我在我的query\\u帖子中有以下查询，希望向其中添加order by。Order by将位于另一个自定义字段上，并按desc Order排序。

这是我现有的查询。

//show all active posts for this taxonomy
 query_posts( array(
   \'post_type\' => APP_POST_TYPE,
   \'post_status\' => \'publish\',
   APP_CUSTOM_TAX => $term->slug,
   \'ignore_sticky_posts\' => 1,
   \'orderby\' => \'date\', //Instead of this, i want to use custom field like \'votes\',\'date\'
   \'meta_query\' => array(
       \'relation\' => \'OR\',
             array(
                \'key\' => \'offer_type\',
                \'compare\' => \'NOT EXISTS\',
              ),
              array(
                \'key\' => \'offer_type\',
                \'value\' => \'top\',
                \'compare\' => \'!=\',
              )
      ))
);