我正在努力让我的帖子按radius排序，到目前为止我一直在努力，我一直在使用Steve MArks的以下tut，http://biostall.com/performing-a-radial-search-with-wp_query-in-wordpress

下面是产生错误的代码，错误如下。

function location_posts_where( $where )  
{  
    global $wpdb;
    // Specify the co-ordinates that will form  
    // the centre of our search  
    $lat = \'50.12335\';  
    $lng = \'-1.344453\';  

    $radius = 10; // (in miles)  

    // Append our radius calculation to the WHERE  
    $where .= " AND $wpdb->posts.ID IN (SELECT post_id FROM lat_lng_post WHERE 
         ( 3959 * acos( cos( radians(" . $lat . ") ) 
                        * cos( radians( lat ) ) 
                        * cos( radians( lng ) 
                        - radians(" . $lng . ") ) 
                        + sin( radians(" . $lat . ") ) 
                        * sin( radians( lat ) ) ) ) <= " . $radius . ")";  

    // Return the updated WHERE part of the query  
    return $where;  
}

WordPress database error: [You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near \'IN (SELECT `post_id` FROM `lat_lng_post` WHERE ( 3959 * acos( cos( rad\' at line 1]
SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = \'festival-event\' AND (wp_posts.post_status = \'publish\' OR wp_posts.post_status = \'private\') AND .ID IN (SELECT `post_id` FROM `lat_lng_post` WHERE ( 3959 * acos( cos( radians(50.12335) ) * cos( radians( \'lat\' ) ) * cos( radians( \'lng\' ) - radians(-1.344453) ) + sin( radians(50.12335) ) * sin( radians( \'lat\' ) ) ) ) <= 10) ORDER BY wp_posts.post_date DESC LIMIT 0, 10

我试着像前面的线程所说的那样，对字符串的db部分进行回溯，但这也不起作用。

我的SQL知识不高，但它在我的待办事项列表中，如果有任何帮助，我将不胜感激。