$this->_select = 'cl.`name` as country';
$this->_join = '
    LEFT JOIN `'._DB_PREFIX_.'country_lang` cl ON (cl.`id_country` = a.`id_country` AND cl.`id_lang` = '.(int)$this->context->language->id.')
    LEFT JOIN `'._DB_PREFIX_.'customer` c ON a.id_customer = c.id_customer
        ';
$this->_where = 'AND a.id_customer != 0 '.Shop::addSqlRestriction(Shop::SHARE_CUSTOMER, 'c');

'city' => array('title' => $this->l('City')),

'state' => array('title' => $this->l('State'), 'filter_key' => 'st!name'),

LEFT JOIN `'._DB_PREFIX_.'customer` c ON a.id_customer = c.id_customer

LEFT JOIN `'._DB_PREFIX_.'state` st ON a.id_state = st.id_state