Very strang Selecting DB problem

[KingWylim]

Here's the code:

mysql_select_db($database_trustinme, $trustinme) or die("Error connecting to Database: ".mysql_error());
$selectSQL = "SELECT cat_name FROM category WHERE cat_id = '$cat_father_id'";
$Result1 = mysql_query($selectSQL, $trustinme) or die("Error executing query: ".mysql_error());

Here's the error I keep getting can't figure out why:
Warning: mysql_select_db(): supplied argument is not a valid MySQL-Link resource in /home/content/s/h/u/shunobies/html/admin/includes/functions.php on line 11
Error connecting to Database:

Any help is greatly appreciated.
Thank you.

[NogDog]

It means that $trustinme does not hold the value of a valid mysql_connect() resource ID. Either your mysql_connect() did not succeed, or you assigned its result to some other variable (maybe a variable spelling mistake?).