덧글 ip를 표시하기 위해 스레드 답변을 참고하여 다음과 같이 수정했는데 덧글이 아예 나오질 않습니다. 

어디를 수정해야 하는지요?

KBCommentList.class.php 파일의 add() 메소드 부분

public function add($parent_uid, $user_uid, $user_display, $content, $password=''){
        global $wpdb;
        $content_uid = $this->content_uid;
        $parent_uid = intval($parent_uid);
        $user_uid = intval($user_uid);
        $user_display = addslashes(kboard_xssfilter(kboard_htmlclear(trim($user_display))));
        $content = addslashes(trim($content));
        $password = addslashes(kboard_xssfilter(kboard_htmlclear(trim($password))));
        $created = current_time('YmdHis');
        $ip = $_SERVER['REMOTE_ADDR'];
        
        $wpdb->query("INSERT INTO `{$wpdb->prefix}kboard_comments` (`content_uid`, `parent_uid`, `user_uid`, `user_display`, `content`, `created`, `password`, 'ip') VALUE ('$content_uid', '$parent_uid', '$user_uid', '$user_display', '$content', '$created', '$password', 'ip')");

index.php

function kboard_comments_activation_execute(){
    global $wpdb;
    
    $wpdb->query("CREATE TABLE IF NOT EXISTS `{$wpdb->prefix}kboard_comments` (
        `uid` bigint(20) unsigned NOT NULL auto_increment,
        `content_uid` bigint(20) unsigned NOT NULL,
        `parent_uid` bigint(20) unsigned default NULL,
        `user_uid` bigint(20) unsigned default NULL,
        `user_display` varchar(127) default NULL,
        `content` longtext NOT NULL,
        `created` char(14) NOT NULL,
        `password` varchar(127) default NULL,
        `ip` varchar(127) default NULL,

list.php

<!-- 댓글 입력 폼 시작 -->
        <form id="kboard_comments_form" method="post" action="<?php echo $commentURL->getInsertURL()?>" onsubmit="return kboard_comments_execute(this);">
            <input type="hidden" name="content_uid" value="<?php echo $commentList->content_uid?>">
            <input type="hidden" name="member_uid" value="<?php echo $member_uid?>">
            <div class="kboard-comments-form">        
                <div class="comments-ip">
                    <input type="hidden" id="comments_ip" name="ip" value="<?php echo $commentList->ip?>">
                </div>
                <?php if(is_user_logged_in()):?>
                <input type="hidden" name="member_display" value="<?php echo $userdata->display_name?>">

list-template.php

<div class="comments-list-username" itemprop="author"><?php echo $comment->user_display?></div>
            <div class="comments-list-create" itemprop="dateCreated"><?php echo date("Y-m-d H:i", strtotime($comment->created))?></div>
            <div class="comments-list-ip" itemprop="ip"><?php echo $comment->ip?></div>

감사합니다.

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