Merge remote-tracking branch 'upstream/develop' into new_date

4 files changed, 97 insertions, 551 deletions

diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index f336eb0ab..e25013a52 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -29,7 +29,7 @@
  * PDO Database Adapter Class
  *
  * Note: _DB is an extender class that the app controller
- * creates dynamically based on whether the active record
+ * creates dynamically based on whether the query builder
  * class is being used or not.
  *
  * @package		CodeIgniter
@@ -46,8 +46,8 @@ class CI_DB_pdo_driver extends CI_DB {
 	protected $_escape_char = '';
 
 	// clause and character used for LIKE escape sequences
-	protected $_like_escape_str;
-	protected $_like_escape_chr;
+	protected $_like_escape_str = " ESCAPE '%s' ";
+	protected $_like_escape_chr = '!';
 
 	/**
 	 * The syntax to count rows is slightly different across different
@@ -65,7 +65,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	{
 		parent::__construct($params);
 
-		if (preg_match('/([^;]+):/', $this->dsn, $match) && count($match) == 2)
+		if (preg_match('/([^;]+):/', $this->dsn, $match) && count($match) === 2)
 		{
 			// If there is a minimum valid dsn string pattern found, we're done
 			// This is for general PDO users, who tend to have a full DSN string.
@@ -79,20 +79,19 @@ class CI_DB_pdo_driver extends CI_DB {
 
 		// clause and character used for LIKE escape sequences
 		// this one depends on the driver being used
-		if ($this->pdodriver == 'mysql')
+		if ($this->pdodriver === 'mysql')
 		{
+			$this->_escape_char = '`';
 			$this->_like_escape_str = '';
-			$this->_like_escape_chr = '';
+			$this->_like_escape_chr = '\\';
 		}
-		elseif ($this->pdodriver == 'odbc')
+		elseif ($this->pdodriver === 'odbc')
 		{
 			$this->_like_escape_str = " {escape '%s'} ";
-			$this->_like_escape_chr = '!';
 		}
-		else
+		elseif ( ! in_array($this->pdodriver, array('sqlsrv', 'mssql', 'dblib', 'sybase')))
 		{
-			$this->_like_escape_str = " ESCAPE '%s' ";
-			$this->_like_escape_chr = '!';
+			$this->_escape_char = '"';
 		}
 
 		$this->trans_enabled = FALSE;
@@ -184,6 +183,8 @@ class CI_DB_pdo_driver extends CI_DB {
 	    }
 	}
 
+	// --------------------------------------------------------------------
+
 	/**
 	 * Non-persistent database connection
 	 *
@@ -191,9 +192,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function db_connect()
 	{
-		$this->options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_SILENT;
-
-		return $this->pdo_connect();
+		return $this->_pdo_connect();
 	}
 
 	// --------------------------------------------------------------------
@@ -205,10 +204,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function db_pconnect()
 	{
-		$this->options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_SILENT;
-		$this->options[PDO::ATTR_PERSISTENT] = TRUE;
-
-		return $this->pdo_connect();
+		return $this->_pdo_connect(TRUE);
 	}
 
 	// --------------------------------------------------------------------
@@ -216,20 +212,29 @@ class CI_DB_pdo_driver extends CI_DB {
 	/**
 	 * PDO connection
 	 *
+	 * @param	bool
 	 * @return	object
 	 */
-	public function pdo_connect()
+	protected function _pdo_connect($persistent = FALSE)
 	{
-		// Refer : http://php.net/manual/en/ref.pdo-mysql.connection.php
-		if ($this->pdodriver === 'mysql' && ! is_php('5.3.6'))
+		$this->options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_SILENT;
+		$persistent === FALSE OR $this->options[PDO::ATTR_PERSISTENT] = TRUE;
+
+		/* Prior to PHP 5.3.6, even if the charset was supplied in the DSN
+		 * on connect - it was ignored. This is a work-around for the issue.
+		 *
+		 * Reference: http://www.php.net/manual/en/ref.pdo-mysql.connection.php
+		 */
+		if ($this->pdodriver === 'mysql' && ! is_php('5.3.6') && ! empty($this->char_set))
 		{
-			$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] = "SET NAMES $this->char_set COLLATE '$this->dbcollat'";
+			$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] = 'SET NAMES '.$this->char_set
+					.( ! empty($this->db_collat) ? " COLLATE '".$this->dbcollat."'" : '');
 		}
 
 		// Connecting...
 		try
 		{
-			$db = new PDO($this->dsn, $this->username, $this->password, $this->options);
+			return new PDO($this->dsn, $this->username, $this->password, $this->options);
 		}
 		catch (PDOException $e)
 		{
@@ -240,21 +245,6 @@ class CI_DB_pdo_driver extends CI_DB {
 
 			return FALSE;
 		}
-
-		return $db;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Select the database
-	 *
-	 * @return	resource
-	 */
-	public function db_select()
-	{
-		// Not needed for PDO
-		return TRUE;
 	}
 
 	// --------------------------------------------------------------------
@@ -281,46 +271,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	protected function _execute($sql)
 	{
-		$sql = $this->_prep_query($sql);
-
-		$result_id = $this->conn_id->query($sql);
-
-		if (is_object($result_id))
-		{
-			$this->affect_rows = $result_id->rowCount();
-		}
-		else
-		{
-			$this->affect_rows = 0;
-		}
-
-		return $result_id;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Prep the query
-	 *
-	 * If needed, each database adapter can prep the query string
-	 *
-	 * @param	string	an SQL query
-	 * @return	string
-	 */
-	protected function _prep_query($sql)
-	{
-		if ($this->pdodriver === 'pgsql')
-		{
-			// Change the backtick(s) for Postgre
-			$sql = str_replace('`', '"', $sql);
-		}
-		elseif ($this->pdodriver === 'sqlite')
-		{
-			// Change the backtick(s) for SQLite
-			$sql = str_replace('`', '', $sql);
-		}
-
-		return $sql;
+		return $this->conn_id->query($sql);
 	}
 
 	// --------------------------------------------------------------------
@@ -332,13 +283,8 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function trans_begin($test_mode = FALSE)
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -346,7 +292,7 @@ class CI_DB_pdo_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.
-		$this->_trans_failure = (bool) ($test_mode === TRUE);
+		$this->_trans_failure = ($test_mode === TRUE);
 
 		return $this->conn_id->beginTransaction();
 	}
@@ -360,20 +306,13 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function trans_commit()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		$ret = $this->conn->commit();
-
-		return $ret;
+		return $this->conn_id->commit();
 	}
 
 	// --------------------------------------------------------------------
@@ -385,20 +324,13 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function trans_rollback()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		$ret = $this->conn_id->rollBack();
-
-		return $ret;
+		return $this->conn_id->rollBack();
 	}
 
 	// --------------------------------------------------------------------
@@ -422,10 +354,10 @@ class CI_DB_pdo_driver extends CI_DB {
 			return $str;
 		}
 
-		//Escape the string
+		// Escape the string
 		$str = $this->conn_id->quote($str);
 
-		//If there are duplicated quotes, trim them away
+		// If there are duplicated quotes, trim them away
 		if (strpos($str, "'") === 0)
 		{
 			$str = substr($str, 1, -1);
@@ -451,7 +383,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	public function affected_rows()
 	{
-		return $this->affect_rows;
+		return is_object($this->result_id) ? $this->result_id->rowCount() : 0;
 	}
 
 	// --------------------------------------------------------------------
@@ -459,6 +391,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	/**
 	 * Insert ID
 	 *
+	 * @param	string
 	 * @return	int
 	 */
 	public function insert_id($name = NULL)
@@ -476,38 +409,6 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * "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;
-		}
-
-		$sql = $this->_count_string.$this->protect_identifiers('numrows').' FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE);
-		$query = $this->query($sql);
-
-		if ($query->num_rows() == 0)
-		{
-			return 0;
-		}
-
-		$row = $query->row();
-		$this->_reset_select();
-
-		return (int) $row->numrows;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Show table query
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
@@ -517,22 +418,22 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		if ($this->pdodriver == 'pgsql')
+		if ($this->pdodriver === 'pgsql')
 		{
 			// Analog function to show all tables in postgre
 			$sql = "SELECT * FROM information_schema.tables WHERE table_schema = 'public'";
 		}
-		elseif ($this->pdodriver == 'sqlite')
+		elseif ($this->pdodriver === 'sqlite')
 		{
 			// Analog function to show all tables in sqlite
 			$sql = "SELECT name FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%'";
 		}
 		else
 		{
-			$sql = "SHOW TABLES FROM `".$this->database."`";
+			$sql = 'SHOW TABLES FROM '.$this->escape_identifiers($this->database);
 		}
 
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		if ($prefix_limit !== FALSE AND $this->dbprefix !== '')
 		{
 			return FALSE;
 		}
@@ -552,7 +453,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	protected function _list_columns($table = '')
 	{
-		return 'SHOW COLUMNS FROM '.$this->_from_tables($table);
+		return 'SHOW COLUMNS FROM '.$this->escape_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -567,23 +468,23 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	protected function _field_data($table)
 	{
-		if ($this->pdodriver == 'mysql' or $this->pdodriver == 'pgsql')
+		if ($this->pdodriver === 'mysql' or $this->pdodriver === 'pgsql')
 		{
 			// Analog function for mysql and postgre
-			return 'SELECT * FROM '.$this->_from_tables($table).' LIMIT 1';
+			return 'SELECT * FROM '.$this->escape_identifiers($table).' LIMIT 1';
 		}
-		elseif ($this->pdodriver == 'oci')
+		elseif ($this->pdodriver === 'oci')
 		{
 			// Analog function for oci
-			return 'SELECT * FROM '.$this->_from_tables($table).' WHERE ROWNUM <= 1';
+			return 'SELECT * FROM '.$this->escape_identifiers($table).' WHERE ROWNUM <= 1';
 		}
-		elseif ($this->pdodriver == 'sqlite')
+		elseif ($this->pdodriver === 'sqlite')
 		{
 			// Analog function for sqlite
-			return 'PRAGMA table_info('.$this->_from_tables($table).')';
+			return 'PRAGMA table_info('.$this->escape_identifiers($table).')';
 		}
 
-		return 'SELECT TOP 1 FROM '.$this->_from_tables($table);
+		return 'SELECT TOP 1 FROM '.$this->escape_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -618,134 +519,6 @@ class CI_DB_pdo_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Escape the SQL Identifiers
-	 *
-	 * This function escapes column and table names
-	 *
-	 * @param	string
-	 * @return	string
-	 */
-	public function _escape_identifiers($item)
-	{
-		if ($this->_escape_char == '')
-		{
-			return $item;
-		}
-
-		foreach ($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);
-			$str .= $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, $str);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @param	array
-	 * @return	string
-	 */
-	protected function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return (count($tables) == 1) ? '`'.$tables[0].'`' : '('.implode(', ', $tables).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Insert statement
-	 *
-	 * Generates a platform-specific insert string from the supplied data
-	 *
-	 * @param	string	the table name
-	 * @param	array	the insert keys
-	 * @param	array	the insert values
-	 * @return	string
-	 */
-	protected function _insert($table, $keys, $values)
-	{
-		return 'INSERT INTO '.$this->_from_tables($table).' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Insert_batch statement
-	 *
-	 * Generates a platform-specific insert string from the supplied data
-	 *
-	 * @param	string	the table name
-	 * @param	array	the insert keys
-	 * @param	array	the insert values
-	 * @return	string
-	 */
-	protected function _insert_batch($table, $keys, $values)
-	{
-		return 'INSERT INTO '.$this->_from_tables($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) : '';
-
-		$sql  = 'UPDATE '.$this->_from_tables($table).' SET '.implode(', ', $valstr);
-		$sql .= ($where != '' && count($where) >= 1) ? ' WHERE '.implode(' ', $where) : '';
-		$sql .= $orderby.$limit;
-
-		return $sql;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Update_Batch statement
 	 *
 	 * Generates a platform-specific batch update string from the supplied data
@@ -758,7 +531,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	protected function _update_batch($table, $values, $index, $where = NULL)
 	{
 		$ids   = array();
-		$where = ($where != '' && count($where) >=1) ? implode(" ", $where).' AND ' : '';
+		$where = ($where !== '' && count($where) >=1) ? implode(" ", $where).' AND ' : '';
 
 		foreach ($values as $key => $val)
 		{
@@ -766,14 +539,14 @@ class CI_DB_pdo_driver extends CI_DB {
 
 			foreach (array_keys($val) as $field)
 			{
-				if ($field != $index)
+				if ($field !== $index)
 				{
 					$final[$field][] =  'WHEN '.$index.' = '.$val[$index].' THEN '.$val[$field];
 				}
 			}
 		}
 
-		$sql   = 'UPDATE '.$this->_from_tables($table).' SET ';
+		$sql   = 'UPDATE '.$table.' SET ';
 		$cases = '';
 
 		foreach ($final as $k => $v)
@@ -800,49 +573,16 @@ class CI_DB_pdo_driver extends CI_DB {
 	 * Truncate statement
 	 *
 	 * Generates a platform-specific truncate string from the supplied data
-	 * If the database does not support the truncate() command
-	 * This function maps to "DELETE FROM table"
 	 *
-	 * @param	string	the table name
-	 * @return	string
-	 */
-	protected function _truncate($table)
-	{
-		return $this->_delete($table);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Delete statement
-	 *
-	 * Generates a platform-specific delete string from the supplied data
+	 * If the database does not support the truncate() command,
+	 * then this method maps to 'DELETE FROM table'
 	 *
 	 * @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(), $limit = FALSE)
+	protected function _truncate($table)
 	{
-		$conditions = '';
-
-		if (count($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 '.$this->_from_tables($table).$conditions.$limit;
+		return 'DELETE FROM '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -859,7 +599,7 @@ class CI_DB_pdo_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		if ($this->pdodriver == 'cubrid' OR $this->pdodriver == 'sqlite')
+		if ($this->pdodriver === 'cubrid' OR $this->pdodriver === 'sqlite')
 		{
 			$offset = ($offset == 0) ? '' : $offset.', ';
 
@@ -874,19 +614,6 @@ class CI_DB_pdo_driver extends CI_DB {
 		}
 	}
 
-	// --------------------------------------------------------------------
-
-	/**
-	 * Close DB Connection
-	 *
-	 * @param	resource
-	 * @return	void
-	 */
-	protected function _close($conn_id)
-	{
-		$this->conn_id = null;
-	}
-
 }
 
 /* End of file pdo_driver.php */
diff --git a/system/database/drivers/pdo/pdo_forge.php b/system/database/drivers/pdo/pdo_forge.php
index 6bff3542f..02ceb74fe 100644
--- a/system/database/drivers/pdo/pdo_forge.php
+++ b/system/database/drivers/pdo/pdo_forge.php
@@ -34,43 +34,8 @@
  */
 class CI_DB_pdo_forge extends CI_DB_forge {
 
-	/**
-	 * Create database
-	 *
-	 * @param	string	the database name
-	 * @return	bool
-	 */
-	public function _create_database()
-	{
-		// PDO has no "create database" command since it's
-		// designed to connect to an existing database
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Drop database
-	 *
-	 * @param	string	the database name
-	 * @return	bool
-	 */
-	public function _drop_database($name)
-	{
-		// PDO has no "drop database" command since it's
-		// designed to connect to an existing database
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
+	protected $_drop_database	= 'DROP DATABASE %s';
+	protected $_drop_table		= 'DROP TABLE %s';
 
 	/**
 	 * Create Table
@@ -82,7 +47,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 	 * @param	bool	should 'IF NOT EXISTS' be added to the SQL
 	 * @return	bool
 	 */
-	public function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
+	protected function _create_table($table, $fields, $primary_keys, $keys, $if_not_exists)
 	{
 		$sql = 'CREATE TABLE ';
 
@@ -91,56 +56,48 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= '`'.$this->db->_escape_identifiers($table).'` (';
+		$sql .= $this->db->escape_identifiers($table).' (';
 		$current_field_count = 0;
 
-		foreach ($fields as $field=>$attributes)
+		foreach ($fields as $field => $attributes)
 		{
 			// Numeric field names aren't allowed in databases, so if the key is
 			// numeric, we know it was assigned by PHP and the developer manually
 			// entered the field information, so we'll simply add it to the list
 			if (is_numeric($field))
 			{
-				$sql .= "\n\t$attributes";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
-				$numeric    = array('SERIAL', 'INTEGER');
+				$numeric = array('SERIAL', 'INTEGER');
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
-
-				if (array_key_exists('CONSTRAINT', $attributes))
+				if ( ! empty($attributes['CONSTRAINT']))
 				{
 					// Exception for Postgre numeric which not too happy with constraint within those type
-					if ( ! ($this->db->pdodriver == 'pgsql' && in_array($attributes['TYPE'], $numeric)))
+					if ( ! ($this->db->pdodriver === 'pgsql' && in_array($attributes['TYPE'], $numeric)))
 					{
 						$sql .= '('.$attributes['CONSTRAINT'].')';
 					}
 				}
 
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -155,47 +112,22 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tFOREIGN KEY (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Drop Table
-	 *
-	 * @return	bool
-	 */
-	public function _drop_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -215,56 +147,20 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 	 * @param	string	the field after which we should add the new field
 	 * @return	string
 	 */
-	public function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
+	protected function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
 	{
-		$sql = 'ALTER TABLE `'.$this->db->protect_identifiers($table).'` '.$alter_type.' '.$this->db->protect_identifiers($column_name);
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
-		if ($alter_type == 'DROP')
+		if ($alter_type === 'DROP')
 		{
 			return $sql;
 		}
 
-		$sql .= " $column_definition";
-
-		if ($default_value != '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field != '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
-	}
-
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Rename a table
-	 *
-	 * Generates a platform-specific query so that a table can be renamed
-	 *
-	 * @param	string	the old table name
-	 * @param	string	the new table name
-	 * @return	string
-	 */
-	public function _rename_table($table_name, $new_table_name)
-	{
-		return 'ALTER TABLE '.$this->db->protect_identifiers($table_name).' RENAME TO '.$this->db->protect_identifiers($new_table_name);
+		return $sql .' '.$column_definition
+			.($default_value !== '' ? " DEFAULT '".$default_value."'" : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/pdo/pdo_result.php b/system/database/drivers/pdo/pdo_result.php
index 5bbd85d75..0b8937cc5 100644
--- a/system/database/drivers/pdo/pdo_result.php
+++ b/system/database/drivers/pdo/pdo_result.php
@@ -84,20 +84,14 @@ class CI_DB_pdo_result extends CI_DB_result {
 		// Define the output
 		$output = array('assoc', 'object');
 
+		// Initial value
+		$this->result_assoc = array() and $this->result_object = array();
+
 		// Fetch the result
-		foreach ($output as $type)
+		while ($row = $this->_fetch_assoc())
 		{
-			// Define the method and handler
-			$res_method  = '_fetch_'.$type;
-			$res_handler = 'result_'.$type;
-
-			$this->$res_handler = array();
-			$this->_data_seek(0);
-
-			while ($row = $this->$res_method())
-			{
-				$this->{$res_handler}[] = $row;
-			}
+			$this->result_assoc[] = $row;
+			$this->result_object[] = (object) $row;
 		}
 
 		// Save this as buffer and marked the fetch flag
@@ -228,22 +222,6 @@ class CI_DB_pdo_result extends CI_DB_result {
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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	bool
-	 */
-	protected function _data_seek($n = 0)
-	{
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Result - associative array
 	 *
 	 * Returns the result set as an array
@@ -266,7 +244,7 @@ class CI_DB_pdo_result extends CI_DB_result {
 	 */
 	protected function _fetch_object()
 	{
-		return $this->result_id->fetchObject();
+		return $this->result_id->fetch(PDO::FETCH_OBJ);
 	}
 
 }
diff --git a/system/database/drivers/pdo/pdo_utility.php b/system/database/drivers/pdo/pdo_utility.php
index 86c798397..930842118 100644
--- a/system/database/drivers/pdo/pdo_utility.php
+++ b/system/database/drivers/pdo/pdo_utility.php
@@ -34,62 +34,7 @@
  */
 class CI_DB_pdo_utility extends CI_DB_utility {
 
-	/**
-	 * List databases
-	 *
-	 * @return	bool
-	 */
-	public function _list_databases()
-	{
-		// Not sure if PDO lets you list all databases...
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Optimize table query
-	 *
-	 * Generates a platform-specific query so that a table can be optimized
-	 *
-	 * @param	string	the table name
-	 * @return	bool
-	 */
-	public function _optimize_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Repair table query
-	 *
-	 * Generates a platform-specific query so that a table can be repaired
-	 *
-	 * @param	string	the table name
-	 * @return	bool
-	 */
-	public function _repair_table($table)
-	{
-		// Not a supported PDO feature
-		if ($this->db->db_debug)
-		{
-			return $this->db->display_error('db_unsuported_feature');
-		}
-		return FALSE;
-	}
-
-	// --------------------------------------------------------------------
+	protected $_list_databases = FALSE;
 
 	/**
 	 * PDO Export
@@ -97,7 +42,7 @@ class CI_DB_pdo_utility extends CI_DB_utility {
 	 * @param	array	Preferences
 	 * @return	mixed
 	 */
-	public function _backup($params = array())
+	protected function _backup($params = array())
 	{
 		// Currently unsupported
 		return $this->db->display_error('db_unsuported_feature');