PHP MySQL DELETE row from html table with link button - php

Question

I've been looking at this for some time now, all I'm doing is learning PHP with mysql, with no previous programming experience before these so please be kind. I need to delete an entire row from a table. The table is inside list.php and there's a delete button that redirects to delete.php. But all it does it redirects me to a blank page with an url something like "delete.php?id=4" depending on row ID, which seems to be correct.
This is connect.php:
<?php
$server = "localhost";
$db_user = "root";
$db_pass = "";
$db_name = "school";
$db_conn = mysqli_connect($server, $db_user, $db_pass, $db_name);
$connect_error = 'Sorry, we are experiencing connection problems';
mysql_connect('localhost', 'root', '') or die($connect_error);
mysql_select_db('school') or die($connect_error);
?>
And this is delete.php :
<?php
if(isset($_GET['ID'])){
$courseID = $_GET['ID'];
$sql_delete = "DELETE FROM Courses WHERE ID = $courseID";
print ($sql_delete);
$result = mysqli_query($db_conn,$sql_delete);
if($result) {
echo "Congratulations. You have deleted this course succesfully.";
header('location:list.php');
} else {
echo "Error";
error_reporting(E_ALL ^ E_DEPRECATED);
}
}
?>
Notice "print ($sql_delete);", which doesn't print anything either. All I can think of is there is something wrong with the way I am asking for the ID by using $_GET, but can't get my head around it. When I run
"DELETE FROM Courses WHERE ID = 4;"
inside xampp's mysql module, it works. Uhm... oh well.
OK, let me add:
This is actually my delete button inside list.php, which gives me an URL based on table row number, based on Course id.
<?php echo "<td>Delete";?>

Answer 1

connect.php
$server = "localhost";
$db_user = "root";
$db_pass = "";
$db_name = "school";
$db_conn = mysqli_connect($server, $db_user, $db_pass, $db_name);
delete.php
if(isset($_GET['ID'])){
$courseID = $_GET['ID'];
$sql_delete = "DELETE FROM Courses WHERE ID = $courseID";
$result = mysqli_query($db_conn,$sql_delete);
if(mysqli_affected_rows($db_conn)>0) {
header('location:list.php?result=success');
} else {
header('location:list.php?result=fail');
}
}
list.php (Where is delete button)
<?php
if(isset($_GET['result'))
{
if($_GET['result']=='success')
{
echo "Congratulations. You have deleted this course succesfully.";
}
else{
echo "error";
}
}
?>
(Delete button)
<a href="delete.php?ID=5" >Delete</a>