Somethign else to think about as well, look at this slight modification:
select pk from a left join b using (pk);
Now, it's not likely this is a valid query for your table structure, but, in this instance, a.pk and b.pk are not necessarily the same. b.pk could potentially be NULL while a.pk was not
-- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
