Deleting Records with PHP/MySQL

[RobAC]

I am in the process of designing a web based gui page that gives somone the option so editing or deleting a record in a database. Ideally, I would like to have the Edit/Delete links side by side. The edit links bring the user to a special form that is populated with the data from that record and they can edit the data from there. However, I would like to have the delete link simply delete that record when clicked on and return the user back to the edit/delete form. Is this possible and what would be the syntax to do so?

I've searched the PHP/MySQL books, but haven't found exactly what I'm looking for.

[Chris82]

Hi.

you need to somehow pass an identification for the record either via a GET variable or a hidden form field. A GET variable is probably the easiest way, but it can be misused as easily.

This is an example using a GET variable.

// display.php -- displaying the records
while ($data = mysql_fetch_row($query)) {
    // in this example $data[0] holds the record id
    // display the record here
    // add an delete link using:
    echo '<a href="delete.php?id=' . $data[0] . '">delete record</a>';
} 

And on page delete.php you can access the parameter which was passed via the QUERY_STRING. You probably need to add some safety checks to make sure that only the selected records are deleted.

// delete.php -- deleting records
$id = (int)$_GET['id'];
mysql_query("DELETE FROM yourtable WHERE id = $id");
// redirect the user to another url
header('Location: http://www.domain.com/page.php');
exit(); 

Christian

[weirdbeardmt]

This is fairly simple and there are a multitude of ways to do it. The simplest is probably:

if your page was called page.php then next to your item to be deleted you would have a delete link which went to page.php?action=delete&id=whatever [this is some link - how you reference your rows in the db)

Once clicked it reloads the page. You need to check if action was set to delete:

if(isset($_GET["action"]) && $_GET["action"]=="delete") { 

Then just run your delete syntax. It'd be worth checking that the id you use is valid (i.e stop malicious users having a go at your DELETE command... for example, make sure the id is an int with is_int for example up to you really).

[RobAC]

This looks like what I'm looking for. I'll give this a try. Thanks Christian!

[PHP John]

Yes, it is possible.

You could do it several ways. The first way would be to populate the link like this:

<a href="[add/delete form script]?action=delete&record=[record number]

</DIV><DIV> </DIV><DIV>Another way to do it would be to have a "submit" button that has a value of "Delete":

<form action="[add/delete form script]" method="post">
<input type="hidden" name="record" value="[record number]" />
<input type="submit" name="submit" value="Delete" />
</form>

Then at the top of your add/delete form script you would test for a value of $_POST['submit']. If this has the value of "Delete" you would retrieve the record number this way:

$record = $_POST['record'];
// Then you would execute your query here
mysql_query( "DELETE FROM [table name] WHERE userId = '$userId' AND recordId = $record"); 

This is, of course, quite sketchy, but hopefully it will give you a bump in the right direction.

[Jeff Lange]

You may also want to add a confimation javascript popup and/or a confirmation page.

(depending on what sort of data it is of course)