11 files changed, 321 insertions, 172 deletions
diff --git a/phpBB/includes/db/db_tools.php b/phpBB/includes/db/db_tools.php
index 6df3aac9ce..2bb016cebd 100644
--- a/phpBB/includes/db/db_tools.php
+++ b/phpBB/includes/db/db_tools.php
@@ -300,7 +300,7 @@ class phpbb_db_tools
 	/**
 	* Constructor. Set DB Object and set {@link $return_statements return_statements}.
 	*
-	* @param phpbb_dbal	$db					DBAL object
+	* @param phpbb_db_driver	$db					Database connection
 	* @param bool		$return_statements	True if only statements should be returned and no SQL being executed
 	*/
 	function phpbb_db_tools(&$db, $return_statements = false)
diff --git a/phpBB/includes/db/dbal.php b/phpBB/includes/db/driver/driver.php
index ef1dd7d14d..8dda94bc2c 100644
--- a/phpBB/includes/db/dbal.php
+++ b/phpBB/includes/db/driver/driver.php
@@ -19,7 +19,7 @@ if (!defined('IN_PHPBB'))
 * Database Abstraction Layer
 * @package dbal
 */
-class dbal
+class phpbb_db_driver
 {
 	var $db_connect_id;
 	var $query_result;
@@ -72,17 +72,17 @@ class dbal
 	/**
 	* Constructor
 	*/
-	function dbal()
+	function __construct()
 	{
 		$this->num_queries = array(
-			'cached'		=> 0,
-			'normal'		=> 0,
-			'total'			=> 0,
+			'cached'	=> 0,
+			'normal'	=> 0,
+			'total'		=> 0,
 		);
 
 		// Fill default sql layer based on the class being called.
 		// This can be changed by the specified layer itself later if needed.
-		$this->sql_layer = substr(get_class($this), 5);
+		$this->sql_layer = substr(get_class($this), strlen('phpbb_db_driver_'));
 
 		// Do not change this please! This variable is used to easy the use of it - and is hardcoded.
 		$this->any_char = chr(0) . '%';
@@ -206,7 +206,7 @@ class dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -256,7 +256,7 @@ class dbal
 				$this->sql_rowseek($rownum, $query_id);
 			}
 
-			if (!is_object($query_id) && $cache->sql_exists($query_id))
+			if ($cache && !is_object($query_id) && $cache->sql_exists($query_id))
 			{
 				return $cache->sql_fetchfield($query_id, $field);
 			}
@@ -822,7 +822,7 @@ class dbal
 	*/
 	function sql_report($mode, $query = '')
 	{
-		global $cache, $starttime, $phpbb_root_path, $user;
+		global $cache, $starttime, $phpbb_root_path, $phpbb_admin_path, $user;
 		global $request;
 
 		if (is_object($request) && !$request->variable('explain', false))
@@ -852,7 +852,7 @@ class dbal
 					<head>
 						<meta charset="utf-8">
 						<title>SQL Report</title>
-						<link href="' . $phpbb_root_path . 'adm/style/admin.css" rel="stylesheet" type="text/css" media="screen" />
+						<link href="' . htmlspecialchars($phpbb_admin_path) . 'style/admin.css" rel="stylesheet" type="text/css" media="screen" />
 					</head>
 					<body id="errorpage">
 					<div id="wrap">
@@ -1042,8 +1042,3 @@ class dbal
 		return $rows_total;
 	}
 }
-
-/**
-* This variable holds the class name to use later
-*/
-$sql_db = (!empty($dbms)) ? 'dbal_' . basename($dbms) : 'dbal';
diff --git a/phpBB/includes/db/firebird.php b/phpBB/includes/db/driver/firebird.php
index 5728eb901c..787c28b812 100644
--- a/phpBB/includes/db/firebird.php
+++ b/phpBB/includes/db/driver/firebird.php
@@ -15,14 +15,12 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * Firebird/Interbase Database Abstraction Layer
 * Minimum Requirement is Firebird 2.1
 * @package dbal
 */
-class dbal_firebird extends dbal
+class phpbb_db_driver_firebird extends phpbb_db_driver
 {
 	var $last_query_text = '';
 	var $service_handle = false;
@@ -156,7 +154,7 @@ class dbal_firebird extends dbal
 			}
 
 			$this->last_query_text = $query;
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -269,10 +267,10 @@ class dbal_firebird extends dbal
 					}
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -332,7 +330,7 @@ class dbal_firebird extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -398,7 +396,7 @@ class dbal_firebird extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
diff --git a/phpBB/includes/db/mssql.php b/phpBB/includes/db/driver/mssql.php
index 1ec8517308..89c2c2351b 100644
--- a/phpBB/includes/db/mssql.php
+++ b/phpBB/includes/db/driver/mssql.php
@@ -15,20 +15,26 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * MSSQL Database Abstraction Layer
 * Minimum Requirement is MSSQL 2000+
 * @package dbal
 */
-class dbal_mssql extends dbal
+class phpbb_db_driver_mssql extends phpbb_db_driver
 {
+	var $connect_error = '';
+
 	/**
 	* Connect to server
 	*/
 	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false, $new_link = false)
 	{
+		if (!function_exists('mssql_connect'))
+		{
+			$this->connect_error = 'mssql_connect function does not exist, is mssql extension installed?';
+			return $this->sql_error('');
+		}
+
 		$this->persistency = $persistency;
 		$this->user = $sqluser;
 		$this->dbname = $database;
@@ -144,7 +150,7 @@ class dbal_mssql extends dbal
 				$this->sql_report('start', $query);
 			}
 
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -159,10 +165,10 @@ class dbal_mssql extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -234,7 +240,7 @@ class dbal_mssql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -271,7 +277,7 @@ class dbal_mssql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -310,7 +316,7 @@ class dbal_mssql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -355,34 +361,44 @@ class dbal_mssql extends dbal
 	*/
 	function _sql_error()
 	{
-		$error = array(
-			'message'	=> @mssql_get_last_message(),
-			'code'		=> ''
-		);
-
-		// Get error code number
-		$result_id = @mssql_query('SELECT @@ERROR as code', $this->db_connect_id);
-		if ($result_id)
+		if (function_exists('mssql_get_last_message'))
 		{
-			$row = @mssql_fetch_assoc($result_id);
-			$error['code'] = $row['code'];
-			@mssql_free_result($result_id);
-		}
+			$error = array(
+				'message'	=> @mssql_get_last_message(),
+				'code'		=> '',
+			);
 
-		// Get full error message if possible
-		$sql = 'SELECT CAST(description as varchar(255)) as message
-			FROM master.dbo.sysmessages
-			WHERE error = ' . $error['code'];
-		$result_id = @mssql_query($sql);
-		
-		if ($result_id)
-		{
-			$row = @mssql_fetch_assoc($result_id);
-			if (!empty($row['message']))
+			// Get error code number
+			$result_id = @mssql_query('SELECT @@ERROR as code', $this->db_connect_id);
+			if ($result_id)
 			{
-				$error['message'] .= '<br />' . $row['message'];
+				$row = @mssql_fetch_assoc($result_id);
+				$error['code'] = $row['code'];
+				@mssql_free_result($result_id);
 			}
-			@mssql_free_result($result_id);
+
+			// Get full error message if possible
+			$sql = 'SELECT CAST(description as varchar(255)) as message
+				FROM master.dbo.sysmessages
+				WHERE error = ' . $error['code'];
+			$result_id = @mssql_query($sql);
+
+			if ($result_id)
+			{
+				$row = @mssql_fetch_assoc($result_id);
+				if (!empty($row['message']))
+				{
+					$error['message'] .= '<br />' . $row['message'];
+				}
+				@mssql_free_result($result_id);
+			}
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
 		}
 
 		return $error;
diff --git a/phpBB/includes/db/mssql_odbc.php b/phpBB/includes/db/driver/mssql_odbc.php
index 7c1ffbc808..f7834443eb 100644
--- a/phpBB/includes/db/mssql_odbc.php
+++ b/phpBB/includes/db/driver/mssql_odbc.php
@@ -15,8 +15,6 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * Unified ODBC functions
 * Unified ODBC functions support any database having ODBC driver, for example Adabas D, IBM DB2, iODBC, Solid, Sybase SQL Anywhere...
@@ -28,9 +26,10 @@ include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
 *
 * @package dbal
 */
-class dbal_mssql_odbc extends dbal
+class phpbb_db_driver_mssql_odbc extends phpbb_db_driver
 {
 	var $last_query_text = '';
+	var $connect_error = '';
 
 	/**
 	* Connect to server
@@ -67,7 +66,24 @@ class dbal_mssql_odbc extends dbal
 			@ini_set('odbc.defaultlrl', $max_size);
 		}
 
-		$this->db_connect_id = ($this->persistency) ? @odbc_pconnect($this->server, $this->user, $sqlpassword) : @odbc_connect($this->server, $this->user, $sqlpassword);
+		if ($this->persistency)
+		{
+			if (!function_exists('odbc_pconnect'))
+			{
+				$this->connect_error = 'odbc_pconnect function does not exist, is odbc extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @odbc_pconnect($this->server, $this->user, $sqlpassword);
+		}
+		else
+		{
+			if (!function_exists('odbc_connect'))
+			{
+				$this->connect_error = 'odbc_connect function does not exist, is odbc extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @odbc_connect($this->server, $this->user, $sqlpassword);
+		}
 
 		return ($this->db_connect_id) ? $this->db_connect_id : $this->sql_error('');
 	}
@@ -163,7 +179,7 @@ class dbal_mssql_odbc extends dbal
 			}
 
 			$this->last_query_text = $query;
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -178,10 +194,10 @@ class dbal_mssql_odbc extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -254,7 +270,7 @@ class dbal_mssql_odbc extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -295,7 +311,7 @@ class dbal_mssql_odbc extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -349,10 +365,22 @@ class dbal_mssql_odbc extends dbal
 	*/
 	function _sql_error()
 	{
-		return array(
-			'message'	=> @odbc_errormsg(),
-			'code'		=> @odbc_error()
-		);
+		if (function_exists('odbc_errormsg'))
+		{
+			$error = array(
+				'message'	=> @odbc_errormsg(),
+				'code'		=> @odbc_error(),
+			);
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
+		}
+
+		return $error;
 	}
 
 	/**
diff --git a/phpBB/includes/db/mssqlnative.php b/phpBB/includes/db/driver/mssqlnative.php
index e9191fae8a..656cbd2437 100644
--- a/phpBB/includes/db/mssqlnative.php
+++ b/phpBB/includes/db/driver/mssqlnative.php
@@ -19,8 +19,6 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
  * Prior to version 1.1 the SQL Server Native PHP driver didn't support sqlsrv_num_rows, or cursor based seeking so we recall all rows into an array
  * and maintain our own cursor index into that array.
@@ -193,21 +191,23 @@ class result_mssqlnative
 /**
 * @package dbal
 */
-class dbal_mssqlnative extends dbal
+class phpbb_db_driver_mssqlnative extends phpbb_db_driver
 {
 	var $m_insert_id = NULL;
 	var $last_query_text = '';
 	var $query_options = array();
+	var $connect_error = '';
 
 	/**
 	* Connect to server
 	*/
 	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false, $new_link = false)
 	{
-		# Test for driver support, to avoid suppressed fatal error
+		// Test for driver support, to avoid suppressed fatal error
 		if (!function_exists('sqlsrv_connect'))
 		{
-			trigger_error('Native MS SQL Server driver for PHP is missing or needs to be updated. Version 1.1 or later is required to install phpBB3. You can download the driver from: http://www.microsoft.com/sqlserver/2005/en/us/PHP-Driver.aspx\n', E_USER_ERROR);
+			$this->connect_error = 'Native MS SQL Server driver for PHP is missing or needs to be updated. Version 1.1 or later is required to install phpBB3. You can download the driver from: http://www.microsoft.com/sqlserver/2005/en/us/PHP-Driver.aspx';
+			return $this->sql_error('');
 		}
 
 		//set up connection variables
@@ -317,7 +317,7 @@ class dbal_mssqlnative extends dbal
 			}
 
 			$this->last_query_text = $query;
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -337,7 +337,7 @@ class dbal_mssqlnative extends dbal
 				if ($cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -521,31 +521,43 @@ class dbal_mssqlnative extends dbal
 	*/
 	function _sql_error()
 	{
-		$errors = @sqlsrv_errors(SQLSRV_ERR_ERRORS);
-		$error_message = '';
-		$code = 0;
-
-		if ($errors != null)
+		if (function_exists('sqlsrv_errors'))
 		{
-			foreach ($errors as $error)
+			$errors = @sqlsrv_errors(SQLSRV_ERR_ERRORS);
+			$error_message = '';
+			$code = 0;
+
+			if ($errors != null)
 			{
-				$error_message .= "SQLSTATE: ".$error[ 'SQLSTATE']."\n";
-				$error_message .= "code: ".$error[ 'code']."\n";
-				$code = $error['code'];
-				$error_message .= "message: ".$error[ 'message']."\n";
+				foreach ($errors as $error)
+				{
+					$error_message .= "SQLSTATE: " . $error[ 'SQLSTATE'] . "\n";
+					$error_message .= "code: " . $error[ 'code'] . "\n";
+					$code = $error['code'];
+					$error_message .= "message: " . $error[ 'message'] . "\n";
+				}
+				$this->last_error_result = $error_message;
+				$error = $this->last_error_result;
 			}
-			$this->last_error_result = $error_message;
-			$error = $this->last_error_result;
+			else
+			{
+				$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			}
+
+			$error = array(
+				'message'	=> $error,
+				'code'		=> $code,
+			);
 		}
 		else
 		{
-			$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
 		}
 
-		return array(
-			'message'	=> $error,
-			'code'		=> $code,
-		);
+		return $error;
 	}
 
 	/**
diff --git a/phpBB/includes/db/mysql.php b/phpBB/includes/db/driver/mysql.php
index f685ab055c..9de7283a42 100644
--- a/phpBB/includes/db/mysql.php
+++ b/phpBB/includes/db/driver/mysql.php
@@ -15,8 +15,6 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * MySQL4 Database Abstraction Layer
 * Compatible with:
@@ -26,9 +24,10 @@ include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
 * MySQL 5.0+
 * @package dbal
 */
-class dbal_mysql extends dbal
+class phpbb_db_driver_mysql extends phpbb_db_driver
 {
 	var $multi_insert = true;
+	var $connect_error = '';
 
 	/**
 	* Connect to server
@@ -43,7 +42,24 @@ class dbal_mysql extends dbal
 
 		$this->sql_layer = 'mysql4';
 
-		$this->db_connect_id = ($this->persistency) ? @mysql_pconnect($this->server, $this->user, $sqlpassword) : @mysql_connect($this->server, $this->user, $sqlpassword, $new_link);
+		if ($this->persistency)
+		{
+			if (!function_exists('mysql_pconnect'))
+			{
+				$this->connect_error = 'mysql_pconnect function does not exist, is mysql extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @mysql_pconnect($this->server, $this->user, $sqlpassword);
+		}
+		else
+		{
+			if (!function_exists('mysql_connect'))
+			{
+				$this->connect_error = 'mysql_connect function does not exist, is mysql extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @mysql_connect($this->server, $this->user, $sqlpassword, $new_link);
+		}
 
 		if ($this->db_connect_id && $this->dbname != '')
 		{
@@ -172,7 +188,7 @@ class dbal_mysql extends dbal
 				$this->sql_report('start', $query);
 			}
 
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -187,10 +203,10 @@ class dbal_mysql extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -249,7 +265,7 @@ class dbal_mysql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -270,7 +286,7 @@ class dbal_mysql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -298,7 +314,7 @@ class dbal_mysql extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -426,18 +442,29 @@ class dbal_mysql extends dbal
 	*/
 	function _sql_error()
 	{
-		if (!$this->db_connect_id)
+		if ($this->db_connect_id)
+		{
+			$error = array(
+				'message'	=> @mysql_error($this->db_connect_id),
+				'code'		=> @mysql_errno($this->db_connect_id),
+			);
+		}
+		else if (function_exists('mysql_error'))
 		{
-			return array(
+			$error = array(
 				'message'	=> @mysql_error(),
-				'code'		=> @mysql_errno()
+				'code'		=> @mysql_errno(),
+			);
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
 			);
 		}
 
-		return array(
-			'message'	=> @mysql_error($this->db_connect_id),
-			'code'		=> @mysql_errno($this->db_connect_id)
-		);
+		return $error;
 	}
 
 	/**
diff --git a/phpBB/includes/db/mysqli.php b/phpBB/includes/db/driver/mysqli.php
index 6d81b8bc3e..7448bf1670 100644
--- a/phpBB/includes/db/mysqli.php
+++ b/phpBB/includes/db/driver/mysqli.php
@@ -15,23 +15,28 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * MySQLi Database Abstraction Layer
 * mysqli-extension has to be compiled with:
 * MySQL 4.1+ or MySQL 5.0+
 * @package dbal
 */
-class dbal_mysqli extends dbal
+class phpbb_db_driver_mysqli extends phpbb_db_driver
 {
 	var $multi_insert = true;
+	var $connect_error = '';
 
 	/**
 	* Connect to server
 	*/
 	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false , $new_link = false)
 	{
+		if (!function_exists('mysqli_connect'))
+		{
+			$this->connect_error = 'mysqli_connect function does not exist, is mysqli extension installed?';
+			return $this->sql_error('');
+		}
+
 		// Mysqli extension supports persistent connection since PHP 5.3.0
 		$this->persistency = (version_compare(PHP_VERSION, '5.3.0', '>=')) ? $persistency : false;
 		$this->user = $sqluser;
@@ -179,7 +184,7 @@ class dbal_mysqli extends dbal
 				$this->sql_report('start', $query);
 			}
 
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -194,9 +199,9 @@ class dbal_mysqli extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 			}
 			else if (defined('DEBUG'))
@@ -251,7 +256,7 @@ class dbal_mysqli extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if (!is_object($query_id) && $cache->sql_exists($query_id))
+		if ($cache && !is_object($query_id) && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -278,7 +283,7 @@ class dbal_mysqli extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if (!is_object($query_id) && $cache->sql_exists($query_id))
+		if ($cache && !is_object($query_id) && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -306,7 +311,7 @@ class dbal_mysqli extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if (!is_object($query_id) && $cache->sql_exists($query_id))
+		if ($cache && !is_object($query_id) && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -423,18 +428,29 @@ class dbal_mysqli extends dbal
 	*/
 	function _sql_error()
 	{
-		if (!$this->db_connect_id)
+		if ($this->db_connect_id)
 		{
-			return array(
+			$error = array(
+				'message'	=> @mysqli_error($this->db_connect_id),
+				'code'		=> @mysqli_errno($this->db_connect_id)
+			);
+		}
+		else if (function_exists('mysqli_connect_error'))
+		{
+			$error = array(
 				'message'	=> @mysqli_connect_error(),
-				'code'		=> @mysqli_connect_errno()
+				'code'		=> @mysqli_connect_errno(),
+			);
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
 			);
 		}
 
-		return array(
-			'message'	=> @mysqli_error($this->db_connect_id),
-			'code'		=> @mysqli_errno($this->db_connect_id)
-		);
+		return $error;
 	}
 
 	/**
diff --git a/phpBB/includes/db/oracle.php b/phpBB/includes/db/driver/oracle.php
index 6d9339b2d8..e21e07055d 100644
--- a/phpBB/includes/db/oracle.php
+++ b/phpBB/includes/db/driver/oracle.php
@@ -15,15 +15,14 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * Oracle Database Abstraction Layer
 * @package dbal
 */
-class dbal_oracle extends dbal
+class phpbb_db_driver_oracle extends phpbb_db_driver
 {
 	var $last_query_text = '';
+	var $connect_error = '';
 
 	/**
 	* Connect to server
@@ -47,7 +46,33 @@ class dbal_oracle extends dbal
 			$connect = $sqlserver . (($port) ? ':' . $port : '') . '/' . $database;
 		}
 
-		$this->db_connect_id = ($new_link) ? @ocinlogon($this->user, $sqlpassword, $connect, 'UTF8') : (($this->persistency) ? @ociplogon($this->user, $sqlpassword, $connect, 'UTF8') : @ocilogon($this->user, $sqlpassword, $connect, 'UTF8'));
+		if ($new_link)
+		{
+			if (!function_exists('ocinlogon'))
+			{
+				$this->connect_error = 'ocinlogon function does not exist, is oci extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @ocinlogon($this->user, $sqlpassword, $connect, 'UTF8');
+		}
+		else if ($this->persistency)
+		{
+			if (!function_exists('ociplogon'))
+			{
+				$this->connect_error = 'ociplogon function does not exist, is oci extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @ociplogon($this->user, $sqlpassword, $connect, 'UTF8');
+		}
+		else
+		{
+			if (!function_exists('ocilogon'))
+			{
+				$this->connect_error = 'ocilogon function does not exist, is oci extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @ocilogon($this->user, $sqlpassword, $connect, 'UTF8');
+		}
 
 		return ($this->db_connect_id) ? $this->db_connect_id : $this->sql_error('');
 	}
@@ -242,7 +267,7 @@ class dbal_oracle extends dbal
 			}
 
 			$this->last_query_text = $query;
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -418,10 +443,10 @@ class dbal_oracle extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -473,7 +498,7 @@ class dbal_oracle extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -525,7 +550,7 @@ class dbal_oracle extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -594,7 +619,7 @@ class dbal_oracle extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -646,17 +671,27 @@ class dbal_oracle extends dbal
 	*/
 	function _sql_error()
 	{
-		$error = @ocierror();
-		$error = (!$error) ? @ocierror($this->query_result) : $error;
-		$error = (!$error) ? @ocierror($this->db_connect_id) : $error;
-
-		if ($error)
+		if (function_exists('ocierror'))
 		{
-			$this->last_error_result = $error;
+			$error = @ocierror();
+			$error = (!$error) ? @ocierror($this->query_result) : $error;
+			$error = (!$error) ? @ocierror($this->db_connect_id) : $error;
+
+			if ($error)
+			{
+				$this->last_error_result = $error;
+			}
+			else
+			{
+				$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			}
 		}
 		else
 		{
-			$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
 		}
 
 		return $error;
diff --git a/phpBB/includes/db/postgres.php b/phpBB/includes/db/driver/postgres.php
index 8dfbfc3b60..14854d179d 100644
--- a/phpBB/includes/db/postgres.php
+++ b/phpBB/includes/db/driver/postgres.php
@@ -15,19 +15,12 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
-if (!class_exists('phpbb_error_collector'))
-{
-	include($phpbb_root_path . 'includes/error_collector.' . $phpEx);
-}
-
 /**
 * PostgreSQL Database Abstraction Layer
 * Minimum Requirement is Version 7.3+
 * @package dbal
 */
-class dbal_postgres extends dbal
+class phpbb_db_driver_postgres extends phpbb_db_driver
 {
 	var $last_query_text = '';
 	var $connect_error = '';
@@ -200,7 +193,7 @@ class dbal_postgres extends dbal
 			}
 
 			$this->last_query_text = $query;
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -215,10 +208,10 @@ class dbal_postgres extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -285,7 +278,7 @@ class dbal_postgres extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -306,7 +299,7 @@ class dbal_postgres extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -355,7 +348,7 @@ class dbal_postgres extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
diff --git a/phpBB/includes/db/sqlite.php b/phpBB/includes/db/driver/sqlite.php
index 5fc89ced18..7188f0daa2 100644
--- a/phpBB/includes/db/sqlite.php
+++ b/phpBB/includes/db/driver/sqlite.php
@@ -15,15 +15,15 @@ if (!defined('IN_PHPBB'))
 	exit;
 }
 
-include_once($phpbb_root_path . 'includes/db/dbal.' . $phpEx);
-
 /**
 * Sqlite Database Abstraction Layer
 * Minimum Requirement: 2.8.2+
 * @package dbal
 */
-class dbal_sqlite extends dbal
+class phpbb_db_driver_sqlite extends phpbb_db_driver
 {
+	var $connect_error = '';
+
 	/**
 	* Connect to server
 	*/
@@ -35,7 +35,24 @@ class dbal_sqlite extends dbal
 		$this->dbname = $database;
 
 		$error = '';
-		$this->db_connect_id = ($this->persistency) ? @sqlite_popen($this->server, 0666, $error) : @sqlite_open($this->server, 0666, $error);
+		if ($this->persistency)
+		{
+			if (!function_exists('sqlite_popen'))
+			{
+				$this->connect_error = 'sqlite_popen function does not exist, is sqlite extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @sqlite_popen($this->server, 0666, $error);
+		}
+		else
+		{
+			if (!function_exists('sqlite_open'))
+			{
+				$this->connect_error = 'sqlite_open function does not exist, is sqlite extension installed?';
+				return $this->sql_error('');
+			}
+			$this->db_connect_id = @sqlite_open($this->server, 0666, $error);
+		}
 
 		if ($this->db_connect_id)
 		{
@@ -117,7 +134,7 @@ class dbal_sqlite extends dbal
 				$this->sql_report('start', $query);
 			}
 
-			$this->query_result = ($cache_ttl) ? $cache->sql_load($query) : false;
+			$this->query_result = ($cache && $cache_ttl) ? $cache->sql_load($query) : false;
 			$this->sql_add_num_queries($this->query_result);
 
 			if ($this->query_result === false)
@@ -132,10 +149,10 @@ class dbal_sqlite extends dbal
 					$this->sql_report('stop', $query);
 				}
 
-				if ($cache_ttl)
+				if ($cache && $cache_ttl)
 				{
 					$this->open_queries[(int) $this->query_result] = $this->query_result;
-					$this->query_result = $cache->sql_save($query, $this->query_result, $cache_ttl);
+					$this->query_result = $cache->sql_save($this, $query, $this->query_result, $cache_ttl);
 				}
 				else if (strpos($query, 'SELECT') === 0 && $this->query_result)
 				{
@@ -193,7 +210,7 @@ class dbal_sqlite extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
@@ -214,7 +231,7 @@ class dbal_sqlite extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_rowseek($rownum, $query_id);
 		}
@@ -242,7 +259,7 @@ class dbal_sqlite extends dbal
 			$query_id = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if ($cache && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}
@@ -280,10 +297,22 @@ class dbal_sqlite extends dbal
 	*/
 	function _sql_error()
 	{
-		return array(
-			'message'	=> @sqlite_error_string(@sqlite_last_error($this->db_connect_id)),
-			'code'		=> @sqlite_last_error($this->db_connect_id)
-		);
+		if (function_exists('sqlite_error_string'))
+		{
+			$error = array(
+				'message'	=> @sqlite_error_string(@sqlite_last_error($this->db_connect_id)),
+				'code'		=> @sqlite_last_error($this->db_connect_id),
+			);
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
+		}
+
+		return $error;
 	}
 
 	/**