Revoke DB rights on install only if the db is newly created

lib/setup.php

@@ -319,9 +319,11 @@ class OC_Setup {
 				$entry.='Offending command was: '.$query.'<br />';
 				echo($entry);
 			}
+			else {
+				$query = "REVOKE ALL PRIVILEGES ON DATABASE \"$e_name\" FROM PUBLIC";
+				$result = pg_query($connection, $query);
+			}
 		}
-		$query = "REVOKE ALL PRIVILEGES ON DATABASE \"$e_name\" FROM PUBLIC";
-		$result = pg_query($connection, $query);
 	}
 
 	private static function pg_createDBUser($name, $password, $connection) {