private List<Object> findIdsByParentId(Object parentId, Transaction t) {
String rawWhere = deriveWhereParentIdSql(false);
EbeanServer server = getBeanDescriptor().getEbeanServer();
Query<?> q = server.find(getPropertyType())
.where().raw(rawWhere).query();
bindWhereParendId(q, parentId);
return server.findIds(q, t);
}