<?php
session_start();
include("config.php");
$dbh = new PDO($dbstr);
$id=$_POST["id"];
$pid=$_POST["pid"];

$stm=$dbh->prepare("SELECT rid FROM mono_achat WHERE rid= ?");
$stm->execute(array($id));
if ($stm->fetch()) {
    $stm2=$dbh->prepare("UPDATE mono_achat SET pid=? WHERE rid=?");
} else {
    $stm2=$dbh->prepare("INSERT INTO mono_achat(pid,rid) VALUES(?,?)");
}
$stm2->execute(array($pid,$id));
header("Location: disprue.php");