BD – Página 16 – Trifulcas

Hay que hacer varios pasos

 $server = "localhost";
$user = "root";
$password = "";
$db = "sakila";
try {
    $conn = new PDO("mysql:host=$server;dbname=$db;charset=UTF8", $user, $password);
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    //Los datos que tengo que insertar
    $pais = 'ArgentinaJarll';
    $ciudad = "La plata";
    $direccion = "Agla 6";
    $nombre = "Juan";
    $apellidos = "Pi";
    
    //Compruebo si existe el país consultando a la base de datos si hay
    //algún país que se llame como el que me han pasado
    $sql = "select * from country where country=:country";
    $parametros = [
        'country' => $pais
    ];
    $st = $conn->prepare($sql);
    $st->execute($parametros);
    $country = $st->fetch();
    
    //Si no existe lo inserto
    if (empty($country)) {
        $sql = "insert into country(country) values(:country)";
        $st = $conn->prepare($sql);
        $st->execute($parametros);
        $country_id = $conn->lastInsertId();
    } else {
        $country_id = $country['country_id'];
    }
      //Aquí ya tengo el país
    echo $country_id . "<br/>";

  
    //Hago la misma comprobación para la ciudad pero ojo, de ese país
    $sql = "select * from city where city=:city and country_id=:country_id";
    $parametros = [
        'city' => $ciudad,
        'country_id' => $country_id
    ];
    $st = $conn->prepare($sql);
    $st->execute($parametros);
    $city = $st->fetch();
    
    //Si no existe la ciudad la inserto
    if (empty($city)) {
        $sql = "insert into city(city,country_id) values(:city,:country_id)";
        $st = $conn->prepare($sql);
        $st->execute($parametros);
        $city_id = $conn->lastInsertId();
    } else {
        $city_id = $city['city_id'];
    }
    //Aquí ya tengo el id de la ciudad
    echo $city_id . "<br>";

    //A partir de aquí no compruebo más. Inserto la dirección con esa ciudad
    $sql = "insert into address (city_id,address) values (:city_id,:address)";
    $parametros = [
        'city_id' => $city_id,
        'address' => $direccion
    ];
    $st = $conn->prepare($sql);
    $st->execute($parametros);
    //Recupero el id de de esa dirección
    $address_id = $conn->lastInsertId();
    
    //Inserto el cliente con el id de la dirección y en store_id pongo un 1 directamente
    $sql = "insert into customer (address_id,first_name,last_name,store_id)"
            . " values (:address_id,:first_name,:last_name,1)";
    $parametros = [
        'address_id' => $address_id,
        'first_name' => $nombre,
        'last_name' => $apellidos
    ];
    $st = $conn->prepare($sql);
    $st->execute($parametros);
    echo "insertado el cliente con id ".$conn->lastInsertId();
} catch (Exception $e) {
    echo "Connection failed: " . $e->getMessage();
}

Ejemplos prepare

$sql="insert into actor (first_name,last_name) values (:first_name,:last_name)";
    $parametros=[
      'first_name'=>'Perico',
      'last_name'=>'De los palotes'
    ];
    $st=$conn->prepare($sql);
    $st->execute($parametros);

 $sql="SELECT city FROM country join city using(country_id) where country=:country";
   $parametros=[
       'country'=>'Argentina'
   ];
   $st=$conn->prepare($sql);
   $st->execute($parametros);
   $ciudades=$st->fetchAll();
   print_r($ciudades);

  $sql="SELECT country FROM country  where country like :country";
   $parametros=[
       'country'=>'%ar%'
   ];
   $st=$conn->prepare($sql);
   $st->execute($parametros);
   $paises=$st->fetchAll();
   print_r($paises);

 $sql = "SELECT * FROM customer join address using(address_id)
            where email=:email and phone=:phone";
   
  $parametros=[
        'email'=>'mary.smith@sakilacustomer.org',
        'phone'=>'28303384290'
    ];
    $st=$conn->prepare($sql);
    $st->execute($parametros);
    $cliente=$st->fetch();
    if (empty($cliente)){
        echo "No sé quién eres";
    } else{
        echo "hola ".$cliente['first_name'];
    }


    $sql="update film set replacement_cost=replacement_cost*:descuento where rating=:rating";
    $parametros=[
        'descuento'=>0.9,
        'rating'=>'R'
    ];
    $st=$conn->prepare($sql);
    $st->execute($parametros);

CRUD actores sakila

actores.php

<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
    </head>
    <body>
        <?php
        $server = "localhost";
        $user = "root";
        $password = "";
        $db = "sakila";
        ?>
        <form method="post">
            <p>Nombre<input type="text" name="first_name"></p>
            <p>Apellidos<input type="text" name="last_name"></p>
            <input type="submit">
        </form>
        <table>
            <tr><td>Id</td><td>Nombre</td><td>Apellido</td><td>Acciones</td>
            </tr>
            <?php
            try {
                $conn = new PDO("mysql:host=$server;dbname=$db;charset=UTF8", $user, $password);
                $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

                //Insertar el actor SI me lo mandas
                //Recuperar los datos de POST
                $first_name = filter_input(INPUT_POST, "first_name", FILTER_SANITIZE_MAGIC_QUOTES);
                $last_name = filter_input(INPUT_POST, "last_name", FILTER_SANITIZE_MAGIC_QUOTES);
                $actor_id = filter_input(INPUT_POST, "actor_id", FILTER_SANITIZE_NUMBER_INT);

                //Comprobar que me han mandado datos
                if (!empty($first_name) && !empty($last_name)) {
                       //Si me han mandado crear el SQL para insertar o actualizar
                 if (empty($actor_id)) {
                        $sql = "insert into actor(first_name,last_name) values ('$first_name','$last_name')";
                    } else {
                $sql = "update actor set first_name='$first_name', last_name='$last_name'"
                        . " where actor_id=$actor_id";
                    }
                    //Ejecutarlo
                    if ($conn->exec($sql) > 0) {
                        echo "Insertado el actor $first_name $last_name";
                    }
                }

                $borrar = filter_input(INPUT_GET, "borrar", FILTER_SANITIZE_NUMBER_INT);
                if (!empty($borrar)) {
                    $sql = "delete from actor where actor_id=$borrar";
                    if ($conn->exec($sql) > 0) {
                        echo "Borrado el actor $borrar";
                    }
                }


                //Muestra los actores
                $sql = "select * from actor";
                $q = $conn->query($sql);
                while ($row = $q->fetch()) {
                    ?> 
                    <tr><td><?= $row['actor_id'] ?></td>
                        <td><?= $row['first_name'] ?></td>
                        <td><?= $row['last_name'] ?></td>
                        <td><a href="actor_editar.php?actor_id=<?= $row['actor_id'] ?>">Editar</a>
                            <a href="?borrar=<?= $row['actor_id'] ?>">Borrar</a></td>
                    </tr>
                    <?php
                }
            } catch (Exception $e) {
                echo "Connection failed: " . $e->getMessage();
            }
            ?>
        </table>
    </body>
</html>

actor_editar.php

<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
    </head>
    <body>
        <?php
        $server = "localhost";
        $user = "root";
        $password = "";
        $db = "sakila";
        try {
            $conn = new PDO("mysql:host=$server;dbname=$db;charset=UTF8", $user, $password);
            $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            
            $actor_id= filter_input(INPUT_GET, "actor_id",FILTER_SANITIZE_NUMBER_INT);
            $sql="select * from actor where actor_id=$actor_id";
            $q=$conn->query($sql);
            $actor=$q->fetch();
            //print_r($actor);
            ?>
        <h2>Editar actor</h2>

        <form action="actores.php" method="post">
            <p>Id: <input readonly type="text" name="actor_id" value="<?=$actor['actor_id']?>"></p>
            <p>Nombre: <input type="text" name="first_name" value="<?=$actor['first_name']?>"></p>
            <p>Apellido: <input type="text" name="last_name" value="<?=$actor['last_name']?>"></p>
            <input type="submit">
        </form>
        <?php
            
            
        } catch (Exception $e) {
            echo "Connection failed: " . $e->getMessage();
        }
        ?>
    </body>
</html>

Examen BD 2019

Enlace al examen ¡Suerte!

Ejemplo de procedimientos almacenados

Parámetros entrada y salida:

CREATE PROCEDURE `test`(in id int, out p_actor varchar(100))
BEGIN
 select concat_ws(' ',first_name,last_name) into p_actor from actor where actor_id=id;
 
END

call test(2, @actor);

CREATE DEFINER=`root`@`localhost` PROCEDURE `suma`(in a int, in b int, out suma int)
BEGIN
set suma=a+b;
END

call suma(8,9,@res);

Alta de registros con comprobación incluída:

CREATE DEFINER=`root`@`localhost` PROCEDURE `alta_actor`(in nombre varchar(100), in apellido varchar(100))
BEGIN
declare c int;
select count(*) into c from actor where first_name=nombre and last_name=apellido;
if c=0 and length(nombre)>1 and length(apellido)>1 then
 insert into actor (first_name, last_name) values (nombre, apellido);
end if;
END

call alta_actor ('juan','pa');
call alta_actor ('juan','pa');  --No funcionará por repetido
call alta_actor ('juan','p');   -- no funcionará por longitud

Ejemplo de cursor:

CREATE PROCEDURE `cursor_ejemplo`(out total int)
BEGIN

DECLARE final int DEFAULT 0;

declare nombre varchar(100);

DECLARE mi_cursor CURSOR FOR SELECT first_name FROM actor;

DECLARE CONTINUE HANDLER FOR NOT FOUND SET final = 1;
set total=0;
OPEN mi_cursor;

while final=0 do

fetch mi_cursor into nombre;

if nombre like '%z%' then
 set total=total+1;
end if;

end while;

CLOSE mi_cursor;

END


call cursor_ejemplo(@t);

Procedimientos almacenados

Ejemplos de procedimientos almacenados

CREATE DEFINER=`root`@`localhost`
 PROCEDURE film_in_stock
 (IN p_film_id INT, IN p_store_id INT,
 OUT p_film_count INT)
 READS SQL DATA
BEGIN
 SELECT inventory_id
 FROM inventory
 WHERE film_id = p_film_id
 AND store_id = p_store_id
 AND inventory_in_stock(inventory_id);

 SELECT FOUND_ROWS() INTO p_film_count;
END

call film_in_stock(123,1,@w);
select @w

CREATE DEFINER=`root`@`localhost` PROCEDURE 
`actores_por_categoria`
(in p_categoria varchar(50))
BEGIN
select distinct concat(first_name,' ',last_name) actor 
from actor join film_actor using (actor_id)
join film using (film_id)
join film_category using (film_id)
join category c using (category_id)
where c.name=p_categoria
order by actor;

END

call actores_por_categoria('Animation')

Creando vistas en mysql

Categorías, películas y actores:

create view pelistotal as
select category_id, category.name nombrecategoria,
film_id,title,actor_id,
first_name,last_name 
from category join film_category using (category_id)
join film using (film_id)
join film_actor using (film_id)
join actor using (actor_id)

La usamos como una tabla normal:

select name,count(actor_id) total 
from pelistotal 
group by category_id

select * from actor 
where actor_id not in (
SELECT actor_id FROM pelistotal where name='action');

Como hacer una consulta del tipo actores que no han trabajado en películas de acción si usar subconsultas. Primero creamos la vista en positivo:

create view actores_accion as 
select actor_id,first_name,last_name from 
category join film_category using (category_id)
join film using (film_id)
join film_actor using (film_id)
join actor using (actor_id) 
where name='action'

Y después hacemos un left join y buscamos los nulos:

SELECT * FROM actor left join actores_accion using(actor_id)
where actores_accion.first_name is null

Ejemplos Create view

create view peliculas_pais as
select country, count(rental_id) total
from country join city using (country_id)
join address using(city_id)
join customer using(address_id)
join rental using(customer_id)
group by country_id

CREATE VIEW peliculas_categoria AS
select name, count(film_id) total
from category join film_category using (category_id)
group by category_id

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Examen PHP Acceso a datos

Insertar cliente