如何将最后一行更改为order by rand？现在是按我的woocommerce产品的日期排序。

INNER JOIN $wpdb->postmeta AS mt1 ON (posts.ID = mt1.post_id)
    WHERE
        posts.post_status = \'publish\'
        AND  (mt1.meta_key = \'_sale_price_dates_to\' AND mt1.meta_value >= ".time().")

        GROUP BY posts.ID
        **ORDER BY posts.post_date DESC";**