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

1 files changed, 306 insertions, 341 deletions

diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 5367f9759..031740851 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -1,76 +1,114 @@
-<?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
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
  *
  * @package		CodeIgniter
- * @author		ExpressionEngine Dev Team
- * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
+ * @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 1.0
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * Postgre 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
  * @subpackage	Drivers
  * @category	Database
- * @author		ExpressionEngine Dev Team
+ * @author		EllisLab Dev Team
  * @link		http://codeigniter.com/user_guide/database/
  */
 class CI_DB_postgre_driver extends CI_DB {
 
-	var $dbdriver = 'postgre';
+	public $dbdriver = 'postgre';
 
-	var $_escape_char = '"';
+	protected $_escape_char = '"';
 
 	// clause and character used for LIKE escape sequences
-	var $_like_escape_str = " ESCAPE '%s' ";
-	var $_like_escape_chr = '!';
+	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.
-	 */
-	var $_count_string = "SELECT COUNT(*) AS ";
-	var $_random_keyword = ' RANDOM()'; // database specific random keyword
+	protected $_random_keyword = ' RANDOM()'; // database specific random keyword
 
 	/**
-	 * Connection String
+	 * Constructor
 	 *
-	 * @access	private
-	 * @return	string
+	 * Creates a DSN string to be used for db_connect() and db_pconnect()
+	 *
+	 * @return	void
 	 */
-	function _connect_string()
+	public function __construct($params)
 	{
-		$components = array(
-								'hostname'	=> 'host',
-								'port'		=> 'port',
-								'database'	=> 'dbname',
-								'username'	=> 'user',
-								'password'	=> 'password'
-							);
-
-		$connect_string = "";
-		foreach ($components as $key => $val)
+		parent::__construct($params);
+
+		if ( ! empty($this->dsn))
+		{
+			return;
+		}
+
+		$this->dsn === '' OR $this->dsn = '';
+
+		if (strpos($this->hostname, '/') !== FALSE)
 		{
-			if (isset($this->$key) && $this->$key != '')
+			// If UNIX sockets are used, we shouldn't set a port
+			$this->port = '';
+		}
+
+		$this->hostname === '' OR $this->dsn = 'host='.$this->hostname.' ';
+
+		if ( ! empty($this->port) && ctype_digit($this->port))
+		{
+			$this->dsn .= 'port='.$this->port.' ';
+		}
+
+		if ($this->username !== '')
+		{
+			$this->dsn .= 'user='.$this->username.' ';
+
+			/* An empty password is valid!
+			 *
+			 * $db['password'] = NULL must be done in order to ignore it.
+			 */
+			$this->password === NULL OR $this->dsn .= "password='".$this->password."' ";
+		}
+
+		$this->database === '' OR $this->dsn .= 'dbname='.$this->database.' ';
+
+		/* We don't have these options as elements in our standard configuration
+		 * array, but they might be set by parse_url() if the configuration was
+		 * provided via string. Example:
+		 *
+		 * postgre://username:password@localhost:5432/database?connect_timeout=5&sslmode=1
+		 */
+		foreach (array('connect_timeout', 'options', 'sslmode', 'service') as $key)
+		{
+			if (isset($this->$key) && is_string($this->key) && $this->key !== '')
 			{
-				$connect_string .= " $val=".$this->$key;
+				$this->dsn .= $key."='".$this->key."' ";
 			}
 		}
-		return trim($connect_string);
+
+		$this->dsn = rtrim($this->dsn);
 	}
 
 	// --------------------------------------------------------------------
@@ -78,12 +116,11 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Non-persistent database connection
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_connect()
+	public function db_connect()
 	{
-		return @pg_connect($this->_connect_string());
+		return @pg_connect($this->dsn);
 	}
 
 	// --------------------------------------------------------------------
@@ -91,12 +128,11 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Persistent database connection
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_pconnect()
+	public function db_pconnect()
 	{
-		return @pg_pconnect($this->_connect_string());
+		return @pg_pconnect($this->dsn);
 	}
 
 	// --------------------------------------------------------------------
@@ -107,10 +143,9 @@ class CI_DB_postgre_driver extends CI_DB {
 	 * Keep / reestablish the db connection if no queries have been
 	 * sent for a length of time exceeding the server's idle timeout
 	 *
-	 * @access	public
 	 * @return	void
 	 */
-	function reconnect()
+	public function reconnect()
 	{
 		if (pg_ping($this->conn_id) === FALSE)
 		{
@@ -121,44 +156,43 @@ class CI_DB_postgre_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Select the database
-	 *
-	 * @access	private called by the base class
-	 * @return	resource
-	 */
-	function db_select()
-	{
-		// Not needed for Postgre so we'll return TRUE
-		return TRUE;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Set client character set
 	 *
-	 * @access	public
-	 * @param	string
 	 * @param	string
-	 * @return	resource
+	 * @return	bool
 	 */
-	function db_set_charset($charset, $collation)
+	protected function _db_set_charset($charset)
 	{
-		// @todo - add support if needed
-		return TRUE;
+		return (pg_set_client_encoding($this->conn_id, $charset) === 0);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Version number query string
+	 * 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();
 	}
 
 	// --------------------------------------------------------------------
@@ -166,49 +200,26 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Execute the query
 	 *
-	 * @access	private called by the base class
 	 * @param	string	an SQL query
 	 * @return	resource
 	 */
-	function _execute($sql)
+	protected function _execute($sql)
 	{
-		$sql = $this->_prep_query($sql);
 		return @pg_query($this->conn_id, $sql);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Prep the query
-	 *
-	 * If needed, each database adapter can prep the query string
-	 *
-	 * @access	private called by execute()
-	 * @param	string	an SQL query
-	 * @return	string
-	 */
-	function _prep_query($sql)
-	{
-		return $sql;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Begin Transaction
 	 *
-	 * @access	public
+	 * @param	bool
 	 * @return	bool
 	 */
-	function trans_begin($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;
 		}
@@ -216,9 +227,9 @@ 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($this->conn_id, "begin");
+		return (bool) @pg_query($this->conn_id, 'BEGIN');
 	}
 
 	// --------------------------------------------------------------------
@@ -226,23 +237,17 @@ 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($this->conn_id, "commit");
+		return (bool) @pg_query($this->conn_id, 'COMMIT');
 	}
 
 	// --------------------------------------------------------------------
@@ -250,23 +255,17 @@ 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($this->conn_id, "rollback");
+		return (bool) @pg_query($this->conn_id, 'ROLLBACK');
 	}
 
 	// --------------------------------------------------------------------
@@ -274,12 +273,11 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Escape String
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	bool	whether or not the string will be used in a LIKE condition
 	 * @return	string
 	 */
-	function escape_str($str, $like = FALSE)
+	public function escape_str($str, $like = FALSE)
 	{
 		if (is_array($str))
 		{
@@ -296,9 +294,9 @@ class CI_DB_postgre_driver extends CI_DB {
 		// 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),
-								$str);
+			return str_replace(array($this->_like_escape_chr, '%', '_'),
+						array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
+						$str);
 		}
 
 		return $str;
@@ -307,86 +305,80 @@ class CI_DB_postgre_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Affected Rows
+	 * "Smart" Escape String
+	 *
+	 * Escapes data based on type
+	 * Sets boolean and null types
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @param	string
+	 * @return	mixed
 	 */
-	function affected_rows()
+	public function escape($str)
 	{
-		return @pg_affected_rows($this->result_id);
+		if (is_bool($str))
+		{
+			return ($str) ? 'TRUE' : 'FALSE';
+		}
+
+		return parent::escape($str);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Insert ID
+	 * Affected Rows
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function insert_id()
+	public function affected_rows()
 	{
-		$v = $this->_version();
-		$v = $v['server'];
-
-		$table	= func_num_args() > 0 ? func_get_arg(0) : NULL;
-		$column	= func_num_args() > 1 ? func_get_arg(1) : NULL;
-
-		if ($table == NULL && $v >= '8.1')
-		{
-			$sql='SELECT LASTVAL() as ins_id';
-		}
-		elseif ($table != NULL && $column != NULL && $v >= '8.0')
-		{
-			$sql = sprintf("SELECT pg_get_serial_sequence('%s','%s') as seq", $table, $column);
-			$query = $this->query($sql);
-			$row = $query->row();
-			$sql = sprintf("SELECT CURRVAL('%s') as ins_id", $row->seq);
-		}
-		elseif ($table != NULL)
-		{
-			// seq_name passed in table parameter
-			$sql = sprintf("SELECT CURRVAL('%s') as ins_id", $table);
-		}
-		else
-		{
-			return pg_last_oid($this->result_id);
-		}
-		$query = $this->query($sql);
-		$row = $query->row();
-		return $row->ins_id;
+		return @pg_affected_rows($this->result_id);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * "Count All" query
-	 *
-	 * Generates a platform-specific query string that counts all records in
-	 * the specified database
+	 * Insert ID
 	 *
-	 * @access	public
-	 * @param	string
 	 * @return	string
 	 */
-	function count_all($table = '')
+	public function insert_id()
 	{
-		if ($table == '')
+		$v = pg_version($this->conn_id);
+		$v = isset($v['server']) ? $v['server'] : 0; // 'server' key is only available since PosgreSQL 7.4
+
+		$table	= (func_num_args() > 0) ? func_get_arg(0) : NULL;
+		$column	= (func_num_args() > 1) ? func_get_arg(1) : NULL;
+
+		if ($table === NULL && $v >= '8.1')
 		{
-			return 0;
+			$sql = 'SELECT LASTVAL() AS ins_id';
 		}
+		elseif ($table !== NULL)
+		{
+			if ($column !== NULL && $v >= '8.0')
+			{
+				$sql = 'SELECT pg_get_serial_sequence(\''.$table."', '".$column."') AS seq";
+				$query = $this->query($sql);
+				$query = $query->row();
+				$seq = $query->seq;
+			}
+			else
+			{
+				// seq_name passed in table parameter
+				$seq = $table;
+			}
 
-		$query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));
-
-		if ($query->num_rows() == 0)
+			$sql = 'SELECT CURRVAL(\''.$seq."') AS ins_id";
+		}
+		else
 		{
-			return 0;
+			return pg_last_oid($this->result_id);
 		}
 
-		$row = $query->row();
-		$this->_reset_select();
-		return (int) $row->numrows;
+		$query = $this->query($sql);
+		$query = $query->row();
+		return (int) $query->ins_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -396,17 +388,18 @@ class CI_DB_postgre_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
 	 *
-	 * @access	private
-	 * @param	boolean
+	 * @param	bool
 	 * @return	string
 	 */
-	function _list_tables($prefix_limit = FALSE)
+	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SELECT table_name FROM information_schema.tables WHERE table_schema = 'public'";
+		$sql = 'SELECT "table_name" FROM "information_schema"."tables" WHERE "table_schema" = \'public\'';
 
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		if ($prefix_limit !== FALSE && $this->dbprefix !== '')
 		{
-			$sql .= " AND table_name LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
+			return $sql.' AND "table_name" LIKE \''
+				.$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
 		}
 
 		return $sql;
@@ -419,13 +412,12 @@ class CI_DB_postgre_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the column names can be fetched
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _list_columns($table = '')
+	protected function _list_columns($table = '')
 	{
-		return "SELECT column_name FROM information_schema.columns WHERE table_name ='".$table."'";
+		return 'SELECT "column_name" FROM "information_schema"."columns" WHERE "table_name" = '.$this->escape($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -435,250 +427,227 @@ class CI_DB_postgre_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query so that the column data can be retrieved
 	 *
-	 * @access	public
 	 * @param	string	the table name
-	 * @return	object
+	 * @return	string
 	 */
-	function _field_data($table)
+	protected function _field_data($table)
 	{
-		return "SELECT * FROM ".$table." LIMIT 1";
+		return 'SELECT * FROM '.$table.' LIMIT 1';
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * 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()
 	{
-		return pg_last_error($this->conn_id);
+		return array('code' => '', 'message' => pg_last_error($this->conn_id));
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * The error message number
+	 * From Tables
+	 *
+	 * This function implicitly groups FROM tables so there is no confusion
+	 * about operator precedence in harmony with SQL standards
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @param	array
+	 * @return	string
 	 */
-	function _error_number()
+	protected function _from_tables($tables)
 	{
-		return '';
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Escape the SQL Identifiers
+	 * Update statement
 	 *
-	 * This function escapes column and table names
+	 * Generates a platform-specific update string from the supplied data
 	 *
-	 * @access	private
-	 * @param	string
+	 * @param	string	the table name
+	 * @param	array	the update data
+	 * @param	array	the where clause
+	 * @param	array	the orderby clause (ignored)
+	 * @param	array	the limit clause (ignored)
+	 * @param	array	the like clause
 	 * @return	string
 	 */
-	function _escape_identifiers($item)
+	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
 	{
-		if ($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, $item).$this->_escape_char;
-		}
-		else
+		foreach ($values as $key => $val)
 		{
-			$str = $this->_escape_char.$item.$this->_escape_char;
+			$valstr[] = $key.' = '.$val;
 		}
 
-		// remove duplicates if the user already included the escape
-		return preg_replace('/['.$this->_escape_char.']+/', $this->_escape_char, $str);
-	}
+		$where = empty($where) ? '' : ' WHERE '.implode(' ', $where);
 
-	// --------------------------------------------------------------------
-
-	/**
-	 * From Tables
-	 *
-	 * This function implicitly groups FROM tables so there is no confusion
-	 * about operator precedence in harmony with SQL standards
-	 *
-	 * @access	public
-	 * @param	type
-	 * @return	type
-	 */
-	function _from_tables($tables)
-	{
-		if ( ! is_array($tables))
+		if ( ! empty($like))
 		{
-			$tables = array($tables);
+			$where .= ($where === '' ? ' WHERE ' : ' AND ').implode(' ', $like);
 		}
 
-		return implode(', ', $tables);
+		return 'UPDATE '.$table.' SET '.implode(', ', $valstr).$where;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Insert statement
+	 * Update_Batch statement
 	 *
-	 * Generates a platform-specific insert string from the supplied data
+	 * Generates a platform-specific batch update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
-	 * @param	array	the insert keys
-	 * @param	array	the insert values
+	 * @param	array	the update data
+	 * @param	array	the where clause
 	 * @return	string
 	 */
-	function _insert($table, $keys, $values)
+	protected function _update_batch($table, $values, $index, $where = NULL)
 	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
-	}
+		$ids = array();
+		foreach ($values as $key => $val)
+		{
+			$ids[] = $val[$index];
 
-	// --------------------------------------------------------------------
+			foreach (array_keys($val) as $field)
+			{
+				if ($field !== $index)
+				{
+					$final[$field][] =  'WHEN '.$val[$index].' THEN '.$val[$field];
+				}
+			}
+		}
 
-	/**
-	 * Insert_batch statement
-	 *
-	 * Generates a platform-specific insert string from the supplied data
-	 *
-	 * @access  public
-	 * @param   string  the table name
-	 * @param   array   the insert keys
-	 * @param   array   the insert values
-	 * @return  string
-	 */
-	function _insert_batch($table, $keys, $values)
-	{
-		return "INSERT INTO ".$table." (".implode(', ', $keys).") VALUES ".implode(', ', $values);
+		$cases = '';
+		foreach ($final as $k => $v)
+		{
+			$cases .= $k.' = (CASE '.$index."\n"
+				.implode("\n", $v)."\n"
+				.'ELSE '.$k.' END), ';
+		}
+
+		return 'UPDATE '.$table.' SET '.substr($cases, 0, -2)
+			.' WHERE '.(($where !== '' && count($where) > 0) ? implode(' ', $where).' AND ' : '')
+			.$index.' IN('.implode(',', $ids).')';
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Update statement
+	 * Delete statement
 	 *
-	 * Generates a platform-specific update string from the supplied data
+	 * Generates a platform-specific delete string from the supplied data
 	 *
-	 * @access	public
 	 * @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
+	 * @param	array	the like clause
+	 * @param	string	the limit clause (ignored)
 	 * @return	string
 	 */
-	function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
 	{
-		foreach ($values as $key => $val)
-		{
-			$valstr[] = $key." = ".$val;
-		}
-
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
-
-		$orderby = (count($orderby) >= 1)?' ORDER BY '.implode(", ", $orderby):'';
+		$conditions = array();
 
-		$sql = "UPDATE ".$table." SET ".implode(', ', $valstr);
+		empty($where) OR $conditions[] = implode(' ', $where);
+		empty($like) OR $conditions[] = implode(' ', $like);
 
-		$sql .= ($where != '' AND count($where) >=1) ? " WHERE ".implode(" ", $where) : '';
-
-		$sql .= $orderby.$limit;
-
-		return $sql;
+		return 'DELETE FROM '.$table.(count($conditions) > 0 ? ' WHERE '.implode(' AND ', $conditions) : '');
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Truncate statement
+	 * Limit string
 	 *
-	 * 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"
+	 * Generates a platform-specific LIMIT clause
 	 *
-	 * @access	public
-	 * @param	string	the table name
+	 * @param	string	the sql query string
+	 * @param	int	the number of rows to limit the query to
+	 * @param	int	the offset value
 	 * @return	string
 	 */
-	function _truncate($table)
+	protected function _limit($sql, $limit, $offset)
 	{
-		return "TRUNCATE ".$table;
+		return $sql.' LIMIT '.$limit.($offset ? ' OFFSET '.$offset : '');
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Delete statement
+	 * Where
 	 *
-	 * Generates a platform-specific delete string from the supplied data
+	 * Called by where() or or_where()
 	 *
-	 * @access	public
-	 * @param	string	the table name
-	 * @param	array	the where clause
-	 * @param	string	the limit clause
-	 * @return	string
+	 * @param	mixed
+	 * @param	mixed
+	 * @param	string
+	 * @param	mixed
+	 * @return	object
 	 */
-	function _delete($table, $where = array(), $like = array(), $limit = FALSE)
+	protected function _where($key, $value = NULL, $type = 'AND ', $escape = NULL)
 	{
-		$conditions = '';
+		if ( ! is_array($key))
+		{
+			$key = array($key => $value);
+		}
+
+		// If the escape value was not set will will base it on the global setting
+		is_bool($escape) OR $escape = $this->_protect_identifiers;
 
-		if (count($where) > 0 OR count($like) > 0)
+		foreach ($key as $k => $v)
 		{
-			$conditions = "\nWHERE ";
-			$conditions .= implode("\n", $this->ar_where);
+			$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0)
+				? $this->_group_get_type('')
+				: $this->_group_get_type($type);
 
-			if (count($where) > 0 && count($like) > 0)
+			if ($escape === TRUE)
 			{
-				$conditions .= " AND ";
+				$k = (($op = $this->_get_operator($k)) !== FALSE)
+					? $this->escape_identifiers(trim(substr($k, 0, strpos($k, $op)))).' '.strstr($k, $op)
+					: $this->escape_identifiers(trim($k));
 			}
-			$conditions .= implode("\n", $like);
-		}
 
-		$limit = ( ! $limit) ? '' : ' LIMIT '.$limit;
+			if (is_null($v) && ! $this->_has_operator($k))
+			{
+				// value appears not to have been set, assign the test to IS NULL
+				$k .= ' IS NULL';
+			}
 
-		return "DELETE FROM ".$table.$conditions.$limit;
-	}
+			if ( ! is_null($v))
+			{
+				if ($escape === TRUE)
+				{
+					$v = ' '.$this->escape($v);
+				}
+				elseif (is_bool($v))
+				{
+					$v = ($v ? ' TRUE' : ' FALSE');
+				}
+
+				if ( ! $this->_has_operator($k))
+				{
+					$k .= ' = ';
+				}
+			}
 
-	// --------------------------------------------------------------------
-	/**
-	 * Limit string
-	 *
-	 * Generates a platform-specific LIMIT clause
-	 *
-	 * @access	public
-	 * @param	string	the sql query string
-	 * @param	integer	the number of rows to limit the query to
-	 * @param	integer	the offset value
-	 * @return	string
-	 */
-	function _limit($sql, $limit, $offset)
-	{
-		$sql .= "LIMIT ".$limit;
+			$this->qb_where[] = $prefix.$k.$v;
+			if ($this->qb_caching === TRUE)
+			{
+				$this->qb_cache_where[] = $prefix.$k.$v;
+				$this->qb_cache_exists[] = 'where';
+			}
 
-		if ($offset > 0)
-		{
-			$sql .= " OFFSET ".$offset;
 		}
 
-		return $sql;
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -686,18 +655,14 @@ class CI_DB_postgre_driver extends CI_DB {
 	/**
 	 * Close DB Connection
 	 *
-	 * @access	public
-	 * @param	resource
 	 * @return	void
 	 */
-	function _close($conn_id)
+	protected function _close()
 	{
-		@pg_close($conn_id);
+		@pg_close($this->conn_id);
 	}
 
-
 }
 
-
 /* End of file postgre_driver.php */
 /* Location: ./system/database/drivers/postgre/postgre_driver.php */
\ No newline at end of file