$cleanup = \OC_DB::prepare('DELETE FROM `*PREFIX*documents_member` WHERE `member_id` NOT IN(SELECT `member_id` from `*PREFIX*documents_member` WHERE `last_activity`>0)');
$cleanup = \OC_DB::prepare('DELETE FROM `*PREFIX*documents_member` WHERE `last_activity`=0 or `last_activity` is NULL');
$cleanup->execute();
if (version_compare($installedVersion, '0.7', '<=')) {