All Questions

To show related product, I chose the value by GET method, in this case the value is the id of the product.

It obtained the data through a query, in this case the example is the colors that the product has.

$sql = "SELECT * FROM colors WHERE product_id='$id'";

Now in the shopping cart I want to show a section that indicates you might also be interested in these products.

Suppose in the database named products you have 6 products.

    id | producto
------ | ------
     1 | Cell
     2 | Cell
     3 | Cell
     4 | Cell
     5 | Cell
     6 | Cell

And in the shopping cart I add the products with the id 1,3,6

As I show in the section you could also be interested in these products except the products already added to the basket.

I have only tested with a product like the example already mentioned.

In this case, how would it be considered or how would the query be.

To show only the products not added to the shopping cart.

This is my shopping cart card.php

 //Carro de la compra

//Si esta definida la ID obtenido por URL
if (isset($_GET['articulo'])) {

    $id_tutorial = $_GET['articulo'];//Obtenemos el ID del producto añadido, para poder acer comprobaciones a mostrar otros resultados.

    //Si esta definido la sesion carro -> es decir si ay algun articulo comprado
    if (isset($_SESSION['carrito'])) {

        $arreglo = $_SESSION['carrito'];
        $encontro = false;      

        for ($i=0; $i<count($arreglo); $i++) { 

            if ($arreglo[$i]['Id'] == $_GET['articulo']) {
                $encontro = true;               
            }
        }

        if ($encontro == false) {


            $titulo = "";
            $precio = 0;
            $precioUSD = 0;
            $icon = "";

            $stmt = $c->prepare("SELECT titulo,precio,icon,id_autor FROM products 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,$id_autor);
                while ($stmt->fetch()) {

                    //Sentencia prepare -> autor proyecto
                    $stmtN = $c->prepare("SELECT autor FROM autor WHERE id_autor=?");           
                    $stmtN->bind_param("i", $id_autor);         
                    $stmtN->execute();          
                    $stmtN->bind_result($autor);            
                    $stmtN->fetch();            
                    $stmtN->close();

                    $datosnuevos = array('Id' => $_GET['articulo'], 'Titulo' => $titulo, 'Precio' => $precio, 'Icon' => $icon, 'Cantidad' => 1 );

                    /*
                        #Si se utiliza array_push() para añadir un solo elemento al array, es mejor utilizar $array[] = ya que de esta forma no existe la sobrecarga de llamar a una función. 
                    */

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

                    $data = $_SESSION['carrito'];
                    $value_carrito = count($data);
                    $_SESSION['compras'] = $value_carrito;

                } $stmt->close();


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

    } else { //Caso falso añadimos primer articulo al carro

        $titulo = "";
        $precio = 0;
        $precioUSD = 0;
        $icon = "";

        $stmt = $c->prepare("SELECT titulo,precio,icon,id_autor FROM products 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,$id_autor);
            while ($stmt->fetch()) {

                //Sentencia prepare -> autor proyecto
                $stmtN = $c->prepare("SELECT autor FROM autor WHERE id_autor=?");           
                $stmtN->bind_param("i", $id_autor);         
                $stmtN->execute();          
                $stmtN->bind_result($autor);            
                $stmtN->fetch();            
                $stmtN->close();

            } $stmt->close();

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

            $arreglo[] = array('Id' => $_GET['articulo'], 'Titulo' => $titulo, 'Precio' => $precio, 'Icon' => $icon, 'Cantidad' => 1 );

            $_SESSION['carrito'] = $arreglo;

            $data = $_SESSION['carrito'];
            $value_carrito = count($data);
            $_SESSION['compras'] = $value_carrito;

            //echo "<script>window.location.reload();</script>";


    }

}

Update additional details.

The product table.

 id_product       Producto          Marca    subcategoría
-------------  ----------------  ----------    ------
      1          Mini Parlantes       0           1
      2          flash Memory         0           1

The category table.

 id    cat_name   categoría
----  ---------- -----------
 1       HP          0             
 2   accesorios      1             
 3    Samsung        0                       

Structure:

<!-- language: lang-none -->

CREATE TABLE IF NOT EXISTS categories (
 id int(100) NOT NULL,
 cat_name text NOT NULL,
 categoria int(5) NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1;

1. hp
   • Accessories
2. Samsung
   • Accessories

In the HP category we show all HP brand products including accessories among others.

In the accessories subcategory we only show these products: flash memory, speakers, headphones, etc.

Note: Accessories are shown to the corresponding brand.

Now it is a product that does not belong to accessories, for example, a laptop subcategory instead of value 1 is NULL, this product would only be shown in the main category HP.

In the event that there was another subcategory called lapto, this product would be shown in that subcategory.

I have this code:

Scanner scan = new Scanner(System.in);
    
String s2 = scan.nextLine();
int i2    = scan.nextInt();
    
System.out.println("natural= " + i2);
System.out.println("cadena = " + s2);
    
scan.close();

Which works correctly:

This is a string
1714
natural= 1714
string = This is a string

But if I change the order of the lines of the Scanner:

int i2    = scan.nextInt();
String s2 = scan.nextLine();

It ignores the line scan.nextLine()and gives me the result right after I enter the int.

1714
natural= 1714
chain =

Does anyone know what is going on and how to fix it?

Traditionally, the recommendation for variable and method names in programming languages ​​has always been not to use special characters, including Ñ.

Following tradition I still call the variables "year" "annio", even other programmers use "ano","anno","anho","year", etc.; even though currently Visual Studio allows calling the "Year" variable without any problems when compiling.

I was wondering what prevents me from using the word "year" and would like to know if there are any standards or defined good/bad practices for using such "special" characters in a variable name: the good, the bad, and the ugly; any reference or comment about it will be useful to me.

I have a table like this, which has two rows:

nombre_per   | apellido_per   | permisos_busqueda_per
-------------+----------------+----------------------
Mattew       | Janeey         | SI
Janny        | Pineda         | NO

My question is the following

SELECT nombre_per, apellido_per, permisos_busqueda_per 
FROM   la_tabla 
WHERE  nombre_per LIKE '%a%' OR apellido_per LIKE '%a%' AND permisos_busqueda_per="SI"

If I'm looking only for users who have the findable permission enabled permisos_busqueda_per, why does it return both rows if Janny doesn't have the findable permission enabled?

I have a class to save the email and user that connect in the application with sharedpreferences, but it saves the data without any keyreference, so when I want to save a different data without overwriting the previous one, it does not do it, I imagine that I will need to assign some keyto reference it and be able to save the data I want without stepping on the previous one and assigning it a name:

public void save(Context context, String text) {
    SharedPreferences settings;
    Editor editor;

    settings = PreferenceManager.getDefaultSharedPreferences(context);

    editor = settings.edit();

    editor.putString(PREFS_KEY, text);

    editor.commit();
}

Here I call the function:

String email = _emailText.getText().toString();
sharedPreference.save(this, email);