Delete from database depending on button clicked

Question

I have a script that prints in the screen all the data of a table. Associated to each row of data, I have a delete button, and I would like that, when a button of any row is cliked, the row is deleted. To do so, I have got the following code:

$con = mysqli_connect("","","","");

$result = mysqli_query($con,"SELECT * FROM `clientes_pmt`");

while($row = mysqli_fetch_array($result)){
    ?> <button name="delete" value="<?php echo $row['id']; ?>" type="submit"><img src="paginas/borrar.jpg" /></button>
    <a href="page<?php echo $row['nombre']; ?>">
        <div><p><?php echo $row['nombre']; ?></p></div>
        <div><p><?php echo $row['pais']; ?></p></div>
    </a>
    <section class="clearboth"></section><br><?php
}

if(isset($_POST['delete'])){
    $id = $_POST['delete'];
    $result = mysqli_query($con,"DELETE FROM `clientes_pmt` WHERE id = '$id'");
}

mysqli_close($con);

I receive no errors but the row is not being deleted.

Just seen it. Thank you, I knew it was something really stupid — alberzyzz, Jul 10 '17 at 08:08
To prevent SQL injections it would be wise to read up on PDO prepared statements. [More on preventing SQL injections](https://stackoverflow.com/questions/60174/how-can-i-prevent-sql-injection-in-php). [Are they sufficient to prevent SQL injection?](https://stackoverflow.com/questions/134099/are-pdo-prepared-statements-sufficient-to-prevent-sql-injection) — JiFus, Jul 10 '17 at 08:10
also in delete query it should be `id = $id`, as it will not be string — Jigar Shah, Jul 10 '17 at 08:10
make sure to check whether the POSTed "id" indeed belongs to current logged-in user before deleting the record — Prashant, Jul 10 '17 at 08:12

score 3 · Accepted Answer · answered Jul 10 '17 at 08:08

3

Enclose the button inside a form element and set appropriate action and method attributes, something like:

<form action="/delete.php" method="POST">
  <button ...> [your button]
</form>

answered Jul 10 '17 at 08:08

Prashant

5,331
10
44
59

score 0 · Answer 2 · answered Jul 10 '17 at 08:08

0

You have to modify these line

$con = mysqli_connect("localhost","root","","YOUR DATABASE NAME");

answered Jul 10 '17 at 08:08

Kap

11
2

score 0 · Answer 3 · answered Jul 10 '17 at 08:09

To see the result you can put a header() to the end of this part of code:

if(isset($_POST['delete'])){
    $id = $_POST['delete'];
    $result = mysqli_query($con,"DELETE FROM `clientes_pmt` WHERE id = '$id'");

    header('location:your_page_where_the_rows_are.php');
}

score 0 · Answer 4 · answered Jul 10 '17 at 08:17

0

I think it may be because the $id was not getting added into the query. Try bellow?

if(isset($_POST['delete'])){ $id = $_POST['delete']; $result = mysqli_query($con,"DELETE FROM clientes_pmt WHERE id = '".$id."'); }

answered Jul 10 '17 at 08:17

GrimeO

1

score 0 · Answer 5 · answered Jul 10 '17 at 08:19

Use Form tag and Header for redirect your page on same page. Try This -

<?php
$con = mysqli_connect("","","","");

$result = mysqli_query($con,"SELECT * FROM `clientes_pmt`");

while($row = mysqli_fetch_array($result)){
    ?> 
    <form action="" method="post" >
    <button name="delete" value="<?php echo $row['id']; ?>" type="submit"><img src="paginas/borrar.jpg" /></button>
    </form>
    <a href="page<?php echo $row['nombre']; ?>">
        <div><p><?php echo $row['nombre']; ?></p></div>
        <div><p><?php echo $row['pais']; ?></p></div>
    </a>
    <section class="clearboth"></section><br><?php
}

if(isset($_POST['delete'])){
    $id = $_POST['delete'];
    $result = mysqli_query($con,"DELETE FROM `clientes_pmt` WHERE id = '$id'");
    header('location:'.$_SERVER['PHP_SELF']);
}

mysqli_close($con);
?>

Delete from database depending on button clicked

5 Answers5