后台工作更新脚本不工作

Question

I created an background working script, that updates my database table on a condition.

Here is my main script:

<?php
require_once('conn.php');

$query = "SELECT * FROM user WHERE id = '" . $_COOKIE['username'] . "'";
$data = mysqli_query($dbc, $query);
$row = mysqli_fetch_array($data);

if($row['ehp'] > $row['required_ehp']) {
    // The 'ehp' column is greater than 'required_php'
    $calc = $row['ehp'] % $row['required_ehp'];
    $new = $row['required_ehp'] * 12;
    $new_lvl = $row['level'] + 1;

    $query2 = "UPDATE user set level = '$new_lvl', ehp = '$calc', required_ehp = '$new'";
    mysqli_query($dbc, $query2);
    echo 'query successful';

} else {
    echo 'query unsuccessful' . mysql_error();   
}
 echo $row['ehp'] % $row['required_ehp'];
echo   $row['required_ehp'];

?>

The error message I am getting from this script is:

query unsuccessful
Warning: Division by zero in H:\AppServ\www\sp\userlevel.php on line 21

I don't know what's is wrong. Please help me.

Here is the database column's image.

Answer 1

Okay I found out my mistake it was just that in id in my database, I was searching for the username column. Sorry to bother you all.