Mes: abril 2018

Php foreach

 <?php
 $a = [2, 5, 2, 3, 5];
 foreach ($a as $v) {
 echo $v . "<br/>";
 }
 $a[7]=9;
 $a['juan']='pablo';
 foreach ($a as $clave=>$valor) {
 echo $clave." - ".$valor . "<br/>";
 }
 for($i=0;$i<count($a);$i++){
 echo $a[$i] . "<br/>";
 }
 ?>

Php for

<?php
 for ($i = 0; $i < 10; $i += 2) {
 echo $i . "<br/>";
 }
 $i = 0;
 for (; $i < 10; $i += 2) {
 echo $i . "<br/>";
 }

$i = 0;
 for (; $i < 10;) {
 echo $i . "<br/>";
 $i += 2;
 }
 $i = 0;
 for (;;) {
 echo $i . "<br/>";
 $i += 2;
 if ($i > 10) {
 break;
 }
 }
 echo $i;
 ?>

Bucle while

<?php
 $a = 0;
 while ($a < 10) {
 echo "$a<br/>";
 $a += 2;
 }

$a = 0;
 while ($a < 10) {
 if ($a % 2 == 0) {
 echo "**<br/>";
 } else {
 echo "*****<br/>";
 }
 $a++;
 }

$a = 0;
 while ($a < 10) {
 if ($a % 2 == 0) {
 ?>
 <p style="background-color: black">.......</p>
 <?php
 } else {
 ?>
 <p style="background-color: red">.......</p>
 <?php
 }
 $a++;
 }
 ?>

Else if y switch

<?php
 $a = 1;

if ($a < 5) {
 echo '<div style="background-color: red">
 <h2>Menor de 5</h2>
 <h2>No estás autorizado a entrar</h2>
 </div>';
 } elseif ($a < 10) {
 echo "Menor de 10";
 } elseif ($a < 20) {
 echo "Menor de 20";
 } else {
 echo "Mayor de 20";
 }

switch ($a) {
 case 1:
 echo "Vale uno";
 break;
 case 2:
 case 3:
 echo "Vale 2 o 3";
 break;
 default:
 echo "Vale más de tres";
 }
 ?>

PHP if

<?php
 $a = 1;

if ($a < 5) {
 echo '<div style="background-color: red">
 <h2>Menor de 5</h2>
 <h2>No estás autorizado a entrar</h2>
 </div>';
 } else {
 echo "Mayor de 5";
 }
 if ($a < 5) {
 ?>
 <div style="background-color: red">
 <h2>Menor de 5</h2>
 <h2>No estás autorizado a entrar</h2>
 </div>
 <?php
 } else {
 ?>
 <h2>Menor de 5</h2>
 <?php
 }
 if ($a < 5):
 ?>
 <div style="background-color: red">
 <h2>Menor de 5</h2>
 <h2>No estás autorizado a entrar</h2>
 </div>
 <?php
 else:
 ?>
 <h2>Menor de 5</h2>
 <?php
 endif
 ?>

Ejemplos create view

Primero creamos una vista base:

create view country_payment as

select country, payment.* from country
join city using (country_id)
join address using (city_id)
join customer using (address_id)
join payment using (customer_id)

Después nos basamos en esta para crear las siguientes:

create view country_total as

select country, sum(amount) total from country_payment
group by country


create view country_month as

select country, month(payment_date) month, count(payment_id) total from country_payment
group by country, month