我在使用准备好的语句列出评论时遇到问题。有什么想法吗？这是我的代码:$fetchComments=$cnx->prepare("SELECTcommentFROMcommentsWHEREvideo_id=?LIMIT1");$fetchComments->bind_param('s',$row['id']);$fetchComments->execute();$fetchComments->store_result();$fetchComments->bind_result($vid_comment);if($fetchComments->num_rows>0){whike($row