php多维数组选择框mysql插入

Question

我有这个HTML代码：

<select id="users_list" data-placeholder="Choose a user..." multiple name="users_list[]">

        <?php while($users = mysql_fetch_array($all_users)){ ?>

                        <option value='<?php echo serialize(array($users['id_user'], $users['name'], $users['image_url'])); ?>' <?php if($users['id_user'] == $_SESSION['user_id']) echo "disabled"; ?>><?php echo $users['name']; ?></option>

        <?php } ?>

</select>

如何将值插入mysql db？ 要清楚我写了这个PHP代码：

$users_list = $_POST['users_list'];
foreach($users_list as $user)
{
    $user = unserialize($user);
    foreach($user as $info){
    }
        $query = "INSERT INTO messages (from_user, to_user, text, sender_name, sender_image, recipant_name, recipant_image, date) VALUES ('$uid', '$user', '$message', '$uname', '$uimage', '$time')";
    $insert = mysql_query($query);
    $mid = mysql_insert_id();
    update_user_notf($user, $uid, $uname, $uimage, $mid, "message");
}

那不对，我需要另一个代码来执行操作。请帮忙。