diff --git a/lib/private/db.php b/lib/private/db.php
index f6854e3e16..82affe293e 100644
--- a/lib/private/db.php
+++ b/lib/private/db.php
@@ -307,21 +307,32 @@ class OC_DB {
 	/**
 	 * update the database schema
 	 * @param string $file file to read structure from
-	 * @param bool $simulate whether to simulate the upgrade on separate tables
 	 * @throws Exception
 	 * @return string|boolean
 	 */
-	public static function updateDbFromStructure($file, $simulate = false) {
+	public static function updateDbFromStructure($file) {
 		$schemaManager = self::getMDB2SchemaManager();
 		try {
-			$result = $schemaManager->updateDbFromStructure($file, false, $simulate);
+			$result = $schemaManager->updateDbFromStructure($file);
 		} catch (Exception $e) {
-			if ($simulate) {
-				OC_Log::write('core', 'Database structure update simulation failed ('.$e.')', OC_Log::FATAL);
-			}
-			else {
-				OC_Log::write('core', 'Failed to update database structure ('.$e.')', OC_Log::FATAL);
-			}
+			OC_Log::write('core', 'Failed to update database structure ('.$e.')', OC_Log::FATAL);
+			throw $e;
+		}
+		return $result;
+	}
+
+	/**
+	 * simulate the database schema update
+	 * @param string $file file to read structure from
+	 * @throws Exception
+	 * @return string|boolean
+	 */
+	public static function simulateUpdateDbFromStructure($file) {
+		$schemaManager = self::getMDB2SchemaManager();
+		try {
+			$result = $schemaManager->simulateUpdateDbFromStructure($file);
+		} catch (Exception $e) {
+			OC_Log::write('core', 'Simulated database structure update failed ('.$e.')', OC_Log::FATAL);
 			throw $e;
 		}
 		return $result;
diff --git a/lib/private/db/mdb2schemamanager.php b/lib/private/db/mdb2schemamanager.php
index 397aaf3608..734ba18d1a 100644
--- a/lib/private/db/mdb2schemamanager.php
+++ b/lib/private/db/mdb2schemamanager.php
@@ -73,33 +73,46 @@ class MDB2SchemaManager {
 		}
 	}
 
+	/**
+	 * Reads database schema from file
+	 *
+	 * @param string $file file to read from
+	 */
+	private function readSchemaFromFile($file) {
+		$platform = $this->conn->getDatabasePlatform();
+		$schemaReader = new MDB2SchemaReader(\OC_Config::getObject(), $platform);
+		return $schemaReader->loadSchemaFromFile($file);
+	}
+
 	/**
 	 * update the database scheme
 	 * @param string $file file to read structure from
 	 * @param bool $generateSql only return the sql needed for the upgrade
-	 * @param bool $simulate whether to simulate on separate tables instead of the real onces
 	 * @return string|boolean
 	 */
-	public function updateDbFromStructure($file, $generateSql = false, $simulate = false) {
-
-		$platform = $this->conn->getDatabasePlatform();
-		$schemaReader = new MDB2SchemaReader(\OC_Config::getObject(), $platform);
-		$toSchema = $schemaReader->loadSchemaFromFile($file);
+	public function updateDbFromStructure($file, $generateSql = false) {
+		$toSchema = $this->readSchemaFromFile($file);
 		$migrator = $this->getMigrator();
 
 		if ($generateSql) {
 			return $migrator->generateChangeScript($toSchema);
 		} else {
-			if ($simulate) {
-				$migrator->checkMigrate($toSchema);
-			}
-			else {
-				$migrator->migrate($toSchema);
-			}
+			$migrator->migrate($toSchema);
 			return true;
 		}
 	}
 
+	/**
+	 * update the database scheme
+	 * @param string $file file to read structure from
+	 * @return string|boolean
+	 */
+	public function simulateUpdateDbFromStructure($file) {
+		$toSchema = $this->readSchemaFromFile($file);
+		$migrator = $this->getMigrator()->checkMigrate($toSchema);
+		return true;
+	}
+
 	/**
 	 * @param \Doctrine\DBAL\Schema\Schema $schema
 	 * @return string
diff --git a/lib/private/updater.php b/lib/private/updater.php
index 1c363123e1..106970c412 100644
--- a/lib/private/updater.php
+++ b/lib/private/updater.php
@@ -130,7 +130,7 @@ class Updater extends BasicEmitter {
 		// simulate DB upgrade
 		try {
 			// simulate core DB upgrade
-			\OC_DB::updateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml', true);
+			\OC_DB::simulateUpdateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml');
 
 			// simulate apps DB upgrade
 			$version = \OC_Util::getVersion();
@@ -139,7 +139,7 @@ class Updater extends BasicEmitter {
 				$info = \OC_App::getAppInfo($appId);
 				if (\OC_App::isAppCompatible($version, $info) && \OC_App::shouldUpgrade($appId)) {
 					if (file_exists(\OC_App::getAppPath($appId) . '/appinfo/database.xml')) {
-						\OC_DB::updateDbFromStructure(\OC_App::getAppPath($appId) . '/appinfo/database.xml', true);
+						\OC_DB::simulateUpdateDbFromStructure(\OC_App::getAppPath($appId) . '/appinfo/database.xml');
 					}
 				}
 			}