SELECTing comman seperated values from db ?

[Vaupell]

want to make some modifications in a CP
where the admin selects / adds which usergroups is
able to moderator this mod.

now my question is

Do i make my table as a interger/double etc ? to store values like 5,6,7 etc

Okey then, when SELECTING the values from the db
how do i seperate them, ?

say in my mod (end user area)
i would add a botton like this..

PHP Code:

$checkID = $vbulletin->db->query("SELECT userGUID FROM " . TABLE_PREFIX . "sometable");

/*
Seperate comma values ? 
*/

<if condition="is_member_of($bbuserinfo, $checkID[userGUID])">
Botton/info or other stuff
</if>