Deleted Comments Stick Around

Hmm tough problem. Heres hook_nodeapi and hook_user

/**
 * Implementation of hook_nodeapi().
 */
function activity_nodeapi(&$node, $op, $a3 = NULL, $a4 = NULL) {
  if ($op == 'delete') {
    // Remove all activity records for this node.
    db_query("DELETE m, at, aa, a FROM {activity} a
              LEFT JOIN {activity_access} aa ON aa.aid = a.aid
              INNER JOIN {activity_targets} at ON at.aid = a.aid
              INNER JOIN {activity_messages} m ON m.amid = at.amid
              WHERE a.nid = %d", $node->nid);
  }
}

/**
 * Implementation of hook_user().
 */
function activity_user($op, &$edit, &$account, $category = NULL) {
  if ($op == 'delete') {
    // Remove all activity records for this user.
    db_query("DELETE m, at, aa, a FROM {activity} a
              LEFT JOIN {activity_access} aa ON aa.aid = a.aid
              INNER JOIN {activity_targets} at ON at.aid = a.aid
              INNER JOIN {activity_messages} m ON m.amid = at.amid
              WHERE a.uid = %d", $account->uid);
  }
}

In both cases we had a foriegn key to use (nid and uid). We keep uid so we can know the 'Creator' of the Activity and we keep the nid so we can make sure a user has access to view the node. I cannot imagine a case where storing other 'keys' would be a.) doable and b.) desirable

I would suggest, when deleting activities that you use the url activity/$aid/delete. There is a View handler to create a link to this and a default admin Activities View.

This feels like a Cannot Fix for design reasons...

Ok marking as by design

#609888: Add a generic oid column as a foreign key