很遗憾，您无法执行meta_query 使用LIKE 比较meta_key 使用时的值WP_Query. 我一直在走这条路。。。

相反，如果您想在自定义表中维护与post meta类似的状态关系，而不是用户meta和/或meta，那么您还有几个其他选项。

选项1不需要修改元模式的使用wpdb 类来执行自定义查询示例：

//when a user likes a post...
$current_user_id = get_current_user_id();
add_post_meta($current_user_id, "like_status_{$current_user_id}", 1, false);

//later in the request...
global $wpdb;

$results = $wpdb->get_results(
    "
    SELECT meta_key 
    FROM {$wpdb->prefix}postmeta 
    WHERE meta_key 
    LIKE \'like_status_%\'
    ",
    ARRAY_N
);

$results = array_map(function($value){

    return (int) str_replace(\'like_status_\', \'\', $value[0]);

}, $results);

array_walk($results, function($notify_user_id, $key){

    //apply to all users except the user who just liked the post
    if ( $notify_user_id !== $current_user_id ) {
        //notify logic here...           
    }

});

注：如果您愿意，可以进一步简化逻辑

选项2要求您更改元架构，因为元值允许您使用WP_Query 随着meta_querylike_status_{user_id} 对于一些通用的东西，例如like_status 或liked_by_user_id 而不是存储1 相反，您将用户id存储为值。

//when a user likes a post...
$current_user_id = get_current_user_id();
add_post_meta($current_user_id, "liked_by_user_id", $current_user_id, false);

//later in the request
$args = array(
    \'post_type\'  => \'post\', //or a post type of your choosing
    \'posts_per_page\' => -1,
    \'meta_query\' => array(
        array(
            \'key\' => \'liked_by_user_id\',
            \'value\' => 0,
            \'type\' => \'numeric\'
            \'compare\' => \'>\'
        )
    )
);

$query = new WP_Query($args);   

array_walk($query->posts, function($post, $key){

    $user_ids = get_post_meta($post->ID, \'liked_by_user_id\');

    array_walk($user_ids, function($notify_user_id, $key){
        
        //notify all users except the user who just like the post
        if ( $notify_user_id !== $current_user_id ) {
                
            //notify logic here...
            //get user e.g. $user = get_user_by(\'id\', $notify_user_id);
            
        }

    });

});