PDO DELETE query Invalid parameter number: parameter was not defined

Question

I am having issues getting a PDO prepared DELETE query to work. I am unsure of how I need to structure the bindParam in this instance. I get this warning:

Warning: PDOStatement::execute(): SQLSTATE[HY093]: Invalid parameter number: parameter was not defined

What am I doing wrong?

if(isset($_POST['delete'])) {
    $id = $_POST['id'];
    $stmt = $dbc->prepare("DELETE FROM users WHERE id = ?");
    $stmt->bindParam(' :id', $id);
    $stmt->execute();
}

<form method="POST">
            <tr>
                <td><input name="id" value="<?php echo $row['id'];?>" readonly></td>
                <td><input name="first" value="<?php echo $row['first'];?>"></td>
                <td><input name="last" value="<?php echo $row['last'];?>"></td>
                <td><input name="product" value="<?php echo $row['product'];?>"></td>
                <td><button name="save" type="submit">Save</button></td>
                <td><button name="delete" type="submit">Delete</button></td>
            </tr>
        </form>

This? `$stmt = $dbc->prepare("DELETE FROM users WHERE id = :id");` This didn't work. — Paul, Apr 07 '16 at 02:32
Did you update the binding as well? `$stmt->bindParam(':id', $id);` — chris85, Apr 07 '16 at 02:51
Wow, I thought he was only referring to the one with the question mark. That did it. Thanks — Paul, Apr 07 '16 at 02:52

David ROUMANET · Answer 1 · 2022-03-19T14:41:45.067

-1

In fact, with PDO, you've to give the type, else it's replaced by a string (your ID is probably an int). Use the optional parameter PDO::PARAM_INT So the code should be :

if(isset($_POST['delete'])) {
    $id = $_POST['id'];
    $stmt = $dbc->prepare("DELETE FROM users WHERE id = :id");
    $stmt->bindParam(' :id', $id, PDO::PARAM_INT);
    $stmt->execute();
}

You could find other types on official documentation : https://www.php.net/manual/en/pdo.constants.php

And if you're interested why the type FLOAT isn't here, follow the white rabbit on Stackoverflow : PDO::PARAM_FLOAT does not exist, why?

Hope to help you with my answer, like I've just discovered few minuts ago.

edited Mar 19 '22 at 14:41

answered Mar 19 '22 at 14:12

David ROUMANET

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this information is correct by itself but absolutely unhelpful beceause unrelated to the question asked – Your Common Sense Mar 19 '22 at 17:44
Thanks but I feel my answer will help anyway... The closed part with a link to another answer is far more complicated for an non english. I assume stackoverflow is running like wikipedia with big gurus able to make sun and rain: no problem with that :-\ – David ROUMANET Mar 22 '22 at 06:56

PDO DELETE query Invalid parameter number: parameter was not defined

1 Answers1