8 files changed, 1088 insertions, 417 deletions
diff --git a/phpBB/includes/db/firebird.php b/phpBB/includes/db/firebird.php
index b0fb130735..afce881eaf 100644
--- a/phpBB/includes/db/firebird.php
+++ b/phpBB/includes/db/firebird.php
@@ -233,7 +233,7 @@ class sql_db
 
 	function sql_affectedrows()
 	{
-		// hmm, maybe doing something similar as in mssql-odbc.php?
+		// TODO: hmm, maybe doing something similar as in mssql-odbc.php?
 		return ($this->query_result) ? true : false;
 	}
 
@@ -419,6 +419,107 @@ class sql_db
 		return $result;
 	}
 
+	function sql_report($mode, $query = '')
+	{
+		if (empty($_GET['explain']))
+		{
+			return;
+		}
+
+		global $cache, $starttime, $phpbb_root_path;
+		static $curtime, $query_hold, $html_hold;
+		static $sql_report = '';
+		static $cache_num_queries = 0;
+
+		if (!$query && !empty($query_hold))
+		{
+			$query = $query_hold;
+		}
+
+		switch ($mode)
+		{
+			case 'display':
+				if (!empty($cache))
+				{
+					$cache->unload();
+				}
+				$this->sql_close();
+
+				$mtime = explode(' ', microtime());
+				$totaltime = $mtime[0] + $mtime[1] - $starttime;
+
+				echo '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html; charset=iso-8869-1"><meta http-equiv="Content-Style-Type" content="text/css"><link rel="stylesheet" href="' . $phpbb_root_path . 'adm/subSilver.css" type="text/css"><style type="text/css">' . "\n";
+				echo 'th { background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic3.gif\') }' . "\n";
+				echo 'td.cat	{ background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic1.gif\') }' . "\n";
+				echo '</style><title>' . $msg_title . '</title></head><body>';
+				echo '<table width="100%" cellspacing="0" cellpadding="0" border="0"><tr><td><a href="' . htmlspecialchars(preg_replace('/&explain=([^&]*)/', '', $_SERVER['REQUEST_URI'])) . '"><img src="' . $phpbb_root_path . 'adm/images/header_left.jpg" width="200" height="60" alt="phpBB Logo" title="phpBB Logo" border="0"/></a></td><td width="100%" background="' . $phpbb_root_path . 'adm/images/header_bg.jpg" height="60" align="right" nowrap="nowrap"><span class="maintitle">SQL Report</span> &nbsp; &nbsp; &nbsp;</td></tr></table><br clear="all"/><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td height="40" align="center" valign="middle"><b>Page generated in ' . round($totaltime, 4) . " seconds with {$this->num_queries} queries" . (($cache_num_queries) ? " + $cache_num_queries " . (($cache_num_queries == 1) ? 'query' : 'queries') . ' returning data from cache' : '') . '</b></td></tr><tr><td align="center" nowrap="nowrap">Time spent on MySQL queries: <b>' . round($this->sql_time, 5) . 's</b> | Time spent on PHP: <b>' . round($totaltime - $this->sql_time, 5) . 's</b></td></tr></table><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td>';
+				echo $sql_report;
+				echo '</td></tr></table><br /></body></html>';
+				exit;
+				break;
+
+			case 'start':
+				$query_hold = $query;
+				$html_hold = '';
+
+				$curtime = explode(' ', microtime());
+				$curtime = $curtime[0] + $curtime[1];
+				break;
+
+			case 'fromcache':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$result = @ibase_query($this->db_connect_id, $query);
+				while ($void = @ibase_fetch_object($result, IBASE_TEXT))
+				{
+					// Take the time spent on parsing rows into account
+				}
+				$splittime = explode(' ', microtime());
+				$splittime = $splittime[0] + $splittime[1];
+
+				$time_cache = $endtime - $curtime;
+				$time_db = $splittime - $endtime;
+				$color = ($time_db > $time_cache) ? 'green' : 'red';
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query results obtained from the cache</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table><p align="center">';
+
+				$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed [cache]: <b style="color: ' . $color . '">' . sprintf('%.5f', ($time_cache)) . 's</b> | Elapsed [db]: <b>' . sprintf('%.5f', $time_db) . 's</b></p>';
+
+				// Pad the start time to not interfere with page timing
+				$starttime += $time_db;
+
+				@ibase_freeresult($result);
+				$cache_num_queries++;
+				break;
+
+			case 'stop':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query #' . $this->num_queries . '</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table> ' . $html_hold . '<p align="center">';
+
+				if ($this->query_result)
+				{
+					if (preg_match('/^(UPDATE|DELETE|REPLACE)/', $query))
+					{
+						$sql_report .= "Affected rows: <b>" . $this->sql_affectedrows($this->query_result) . '</b> | ';
+					}
+					$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed: <b>' . sprintf('%.5f', $endtime - $curtime) . 's</b>';
+				}
+				else
+				{
+					$error = $this->sql_error();
+					$sql_report .= '<b style="color: red">FAILED</b> - ' . SQL_LAYER . ' Error ' . $error['code'] . ': ' . htmlspecialchars($error['message']);
+				}
+
+				$sql_report .= '</p>';
+
+				$this->sql_time += $endtime - $curtime;
+				break;
+		}
+	}
+
 } // class sql_db
 
 } // if ... define
diff --git a/phpBB/includes/db/mssql-odbc.php b/phpBB/includes/db/mssql-odbc.php
index 5645827472..9fb49837d1 100644
--- a/phpBB/includes/db/mssql-odbc.php
+++ b/phpBB/includes/db/mssql-odbc.php
@@ -387,9 +387,9 @@ class sql_db
 
 		if ($query_id)
 		{
-			if ($row < $this->num_rows[$query_id])
+			if ($rownum < $this->num_rows[$query_id])
 			{
-				$getrow = ($row == -1) ? $this->current_row[$query_id] - 1 : $row;
+				$getrow = ($rownum == -1) ? $this->current_row[$query_id] - 1 : $rownum;
 
 				return $this->result_rowset[$query_id][$getrow][$this->field_names[$query_id][$field]];
 			}
@@ -407,7 +407,7 @@ class sql_db
 
 		if (isset($this->current_row[$query_id]))
 		{
-			$this->current_row[$query_id] = $offset - 1;
+			$this->current_row[$query_id] = $rownum;
 			return true;
 		}
 
@@ -419,36 +419,6 @@ class sql_db
 		return ($this->next_id[$this->db_connect_id]) ? $this->next_id[$this->db_connect_id] : false;
 	}
 
-	function sql_numfields($query_id = false)
-	{
-		if (!$query_id)
-		{
-			$query_id = $this->query_result;
-		}
-
-		return ($query_id) ? sizeof($this->field_names[$query_id]) : false;
-	}
-
-	function sql_fieldname($offset, $query_id = false)
-	{
-		if (!$query_id)
-		{
-			$query_id = $this->query_result;
-		}
-
-		return ($query_id) ? $this->field_names[$query_id][$offset] : false;
-	}
-
-	function sql_fieldtype($offset, $query_id = false)
-	{
-		if (!$query_id)
-		{
-			$query_id = $this->query_result;
-		}
-
-		return ($query_id) ? $this->field_types[$query_id][$offset] : false;
-	}
-
 	function sql_freeresult($query_id = false)
 	{
 		if (!$query_id)
@@ -508,7 +478,7 @@ class sql_db
 			return;
 		}
 
-		global $db, $cache, $starttime, $phpbb_root_path;
+		global $cache, $starttime, $phpbb_root_path;
 		static $curtime, $query_hold, $html_hold;
 		static $sql_report = '';
 		static $cache_num_queries = 0;
@@ -525,7 +495,7 @@ class sql_db
 				{
 					$cache->unload();
 				}
-				$db->sql_close();
+				$this->sql_close();
 
 				$mtime = explode(' ', microtime());
 				$totaltime = $mtime[0] + $mtime[1] - $starttime;
@@ -534,7 +504,7 @@ class sql_db
 				echo 'th { background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic3.gif\') }' . "\n";
 				echo 'td.cat	{ background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic1.gif\') }' . "\n";
 				echo '</style><title>' . $msg_title . '</title></head><body>';
-				echo '<table width="100%" cellspacing="0" cellpadding="0" border="0"><tr><td><a href="' . htmlspecialchars(preg_replace('/&explain=([^&]*)/', '', $_SERVER['REQUEST_URI'])) . '"><img src="' . $phpbb_root_path . 'adm/images/header_left.jpg" width="200" height="60" alt="phpBB Logo" title="phpBB Logo" border="0"/></a></td><td width="100%" background="' . $phpbb_root_path . 'adm/images/header_bg.jpg" height="60" align="right" nowrap="nowrap"><span class="maintitle">SQL Report</span> &nbsp; &nbsp; &nbsp;</td></tr></table><br clear="all"/><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td height="40" align="center" valign="middle"><b>Page generated in ' . round($totaltime, 4) . " seconds with {$this->num_queries} queries" . (($cache_num_queries) ? " + $cache_num_queries " . (($cache_num_queries == 1) ? 'query' : 'queries') . ' returning data from cache' : '') . '</b></td></tr><tr><td align="center" nowrap="nowrap">Time spent on MSSQL queries: <b>' . round($this->sql_time, 5) . 's</b> | Time spent on PHP: <b>' . round($totaltime - $this->sql_time, 5) . 's</b></td></tr></table><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td>';
+				echo '<table width="100%" cellspacing="0" cellpadding="0" border="0"><tr><td><a href="' . htmlspecialchars(preg_replace('/&explain=([^&]*)/', '', $_SERVER['REQUEST_URI'])) . '"><img src="' . $phpbb_root_path . 'adm/images/header_left.jpg" width="200" height="60" alt="phpBB Logo" title="phpBB Logo" border="0"/></a></td><td width="100%" background="' . $phpbb_root_path . 'adm/images/header_bg.jpg" height="60" align="right" nowrap="nowrap"><span class="maintitle">SQL Report</span> &nbsp; &nbsp; &nbsp;</td></tr></table><br clear="all"/><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td height="40" align="center" valign="middle"><b>Page generated in ' . round($totaltime, 4) . " seconds with {$this->num_queries} queries" . (($cache_num_queries) ? " + $cache_num_queries " . (($cache_num_queries == 1) ? 'query' : 'queries') . ' returning data from cache' : '') . '</b></td></tr><tr><td align="center" nowrap="nowrap">Time spent on MySQL queries: <b>' . round($this->sql_time, 5) . 's</b> | Time spent on PHP: <b>' . round($totaltime - $this->sql_time, 5) . 's</b></td></tr></table><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td>';
 				echo $sql_report;
 				echo '</td></tr></table><br /></body></html>';
 				exit;
@@ -544,58 +514,6 @@ class sql_db
 				$query_hold = $query;
 				$html_hold = '';
 
-				$explain_query = $query;
-				if (preg_match('/UPDATE ([a-z0-9_]+).*?WHERE(.*)/s', $query, $m))
-				{
-					$explain_query = 'SELECT * FROM ' . $m[1] . ' WHERE ' . $m[2];
-				}
-				elseif (preg_match('/DELETE FROM ([a-z0-9_]+).*?WHERE(.*)/s', $query, $m))
-				{
-					$explain_query = 'SELECT * FROM ' . $m[1] . ' WHERE ' . $m[2];
-				}
-
-				if (preg_match('/^SELECT/', $explain_query))
-				{
-					$html_table = FALSE;
-
-					@odbc_exec($this->db_connect_id, 'SET SHOWPLAN_ALL ON');
-					
-					if ($result = $this->_odbc_execute_query($explain_query))
-					{
-						while ($row = $this->sql_fetchrow($result))
-						{
-							if (!$html_table && sizeof($row))
-							{
-								$html_table = TRUE;
-								$html_hold .= '<table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0" align="center"><tr>';
-								
-								foreach (array_keys($row) as $val)
-								{
-									$html_hold .= '<th nowrap="nowrap">' . (($val) ? ucwords(str_replace('_', ' ', $val)) : '&nbsp;') . '</th>';
-								}
-								$html_hold .= '</tr>';
-							}
-							$html_hold .= '<tr>';
-
-							$class = 'row1';
-							foreach (array_values($row) as $val)
-							{
-								$class = ($class == 'row1') ? 'row2' : 'row1';
-								$html_hold .= '<td class="' . $class . '">' . (($val) ? $val : '&nbsp;') . '</td>';
-							}
-							$html_hold .= '</tr>';
-						}
-						$this->sql_freeresult($result);
-					}
-
-					@odbc_exec($this->db_connect_id, 'SET SHOWPLAN_ALL OFF');
-
-					if ($html_table)
-					{
-						$html_hold .= '</table>';
-					}
-				}
-
 				$curtime = explode(' ', microtime());
 				$curtime = $curtime[0] + $curtime[1];
 				break;
@@ -605,6 +523,7 @@ class sql_db
 				$endtime = $endtime[0] + $endtime[1];
 
 				$result = $this->_odbc_execute_query($query);
+
 				$splittime = explode(' ', microtime());
 				$splittime = $splittime[0] + $splittime[1];
 
@@ -619,7 +538,7 @@ class sql_db
 				// Pad the start time to not interfere with page timing
 				$starttime += $time_db;
 
-				$this->sql_freeresult($result);
+				@odbc_free_result($result);
 				$cache_num_queries++;
 				break;
 
@@ -640,7 +559,7 @@ class sql_db
 				else
 				{
 					$error = $this->sql_error();
-					$sql_report .= '<b style="color: red">FAILED</b> - MSSQL Error ' . $error['code'] . ': ' . htmlspecialchars($error['message']);
+					$sql_report .= '<b style="color: red">FAILED</b> - ' . SQL_LAYER . ' Error ' . $error['code'] . ': ' . htmlspecialchars($error['message']);
 				}
 
 				$sql_report .= '</p>';
diff --git a/phpBB/includes/db/mssql.php b/phpBB/includes/db/mssql.php
index f68a904ce8..c13f2f2162 100644
--- a/phpBB/includes/db/mssql.php
+++ b/phpBB/includes/db/mssql.php
@@ -11,10 +11,10 @@
 /**
 * @ignore
 */
-if (!defined("SQL_LAYER"))
+if (!defined('SQL_LAYER'))
 {
 
-define("SQL_LAYER","mssql");
+define('SQL_LAYER', 'mssql');
 
 /**
 * @package dbal_mssql
@@ -23,25 +23,19 @@ define("SQL_LAYER","mssql");
 */
 class sql_db
 {
-
 	var $db_connect_id;
-	var $result;
-
-	var $next_id;
-	var $in_transaction = 0;
-
-	var $row = array();
-	var $rowset = array();
-	var $limit_offset;
-	var $query_limit_success;
-
+	var $query_result;
+	var $return_on_error = false;
+	var $transaction = false;
+	var $sql_time = 0;
 	var $num_queries = 0;
+	var $open_queries = array();
 
-	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $persistency = true)
+	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false)
 	{
 		$this->persistency = $persistency;
 		$this->user = $sqluser;
-		$this->server = $sqlserver;
+		$this->server = $sqlserver . (($port) ? ':' . $port : '');
 		$this->dbname = $database;
 
 		$this->db_connect_id = ($this->persistency) ? @mssql_pconnect($this->server, $this->user, $sqlpassword) : @mssql_connect($this->server, $this->user, $sqlpassword);
@@ -58,6 +52,29 @@ class sql_db
 		return ($this->db_connect_id) ? $this->db_connect_id : $this->sql_error('');
 	}
 
+	function sql_close()
+	{
+		if (!$this->db_connect_id)
+		{
+			return false;
+		}
+
+		if ($this->transaction)
+		{
+			@mssql_query('COMMIT', $this->db_connect_id);
+		}
+
+		if (sizeof($this->open_queries))
+		{
+			foreach ($this->open_queries as $i_query_id => $query_id)
+			{
+				@mssql_free_result($query_id);
+			}
+		}
+
+		return @mssql_close($this->db_connect_id);
+	}
+
 	function sql_return_on_error($fail = false)
 	{
 		$this->return_on_error = $fail;
@@ -68,342 +85,332 @@ class sql_db
 		return $this->num_queries;
 	}
 
-	//
-	// Other base methods
-	//
-	function sql_close()
+	function sql_transaction($status = 'begin')
 	{
-		if ($this->db_connect_id)
+		switch ($status)
 		{
-			//
-			// Commit any remaining transactions
-			//
-			if ($this->in_transaction)
-			{
-				@mssql_query("COMMIT", $this->db_connect_id);
-			}
+			case 'begin':
+				$result = @mssql_query('BEGIN TRANSACTION', $this->db_connect_id);
+				$this->transaction = true;
+				break;
 
-			return @mssql_close($this->db_connect_id);
-		}
-		else
-		{
-			return false;
+			case 'commit':
+				$result = @mssql_query('commit', $this->db_connect_id);
+				$this->transaction = false;
+
+				if (!$result)
+				{
+					@mssql_query('ROLLBACK', $this->db_connect_id);
+				}
+				break;
+
+			case 'rollback':
+				$result = @mssql_query('ROLLBACK', $this->db_connect_id);
+				$this->transaction = false;
+				break;
+
+			default:
+				$result = true;
 		}
-	}
 
+		return $result;
+	}
 
-	//
-	// Query method
-	//
-	function sql_query($query = "", $transaction = FALSE)
+	// Base query method
+	function sql_query($query = '', $cache_ttl = 0)
 	{
-		//
-		// Remove any pre-existing queries
-		//
-		unset($this->result);
-		unset($this->row);
-
-		if ($query != "")
+		if ($query != '')
 		{
-			$this->num_queries++;
+			global $cache;
 
-			if ($transaction == BEGIN_TRANSACTION && !$this->in_transaction)
+			// EXPLAIN only in extra debug mode
+			if (defined('DEBUG_EXTRA'))
 			{
-				if (!mssql_query("BEGIN TRANSACTION", $this->db_connect_id))
-				{
-					return false;
-				}
-				$this->in_transaction = TRUE;
+				$this->sql_report('start', $query);
 			}
 
-			//
-			// Does query contain any LIMIT code? If so pull out relevant start and num_results
-			// This isn't terribly easy with MSSQL, whatever you do will potentially impact
-			// performance compared to an 'in-built' limit
-			//
-			// Another issue is the 'lack' of a returned true value when a query is valid but has
-			// no result set (as with all the other DB interfaces). It seems though that it's
-			// 'fair' to say that if a query returns a false result (ie. no resource id) then the
-			// SQL was valid but had no result set. If the query returns nothing but the rowcount
-			// returns something then there's a problem. This may well be a false assumption though
-			// ... needs checking under Windows itself.
-			//
-			if (preg_match("/^SELECT(.*?)(LIMIT ([0-9]+)[, ]*([0-9]+)*)?$/s", $query, $limits))
-			{
-				$query = $limits[1];
+			$this->query_result = ($cache_ttl && method_exists($cache, 'sql_load')) ? $cache->sql_load($query) : false;
 
-				if (!empty($limits[2]))
+			if (!$this->query_result)
+			{
+				$this->num_queries++;
+				
+				if (($this->query_result = @mssql_query($query, $this->db_connect_id)) === false)
 				{
-					$row_offset = ($limits[4]) ? $limits[3] : "";
-					$num_rows = ($limits[4]) ? $limits[4] : $limits[3];
-
-					$query = "TOP " . ($row_offset + $num_rows) . $query;
+					$this->sql_error($query);
 				}
 
-				$this->result = mssql_query("SELECT $query", $this->db_connect_id); 
-
-				if ($this->result)
+				if (defined('DEBUG_EXTRA'))
 				{
-					$this->limit_offset[$this->result] = (!empty($row_offset)) ? $row_offset : 0;
+					$this->sql_report('stop', $query);
+				}
 
-					if ($row_offset > 0)
-					{
-						mssql_data_seek($this->result, $row_offset);
-					}
+				if ($cache_ttl && method_exists($cache, 'sql_save'))
+				{
+					$this->open_queries[(int) $this->query_result] = $this->query_result;
+					$cache->sql_save($query, $this->query_result, $cache_ttl);
+					// sql_freeresult called within sql_save()
 				}
-			}
-			else if (eregi("^INSERT ", $query))
-			{
-				if (mssql_query($query, $this->db_connect_id))
+				else if (strpos($query, 'SELECT') !== false && $this->query_result)
 				{
-					$this->result = time() + microtime();
-
-					$result_id = mssql_query("SELECT @@IDENTITY AS id, @@ROWCOUNT as affected", $this->db_connect_id);
-					if ($result_id)
-					{
-						if ($row = mssql_fetch_array($result_id))
-						{
-							$this->next_id[$this->db_connect_id] = $row['id'];	
-							$this->affected_rows[$this->db_connect_id] = $row['affected'];
-						}
-					}
+					$this->open_queries[(int) $this->query_result] = $this->query_result;
 				}
 			}
-			else
+			else if (defined('DEBUG_EXTRA'))
 			{
-				if (mssql_query($query, $this->db_connect_id))
-				{
-					$this->result = time() + microtime();
-
-					$result_id = mssql_query("SELECT @@ROWCOUNT as affected", $this->db_connect_id);
-					if ($result_id)
-					{
-						if ($row = mssql_fetch_array($result_id))
-						{
-							$this->affected_rows[$this->db_connect_id] = $row['affected'];
-						}
-					}
-				}
+				$this->sql_report('fromcache', $query);
 			}
+		}
+		else
+		{
+			return false;
+		}
 
-			if (!$this->result)
-			{
-				if ($this->in_transaction)
-				{
-					mssql_query("ROLLBACK", $this->db_connect_id);
-					$this->in_transaction = FALSE;
-				}
+		return ($this->query_result) ? $this->query_result : false;
+	}
 
-				return false;
+	function sql_query_limit($query, $total, $offset = 0, $cache_ttl = 0) 
+	{ 
+		if ($query != '') 
+		{
+			$this->query_result = false; 
+
+			// if $total is set to 0 we do not want to limit the number of rows
+			if ($total == 0)
+			{
+				$total = -1;
 			}
 
-			if ($transaction == END_TRANSACTION && $this->in_transaction)
+			$row_offset = ($total) ? $offset : '';
+			$num_rows = ($total) ? $total : $offset;
+
+			$query = 'SELECT TOP ' . ($row_offset + $num_rows) . ' ' . substr($query, 6);
+
+			return $this->sql_query($query, $cache_ttl); 
+		} 
+		else 
+		{ 
+			return false; 
+		} 
+	}
+
+	// Idea for this from Ikonboard
+	function sql_build_array($query, $assoc_ary = false)
+	{
+		if (!is_array($assoc_ary))
+		{
+			return false;
+		}
+
+		$fields = array();
+		$values = array();
+		if ($query == 'INSERT')
+		{
+			foreach ($assoc_ary as $key => $var)
 			{
-				$this->in_transaction = FALSE;
+				$fields[] = $key;
 
-				if (!@mssql_query("COMMIT", $this->db_connect_id))
+				if (is_null($var))
+				{
+					$values[] = 'NULL';
+				}
+				elseif (is_string($var))
 				{
-					@mssql_query("ROLLBACK", $this->db_connect_id);
-					return false;
+					$values[] = "'" . $this->sql_escape($var) . "'";
+				}
+				else
+				{
+					$values[] = (is_bool($var)) ? intval($var) : $var;
 				}
 			}
 
-			return $this->result;
+			$query = ' (' . implode(', ', $fields) . ') VALUES (' . implode(', ', $values) . ')';
 		}
-		else
+		else if ($query == 'UPDATE' || $query == 'SELECT')
 		{
-			if ($transaction == END_TRANSACTION && $this->in_transaction)
+			$values = array();
+			foreach ($assoc_ary as $key => $var)
 			{
-				$this->in_transaction = FALSE;
-
-				if (!@mssql_query("COMMIT", $this->db_connect_id))
+				if (is_null($var))
+				{
+					$values[] = "$key = NULL";
+				}
+				elseif (is_string($var))
+				{
+					$values[] = "$key = '" . $this->sql_escape($var) . "'";
+				}
+				else
 				{
-					@mssql_query("ROLLBACK", $this->db_connect_id);
-					return false;
+					$values[] = (is_bool($var)) ? "$key = " . intval($var) : "$key = $var";
 				}
 			}
-
-			return true;
+			$query = implode(($query == 'UPDATE') ? ', ' : ' AND ', $values);
 		}
+
+		return $query;
 	}
 
-	//
 	// Other query methods
 	//
-	function sql_numrows($query_id = 0)
+	// NOTE :: Want to remove _ALL_ reliance on sql_numrows from core code ...
+	//         don't want this here by a middle Milestone
+	function sql_numrows($query_id = false)
 	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
-		if ($query_id)
-		{
-			return (!empty($this->limit_offset[$query_id])) ? mssql_num_rows($query_id) - $this->limit_offset[$query_id] : @mssql_num_rows($query_id);
-		}
-		else
-		{
-			return false;
-		}
+//		return (isset($this->limit_offset[$query_id])) ? @mssql_num_rows($query_id) - $this->limit_offset[$query_id] : @mssql_num_rows($query_id);
+		return ($query_id) ? @mssql_num_rows($query_id) : false;
 	}
 
-	function sql_numfields($query_id = 0)
+	function sql_affectedrows()
 	{
-		if (!$query_id)
-		{
-			$query_id = $this->result;
-		}
-
-		return ($query_id) ? mssql_num_fields($query_id) : false;
+		return ($this->db_connect_id) ? @mssql_rows_affected($this->db_connect_id) : false;
 	}
 
-	function sql_fieldname($offset, $query_id = 0)
+	function sql_fetchrow($query_id = false)
 	{
-		if (!$query_id)
-		{
-			$query_id = $this->result;
-		}
+		global $cache;
 
-		return ($query_id) ? mssql_field_name($query_id, $offset) : false;
-	}
-
-	function sql_fieldtype($offset, $query_id = 0)
-	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
-		return ($query_id) ? mssql_field_type($query_id, $offset) : false;
-	}
-
-	function sql_fetchrow($query_id = 0)
-	{
-		if (!$query_id)
+		if (isset($cache->sql_rowset[$query_id]))
 		{
-			$query_id = $this->result;
+			return $cache->sql_fetchrow($query_id);
 		}
 
-		if ($query_id)
+		$row = @mssql_fetch_array($query_id, MSSQL_ASSOC);
+		
+		if ($row)
 		{
-			empty($row);
-
-			$row = mssql_fetch_array($query_id);
-
 			foreach ($row as $key => $value)
 			{
-				$row[$key] = stripslashes($value);
+				$row[$key] = ($value === ' ') ? trim($value) : $value;
 			}
-
-			return $row;
-		}
-		else
-		{
-			return false;
 		}
+
+		return $row;
 	}
 
-	function sql_fetchrowset($query_id = 0)
+	function sql_fetchrowset($query_id = false)
 	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
 		if ($query_id)
 		{
-			$i = 0;
-			$rowset = array();
+			unset($this->rowset[$query_id]);
+			unset($this->row[$query_id]);
 
-			while ($row = mssql_fetch_array($query_id))
+			$result = array();
+			while ($this->rowset[$query_id] = $this->sql_fetchrow($query_id))
 			{
-				foreach ($row as $key => $value)
-				{
-					$rowset[$i][$key] = stripslashes($value);
-				}
-				$i++;
+				$result[] = $this->rowset[$query_id];
 			}
-
-			return $rowset;
-		}
-		else
-		{
-			return false;
+			return $result;
 		}
+
+		return false;
 	}
 
-	function sql_fetchfield($field, $row = -1, $query_id)
+	function sql_fetchfield($field, $rownum = -1, $query_id = false)
 	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
 		if ($query_id)
 		{
-			if ($row != -1)
+			if ($rownum > -1)
 			{
-				if ($this->limit_offset[$query_id] > 0)
-				{
-					$result = (!empty($this->limit_offset[$query_id])) ? mssql_result($this->result, ($this->limit_offset[$query_id] + $row), $field) : false;
-				}
-				else
-				{
-					$result = mssql_result($this->result, $row, $field);
-				}
+//				(!empty($this->limit_offset[$query_id])) ? @mssql_data_seek($query_id, ($this->limit_offset[$query_id] + $rownum)) : @mssql_data_seek($query_id, $rownum);
+				@mssql_data_seek($query_id, $rownum);
+				$row = @mssql_fetch_array($query_id, MSSQL_ASSOC);
+				$result = isset($row[$field]) ? $row[$field] : false;
 			}
 			else
 			{
-				if (empty($this->row[$query_id]))
+				if (empty($this->row[$query_id]) && empty($this->rowset[$query_id]))
 				{
-					$this->row[$query_id] = mssql_fetch_array($query_id);
-					$result = stripslashes($this->row[$query_id][$field]);
+					if ($this->sql_fetchrow($query_id))
+					{
+						$result = $this->row[$query_id][$field];
+					}
+				}
+				else
+				{
+					if ($this->rowset[$query_id])
+					{
+						$result = $this->rowset[$query_id][$field];
+					}
+					elseif ($this->row[$query_id])
+					{
+						$result = $this->row[$query_id][$field];
+					}
 				}
 			}
 
 			return $result;
 		}
-		else
-		{
-			return false;
-		}
+
+		return false;
 	}
 
-	function sql_rowseek($rownum, $query_id = 0)
+	function sql_rowseek($rownum, $query_id = false)
 	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
-		if ($query_id)
+		if (isset($this->current_row[$query_id]))
 		{
-			return (!empty($this->limit_offset[$query_id])) ? mssql_data_seek($query_id, ($this->limit_offset[$query_id] + $rownum)) : mssql_data_seek($query_id, $rownum);
-		}
-		else
-		{
-			return false;
+//			(!empty($this->limit_offset[$query_id])) ? @mssql_data_seek($query_id, ($this->limit_offset[$query_id] + $rownum)) : @mssql_data_seek($query_id, $rownum);
+			@mssql_data_seek($query_id, $rownum);
+			return true;
 		}
+
+		return false;
 	}
 
 	function sql_nextid()
 	{
-		return ($this->next_id[$this->db_connect_id]) ? $this->next_id[$this->db_connect_id] : false;
-	}
+		$result_id = @mssql_query('SELECT @@IDENTITY', $this->db_connect_id);
+		if ($result_id)
+		{
+			if (@mssql_fetch_array($result_id, MSSQL_ASSOC))
+			{
+				return @mssql_result($result_id, 1);	
+			}
+		}
 
-	function sql_affectedrows()
-	{
-		return ($this->affected_rows[$this->db_connect_id]) ? $this->affected_rows[$this->db_connect_id] : false;
+		return false;
 	}
 
-	function sql_freeresult($query_id = 0)
+	function sql_freeresult($query_id = false)
 	{
 		if (!$query_id)
 		{
-			$query_id = $this->result;
+			$query_id = $this->query_result;
 		}
 
-		return ($query_id) ? mssql_free_result($query_id) : false;
+		if (isset($this->open_queries[$query_id]))
+		{
+			unset($this->open_queries[$query_id]);
+			unset($this->result_rowset[$query_id]);
+
+			return @mssql_free_result($query_id);
+		}
+
+		return false;
 	}
 
 	function sql_escape($msg)
@@ -415,8 +422,8 @@ class sql_db
 	{
 		if (!$this->return_on_error)
 		{
-			$this_page = (!empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
-			$this_page .= '&' . ((!empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : $_ENV['QUERY_STRING']);
+			$this_page = (isset($_SERVER['PHP_SELF']) && !empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
+			$this_page .= '&' . ((isset($_SERVER['QUERY_STRING']) && !empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : (isset($_ENV['QUERY_STRING']) ? $_ENV['QUERY_STRING'] : ''));
 
 			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @mssql_get_last_message() . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
 
@@ -429,13 +436,114 @@ class sql_db
 		}
 
 		$result = array(
-			'message'	=> @mssql_get_last_message(),
+			'message'	=> @mssql_get_last_message($this->db_connect_id),
 			'code'		=> ''
 		);
 
 		return $result;
 	}
 
+	function sql_report($mode, $query = '')
+	{
+		if (empty($_GET['explain']))
+		{
+			return;
+		}
+
+		global $cache, $starttime, $phpbb_root_path;
+		static $curtime, $query_hold, $html_hold;
+		static $sql_report = '';
+		static $cache_num_queries = 0;
+
+		if (!$query && !empty($query_hold))
+		{
+			$query = $query_hold;
+		}
+
+		switch ($mode)
+		{
+			case 'display':
+				if (!empty($cache))
+				{
+					$cache->unload();
+				}
+				$this->sql_close();
+
+				$mtime = explode(' ', microtime());
+				$totaltime = $mtime[0] + $mtime[1] - $starttime;
+
+				echo '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html; charset=iso-8869-1"><meta http-equiv="Content-Style-Type" content="text/css"><link rel="stylesheet" href="' . $phpbb_root_path . 'adm/subSilver.css" type="text/css"><style type="text/css">' . "\n";
+				echo 'th { background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic3.gif\') }' . "\n";
+				echo 'td.cat	{ background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic1.gif\') }' . "\n";
+				echo '</style><title>' . $msg_title . '</title></head><body>';
+				echo '<table width="100%" cellspacing="0" cellpadding="0" border="0"><tr><td><a href="' . htmlspecialchars(preg_replace('/&explain=([^&]*)/', '', $_SERVER['REQUEST_URI'])) . '"><img src="' . $phpbb_root_path . 'adm/images/header_left.jpg" width="200" height="60" alt="phpBB Logo" title="phpBB Logo" border="0"/></a></td><td width="100%" background="' . $phpbb_root_path . 'adm/images/header_bg.jpg" height="60" align="right" nowrap="nowrap"><span class="maintitle">SQL Report</span> &nbsp; &nbsp; &nbsp;</td></tr></table><br clear="all"/><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td height="40" align="center" valign="middle"><b>Page generated in ' . round($totaltime, 4) . " seconds with {$this->num_queries} queries" . (($cache_num_queries) ? " + $cache_num_queries " . (($cache_num_queries == 1) ? 'query' : 'queries') . ' returning data from cache' : '') . '</b></td></tr><tr><td align="center" nowrap="nowrap">Time spent on MySQL queries: <b>' . round($this->sql_time, 5) . 's</b> | Time spent on PHP: <b>' . round($totaltime - $this->sql_time, 5) . 's</b></td></tr></table><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td>';
+				echo $sql_report;
+				echo '</td></tr></table><br /></body></html>';
+				exit;
+				break;
+
+			case 'start':
+				$query_hold = $query;
+				$html_hold = '';
+
+				$curtime = explode(' ', microtime());
+				$curtime = $curtime[0] + $curtime[1];
+				break;
+
+			case 'fromcache':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$result = @mssql_query($query, $this->db_connect_id);
+				while ($void = @mssql_fetch_array($result, MSSQL_ASSOC))
+				{
+					// Take the time spent on parsing rows into account
+				}
+				$splittime = explode(' ', microtime());
+				$splittime = $splittime[0] + $splittime[1];
+
+				$time_cache = $endtime - $curtime;
+				$time_db = $splittime - $endtime;
+				$color = ($time_db > $time_cache) ? 'green' : 'red';
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query results obtained from the cache</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table><p align="center">';
+
+				$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed [cache]: <b style="color: ' . $color . '">' . sprintf('%.5f', ($time_cache)) . 's</b> | Elapsed [db]: <b>' . sprintf('%.5f', $time_db) . 's</b></p>';
+
+				// Pad the start time to not interfere with page timing
+				$starttime += $time_db;
+
+				@mssql_free_result($result);
+				$cache_num_queries++;
+				break;
+
+			case 'stop':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query #' . $this->num_queries . '</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table> ' . $html_hold . '<p align="center">';
+
+				if ($this->query_result)
+				{
+					if (preg_match('/^(UPDATE|DELETE|REPLACE)/', $query))
+					{
+						$sql_report .= "Affected rows: <b>" . $this->sql_affectedrows($this->query_result) . '</b> | ';
+					}
+					$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed: <b>' . sprintf('%.5f', $endtime - $curtime) . 's</b>';
+				}
+				else
+				{
+					$error = $this->sql_error();
+					$sql_report .= '<b style="color: red">FAILED</b> - ' . SQL_LAYER . ' Error ' . $error['code'] . ': ' . htmlspecialchars($error['message']);
+				}
+
+				$sql_report .= '</p>';
+
+				$this->sql_time += $endtime - $curtime;
+				break;
+		}
+	}
+
 } // class sql_db
 
 } // if ... define
diff --git a/phpBB/includes/db/mysql4.php b/phpBB/includes/db/mysql4.php
index 041e148c11..bf323ec54e 100644
--- a/phpBB/includes/db/mysql4.php
+++ b/phpBB/includes/db/mysql4.php
@@ -19,9 +19,7 @@ define('SQL_LAYER', 'mysql4');
 /**
 * @package dbal_mysql4
 * MySQL4 Database Abstraction Layer
-* Minimum Requirement is MySQL 4.1+
-*
-* @todo Rename mysql4.php to mysqli.php to reflect the used module
+* Minimum Requirement is 4.0+/4.1+
 */
 class sql_db
 {
@@ -33,8 +31,6 @@ class sql_db
 	var $num_queries = 0;
 	var $open_queries = array();
 
-	var $indexed = 0;
-
 	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false)
 	{
 		$this->persistency = $persistency;
@@ -42,11 +38,11 @@ class sql_db
 		$this->server = $sqlserver . (($port) ? ':' . $port : '');
 		$this->dbname = $database;
 
-		$this->db_connect_id = ($this->persistency) ? @mysqli_pconnect($this->server, $this->user, $sqlpassword) : @mysqli_connect($this->server, $this->user, $sqlpassword);
+		$this->db_connect_id = ($this->persistency) ? @mysql_pconnect($this->server, $this->user, $sqlpassword) : @mysql_connect($this->server, $this->user, $sqlpassword);
 
 		if ($this->db_connect_id && $this->dbname != '')
 		{
-			if (@mysqli_select_db($this->db_connect_id, $this->dbname))
+			if (@mysql_select_db($this->dbname))
 			{
 				return $this->db_connect_id;
 			}
@@ -65,12 +61,15 @@ class sql_db
 			return false;
 		}
 
-		if ($this->transaction)
+		if (sizeof($this->open_queries))
 		{
-			@mysqli_commit($this->db_connect_id);
+			foreach ($this->open_queries as $i_query_id => $query_id)
+			{
+				@mysql_free_result($query_id);
+			}
 		}
 
-		return @mysqli_close($this->db_connect_id);
+		return @mysql_close($this->db_connect_id);
 	}
 
 	function sql_return_on_error($fail = false)
@@ -88,25 +87,22 @@ class sql_db
 		switch ($status)
 		{
 			case 'begin':
-				$result = @mysqli_autocommit($this->db_connect_id, false);
+				$result = @mysql_query('BEGIN', $this->db_connect_id);
 				$this->transaction = true;
 				break;
 
 			case 'commit':
-				$result = @mysqli_commit($this->db_connect_id);
-				@mysqli_autocommit($this->db_connect_id, true);
+				$result = @mysql_query('COMMIT', $this->db_connect_id);
 				$this->transaction = false;
-
+				
 				if (!$result)
 				{
-					@mysqli_rollback($this->db_connect_id);
-					@mysqli_autocommit($this->db_connect_id, true);
+					@mysql_query('ROLLBACK', $this->db_connect_id);
 				}
 				break;
 
 			case 'rollback':
-				$result = @mysqli_rollback($this->db_connect_id);
-				@mysqli_autocommit($this->db_connect_id, true);
+				$result = @mysql_query('ROLLBACK', $this->db_connect_id);
 				$this->transaction = false;
 				break;
 
@@ -131,21 +127,16 @@ class sql_db
 			}
 
 			$this->query_result = ($cache_ttl && method_exists($cache, 'sql_load')) ? $cache->sql_load($query) : false;
-			
+
 			if (!$this->query_result)
 			{
 				$this->num_queries++;
 
-				if (($this->query_result = @mysqli_query($this->db_connect_id, $query)) === false)
+				if (($this->query_result = @mysql_query($query, $this->db_connect_id)) === false)
 				{
 					$this->sql_error($query);
 				}
 
-				if (is_object($this->query_result))
-				{
-					$this->query_result->cur_index = $this->indexed++;
-				}
-
 				if (defined('DEBUG_EXTRA'))
 				{
 					$this->sql_report('stop', $query);
@@ -153,7 +144,13 @@ class sql_db
 
 				if ($cache_ttl && method_exists($cache, 'sql_save'))
 				{
+					$this->open_queries[(int) $this->query_result] = $this->query_result;
 					$cache->sql_save($query, $this->query_result, $cache_ttl);
+					// mysql_free_result called within sql_save()
+				}
+				else if (strpos($query, 'SELECT') !== false && $this->query_result)
+				{
+					$this->open_queries[(int) $this->query_result] = $this->query_result;
 				}
 			}
 			else if (defined('DEBUG_EXTRA'))
@@ -258,12 +255,12 @@ class sql_db
 			$query_id = $this->query_result;
 		}
 
-		return ($query_id) ? @mysqli_num_rows($query_id) : false;
+		return ($query_id) ? @mysql_num_rows($query_id) : false;
 	}
 
 	function sql_affectedrows()
 	{
-		return ($this->db_connect_id) ? @mysqli_affected_rows($this->db_connect_id) : false;
+		return ($this->db_connect_id) ? @mysql_affected_rows($this->db_connect_id) : false;
 	}
 
 	function sql_fetchrow($query_id = false)
@@ -275,12 +272,12 @@ class sql_db
 			$query_id = $this->query_result;
 		}
 
-		if (!is_object($query_id) && isset($cache->sql_rowset[$query_id]))
+		if (isset($cache->sql_rowset[$query_id]))
 		{
 			return $cache->sql_fetchrow($query_id);
 		}
 
-		return ($query_id) ? @mysqli_fetch_assoc($query_id) : false;
+		return ($query_id) ? @mysql_fetch_assoc($query_id) : false;
 	}
 
 	function sql_fetchrowset($query_id = false)
@@ -292,19 +289,17 @@ class sql_db
 
 		if ($query_id)
 		{
-			$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
+			unset($this->rowset[$query_id]);
+			unset($this->row[$query_id]);
 
-			unset($this->rowset[$cur_index]);
-			unset($this->row[$cur_index]);
-			
 			$result = array();
-			while ($this->rowset[$cur_index] = $this->sql_fetchrow($query_id))
+			while ($this->rowset[$query_id] = $this->sql_fetchrow($query_id))
 			{
-				$result[] = $this->rowset[$cur_index];
+				$result[] = $this->rowset[$query_id];
 			}
 			return $result;
 		}
-
+		
 		return false;
 	}
 
@@ -319,30 +314,26 @@ class sql_db
 		{
 			if ($rownum > -1)
 			{
-				@mysqli_data_seek($query_id, $rownum);
-				$row = @mysqli_fetch_assoc($query_id);
-				$result = isset($row[$field]) ? $row[$field] : false;
+				$result = @mysql_result($query_id, $rownum, $field);
 			}
 			else
 			{
-				$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
-	
-				if (empty($this->row[$cur_index]) && empty($this->rowset[$cur_index]))
+				if (empty($this->row[$query_id]) && empty($this->rowset[$query_id]))
 				{
-					if ($this->row[$cur_index] = $this->sql_fetchrow($query_id))
+					if ($this->sql_fetchrow($query_id))
 					{
-						$result = $this->row[$cur_index][$field];
+						$result = $this->row[$query_id][$field];
 					}
 				}
 				else
 				{
-					if ($this->rowset[$cur_index])
+					if ($this->rowset[$query_id])
 					{
-						$result = $this->rowset[$cur_index][$field];
+						$result = $this->rowset[$query_id][$field];
 					}
-					elseif ($this->row[$cur_index])
+					elseif ($this->row[$query_id])
 					{
-						$result = $this->row[$cur_index][$field];
+						$result = $this->row[$query_id][$field];
 					}
 				}
 			}
@@ -358,12 +349,12 @@ class sql_db
 			$query_id = $this->query_result;
 		}
 
-		return ($query_id) ? @mysqli_data_seek($query_id, $rownum) : false;
+		return ($query_id) ? @mysql_data_seek($query_id, $rownum) : false;
 	}
 
 	function sql_nextid()
 	{
-		return ($this->db_connect_id) ? @mysqli_insert_id($this->db_connect_id) : false;
+		return ($this->db_connect_id) ? @mysql_insert_id($this->db_connect_id) : false;
 	}
 
 	function sql_freeresult($query_id = false)
@@ -373,25 +364,18 @@ class sql_db
 			$query_id = $this->query_result;
 		}
 
-		$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
-
-		unset($this->rowset[$cur_index]);
-		unset($this->row[$cur_index]);
-
-		if (is_object($query_id))
+		if (isset($this->open_queries[(int) $query_id]))
 		{
-			$this->indexed--;
-			return @mysqli_free_result($query_id);
-		}
-		else
-		{
-			return false;
+			unset($this->open_queries[(int) $query_id]);
+			return @mysql_free_result($query_id);
 		}
+
+		return false;
 	}
 
 	function sql_escape($msg)
 	{
-		return @mysqli_real_escape_string($this->db_connect_id, $msg);
+		return mysql_escape_string($msg);
 	}
 	
 	function sql_error($sql = '')
@@ -401,7 +385,7 @@ class sql_db
 			$this_page = (isset($_SERVER['PHP_SELF']) && !empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
 			$this_page .= '&' . ((isset($_SERVER['QUERY_STRING']) && !empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : (isset($_ENV['QUERY_STRING']) ? $_ENV['QUERY_STRING'] : ''));
 
-			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @mysqli_error($this->db_connect_id) . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
+			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @mysql_error() . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
 
 			if ($this->transaction)
 			{
@@ -412,8 +396,8 @@ class sql_db
 		}
 
 		$result = array(
-			'message'	=> @mysqli_error($this->db_connect_id),
-			'code'		=> @mysqli_errno($this->db_connect_id)
+			'message'	=> @mysql_error(),
+			'code'		=> @mysql_errno()
 		);
 
 		return $result;
@@ -476,9 +460,9 @@ class sql_db
 				{
 					$html_table = FALSE;
 
-					if ($result = @mysqli_query($this->db_connect_id, "EXPLAIN $explain_query"))
+					if ($result = mysql_query("EXPLAIN $explain_query", $this->db_connect_id))
 					{
-						while ($row = @mysqli_fetch_assoc($result))
+						while ($row = mysql_fetch_assoc($result))
 						{
 							if (!$html_table && sizeof($row))
 							{
@@ -517,8 +501,8 @@ class sql_db
 				$endtime = explode(' ', microtime());
 				$endtime = $endtime[0] + $endtime[1];
 
-				$result = @mysqli_query($this->db_connect_id, $query);
-				while ($void = @mysqli_fetch_assoc($result))
+				$result = mysql_query($query, $this->db_connect_id);
+				while ($void = mysql_fetch_assoc($result))
 				{
 					// Take the time spent on parsing rows into account
 				}
@@ -536,7 +520,7 @@ class sql_db
 				// Pad the start time to not interfere with page timing
 				$starttime += $time_db;
 
-				@mysqli_free_result($result);
+				mysql_free_result($result);
 				$cache_num_queries++;
 				break;
 
diff --git a/phpBB/includes/db/mysqli.php b/phpBB/includes/db/mysqli.php
new file mode 100644
index 0000000000..c4222ae4e5
--- /dev/null
+++ b/phpBB/includes/db/mysqli.php
@@ -0,0 +1,571 @@
+<?php
+/** 
+*
+* @package dbal_mysqli
+* @version $Id$
+* @copyright (c) 2005 phpBB Group 
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('SQL_LAYER'))
+{
+
+define('SQL_LAYER', 'mysqli');
+
+/**
+* @package dbal_mysqli
+* MySQLi Database Abstraction Layer
+* Minimum Requirement is MySQL 4.1+ and the mysqli-extension
+*/
+class sql_db
+{
+	var $db_connect_id;
+	var $query_result;
+	var $return_on_error = false;
+	var $transaction = false;
+	var $sql_time = 0;
+	var $num_queries = 0;
+	var $open_queries = array();
+
+	var $indexed = 0;
+
+	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port = false, $persistency = false)
+	{
+		$this->persistency = $persistency;
+		$this->user = $sqluser;
+		$this->server = $sqlserver . (($port) ? ':' . $port : '');
+		$this->dbname = $database;
+
+		$this->db_connect_id = ($this->persistency) ? @mysqli_pconnect($this->server, $this->user, $sqlpassword) : @mysqli_connect($this->server, $this->user, $sqlpassword);
+
+		if ($this->db_connect_id && $this->dbname != '')
+		{
+			if (@mysqli_select_db($this->db_connect_id, $this->dbname))
+			{
+				return $this->db_connect_id;
+			}
+		}
+
+		return $this->sql_error('');
+	}
+
+	//
+	// Other base methods
+	//
+	function sql_close()
+	{
+		if (!$this->db_connect_id)
+		{
+			return false;
+		}
+
+		if ($this->transaction)
+		{
+			@mysqli_commit($this->db_connect_id);
+		}
+
+		return @mysqli_close($this->db_connect_id);
+	}
+
+	function sql_return_on_error($fail = false)
+	{
+		$this->return_on_error = $fail;
+	}
+
+	function sql_num_queries()
+	{
+		return $this->num_queries;
+	}
+
+	function sql_transaction($status = 'begin')
+	{
+		switch ($status)
+		{
+			case 'begin':
+				$result = @mysqli_autocommit($this->db_connect_id, false);
+				$this->transaction = true;
+				break;
+
+			case 'commit':
+				$result = @mysqli_commit($this->db_connect_id);
+				@mysqli_autocommit($this->db_connect_id, true);
+				$this->transaction = false;
+
+				if (!$result)
+				{
+					@mysqli_rollback($this->db_connect_id);
+					@mysqli_autocommit($this->db_connect_id, true);
+				}
+				break;
+
+			case 'rollback':
+				$result = @mysqli_rollback($this->db_connect_id);
+				@mysqli_autocommit($this->db_connect_id, true);
+				$this->transaction = false;
+				break;
+
+			default:
+				$result = true;
+		}
+
+		return $result;
+	}
+
+	// Base query method
+	function sql_query($query = '', $cache_ttl = 0)
+	{
+		if ($query != '')
+		{
+			global $cache;
+
+			// EXPLAIN only in extra debug mode
+			if (defined('DEBUG_EXTRA'))
+			{
+				$this->sql_report('start', $query);
+			}
+
+			$this->query_result = ($cache_ttl && method_exists($cache, 'sql_load')) ? $cache->sql_load($query) : false;
+			
+			if (!$this->query_result)
+			{
+				$this->num_queries++;
+
+				if (($this->query_result = @mysqli_query($this->db_connect_id, $query)) === false)
+				{
+					$this->sql_error($query);
+				}
+
+				if (is_object($this->query_result))
+				{
+					$this->query_result->cur_index = $this->indexed++;
+				}
+
+				if (defined('DEBUG_EXTRA'))
+				{
+					$this->sql_report('stop', $query);
+				}
+
+				if ($cache_ttl && method_exists($cache, 'sql_save'))
+				{
+					$cache->sql_save($query, $this->query_result, $cache_ttl);
+				}
+			}
+			else if (defined('DEBUG_EXTRA'))
+			{
+				$this->sql_report('fromcache', $query);
+			}
+		}
+		else
+		{
+			return false;
+		}
+
+		return ($this->query_result) ? $this->query_result : false;
+	}
+
+	function sql_query_limit($query, $total, $offset = 0, $cache_ttl = 0) 
+	{ 
+		if ($query != '') 
+		{
+			$this->query_result = false; 
+
+			// if $total is set to 0 we do not want to limit the number of rows
+			if ($total == 0)
+			{
+				$total = -1;
+			}
+
+			$query .= "\n LIMIT " . ((!empty($offset)) ? $offset . ', ' . $total : $total);
+
+			return $this->sql_query($query, $cache_ttl); 
+		} 
+		else 
+		{ 
+			return false; 
+		} 
+	}
+
+	// Idea for this from Ikonboard
+	function sql_build_array($query, $assoc_ary = false)
+	{
+		if (!is_array($assoc_ary))
+		{
+			return false;
+		}
+
+		$fields = array();
+		$values = array();
+		if ($query == 'INSERT')
+		{
+			foreach ($assoc_ary as $key => $var)
+			{
+				$fields[] = $key;
+
+				if (is_null($var))
+				{
+					$values[] = 'NULL';
+				}
+				elseif (is_string($var))
+				{
+					$values[] = "'" . $this->sql_escape($var) . "'";
+				}
+				else
+				{
+					$values[] = (is_bool($var)) ? intval($var) : $var;
+				}
+			}
+
+			$query = ' (' . implode(', ', $fields) . ') VALUES (' . implode(', ', $values) . ')';
+		}
+		else if ($query == 'UPDATE' || $query == 'SELECT')
+		{
+			$values = array();
+			foreach ($assoc_ary as $key => $var)
+			{
+				if (is_null($var))
+				{
+					$values[] = "$key = NULL";
+				}
+				elseif (is_string($var))
+				{
+					$values[] = "$key = '" . $this->sql_escape($var) . "'";
+				}
+				else
+				{
+					$values[] = (is_bool($var)) ? "$key = " . intval($var) : "$key = $var";
+				}
+			}
+			$query = implode(($query == 'UPDATE') ? ', ' : ' AND ', $values);
+		}
+
+		return $query;
+	}
+
+	// Other query methods
+	//
+	// NOTE :: Want to remove _ALL_ reliance on sql_numrows from core code ...
+	//         don't want this here by a middle Milestone
+	function sql_numrows($query_id = false)
+	{
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		return ($query_id) ? @mysqli_num_rows($query_id) : false;
+	}
+
+	function sql_affectedrows()
+	{
+		return ($this->db_connect_id) ? @mysqli_affected_rows($this->db_connect_id) : false;
+	}
+
+	function sql_fetchrow($query_id = false)
+	{
+		global $cache;
+
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		if (!is_object($query_id) && isset($cache->sql_rowset[$query_id]))
+		{
+			return $cache->sql_fetchrow($query_id);
+		}
+
+		return ($query_id) ? @mysqli_fetch_assoc($query_id) : false;
+	}
+
+	function sql_fetchrowset($query_id = false)
+	{
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		if ($query_id)
+		{
+			$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
+
+			unset($this->rowset[$cur_index]);
+			unset($this->row[$cur_index]);
+			
+			$result = array();
+			while ($this->rowset[$cur_index] = $this->sql_fetchrow($query_id))
+			{
+				$result[] = $this->rowset[$cur_index];
+			}
+			return $result;
+		}
+
+		return false;
+	}
+
+	function sql_fetchfield($field, $rownum = -1, $query_id = false)
+	{
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		if ($query_id)
+		{
+			if ($rownum > -1)
+			{
+				@mysqli_data_seek($query_id, $rownum);
+				$row = @mysqli_fetch_assoc($query_id);
+				$result = isset($row[$field]) ? $row[$field] : false;
+			}
+			else
+			{
+				$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
+	
+				if (empty($this->row[$cur_index]) && empty($this->rowset[$cur_index]))
+				{
+					if ($this->row[$cur_index] = $this->sql_fetchrow($query_id))
+					{
+						$result = $this->row[$cur_index][$field];
+					}
+				}
+				else
+				{
+					if ($this->rowset[$cur_index])
+					{
+						$result = $this->rowset[$cur_index][$field];
+					}
+					elseif ($this->row[$cur_index])
+					{
+						$result = $this->row[$cur_index][$field];
+					}
+				}
+			}
+			return $result;
+		}
+		return false;
+	}
+
+	function sql_rowseek($rownum, $query_id = false)
+	{
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		return ($query_id) ? @mysqli_data_seek($query_id, $rownum) : false;
+	}
+
+	function sql_nextid()
+	{
+		return ($this->db_connect_id) ? @mysqli_insert_id($this->db_connect_id) : false;
+	}
+
+	function sql_freeresult($query_id = false)
+	{
+		if (!$query_id)
+		{
+			$query_id = $this->query_result;
+		}
+
+		$cur_index = (is_object($query_id)) ? $query_id->cur_index : $query_id;
+
+		unset($this->rowset[$cur_index]);
+		unset($this->row[$cur_index]);
+
+		if (is_object($query_id))
+		{
+			$this->indexed--;
+			return @mysqli_free_result($query_id);
+		}
+		else
+		{
+			return false;
+		}
+	}
+
+	function sql_escape($msg)
+	{
+		return @mysqli_real_escape_string($this->db_connect_id, $msg);
+	}
+	
+	function sql_error($sql = '')
+	{
+		if (!$this->return_on_error)
+		{
+			$this_page = (isset($_SERVER['PHP_SELF']) && !empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
+			$this_page .= '&' . ((isset($_SERVER['QUERY_STRING']) && !empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : (isset($_ENV['QUERY_STRING']) ? $_ENV['QUERY_STRING'] : ''));
+
+			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @mysqli_error($this->db_connect_id) . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
+
+			if ($this->transaction)
+			{
+				$this->sql_transaction('rollback');
+			}
+			
+			trigger_error($message, E_USER_ERROR);
+		}
+
+		$result = array(
+			'message'	=> @mysqli_error($this->db_connect_id),
+			'code'		=> @mysqli_errno($this->db_connect_id)
+		);
+
+		return $result;
+	}
+
+	function sql_report($mode, $query = '')
+	{
+		if (empty($_GET['explain']))
+		{
+			return;
+		}
+
+		global $db, $cache, $starttime, $phpbb_root_path;
+		static $curtime, $query_hold, $html_hold;
+		static $sql_report = '';
+		static $cache_num_queries = 0;
+
+		if (!$query && !empty($query_hold))
+		{
+			$query = $query_hold;
+		}
+
+		switch ($mode)
+		{
+			case 'display':
+				if (!empty($cache))
+				{
+					$cache->unload();
+				}
+				$db->sql_close();
+
+				$mtime = explode(' ', microtime());
+				$totaltime = $mtime[0] + $mtime[1] - $starttime;
+
+				echo '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html; charset=iso-8869-1"><meta http-equiv="Content-Style-Type" content="text/css"><link rel="stylesheet" href="' . $phpbb_root_path . 'adm/subSilver.css" type="text/css"><style type="text/css">' . "\n";
+				echo 'th { background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic3.gif\') }' . "\n";
+				echo 'td.cat	{ background-image: url(\'' . $phpbb_root_path . 'adm/images/cellpic1.gif\') }' . "\n";
+				echo '</style><title>' . $msg_title . '</title></head><body>';
+				echo '<table width="100%" cellspacing="0" cellpadding="0" border="0"><tr><td><a href="' . htmlspecialchars(preg_replace('/&explain=([^&]*)/', '', $_SERVER['REQUEST_URI'])) . '"><img src="' . $phpbb_root_path . 'adm/images/header_left.jpg" width="200" height="60" alt="phpBB Logo" title="phpBB Logo" border="0"/></a></td><td width="100%" background="' . $phpbb_root_path . 'adm/images/header_bg.jpg" height="60" align="right" nowrap="nowrap"><span class="maintitle">SQL Report</span> &nbsp; &nbsp; &nbsp;</td></tr></table><br clear="all"/><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td height="40" align="center" valign="middle"><b>Page generated in ' . round($totaltime, 4) . " seconds with {$this->num_queries} queries" . (($cache_num_queries) ? " + $cache_num_queries " . (($cache_num_queries == 1) ? 'query' : 'queries') . ' returning data from cache' : '') . '</b></td></tr><tr><td align="center" nowrap="nowrap">Time spent on MySQL queries: <b>' . round($this->sql_time, 5) . 's</b> | Time spent on PHP: <b>' . round($totaltime - $this->sql_time, 5) . 's</b></td></tr></table><table width="95%" cellspacing="1" cellpadding="4" border="0" align="center"><tr><td>';
+				echo $sql_report;
+				echo '</td></tr></table><br /></body></html>';
+				exit;
+				break;
+
+			case 'start':
+				$query_hold = $query;
+				$html_hold = '';
+
+				$explain_query = $query;
+				if (preg_match('/UPDATE ([a-z0-9_]+).*?WHERE(.*)/s', $query, $m))
+				{
+					$explain_query = 'SELECT * FROM ' . $m[1] . ' WHERE ' . $m[2];
+				}
+				elseif (preg_match('/DELETE FROM ([a-z0-9_]+).*?WHERE(.*)/s', $query, $m))
+				{
+					$explain_query = 'SELECT * FROM ' . $m[1] . ' WHERE ' . $m[2];
+				}
+
+				if (preg_match('/^SELECT/', $explain_query))
+				{
+					$html_table = FALSE;
+
+					if ($result = @mysqli_query($this->db_connect_id, "EXPLAIN $explain_query"))
+					{
+						while ($row = @mysqli_fetch_assoc($result))
+						{
+							if (!$html_table && sizeof($row))
+							{
+								$html_table = TRUE;
+								$html_hold .= '<table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0" align="center"><tr>';
+								
+								foreach (array_keys($row) as $val)
+								{
+									$html_hold .= '<th nowrap="nowrap">' . (($val) ? ucwords(str_replace('_', ' ', $val)) : '&nbsp;') . '</th>';
+								}
+								$html_hold .= '</tr>';
+							}
+							$html_hold .= '<tr>';
+
+							$class = 'row1';
+							foreach (array_values($row) as $val)
+							{
+								$class = ($class == 'row1') ? 'row2' : 'row1';
+								$html_hold .= '<td class="' . $class . '">' . (($val) ? $val : '&nbsp;') . '</td>';
+							}
+							$html_hold .= '</tr>';
+						}
+					}
+
+					if ($html_table)
+					{
+						$html_hold .= '</table>';
+					}
+				}
+
+				$curtime = explode(' ', microtime());
+				$curtime = $curtime[0] + $curtime[1];
+				break;
+
+			case 'fromcache':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$result = @mysqli_query($this->db_connect_id, $query);
+				while ($void = @mysqli_fetch_assoc($result))
+				{
+					// Take the time spent on parsing rows into account
+				}
+				$splittime = explode(' ', microtime());
+				$splittime = $splittime[0] + $splittime[1];
+
+				$time_cache = $endtime - $curtime;
+				$time_db = $splittime - $endtime;
+				$color = ($time_db > $time_cache) ? 'green' : 'red';
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query results obtained from the cache</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table><p align="center">';
+
+				$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed [cache]: <b style="color: ' . $color . '">' . sprintf('%.5f', ($time_cache)) . 's</b> | Elapsed [db]: <b>' . sprintf('%.5f', $time_db) . 's</b></p>';
+
+				// Pad the start time to not interfere with page timing
+				$starttime += $time_db;
+
+				@mysqli_free_result($result);
+				$cache_num_queries++;
+				break;
+
+			case 'stop':
+				$endtime = explode(' ', microtime());
+				$endtime = $endtime[0] + $endtime[1];
+
+				$sql_report .= '<hr width="100%"/><br /><table class="bg" width="100%" cellspacing="1" cellpadding="4" border="0"><tr><th>Query #' . $this->num_queries . '</th></tr><tr><td class="row1"><textarea style="font-family:\'Courier New\',monospace;width:100%" rows="5">' . preg_replace('/\t(AND|OR)(\W)/', "\$1\$2", htmlspecialchars(preg_replace('/[\s]*[\n\r\t]+[\n\r\s\t]*/', "\n", $query))) . '</textarea></td></tr></table> ' . $html_hold . '<p align="center">';
+
+				if ($this->query_result)
+				{
+					if (preg_match('/^(UPDATE|DELETE|REPLACE)/', $query))
+					{
+						$sql_report .= "Affected rows: <b>" . $this->sql_affectedrows($this->query_result) . '</b> | ';
+					}
+					$sql_report .= 'Before: ' . sprintf('%.5f', $curtime - $starttime) . 's | After: ' . sprintf('%.5f', $endtime - $starttime) . 's | Elapsed: <b>' . sprintf('%.5f', $endtime - $curtime) . 's</b>';
+				}
+				else
+				{
+					$error = $this->sql_error();
+					$sql_report .= '<b style="color: red">FAILED</b> - MySQL Error ' . $error['code'] . ': ' . htmlspecialchars($error['message']);
+				}
+
+				$sql_report .= '</p>';
+
+				$this->sql_time += $endtime - $curtime;
+				break;
+		}
+	}
+} // class sql_db
+
+} // if ... define
+
+?>
+\ No newline at end of file
diff --git a/phpBB/install/install.php b/phpBB/install/install.php
index b9bb36276e..2980c9eef1 100644
--- a/phpBB/install/install.php
+++ b/phpBB/install/install.php
@@ -92,13 +92,20 @@ $available_dbms = array(
 		'DELIM'			=> ';',
 		'COMMENTS'		=> 'remove_remarks'
 	),
-	'mysql4'	=> array(
-		'LABEL'			=> 'MySQL 4.1.x',
+	'mysqli'	=> array(
+		'LABEL'			=> 'MySQL 4.1.x (MySQLi)',
 		'SCHEMA'		=> 'mysql',
 		'MODULE'		=> 'mysqli', 
 		'DELIM'			=> ';',
 		'COMMENTS'		=> 'remove_remarks'
 	),
+	'mysql4'	=> array(
+		'LABEL'			=> 'MySQL 4',
+		'SCHEMA'		=> 'mysql',
+		'MODULE'		=> 'mysql', 
+		'DELIM'			=> ';',
+		'COMMENTS'		=> 'remove_remarks'
+	),
 	'mssql'		=> array(
 		'LABEL'			=> 'MS SQL Server 7/2000',
 		'SCHEMA'		=> 'mssql',
@@ -106,13 +113,6 @@ $available_dbms = array(
 		'DELIM'			=> 'GO',
 		'COMMENTS'		=> 'remove_comments'
 	),
-	'msaccess' => array(
-		'LABEL'			=> 'MS Access [ ODBC ]',
-		'SCHEMA'		=> '',
-		'MODULE'		=> 'odbc', 
-		'DELIM'			=> '',
-		'COMMENTS'		=> ''
-	),
 	'mssql-odbc'=>	array(
 		'LABEL'			=> 'MS SQL Server [ ODBC ]',
 		'SCHEMA'		=> 'mssql',
@@ -1402,6 +1402,7 @@ function connect_check_db($error_connect, &$error, &$dbms, &$table_prefix, &$dbh
 		{
 			case 'mysql':
 			case 'mysql4':
+			case 'mysqli':
 				$sql = "SHOW TABLES";
 				$field = "Tables_in_{$dbname}";
 				break;
@@ -1414,13 +1415,6 @@ function connect_check_db($error_connect, &$error, &$dbms, &$table_prefix, &$dbh
 				$field = "name";
 				break;
 
-			case 'msaccess':
-				$sql = 'SELECT * FROM MSysObjects
-					WHERE Type = 1
-						AND Name Not Like "MSys*"';
-				$field = "Name";
-				break;
-
 			case 'postgres':
 				$sql = "SELECT relname 
 					FROM pg_class 
diff --git a/phpBB/install/schemas/mssql_schema.sql b/phpBB/install/schemas/mssql_schema.sql
index 789505768b..a07eda57d7 100644
--- a/phpBB/install/schemas/mssql_schema.sql
+++ b/phpBB/install/schemas/mssql_schema.sql
@@ -1407,12 +1407,6 @@ ALTER TABLE [phpbb_ranks] WITH NOCHECK ADD
 	CONSTRAINT [DF_ranks__rank_special] DEFAULT (0) FOR [rank_special]
 GO
 
-ALTER TABLE [phpbb_ratings] WITH NOCHECK ADD 
-	CONSTRAINT [DF_rating_post_id] DEFAULT (0) FOR [post_id],
-	CONSTRAINT [DF_rating_user_id] DEFAULT (0) FOR [user_id],
-	CONSTRAINT [DF_rating_rating] DEFAULT (0) FOR [rating]
-GO
-
 ALTER TABLE [phpbb_reports] WITH NOCHECK ADD 
 	CONSTRAINT [DF_report_reason_id] DEFAULT (0) FOR [reason_id],
 	CONSTRAINT [DF_report_post_id] DEFAULT (0) FOR [post_id],
diff --git a/phpBB/language/en/admin.php b/phpBB/language/en/admin.php
index 08b032870a..342eaa0d31 100644
--- a/phpBB/language/en/admin.php
+++ b/phpBB/language/en/admin.php
@@ -1933,9 +1933,9 @@ $lang += array(
 	'DLL_FIREBIRD'		=> 'Firebird 1.5+',
 	'DLL_MYSQL'			=> 'MySQL 3.23.x/4.x',
 	'DLL_MYSQL4'		=> 'MySQL 4.1+',
+	'DLL_MYSQLI'		=> 'MySQL 4.1+ with MySQLi Extension',
 	'DLL_MSSQL'			=> 'MSSQL Server 2000',
 	'DLL_MSSQL-ODBC'	=> 'MSSQL Server 2000 via ODBC',
-	'DLL_MSACCESS'		=> 'MS Access via ODBC',
 	'DLL_ORACLE'		=> 'Oracle',
 	'DLL_POSTGRES'		=> 'PostgreSQL 7.x',
 	'DLL_SQLITE'		=> 'SQLite',