Every time I edit a row, it creates another row - php

Question

I'm creating a simple PHP and SQL to do list application. My problem is, every time I edit a row, it creates another row instead of just editing the existing row. Here is some of the code from index.php:
<?php
$current_date = date("Y-m-d");
if ($_SERVER['REQUEST_METHOD'] == 'POST'){
$task = isset($_POST['task']) ? $_POST['task'] : null;
$importance = isset($_POST['importance']) ? $_POST['importance'] : null;
$due_date = isset($_POST['due_date']) ? $_POST['due_date'] : null;
$order = isset($_POST['order']) ? $_POST['order'] : null;
if(isset($task,$importance,$due_date,$user_name)){
$sql = "INSERT INTO tasks (task, importance, due_date, user_name) VALUES ('$task', '$importance', '$due_date', '$user_name')";
$result = mysqli_query($connection, $sql) or die(mysqli_error($connection));
}
}
?>
<?php
while($column = mysqli_fetch_assoc($result)){
?>
<tr><td><?php echo $column["task"]?></td><td class="<?php echo $column["importance"] ?>"><?php echo $column["importance"]?></td><?php if($column["due_date"]<$current_date){echo '<td class="overdue">';}else{echo '<td class="not_overdue">';} ?><?php echo $column["due_date"]?></td><td><?php echo "Delete" ?></td></tr>
<?php
}
?>
Here is some of the code from edit.php:
<?php
if($_GET['id'] != ""){
$task_id = $_GET['id'];
$task_id = base64_decode($task_id);
$sql = "SELECT * FROM tasks WHERE task_id='$task_id'";
$result = mysqli_query($connection, $sql) or die(mysqli_error($connection));
}
?>
<?php
}
?>
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST'){
$task = isset($_POST['task']) ? $_POST['task'] : null;
$importance = isset($_POST['importance']) ? $_POST['importance'] : null;
$due_date = isset($_POST['due_date']) ? $_POST['due_date'] : null;
if(isset($task,$importance,$due_date)){
$sql = "UPDATE tasks SET task='$task', importance='$importance', due_date='$due_date' WHERE task_id='$task_id'";
$result = mysqli_query($connection, $sql) or die(mysqli_error($connection));
}
}
?>
Can someone tell me what I'm doing wrong?

Answer 1

On your edit.php file the Form tag should have an Action pointing to edit.php to update.

Answer 2

I fixed this issue by removing the form action on edit.php. Original:
<form method="post" action="index.php">
New:
<form method="post">
I then added a redirect to the bottom of this code block on edit.php:
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST'){
$task = isset($_POST['task']) ? $_POST['task'] : null;
$importance = isset($_POST['importance']) ? $_POST['importance'] : null;
$due_date = isset($_POST['due_date']) ? $_POST['due_date'] : null;
if(isset($task,$importance,$due_date)){
$sql = "UPDATE tasks SET task='$task', importance='$importance', due_date='$due_date' WHERE task_id='$task_id'";
$result = mysqli_query($connection, $sql) or die(mysqli_error($connection));
header('Location: index.php');
}
}
?>

Answer 3

I suppose that on passing the task_id to edit.php you have a form for editing values and in that form, the action part should be updated to edit.php.