数据未显示在Wamp服务器数据库上（使用php）

Question

I'm trying to INSERT data into a table in my database but I'm not able to. I'm using WAMP.

PHP Script:

$user = 'root';
$password = '';
$db = 'comments_schema';
$host = 'localhost:3306';

$mysqli = mysqli_connect('localhost', $user, $password, $db);

$sql = "INSERT INTO parent_comment(commentid, comment) VALUES ('". '   
commentid'."', '". "hi" ."')";
$result = $mysqli->query($sql);

if($result > 0):
    echo 'Successfully posted';
else:
    echo 'Unable to post';
endif;

HTML Code:

</div>
    <form action="database.php" method="post">
        Comments: <input type="text" name="field_name" />
        <input type="Submit" /></form>

However, the rows could not be inserted:

Answer 1

You can try this code:

'INSERT INTO parent_comment(commentid, comment) VALUES ('.commentid.', "hi")';