Fatal error: Call to a member function on a non-object

[CrossMediaGroup]

Can anyone help me with the following error:

Fatal error: Call to a member function on a non-object
in /home/username/public_html/business/admin/modules/topics.php on line 22

I think it occurs here:

20: global $prefix, $db;
21: $aid = substr("$aid", 0,25);
22: $row = $db->sql_fetchrow($db->sql_query("SELECT radmintopic, 
      radminsuper FROM ".$prefix . "_authors WHERE aid='$aid'"));
23: if (($row['radmintopic'] == 1) OR ($row['radminsuper'] == 1)) {

[idx]

Without really seeing the code, my guess is that the $db object was never created.

-r

[CrossMediaGroup]

A case file had some code that was tempered with. I fixed it. Thanks.