Plain 'ol non-Drupal SQL will still work in db_query ... it's just not a best practice since the database API can't retool the SQL to work in any supported environment, and doesn't take advantage of Drupal's SQL injection protections, among other things.
But it still works.
If you're going to use the SQL in a known environment (e.g. a system where these commands are already in use), I'd say just use them as they are for now and gradually convert them over to Drupal standards as new code is developed.
(Of course, if this code is meant to be distributed to other environments, you'll want to put in sweat equity and convert the strings, or write a tool to do so)