[Kingly_Krab]

I use this.

SELECT * FROM items WHERE classes & [class bitmask];

Example, items that Berserkers use.

SELECT * FROM items WHERE classes & 32768;

Here's a wiki for you, Nydosa, on bitwise operators.

Operator    Meaning
&           Bitwise AND.
|           Bitwise OR.
^           Bitwise exclusive OR.