It is not possible to run a query link this:

UPDATE t SET id = id + 1 ORDER BY id DESC;

                  EXAMPLE OF USE

UPDATE t SET id = id + 1;

For example, if the table contains 1 and 2 in the id column and 1 is updated to 2 before 2 is updated to 3, an error occurs. To avoid this problem, add an ORDER BY clause to cause the rows with larger id values to be updated before those with smaller values:

UPDATE t SET id = id + 1 ORDER BY id DESC;

It would be nice to have an extra param to specify order:

$db->update($table, $where, $order);