Catchable fatal error: Object of class PDOStatement could not be converted to string in line 114

Question

I\'m trying to add some data to my database, but I\'m getting the error Catchable fatal error: Object of class PDOStatement could not be converted to string in /var/www/mand

Answer 1

foreach($_SESSION["cart"] as $id => $value)
{

        $query = $db->query('SELECT * FROM Producten WHERE ProductID ="'.$id.'" ');
        $query->execute();

        while($row = $query->fetch(PDO::FETCH_ASSOC))
        {

            $price = $row['Prijs'];
            $ProductID = $row['ProductID'];

        }

$array = array( $max, $ProductID, $value, $price );

$sql->prepare
    ("
    INSERT INTO Bestellingsdetail (Bestelnummer, ProductID, Aantal, Prijs)
    VALUES (?, ?, ?, ?)
    ")

$sql->execute($array);

}