ecshop获取商品购买数量

function get_buy_sum($goods_id)
{
$sql = "select sum(goods_number) from " . $GLOBALS['ecs']->table('order_goods') . " AS g ,".$GLOBALS['ecs']->table('order_info') . " AS o WHERE o.order_id=g.order_id and g.goods_id = " . $goods_id . "  and o.order_status=1 "  ;//o.order_status=1 表示确认了的订单才算
    return $GLOBALS['db']->getOne($sql);
}