¿How to show related products to the shopping cart products?

Question

I want to show indifferent result that the user have added in the shopping cart.

I get the ID from the product by method GET, by click a url.

<a href=http:./cart/$id/$url>

My example

The products table have only 6 records, that is to say 6 products to buy.

Now, if the user add 3 products to buy, with id5 ​​id1 id3

now my question is, how can i show others products from table products, that have not been purchased by user, in this case id2 id4 id6, as I mentioned before id5 ​​id1 id3 is purchased.

The query that i will generated for the indifferent results of the shopping cart is like this:

 $result = $c->prepare("SELECT id_tutorial,page,titulo,info,icon,bg,vdo,url,precio,duracion,status FROM tutoriales WHERE id_tutorial!=? and status=1 LIMIT 6");

I´m spending a logic != or <>

But I don´t know the process must take before working with this query result.

Here is my Shopping cart code card.php:

<?php //Shopping Cart (./cart.php)

//GET -> id of the product.
if (isset($_GET['articulo'])) {

    $id_tutorial = $_GET['articulo'] ?: '';

    //If the session is defined for Shop Cart.
    if (isset($_SESSION['carrito'])) {

        //Get data from session.
        $arreglo = $_SESSION['carrito'];
        $encontro = false;      

        for ($i=0; $i<count($arreglo); $i++) { 
            //checking if product has already been added to the cart.
            if ($arreglo[$i]['Id'] == $_GET['articulo']) {
                $encontro = true;               
            }
        }
        //If find product is false, update de array session (Shop cart).
        if ($encontro == false) {           
            //Reset
            $titulo = "";
            $precio = 0;            
            $icon = "";
            //Get data from DB.
            $stmt = $c->prepare("SELECT titulo,precio,icon FROM tutoriales WHERE page=? and status=1");
            $stmt->bind_param("i",$_GET['articulo']);
            $stmt->execute();
            $stmt->store_result();
            if ($stmt->num_rows > 0) {
                $stmt->bind_result($titulo,$precio,$icon);
                while ($stmt->fetch()) {

                    //New data for array.           
                    $datosnuevos = ['Id' => $_GET['articulo'], 'Titulo' => $titulo, 'Precio' => $precio, 'Icon' => $icon, 'Cantidad' => 1 ];

                    //array_push($arreglo, $datosnuevos); 
                    $arreglo[] = $datosnuevos;
                    $_SESSION['carrito'] = $arreglo;

                    //Count total of products added to the cart.
                    $data = $_SESSION['carrito'];
                    $value_carrito = count($data);
                    $_SESSION['compras'] = $value_carrito;

                } $stmt->close();


            } else {
                $stmt->close();
            }
        }   

    } else { //If session is not defined for Shop Cart, that is to say that the card is in 0 productos.

        //Reset.
        $titulo = "";
        $precio = 0;
        $icon = "";
        //Get data from DB.
        $stmt = $c->prepare("SELECT titulo,precio,icon FROM tutoriales WHERE page=? and status=1");
        $stmt->bind_param("i",$_GET['articulo']);
        $stmt->execute();
        $stmt->store_result();
        if ($stmt->num_rows > 0) {
            $stmt->bind_result($titulo,$precio,$icon);
            while ($stmt->fetch()) {

                //Started the array for Shop Cart.
                $arreglo[] = ['Id' => $_GET['articulo'], 'Titulo' => $titulo, 'Precio' => $precio, 'Icon' => $icon, 'Cantidad' => 1 ];
                $_SESSION['carrito'] = $arreglo;

                //Count total of products added to the cart.
                $data = $_SESSION['carrito'];
                $value_carrito = count($data);
                $_SESSION['compras'] = $value_carrito;

            } $stmt->close();

        } else {
            $stmt->close();
        }           
    }

}
?>

Answer 1

This fiddle will give you a head start on how to construct your SELECT query,

• http://sqlfiddle.com/#!9/e26d17/1

Suppose $_SESSION['carrito'] contains the products which have already been purchased by the customer and $_SESSION['compras'] keeps the count of total number of products purchased, the SELECT query to fetch the remaining products would be like this:

SELECT id_tutorial,page,titulo,info,icon,bg,vdo,url,precio,duracion,status,id_nivel,id_estado 
FROM tutoriales 
WHERE status = 1 AND id_tutorial NOT IN (
    SELECT id_tutorial 
    FROM tutoriales 
    WHERE id_tutorial IN (" . rtrim(str_repeat("?,", $_SESSION['compras']), ",") . "
    )
)

And your code should be like this:

// your code

$stmt = $c->prepare("SELECT id_tutorial,page,titulo,info,icon,bg,vdo,url,precio,duracion,status,id_nivel,id_estado FROM tutoriales WHERE status = 1 AND id_tutorial NOT IN (SELECT id_tutorial FROM tutoriales WHERE id_tutorial IN (" . rtrim(str_repeat("?,", $_SESSION['compras']), ",") . "))");
$param = array(); 
$paramType = '';
for($i = 0; $i < $_SESSION['compras']; ++$i){
    switch(gettype($_SESSION['carrito'][$i]['Id'])){
        case 'boolean':
        case 'NULL':
        case 'integer':
            $paramType .= 'i';
            break;
        case 'double':
            $paramType .= 'd';
            break;
        case 'string':
            $paramType .= 's';
            break;
        default:
            $paramType .= 'b';
    }
    $param[] = &$_SESSION['carrito'][$i]['Id'];
}
array_unshift($param, $paramType);
call_user_func_array(array($stmt, 'bind_param'), $param);

$stmt->execute();
$stmt->store_result();
if ($stmt->num_rows > 0) {
    $result->bind_result($id_tutorial,$page,$titulo,$info,$icon,$bg,$vdo,$url,$precio,$duracion,$status,$id_nivel,$id_estado);
    while ($result->fetch()){

        // your code          

    }
} else {
    $stmt->close();
}