From b52f751b306b1036718112df6307fedd283eeea6 Mon Sep 17 00:00:00 2001
From: Alexander Ebert <ebert@woltlab.com>
Date: Thu, 4 Sep 2014 19:55:42 +0200
Subject: [PATCH] Search overhaul (WIP)

---
 com.woltlab.wcf/option.xml                    |  12 +
 .../acp/action/InstallPackageAction.class.php |   2 +-
 .../files/lib/form/SearchForm.class.php       |   9 +-
 ...mentMessageEmbeddedObjectHandler.class.php |  11 +-
 .../search/AbstractSearchEngine.class.php     |  16 ++
 .../AbstractSearchIndexManager.class.php      |  49 ++++
 .../lib/system/search/ISearchEngine.class.php |  29 +++
 .../search/ISearchIndexManager.class.php      |  66 +++++
 .../lib/system/search/SearchEngine.class.php  | 241 ++---------------
 .../search/SearchIndexManager.class.php       | 176 +++----------
 .../search/mysql/MysqlSearchEngine.class.php  | 244 ++++++++++++++++++
 .../mysql/MysqlSearchIndexManager.class.php   | 124 +++++++++
 wcfsetup/install/files/options.inc.php        |   1 +
 13 files changed, 621 insertions(+), 359 deletions(-)
 create mode 100644 wcfsetup/install/files/lib/system/search/AbstractSearchEngine.class.php
 create mode 100644 wcfsetup/install/files/lib/system/search/AbstractSearchIndexManager.class.php
 create mode 100644 wcfsetup/install/files/lib/system/search/ISearchEngine.class.php
 create mode 100644 wcfsetup/install/files/lib/system/search/ISearchIndexManager.class.php
 create mode 100644 wcfsetup/install/files/lib/system/search/mysql/MysqlSearchEngine.class.php
 create mode 100644 wcfsetup/install/files/lib/system/search/mysql/MysqlSearchIndexManager.class.php

diff --git a/com.woltlab.wcf/option.xml b/com.woltlab.wcf/option.xml
index 3de93ba5a8..46233f57ef 100644
--- a/com.woltlab.wcf/option.xml
+++ b/com.woltlab.wcf/option.xml
@@ -54,6 +54,9 @@
 					<category name="general.system.image">
 						<parent>general.system</parent>
 					</category>
+					<category name="general.system.search">
+						<parent>general.system</parent>
+					</category>
 					<category name="general.system.date">
 						<parent>general.system</parent>
 					</category>
@@ -455,6 +458,15 @@ imagick:wcf.acp.option.image_adapter_type.imagick]]>
 			</option>
 			<!-- /general.system.image -->
 			
+			<!-- general.system.search -->
+			<option name="search_engine">
+				<categoryname>general.system.search</categoryname>
+				<optiontype>radioButton</optiontype>
+				<defaultvalue><![CDATA[mysql]]></defaultvalue>
+				<selectoptions><![CDATA[mysql:wcf.acp.option.search_engine.mysql]]></selectoptions>
+			</option>
+			<!-- /general.system.search -->
+			
 			<!-- general.system.cookie -->
 			<option name="cookie_prefix">
 				<categoryname>general.system.cookie</categoryname>
diff --git a/wcfsetup/install/files/lib/acp/action/InstallPackageAction.class.php b/wcfsetup/install/files/lib/acp/action/InstallPackageAction.class.php
index 2f498fdb93..2b943c3bc1 100755
--- a/wcfsetup/install/files/lib/acp/action/InstallPackageAction.class.php
+++ b/wcfsetup/install/files/lib/acp/action/InstallPackageAction.class.php
@@ -231,7 +231,7 @@ class InstallPackageAction extends AbstractDialogAction {
 	 */
 	protected function finalize() {
 		// create search index tables
-		SearchIndexManager::createSearchIndexTables();
+		SearchIndexManager::getInstance()->createSearchIndices();
 		
 		CacheHandler::getInstance()->flushAll();
 	}
diff --git a/wcfsetup/install/files/lib/form/SearchForm.class.php b/wcfsetup/install/files/lib/form/SearchForm.class.php
index eaf456ca92..2ba150d69c 100644
--- a/wcfsetup/install/files/lib/form/SearchForm.class.php
+++ b/wcfsetup/install/files/lib/form/SearchForm.class.php
@@ -3,7 +3,6 @@ namespace wcf\form;
 use wcf\data\search\Search;
 use wcf\data\search\SearchAction;
 use wcf\system\application\ApplicationHandler;
-use wcf\system\database\util\PreparedStatementConditionBuilder;
 use wcf\system\exception\IllegalLinkException;
 use wcf\system\exception\NamedUserException;
 use wcf\system\exception\PermissionDeniedException;
@@ -115,6 +114,12 @@ class SearchForm extends AbstractCaptchaForm {
 	 */
 	public $searchIndexCondition = null;
 	
+	/**
+	 * class name for $searchIndexCondition object
+	 * @var	string
+	 */
+	public $searchIndexConditionClassName = 'wcf\system\database\util\PreparedStatementConditionBuilder';
+	
 	/**
 	 * search hash to modify existing search
 	 * @var	string
@@ -414,7 +419,7 @@ class SearchForm extends AbstractCaptchaForm {
 		
 		// default conditions
 		$userIDs = $this->getUserIDs();
-		$this->searchIndexCondition = new PreparedStatementConditionBuilder(false);
+		$this->searchIndexCondition = new $this->searchIndexConditionClassName(false);
 		
 		// user ids
 		if (!empty($userIDs)) {
diff --git a/wcfsetup/install/files/lib/system/message/embedded/object/AttachmentMessageEmbeddedObjectHandler.class.php b/wcfsetup/install/files/lib/system/message/embedded/object/AttachmentMessageEmbeddedObjectHandler.class.php
index 79003b5a7b..ade25c57ff 100644
--- a/wcfsetup/install/files/lib/system/message/embedded/object/AttachmentMessageEmbeddedObjectHandler.class.php
+++ b/wcfsetup/install/files/lib/system/message/embedded/object/AttachmentMessageEmbeddedObjectHandler.class.php
@@ -26,10 +26,13 @@ class AttachmentMessageEmbeddedObjectHandler extends AbstractMessageEmbeddedObje
 				if ($parsedAttachmentID) $attachmentIDs[] = $parsedAttachmentID;
 			}
 			
-			$attachmentList = new AttachmentList();
-			$attachmentList->getConditionBuilder()->add("attachment.attachmentID IN (?)", array($attachmentIDs));
-			$attachmentList->readObjectIDs();
-			return $attachmentList->getObjectIDs();
+			if (!empty($attachmentIDs)) {
+				$attachmentList = new AttachmentList();
+				$attachmentList->getConditionBuilder()->add("attachment.attachmentID IN (?)", array($attachmentIDs));
+				$attachmentList->readObjectIDs();
+				
+				return $attachmentList->getObjectIDs();
+			}
 		}
 		
 		return false;
diff --git a/wcfsetup/install/files/lib/system/search/AbstractSearchEngine.class.php b/wcfsetup/install/files/lib/system/search/AbstractSearchEngine.class.php
new file mode 100644
index 0000000000..f1ba8fe598
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/AbstractSearchEngine.class.php
@@ -0,0 +1,16 @@
+<?php
+namespace wcf\system\search;
+use wcf\system\SingletonFactory;
+
+/**
+ * Default implementation for search engines, this class should be extended by
+ * all search engines to preserve compatibility in case of interface changes.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+abstract class AbstractSearchEngine extends SingletonFactory implements ISearchEngine { }
diff --git a/wcfsetup/install/files/lib/system/search/AbstractSearchIndexManager.class.php b/wcfsetup/install/files/lib/system/search/AbstractSearchIndexManager.class.php
new file mode 100644
index 0000000000..3449d5d504
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/AbstractSearchIndexManager.class.php
@@ -0,0 +1,49 @@
+<?php
+namespace wcf\system\search;
+use wcf\data\object\type\ObjectType;
+use wcf\data\object\type\ObjectTypeList;
+use wcf\system\SingletonFactory;
+use wcf\system\WCF;
+
+/**
+ * Default implementation for search index managers, this class should be extended by
+ * all search index managers to preserve compatibility in case of interface changes.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+abstract class AbstractSearchIndexManager extends SingletonFactory implements ISearchIndexManager {
+	/**
+	 * @see	\wcf\system\search\ISearchIndexManager::createSearchIndices()
+	 */
+	public function createSearchIndices() {
+		// get definition id
+		$sql = "SELECT	definitionID
+			FROM	wcf".WCF_N."_object_type_definition
+			WHERE	definitionName = ?";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute(array('com.woltlab.wcf.searchableObjectType'));
+		$row = $statement->fetchArray();
+		
+		$objectTypeList = new ObjectTypeList();
+		$objectTypeList->getConditionBuilder()->add("object_type.definitionID = ?", array($row['definitionID']));
+		$objectTypeList->readObjects();
+		
+		foreach ($objectTypeList as $objectType) {
+			$this->createSearchIndex($objectType);
+		}
+	}
+	
+	/**
+	 * Creates the search index for given object type. Returns true if the
+	 * index was created, otherwise false.
+	 * 
+	 * @param	\wcf\data\object\type\ObjectType	$objectType
+	 * @return	boolean
+	 */
+	abstract protected function createSearchIndex(ObjectType $objectType);
+}
diff --git a/wcfsetup/install/files/lib/system/search/ISearchEngine.class.php b/wcfsetup/install/files/lib/system/search/ISearchEngine.class.php
new file mode 100644
index 0000000000..e6398753ac
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/ISearchEngine.class.php
@@ -0,0 +1,29 @@
+<?php
+namespace wcf\system\search;
+use wcf\system\database\util\PreparedStatementConditionBuilder;
+
+/**
+ * Default interface for search engines.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+interface ISearchEngine {
+	/**
+	 * Searches for the given string and returns the data of the found messages.
+	 *
+	 * @param	string								$q
+	 * @param	array								$objectTypes
+	 * @param	boolean								$subjectOnly
+	 * @param	\wcf\system\database\util\PreparedStatementConditionBuilder	$searchIndexCondition
+	 * @param	array								$additionalConditions
+	 * @param	string								$orderBy
+	 * @param	integer								$limit
+	 * @return	array
+	 */
+	public function search($q, array $objectTypes, $subjectOnly = false, PreparedStatementConditionBuilder $searchIndexCondition = null, array $additionalConditions = array(), $orderBy = 'time DESC', $limit = 1000);
+}
diff --git a/wcfsetup/install/files/lib/system/search/ISearchIndexManager.class.php b/wcfsetup/install/files/lib/system/search/ISearchIndexManager.class.php
new file mode 100644
index 0000000000..0f26731630
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/ISearchIndexManager.class.php
@@ -0,0 +1,66 @@
+<?php
+namespace wcf\system\search;
+
+/**
+ * Default interface for search index managers.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+interface ISearchIndexManager {
+	/**
+	 * Adds a new entry.
+	 * 
+	 * @param	string		$objectType
+	 * @param	integer		$objectID
+	 * @param	string		$message
+	 * @param	string		$subject
+	 * @param	integer		$time
+	 * @param	integer		$userID
+	 * @param	string		$username
+	 * @param	integer		$languageID
+	 * @param	string		$metaData
+	 * @param	array<mixed>	$additionalData
+	 */
+	public function add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array());
+	
+	/**
+	 * Updates the search index.
+	 * 
+	 * @param	string		$objectType
+	 * @param	integer		$objectID
+	 * @param	string		$message
+	 * @param	string		$subject
+	 * @param	integer		$time
+	 * @param	integer		$userID
+	 * @param	string		$username
+	 * @param	integer		$languageID
+	 * @param	string		$metaData
+	 * @param	array<mixed>	$additionalData
+	 */
+	public function update($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array());
+	
+	/**
+	 * Deletes search index entries.
+	 * 
+	 * @param	string		$objectType
+	 * @param	array<integer>	$objectIDs
+	 */
+	public function delete($objectType, array $objectIDs);
+	
+	/**
+	 * Resets the search index.
+	 * 
+	 * @param	string		$objectType
+	 */
+	public function reset($objectType);
+	
+	/**
+	 * Creates the search index for all searchable objects.
+	 */
+	public function createSearchIndices();
+}
diff --git a/wcfsetup/install/files/lib/system/search/SearchEngine.class.php b/wcfsetup/install/files/lib/system/search/SearchEngine.class.php
index c6370063cb..fafabced1b 100644
--- a/wcfsetup/install/files/lib/system/search/SearchEngine.class.php
+++ b/wcfsetup/install/files/lib/system/search/SearchEngine.class.php
@@ -2,11 +2,7 @@
 namespace wcf\system\search;
 use wcf\data\object\type\ObjectTypeCache;
 use wcf\system\database\util\PreparedStatementConditionBuilder;
-use wcf\system\database\DatabaseException;
-use wcf\system\exception\SystemException;
 use wcf\system\SingletonFactory;
-use wcf\system\WCF;
-use wcf\util\StringUtil;
 
 /**
  * SearchEngine searches for given query in the selected object types.
@@ -18,7 +14,7 @@ use wcf\util\StringUtil;
  * @subpackage	system.search
  * @category	Community Framework
  */
-class SearchEngine extends SingletonFactory {
+class SearchEngine extends SingletonFactory implements ISearchEngine {
 	/**
 	 * list of available object types
 	 * @var	array
@@ -26,10 +22,10 @@ class SearchEngine extends SingletonFactory {
 	protected $availableObjectTypes = array();
 	
 	/**
-	 * MySQL's minimum word length for fulltext indices
-	 * @var	integer
+	 * search engine object
+	 * @var	\wcf\system\search\ISearchEngine
 	 */
-	protected static $ftMinWordLen = null;
+	protected $searchEngine = null;
 	
 	/**
 	 * @see	\wcf\system\SingletonFactory::init()
@@ -68,226 +64,35 @@ class SearchEngine extends SingletonFactory {
 	}
 	
 	/**
-	 * Searches for the given string and returns the data of the found messages.
+	 * Returns the search engine object.
 	 * 
-	 * @param	string								$q
-	 * @param	array								$objectTypes
-	 * @param	boolean								$subjectOnly
-	 * @param	\wcf\system\database\util\PreparedStatementConditionBuilder	$searchIndexCondition
-	 * @param	array								$additionalConditions
-	 * @param	string								$orderBy
-	 * @param	integer								$limit
-	 * @return	array
+	 * @return	\wcf\system\search\ISearchEngine
 	 */
-	public function search($q, array $objectTypes, $subjectOnly = false, PreparedStatementConditionBuilder $searchIndexCondition = null, array $additionalConditions = array(), $orderBy = 'time DESC', $limit = 1000) {
-		// handle sql types
-		$fulltextCondition = null;
-		$relevanceCalc = '';
-		if (!empty($q)) {
-			$q = $this->parseSearchQuery($q);
-			
-			$fulltextCondition = new PreparedStatementConditionBuilder(false);
-			switch (WCF::getDB()->getDBType()) {
-				case 'wcf\system\database\MySQLDatabase':
-					$fulltextCondition->add("MATCH (subject".(!$subjectOnly ? ', message, metaData' : '').") AGAINST (? IN BOOLEAN MODE)", array($q));
-				break;
-				
-				case 'wcf\system\database\PostgreSQLDatabase':
-					// replace * with :*
-					$q = str_replace('*', ':*', $q);
-					
-					$fulltextCondition->add("fulltextIndex".($subjectOnly ? "SubjectOnly" : '')." @@ to_tsquery(?)", array($q));
-				break;
-				
-				default:
-					throw new SystemException("your database type doesn't support fulltext search");
-			}
-			
-			if ($orderBy == 'relevance ASC' || $orderBy == 'relevance DESC') {
-				switch (WCF::getDB()->getDBType()) {
-					case 'wcf\system\database\MySQLDatabase':
-						$relevanceCalc = "MATCH (subject".(!$subjectOnly ? ', message, metaData' : '').") AGAINST ('".escapeString($q)."') + (5 / (1 + POW(LN(1 + (".TIME_NOW." - time) / 2592000), 2))) AS relevance";
-					break;
-					
-					case 'wcf\system\database\PostgreSQLDatabase':
-						$relevanceCalc = "ts_rank_cd(fulltextIndex".($subjectOnly ? "SubjectOnly" : '').", '".escapeString($q)."') AS relevance";
-					break;
+	protected function getSearchEngine() {
+		if ($this->searchEngine === null) {
+			$className = '';
+			if (SEARCH_ENGINE != 'mysql') {
+				$className = 'wcf\system\search\\'.SEARCH_ENGINE.'\\'.ucfirst(SEARCH_ENGINE).'SearchEngine';
+				if (!class_exists($className)) {
+					$className = '';
 				}
 			}
-		}
-		
-		// build search query
-		$sql = '';
-		$parameters = array();
-		foreach ($objectTypes as $objectTypeName) {
-			$objectType = $this->getObjectType($objectTypeName);
-			if (!empty($sql)) $sql .= "\nUNION\n";
-			$additionalConditionsConditionBuilder = (isset($additionalConditions[$objectTypeName]) ? $additionalConditions[$objectTypeName] : null);
-			if (($specialSQL = $objectType->getSpecialSQLQuery($fulltextCondition, $searchIndexCondition, $additionalConditionsConditionBuilder, $orderBy))) {
-				$sql .= "(".$specialSQL.")";
-			}
-			else {
-				$sql .= "(
-					SELECT		".$objectType->getIDFieldName()." AS objectID,
-							".$objectType->getSubjectFieldName()." AS subject,
-							".$objectType->getTimeFieldName()." AS time,
-							".$objectType->getUsernameFieldName()." AS username,
-							'".$objectTypeName."' AS objectType
-							".($relevanceCalc ? ',search_index.relevance' : '')."
-					FROM		".$objectType->getTableName()."
-					INNER JOIN	(
-								SELECT		objectID
-										".($relevanceCalc ? ','.$relevanceCalc : '')."
-								FROM		".SearchIndexManager::getTableName($objectTypeName)."
-								WHERE		".($fulltextCondition !== null ? $fulltextCondition : '')."
-										".(($searchIndexCondition !== null && $searchIndexCondition->__toString()) ? ($fulltextCondition !== null ? "AND " : '').$searchIndexCondition : '')."
-								".(!empty($orderBy) && $fulltextCondition === null ? 'ORDER BY '.$orderBy : '')."
-								LIMIT		1000
-							) search_index
-					ON		(".$objectType->getIDFieldName()." = search_index.objectID)
-					".$objectType->getJoins()."
-					".(isset($additionalConditions[$objectTypeName]) ? $additionalConditions[$objectTypeName] : '')."
-				)";
-			}
-			
-			if ($fulltextCondition !== null) $parameters = array_merge($parameters, $fulltextCondition->getParameters());
-			if ($searchIndexCondition !== null) $parameters = array_merge($parameters, $searchIndexCondition->getParameters());
-			if (isset($additionalConditions[$objectTypeName])) $parameters = array_merge($parameters, $additionalConditions[$objectTypeName]->getParameters());
-		}
-		if (empty($sql)) {
-			throw new SystemException('no object types given');
-		}
-		
-		if (!empty($orderBy)) {
-			$sql .= " ORDER BY " . $orderBy;
-		}
-		
-		// send search query
-		$messages = array();
-		$statement = WCF::getDB()->prepareStatement($sql, $limit);
-		$statement->execute($parameters);
-		while ($row = $statement->fetchArray()) {
-			$messages[] = array(
-				'objectID' => $row['objectID'],
-				'objectType' => $row['objectType']
-			);
-		}
-		
-		return $messages;
-	}
-	
-	/**
-	 * Manipulates the search term (< and > used as quotation marks):
-	 * 
-	 * - <test foo> becomes <+test* +foo*>
-	 * - <test -foo bar> becomes <+test* -foo* +bar*>
-	 * - <test "foo bar"> becomes <+test* +"foo bar">
-	 * 
-	 * @see	http://dev.mysql.com/doc/refman/5.5/en/fulltext-boolean.html
-	 * 
-	 * @param	string		$query
-	 */
-	protected function parseSearchQuery($query) {
-		$query = StringUtil::trim($query);
-		
-		// expand search terms with a * unless they're encapsulated with quotes
-		$inQuotes = false;
-		$previousChar = $tmp = '';
-		$controlCharacterOrSpace = false;
-		$chars = array('+', '-', '*');
-		$ftMinWordLen = self::getFulltextMinimumWordLength();
-		for ($i = 0, $length = mb_strlen($query); $i < $length; $i++) {
-			$char = mb_substr($query, $i, 1);
-			
-			if ($inQuotes) {
-				if ($char == '"') {
-					$inQuotes = false;
-				}
-			}
-			else {
-				if ($char == '"') {
-					$inQuotes = true;
-				}
-				else {
-					if ($char == ' ' && !$controlCharacterOrSpace) {
-						$controlCharacterOrSpace = true;
-						$tmp .= '*';
-					}
-					else if (in_array($char, $chars)) {
-						$controlCharacterOrSpace = true;
-					}
-					else {
-						$controlCharacterOrSpace = false;
-					}
-				}
-			}
-			
-			/*
-			 * prepend a plus sign (logical AND) if ALL these conditions are given:
-			 * 
-			 * 1) previous character:
-			 *   - is empty (start of string)
-			 *   - is a space (MySQL uses spaces to separate words)
-			 * 
-			 * 2) not within quotation marks
-			 * 
-			 * 3) current char:
-			 *   - is NOT +, - or *
-			 */
-			if (($previousChar == '' || $previousChar == ' ') && !$inQuotes && !in_array($char, $chars)) {
-				// check if the term is shorter than MySQL's ft_min_word_len
 				
-				if ($i + $ftMinWordLen <= $length) {
-					$term = '';// $char;
-					for ($j = $i, $innerLength = $ftMinWordLen + $i; $j < $innerLength; $j++) {
-						$currentChar = mb_substr($query, $j, 1);
-						if ($currentChar == '"' || $currentChar == ' ' || in_array($currentChar, $chars)) {
-							break;
-						}
-						
-						$term .= $currentChar;
-					}
-					
-					if (mb_strlen($term) == $ftMinWordLen) {
-						$tmp .= '+';
-					}
-				}
+			// fallback to MySQL
+			if (empty($className)) {
+				$className = 'wcf\system\search\mysql\MysqlSearchEngine';
 			}
-			
-			$tmp .= $char;
-			$previousChar = $char;
-		}
-		
-		// handle last char
-		if (!$inQuotes && !$controlCharacterOrSpace) {
-			$tmp .= '*';
+				
+			$this->searchEngine = call_user_func(array($className, 'getInstance'));
 		}
-		
-		return $tmp;
+	
+		return $this->searchEngine;
 	}
 	
 	/**
-	 * Returns MySQL's minimum word length for fulltext indices.
-	 * 
-	 * @return	integer
+	 * @see	\wcf\system\search\ISearchEngine::search()
 	 */
-	public static function getFulltextMinimumWordLength() {
-		if (self::$ftMinWordLen === null) {
-			$sql = "SHOW VARIABLES LIKE ?";
-			$statement = WCF::getDB()->prepareStatement($sql);
-			
-			try {
-				$statement->execute(array('ft_min_word_len'));
-				$row = $statement->fetchArray();
-			}
-			catch (DatabaseException $e) {
-				// fallback if user is disallowed to issue 'SHOW VARIABLES'
-				$row = array('Value' => 4);
-			}
-			
-			self::$ftMinWordLen = $row['Value'];
-		}
-		
-		return self::$ftMinWordLen;
+	public function search($q, array $objectTypes, $subjectOnly = false, PreparedStatementConditionBuilder $searchIndexCondition = null, array $additionalConditions = array(), $orderBy = 'time DESC', $limit = 1000) {
+		return $this->getSearchEngine()->search($q, $objectTypes, $subjectOnly, $searchIndexCondition, $additionalConditions, $orderBy, $limit);
 	}
 }
diff --git a/wcfsetup/install/files/lib/system/search/SearchIndexManager.class.php b/wcfsetup/install/files/lib/system/search/SearchIndexManager.class.php
index cdcf593c9a..961ac96f25 100644
--- a/wcfsetup/install/files/lib/system/search/SearchIndexManager.class.php
+++ b/wcfsetup/install/files/lib/system/search/SearchIndexManager.class.php
@@ -1,13 +1,10 @@
 <?php
 namespace wcf\system\search;
-use wcf\data\object\type\ObjectType;
 use wcf\data\object\type\ObjectTypeCache;
-use wcf\data\object\type\ObjectTypeList;
 use wcf\data\package\Package;
 use wcf\data\package\PackageList;
 use wcf\system\exception\SystemException;
 use wcf\system\SingletonFactory;
-use wcf\system\WCF;
 
 /**
  * Manages the search index.
@@ -19,7 +16,7 @@ use wcf\system\WCF;
  * @subpackage	system.search
  * @category	Community Framework
  */
-class SearchIndexManager extends SingletonFactory {
+class SearchIndexManager extends SingletonFactory implements ISearchIndexManager {
 	/**
 	 * list of available object types
 	 * @var	array
@@ -32,6 +29,12 @@ class SearchIndexManager extends SingletonFactory {
 	 */
 	protected static $packages = array();
 	
+	/**
+	 * search index manager object
+	 * @var	\wcf\system\search\ISearchIndexManager
+	 */
+	protected $searchIndexManager = null;
+	
 	/**
 	 * @see	\wcf\system\SingletonFactory::init()
 	 */
@@ -69,159 +72,64 @@ class SearchIndexManager extends SingletonFactory {
 	}
 	
 	/**
-	 * Adds a new entry.
+	 * Returns the search index manager object.
 	 * 
-	 * @param	string		$objectType
-	 * @param	integer		$objectID
-	 * @param	string		$message
-	 * @param	string		$subject
-	 * @param	integer		$time
-	 * @param	integer		$userID
-	 * @param	string		$username
-	 * @param	integer		$languageID
-	 * @param	string		$metaData
+	 * @return	\wcf\system\search\ISearchIndexManager
 	 */
-	public function add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '') {
-		if ($languageID === null) $languageID = 0;
+	protected function getSearchIndexManager() {
+		if ($this->searchIndexManager === null) {
+			$className = '';
+			if (SEARCH_ENGINE != 'mysql') {
+				$className = 'wcf\system\search\\'.SEARCH_ENGINE.'\\'.ucfirst(SEARCH_ENGINE).'SearchEngine';
+				if (!class_exists($className)) {
+					$className = '';
+				}
+			}
+			
+			// fallback to MySQL
+			if (empty($className)) {
+				$className = 'wcf\system\search\mysql\MysqlSearchIndexManager';
+			}
+			
+			$this->searchIndexManager = call_user_func(array($className, 'getInstance'));
+		}
 		
-		// save new entry
-		$sql = "REPLACE INTO	" . self::getTableName($objectType) . "
-					(objectID, subject, message, time, userID, username, languageID, metaData)
-			VALUES		(?, ?, ?, ?, ?, ?, ?, ?)";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute(array($objectID, $subject, $message, $time, $userID, $username, $languageID, $metaData));
+		return $this->searchIndexManager;
 	}
 	
 	/**
-	 * Updates the search index.
-	 * 
-	 * @param	string		$objectType
-	 * @param	integer		$objectID
-	 * @param	string		$message
-	 * @param	string		$subject
-	 * @param	integer		$time
-	 * @param	integer		$userID
-	 * @param	string		$username
-	 * @param	integer		$languageID
-	 * @param	string		$metaData
+	 * @see	\wcf\system\search\ISearchIndexManager::add()
 	 */
-	public function update($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '') {
-		// delete existing entry
-		$this->delete($objectType, array($objectID));
-		
-		// save new entry
-		$this->add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID, $metaData);
+	public function add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array()) {
+		$this->getSearchIndexManager()->add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID, $metaData, $additionalData);
 	}
 	
 	/**
-	 * Deletes search index entries.
-	 * 
-	 * @param	string		$objectType
-	 * @param	array<integer>	$objectIDs
+	 * @see	\wcf\system\search\ISearchIndexManager::update()
 	 */
-	public function delete($objectType, array $objectIDs) {
-		$sql = "DELETE FROM	" . self::getTableName($objectType) . "
-			WHERE		objectID = ?";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		WCF::getDB()->beginTransaction();
-		foreach ($objectIDs as $objectID) {
-			$statement->execute(array($objectID));
-		}
-		WCF::getDB()->commitTransaction();
+	public function update($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array()) {
+		$this->getSearchIndexManager()->update($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID, $metaData, $additionalData);
 	}
 	
 	/**
-	 * Resets the search index.
-	 * 
-	 * @param	string		$objectType
+	 * @see	\wcf\system\search\ISearchIndexManager::delete()
 	 */
-	public function reset($objectType) {
-		$sql = "TRUNCATE TABLE " . self::getTableName($objectType);
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute();
+	public function delete($objectType, array $objectIDs) {
+		$this->getSearchIndexManager()->delete($objectType, $objectIDs);
 	}
 	
 	/**
-	 * Creates the search index tables for all registered, searchable object types.
+	 * @see	\wcf\system\search\ISearchIndexManager::reset()
 	 */
-	public static function createSearchIndexTables() {
-		// get definition id
-		$sql = "SELECT	definitionID
-			FROM	wcf".WCF_N."_object_type_definition
-			WHERE	definitionName = ?";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute(array('com.woltlab.wcf.searchableObjectType'));
-		$row = $statement->fetchArray();
-		
-		$objectTypeList = new ObjectTypeList();
-		$objectTypeList->getConditionBuilder()->add("object_type.definitionID = ?", array($row['definitionID']));
-		$objectTypeList->readObjects();
-		
-		foreach ($objectTypeList as $objectType) {
-			self::createSearchIndexTable($objectType);
-		}
+	public function reset($objectType) {
+		$this->getSearchIndexManager()->reset($objectType);
 	}
 	
 	/**
-	 * Creates the search index table for given object type. Returns true if the
-	 * table was created, otherwise false.
-	 * 
-	 * @param	\wcf\data\object\type\ObjectType	$objectType
-	 * @return	boolean
+	 * @see	\wcf\system\search\ISearchIndexManager::createSearchIndices()
 	 */
-	protected static function createSearchIndexTable(ObjectType $objectType) {
-		$tableName = self::getTableName($objectType);
-		
-		// check if table already exists
-		$sql = "SELECT	COUNT(*) AS count
-			FROM	wcf".WCF_N."_package_installation_sql_log
-			WHERE	sqlTable = ?";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute(array($tableName));
-		$row = $statement->fetchArray();
-		if ($row['count']) {
-			// table already exists
-			return false;
-		}
-		
-		$columns = array(
-			array('name' => 'objectID', 'data' => array('length' => 10, 'notNull' => true, 'type' => 'int')),
-			array('name' => 'subject', 'data' => array('default' => '', 'length' => 255, 'notNull' => true, 'type' => 'varchar')),
-			array('name' => 'message', 'data' => array('type' => 'mediumtext')),
-			array('name' => 'metaData', 'data' => array('type' => 'mediumtext')),
-			array('name' => 'time', 'data' => array('default' => 0, 'length' => 10, 'notNull' => true, 'type' => 'int')),
-			array('name' => 'userID', 'data' => array('default' => '', 'length' => 10, 'type' => 'int')),
-			array('name' => 'username', 'data' => array('default' => '', 'length' => 255,'notNull' => true, 'type' => 'varchar')),
-			array('name' => 'languageID', 'data' => array('default' => 0, 'length' => 10, 'notNull' => true, 'type' => 'int'))
-		);
-		
-		$indices = array(
-			array('name' => 'objectAndLanguage', 'data' => array('columns' => 'objectID, languageID', 'type' => 'UNIQUE')),
-			array('name' => 'fulltextIndex', 'data' => array('columns' => 'subject, message, metaData', 'type' => 'FULLTEXT')),
-			array('name' => 'fulltextIndexSubjectOnly', 'data' => array('columns' => 'subject', 'type' => 'FULLTEXT')),
-			array('name' => 'language', 'data' => array('columns' => 'languageID', 'type' => 'KEY')),
-			array('name' => 'user', 'data' => array('columns' => 'userID, time', 'type'=> 'KEY'))
-		);
-		
-		WCF::getDB()->getEditor()->createTable($tableName, $columns, $indices);
-		
-		// add comment
-		$sql = "ALTER TABLE	".$tableName."
-			COMMENT		= ?";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute(array(' Search index for ' . $objectType->objectType));
-		
-		// log table
-		$sql = "INSERT INTO	wcf".WCF_N."_package_installation_sql_log
-					(packageID, sqlTable)
-			VALUES		(?, ?)";
-		$statement = WCF::getDB()->prepareStatement($sql);
-		$statement->execute(array(
-			$objectType->packageID,
-			$tableName
-		));
-		
-		return true;
+	public function createSearchIndices() {
+		$this->getSearchIndexManager()->createSearchIndices();
 	}
 	
 	/**
diff --git a/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchEngine.class.php b/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchEngine.class.php
new file mode 100644
index 0000000000..6c15b3e6dd
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchEngine.class.php
@@ -0,0 +1,244 @@
+<?php
+namespace wcf\system\search\mysql;
+use wcf\system\database\util\PreparedStatementConditionBuilder;
+use wcf\system\database\DatabaseException;
+use wcf\system\exception\SystemException;
+use wcf\system\search\AbstractSearchEngine;
+use wcf\system\search\SearchIndexManager;
+use wcf\system\WCF;
+use wcf\util\StringUtil;
+use wcf\system\search\SearchEngine;
+
+/**
+ * Search engine using MySQL's FULLTEXT index.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+class MysqlSearchEngine extends AbstractSearchEngine {
+	/**
+	 * MySQL's minimum word length for fulltext indices
+	 * @var	integer
+	 */
+	protected static $ftMinWordLen = null;
+	
+	/**
+	 * @see	\wcf\system\search\ISearchEngine::search()
+	 */
+	public function search($q, array $objectTypes, $subjectOnly = false, PreparedStatementConditionBuilder $searchIndexCondition = null, array $additionalConditions = array(), $orderBy = 'time DESC', $limit = 1000) {
+		// handle sql types
+		$fulltextCondition = null;
+		$relevanceCalc = '';
+		if (!empty($q)) {
+			$q = $this->parseSearchQuery($q);
+			
+			$fulltextCondition = new PreparedStatementConditionBuilder(false);
+			switch (WCF::getDB()->getDBType()) {
+				case 'wcf\system\database\MySQLDatabase':
+					$fulltextCondition->add("MATCH (subject".(!$subjectOnly ? ', message, metaData' : '').") AGAINST (? IN BOOLEAN MODE)", array($q));
+				break;
+				
+				case 'wcf\system\database\PostgreSQLDatabase':
+					// replace * with :*
+					$q = str_replace('*', ':*', $q);
+					
+					$fulltextCondition->add("fulltextIndex".($subjectOnly ? "SubjectOnly" : '')." @@ to_tsquery(?)", array($q));
+				break;
+				
+				default:
+					throw new SystemException("your database type doesn't support fulltext search");
+				break;
+			}
+			
+			if ($orderBy == 'relevance ASC' || $orderBy == 'relevance DESC') {
+				switch (WCF::getDB()->getDBType()) {
+					case 'wcf\system\database\MySQLDatabase':
+						$relevanceCalc = "MATCH (subject".(!$subjectOnly ? ', message, metaData' : '').") AGAINST ('".escapeString($q)."') + (5 / (1 + POW(LN(1 + (".TIME_NOW." - time) / 2592000), 2))) AS relevance";
+					break;
+					
+					case 'wcf\system\database\PostgreSQLDatabase':
+						$relevanceCalc = "ts_rank_cd(fulltextIndex".($subjectOnly ? "SubjectOnly" : '').", '".escapeString($q)."') AS relevance";
+					break;
+				}
+			}
+		}
+		
+		// build search query
+		$sql = '';
+		$parameters = array();
+		foreach ($objectTypes as $objectTypeName) {
+			$objectType = SearchEngine::getInstance()->getObjectType($objectTypeName);
+			if (!empty($sql)) $sql .= "\nUNION\n";
+			$additionalConditionsConditionBuilder = (isset($additionalConditions[$objectTypeName]) ? $additionalConditions[$objectTypeName] : null);
+			if (($specialSQL = $objectType->getSpecialSQLQuery($fulltextCondition, $searchIndexCondition, $additionalConditionsConditionBuilder, $orderBy))) {
+				$sql .= "(".$specialSQL.")";
+			}
+			else {
+				$sql .= "(
+						SELECT		".$objectType->getIDFieldName()." AS objectID,
+								".$objectType->getSubjectFieldName()." AS subject,
+								".$objectType->getTimeFieldName()." AS time,
+								".$objectType->getUsernameFieldName()." AS username,
+								'".$objectTypeName."' AS objectType
+								".($relevanceCalc ? ',search_index.relevance' : '')."
+						FROM		".$objectType->getTableName()."
+						INNER JOIN	(
+									SELECT		objectID
+											".($relevanceCalc ? ','.$relevanceCalc : '')."
+									FROM		".SearchIndexManager::getTableName($objectTypeName)."
+									WHERE		".($fulltextCondition !== null ? $fulltextCondition : '')."
+											".(($searchIndexCondition !== null && $searchIndexCondition->__toString()) ? ($fulltextCondition !== null ? "AND " : '').$searchIndexCondition : '')."
+									".(!empty($orderBy) && $fulltextCondition === null ? 'ORDER BY '.$orderBy : '')."
+									LIMIT		1000
+								) search_index
+						ON		(".$objectType->getIDFieldName()." = search_index.objectID)
+						".$objectType->getJoins()."
+						".(isset($additionalConditions[$objectTypeName]) ? $additionalConditions[$objectTypeName] : '')."
+					)";
+			}
+			
+			if ($fulltextCondition !== null) $parameters = array_merge($parameters, $fulltextCondition->getParameters());
+			if ($searchIndexCondition !== null) $parameters = array_merge($parameters, $searchIndexCondition->getParameters());
+			if (isset($additionalConditions[$objectTypeName])) $parameters = array_merge($parameters, $additionalConditions[$objectTypeName]->getParameters());
+		}
+		if (empty($sql)) {
+			throw new SystemException('no object types given');
+		}
+		
+		if (!empty($orderBy)) {
+			$sql .= " ORDER BY " . $orderBy;
+		}
+		
+		// send search query
+		$messages = array();
+		$statement = WCF::getDB()->prepareStatement($sql, $limit);
+		$statement->execute($parameters);
+		while ($row = $statement->fetchArray()) {
+			$messages[] = array(
+				'objectID' => $row['objectID'],
+				'objectType' => $row['objectType']
+			);
+		}
+		
+		return $messages;
+	}
+	
+	/**
+	 * Manipulates the search term (< and > used as quotation marks):
+	 * 
+	 * - <test foo> becomes <+test* +foo*>
+	 * - <test -foo bar> becomes <+test* -foo* +bar*>
+	 * - <test "foo bar"> becomes <+test* +"foo bar">
+	 * 
+	 * @see	http://dev.mysql.com/doc/refman/5.5/en/fulltext-boolean.html
+	 * 
+	 * @param	string		$query
+	 */
+	protected function parseSearchQuery($query) {
+		$query = StringUtil::trim($query);
+		
+		// expand search terms with a * unless they're encapsulated with quotes
+		$inQuotes = false;
+		$previousChar = $tmp = '';
+		$controlCharacterOrSpace = false;
+		$chars = array('+', '-', '*');
+		$ftMinWordLen = self::getFulltextMinimumWordLength();
+		for ($i = 0, $length = mb_strlen($query); $i < $length; $i++) {
+			$char = mb_substr($query, $i, 1);
+			
+			if ($inQuotes) {
+				if ($char == '"') {
+					$inQuotes = false;
+				}
+			}
+			else {
+				if ($char == '"') {
+					$inQuotes = true;
+				}
+				else {
+					if ($char == ' ' && !$controlCharacterOrSpace) {
+						$controlCharacterOrSpace = true;
+						$tmp .= '*';
+					}
+					else if (in_array($char, $chars)) {
+						$controlCharacterOrSpace = true;
+					}
+					else {
+						$controlCharacterOrSpace = false;
+					}
+				}
+			}
+			
+			/*
+			 * prepend a plus sign (logical AND) if ALL these conditions are given:
+			 *
+			 * 1) previous character:
+			 *   - is empty (start of string)
+			 *   - is a space (MySQL uses spaces to separate words)
+			 *
+			 * 2) not within quotation marks
+			 *
+			 * 3) current char:
+			 *   - is NOT +, - or *
+			 */
+			if (($previousChar == '' || $previousChar == ' ') && !$inQuotes && !in_array($char, $chars)) {
+				// check if the term is shorter than MySQL's ft_min_word_len
+				
+				if ($i + $ftMinWordLen <= $length) {
+					$term = '';// $char;
+					for ($j = $i, $innerLength = $ftMinWordLen + $i; $j < $innerLength; $j++) {
+						$currentChar = mb_substr($query, $j, 1);
+						if ($currentChar == '"' || $currentChar == ' ' || in_array($currentChar, $chars)) {
+							break;
+						}
+						
+						$term .= $currentChar;
+					}
+					
+					if (mb_strlen($term) == $ftMinWordLen) {
+						$tmp .= '+';
+					}
+				}
+			}
+			
+			$tmp .= $char;
+			$previousChar = $char;
+		}
+		
+		// handle last char
+		if (!$inQuotes && !$controlCharacterOrSpace) {
+			$tmp .= '*';
+		}
+		
+		return $tmp;
+	}
+	
+	/**
+	 * Returns MySQL's minimum word length for fulltext indices.
+	 * 
+	 * @return	integer
+	 */
+	protected static function getFulltextMinimumWordLength() {
+		if (self::$ftMinWordLen === null) {
+			$sql = "SHOW VARIABLES LIKE ?";
+			$statement = WCF::getDB()->prepareStatement($sql);
+			
+			try {
+				$statement->execute(array('ft_min_word_len'));
+				$row = $statement->fetchArray();
+			}
+			catch (DatabaseException $e) {
+				// fallback if user is disallowed to issue 'SHOW VARIABLES'
+				$row = array('Value' => 4);
+			}
+			
+			self::$ftMinWordLen = $row['Value'];
+		}
+		
+		return self::$ftMinWordLen;
+	}
+}
diff --git a/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchIndexManager.class.php b/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchIndexManager.class.php
new file mode 100644
index 0000000000..016ae2223f
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/search/mysql/MysqlSearchIndexManager.class.php
@@ -0,0 +1,124 @@
+<?php
+namespace wcf\system\search\mysql;
+use wcf\data\object\type\ObjectType;
+use wcf\system\search\AbstractSearchIndexManager;
+use wcf\system\WCF;
+use wcf\system\search\SearchIndexManager;
+
+/**
+ * Search engine using MySQL's FULLTEXT index.
+ * 
+ * @author	Alexander Ebert
+ * @copyright	2001-2014 WoltLab GmbH
+ * @license	GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package	com.woltlab.wcf
+ * @subpackage	system.search
+ * @category	Community Framework
+ */
+class MysqlSearchIndexManager extends AbstractSearchIndexManager {
+	/**
+	 * @see	\wcf\system\search\ISearchIndexManager::add()
+	 */
+	public function add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array()) {
+		if ($languageID === null) $languageID = 0;
+		
+		// save new entry
+		$sql = "REPLACE INTO	" . SearchIndexManager::getTableName($objectType) . "
+					(objectID, subject, message, time, userID, username, languageID, metaData)
+			VALUES		(?, ?, ?, ?, ?, ?, ?, ?)";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute(array($objectID, $subject, $message, $time, $userID, $username, $languageID, $metaData));
+	}
+	
+	/**
+	 * @see	\wcf\system\search\ISearchIndexManager::update()
+	 */
+	public function update($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID = null, $metaData = '', array $additionalData = array()) {
+		// delete existing entry
+		$this->delete($objectType, array($objectID));
+		
+		// save new entry
+		$this->add($objectType, $objectID, $message, $subject, $time, $userID, $username, $languageID, $metaData, $additionalData);
+	}
+	
+	/**
+	 * @see	\wcf\system\search\ISearchIndexManager::delete()
+	 */
+	public function delete($objectType, array $objectIDs) {
+		$sql = "DELETE FROM	" . SearchIndexManager::getTableName($objectType) . "
+			WHERE		objectID = ?";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		WCF::getDB()->beginTransaction();
+		foreach ($objectIDs as $objectID) {
+			$statement->execute(array($objectID));
+		}
+		WCF::getDB()->commitTransaction();
+	}
+	
+	/**
+	 * @see	\wcf\system\search\ISearchIndexManager::reset()
+	 */
+	public function reset($objectType) {
+		$sql = "TRUNCATE TABLE " . SearchIndexManager::getTableName($objectType);
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute();
+	}
+	
+	/**
+	 * @see	\wcf\system\search\AbstractSearchIndexManager::createSearchIndex()
+	 */
+	protected function createSearchIndex(ObjectType $objectType) {
+		$tableName = SearchIndexManager::getTableName($objectType);
+		
+		// check if table already exists
+		$sql = "SELECT	COUNT(*) AS count
+			FROM	wcf".WCF_N."_package_installation_sql_log
+			WHERE	sqlTable = ?";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute(array($tableName));
+		$row = $statement->fetchArray();
+		if ($row['count']) {
+			// table already exists
+			return false;
+		}
+		
+		$columns = array(
+			array('name' => 'objectID', 'data' => array('length' => 10, 'notNull' => true, 'type' => 'int')),
+			array('name' => 'subject', 'data' => array('default' => '', 'length' => 255, 'notNull' => true, 'type' => 'varchar')),
+			array('name' => 'message', 'data' => array('type' => 'mediumtext')),
+			array('name' => 'metaData', 'data' => array('type' => 'mediumtext')),
+			array('name' => 'time', 'data' => array('default' => 0, 'length' => 10, 'notNull' => true, 'type' => 'int')),
+			array('name' => 'userID', 'data' => array('default' => '', 'length' => 10, 'type' => 'int')),
+			array('name' => 'username', 'data' => array('default' => '', 'length' => 255,'notNull' => true, 'type' => 'varchar')),
+			array('name' => 'languageID', 'data' => array('default' => 0, 'length' => 10, 'notNull' => true, 'type' => 'int'))
+		);
+		
+		$indices = array(
+			array('name' => 'objectAndLanguage', 'data' => array('columns' => 'objectID, languageID', 'type' => 'UNIQUE')),
+			array('name' => 'fulltextIndex', 'data' => array('columns' => 'subject, message, metaData', 'type' => 'FULLTEXT')),
+			array('name' => 'fulltextIndexSubjectOnly', 'data' => array('columns' => 'subject', 'type' => 'FULLTEXT')),
+			array('name' => 'language', 'data' => array('columns' => 'languageID', 'type' => 'KEY')),
+			array('name' => 'user', 'data' => array('columns' => 'userID, time', 'type'=> 'KEY'))
+		);
+		
+		WCF::getDB()->getEditor()->createTable($tableName, $columns, $indices);
+		
+		// add comment
+		$sql = "ALTER TABLE	".$tableName."
+			COMMENT		= ?";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute(array(' Search index for ' . $objectType->objectType));
+		
+		// log table
+		$sql = "INSERT INTO	wcf".WCF_N."_package_installation_sql_log
+					(packageID, sqlTable)
+			VALUES		(?, ?)";
+		$statement = WCF::getDB()->prepareStatement($sql);
+		$statement->execute(array(
+			$objectType->packageID,
+			$tableName
+		));
+		
+		return true;
+	}
+}
diff --git a/wcfsetup/install/files/options.inc.php b/wcfsetup/install/files/options.inc.php
index 3f42323f7e..b224f34812 100644
--- a/wcfsetup/install/files/options.inc.php
+++ b/wcfsetup/install/files/options.inc.php
@@ -36,3 +36,4 @@ define('ENABLE_BENCHMARK', 0);
 define('EXTERNAL_LINK_TARGET_BLANK', 0);
 define('URL_LEGACY_MODE', 0);
 define('URL_TO_LOWERCASE', 1);
+define('SEARCH_ENGINE', 'mysql');
-- 
2.20.1