I have a special need, in the Drupal for Facebook modules, to honor a session key that comes from Facebook, instead of the key Drupal normally uses. So far the way I've approached this is to have Drupal use the passed-in session_key, so the sid column of the sessions table is that value. My problem is the the length of these session keys is sometimes longer than the 64 character limit of the sid column. According to Facebook these keys could be 128 characters or even longer. (http://forum.developers.facebook.com/viewtopic.php?id=21931) My first thought is to alter Drupal's sessions table. That is, in my module's .install file I would alter sessions so that the sid column is varchar(256) instead of varchar(64). Is there a performance drawback to this? Is it bad form to alter the table this way? My other options include finding some way to compress the session_key down to 64 chars. Or, create a table that maps longer session_keys to Drupal's sids. Is there any reason to go with one of these options as opposed to altering the table? Thanks in advance, -Dave