static function unassignedProductGroups($_slmaster_id = '')
{
if (empty($_slmaster_id)) {
$current_prod_groups = array();
} else {
$cc = new ConstraintChain();
$cc->add(new Constraint('slmaster_id', '=', $_slmaster_id));
$sldiscount = new SLDiscount();
$sldiscount->identifierField = 'prod_group_id';
$sldiscount->orderby = 'prod_group_id';
$current_prod_groups = $sldiscount->getAll($cc);
}
$cc = new ConstraintChain();
$prodgroup = new STProductgroup();
if (count($current_prod_groups) > 0) {
$cc->add(new Constraint($prodgroup->idField, 'not in', '(' . implode(',', $current_prod_groups) . ')'));
}
return $prodgroup->getAll($cc);
}
