php - 在PHP的留言板上向留言添加注释

我有一个类似于Facebook的简单留言板页面。用户发布消息，用户可以对此消息发表评论。每条消息都张贴在页面上，并且在每条消息下方都有一个地方可以对该消息提交评论。在我的数据库中，有用于用户，消息和注释的表。

我的问题是：我如何知道我要评论的特定消息，以便将它与相应的message_id正确传递到MySQL数据库？

$comm = "INSERT INTO comments(user_id, message_id, comment, created_at, updated_at)
                    SELECT '{$_SESSION['id']}', '{$_SESSION['messages.id']}', '{$_SESSION['comment']}', NOW(), NOW()
                    FROM messages";

编辑：

$query = "SELECT users.first_name AS first_name, users.last_name AS last_name, messages.id AS mess_id,
                    messages.message AS message, DATE_FORMAT(messages.created_at, '%M %e %Y') AS time
            FROM users
            LEFT JOIN messages
            ON  users.id = messages.user_id
            ORDER BY time DESC";

            $results = fetch($query);
            foreach ($results as $row) {
                $_SESSION['messages.id'] = $row['mess_id'];
                echo
                    "<div class='post'>".
                    $row['first_name']. " ". $row['last_name']. " - ". $row['time']. "<br>".
                        "<p class='mess_content'>". $row['message']. "</p>
                    </div><br>
                    <div class='posted_comm'>";
                        $query = "SELECT users.first_name AS first_name, users.last_name AS last_name,
                                    comments.message_id, DATE_FORMAT(comments.created_at, '%M %e %Y') AS time, comments.comment AS comment
                                FROM users
                                LEFT JOIN comments
                                ON  users.id = comments.user_id
                                WHERE comments.message_id = '{$_SESSION['messages.id']}'
                                ORDER BY time ASC";
                        $results1 = fetch($query);
                        foreach ($results1 as $value) {
                            echo
                            "<div class='comments'>".
                                $value['first_name']. " ". $value['last_name']. " - ". $value['time']. "<br>".
                                "<p class='comm_content'>". $value['comment']. "</p>
                            </div><br>";
                        }
                echo "<div class='write_comm'>
                        <form method='post' action='mess_comm.php'>
                            <input type='hidden' name='action' value='post_comm'>
                            Post a comment:<input type='text' name='comm' class='comm'>
                            <input type='submit' value='Post a comment' class='comm_sub'>
                        </form>
                    </div>";

最佳答案

扩展表单，使其包含消息ID作为隐藏字段：

 echo "<div class='write_comm'>
                    <form method='post' action='mess_comm.php'>
                        <input type='hidden' name='action' value='post_comm'>
                        <input type='hidden' name='message_id' value='{$row['mess_id']}'>
                        Post a comment:<input type='text' name='comm' class='comm'>
                        <input type='submit' value='Post a comment' class='comm_sub'>
                    </form>
                </div>";

然后在查询中使用ID：

$comm = "INSERT INTO comments(user_id, message_id, comment, created_at, updated_at)
                VALUES ('{$_SESSION['id']}', '{$_POST['message_id']}', '{$_POST['comm']}', NOW(), NOW())";