being used or not.
+ *
+ * @package		CodeIgniter
+ * @subpackage	Drivers
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		http://codeigniter.com/user_guide/database/
+ */
+class CI_DB_interbase_driver extends CI_DB {
+
+	public $dbdriver = 'interbase';
+
+	// The character used to escape with
+	protected $_escape_char = '"';
+
+	// clause and character used for LIKE escape sequences
+	protected $_like_escape_str = " ESCAPE '%s' ";
+	protected $_like_escape_chr = '!';
+
+	/**
+	 * The syntax to count rows is slightly different across different
+	 * database engines, so this string appears in each driver and is
+	 * used for the count_all() and count_all_results() functions.
+	 */
+	protected $_count_string = "SELECT COUNT(*) AS ";
+	protected $_random_keyword = ' Random()'; // database specific random keyword
+
+	// Keeps track of the resource for the current transaction
+	protected $trans;
+
+	/**
+	 * Non-persistent database connection
+	 *
+	 * @return	resource
+	 */
+	public function db_connect()
+	{
+		return @ibase_connect($this->hostname.':'.$this->database, $this->username, $this->password, $this->char_set);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Persistent database connection
+	 *
+	 * @return	resource
+	 */
+	public function db_pconnect()
+	{
+		return @ibase_pconnect($this->hostname.':'.$this->database, $this->username, $this->password, $this->char_set);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Reconnect
+	 *
+	 * Keep / reestablish the db connection if no queries have been
+	 * sent for a length of time exceeding the server's idle timeout
+	 *
+	 * @return	void
+	 */
+	public function reconnect()
+	{
+		// not implemented in Interbase/Firebird
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Select the database
+	 *
+	 * @return	bool
+	 */
+	public function db_select()
+	{
+		// Connection selects the database
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database version number
+	 *
+	 * @return	string
+	 */
+	public function version()
+	{
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		if (($service = ibase_service_attach($this->hostname, $this->username, $this->password)))
+		{
+			$this->data_cache['version'] = ibase_server_info($service, IBASE_SVC_SERVER_VERSION);
+
+			// Don't keep the service open
+			ibase_service_detach($service);
+			return $this->data_cache['version'];
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Execute the query
+	 *
+	 * @param	string	an SQL query
+	 * @return	resource
+	 */
+	protected function _execute($sql)
+	{
+		$sql = $this->_prep_query($sql);
+		return @ibase_query($this->conn_id, $sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Prep the query
+	 *
+	 * If needed, each database adapter can prep the query string
+	 *
+	 * @param	string	an SQL query
+	 * @return	string
+	 */
+	protected function _prep_query($sql)
+	{
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Begin Transaction
+	 *
+	 * @return	bool
+	 */
+	public function trans_begin($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)
+		{
+			return TRUE;
+		}
+
+		// 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;
+
+		$this->trans = @ibase_trans($this->conn_id);
+
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Commit Transaction
+	 *
+	 * @return	bool
+	 */
+	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)
+		{
+			return TRUE;
+		}
+
+		return @ibase_commit($this->trans);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Rollback Transaction
+	 *
+	 * @return	bool
+	 */
+	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)
+		{
+			return TRUE;
+		}
+
+		return @ibase_rollback($this->trans);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Escape String
+	 *
+	 * @param	string
+	 * @param	bool	whether or not the string will be used in a LIKE condition
+	 * @return	string
+	 */
+	public function escape_str($str, $like = FALSE)
+	{
+		if (is_array($str))
+		{
+			foreach ($str as $key => $val)
+			{
+				$str[$key] = $this->escape_str($val, $like);
+			}
+
+			return $str;
+		}
+
+		// escape LIKE condition wildcards
+		if ($like === TRUE)
+		{
+			$str = str_replace(	array('%', '_', $this->_like_escape_chr),
+								array($this->_like_escape_chr.'%', $this->_like_escape_chr.'_', $this->_like_escape_chr.$this->_like_escape_chr),
+								$str);
+		}
+
+		return $str;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Affected Rows
+	 *
+	 * @return	integer
+	 */
+	public function affected_rows()
+	{
+		return @ibase_affected_rows($this->conn_id);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert ID
+	 *
+	 * @param	string $generator_name
+	 * @param	integer $inc_by
+	 * @return	integer
+	 */
+	public function insert_id($generator_name, $inc_by=0)
+	{
+		//If a generator hasn't been used before it will return 0
+		return ibase_gen_id('"'.$generator_name.'"', $inc_by);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * "Count All" query
+	 *
+	 * Generates a platform-specific query string that counts all records in
+	 * the specified database
+	 *
+	 * @param	string
+	 * @return	string
+	 */
+	public function count_all($table = '')
+	{
+		if ($table == '')
+		{
+			return 0;
+		}
+
+		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . ' FROM ' . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
+
+		if ($query->num_rows() == 0)
+		{
+			return 0;
+		}
+
+		$row = $query->row();
+		$this->_reset_select();
+		return (int) $row->numrows;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * List table query
+	 *
+	 * Generates a platform-specific query string so that the table names can be fetched
+	 *
+	 * @param	boolean
+	 * @return	string
+	 */
+	protected function _list_tables($prefix_limit = FALSE)
+	{
+		$sql = <<<SQL
+			SELECT "RDB\$RELATION_NAME" FROM "RDB\$RELATIONS" 
+			WHERE "RDB\$RELATION_NAME" NOT LIKE 'RDB$%'
+			AND "RDB\$RELATION_NAME" NOT LIKE 'MON$%'
+SQL;
+
+		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		{
+			$sql .= ' AND "RDB$RELATION_NAME" LIKE \''.$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show column query
+	 *
+	 * Generates a platform-specific query string so that the column names can be fetched
+	 *
+	 * @param	string	the table name
+	 * @return	string
+	 */
+	protected function _list_columns($table = '')
+	{
+		return <<<SQL
+			SELECT "RDB\$FIELD_NAME" FROM "RDB\$RELATION_FIELDS" 
+			WHERE "RDB\$RELATION_NAME"='{$table}';
+SQL;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field data query
+	 *
+	 * Generates a platform-specific query so that the column data can be retrieved
+	 *
+	 * @param	string	the table name
+	 * @return	object
+	 */
+	protected function _field_data($table)
+	{
+		// Need to find a more efficient way to do this
+		// but Interbase/Firebird seems to lack the
+		// limit clause
+		return "SELECT * FROM {$table}";
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Error
+	 *
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
+	 *
+	 * @return	array
+	 */
+	public function error()
+	{
+		return array('code' => ibase_errcode(), 'message' => ibase_errmsg());
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Escape the SQL Identifiers
+	 *
+	 * This public function escapes column and table names
+	 *
+	 * @param	string
+	 * @return	string
+	 */
+	protected function _escape_identifiers($item)
+	{
+		foreach ($this->_reserved_identifiers as $id)
+		{
+			if (strpos($item, '.'.$id) !== FALSE)
+			{
+				$str = $this->_escape_char. str_replace('.', $this->_escape_char.'.', $item);
+
+				// remove duplicates if the user already included the escape
+				return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+			}
+		}
+
+		if (strpos($item, '.') !== FALSE)
+		{
+			$str = $this->_escape_char.str_replace('.', $this->_escape_char.'.'.$this->_escape_char, $item).$this->_escape_char;
+		}
+		else
+		{
+			$str = $this->_escape_char.$item.$this->_escape_char;
+		}
+
+		// remove duplicates if the user already included the escape
+		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * From Tables
+	 *
+	 * This public function implicitly groups FROM tables so there is no confusion
+	 * about operator precedence in harmony with SQL standards
+	 *
+	 * @param	type
+	 * @return	type
+	 */
+	protected function _from_tables($tables)
+	{
+		if ( ! is_array($tables))
+		{
+			$tables = array($tables);
+		}
+
+		//Interbase/Firebird doesn't like grouped tables
+		return implode(', ', $tables);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Insert statement
+	 *
+	 * Generates a platform-specific insert string from the supplied data
+	 *
+	 * @param	string	the table name
+	 * @param	array	the insert keys
+	 * @param	array	the insert values
+	 * @return	string
+	 */
+	protected function _insert($table, $keys, $values)
+	{
+		return "INSERT INTO {$table} (".implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	the table name
+	 * @param	array	the update data
+	 * @param	array	the where clause
+	 * @param	array	the orderby clause
+	 * @param	array	the limit clause
+	 * @return	string
+	 */
+	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
+	{
+		foreach ($values as $key => $val)
+		{
+			$valstr[] = $key." = ".$val;
+		}
+
+		//$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
+
+		$orderby = (count($orderby) >= 1)?' ORDER BY '.implode(", ", $orderby):'';
+
+		$sql = "UPDATE {$table} SET ".implode(', ', $valstr);
+
+		$sql .= ($where != '' AND count($where) >=1) ? ' WHERE '.implode(' ', $where) : '';
+
+		$sql .= $orderby;
+
+		return $sql;
+	}
+
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 * If the database does not support the truncate() command
+	 * This public function maps to "DELETE FROM table"
+	 *
+	 * @param	string	the table name
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return $this->_delete($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	the table name
+	 * @param	array	the where clause
+	 * @param	string	the limit clause
+	 * @return	string
+	 */
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
+	{
+		$conditions = '';
+
+		if (count($where) > 0 OR count($like) > 0)
+		{
+			$conditions = "\nWHERE ";
+			$conditions .= implode("\n", $this->ar_where);
+
+			if (count($where) > 0 && count($like) > 0)
+			{
+				$conditions .= ' AND ';
+			}
+			$conditions .= implode("\n", $like);
+		}
+
+		//$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
+
+		return "DELETE FROM {$table}{$conditions}";
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Limit string
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	the sql query string
+	 * @param	integer	the number of rows to limit the query to
+	 * @param	integer	the offset value
+	 * @return	string
+	 */
+	protected function _limit($sql, $limit, $offset)
+	{
+		// Keep the current sql string safe for a moment
+		$orig_sql = $sql;
+
+		// Limit clause depends on if Interbase or Firebird
+		if (stripos($this->version(), 'firebird') !== FALSE)
+		{
+			$sql = 'FIRST '. (int) $limit;
+
+			if ($offset > 0)
+			{
+				$sql .= ' SKIP '. (int) $offset;
+			}
+		}
+		else
+		{
+			$sql = 'ROWS ' . (int) $limit;
+
+			if ($offset > 0)
+			{
+				$sql = 'ROWS '. (int) $offset . ' TO ' . ($limit + $offset);
+			}
+		}
+
+		return preg_replace('`SELECT`i', "SELECT {$sql}", $orig_sql);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Close DB Connection
+	 *
+	 * @param	resource
+	 * @return	void
+	 */
+	protected function _close($conn_id)
+	{
+		@ibase_close($conn_id);
+	}
+
+}
+
+/* End of file interbase_driver.php */
+/* Location: ./system/database/drivers/interbase/interbase_driver.php */
diff --git a/system/database/drivers/interbase/interbase_forge.php b/system/database/drivers/interbase/interbase_forge.php
new file mode 100644
index 000000000..023d278ce
--- /dev/null
+++ b/system/database/drivers/interbase/interbase_forge.php
@@ -0,0 +1,243 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.1.6 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
+ * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link		http://codeigniter.com
+ * @since		Version 3.0
+ * @filesource
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * Interbase/Firebird Forge Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		http://codeigniter.com/user_guide/database/
+ */
+class CI_DB_interbase_forge extends CI_DB_forge {
+
+	/**
+	 * Create database
+	 *
+	 * @param	string	the database name
+	 * @return	string
+	 */
+	protected function _create_database($filename='')
+	{
+		// Firebird databases are flat files, so a path is required 
+		// Hostname is needed for remote access
+		return 'CREATE DATABASE "'.$this->hostname.':'.$filename.'"';
+		
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Drop database
+	 *
+	 * @param	string	the database name - not used in this driver 
+	 *	- the current db is dropped
+	 * @return	bool
+	 */
+	protected function _drop_database($name='')
+	{
+		return ibase_drop_db($this->conn_id);
+	}
+	// --------------------------------------------------------------------
+
+	/**
+	 * Create Table
+	 *
+	 * @param	string	the table name
+	 * @param	array	the fields
+	 * @param	mixed	primary key(s)
+	 * @param	mixed	key(s)
+	 * @param	boolean	should 'IF NOT EXISTS' be added to the SQL
+	 * @return	string
+	 */
+	protected function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
+	{
+		$sql = 'CREATE TABLE ';
+
+		$sql .= $this->db->protect_identifiers($table)."(";
+		$current_field_count = 0;
+
+		foreach ($fields as $field => $attributes)
+		{
+			// Numeric field names aren't allowed in databases, so if the key is
+			// numeric, we know it was assigned by PHP and the developer manually
+			// entered the field information, so we'll simply add it to the list
+			if (is_numeric($field))
+			{
+				$sql .= "\n\t$attributes";
+			}
+			else
+			{
+				$attributes = array_change_key_case($attributes, CASE_UPPER);
+
+				$sql .= "\n\t".$this->db->protect_identifiers($field);
+
+				$sql .=  ' '.$attributes['TYPE'];
+
+				if (array_key_exists('CONSTRAINT', $attributes))
+				{
+					$sql .= '('.$attributes['CONSTRAINT'].')';
+				}
+
+				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (array_key_exists('DEFAULT', $attributes))
+				{
+					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+				}
+
+				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
+				{
+					$sql .= ' NULL';
+				}
+				else
+				{
+					$sql .= ' NOT NULL';
+				}
+
+				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
+			}
+
+			// don't add a comma on the end of the last field
+			if (++$current_field_count < count($fields))
+			{
+				$sql .= ',';
+			}
+		}
+
+		if (count($primary_keys) > 0)
+		{
+			$primary_keys = $this->db->protect_identifiers($primary_keys);
+			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+		}
+
+		if (is_array($keys) && count($keys) > 0)
+		{
+			foreach ($keys as $key)
+			{
+				if (is_array($key))
+				{
+					$key = $this->db->protect_identifiers($key);
+				}
+				else
+				{
+					$key = array($this->db->protect_identifiers($key));
+				}
+
+				$sql .= ",\n\tUNIQUE (" . implode(', ', $key) . ")";
+			}
+		}
+
+		$sql .= "\n)";
+
+		return $sql;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Drop Table
+	 *
+	 * @return	string
+	 */
+	protected function _drop_table($table)
+	{
+		return 'DROP TABLE '.$name;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Alter table query
+	 *
+	 * Generates a platform-specific query so that a table can be altered
+	 * Called by add_column(), drop_column(), and column_alter(),
+	 *
+	 * @param	string	the ALTER type (ADD, DROP, CHANGE)
+	 * @param	string	the column name
+	 * @param	string	the table name
+	 * @param	string	the column definition
+	 * @param	string	the default value
+	 * @param	boolean	should 'NOT NULL' be added
+	 * @param	string	the field after which we should add the new field
+	 * @return	string
+	 */
+	protected function _alter_table($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 $sql;
+
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Rename a table
+	 *
+	 * Generates a platform-specific query so that a table can be renamed
+	 *
+	 * @param	string	the old table name
+	 * @param	string	the new table name
+	 * @return	string
+	 */
+	protected function _rename_table($table_name, $new_table_name)
+	{
+		return 'ALTER TABLE '.$this->db->protect_identifiers($table_name).' RENAME TO '.$this->db->protect_identifiers($new_table_name);
+	}
+}
+
+/* End of file interbase_forge.php */
+/* Location: ./system/database/drivers/interbase/interbase_forge.php */
\ No newline at end of file
diff --git a/system/database/drivers/interbase/interbase_result.php b/system/database/drivers/interbase/interbase_result.php
new file mode 100644
index 000000000..4b15eee20
--- /dev/null
+++ b/system/database/drivers/interbase/interbase_result.php
@@ -0,0 +1,294 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.1.6 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 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 3.0
+ * @filesource
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * Interbase/Firebird Result Class
+ *
+ * This class extends the parent result class: CI_DB_result
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		http://codeigniter.com/user_guide/database/
+ */
+class CI_DB_interbase_result extends CI_DB_result {
+
+	public $num_rows;
+
+	/**
+	 * Number of rows in the result set
+	 *
+	 * @return	integer
+	 */
+	public function num_rows()
+	{
+		if( ! is_null($this->num_rows))
+		{
+			return $this->num_rows;
+		}
+		
+		//Get the results so that you can get an accurate rowcount
+		$this->result();
+		
+		return $this->num_rows;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Number of fields in the result set
+	 *
+	 * @return	integer
+	 */
+	public function num_fields()
+	{
+		return @ibase_num_fields($this->result_id);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Fetch Field Names
+	 *
+	 * Generates an array of column names
+	 *
+	 * @return	array
+	 */
+	public function list_fields()
+	{
+		$field_names = array();
+		for ($i = 0, $num_fields = $this->num_fields(); $i < $num_fields; $i++)
+		{
+			$info = ibase_field_info($this->result_id, $i);
+			$field_names[] = $info['name'];
+		}
+
+		return $field_names;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field data
+	 *
+	 * Generates an array of objects containing field meta-data
+	 *
+	 * @return	array
+	 */
+	public function field_data()
+	{
+		
+		$retval = array();
+		for ($i = 0, $num_fields = $this->num_fields(); $i < $num_fields; $i++)
+		{
+			$info = ibase_field_info($this->result_id, $i);
+		
+			$F				= new stdClass();
+			$F->name		= $info['name'];
+			$F->type		= $info['type'];
+			$F->max_length	= $info['length'];
+			$F->primary_key = 0;
+			$F->default		= '';
+
+			$retval[] = $F;
+		}
+
+		return $retval;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Free the result
+	 *
+	 * @return	null
+	 */
+	public function free_result()
+	{
+		@ibase_free_result($this->result_id);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Data Seek
+	 *
+	 * Moves the internal pointer to the desired offset.  We call
+	 * this internally before fetching results to make sure the
+	 * result set starts at zero
+	 *
+	 * @return	array
+	 */
+	protected function _data_seek($n = 0)
+	{
+		//Set the row count to 0
+		$this->num_rows = 0;
+	
+		//Interbase driver doesn't implement a suitable function
+		return FALSE;	
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Result - associative array
+	 *
+	 * Returns the result set as an array
+	 *
+	 * @return	array
+	 */
+	protected function _fetch_assoc()
+	{
+		if (($row = @ibase_fetch_assoc($this->result_id, IBASE_FETCH_BLOBS)) !== FALSE)
+		{
+			//Increment row count
+			$this->num_rows++;
+		}
+	
+		return $row;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Result - object
+	 *
+	 * Returns the result set as an object
+	 *
+	 * @return	object
+	 */
+	protected function _fetch_object()
+	{
+		if (($row = @ibase_fetch_object($this->result_id, IBASE_FETCH_BLOBS)) !== FALSE)
+		{
+			//Increment row count
+			$this->num_rows++;
+		}
+		
+		return $row;
+	}
+	
+	// --------------------------------------------------------------------
+
+	/**
+	 * Query result.  "object" version.
+	 *
+	 * @return	object
+	 */
+	public function result_object()
+	{
+		if (count($this->result_object) > 0)
+		{
+			return $this->result_object;
+		}
+		
+		// Convert result array to object so that 
+		// We don't have to get the result again
+		if (count($this->result_array) > 0)
+		{
+			$i = 0;
+		
+			foreach ($this->result_array as $array)
+			{
+				$this->result_object[$i] = new StdClass();
+			
+				foreach ($array as $key => $val)
+				{
+					$this->result_object[$i]->{$key} = $val;
+				}
+				
+				++$i;
+			}
+			
+			return $this->result_object;
+		}
+
+		// In the event that query caching is on the result_id variable
+		// will return FALSE since there isn't a valid SQL resource so
+		// we'll simply return an empty array.
+		if ($this->result_id === FALSE)
+		{
+			return array();
+		}
+
+		$this->num_rows = 0;
+		while ($row = $this->_fetch_object())
+		{
+			$this->result_object[] = $row;
+		}
+
+		return $this->result_object;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Query result.  "array" version.
+	 *
+	 * @return	array
+	 */
+	public function result_array()
+	{
+		if (count($this->result_array) > 0)
+		{
+			return $this->result_array;
+		}
+		
+		// Since the object and array are really similar, just case
+		// the result object to an array  if need be
+		if (count($this->result_object) > 0)
+		{
+			foreach ($this->result_object as $obj)
+			{
+				$this->result_array[] = (array) $obj;
+			}
+		
+			return $this->result_array;
+		}
+
+		// In the event that query caching is on the result_id variable
+		// will return FALSE since there isn't a valid SQL resource so
+		// we'll simply return an empty array.
+		if ($this->result_id === FALSE)
+		{
+			return array();
+		}
+
+		$this->num_rows = 0;
+		while ($row = $this->_fetch_assoc())
+		{
+			$this->result_array[] = $row;
+		}
+
+		return $this->result_array;
+	}
+
+}
+
+/* End of file interbase_result.php */
+/* Location: ./system/database/drivers/interbase/interbase_result.php */
\ No newline at end of file
diff --git a/system/database/drivers/interbase/interbase_utility.php b/system/database/drivers/interbase/interbase_utility.php
new file mode 100644
index 000000000..76a0497c1
--- /dev/null
+++ b/system/database/drivers/interbase/interbase_utility.php
@@ -0,0 +1,115 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.1.6 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 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 3.0
+ * @filesource
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * Interbase/Firebird Utility Class
+ *
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		http://codeigniter.com/user_guide/database/
+ */
+class CI_DB_interbase_utility extends CI_DB_utility {
+
+	/**
+	 * List databases
+	 *
+	 * I don't believe you can do a database listing with Firebird
+	 * since each database is its own file.  I suppose we could
+	 * try reading a directory looking for Firebird files, but
+	 * that doesn't seem like a terribly good idea
+	 *
+	 * @return	bool
+	 */
+	public function _list_databases()
+	{
+		if ($this->db_debug)
+		{
+			return $this->db->display_error('db_unsuported_feature');
+		}
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Optimize table query
+	 *
+	 * Is optimization even supported in Interbase/Firebird?
+	 *
+	 * @param	string	the table name
+	 * @return	object
+	 */
+	public function _optimize_table($table)
+	{
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Repair table query
+	 *
+	 * Table repairs are not supported in Interbase/Firebird
+	 *
+	 * @param	string	the table name
+	 * @return	object
+	 */
+	public function _repair_table($table)
+	{
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Interbase/Firebird Export
+	 *
+	 * @param	string	$filename
+	 * @return	mixed
+	 */
+	public function backup($filename)
+	{
+		if ($service = ibase_service_attach($this->db->hostname, $this->db->username, $this->db->password))
+		{
+			$res = ibase_backup($service, $this->db->database, $filename.'.fbk');
+			
+			//Close the service connection	
+			ibase_service_detach($service);
+			
+			return $res;
+		}
+		else
+		{
+			return FALSE;
+		}
+	}
+}
+
+/* End of file interbase_utility.php */
+/* Location: ./system/database/drivers/interbase/interbase_utility.php */
\ No newline at end of file
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index 2a4f2b575..147c63483 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -339,12 +339,11 @@ class CI_DB_mssql_driver extends CI_DB {
 	/**
 	* Version number query string
 	*
-	* @access public
-	* @return string
+	* @return	string
 	*/
-	function _version()
+	protected function _version()
 	{
-		return "SELECT @@VERSION AS ver";
+		return 'SELECT @@VERSION AS ver';
 	}
 
 	// --------------------------------------------------------------------
@@ -438,28 +437,18 @@ class CI_DB_mssql_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
-	 */
-	function _error_message()
-	{
-		return mssql_get_last_message();
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	array
 	 */
-	function _error_number()
+	public function error()
 	{
-		// Are error numbers supported?
-		return '';
+		$query = $this->query('SELECT @@ERROR AS code');
+		$query = $query->row();
+		return array('code' => $query->code, 'message' => mssql_get_last_message());
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index c88a8a766..84f7791c7 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -147,7 +147,7 @@ class CI_DB_mysql_driver extends CI_DB {
 	 * @param	string
 	 * @return	bool
 	 */
-	public function db_set_charset($charset, $collation)
+	protected function _db_set_charset($charset, $collation)
 	{
 		return function_exists('mysql_set_charset')
 			? @mysql_set_charset($charset, $this->conn_id)
@@ -157,13 +157,15 @@ class CI_DB_mysql_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
 	 * @return	string
 	 */
-	protected function _version()
+	public function version()
 	{
-		return 'SELECT version() AS ver';
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = @mysql_get_server_info($this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -417,25 +419,16 @@ class CI_DB_mysql_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @return	string
-	 */
-	protected function _error_message()
-	{
-		return mysql_error($this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @return	int
+	 * @return	array
 	 */
-	protected function _error_number()
+	public function error()
 	{
-		return mysql_errno($this->conn_id);
+		return array('code' => mysql_errno($this->conn_id), 'message' => mysql_error($this->conn_id));
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index dbba12e15..19353944d 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -157,13 +157,15 @@ class CI_DB_mysqli_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
 	 * @return	string
 	 */
-	protected function _version()
+	public function version()
 	{
-		return @mysqli_get_server_info($this->conn_id);
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = @mysqli_get_server_info($this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -418,25 +420,16 @@ class CI_DB_mysqli_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @return	string
-	 */
-	protected function _error_message()
-	{
-		return mysqli_error($this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @return	int
+	 * @return	array
 	 */
-	protected function _error_number()
+	public function error()
 	{
-		return mysqli_errno($this->conn_id);
+		return array('code' => mysqli_errno($this->conn_id), 'message' => mysqli_error($this->conn_id));
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index 6da6dc724..35cafff6c 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -139,14 +139,15 @@ class CI_DB_oci8_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
-	 * @access  protected
-	 * @return  string
+	 * @return	string
 	 */
-	protected function _version()
+	public function version()
 	{
-		return oci_server_version($this->conn_id);
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = oci_server_version($this->conn_id);
 	}
 
 	// --------------------------------------------------------------------
@@ -527,39 +528,18 @@ class CI_DB_oci8_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
-	 *
-	 * @return	string
-	 */
-	protected function _error_message()
-	{
-		$error = $this->_oci8_error_data();
-		return $error['message'];
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Error
 	 *
-	 * @return	string
-	 */
-	protected function _error_number()
-	{
-		$error = $this->_oci8_error_data();
-		return $error['code'];
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * OCI8-specific method to get errors.
-	 * Used by _error_message() and _error_code().
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
 	 * @return	array
 	 */
-	protected function _oci8_error_data()
+	public function error()
 	{
+		/* oci_error() returns an array that already contains the
+		 * 'code' and 'message' keys, so we can just return it.
+		 */
 		if (is_resource($this->curs_id))
 		{
 			return oci_error($this->curs_id);
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index abb660324..779b0c62f 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -124,19 +124,6 @@ class CI_DB_odbc_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
-	 *
-	 * @access	public
-	 * @return	string
-	 */
-	function _version()
-	{
-		return "SELECT version() AS ver";
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Execute the query
 	 *
 	 * @access	private called by the base class
@@ -398,27 +385,16 @@ class CI_DB_odbc_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
-	 */
-	function _error_message()
-	{
-		return odbc_errormsg($this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	array
 	 */
-	function _error_number()
+	public function error()
 	{
-		return odbc_error($this->conn_id);
+		return array('code' => odbc_error($this->conn_id), 'message' => odbc_errormsg($this->conn_id));
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index 90f0fd791..8fdfd58fb 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -289,13 +289,15 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
 	 * @return	string
 	 */
-	protected function _version()
+	public function version()
 	{
-		return $this->conn_id->getAttribute(PDO::ATTR_SERVER_VERSION);
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = $this->conn_id->getAttribute(PDO::ATTR_SERVER_VERSION);
 	}
 
 	// --------------------------------------------------------------------
@@ -499,7 +501,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function insert_id($name = NULL)
 	{
-		if ($this->pdodriver === 'pgsql' && $name === NULL && $this->_version() >= '8.1')
+		if ($this->pdodriver === 'pgsql' && $name === NULL && $this->version() >= '8.1')
 		{
 			$query = $this->query('SELECT LASTVAL() AS ins_id');
 			$query = $query->row();
@@ -609,29 +611,30 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
+	 *
+	 * @return	array
 	 */
-	function _error_message()
+	public function error()
 	{
-		$error_array = $this->conn_id->errorInfo();
+		$error = array('code' => '00000', 'message' => '');
+		$pdo_error = $this->conn_id->errorInfo();
 
-		return $error_array[2];
-	}
+		if (empty($pdo_error[0]))
+		{
+			return $error;
+		}
 
-	// --------------------------------------------------------------------
+		$error['code'] = isset($pdo_error[1]) ? $pdo_error[0].'/'.$pdo_error[1] : $pdo_error[0];
+		if (isset($pdo_error[2]))
+		{
+			 $error['message'] = $pdo_error[2];
+		}
 
-	/**
-	 * The error message number
-	 *
-	 * @access	private
-	 * @return	integer
-	 */
-	function _error_number()
-	{
-		return $this->conn_id->errorCode();
+		return $error;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 89541e5fa..df0f50da5 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -147,14 +147,43 @@ class CI_DB_postgre_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Set client character set
+	 *
+	 * @param       string
+	 * @return      bool
+	 */
+	protected function _db_set_charset($charset)
+	{
+		return (pg_set_client_encoding($this->conn_id, $charset) === 0);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database version number
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function _version()
+	public function version()
 	{
-		return "SELECT version() AS ver";
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		if (($pg_version = pg_version($this->conn_id)) === FALSE)
+		{
+			return FALSE;
+		}
+
+		/* If PHP was compiled with PostgreSQL lib versions earlier
+		 * than 7.4, pg_version() won't return the server version
+		 * and so we'll have to fall back to running a query in
+		 * order to get it.
+		 */
+		return isset($pg_version['server'])
+			? $this->data_cache['version'] = $pg_version['server']
+			: parent::version();
 	}
 
 	// --------------------------------------------------------------------
@@ -193,18 +222,12 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Begin Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_begin($test_mode = FALSE)
+	public function trans_begin($test_mode = FALSE)
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -212,9 +235,9 @@ class CI_DB_postgre_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 @pg_exec($this->conn_id, "begin");
+		return @pg_query($this->conn_id, 'BEGIN');
 	}
 
 	// --------------------------------------------------------------------
@@ -222,23 +245,17 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Commit Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_commit()
+	public function trans_commit()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		return @pg_exec($this->conn_id, "commit");
+		return @pg_query($this->conn_id, 'COMMIT');
 	}
 
 	// --------------------------------------------------------------------
@@ -246,23 +263,17 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Rollback Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_rollback()
+	public function trans_rollback()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		return @pg_exec($this->conn_id, "rollback");
+		return @pg_query($this->conn_id, 'ROLLBACK');
 	}
 
 	// --------------------------------------------------------------------
@@ -323,8 +334,7 @@ class CI_DB_postgre_driver extends CI_DB {
 	 */
 	function insert_id()
 	{
-		$v = $this->_version();
-		$v = $v['server'];
+		$v = $this->version();
 
 		$table	= func_num_args() > 0 ? func_get_arg(0) : NULL;
 		$column	= func_num_args() > 1 ? func_get_arg(1) : NULL;
@@ -443,27 +453,16 @@ class CI_DB_postgre_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
-	 */
-	function _error_message()
-	{
-		return pg_last_error($this->conn_id);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	array
 	 */
-	function _error_number()
+	public function error()
 	{
-		return '';
+		return array('code' => '', 'message' => pg_last_error($this->conn_id));
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/postgre/postgre_utility.php b/system/database/drivers/postgre/postgre_utility.php
index dffd8c549..c426b363b 100644
--- a/system/database/drivers/postgre/postgre_utility.php
+++ b/system/database/drivers/postgre/postgre_utility.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * Postgre Utility Class
  *
@@ -39,12 +37,11 @@ class CI_DB_postgre_utility extends CI_DB_utility {
 	/**
 	 * List databases
 	 *
-	 * @access	private
-	 * @return	bool
+	 * @return	string
 	 */
-	function _list_databases()
+	public function _list_databases()
 	{
-		return "SELECT datname FROM pg_database";
+		return 'SELECT datname FROM pg_database';
 	}
 
 	// --------------------------------------------------------------------
@@ -52,15 +49,12 @@ class CI_DB_postgre_utility extends CI_DB_utility {
 	/**
 	 * Optimize table query
 	 *
-	 * Is table optimization supported in Postgre?
-	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _optimize_table($table)
+	public function _optimize_table($table)
 	{
-		return FALSE;
+		return 'REINDEX TABLE '.$this->db->protect_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -68,13 +62,10 @@ class CI_DB_postgre_utility extends CI_DB_utility {
 	/**
 	 * Repair table query
 	 *
-	 * Are table repairs supported in Postgre?
-	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	bool
 	 */
-	function _repair_table($table)
+	public function _repair_table($table)
 	{
 		return FALSE;
 	}
@@ -84,7 +75,6 @@ class CI_DB_postgre_utility extends CI_DB_utility {
 	/**
 	 * Postgre Export
 	 *
-	 * @access	private
 	 * @param	array	Preferences
 	 * @return	mixed
 	 */
@@ -95,6 +85,5 @@ class CI_DB_postgre_utility extends CI_DB_utility {
 	}
 }
 
-
 /* End of file postgre_utility.php */
-/* Location: ./system/database/drivers/postgre/postgre_utility.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/postgre/postgre_utility.php */
diff --git a/system/database/drivers/sqlite/sqlite_driver.php b/system/database/drivers/sqlite/sqlite_driver.php
index 718501b20..3eaec949c 100644
--- a/system/database/drivers/sqlite/sqlite_driver.php
+++ b/system/database/drivers/sqlite/sqlite_driver.php
@@ -141,14 +141,15 @@ class CI_DB_sqlite_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * Database version number
 	 *
-	 * @access	public
 	 * @return	string
 	 */
-	function _version()
+	public function version()
 	{
-		return sqlite_libversion();
+		return isset($this->data_cache['version'])
+			? $this->data_cache['version']
+			: $this->data_cache['version'] = sqlite_libversion();
 	}
 
 	// --------------------------------------------------------------------
@@ -412,27 +413,18 @@ class CI_DB_sqlite_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @access	private
-	 * @return	string
-	 */
-	function _error_message()
-	{
-		return sqlite_error_string(sqlite_last_error($this->conn_id));
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	array
 	 */
-	function _error_number()
+	public function error()
 	{
-		return sqlite_last_error($this->conn_id);
+		$error = array('code' => sqlite_last_error($this->conn_id));
+		$error['message'] = sqlite_error_string($error['code']);
+		return $error;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/sqlite/sqlite_forge.php b/system/database/drivers/sqlite/sqlite_forge.php
index 2b723be0b..fd0f3eb98 100644
--- a/system/database/drivers/sqlite/sqlite_forge.php
+++ b/system/database/drivers/sqlite/sqlite_forge.php
@@ -89,7 +89,7 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 		$sql = 'CREATE TABLE ';
 
 		// IF NOT EXISTS added to SQLite in 3.3.0
-		if ($if_not_exists === TRUE && version_compare($this->db->_version(), '3.3.0', '>=') === TRUE)
+		if ($if_not_exists === TRUE && version_compare($this->db->version(), '3.3.0', '>=') === TRUE)
 		{
 			$sql .= 'IF NOT EXISTS ';
 		}
@@ -274,4 +274,4 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 }
 
 /* End of file sqlite_forge.php */
-/* Location: ./system/database/drivers/sqlite/sqlite_forge.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/sqlite/sqlite_forge.php */
diff --git a/system/database/drivers/sqlite/sqlite_utility.php b/system/database/drivers/sqlite/sqlite_utility.php
index f00687e38..8fefcd9e2 100644
--- a/system/database/drivers/sqlite/sqlite_utility.php
+++ b/system/database/drivers/sqlite/sqlite_utility.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * SQLite Utility Class
  *
@@ -40,20 +38,15 @@ class CI_DB_sqlite_utility extends CI_DB_utility {
 	 * List databases
 	 *
 	 * I don't believe you can do a database listing with SQLite
-	 * since each database is its own file.  I suppose we could
+	 * since each database is its own file. I suppose we could
 	 * try reading a directory looking for SQLite files, but
 	 * that doesn't seem like a terribly good idea
 	 *
-	 * @access	private
 	 * @return	bool
 	 */
-	function _list_databases()
+	public function _list_databases()
 	{
-		if ($this->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return array();
+		return ($this->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
 	}
 
 	// --------------------------------------------------------------------
@@ -61,14 +54,12 @@ class CI_DB_sqlite_utility extends CI_DB_utility {
 	/**
 	 * Optimize table query
 	 *
-	 * Is optimization even supported in SQLite?
-	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	bool
 	 */
-	function _optimize_table($table)
+	public function _optimize_table($table)
 	{
+		// Not supported
 		return FALSE;
 	}
 
@@ -77,14 +68,12 @@ class CI_DB_sqlite_utility extends CI_DB_utility {
 	/**
 	 * Repair table query
 	 *
-	 * Are table repairs even supported in SQLite?
-	 *
-	 * @access	private
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	bool
 	 */
-	function _repair_table($table)
+	public function _repair_table($table)
 	{
+		// Not supported
 		return FALSE;
 	}
 
@@ -93,16 +82,16 @@ class CI_DB_sqlite_utility extends CI_DB_utility {
 	/**
 	 * SQLite Export
 	 *
-	 * @access	private
 	 * @param	array	Preferences
 	 * @return	mixed
 	 */
-	function _backup($params = array())
+	public function _backup($params = array())
 	{
 		// Currently unsupported
 		return $this->db->display_error('db_unsuported_feature');
 	}
+
 }
 
 /* End of file sqlite_utility.php */
-/* Location: ./system/database/drivers/sqlite/sqlite_utility.php */
\ No newline at end of file
+/* Location: ./system/database/drivers/sqlite/sqlite_utility.php */
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index 9b9038189..5c90cb4f2 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -317,15 +317,23 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	* Version number query string
-	*
-	* @access public
-	* @return string
-	*/
-	function _version()
+	 * Database version number
+	 *
+	 * @return	string
+	 */
+	public function version()
 	{
-		$info = sqlsrv_server_info($this->conn_id);
-		return sprintf("select '%s' as ver", $info['SQLServerVersion']);
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		if (($info = sqlsrv_server_info($this->conn_id)) === FALSE)
+		{
+			return FALSE;
+		}
+
+		return $this->data_cache['version'] = $info['SQLServerVersion'];
 	}
 
 	// --------------------------------------------------------------------
@@ -406,46 +414,39 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message string
+	 * Error
 	 *
-	 * @return	string
+	 * Returns an array containing code and message of the last
+	 * database error that has occured.
+	 *
+	 * @return	array
 	 */
-	protected function _error_message()
+	public function error()
 	{
-		$error = sqlsrv_errors();
-		if ( ! is_array($error))
+		$error = array('code' => '00000', 'message' => '');
+		$sqlsrv_errors = sqlsrv_errors(SQLSRV_ERR_ERRORS);
+
+		if ( ! is_array($sqlsrv_errors))
 		{
-			return '';
+			return $error;
 		}
 
-		$error = array_shift($error);
-		return isset($error['message']) ? $error['message'] : '';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * The error message number
-	 *
-	 * @return	string
-	 */
-	protected function _error_number()
-	{
-		$error = sqlsrv_errors();
-		if ( ! is_array($error))
+		$sqlsrv_error = array_shift($sqlsrv_errors);
+		if (isset($sqlsrv_error['SQLSTATE']))
 		{
-			return '';
+			$error['code'] = isset($sqlsrv_error['code']) ? $sqlsrv_error['SQLSTATE'].'/'.$sqlsrv_error['code'] : $sqlsrv_error['SQLSTATE'];
 		}
-		elseif (isset($error['SQLSTATE']))
+		elseif (isset($sqlsrv_error['code']))
 		{
-			return isset($error['code']) ? $error['SQLSTATE'].'/'.$error['code'] : $error['SQLSTATE'];
+			$error['code'] = $sqlsrv_error['code'];
 		}
-		elseif (isset($error['code']))
+
+		if (isset($sqlsrv_error['message']))
 		{
-			return $error['code'];
+			$error['message'] = $sqlsrv_error['message'];
 		}
 
-		return '';
+		return $error;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index c8a5b41af..8d839d0c9 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -1359,6 +1359,7 @@ class CI_Email {
 		if ( ! $this->$method())
 		{
 			$this->_set_error_message('lang:email_send_failure_' . ($this->_get_protocol() === 'mail' ? 'phpmail' : $this->_get_protocol()));
+			return FALSE;
 		}
 
 		$this->_set_error_message('lang:email_sent', $this->_get_protocol());
@@ -1433,8 +1434,10 @@ class CI_Email {
 			return FALSE;
 		}
 
-		$this->_smtp_connect();
-		$this->_smtp_authenticate();
+		if ( ! $this->_smtp_connect() OR ! $this->_smtp_authenticate())
+		{
+			return FALSE;
+		}
 
 		$this->_send_command('from', $this->clean_email($this->_headers['From']));
 
diff --git a/system/libraries/Session.php b/system/libraries/Session.php
index 66b39a6a2..dd50a91e1 100644
--- a/system/libraries/Session.php
+++ b/system/libraries/Session.php
@@ -219,7 +219,7 @@ class CI_Session {
 				$this->CI->db->where('user_agent', $session['user_agent']);
 			}
 
-			$query = $this->CI->db->get($this->sess_table_name);
+			$query = $this->CI->db->limit(1)->get($this->sess_table_name);
 
 			// No result? Kill it!
 			if ($query->num_rows() === 0)