Question

When I ran this piece of code

<?php

include '../bin/config.php';
connect();

if (isset($_GET['id']) && is_numeric($_GET['id'])){

    $id = $_GET['id'];
    $stmt = $conn->prepare("DELETE FROM noteline WHERE Nid = ?");
    $stmt->bindParam(1, $id, PDO::PARAM_INT);

    $outcome = $stmt->execute();

    if ($outcome){

        echo 'it was successfully deleted';
        header("Location: ../noteline");
    }else {

        echo 'it was not successful due to something';
    }
}


?>

it echoed “it was successfully deleted” but nothing was deleted from my database…
but when I started a transaction by modified this code like this:

<?php

include '../bin/config.php';
connect();

if (isset($_GET['id']) && is_numeric($_GET['id'])){

    $id = $_GET['id'];
    $stmt = $conn->prepare("DELETE FROM noteline WHERE Nid = ?");
    $stmt->bindParam(1, $id, PDO::PARAM_INT);

    $conn->beginTransaction();
    $outcome = $stmt->execute();

    if ($outcome){

        $conn->commit();
        echo 'it was successfully deleted';
        header("Location: ../noteline");
    }else {

        echo 'it was not successful due to something';
    }
}


?>

My data was finally deleted from my MySQL database!
I want to know why?

Answer 1

Because the PDO connection is operating with auto-commit mode disabled. Look into the connect() function to ensure that you don’t disable this mode.

(Also, I see you’re using a global variable to store the connection object. Avoid global variables where possible.)