打印准备好的查询时，我看到以下字符串：

"SELECT p.ID, COALESCE(w.value,Display_name) value, p.post_title, p.post_date, p.post_content,p.post_author,user_login FROM wp_posts p INNER JOIN wp_users a ON a.ID = p.post_author LEFT JOIN wp_bp_xprofile_data w ON w.user_id = a.ID WHERE post_type = \'reply\' and post_parent = 53592568 and p.ID > 53592614 AND TIMEDIFF( \'2017-12-04 06:14:58\', post_date ) < \'00:00:15\' AND post_content is not null ORDER BY post_date ASC LIMIT 0 , 5"

当我通过SQL客户端运行它时，它似乎返回良好：

但当我试着和wpdb->get_results 或wpdb->query 我的wordpress模板中的函数。

这是我的代码：

global $wpdb;

$reply_id = $_REQUEST["id"];
$postId   = $_REQUEST["post_id"];

$data = date("Y-m-d H:i:sa");
$dataStr = str_replace("am","",str_replace("pm","",$data));

$mysqli_query = "SELECT p.ID, COALESCE(w.value,Display_name) value, p.post_title, p.post_date, p.post_content,p.post_author,user_login ";
$mysqli_query .= " FROM  wp_posts p ";
$mysqli_query .= " INNER JOIN wp_users a ON a.ID = p.post_author ";
$mysqli_query .= " LEFT JOIN wp_bp_xprofile_data w ON w.user_id = a.ID ";
$mysqli_query .= " WHERE post_type = \'reply\' ";
$mysqli_query .= " and post_parent = %d ";
$mysqli_query .= " and p.ID > %d ";
$mysqli_query .= " AND TIMEDIFF(  \'%s\', post_date ) <  \'00:00:15\' ";
$mysqli_query .= " AND post_content is not null ";
$mysqli_query .= " ORDER BY post_date ASC  ";
$mysqli_query .= " LIMIT 0 , 5";

$reply_query = $wpdb->prepare($mysqli_query, $postId, $reply_id, $dataStr);

$results = $wpdb->get_results( $reply_query );
var_dump($results);

这里是什么var_dump 为我显示：

array(0) { }

有人能帮我找出这个代码的错误吗？

非常感谢。

$reply_id = $_REQUEST["id"];
$postId   = $_REQUEST["post_id"];
$data = date("Y-m-d H:i:s");
$mysqli_query = "SELECT p.ID, COALESCE(w.value,a.display_name) value, p.post_title, p.post_date, p.post_content, p.post_author, a.user_login ";
$mysqli_query .= " FROM {$wpdb->prefix}posts p ";
$mysqli_query .= " INNER JOIN {$wpdb->prefix}users a ON a.ID = p.post_author ";
$mysqli_query .= " LEFT JOIN {$wpdb->prefix}bp_xprofile_data w ON w.user_id = a.ID ";
$mysqli_query .= " WHERE p.post_type = \'reply\' ";
$mysqli_query .= " AND p.post_parent = %d ";
$mysqli_query .= " AND p.ID > %d ";
$mysqli_query .= " AND TIMEDIFF(  %s, p.post_date ) <  \'00:00:15\' ";
$mysqli_query .= " AND p.post_content IS NOT NULL ";
$mysqli_query .= " ORDER BY p.post_date ASC  ";
$mysqli_query .= " LIMIT 0 , 5";

$reply_query = $wpdb->prepare($mysqli_query, $postId, $reply_id, $data);

$results = $wpdb->get_results( $reply_query );