Попробуйте использовать следующий код фильтра
if (isset($_GET['type']))
{
$element['type'] = 1;
if (!isset($_GET['q']))
{
$element['prefix'] = ' and ';
}
else
{
$element['prefix'] = ' ( ';
}
$element['property_id'] = to_int($_GET['type']);
$element['if'] = '=';
$element['value'] = '1';
$element['sufix']='';
$property['select'][] = $element;
}
if (isset($_GET['q']))
{
$element['type'] = 1;
$element['property_id'] = 21;
$element['if'] = '=';
$element['value'] = to_int($_GET['q']);
$element['sufix']='';
$property['select'][] = $element;
if (isset($_GET['type'])
{
$element['prefix'] = ' or ';
$having_count = ' HAVING COUNT (information_propertys_items_table.information_propertys_items_id) = 2';
$element['sufix']=') GROUP BY information_items_table.information_items_id ' . $having_count;
}
else
{
$element['prefix'] = ' and ';
$element['sufix']= '';
}
$property['select'][] = $element;
}