注意：未定义的索引：comment_author

Question

I tried many things from StackOverflow regarding this error but with no luck.

I try to show a reply from a comment. The reply comment is shown along with the date and hour when posted but the author who posted the reply is not shown.

The page with error is comments.php on the line $com_name = $row['comment_author'];

The code is:

<?php
    $get_id = $_GET['post_id'];

    $get_com = "select * from comments where post_id='$get_id'";

    $run_com = mysqli_query($con, $get_com);

    while($row=mysqli_fetch_array($run_com)){

        $com = $row['comment'];
        $com_name = $row['comment_author'];
        $date = $row['date'];

        echo "

            <div id='comment'>
            <h3>$com_name</h3><i>Said</i> on $date
            <p>$com</p>
            </div>
        ";
    }
?>

Hope to sort out this error.

Thank you and best regards.

Answer 1

It looks like there are no column with name comment_author. But there are field user_id. You need to modify you query to below (assume user table users has fields user_name and user_id)

$get_com = "select c.date, c.comment, u.user_name as comment_author 
    from comments c inner join users u on c.user_id = u.user_id 
    where c.post_id='$get_id'";