投票内容向上或向下显示投票时的HTML代码

Question

每当我点击我的PHP / MySQL / JS投票系统上下投票时，它会显示很长的HTML代码列表。我不知道什么是错误，有些人建议我删除unique_content_id，因为表中有该属性的空白行，我们不知道为什么。我会试一试并在这里发帖。

错误：

http://pastebin.com/b0SQL7X4

vote_process.php文件

if($_POST)
{

    ### connect to mySql
    $sql_con = mysqli_connect($db_host, $db_username, $db_password,$db_name)or die('could not connect to database');

    //get type of vote from client
    $user_vote_type = trim($_POST["vote"]);

    //get unique content ID and sanitize it (cos we never know).
    $unique_content_id = filter_var(trim($_POST["unique_id"]),FILTER_SANITIZE_STRING, FILTER_FLAG_STRIP_LOW | FILTER_FLAG_STRIP_HIGH);

    //Convert content ID to MD5 hash (optional)
    $unique_content_id = hash('md5', $unique_content_id);

    //check if its an ajax request, exit if not
    if(!isset($_SERVER['HTTP_X_REQUESTED_WITH']) AND strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) != 'xmlhttprequest') {
        die();
    }


    switch ($user_vote_type)
    {          

        ##### User liked the content #########
        case 'up':

            //check if user has already voted, determined by unique content cookie
            if (isset($_COOKIE["voted_".$unique_content_id]))
            {
                header('HTTP/1.1 500 Already Voted'); //cookie found, user has already voted
                exit(); //exit script
            }

            //get vote_up value from db using unique_content_id
            $result = mysqli_query($sql_con,"SELECT vote_up FROM crewlist WHERE unique_content_id='$unique_content_id' LIMIT 1");
            $get_total_rows = mysqli_fetch_assoc($result);

            if($get_total_rows)
            {
                //found record, update vote_up the value
                mysqli_query($sql_con,"UPDATE crewlist SET vote_up=vote_up+1 WHERE unique_content_id='$unique_content_id'");
            }else{
                //no record found, insert new record in db
                mysqli_query($sql_con,"INSERT INTO crewlist (unique_content_id, vote_up) value('$unique_content_id',1)");
            }

            setcookie("voted_".$unique_content_id, 1, time()+7200); // set cookie that expires in 2 hour "time()+7200".
            echo ($get_total_rows["vote_up"]+1); //display total liked votes
            break; 

        ##### User disliked the content #########
        case 'down':

            //check if user has already voted, determined by unique content cookie
            if (isset($_COOKIE["voted_".$unique_content_id]))
            {
                header('HTTP/1.1 500 Already Voted this Content!'); //cookie found, user has already voted
                exit(); //exit script
            }

            //get vote_up value from db using unique_content_id
            $result = mysqli_query($sql_con,"SELECT vote_down FROM crewlist WHERE unique_content_id='$unique_content_id' LIMIT 1");
            $get_total_rows = mysqli_fetch_assoc($result);

           if (!mysqli_query($result, "SET a=1")) {
    printf("Errormessage: %s\n", mysqli_error($result));
}

            if($get_total_rows)
            {
                //found record, update vote_down the value
                mysqli_query($sql_con,"UPDATE crewlist SET vote_down=vote_down+1 WHERE unique_content_id='$unique_content_id'");
            }else{

                //no record found, insert new record in db
                mysqli_query($sql_con,"INSERT INTO crewlist (unique_content_id, vote_down) value('$unique_content_id',1)");
            }

            setcookie("voted_".$unique_content_id, 1, time()+7200);  // set cookie that expires in 2 hour "time()+7200".
            echo ($get_total_rows["vote_down"]+1);//display total disliked votes
            break; 

        ##### respond votes for each content #########     
        case 'fetch':
            //get vote_up and vote_down value from db using unique_content_id
            $result = mysqli_query($sql_con,"SELECT vote_up,vote_down FROM crewlist WHERE unique_content_id='$unique_content_id' LIMIT 1");
            $row = mysqli_fetch_assoc($result);

            //making sure value is not empty.
            $vote_up    = ($row["vote_up"])?$row["vote_up"]:0;
            $vote_down  = ($row["vote_down"])?$row["vote_down"]:0;

            //build array for php json
            $send_response = array('vote_up'=>$vote_up, 'vote_down'=>$vote_down);
            echo json_encode($send_response); //display json encoded values
            break;

    }

}

编辑：添加了表格行

编辑：请忽略一切，我在MySQL表中有语法错误！我没有使用vote_down投票和投票 - 投票 - 投票。我有固定的喜欢系统，但无论何时我点击“喜欢”，它都会向表中添加一个新行。谁知道为什么？

现在是我的错误！