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{
    $name = $_POST['group_name'];
    $user_id = $_SESSION['user_id'];

    $stmt = $conn->prepare('INSERT INTO `_group_`(`name`, `user_id`) VALUES (:name,:user_id)');
    $stmt->execute(array(':name'=>$name, ':user_id'=>$user_id));
    header('Location: add-group.php');
    exit();
}

{

    $name = $_POST['group-name'];
    $user_id = $_SESSION['user_id'];

    $stmt = $conn->prepare('INSERT INTO `_group_`(`name`, `user_id`) VALUES (:name,:user_id)');
    $stmt->execute(array(':name'=>$name, ':user_id'=>$user_id));

    header('Location: add-group.php');
    exit();
}