我正在尝试通过查询获取帖子摘要我的代码如下

global $wpdb;
$posts = $wpdb->get_results ("SELECT post_title, post_excerpt 
FROM $wpdb->posts WHERE post_status = \'publish\' AND (post_type = \'post\') 
AND post_content LIKE \'%My Text%\' ORDER BY post_date DESC");

任何帮助