Editing a form in MySQL and PHP - php

Question

I am working on a project. What I need to do is basically enter some info into a form, have that form save it into a database, display the data, and then be able to edit the data. So far, I am able to do everything except edit the data. I've tried using $_GET to get the ID of the particular "bug" I need to edit, and I am able to do that, and get all of the information but I am not sure how to edit that particular ID in my database. Here is my handler: http://pastebin.com/mR6QWpJ7 and my form:
<form action="week10handle.php" method="POST">
<fieldset width="300px">
<legend width="300px"><b>Add a bug report</b></legend>
Product Name:<br/><input type="text" name="product_name"><br/>
Product Version: <br/><input type="text" name="product_version"><br/>
Hardware Type: <br/><input type="text" name="hardware"><br/>
Operating System: <br/><input type="text" name="os"><br/>
Frequency: <br/><input type="text" name="frequency"><br/>
Proposed Solutions: <br/><textarea name="solutions"></textarea><br/>
<input type="submit" value="Submit">
</fieldset>
</form>
Here is where I obtain the get data in my edit form page so far, but as of right now, I am not sure how to edit a particular ID in the database.
$getbug = htmlspecialchars($_GET["bugid"]);
if (!empty($getbug)){
$getbuginfo = mysql_query("SELECT * FROM `bugs` WHERE `id`= '$getbug'");
if ($getbuginfo = mysql_fetch_assoc($getbuginfo)){
$edit_product_name = $getbuginfo['product_name'];
$edit_prod_version = $getbuginfo['product_version'];
$edit_hardware = $getbuginfo['hardware_type'];
$edit_os = $getbuginfo['os'];
$edit_frequency = $getbuginfo['frequency'];
$edit_solutions = $getbuginfo['solutions'];
?>
<form action="week10handle.php" method="POST">
<fieldset width="300px">
<legend width="300px"><b>Edit bug <?php echo $getbug;?></b></legend>
Product Name:<br/><input type="edit" name="product_name" value="<?php echo $edit_product_name;?>"><br/>
Product Version: <br/><input type="edit" name="product_version" value="<?php echo $edit_prod_version;?>"><br/>
Hardware Type: <br/><input type="edit" name="hardware" value="<?php echo $edit_hardware;?>"><br/>
Operating System: <br/><input type="edit" name="os"value="<?php echo $edit_os;?>"><br/>
Frequency: <br/><input type="edit" name="frequency"value="<?php echo $edit_frequency;?>"><br/>
Proposed Solutions: <br/><textarea name="solutions"><?php echo $edit_product_name;?></textarea><br/>
<input type="submit" value="Submit">
</fieldset>
</form>
EDIT: Here is my update php code, but it is still not working, when I submit my form, it refreshes the page, but it doesn't update the database:
<?php
if (mysql_connect('localhost','root','') && mysql_select_db('bug_reports')){
$errors = array();
if (isset($_POST['product_name'], $_POST['product_version'],$_POST['hardware'],$_POST['os'],$_POST['frequency'], $_POST['solutions'])){
$product_name = mysql_real_escape_string(htmlentities($_POST['product_name']));
$product_version = mysql_real_escape_string(htmlentities($_POST['product_version']));
$hardware = mysql_real_escape_string(htmlentities($_POST['hardware']));
$os = mysql_real_escape_string(htmlentities($_POST['os']));
$frequency = mysql_real_escape_string(htmlentities($_POST['frequency']));
$solutions = mysql_real_escape_string(htmlentities($_POST['solutions']));
$getbug = mysql_real_escape_string(htmlentities($_POST['bugid']));
if (empty($product_name) || empty($product_version) || empty($hardware) || empty($os) || empty($frequency) || empty($solutions)){
$errors[] = 'All fields are required.';
}
if (!is_numeric($product_version) || !is_numeric($frequency)){
$errors[] = 'Product version and frequency must both be numbers';
}
if (empty($errors)){
$update = "UPDATE `bugs` SET `product_name` = '$product_name', `product_version = '$product_version', `hardware_type = '$hardware', `os` = '$os', `frequency` = '$frequency', `solutions` = '$solutions' WHERE `id` = $getbug";
if ($update = mysql_query($update)){
header('Location: week10handle.php');
} else{
$errors[] = 'Something went wrong, please try again.';
}
} else{
foreach($errors as $error){
echo '<p><strong>'.$error.'</strong></p>';
}
}
}else{
$getbug = htmlspecialchars($_GET["bugid"]);
}
if (!empty($getbug)){
$getbuginfo = mysql_query("SELECT * FROM `bugs` WHERE `id`= '$getbug'");
if ($getbuginfo = mysql_fetch_assoc($getbuginfo)){
$bugid = $getbuginfo['id'];
$edit_product_name = $getbuginfo['product_name'];
$edit_prod_version = $getbuginfo['product_version'];
$edit_hardware = $getbuginfo['hardware_type'];
$edit_os = $getbuginfo['os'];
$edit_frequency = $getbuginfo['frequency'];
$edit_solutions = $getbuginfo['solutions'];
?>
<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="POST">
<fieldset width="300px">
<legend width="300px"><b>Edit bug <?php echo $getbug;?></b></legend>
Product Name:<br/><input type="edit" name="product_name" value="<?php echo $edit_product_name;?>"><br/>
Product Version: <br/><input type="edit" name="product_version" value="<?php echo $edit_prod_version;?>"><br/>
Hardware Type: <br/><input type="edit" name="hardware" value="<?php echo $edit_hardware;?>"><br/>
Operating System: <br/><input type="edit" name="os"value="<?php echo $edit_os;?>"><br/>
Frequency: <br/><input type="edit" name="frequency"value="<?php echo $edit_frequency;?>"><br/>
Proposed Solutions: <br/><textarea name="solutions"><?php echo $edit_product_name;?></textarea><br/>
<input type="hidden" name="bugid" value="<?php echo $bugid;?>" >
<input type="submit" value="Update">
</fieldset>
</form>
<?
}else{
echo "something went wrong";
}
}else{
echo "No bug found.";
}
}else
echo 'Could not connect at this time.';
?>

Answer 1

A typical way to detect an update, as opposed to an insert, would be to check for a value for id. So, in your edit form add a hidden field to pass the id to the handler and then in your handler you can decide whether to process it as insert or update based on the presence of the id field.
if (isset($_GET['id']) {
// do update
$sql = 'UPDATE `bugs` SET ... WHERE id = ' . intval($_GET['id']);
} else {
// do insert
$sql = 'INSERT INTO `bugs` VALUES ....';
}

Answer 2

UPDATE `bugs` SET `product_name` = '...', `product_version` = '...', ... WHERE `id` = $bugid;
Where the "..." will be replaced with newly $_POST-ed values for each column