Merge pull request #4799 from owncloud/tune_legacy_cache_webdav_properties_prefixing_master

Concatenate string in SQL instead of PHP

apps/files/appinfo/update.php

@@ -3,17 +3,14 @@
 // fix webdav properties,add namespace in front of the property, update for OC4.5
 $installedVersion=OCP\Config::getAppValue('files', 'installed_version');
 if (version_compare($installedVersion, '1.1.6', '<')) {
-	$query = OC_DB::prepare( 'SELECT `propertyname`, `propertypath`, `userid` FROM `*PREFIX*properties`' );
-	$result = $query->execute();
-	$updateQuery = OC_DB::prepare('UPDATE `*PREFIX*properties`'
-								.' SET `propertyname` = ?'
-								.' WHERE `userid` = ?'
-								.' AND `propertypath` = ?');
-	while( $row = $result->fetchRow()) {
-		if ( $row['propertyname'][0] != '{' ) {
-			$updateQuery->execute(array('{DAV:}' + $row['propertyname'], $row['userid'], $row['propertypath']));
-		}
-	}
+	$concat = OC_DB::getConnection()->getDatabasePlatform()->
+		getConcatExpression( '\'{DAV:}\'', '`propertyname`' );
+	$query = OC_DB::prepare('
+		UPDATE `*PREFIX*properties`
+		SET    `propertyname` = ' . $concat . '
+		WHERE  `propertyname` NOT LIKE \'{%\'
+	');
+	$query->execute();
 }
 
 //update from OC 3